Editor’s Picks
Top papers matching your research interests in multimodal LLMs, audio and vision understanding/generation.
[1] Cross-Modal Bottleneck Fusion For Noise Robust Audio-Visual Speech Recognition
Seaone Ok, Min Jun Choi, Eungbeom Kim, Seungu Han, Kyogu Lee
Main category: eess.AS
TL;DR: CoBRA introduces a bottleneck-based fusion framework using learnable tokens to mediate cross-modal exchange between audio and visual streams for robust audio-visual speech recognition under noisy conditions.
Details
Motivation: Current AVSR systems need better fusion mechanisms that can effectively exploit visual information when audio is degraded by noise, while maintaining performance on clean speech. The challenge is designing a fusion approach that works reliably under adverse or out-of-domain noise conditions.Method: Proposes CoBRA (Cross-modal Bottleneck for Robust AVSR), a bottleneck-based fusion framework that introduces a compact set of learnable tokens to mediate cross-modal exchange. These tokens regulate information flow, allowing the audio stream to access essential visual cues even under noisy conditions.
Result: Despite limited training data, CoBRA surpasses comparable baselines and remains competitive with large-scale systems through noise-adaptive fusion. Ablation studies show that the depth of fusion is the most critical factor for robust AVSR performance.
Conclusion: CoBRA demonstrates both efficiency and robustness in AVSR through its bottleneck-based fusion approach, highlighting the importance of fusion depth in designing robust multimodal speech recognition systems.
Abstract: Audio-Visual Speech Recognition (AVSR) leverages both acoustic and visual cues to improve speech recognition under noisy conditions. A central question is how to design a fusion mechanism that allows the model to effectively exploit visual information when the audio signal is degraded, while maintaining strong performance on clean speech. We propose CoBRA (Cross-modal Bottleneck for Robust AVSR), a bottleneck-based fusion framework that introduces a compact set of learnable tokens to mediate cross-modal exchange. By regulating information flow through these tokens, the audio stream can reliably access essential visual cues even under adverse or out-of-domain noise. Despite limited training data, our model surpasses comparable baselines and remains competitive with large-scale systems through noise-adaptive fusion, demonstrating both efficiency and robustness. Ablation studies highlight that the depth of fusion is the most critical factor, underscoring its importance in designing robust AVSR systems.
Relevance: 9/10
[2] MENASpeechBank: A Reference Voice Bank with Persona-Conditioned Multi-Turn Conversations for AudioLLMs
Zien Sheikh Ali, Hunzalah Hassan Bhatti, Rabindra Nath Nandi, Shammur Absar Chowdhury, Firoj Alam
Main category: cs.SD
TL;DR: MENASpeechBank: A speech dataset with 18K utterances from 124 speakers across MENA countries, plus a pipeline to generate 417K synthetic persona-grounded conversations for AudioLLM training.
Details
Motivation: AudioLLMs need diverse, conversational, instruction-aligned speech-text data, especially for persona-grounded interactions and dialectal coverage. Real multi-speaker recordings are costly and slow to collect, creating a bottleneck for progress.Method: 1) Create MENASpeechBank with 18K high-quality utterances from 124 speakers across MENA countries; 2) Develop controllable synthetic data pipeline: construct persona profiles with World Values Survey attributes, define 5K conversational scenarios, match personas to scenarios via semantic similarity, generate 417K role-play conversations with LLM, synthesize user turns by conditioning on reference speaker audio.
Result: Created MENASpeechBank dataset and generated 417K synthetic conversations. Evaluated both synthetic and human-recorded conversations with detailed analysis. Will release both resources publicly.
Conclusion: The paper addresses the data bottleneck for AudioLLMs by providing a high-quality speech dataset and scalable synthetic data generation pipeline, enabling better persona-grounded and dialectally diverse audio language models.
Abstract: Audio large language models (AudioLLMs) enable instruction-following over speech and general audio, but progress is increasingly limited by the lack of diverse, conversational, instruction-aligned speech-text data. This bottleneck is especially acute for persona-grounded interactions and dialectal coverage, where collecting and releasing real multi-speaker recordings is costly and slow. We introduce MENASpeechBank, a reference speech bank comprising about 18K high-quality utterances from 124 speakers spanning multiple MENA countries, covering English, Modern Standard Arabic (MSA), and regional Arabic varieties. Building on this resource, we develop a controllable synthetic data pipeline that: (i) constructs persona profiles enriched with World Values Survey-inspired attributes, (ii) defines a taxonomy of about 5K conversational scenarios, (iii) matches personas to scenarios via semantic similarity, (iv) generates about 417K role-play conversations with an LLM where the user speaks as the persona and the assistant behaves as a helpful agent, and (v) synthesizes the user turns by conditioning on reference speaker audio to preserve speaker identity and diversity. We evaluate both synthetic and human-recorded conversations and provide detailed analysis. We will release MENASpeechBank and the generated conversations publicly for the community.
Relevance: 9/10
[3] Modality Gap-Driven Subspace Alignment Training Paradigm For Multimodal Large Language Models
Xiaomin Yu, Yi Xin, Wenjie Zhang, Chonghan Liu, Hanzhen Zhao, Xiaoxing Hu, Xinlei Yu, Ziyue Qiao, Hao Tang, Xue Yang, Xiaobin Hu, Chengwei Qin, Hui Xiong, Yu Qiao, Shuicheng Yan
Main category: cs.CV
TL;DR: ReAlign and ReVision framework addresses modality gap in multimodal learning using statistical alignment of unpaired data to enable efficient scaling of MLLMs
Details
Motivation: The modality gap - systematic offset between embeddings of different modalities expressing identical semantics - persists despite multimodal contrastive learning success. Prior approaches are limited by oversimplified isotropic assumptions, hindering large-scale application.Method: 1) Fixed-frame Modality Gap Theory decomposes gap into stable biases and anisotropic residuals. 2) ReAlign: training-free alignment strategy using massive unpaired data statistics with Anchor, Trace, and Centroid Alignment steps. 3) ReVision: scalable MLLM training paradigm integrating ReAlign into pretraining to learn visual representation distribution from unpaired text before visual instruction tuning.
Result: Framework demonstrates statistically aligned unpaired data can effectively substitute for expensive image-text pairs, offering robust path for efficient scaling of Multimodal Large Language Models.
Conclusion: Precise geometric characterization of modality gap enables efficient model scaling through statistical alignment of unpaired data, reducing reliance on large-scale, high-quality image-text pairs for MLLM development.
Abstract: Despite the success of multimodal contrastive learning in aligning visual and linguistic representations, a persistent geometric anomaly, the Modality Gap, remains: embeddings of distinct modalities expressing identical semantics occupy systematically offset regions. Prior approaches to bridge this gap are largely limited by oversimplified isotropic assumptions, hindering their application in large-scale scenarios. In this paper, we address these limitations by precisely characterizing the geometric shape of the modality gap and leveraging it for efficient model scaling. First, we propose the Fixed-frame Modality Gap Theory, which decomposes the modality gap within a frozen reference frame into stable biases and anisotropic residuals. Guided by this precise modeling, we introduce ReAlign, a training-free modality alignment strategy. Utilizing statistics from massive unpaired data, ReAlign aligns text representation into the image representation distribution via a three-step process comprising Anchor, Trace, and Centroid Alignment, thereby explicitly rectifying geometric misalignment. Building on ReAlign, we propose ReVision, a scalable training paradigm for Multimodal Large Language Models (MLLMs). ReVision integrates ReAlign into the pretraining stage, enabling the model to learn the distribution of visual representations from unpaired text before visual instruction tuning, without the need for large-scale, high-quality image-text pairs. Our framework demonstrates that statistically aligned unpaired data can effectively substitute for expensive image-text pairs, offering a robust path for the efficient scaling of MLLMs.
Relevance: 9/10
Today’s Research Highlights
AI-enhanced summaries of the latest research papers from arXiv.
Table of Contents
- cs.CL [Total: 185]
- cs.CV [Total: 314]
- cs.AI [Total: 180]
- cs.SD [Total: 14]
- cs.LG [Total: 450]
- cs.MA [Total: 15]
- cs.MM [Total: 4]
- eess.AS [Total: 11]
- eess.IV [Total: 24]
cs.CL
[1] Does Visual Rendering Bypass Tokenization? Investigating Script-Tokenizer Misalignment in Pixel-Based Language Models
Lucky Susanto, Musa Izzanardi Wijanarko, Khumaisa Nur’aini, Farid Adilazuarda, Alham Fikri Aji, Derry Tanti Wijaya
Main category: cs.CL
TL;DR: Pixel-based language modeling with visual text rendering still suffers from tokenizer misalignment when text tokenizers are reintroduced, as shown in Indonesian low-resource languages.
Details
Motivation: To investigate whether visual rendering truly decouples models from tokenization constraints, especially for low-resource languages with non-Latin scripts, and examine the impact of script-tokenizer alignment in multimodal architectures like DualGPT.Method: Evaluated four Indonesian low-resource languages (Javanese, Balinese, Sundanese, Lampungnese) with non-Latin scripts using DualGPT architecture. Compared Llama 2 tokenizer vs custom tokenizer despite visual rendering of text as images.
Result: Reintegrating text tokenizers reintroduces tokenizer misalignment problems. Llama 2 tokenizer performed significantly worse than custom tokenizer despite lower OOV and fertility rates, with improvements up to 30.15 chrF++ for custom tokenizer.
Conclusion: Visual rendering doesn’t fully decouple from tokenization constraints when text tokenizers are reintroduced. Text tokenizers remain a significant barrier to equitable multimodal models, especially for low-resource languages.
Abstract: While pixel-based language modeling aims to bypass the sub-word tokenization bottleneck by rendering text as images, recent multimodal variants such as DualGPT reintroduce text tokenizers to improve autoregressive performance. We investigate a fundamental question, does visual rendering truly decouple a model from tokenization constraints? Focusing on four Indonesian low-resource local languages that have their own non-Latin scripts (i.e., Javanese, Balinese, Sundanese, and Lampungnese), we evaluate the impact of script-tokenizer alignment within the DualGPT architecture. Our results show that, despite visual rendering, reintegrating a text tokenizer into the architecture reintroduces the same issue that pixel-based language modeling aims to resolve, which is the tokenizer misalignment problem. Despite having lower OOV and fertility rates, we show that the Llama 2 tokenizer performs significantly worse than a custom tokenizer, with improvements of up to 30.15 chrF++. Our findings serve as a warning for future multimodal variants, as text tokenizers remain a significant barrier to equitable models.
[2] BiomechAgent: AI-Assisted Biomechanical Analysis Through Code-Generating Agents
R. James Cotton, Thomas Leonard
Main category: cs.CL
TL;DR: BiomechAgent is an AI agent that enables biomechanical analysis through natural language, allowing clinicians to query databases, generate visualizations, and interpret motion capture data without programming expertise.
Details
Motivation: While markerless motion capture makes movement analysis more accessible, analyzing the resulting data remains challenging for clinicians without programming skills. There's a need for tools that bridge this gap and make biomechanical data more useful and accessible to end users.Method: Developed a code-generating AI agent (BiomechAgent) that uses natural language processing to enable biomechanical analysis. Created a systematic benchmark for evaluation spanning data retrieval, visualization, activity classification, temporal segmentation, and clinical reasoning. Tested design decisions including biomechanically-informed domain-specific instructions vs generic prompts, integration of specialized tools for gait event detection, and comparison of local open-weight models vs frontier cloud-based LLMs.
Result: BiomechAgent achieved robust accuracy on data retrieval and visualization tasks and demonstrated emerging clinical reasoning capabilities. Domain-specific instructions significantly improved performance over generic prompts. Integration of specialized gait event detection tools substantially boosted accuracy on challenging spatiotemporal analysis. Local open-weight models performed substantially worse than frontier cloud-based LLMs in most domains except database retrieval.
Conclusion: BiomechAgent successfully makes motion capture data more useful and accessible to clinicians without programming expertise by enabling natural language-based biomechanical analysis. The system demonstrates the importance of domain-specific knowledge and specialized tool integration for effective AI agents in clinical biomechanics.
Abstract: Markerless motion capture is making quantitative movement analysis increasingly accessible, yet analyzing the resulting data remains a barrier for clinicians without programming expertise. We present BiomechAgent, a code-generating AI agent that enables biomechanical analysis through natural language and allows users to querying databases, generating visualizations, and even interpret data without requiring users to write code. To evaluate BiomechAgent’s capabilities, we developed a systematic benchmark spanning data retrieval, visualization, activity classification, temporal segmentation, and clinical reasoning. BiomechAgent achieved robust accuracy on data retrieval and visualization tasks and demonstrated emerging clinical reasoning capabilities. We used our dataset to systematically evaluate several of our design decisions. Biomechanically-informed, domain-specific instructions significantly improved performance over generic prompts, and integrating validated specialized tools for gait event detection substantially boosted accuracy on challenging spatiotemporal analysis where the base agent struggled. We also tested BiomechAgent using a local open-weight model instead of a frontier cloud based LLM and found that perform was substantially diminished in most domains other than database retrieval. In short, BiomechAgent makes the data from accessible motion capture and much more useful and accessible to end users.
[3] Bridging the Knowledge Void: Inference-time Acquisition of Unfamiliar Programming Languages for Coding Tasks
Chen Shen, Wei Cheng, Jingyue Yang, Huan Zhang, Yuhan Wu, Wei Hu
Main category: cs.CL
TL;DR: ILA-agent enables LLMs to learn unfamiliar programming languages at inference time through structured interactions with documentation and execution environments, evaluated on novel language Cangjie.
Details
Motivation: LLMs struggle with unfamiliar programming languages despite extensive pre-training, and data-intensive fine-tuning is impractical for low-resource languages. The paper investigates inference-time language acquisition as an alternative paradigm.Method: Proposes ILA-agent framework with behavioral primitives modeled as tools, allowing LLMs to incrementally explore, apply, and verify language knowledge through structured interactions with official documentation and execution environments.
Result: ILA-agent significantly outperforms retrieval-augmented baselines across code generation, translation, and program repair tasks on the Cangjie benchmark. Analysis reveals emergent behavior patterns but persisting performance gaps.
Conclusion: Inference-time language acquisition is a viable paradigm for LLMs to master unfamiliar programming languages without extensive fine-tuning, though challenges remain in bridging performance gaps.
Abstract: The proficiency of Large Language Models (LLMs) in coding tasks is often a reflection of their extensive pre-training corpora, which typically collapses when confronted with previously unfamiliar programming languages. Departing from data-intensive finetuning, we investigate the paradigm of Inference-time Language Acquisition (ILA), where an LLM masters an unfamiliar language through dynamic interaction with limited external resources. In this paper, we propose ILA-agent, a general ILA framework that equips LLMs with a set of behavioral primitives. By modeling essential human-like behaviors as a suite of tools, ILA-agent enables LLMs to incrementally explore, apply, and verify language knowledge through structured interactions with the official documentation and execution environment. To provide a rigorous evaluation in a low-resource setting, we construct Cangjie-bench, a multi-task benchmark based on the novel statically-typed language Cangjie. We instantiate ILA-agent for Cangjie and evaluate its performance across code generation, translation, and program repair tasks. Results using diverse LLMs demonstrate that ILA-agent significantly outperforms retrieval-augmented baselines. Further analysis of agent trajectories characterizes the emergent behavior patterns while highlighting persisting performance gaps.
[4] Anchored Decoding: Provably Reducing Copyright Risk for Any Language Model
Jacqueline He, Jonathan Hayase, Wen-tau Yih, Sewoong Oh, Luke Zettlemoyer, Pang Wei Koh
Main category: cs.CL
TL;DR: Anchored Decoding is an inference-time method that suppresses verbatim copying from language models by constraining generation to stay near a permissively trained safe LM, with a byte-level variant for cross-vocabulary fusion.
Details
Motivation: Address privacy, copyright, and compliance risks when LMs memorize and emit verbatim training data, especially from sensitive or copyright-protected sources, without requiring retraining of existing models.Method: Proposes Anchored Decoding that adaptively allocates information budget over generation trajectory, enforcing per-step constraints for sequence-level guarantees. Also introduces AnchoredByte Decoding for byte-level cross-vocabulary fusion via ByteSampler framework, plus TinyComma 1.8B as a permissively trained safe model.
Result: Eliminates up to 75% of measurable copying gap between risky baseline and safe reference while preserving near-original fluency and factuality, with modest inference overhead. Defines new Pareto frontier for risk-utility trade-off across six model pairs.
Conclusion: Anchored Decoding provides effective plug-and-play solution for reducing verbatim copying in LMs without retraining, enabling practical compliance with copyright and privacy concerns through tunable risk-utility trade-offs.
Abstract: Modern language models (LMs) tend to memorize portions of their training data and emit verbatim spans. When the underlying sources are sensitive or copyright-protected, such reproduction raises issues of consent and compensation for creators and compliance risks for developers. We propose Anchored Decoding, a plug-and-play inference-time method for suppressing verbatim copying: it enables decoding from any risky LM trained on mixed-license data by keeping generation in bounded proximity to a permissively trained safe LM. Anchored Decoding adaptively allocates a user-chosen information budget over the generation trajectory and enforces per-step constraints that yield a sequence-level guarantee, enabling a tunable risk-utility trade-off. To make Anchored Decoding practically useful, we introduce a new permissively trained safe model (TinyComma 1.8B), as well as Anchored${\mathrm{Byte}}$ Decoding, a byte-level variant of our method that enables cross-vocabulary fusion via the ByteSampler framework (Hayase et al., 2025). We evaluate our methods across six model pairs on long-form evaluations of copyright risk and utility. Anchored and Anchored${\mathrm{Byte}}$ Decoding define a new Pareto frontier, preserving near-original fluency and factuality while eliminating up to 75% of the measurable copying gap (averaged over six copying metrics) between the risky baseline and a safe reference, at a modest inference overhead.
[5] Free Energy Mixer
Jiecheng Lu, Shihao Yang
Main category: cs.CL
TL;DR: FEM is a novel attention mechanism that replaces standard convex averaging with value-driven per-channel selection using free-energy (log-sum-exp) reads, enabling smooth transition from averaging to selection while maintaining computational complexity.
Details
Motivation: Standard attention mechanisms use convex averaging which blocks channel-wise selection, limiting their ability to perform selective information extraction. The authors aim to create a more flexible attention mechanism that can smoothly transition between averaging and per-channel selection.Method: Proposes Free Energy Mixer (FEM) that uses free-energy (log-sum-exp) reads with value-driven per-channel log-linear tilts applied to a fast prior (from queries/keys). It treats standard attention scoring as a prior and computes value-aware posterior reads. A two-level gated FEM is implemented that’s plug-and-play with standard/linear attention, linear RNNs, and SSMs.
Result: FEM consistently outperforms strong baselines on NLP, vision, and time-series tasks at matched parameter budgets, demonstrating improved performance across multiple domains.
Conclusion: FEM provides a principled way to enhance attention mechanisms with value-driven selection capabilities while maintaining computational efficiency, offering a promising direction for improving multimodal understanding architectures.
Abstract: Standard attention stores keys/values losslessly but reads them via a per-head convex average, blocking channel-wise selection. We propose the Free Energy Mixer (FEM): a free-energy (log-sum-exp) read that applies a value-driven, per-channel log-linear tilt to a fast prior (e.g., from queries/keys in standard attention) over indices. Unlike methods that attempt to improve and enrich the $(q,k)$ scoring distribution, FEM treats it as a prior and yields a value-aware posterior read at unchanged complexity, smoothly moving from averaging to per-channel selection as the learnable inverse temperature increases, while still preserving parallelism and the original asymptotic complexity ($O(T^2)$ for softmax; $O(T)$ for linearizable variants). We instantiate a two-level gated FEM that is plug-and-play with standard and linear attention, linear RNNs and SSMs. It consistently outperforms strong baselines on NLP, vision, and time-series at matched parameter budgets.
[6] Your Language Model Secretly Contains Personality Subnetworks
Ruimeng Ye, Zihan Wang, Zinan Ling, Yang Xiao, Manling Li, Xiaolong Ma, Bo Hui
Main category: cs.CL
TL;DR: LLMs contain persona-specialized subnetworks in their parameters that can be isolated without external knowledge or training, enabling efficient persona adaptation through activation-guided masking and contrastive pruning.
Details
Motivation: Current approaches for persona adaptation in LLMs rely on external knowledge like prompting, RAG, or fine-tuning. The authors question whether LLMs already have persona knowledge embedded in their parameters and aim to discover if persona-specialized subnetworks exist internally.Method: Using small calibration datasets, identify activation signatures for different personas. Develop masking strategy to isolate lightweight persona subnetworks. For binary-opposing personas, introduce contrastive pruning to identify parameters responsible for statistical divergence between opposing personas. Entirely training-free approach.
Result: The resulting subnetworks exhibit significantly stronger persona alignment than baselines requiring external knowledge while being more efficient. Diverse human-like behaviors are already embedded in LLM parameter space.
Conclusion: LLMs contain embedded persona-specialized subnetworks that can be isolated without external knowledge, pointing toward new perspectives on controllable and interpretable personalization in large language models.
Abstract: Humans shift between different personas depending on social context. Large Language Models (LLMs) demonstrate a similar flexibility in adopting different personas and behaviors. Existing approaches, however, typically adapt such behavior through external knowledge such as prompting, retrieval-augmented generation (RAG), or fine-tuning. We ask: do LLMs really need external context or parameters to adapt to different behaviors, or do they already have such knowledge embedded in their parameters? In this work, we show that LLMs already contain persona-specialized subnetworks in their parameter space. Using small calibration datasets, we identify distinct activation signatures associated with different personas. Guided by these statistics, we develop a masking strategy that isolates lightweight persona subnetworks. Building on the findings, we further discuss: how can we discover opposing subnetwork from the model that lead to binary-opposing personas, such as introvert-extrovert? To further enhance separation in binary opposition scenarios, we introduce a contrastive pruning strategy that identifies parameters responsible for the statistical divergence between opposing personas. Our method is entirely training-free and relies solely on the language model’s existing parameter space. Across diverse evaluation settings, the resulting subnetworks exhibit significantly stronger persona alignment than baselines that require external knowledge while being more efficient. Our findings suggest that diverse human-like behaviors are not merely induced in LLMs, but are already embedded in their parameter space, pointing toward a new perspective on controllable and interpretable personalization in large language models.
[7] Open TutorAI: An Open-source Platform for Personalized and Immersive Learning with Generative AI
Mohamed El Hajji, Tarek Ait Baha, Aicha Dakir, Hammou Fadili, Youssef Es-Saady
Main category: cs.CL
TL;DR: Open TutorAI is an open-source educational platform using LLMs and generative AI with 3D avatars for personalized, multimodal tutoring that adapts to individual learner profiles.
Details
Motivation: Existing educational chatbots lack contextual adaptability, real-time responsiveness, and pedagogical agility, limiting learner engagement and instructional effectiveness. There's a need for open platforms combining AI and immersive technologies for personalized learning.Method: The system integrates natural language processing with customizable 3D avatars for multimodal interaction. It uses a structured onboarding process to capture learner goals/preferences, configures learner-specific AI assistants accessible via text and avatar interfaces, and includes tools for content organization, embedded feedback, and analytics.
Result: Open TutorAI delivers adaptive support responding to individual learner profiles without requiring technical expertise. The assistant-generation pipeline and avatar integration enhance engagement and emotional presence, creating a more humanized, immersive learning environment.
Conclusion: Open TutorAI unites modular architecture, generative AI, and learner analytics within an open-source framework, contributing to next-generation intelligent tutoring systems that combine AI and immersive technologies for personalized education.
Abstract: Recent advances in artificial intelligence have created new possibilities for making education more scalable, adaptive, and learner-centered. However, existing educational chatbot systems often lack contextual adaptability, real-time responsiveness, and pedagogical agility. which can limit learner engagement and diminish instructional effectiveness. Thus, there is a growing need for open, integrative platforms that combine AI and immersive technologies to support personalized, meaningful learning experiences. This paper presents Open TutorAI, an open-source educational platform based on LLMs and generative technologies that provides dynamic, personalized tutoring. The system integrates natural language processing with customizable 3D avatars to enable multimodal learner interaction. Through a structured onboarding process, it captures each learner’s goals and preferences in order to configure a learner-specific AI assistant. This assistant is accessible via both text-based and avatar-driven interfaces. The platform includes tools for organizing content, providing embedded feedback, and offering dedicated interfaces for learners, educators, and parents. This work focuses on learner-facing components, delivering a tool for adaptive support that responds to individual learner profiles without requiring technical expertise. Its assistant-generation pipeline and avatar integration enhance engagement and emotional presence, creating a more humanized, immersive learning environment. Embedded learning analytics support self-regulated learning by tracking engagement patterns and generating actionable feedback. The result is Open TutorAI, which unites modular architecture, generative AI, and learner analytics within an open-source framework. It contributes to the development of next-generation intelligent tutoring systems.
[8] Can LLMs Discern the Traits Influencing Your Preferences? Evaluating Personality-Driven Preference Alignment in LLMs
Tianyu Zhao, Siqi Li, Yasser Shoukry, Salma Elmalaki
Main category: cs.CL
TL;DR: Personality traits can serve as a latent signal to filter noisy user preferences for better LLM personalization, with personality-aligned preferences improving answer accuracy from 29.25% to 76%.
Details
Motivation: User preferences used for LLM personalization are often noisy, incomplete, or misleading, which can degrade answer quality when applied naively. The paper is motivated by the observation that stable personality traits shape everyday preferences, suggesting personality could serve as a principled latent signal behind preference statements.Method: 1) Study personality as a latent signal behind preference statements through experiments showing personality-aligned preferences improve personalized QA; 2) Create PACIFIC dataset containing 1200 preference statements annotated with Big-Five (OCEAN) trait directions across diverse domains; 3) Propose a framework enabling LLMs to automatically retrieve personality-aligned preferences and incorporate them during answer generation.
Result: Conditioning on personality-aligned preferences substantially improves personalized question answering: selecting preferences consistent with a user’s inferred personality increases answer-choice accuracy from 29.25% to 76%, compared to using randomly selected preferences.
Conclusion: Personality traits provide a reliable latent signal for filtering noisy user preferences, enabling more effective LLM personalization. The PACIFIC dataset and proposed framework offer practical tools for leveraging personality-aligned preferences in answer generation.
Abstract: User preferences are increasingly used to personalize Large Language Model (LLM) responses, yet how to reliably leverage preference signals for answer generation remains under-explored. In practice, preferences can be noisy, incomplete, or even misleading, which can degrade answer quality when applied naively. Motivated by the observation that stable personality traits shape everyday preferences, we study personality as a principled ‘’latent’’ signal behind preference statements. Through extensive experiments, we find that conditioning on personality-aligned preferences substantially improves personalized question answering: selecting preferences consistent with a user’s inferred personality increases answer-choice accuracy from 29.25% to 76%, compared to using randomly selected preferences. Based on these findings, we introduce PACIFIC (Preference Alignment Choices Inference for Five-factor Identity Characterization), a personality-labeled preference dataset containing 1200 preference statements spanning diverse domains (e.g., travel, movies, education), annotated with Big-Five (OCEAN) trait directions. Finally, we propose a framework that enables an LLM model to automatically retrieve personality-aligned preferences and incorporate them during answer generation.
[9] Long-Context Long-Form Question Answering for Legal Domain
Anagha Kulkarni, Parin Rajesh Jhaveri, Prasha Shrestha, Yu Tong Han, Reza Amini, Behrouz Madahian
Main category: cs.CL
TL;DR: A QA system for legal documents that handles complex layouts, domain vocabulary, and generates comprehensive long-form answers with a novel coverage metric.
Details
Motivation: Legal documents present unique challenges for QA: complex layouts with nested sections and footnotes, specialized vocabulary, and requirements for long-context understanding and comprehensive long-form answers.Method: Proposed system with three key components: (1) deconstructing domain-specific vocabulary for better retrieval, (2) parsing complex document layouts while isolating sections and footnotes with proper linking, (3) generating comprehensive answers using precise domain vocabulary. Also introduces a coverage metric for recall evaluation.
Result: System evaluated on a professionally curated QA dataset with comprehensive experiments and ablation studies demonstrating usability and merit.
Conclusion: The proposed system effectively addresses the challenges of long-context QA for legal documents with complex layouts and specialized vocabulary, providing comprehensive long-form answers.
Abstract: Legal documents have complex document layouts involving multiple nested sections, lengthy footnotes and further use specialized linguistic devices like intricate syntax and domain-specific vocabulary to ensure precision and authority. These inherent characteristics of legal documents make question answering challenging, and particularly so when the answer to the question spans several pages (i.e. requires long-context) and is required to be comprehensive (i.e. a long-form answer). In this paper, we address the challenges of long-context question answering in context of long-form answers given the idiosyncrasies of legal documents. We propose a question answering system that can (a) deconstruct domain-specific vocabulary for better retrieval from source documents, (b) parse complex document layouts while isolating sections and footnotes and linking them appropriately, (c) generate comprehensive answers using precise domain-specific vocabulary. We also introduce a coverage metric that classifies the performance into recall-based coverage categories allowing human users to evaluate the recall with ease. We curate a QA dataset by leveraging the expertise of professionals from fields such as law and corporate tax. Through comprehensive experiments and ablation studies, we demonstrate the usability and merit of the proposed system.
[10] Equipping LLM with Directional Multi-Talker Speech Understanding Capabilities
Ju Lin, Jing Pan, Ruizhi Li, Ming Sun, Yuzong Liu, Alaa Hassan, Jing Zheng, Florian Metze
Main category: cs.CL
TL;DR: LLMs can be enhanced with directional multi-talker speech understanding using smart glasses microphone arrays through cascaded source separation or end-to-end serialized output approaches.
Details
Motivation: Most speech LLMs are trained on single-channel, single-talker data, making them unsuitable for real-world multi-talker, multi-channel scenarios like smart glasses applications that require directional speech understanding.Method: Two approaches: (1) Cascaded system with source separation front-end module, (2) End-to-end system using serialized output training. Both utilize multi-microphone arrays in smart glasses for streaming directional processing.
Result: Experimental results show strong performance in speech recognition and translation tasks, demonstrating effective directional speech understanding capabilities for LLMs.
Conclusion: The proposed methods successfully enable LLMs to handle directional multi-talker speech understanding, particularly valuable for smart glasses applications with embedded microphone arrays.
Abstract: Recent studies have demonstrated that prompting large language models (LLM) with audio encodings enables effective speech understanding capabilities. However, most speech LLMs are trained on single-channel, single-talker data, which makes it challenging to directly apply them to multi-talker and multi-channel speech understanding task. In this work, we present a comprehensive investigation on how to enable directional multi-talker speech understanding capabilities for LLMs, specifically in smart glasses usecase. We propose two novel approaches to integrate directivity into LLMs: (1) a cascaded system that leverages a source separation front-end module, and (2) an end-to-end system that utilizes serialized output training. All of the approaches utilize a multi-microphone array embedded in smart glasses to optimize directivity interpretation and processing in a streaming manner. Experimental results demonstrate the efficacy of our proposed methods in endowing LLMs with directional speech understanding capabilities, achieving strong performance in both speech recognition and speech translation tasks.
[11] Beyond Accuracy: Risk-Sensitive Evaluation of Hallucinated Medical Advice
Savan Doshi
Main category: cs.CL
TL;DR: Proposes a risk-sensitive evaluation framework for medical LLM hallucinations that quantifies harm potential of unsupported but actionable medical language rather than just factual correctness.
Details
Motivation: Existing hallucination evaluation in medical QA focuses only on factual correctness, treating all errors equally, which obscures clinically relevant failure modes where models generate unsupported but actionable medical advice that could cause harm if followed.Method: Develops a framework that identifies risk-bearing language (treatment directives, contraindications, urgency cues, high-risk medications) and combines risk scoring with relevance measures to identify high-risk, low-grounding failures. Tests on three instruction-tuned LLMs using controlled safety stress test prompts.
Result: Models with similar surface-level behavior show substantially different risk profiles, and standard evaluation metrics fail to capture these distinctions, highlighting the importance of risk-sensitive evaluation.
Conclusion: Risk sensitivity must be incorporated into hallucination evaluation for medical applications, and evaluation validity depends critically on task and prompt design to properly assess safety risks.
Abstract: Large language models are increasingly being used in patient-facing medical question answering, where hallucinated outputs can vary widely in potential harm. However, existing hallucination standards and evaluation metrics focus primarily on factual correctness, treating all errors as equally severe. This obscures clinically relevant failure modes, particularly when models generate unsupported but actionable medical language. We propose a risk-sensitive evaluation framework that quantifies hallucinations through the presence of risk-bearing language, including treatment directives, contraindications, urgency cues, and mentions of high-risk medications. Rather than assessing clinical correctness, our approach evaluates the potential impact of hallucinated content if acted upon. We further combine risk scoring with a relevance measure to identify high-risk, low-grounding failures. We apply this framework to three instruction-tuned language models using controlled patient-facing prompts designed as safety stress tests. Our results show that models with similar surface-level behavior exhibit substantially different risk profiles and that standard evaluation metrics fail to capture these distinctions. These findings highlight the importance of incorporating risk sensitivity into hallucination evaluation and suggest that evaluation validity is critically dependent on task and prompt design.
[12] STITCH: Simultaneous Thinking and Talking with Chunked Reasoning for Spoken Language Models
Cheng-Han Chiang, Xiaofei Wang, Linjie Li, Chung-Ching Lin, Kevin Lin, Shujie Liu, Zhendong Wang, Zhengyuan Yang, Hung-yi Lee, Lijuan Wang
Main category: cs.CL
TL;DR: STITCH enables spoken language models to think internally while talking by alternating between unspoken reasoning chunks and spoken response chunks, eliminating latency overhead for chain-of-thought reasoning.
Details
Motivation: Current spoken language models lack internal thinking processes before responding, unlike humans who engage in complex mental reasoning. While chain-of-thought reasoning could help, generating complete CoT before speaking introduces unacceptable latency for real-time speech interactions.Method: Proposes STITCH, a generation method that alternates between generating unspoken reasoning chunks and spoken response chunks. Leverages the fact that audio playback time for spoken chunks is longer than token generation time, using the remaining time to generate unspoken reasoning tokens, enabling simultaneous thinking and talking.
Result: STITCH matches the latency of baselines that cannot generate unspoken CoT while outperforming them by 15% on math reasoning datasets. Performs equally well on non-reasoning datasets as baseline models.
Conclusion: STITCH successfully enables spoken language models to perform internal reasoning without adding latency, bridging the gap between human-like thinking processes and real-time speech generation.
Abstract: Spoken Language Models (SLMs) are designed to take speech inputs and produce spoken responses. However, current SLMs lack the ability to perform an internal, unspoken thinking process before responding. In contrast, humans typically engage in complex mental reasoning internally, enabling them to communicate ideas clearly and concisely. Thus, integrating an unspoken thought process into SLMs is highly desirable. While naively generating a complete chain-of-thought (CoT) reasoning before starting to talk can enable thinking for SLMs, this induces additional latency for the speech response, as the CoT reasoning can be arbitrarily long. To solve this issue, we propose Stitch, a novel generation method that alternates between the generation of unspoken reasoning chunks and spoken response chunks. Since the audio duration of a chunk of spoken response is much longer than the time to generate the tokens in a chunk of spoken response, we use the remaining free time to generate the unspoken reasoning tokens. When a chunk of audio is played to the user, the model continues to generate the next unspoken reasoning chunk, achieving simultaneous thinking and talking. Remarkably, Stitch matches the latency of baselines that cannot generate unspoken CoT by design while outperforming those baselines by 15% on math reasoning datasets; Stitch also performs equally well on non-reasoning datasets as those baseline models. Some animations and demonstrations are on the project page: https://d223302.github.io/STITCH.
[13] Intent Mismatch Causes LLMs to Get Lost in Multi-Turn Conversation
Geng Liu, Fei Zhu, Rong Feng, Changyi Ma, Shiqi Wang, Gaofeng Meng
Main category: cs.CL
TL;DR: The paper identifies that LLMs’ performance drop in multi-turn conversations (Lost in Conversation) stems from intent alignment gaps rather than capability deficits, and proposes a Mediator-Assistant architecture to bridge this gap.
Details
Motivation: LLMs suffer substantial performance degradation in multi-turn conversations compared to single-turn interactions, which prior work attributed to model unreliability. The authors argue this is actually an intent alignment gap between users and models.Method: Proposes a Mediator-Assistant architecture that decouples intent understanding from task execution. Uses an experience-driven Mediator to explicate vague user inputs into explicit, well-structured instructions based on historical interaction patterns.
Result: Experimental results show the method significantly mitigates performance degradation in multi-turn conversations across diverse LLMs.
Conclusion: Lost in Conversation is not a capability failure but an interaction breakdown; scaling model size alone cannot fix it; the Mediator-Assistant architecture effectively bridges intent alignment gaps.
Abstract: Multi-turn conversation has emerged as a predominant interaction paradigm for Large Language Models (LLMs). Users often employ follow-up questions to refine their intent, expecting LLMs to adapt dynamically. However, recent research reveals that LLMs suffer a substantial performance drop in multi-turn settings compared to single-turn interactions with fully specified instructions, a phenomenon termed ``Lost in Conversation’’ (LiC). While this prior work attributes LiC to model unreliability, we argue that the root cause lies in an intent alignment gap rather than intrinsic capability deficits. In this paper, we first demonstrate that LiC is not a failure of model capability but rather a breakdown in interaction between users and LLMs. We theoretically show that scaling model size or improving training alone cannot resolve this gap, as it arises from structural ambiguity in conversational context rather than representational limitations. To address this, we propose to decouple intent understanding from task execution through a Mediator-Assistant architecture. By utilizing an experience-driven Mediator to explicate user inputs into explicit, well-structured instructions based on historical interaction patterns, our approach effectively bridges the gap between vague user intent and model interpretation. Experimental results demonstrate that this method significantly mitigates performance degradation in multi-turn conversations across diverse LLMs.
[14] VocalNet-MDM: Accelerating Streaming Speech LLM via Self-Distilled Masked Diffusion Modeling
Ziyang Cheng, Yuhao Wang, Heyang Liu, Ronghua Wu, Qunshan Gu, Yanfeng Wang, Yu Wang
Main category: cs.CL
TL;DR: VocalNet-MDM introduces masked diffusion modeling as a non-autoregressive alternative to autoregressive speech LLMs, achieving significant speedups and latency reduction while maintaining quality.
Details
Motivation: Current speech LLMs use autoregressive paradigms that impose serial constraints, limiting generation efficiency and introducing exposure bias. The authors seek to explore non-autoregressive alternatives for better efficiency and lower latency in speech interaction.Method: Proposes VocalNet-MDM using Masked Diffusion Modeling with Hierarchical Block-wise Masking to align training with progressive masked states during block diffusion decoding, and Iterative Self-Distillation to compress multi-step refinement into fewer steps for low-latency inference.
Result: Achieves 3.7×-10× decoding speedup, reduces first-chunk latency by 34% compared to AR baselines, maintains competitive recognition accuracy, and achieves state-of-the-art text quality and speech naturalness with only 6K hours of training data.
Conclusion: Masked Diffusion Modeling is a promising and scalable alternative for low-latency, efficient speech LLMs, demonstrating that non-autoregressive approaches can achieve both efficiency and quality improvements.
Abstract: Recent Speech Large Language Models~(LLMs) have achieved impressive capabilities in end-to-end speech interaction. However, the prevailing autoregressive paradigm imposes strict serial constraints, limiting generation efficiency and introducing exposure bias. In this paper, we investigate Masked Diffusion Modeling~(MDM) as a non-autoregressive paradigm for speech LLMs and introduce VocalNet-MDM. To adapt MDM for streaming speech interaction, we address two critical challenges: training-inference mismatch and iterative overhead. We propose Hierarchical Block-wise Masking to align training objectives with the progressive masked states encountered during block diffusion decoding, and Iterative Self-Distillation to compress multi-step refinement into fewer steps for low-latency inference. Trained on a limited scale of only 6K hours of speech data, VocalNet-MDM achieves a 3.7$\times$–10$\times$ decoding speedup and reduces first-chunk latency by 34% compared to AR baselines. It maintains competitive recognition accuracy while achieving state-of-the-art text quality and speech naturalness, demonstrating that MDM is a promising and scalable alternative for low-latency, efficient speech LLMs.
[15] ViHERMES: A Graph-Grounded Multihop Question Answering Benchmark and System for Vietnamese Healthcare Regulations
Long S. T. Nguyen, Quan M. Bui, Tin T. Ngo, Quynh T. N. Vo, Dung N. H. Le, Tho T. Quan
Main category: cs.CL
TL;DR: ViHERMES: A Vietnamese healthcare regulatory QA benchmark requiring multihop reasoning across interdependent legal documents, with a graph-aware retrieval framework for improved performance.
Details
Motivation: Addressing the lack of benchmark datasets for multihop reasoning over regulatory documents, especially in low-resource languages like Vietnamese, where healthcare regulations are hierarchically structured and frequently revised through amendments and cross-references.Method: Proposes ViHERMES dataset construction using controlled multihop QA generation pipeline based on semantic clustering and graph-inspired data mining, followed by LLM-based generation with structured evidence. Also presents a graph-aware retrieval framework modeling formal legal relations at legal unit level.
Result: ViHERMES provides a challenging benchmark for evaluating multihop regulatory QA systems, and the proposed graph-aware approach consistently outperforms strong retrieval-based baselines.
Conclusion: The work introduces a valuable benchmark for multihop reasoning over healthcare regulations in Vietnamese, with a graph-aware framework that improves QA performance on regulatory documents.
Abstract: Question Answering (QA) over regulatory documents is inherently challenging due to the need for multihop reasoning across legally interdependent texts, a requirement that is particularly pronounced in the healthcare domain where regulations are hierarchically structured and frequently revised through amendments and cross-references. Despite recent progress in retrieval-augmented and graph-based QA methods, systematic evaluation in this setting remains limited, especially for low-resource languages such as Vietnamese, due to the lack of benchmark datasets that explicitly support multihop reasoning over healthcare regulations. In this work, we introduce the Vietnamese Healthcare Regulations-Multihop Reasoning Dataset (ViHERMES), a benchmark designed for multihop QA over Vietnamese healthcare regulatory documents. ViHERMES consists of high-quality question-answer pairs that require reasoning across multiple regulations and capture diverse dependency patterns, including amendment tracing, cross-document comparison, and procedural synthesis. To construct the dataset, we propose a controlled multihop QA generation pipeline based on semantic clustering and graph-inspired data mining, followed by large language model-based generation with structured evidence and reasoning annotations. We further present a graph-aware retrieval framework that models formal legal relations at the level of legal units and supports principled context expansion for legally valid and coherent answers. Experimental results demonstrate that ViHERMES provides a challenging benchmark for evaluating multihop regulatory QA systems and that the proposed graph-aware approach consistently outperforms strong retrieval-based baselines. The ViHERMES dataset and system implementation are publicly available at https://github.com/ura-hcmut/ViHERMES.
[16] MTR-DuplexBench: Towards a Comprehensive Evaluation of Multi-Round Conversations for Full-Duplex Speech Language Models
He Zhang, Wenqian Cui, Haoning Xu, Xiaohui Li, Lei Zhu, Haoli Bai, Shaohua Ma, Irwin King
Main category: cs.CL
TL;DR: MTR-DuplexBench is a new benchmark for evaluating Full-Duplex Speech Language Models in multi-round conversational settings, addressing gaps in existing single-round evaluation methods.
Details
Motivation: Existing benchmarks for Full-Duplex Speech Language Models focus on single-round interactions and neglect multi-round communication complexities, including blurred turn boundaries and context inconsistency. Current evaluations also overlook critical aspects beyond conversational features.Method: Introduces MTR-DuplexBench that segments continuous full-duplex dialogues into discrete turns for turn-by-turn assessment and incorporates multiple evaluation dimensions including conversational features, dialogue quality, instruction following, and safety.
Result: Experimental results show current FD-SLMs struggle to maintain consistent performance across multiple rounds and evaluation dimensions, demonstrating the necessity and effectiveness of the proposed benchmark.
Conclusion: MTR-DuplexBench addresses critical gaps in FD-SLM evaluation by enabling comprehensive multi-round assessment across multiple dimensions, revealing current model limitations and providing a more realistic evaluation framework.
Abstract: Full-Duplex Speech Language Models (FD-SLMs) enable real-time, overlapping conversational interactions, offering a more dynamic user experience compared to traditional half-duplex models. However, existing benchmarks primarily focus on evaluating single-round interactions, neglecting the complexities of multi-round communication. Evaluating FD-SLMs in multi-round settings poses significant challenges, including blurred turn boundaries in communication and context inconsistency during model inference. Also, existing benchmarks often focus solely on evaluating conversational features, neglecting other critical aspects. To address these gaps, we introduce MTR-DuplexBench, a novel benchmark designed for a comprehensive multi-round evaluation of FD-SLMs. MTR-DuplexBench not only segments continuous full-duplex dialogues into discrete turns for turn-by-turn assessment but also incorporates various evaluation aspects, including conversational features, dialogue quality, instruction following, and safety. Experimental results reveal that current FD-SLMs face difficulties in maintaining consistent performance across multiple rounds and evaluation dimensions, highlighting the necessity and effectiveness of our benchmark. The benchmark and code will be available in the future.
[17] TernaryLM: Memory-Efficient Language Modeling via Native 1-Bit Quantization with Adaptive Layer-wise Scaling
Nisharg Nargund, Priyesh Shukla
Main category: cs.CL
TL;DR: TernaryLM: A 132M parameter transformer using native 1-bit ternary quantization {-1, 0, +1} during training for memory-efficient language modeling without sacrificing performance.
Details
Motivation: Large language models require substantial computational resources, limiting deployment on edge devices and resource-constrained environments. There's a need for efficient models that maintain performance while reducing memory footprint.Method: TernaryLM employs native 1-bit ternary quantization {-1, 0, +1} during training (not post-training), using straight-through estimators and adaptive per-layer scaling factors to learn quantization-aware representations from scratch.
Result: Achieves 58.42 perplexity on TinyStories, 82.47% F1 on MRPC paraphrase detection, 2.4x memory reduction (498MB vs 1197MB) with comparable inference latency, and stable training across diverse corpora.
Conclusion: Native 1-bit training is a promising direction for efficient neural language models, with middle transformer layers showing highest compatibility with extreme quantization, informing future non-uniform precision strategies.
Abstract: Large language models (LLMs) achieve remarkable performance but demand substantial computational resources, limiting deployment on edge devices and resource-constrained environments. We present TernaryLM, a 132M parameter transformer architecture that employs native 1-bit ternary quantization {-1, 0, +1} during training, achieving significant memory reduction without sacrificing language modeling capability. Unlike post-training quantization approaches that quantize pre-trained full-precision models, TernaryLM learns quantization-aware representations from scratch using straight-through estimators and adaptive per-layer scaling factors. Our experiments demonstrate: (1) validation perplexity of 58.42 on TinyStories; (2) downstream transfer with 82.47 percent F1 on MRPC paraphrase detection; (3) 2.4x memory reduction (498MB vs 1197MB) with comparable inference latency; and (4) stable training dynamics across diverse corpora. We provide layer-wise quantization analysis showing that middle transformer layers exhibit highest compatibility with extreme quantization, informing future non-uniform precision strategies. Our results suggest that native 1-bit training is a promising direction for efficient neural language models. Code is available at https://github.com/1nisharg/TernaryLM-Memory-Efficient-Language-Modeling.
[18] Efficient Post-Training Pruning of Large Language Models with Statistical Correction
Peiqi Yu, Jinhao Wang, Xinyi Sui, Nam Ling, Wei Wang, Wei Jiang
Main category: cs.CL
TL;DR: A lightweight post-training pruning framework for LLMs using first-order statistical properties to calibrate importance scores and apply energy compensation, achieving better performance than heuristic methods with similar computational efficiency.
Details
Motivation: Existing post-training pruning methods face a trade-off between quality and efficiency: heuristic methods are efficient but sensitive to activation outliers, while reconstruction-based approaches improve fidelity at high computational cost.Method: Proposes a pruning framework based on first-order statistical properties of weights and activations. Uses channel-wise statistics to calibrate magnitude-based importance scores, reducing bias from activation-dominated channels. After pruning, applies analytic energy compensation to correct distributional distortions from weight removal. Both steps operate without retraining, gradients, or second-order information.
Result: Experiments across multiple LLM families, sparsity patterns, and evaluation tasks show improved pruning performance while maintaining computational cost comparable to heuristic methods.
Conclusion: Simple statistical corrections can be effective for post-training pruning of LLMs, offering a better balance between quality and efficiency than existing approaches.
Abstract: Post-training pruning is an effective approach for reducing the size and inference cost of large language models (LLMs), but existing methods often face a trade-off between pruning quality and computational efficiency. Heuristic pruning methods are efficient but sensitive to activation outliers, while reconstruction-based approaches improve fidelity at the cost of heavy computation. In this work, we propose a lightweight post-training pruning framework based on first-order statistical properties of model weights and activations. During pruning, channel-wise statistics are used to calibrate magnitude-based importance scores, reducing bias from activation-dominated channels. After pruning, we apply an analytic energy compensation to correct distributional distortions caused by weight removal. Both steps operate without retraining, gradients, or second-order information. Experiments across multiple LLM families, sparsity patterns, and evaluation tasks show that the proposed approach improves pruning performance while maintaining computational cost comparable to heuristic methods. The results suggest that simple statistical corrections can be effective for post-training pruning of LLMs.
[19] Do Large Language Models Reflect Demographic Pluralism in Safety?
Usman Naseem, Gautam Siddharth Kashyap, Sushant Kumar Ray, Rafiq Ali, Ebad Shabbir, Abdullah Mohammad
Main category: cs.CL
TL;DR: Demo-SafetyBench introduces a pluralistic safety evaluation benchmark that incorporates demographic diversity into LLM safety assessment by reclassifying prompts into safety domains and evaluating with demographic-aware metrics.
Details
Motivation: Existing LLM safety alignment datasets like ANTHROPIC-HH and DICES use demographically narrow annotator pools, overlooking variations in safety perceptions across different communities and cultural contexts. There's a need for safety evaluation that accounts for demographic pluralism.Method: Two-stage approach: Stage I reclassifies DICES prompts into 14 safety domains using Mistral 7B-Instruct-v0.3, retains demographic metadata, and expands low-resource domains via Llama-3.1-8B-Instruct with SimHash deduplication (43,050 samples). Stage II evaluates pluralistic sensitivity using LLMs-as-Raters (Gemma-7B, GPT-4o, LLaMA-2-7B) with zero-shot inference and balanced thresholds.
Result: Achieved high reliability (ICC = 0.87) and low demographic sensitivity (DS = 0.12) with balanced thresholds (delta = 0.5, tau = 10), demonstrating that pluralistic safety evaluation can be both scalable and demographically robust.
Conclusion: Demo-SafetyBench successfully addresses the demographic narrowness in existing safety benchmarks by modeling pluralism at the prompt level, showing that scalable, demographically-aware safety evaluation is feasible and reliable.
Abstract: Large Language Model (LLM) safety is inherently pluralistic, reflecting variations in moral norms, cultural expectations, and demographic contexts. Yet, existing alignment datasets such as ANTHROPIC-HH and DICES rely on demographically narrow annotator pools, overlooking variation in safety perception across communities. Demo-SafetyBench addresses this gap by modeling demographic pluralism directly at the prompt level, decoupling value framing from responses. In Stage I, prompts from DICES are reclassified into 14 safety domains (adapted from BEAVERTAILS) using Mistral 7B-Instruct-v0.3, retaining demographic metadata and expanding low-resource domains via Llama-3.1-8B-Instruct with SimHash-based deduplication, yielding 43,050 samples. In Stage II, pluralistic sensitivity is evaluated using LLMs-as-Raters-Gemma-7B, GPT-4o, and LLaMA-2-7B-under zero-shot inference. Balanced thresholds (delta = 0.5, tau = 10) achieve high reliability (ICC = 0.87) and low demographic sensitivity (DS = 0.12), confirming that pluralistic safety evaluation can be both scalable and demographically robust.
[20] When the Model Said ‘No Comment’, We Knew Helpfulness Was Dead, Honesty Was Alive, and Safety Was Terrified
Gautam Siddharth Kashyap, Mark Dras, Usman Naseem
Main category: cs.CL
TL;DR: AlignX: A two-stage framework for aligning LLMs with human values (HHH) that addresses axis collapse through prompt-injected fine-tuning and calibrated MoE routing
Details
Motivation: Existing alignment methods (SFT and MoE) face challenges in multi-objective settings: SFT causes interference between conflicting objectives, while MoEs suffer from miscalibrated routing, leading to axis collapse with disjoint feature spaces and unreliable inferenceMethod: Two-stage framework: Stage 1 uses prompt-injected fine-tuning to extract axis-specific task features, mitigating catastrophic forgetting. Stage 2 deploys MoCaE module that calibrates expert routing using fractal and natural geometry for improved inference reliability
Result: Significant gains on Alpaca (+171.5% win rate for helpfulness), BeaverTails (fewer safety violations), and TruthfulQA (+110.1% in truthfulness-informativeness). Reduces latency and memory usage by over 35% compared to prior MoEs. Validated across four LLMs
Conclusion: AlignX effectively addresses axis collapse in multi-objective LLM alignment, improving performance on HHH metrics while reducing computational overhead, demonstrating generalizability across different LLMs
Abstract: Large Language Models (LLMs) need to be in accordance with human values-being helpful, harmless, and honest (HHH)-is important for safe deployment. Existing works use Supervised Fine-Tuning (SFT) and Mixture-of-Experts (MoE) to align LLMs. However, these works face challenges in multi-objective settings, such as SFT leading to interference between conflicting objectives, while MoEs suffer from miscalibrated routing. We term this failure mode Axis Collapse, marked by (1) disjoint feature spaces causing catastrophic forgetting, and (2) unreliable inference from misrouted experts. To resolve this, we propose AlignX, a two-stage framework. Stage 1 uses prompt-injected fine-tuning to extract axis-specific task features, mitigating catastrophic forgetting. Stage 2 deploys a MoCaE module that calibrates expert routing using fractal and natural geometry, improving inference reliability. AlignX achieves significant gains on Alpaca (Helpfulness), BeaverTails (Harmlessness), and TruthfulQA (Honesty), with +171.5% win rate, +110.1% in truthfulness-informativeness, and 4.3% fewer safety violations. It also reduces latency and memory usage by over 35% compared to prior MoEs. Results across four LLMs validate its generalizability.
[21] Advantages of Domain Knowledge Injection for Legal Document Summarization: A Case Study on Summarizing Indian Court Judgments in English and Hindi
Debtanu Datta, Rajdeep Mukherjee, Adrijit Goswami, Saptarshi Ghosh
Main category: cs.CL
TL;DR: Improving Indian legal document summarization in English and Hindi by injecting legal domain knowledge into neural summarization models and LLMs through domain-specific encoders and continual pre-training.
Details
Motivation: Indian legal court judgments are complex due to intricate language and unstructured nature, and a large population doesn't understand the complex English used in legal texts, requiring summaries in Indian languages like Hindi.Method: 1) Enhanced extractive neural summarization models by incorporating domain-specific pre-trained encoders for legal texts. 2) Injected legal domain knowledge into generative models (including LLMs) through continual pre-training on large legal corpora in English and Hindi.
Result: Achieved statistically significant improvements in both English-to-English and English-to-Hindi Indian legal document summarization, measured by standard evaluation metrics, factual consistency metrics, and legal domain-specific metrics, validated by domain experts.
Conclusion: The proposed approaches effectively improve legal text summarization for Indian contexts by incorporating domain knowledge, addressing both language complexity and accessibility issues for non-English speaking populations.
Abstract: Summarizing Indian legal court judgments is a complex task not only due to the intricate language and unstructured nature of the legal texts, but also since a large section of the Indian population does not understand the complex English in which legal text is written, thus requiring summaries in Indian languages. In this study, we aim to improve the summarization of Indian legal text to generate summaries in both English and Hindi (the most widely spoken Indian language), by injecting domain knowledge into diverse summarization models. We propose a framework to enhance extractive neural summarization models by incorporating domain-specific pre-trained encoders tailored for legal texts. Further, we explore the injection of legal domain knowledge into generative models (including Large Language Models) through continual pre-training on large legal corpora in English and Hindi. Our proposed approaches achieve statistically significant improvements in both English-to-English and English-to-Hindi Indian legal document summarization, as measured by standard evaluation metrics, factual consistency metrics, and legal domain-specific metrics. Furthermore, these improvements are validated through domain experts, demonstrating the effectiveness of our approaches.
[22] Emotion-Aligned Generation in Diffusion Text to Speech Models via Preference-Guided Optimization
Jiacheng Shi, Hongfei Du, Yangfan He, Y. Alicia Hong, Ye Gao
Main category: cs.CL
TL;DR: EASPO is a post-training framework that aligns diffusion TTS with fine-grained emotional preferences at intermediate denoising steps using stepwise preference optimization.
Details
Motivation: Existing emotional text-to-speech methods rely on coarse labels or proxy classifiers and only receive utterance-level feedback, limiting their ability to convey nuanced emotional expression while preserving intelligibility and prosody.Method: Introduces Emotion-Aware Stepwise Preference Optimization (EASPO) with EASPM, a time-conditioned model that scores noisy intermediate speech states to enable automatic preference pair construction and stepwise preference optimization for controllable emotional shaping.
Result: Experiments show superior performance over existing methods in both expressiveness and naturalness for emotional TTS generation.
Conclusion: EASPO enables more fine-grained emotional control in TTS systems through stepwise preference optimization, advancing emotional speech synthesis capabilities.
Abstract: Emotional text-to-speech seeks to convey affect while preserving intelligibility and prosody, yet existing methods rely on coarse labels or proxy classifiers and receive only utterance-level feedback. We introduce Emotion-Aware Stepwise Preference Optimization (EASPO), a post-training framework that aligns diffusion TTS with fine-grained emotional preferences at intermediate denoising steps. Central to our approach is EASPM, a time-conditioned model that scores noisy intermediate speech states and enables automatic preference pair construction. EASPO optimizes generation to match these stepwise preferences, enabling controllable emotional shaping. Experiments show superior performance over existing methods in both expressiveness and naturalness.
[23] Measuring cross-language intelligibility between Romance languages with computational tools
Liviu P Dinu, Ana Sabina Uban, Bogdan Iordache, Anca Dinu, Simona Georgescu
Main category: cs.CL
TL;DR: Computational analysis of mutual intelligibility in Romance languages using lexical similarity metrics based on orthographic/phonetic forms and semantic representations, validated against human experiments.
Details
Motivation: To develop computational methods for measuring mutual intelligibility between related languages, specifically focusing on Romance languages, and validate these methods against human comprehension tests.Method: Introduces a novel computational metric using lexical similarity based on both surface (orthographic/phonetic) and semantic similarity of related words. Applies this to five main Romance languages using different parallel corpora and word embedding models.
Result: The computational intelligibility scores confirm intuitions about intelligibility asymmetry across Romance languages and show significant correlation with results from human cloze tests.
Conclusion: Computational methods using lexical similarity can effectively estimate mutual intelligibility between related languages, providing results that align with human comprehension patterns.
Abstract: We present an analysis of mutual intelligibility in related languages applied for languages in the Romance family. We introduce a novel computational metric for estimating intelligibility based on lexical similarity using surface and semantic similarity of related words, and use it to measure mutual intelligibility for the five main Romance languages (French, Italian, Portuguese, Spanish, and Romanian), and compare results using both the orthographic and phonetic forms of words as well as different parallel corpora and vectorial models of word meaning representation. The obtained intelligibility scores confirm intuitions related to intelligibility asymmetry across languages and significantly correlate with results of cloze tests in human experiments.
[24] DLLM Agent: See Farther, Run Faster
Huiling Zhen, Weizhe Lin, Renxi Liu, Kai Han, Yiming Li, Yuchuan Tian, Hanting Chen, Xiaoguang Li, Xiaosong Li, Chen Chen, Xianzhi Yu, Mingxuan Yuan, Youliang Yan, Peifeng Qin, Jun Wang, Yu Wang, Dacheng Tao, Yunhe Wang
Main category: cs.CL
TL;DR: Diffusion LLMs in agent workflows show 30%+ faster end-to-end execution than autoregressive agents with comparable accuracy, requiring fewer tool invocations and showing stronger planning signals.
Details
Motivation: To explore whether diffusion-based LLMs induce systematically different planning and tool-use behaviors compared to autoregressive LLMs in agentic multi-step decision making, and whether these differences translate to practical efficiency gains.Method: Created DLLM and AR backbones within the same DeepDiver agent workflow, performed matched agent-oriented fine-tuning on identical trajectory data, and compared diffusion-backed DLLM Agents with directly comparable AR agents across benchmarks and case studies.
Result: DLLM Agents are on average over 30% faster end-to-end than AR agents (some cases exceeding 8x speedup), require fewer interaction rounds and tool invocations, show higher planner hit rates, and converge earlier to correct action paths with less backtracking.
Conclusion: Diffusion backbones offer significant efficiency advantages for agentic decision making but require careful handling of tool-call failures and attention masking for multi-turn inputs to achieve optimal performance.
Abstract: Diffusion large language models (DLLMs) have emerged as an alternative to autoregressive (AR) decoding with appealing efficiency and modeling properties, yet their implications for agentic multi-step decision making remain underexplored. We ask a concrete question: when the generation paradigm is changed but the agent framework and supervision are held fixed, do diffusion backbones induce systematically different planning and tool-use behaviors, and do these differences translate into end-to-end efficiency gains? We study this in a controlled setting by instantiating DLLM and AR backbones within the same agent workflow (DeepDiver) and performing matched agent-oriented fine-tuning on the same trajectory data, yielding diffusion-backed DLLM Agents and directly comparable AR agents. Across benchmarks and case studies, we find that, at comparable accuracy, DLLM Agents are on average over 30% faster end to end than AR agents, with some cases exceeding 8x speedup. Conditioned on correct task completion, DLLM Agents also require fewer interaction rounds and tool invocations, consistent with higher planner hit rates that converge earlier to a correct action path with less backtracking. We further identify two practical considerations for deploying diffusion backbones in tool-using agents. First, naive DLLM policies are more prone to structured tool-call failures, necessitating stronger tool-call-specific training to emit valid schemas and arguments. Second, for multi-turn inputs interleaving context and action spans, diffusion-style span corruption requires aligned attention masking to avoid spurious context-action information flow; without such alignment, performance degrades. Finally, we analyze attention dynamics across workflow stages and observe paradigm-specific coordination patterns, suggesting stronger global planning signals in diffusion-backed agents.
[25] SED-SFT: Selectively Encouraging Diversity in Supervised Fine-Tuning
Yijie Chen, Yijin Liu, Fandong Meng
Main category: cs.CL
TL;DR: SED-SFT addresses mode collapse in supervised fine-tuning of LLMs by introducing selective entropy regularization to enhance response diversity for better RL performance.
Details
Motivation: Standard SFT using cross-entropy loss causes mode collapse, where models over-concentrate on specific response patterns, reducing diversity needed for effective RL exploration.Method: Proposes SED-SFT with selective entropy regularization and masking mechanism that adaptively encourages diversity based on token exploration space while maintaining accuracy.
Result: Significantly improves generation diversity with minimal computational overhead, yielding average gains of 2.06 and 1.20 points in RL performance on Llama-3.2-3B-Instruct and Qwen2.5-Math-7B-Instruct across eight mathematical benchmarks.
Conclusion: SED-SFT effectively balances diversity and accuracy in SFT, addressing mode collapse and improving subsequent RL performance in LLM training pipelines.
Abstract: Supervised Fine-Tuning (SFT) followed by Reinforcement Learning (RL) has emerged as the standard post-training paradigm for large language models (LLMs). However, the conventional SFT process, driven by Cross-Entropy (CE) loss, often induces mode collapse, where models over-concentrate on specific response patterns. This lack of distributional diversity severely restricts the exploration efficiency required for subsequent RL. While recent studies have attempted to improve SFT by replacing the CE loss, aiming to preserve diversity or refine the update policy, they fail to adequately balance diversity and accuracy, thereby yielding suboptimal performance after RL. To address the mode collapse problem, we propose SED-SFT, which adaptively encourages diversity based on the token exploration space. This framework introduces a selective entropy regularization term with a selective masking mechanism into the optimization objective. Extensive experiments across eight mathematical benchmarks demonstrate that SED-SFT significantly enhances generation diversity with a negligible computational overhead increase compared with CE loss, yielding average improvements of 2.06 and 1.20 points in subsequent RL performance over standard CE-based baselines on Llama-3.2-3B-Instruct and Qwen2.5-Math-7B-Instruct, respectively. The code is publicly available at https://github.com/pppa2019/SED-SFT
[26] From Native Memes to Global Moderation: Cros-Cultural Evaluation of Vision-Language Models for Hateful Meme Detection
Mo Wang, Kaixuan Ren, Pratik Jalan, Ahmed Ashraf, Tuong Vy Vu, Rahul Seetharaman, Shah Nawaz, Usman Naseem
Main category: cs.CL
TL;DR: VLMs trained with Western/English bias perform poorly on cross-cultural hateful meme detection; native-language prompting and one-shot learning improve performance, while translation approaches degrade it.
Details
Motivation: Vision-language models (VLMs) are predominantly trained through Western or English-centric lenses, limiting their fairness and cross-cultural robustness in tasks like hateful meme detection, where cultural context profoundly shapes interpretation.Method: Introduced systematic evaluation framework to diagnose cross-cultural robustness of VLMs across multilingual meme datasets, analyzing three axes: (i) learning strategy (zero-shot vs. one-shot), (ii) prompting language (native vs. English), and (iii) translation effects on meaning and detection.
Result: Common “translate-then-detect” approach deteriorates performance, while culturally aligned interventions - native-language prompting and one-shot learning - significantly enhance detection. Reveals systematic convergence toward Western safety norms.
Conclusion: Provides actionable strategies to mitigate cultural bias in VLMs and guides design of globally robust multimodal moderation systems through culturally aligned interventions.
Abstract: Cultural context profoundly shapes how people interpret online content, yet vision-language models (VLMs) remain predominantly trained through Western or English-centric lenses. This limits their fairness and cross-cultural robustness in tasks like hateful meme detection. We introduce a systematic evaluation framework designed to diagnose and quantify the cross-cultural robustness of state-of-the-art VLMs across multilingual meme datasets, analyzing three axes: (i) learning strategy (zero-shot vs. one-shot), (ii) prompting language (native vs. English), and (iii) translation effects on meaning and detection. Results show that the common ``translate-then-detect’’ approach deteriorate performance, while culturally aligned interventions - native-language prompting and one-shot learning - significantly enhance detection. Our findings reveal systematic convergence toward Western safety norms and provide actionable strategies to mitigate such bias, guiding the design of globally robust multimodal moderation systems.
[27] Let’s Simplify Step by Step: Guiding LLM Towards Multilingual Unsupervised Proficiency-Controlled Sentence Simplification
Jingshen Zhang, Xin Ying Qiu, Lifang Lu, Zhuhua Huang, Yutao Hu, Yuechang Wu, JunYu Lu
Main category: cs.CL
TL;DR: Framework for proficiency-controlled sentence simplification using dynamic path planning, semantic-aware exemplar selection, and chain-of-thought generation to break complex simplifications into manageable steps across multiple languages.
Details
Motivation: Large language models have limited capability in proficiency-controlled sentence simplification, especially when simplifying across large readability levels. There's a need for better approaches that can handle complex simplifications while maintaining control over the simplification process.Method: Proposes a framework that decomposes complex simplifications into manageable steps through: 1) dynamic path planning, 2) semantic-aware exemplar selection, and 3) chain-of-thought generation with conversation history for coherent reasoning.
Result: Evaluation on five languages across two benchmarks shows the approach improves simplification effectiveness while reducing computational steps by 22-42%. Human evaluation reveals fundamental trade-off between simplification effectiveness and meaning preservation, with even human annotators struggling to agree on semantic preservation judgments.
Conclusion: While step-by-step simplification improves control over the simplification process, preserving semantic fidelity during extensive simplification remains an open challenge, highlighting the inherent complexity of this task.
Abstract: Large language models demonstrate limited capability in proficiency-controlled sentence simplification, particularly when simplifying across large readability levels. We propose a framework that decomposes complex simplifications into manageable steps through dynamic path planning, semantic-aware exemplar selection, and chain-of-thought generation with conversation history for coherent reasoning. Evaluation on five languages across two benchmarks shows our approach improves simplification effectiveness while reducing computational steps by 22-42%. Human evaluation confirms the fundamental trade-off between simplification effectiveness and meaning preservation. Notably, even human annotators struggle to agree on semantic preservation judgments, highlighting the inherent complexity of this task. Our work shows that while step-by-step simplification improves control, preserving semantic fidelity during extensive simplification remains an open challenge.
[28] Improving Variable-Length Generation in Diffusion Language Models via Length Regularization
Zicong Cheng, Ruixuan Jia, Jia Li, Guo-Wei Yang, Meng-Hao Guo, Shi-Min Hu
Main category: cs.CL
TL;DR: LR-DLLM is a length-regularized inference framework for Diffusion Large Language Models that addresses variable-length generation challenges by treating length as an explicit variable and correcting biased confidence estimates.
Details
Motivation: Diffusion LLMs are inherently ill-suited for variable-length generation due to fixed-length canvas assumptions and systematic biases in confidence estimates across mask lengths, making realistic completion and infilling unreliable when target length is unknown.Method: Proposes LR-DLLM framework that treats generation length as an explicit variable, decouples semantic compatibility from length-induced uncertainty through explicit length regularization, and enables dynamic expansion/contraction of generation spans without modifying the underlying DLLM or training procedure.
Result: Achieves 51.3% Pass@1 on HumanEvalInfilling under fully unknown lengths (+13.4% vs. DreamOn) and 51.5% average Pass@1 on four-language McEval (+14.3% vs. DreamOn).
Conclusion: LR-DLLM provides a robust solution for variable-length inference in Diffusion LLMs by addressing intrinsic length-induced biases in confidence estimates, enabling reliable length determination at inference time.
Abstract: Diffusion Large Language Models (DLLMs) are inherently ill-suited for variable-length generation, as their inference is defined on a fixed-length canvas and implicitly assumes a known target length. When the length is unknown, as in realistic completion and infilling, naively comparing confidence across mask lengths becomes systematically biased, leading to under-generation or redundant continuations. In this paper, we show that this failure arises from an intrinsic lengthinduced bias in generation confidence estimates, leaving existing DLLMs without a robust way to determine generation length and making variablelength inference unreliable. To address this issue, we propose LR-DLLM, a length-regularized inference framework for DLLMs that treats generation length as an explicit variable and achieves reliable length determination at inference time. It decouples semantic compatibility from lengthinduced uncertainty through an explicit length regularization that corrects biased confidence estimates. Based on this, LR-DLLM enables dynamic expansion or contraction of the generation span without modifying the underlying DLLM or its training procedure. Experiments show that LRDLLM achieves 51.3% Pass@1 on HumanEvalInfilling under fully unknown lengths (+13.4% vs. DreamOn) and 51.5% average Pass@1 on four-language McEval (+14.3% vs. DreamOn).
[29] Learning to Self-Verify Makes Language Models Better Reasoners
Yuxin Chen, Yu Wang, Yi Zhang, Ziang Ye, Zhengzhou Cai, Yaorui Shi, Qi Gu, Hui Su, Xunliang Cai, Xiang Wang, An Zhang, Tat-Seng Chua
Main category: cs.CL
TL;DR: LLMs show capability asymmetry: strong generation but weak self-verification. Learning to self-verify improves generation, but improving generation doesn’t improve verification. Multi-task RL framework integrates both objectives for better performance.
Details
Motivation: Large language models excel at generating reasoning paths but struggle with self-verification, creating a persistent capability asymmetry. The authors investigate this asymmetry and explore whether improving one capability can benefit the other.Method: Analyze training evolution to study generation-verification asymmetry. Develop multi-task reinforcement learning framework where generation and self-verification are optimized as independent but complementary objectives. Conduct extensive experiments across benchmarks and models.
Result: Learning to self-verify effectively improves generation performance, achieving comparable accuracy to standard generation training while producing more efficient reasoning traces. Multi-task RL framework outperforms generation-only training in both generation and verification capabilities.
Conclusion: Self-verification can enhance generation capabilities, and integrating both objectives through multi-task RL leads to better overall performance. The asymmetry is directional: verification helps generation more than generation helps verification.
Abstract: Recent large language models (LLMs) achieve strong performance in generating promising reasoning paths for complex tasks. However, despite powerful generation ability, LLMs remain weak at verifying their own answers, revealing a persistent capability asymmetry between generation and self-verification. In this work, we conduct an in-depth investigation of this asymmetry throughout training evolution and show that, even on the same task, improving generation does not lead to corresponding improvements in self-verification. Interestingly, we find that the reverse direction of this asymmetry behaves differently: learning to self-verify can effectively improve generation performance, achieving accuracy comparable to standard generation training while yielding more efficient and effective reasoning traces. Building on this observation, we further explore integrating self-verification into generation training by formulating a multi-task reinforcement learning framework, where generation and self-verification are optimized as two independent but complementary objectives. Extensive experiments across benchmarks and models demonstrate performance gains over generation-only training in both generation and verification capabilities.
[30] SciClaimEval: Cross-modal Claim Verification in Scientific Papers
Xanh Ho, Yun-Ang Wu, Sunisth Kumar, Tian Cheng Xia, Florian Boudin, Andre Greiner-Petter, Akiko Aizawa
Main category: cs.CL
TL;DR: SciClaimEval is a new scientific dataset for multimodal claim verification featuring authentic claims extracted from published papers, with refuted claims created by modifying supporting evidence (figures/tables) rather than altering claims or using LLMs.
Details
Motivation: Existing claim verification datasets lack authentic scientific claims with refuted examples. Current approaches often fabricate contradictions using LLMs or modify claims directly, which doesn't reflect real-world scientific verification scenarios where evidence might be misinterpreted or manipulated.Method: Created dataset by extracting authentic claims from published papers across ML, NLP, and medicine. For refuted claims, modified supporting evidence (figures and tables) rather than altering claims. Dataset includes cross-modal evidence with figures as images and tables in multiple formats (images, LaTeX, HTML, JSON). Contains 1,664 annotated samples from 180 papers with expert validation.
Result: Benchmarked 11 multimodal foundation models (open-source and proprietary). Results show figure-based verification remains particularly challenging, with substantial performance gap between best system and human baseline.
Conclusion: SciClaimEval provides a realistic benchmark for scientific claim verification that better reflects real-world scenarios. The dataset highlights current limitations of multimodal models in verifying claims based on visual evidence like figures.
Abstract: We present SciClaimEval, a new scientific dataset for the claim verification task. Unlike existing resources, SciClaimEval features authentic claims, including refuted ones, directly extracted from published papers. To create refuted claims, we introduce a novel approach that modifies the supporting evidence (figures and tables), rather than altering the claims or relying on large language models (LLMs) to fabricate contradictions. The dataset provides cross-modal evidence with diverse representations: figures are available as images, while tables are provided in multiple formats, including images, LaTeX source, HTML, and JSON. SciClaimEval contains 1,664 annotated samples from 180 papers across three domains, machine learning, natural language processing, and medicine, validated through expert annotation. We benchmark 11 multimodal foundation models, both open-source and proprietary, across the dataset. Results show that figure-based verification remains particularly challenging for all models, as a substantial performance gap remains between the best system and human baseline.
[31] Letting Tutor Personas “Speak Up” for LLMs: Learning Steering Vectors from Dialogue via Preference Optimization
Jaewook Lee, Alexander Scarlatos, Simon Woodhead, Andrew Lan
Main category: cs.CL
TL;DR: This paper explores using activation steering vectors to capture diverse tutoring styles in LLM-based tutoring systems, moving beyond single-policy approaches to better reflect real-world pedagogical variation.
Details
Motivation: Current LLM-based tutoring systems typically learn a single tutor policy, failing to capture the diversity of tutoring styles found in real-world tutor-student interactions where pedagogical intent varies through different instructional strategies, scaffolding levels, feedback approaches, and affective support.Method: The authors modify Bidirectional Preference Optimization (BiPO) to learn a steering vector - an activation-space direction that steers model responses toward specific tutor personas. This approach uses tutor personas embedded in human tutor-student dialogues to guide LLM behavior without explicit prompting.
Result: The steering vector captures tutor-specific variation across dialogue contexts, improving semantic alignment with ground-truth tutor utterances and increasing preference-based evaluations while preserving lexical similarity. Analysis reveals interpretable structure across tutors corresponding to consistent differences in tutoring behavior.
Conclusion: Activation steering offers an effective and interpretable way to control tutor-specific variation in LLMs using signals derived directly from human dialogue data, enabling more nuanced and personalized tutoring systems.
Abstract: With the emergence of large language models (LLMs) as a powerful class of generative artificial intelligence (AI), their use in tutoring has become increasingly prominent. Prior works on LLM-based tutoring typically learn a single tutor policy and do not capture the diversity of tutoring styles. In real-world tutor-student interactions, pedagogical intent is realized through adaptive instructional strategies, with tutors varying the level of scaffolding, instructional directiveness, feedback, and affective support in response to learners’ needs. These differences can all impact dialogue dynamics and student engagement. In this paper, we explore how tutor personas embedded in human tutor-student dialogues can be used to guide LLM behavior without relying on explicitly prompted instructions. We modify Bidirectional Preference Optimization (BiPO) to learn a steering vector, an activation-space direction that steers model responses towards certain tutor personas. We find that this steering vector captures tutor-specific variation across dialogue contexts, improving semantic alignment with ground-truth tutor utterances and increasing preference-based evaluations, while largely preserving lexical similarity. Analysis of the learned directional coefficients further reveals interpretable structure across tutors, corresponding to consistent differences in tutoring behavior. These results demonstrate that activation steering offers an effective and interpretable way for controlling tutor-specific variation in LLMs using signals derived directly from human dialogue data.
[32] Blind to the Human Touch: Overlap Bias in LLM-Based Summary Evaluation
Jiangnan Fang, Cheng-Tse Liu, Hanieh Deilamsalehy, Nesreen K. Ahmed, Puneet Mathur, Nedim Lipka, Franck Dernoncourt, Ryan A. Rossi
Main category: cs.CL
TL;DR: LLM judges show systematic biases preferring AI-generated over human-written summaries as similarity metrics decrease, with this pattern persisting across most models tested despite position biases.
Details
Motivation: While LLM judges are increasingly used for summarization evaluation due to their semantic understanding and reasoning capabilities, they exhibit biases for length, order, and vulnerability to adversarial prompts. However, granular analysis of these biases in relation to overlap metrics with human-written responses is lacking.Method: Conducted bias analysis of LLM judges as a function of overlap with human-written responses in summarization domain. Tested 9 recent LLMs (1B to 12B parameters) including Gemma 3 and LLaMA 3 variants, measuring preferences between AI-generated and human-written summaries based on ROUGE and BLEU similarity metrics.
Result: LLM judges increasingly prefer AI-generated summaries over human-written ones as ROUGE/BLEU similarities decrease. This pattern extends to all but one model tested and persists regardless of models’ own position biases. Models struggle to judge summaries even with limited overlaps.
Conclusion: LLM-as-a-judge in summarization should rely on techniques beyond simple comparison due to systematic biases. The findings highlight limitations of current LLM evaluation methods and suggest need for more sophisticated approaches.
Abstract: Large language model (LLM) judges have often been used alongside traditional, algorithm-based metrics for tasks like summarization because they better capture semantic information, are better at reasoning, and are more robust to paraphrasing. However, LLM judges show biases for length and order among others, and are vulnerable to various adversarial input prompts. While recent studies have looked into these biases, few have analyzed them at a more granular level in relation to a well-defined overlap metric. In this work we provide an LLM judge bias analysis as a function of overlap with human-written responses in the domain of summarization. We test 9 recent LLMs with parameter counts ranging from 1 billion to 12 billion, including variants of Gemma 3 and LLaMA 3. We find that LLM judges increasingly prefer summaries generated by other LLMs over those written by humans as the similarities (as measured by ROUGE and BLEU) between the judged summaries decrease, and this pattern extends to all but one model tested, and exists regardless of the models’ own position biases. Additionally, we find that models struggle to judge even summaries with limited overlaps, suggesting that LLM-as-a-judge in the summary domain should rely on techniques beyond a simple comparison.
[33] SRR-Judge: Step-Level Rating and Refinement for Enhancing Search-Integrated Reasoning in Search Agents
Chen Zhang, Kuicai Dong, Dexun Li, Wenjun Li, Qu Yang, Wei Han, Yong Liu
Main category: cs.CL
TL;DR: SRR-Judge framework provides step-level assessment for search-integrated reasoning in deep search agents, enabling better training through fine-grained guidance and iterative rejection sampling.
Details
Motivation: Current deep search agents trained with outcome-based supervision neglect intermediate reasoning quality, leading to suboptimal search-integrated reasoning capabilities.Method: Introduces SRR-Judge framework for reliable step-level assessment, integrates into ReAct-style workflow for fine-grained guidance, uses iterative rejection sampling fine-tuning with SRR-annotated data.
Result: SRR-Judge outperforms larger models like DeepSeek-V3.1 in step-level evaluation reliability, shows strong correlation with final answer correctness, and yields over 10% average absolute pass@1 improvement on deep search benchmarks.
Conclusion: Step-level assessment via SRR-Judge significantly enhances deep search agent performance by providing better training supervision for search-integrated reasoning.
Abstract: Recent deep search agents built on large reasoning models (LRMs) excel at complex question answering by iteratively planning, acting, and gathering evidence, a capability known as search-integrated reasoning. However, mainstream approaches often train this ability using only outcome-based supervision, neglecting the quality of intermediate thoughts and actions. We introduce SRR-Judge, a framework for reliable step-level assessment of reasoning and search actions. Integrated into a modified ReAct-style rate-and-refine workflow, SRR-Judge provides fine-grained guidance for search-integrated reasoning and enables efficient post-training annotation. Using SRR-annotated data, we apply an iterative rejection sampling fine-tuning procedure to enhance the deep search capability of the base agent. Empirically, SRR-Judge delivers more reliable step-level evaluations than much larger models such as DeepSeek-V3.1, with its ratings showing strong correlation with final answer correctness. Moreover, aligning the policy with SRR-Judge annotated trajectories leads to substantial performance gains, yielding over a 10 percent average absolute pass@1 improvement across challenging deep search benchmarks.
[34] Attn-GS: Attention-Guided Context Compression for Efficient Personalized LLMs
Shenglai Zeng, Tianqi Zheng, Chuan Tian, Dante Everaert, Yau-Shian Wang, Yupin Huang, Michael J. Morais, Rohit Patki, Jinjin Tian, Xinnan Dai, Kai Guo, Monica Xiao Cheng, Hui Liu
Main category: cs.CL
TL;DR: Attn-GS: An attention-guided framework for compressing user contexts in LLM personalization by leveraging attention patterns to identify important personalization signals, reducing token usage by 50x while maintaining performance.
Details
Motivation: Personalizing LLMs requires extensive user interaction histories and profiles, but input token constraints cause high inference latency and API costs. Existing heuristic methods for context compression treat context as monolithic and fail to consider how LLMs internally process and prioritize different profile components.Method: Proposes Attn-GS, an attention-guided context compression framework that: 1) Uses attention patterns from a marking model to identify important personalization sentences, 2) Guides a compression model to generate task-relevant, high-quality compressed user contexts based on these attention signals.
Result: Extensive experiments show Attn-GS significantly outperforms various baselines across different tasks, token limits, and settings, achieving performance close to using full context while reducing token usage by 50 times.
Conclusion: LLMs’ attention patterns can effectively identify important personalization signals for intelligent context compression, and fine-tuning enhances LLMs’ ability to distinguish relevant from irrelevant information, enabling efficient personalization with dramatically reduced token usage.
Abstract: Personalizing large language models (LLMs) to individual users requires incorporating extensive interaction histories and profiles, but input token constraints make this impractical due to high inference latency and API costs. Existing approaches rely on heuristic methods such as selecting recent interactions or prompting summarization models to compress user profiles. However, these methods treat context as a monolithic whole and fail to consider how LLMs internally process and prioritize different profile components. We investigate whether LLMs’ attention patterns can effectively identify important personalization signals for intelligent context compression. Through preliminary studies on representative personalization tasks, we discover that (a) LLMs’ attention patterns naturally reveal important signals, and (b) fine-tuning enhances LLMs’ ability to distinguish between relevant and irrelevant information. Based on these insights, we propose Attn-GS, an attention-guided context compression framework that leverages attention feedback from a marking model to mark important personalization sentences, then guides a compression model to generate task-relevant, high-quality compressed user contexts. Extensive experiments demonstrate that Attn-GS significantly outperforms various baselines across different tasks, token limits, and settings, achieving performance close to using full context while reducing token usage by 50 times.
[35] Emergent Structured Representations Support Flexible In-Context Inference in Large Language Models
Ningyu Xu, Qi Zhang, Xipeng Qiu, Xuanjing Huang
Main category: cs.CL
TL;DR: LLMs develop structured conceptual representations in middle-to-late layers that are functionally central to in-context inference, with early layers building these representations and later layers using them for predictions.
Details
Motivation: While LLMs show emergent reasoning behaviors and have been found to contain human-like conceptual representations, it's unclear whether they actually functionally rely on these representations for reasoning or if they're just epiphenomena.Method: Investigated LLM internal processing during in-context concept inference using causal mediation analyses to determine functional centrality of identified conceptual subspaces, and analyzed layer-wise progression of representation construction.
Result: Found a conceptual subspace emerging in middle to late layers with persistent representational structure across contexts; demonstrated this subspace is causally central to model predictions; identified early-to-middle layers integrate contextual cues to construct the subspace, which later layers leverage for predictions.
Conclusion: LLMs dynamically construct and use structured latent representations for inference, providing insights into computational processes underlying flexible adaptation and establishing causal role of conceptual representations in LLM reasoning.
Abstract: Large language models (LLMs) exhibit emergent behaviors suggestive of human-like reasoning. While recent work has identified structured, human-like conceptual representations within these models, it remains unclear whether they functionally rely on such representations for reasoning. Here we investigate the internal processing of LLMs during in-context concept inference. Our results reveal a conceptual subspace emerging in middle to late layers, whose representational structure persists across contexts. Using causal mediation analyses, we demonstrate that this subspace is not merely an epiphenomenon but is functionally central to model predictions, establishing its causal role in inference. We further identify a layer-wise progression where attention heads in early-to-middle layers integrate contextual cues to construct and refine the subspace, which is subsequently leveraged by later layers to generate predictions. Together, these findings provide evidence that LLMs dynamically construct and use structured, latent representations in context for inference, offering insights into the computational processes underlying flexible adaptation.
[36] Thinking Makes LLM Agents Introverted: How Mandatory Thinking Can Backfire in User-Engaged Agents
Jiatong Li, Changdae Oh, Hyeong Kyu Choi, Jindong Wang, Sharon Li
Main category: cs.CL
TL;DR: Study finds that explicit thinking in user-engaged LLM agents often backfires, making agents more introverted with shorter responses and reduced information disclosure, which weakens agent-user interaction and causes performance degradation.
Details
Motivation: While reasoning/thinking techniques have improved LLM performance on complex tasks, their effectiveness in realistic user-engaged agent scenarios remains unclear. The paper investigates whether explicit thinking actually helps or harms LLM agents in interactive settings with users.Method: Comprehensive experiments across seven models, three benchmarks, and two thinking instantiations. Evaluation includes quantitative response taxonomy analysis and qualitative failure propagation case studies. Also tested explicit prompting for information disclosure.
Result: Contrary to expectations, mandatory thinking often backfires in user-engaged settings, causing performance degradation. Thinking makes agents more “introverted” - shortening responses and reducing information disclosure, which weakens agent-user information exchange and leads to downstream task failures. Explicit prompting for information disclosure reliably improves performance.
Conclusion: Information transparency awareness is crucial yet underexplored for designing reasoning agents in real-world scenarios. Proactive transparency is a vital lever for agent optimization, and thinking mechanisms need to be carefully designed to maintain effective agent-user communication.
Abstract: Eliciting reasoning has emerged as a powerful technique for improving the performance of large language models (LLMs) on complex tasks by inducing thinking. However, their effectiveness in realistic user-engaged agent scenarios remains unclear. In this paper, we conduct a comprehensive study on the effect of explicit thinking in user-engaged LLM agents. Our experiments span across seven models, three benchmarks, and two thinking instantiations, and we evaluate them through both a quantitative response taxonomy analysis and qualitative failure propagation case studies. Contrary to expectations, we find that mandatory thinking often backfires on agents in user-engaged settings, causing anomalous performance degradation across various LLMs. Our key finding reveals that thinking makes agents more ``introverted’’ by shortening responses and reducing information disclosure to users, which weakens agent-user information exchange and leads to downstream task failures. Furthermore, we demonstrate that explicitly prompting for information disclosure reliably improves performance across diverse model families, suggesting that proactive transparency is a vital lever for agent optimization. Overall, our study suggests that information transparency awareness is a crucial yet underexplored perspective for the future design of reasoning agents in real-world scenarios. Our code is available at https://github.com/deeplearning-wisc/Thinking-Agent.
[37] Pruning as a Cooperative Game: Surrogate-Assisted Layer Contribution Estimation for Large Language Models
Xuan Ding, Pengyu Tong, Ranjie Duan, Yunjian Zhang, Rui Sun, Yao Zhu
Main category: cs.CL
TL;DR: A game-theoretic framework for layer-wise pruning of LLMs using Shapley values estimated via lightweight surrogate networks and stratified Monte Carlo sampling.
Details
Motivation: LLMs have high computational demands that limit real-world deployment. Existing layer pruning methods use static heuristics and ignore layer interdependencies, reducing pruning effectiveness.Method: Formulates layer pruning as cooperative game where layers are players and model performance is utility. Uses lightweight surrogate network to estimate Shapley values (layer contributions) and stratified Monte Carlo mask sampling to reduce computation cost.
Result: Method consistently outperforms others in perplexity and zero-shot accuracy, achieving more efficient and effective layer-wise pruning for LLMs.
Conclusion: Game-theoretic approach with surrogate network estimation enables dynamic identification of critical layers while capturing inter-layer dependencies, improving LLM pruning efficiency.
Abstract: While large language models (LLMs) demonstrate impressive performance across various tasks, their deployment in real-world scenarios is still constrained by high computational demands. Layer-wise pruning, a commonly employed strategy to mitigate inference costs, can partially address this challenge. However, existing approaches generally depend on static heuristic rules and fail to account for the interdependencies among layers, thereby limiting the effectiveness of the pruning process. To this end, this paper proposes a game-theoretic framework that formulates layer pruning as a cooperative game in which each layer acts as a player and model performance serves as the utility. As computing exact Shapley values is computationally infeasible for large language models (LLMs), we propose using a lightweight surrogate network to estimate layer-wise marginal contributions. This network can predict LLM performance for arbitrary layer combinations at a low computational cost. Additionally, we employ stratified Monte Carlo mask sampling to further reduce the cost of Sharpley value estimation. This approach captures inter-layer dependencies and dynamically identifies critical layers for pruning. Extensive experiments demonstrate the consistent superiority of our method in terms of perplexity and zero-shot accuracy, achieving more efficient and effective layer-wise pruning for large language models.
[38] Systematic Failures in Collective Reasoning under Distributed Information in Multi-Agent LLMs
Yuxuan Li, Aoi Naito, Hirokazu Shirado
Main category: cs.CL
TL;DR: HiddenBench benchmark reveals multi-agent LLMs struggle with collective reasoning under distributed information, achieving only 30.1% accuracy vs 80.7% for single agents with complete information, due to failure to handle information asymmetry.
Details
Motivation: Multi-agent LLM systems are expected to improve decision-making through distributed information pooling, but systematic evaluation of this capability has been lacking. The paper aims to isolate and measure collective reasoning under distributed information separate from individual reasoning ability.Method: Introduces HiddenBench, a 65-task benchmark based on the Hidden Profile paradigm, which tests collective reasoning under distributed information. Evaluates 15 frontier LLMs, comparing multi-agent performance under distributed information vs single agents with complete information. Analyzes failure modes across prompting strategies, communication depths, and group sizes.
Result: Multi-agent LLMs achieve only 30.1% accuracy under distributed information, compared to 80.7% for single agents with complete information. The gap stems from systematic failure to recognize or act under latent information asymmetry - agents can’t reason about what others might know but haven’t expressed. Failures persist across variations and worsen with group scaling. Model scale and individual reasoning accuracy don’t reliably predict collective performance.
Conclusion: Collective information exploration in decision-making is a key limitation of multi-agent LLMs. The Hidden Profile paradigm provides a theory-grounded, reproducible framework for diagnosing collective reasoning failures in LLM-based multi-agent systems.
Abstract: Multi-agent systems built on large language models (LLMs) are expected to enhance decision-making by pooling distributed information, yet systematically evaluating this capability has remained challenging. We introduce HiddenBench, a 65-task benchmark grounded in the Hidden Profile paradigm, which isolates collective reasoning under distributed information from individual reasoning ability. Evaluating 15 frontier LLMs, we find that multi-agent LLMs achieve only 30.1% accuracy under distributed information, compared to 80.7% accuracy for single agents given complete information. We trace this gap to a systematic failure mode: agents cannot recognize or act under latent information asymmetry-they fail to reason about what others might know but have not yet expressed, leading to premature convergence on shared evidence while critical distributed facts remain unexplored. These failures persist across prompting strategies, communication depths, and group sizes-and worsen as groups scale. While some models (e.g., Gemini-2.5-Flash/Pro) outperform others, neither model scale nor individual reasoning accuracy reliably predicts collective performance. Our results identify failures in collective information exploration in decision-making as a key limitation of multi-agent LLMs, and provide a theory-grounded, reproducible framework for diagnosing collective reasoning failures.
[39] LLMs Know More About Numbers than They Can Say
Fengting Yuchi, Li Du, Jason Eisner
Main category: cs.CL
TL;DR: LLMs have internal representations of numerical magnitude that can be probed via linear projections, but these representations don’t translate to accurate explicit numerical comparisons, suggesting a disconnect between internal knowledge and verbal reasoning.
Details
Motivation: Despite LLMs' ability to solve math problems, they struggle with numerical comparisons involving mixed notation (scientific vs. decimal), raising questions about whether they truly understand numerical magnitude.Method: Probe hidden states of open-source LLMs using linear projections to extract log-magnitudes of numbers, train linear classifiers to rank numeral pairs, and use probe log-loss as auxiliary objective during fine-tuning.
Result: Linear projections recover numbers with 2.3% error on synthetic text and 19.06% on scientific papers; ranking classifiers achieve >90% accuracy, but explicit verbal comparisons only reach 50-70% accuracy; fine-tuning with probe objective improves verbal accuracy by 3.22%.
Conclusion: LLMs encode numerical magnitude internally but fail to use this knowledge effectively in explicit reasoning; improving internal representations can enhance numerical reasoning capabilities.
Abstract: Although state-of-the-art LLMs can solve math problems, we find that they make errors on numerical comparisons with mixed notation: “Which is larger, $5.7 \times 10^2$ or $580$?” This raises a fundamental question: Do LLMs even know how big these numbers are? We probe the hidden states of several smaller open-source LLMs. A single linear projection of an appropriate hidden layer encodes the log-magnitudes of both kinds of numerals, allowing us to recover the numbers with relative error of about 2.3% (on restricted synthetic text) or 19.06% (on scientific papers). Furthermore, the hidden state after reading a pair of numerals encodes their ranking, with a linear classifier achieving over 90% accuracy. Yet surprisingly, when explicitly asked to rank the same pairs of numerals, these LLMs achieve only 50-70% accuracy, with worse performance for models whose probes are less effective. Finally, we show that incorporating the classifier probe’s log-loss as an auxiliary objective during finetuning brings an additional 3.22% improvement in verbalized accuracy over base models, demonstrating that improving models’ internal magnitude representations can enhance their numerical reasoning capabilities.
[40] StoryBox: Collaborative Multi-Agent Simulation for Hybrid Bottom-Up Long-Form Story Generation Using Large Language Models
Zehao Chen, Rong Pan, Haoran Li
Main category: cs.CL
TL;DR: Multi-agent simulation approach for long-form story generation where agents interact in dynamic environments to create emergent events that form organic stories exceeding 10,000 words.
Details
Motivation: Inspired by how human writers begin with mental scenes of character interactions, the paper addresses limitations of traditional top-down story generation approaches that impose rigid structures, aiming to create more spontaneous and engaging storytelling through organic character development.Method: Proposes hybrid bottom-up long-form story generation using multi-agent simulations. Agents interact within dynamic sandbox environments where their behaviors and interactions generate emergent events that form the story foundation, enabling natural plot progression.
Result: Achieves state-of-the-art performance across several metrics, capable of generating coherent and consistent stories exceeding 10,000 words, addressing key challenges faced by current story generation models.
Conclusion: The hybrid bottom-up approach offers a scalable and innovative solution for creating dynamic, immersive long-form stories that evolve organically from agent-driven interactions, enabling more natural storytelling.
Abstract: Human writers often begin their stories with an overarching mental scene, where they envision the interactions between characters and their environment. Inspired by this creative process, we propose a novel approach to long-form story generation, termed hybrid bottom-up long-form story generation, using multi-agent simulations. In our method, agents interact within a dynamic sandbox environment, where their behaviors and interactions with one another and the environment generate emergent events. These events form the foundation for the story, enabling organic character development and plot progression. Unlike traditional top-down approaches that impose rigid structures, our hybrid bottom-up approach allows for the natural unfolding of events, fostering more spontaneous and engaging storytelling. The system is capable of generating stories exceeding 10,000 words while maintaining coherence and consistency, addressing some of the key challenges faced by current story generation models. We achieve state-of-the-art performance across several metrics. This approach offers a scalable and innovative solution for creating dynamic, immersive long-form stories that evolve organically from agent-driven interactions.
[41] TodoEvolve: Learning to Architect Agent Planning Systems
Jiaxi Liu, Yanzuo Jiang, Guibin Zhang, Zihan Zhang, Heng Chang, Zhenfei Yin, Qibing Ren, Junchi Yan
Main category: cs.CL
TL;DR: TodoEvolve is a meta-planning paradigm that autonomously synthesizes and dynamically revises task-specific planning architectures for agent systems, outperforming hand-crafted approaches while maintaining efficiency.
Details
Motivation: Existing agent planning approaches rely on fixed, hand-crafted planning structures that lack flexibility to adapt to the structural diversity of open-ended problems in complex, long-horizon tasks.Method: 1) Construct PlanFactory - a modular design space standardizing diverse planning paradigms within a unified codebase; 2) Collect planning trajectories; 3) Train Todo-14B model using Impedance-Guided Preference Optimization (IGPO), a multi-objective RL objective encouraging performant, stable, and token-efficient planning systems.
Result: Empirical evaluations on five agentic benchmarks demonstrate that TodoEvolve consistently surpasses carefully engineered planning modules while maintaining economical API costs and runtime overhead.
Conclusion: TodoEvolve provides a flexible meta-planning paradigm that autonomously synthesizes adaptive planning architectures, addressing limitations of fixed planning structures in agent systems.
Abstract: Planning has become a central capability for contemporary agent systems in navigating complex, long-horizon tasks, yet existing approaches predominantly rely on fixed, hand-crafted planning structures that lack the flexibility to adapt to the structural diversity of open-ended problems. To address this limitation, we introduce TodoEvolve, a meta-planning paradigm that autonomously synthesizes and dynamically revises task-specific planning architectures. Specifically, we first construct PlanFactory, a modular design space that standardizes diverse planning paradigms within a unified codebase encompassing topology, initialization, adaptation, and navigation, thereby providing a common interface for heterogeneous planning patterns. Leveraging PlanFactory, we collect high-quality planning trajectories and train Todo-14B via \textit{Impedance-Guided Preference Optimization} (IGPO), a multi-objective reinforcement learning objective that encourages the generation of planning systems that are performant, stable, and token-efficient across arbitrary tasks and agent backbones. Empirical evaluations on five agentic benchmarks demonstrate that TodoEvolve consistently surpasses carefully engineered planning modules while maintaining economical API costs and runtime overhead.
[42] Evaluating and Calibrating LLM Confidence on Questions with Multiple Correct Answers
Yuhan Wang, Shiyu Ni, Zhikai Ding, Zihang Zhan, Yuanzi Li, Keping Bi
Main category: cs.CL
TL;DR: The paper introduces MACE benchmark for studying confidence calibration in LLMs when multiple valid answers exist, and proposes Semantic Confidence Aggregation (SCA) method to address systematic underestimation of confidence in such scenarios.
Details
Motivation: Existing confidence calibration methods for LLMs fail when multiple valid answers exist, as disagreement among equally correct responses leads to systematic underestimation of confidence. Current training-free calibration methods have only been studied under single-answer QA settings.Method: 1) Introduces MACE benchmark with 12,000 factual questions across six domains with varying numbers of correct answers. 2) Evaluates 15 calibration methods across 4 LLM families (7B-72B). 3) Proposes Semantic Confidence Aggregation (SCA) which aggregates confidence over multiple high-probability sampled responses to address the miscalibration issue.
Result: Experiments show that while accuracy increases with answer cardinality, estimated confidence consistently decreases, causing severe miscalibration for questions with mixed answer counts. SCA achieves state-of-the-art calibration performance under mixed-answer settings while maintaining strong calibration on single-answer questions.
Conclusion: The paper identifies a critical limitation in current LLM confidence calibration methods when multiple valid answers exist, introduces a comprehensive benchmark for studying this phenomenon, and proposes an effective solution (SCA) that significantly improves calibration performance in such scenarios.
Abstract: Confidence calibration is essential for making large language models (LLMs) reliable, yet existing training-free methods have been primarily studied under single-answer question answering. In this paper, we show that these methods break down in the presence of multiple valid answers, where disagreement among equally correct responses leads to systematic underestimation of confidence. To enable a systematic study of this phenomenon, we introduce MACE, a benchmark of 12,000 factual questions spanning six domains with varying numbers of correct answers. Experiments across 15 representative calibration methods and four LLM families (7B-72B) reveal that while accuracy increases with answer cardinality, estimated confidence consistently decreases, causing severe miscalibration for questions with mixed answer counts. To address this issue, we propose Semantic Confidence Aggregation (SCA), which aggregates confidence over multiple high-probability sampled responses. SCA achieves state-of-the-art calibration performance under mixed-answer settings while preserving strong calibration on single-answer questions.
[43] SparseEval: Efficient Evaluation of Large Language Models by Sparse Optimization
Taolin Zhang, Hang Guo, Wang Lu, Tao Dai, Shu-Tao Xia, Jindong Wang
Main category: cs.CL
TL;DR: SparseEval: A method for efficient benchmarking of large language models using sparse optimization and gradient descent to select representative anchor items, reducing computational costs while maintaining evaluation accuracy.
Details
Motivation: Evaluating large language models has become computationally expensive due to the high cost of inference on many benchmark samples. The paper aims to address this by leveraging the sparsity in model-item performance matrices to enable efficient benchmarking.Method: Formulates efficient benchmarking as a sparse optimization problem. Uses gradient descent to optimize anchor weights and employs iterative refinement for anchor selection. Utilizes MLP representation capacity for sparse optimization and proposes Anchor Importance Score and Candidate Importance Score for task-aware refinement.
Result: Extensive experiments show low estimation error and high Kendall’s τ across various benchmarks, demonstrating superior robustness and practicality in real-world scenarios.
Conclusion: SparseEval provides an effective approach for efficient benchmarking of LLMs by selecting representative anchor items through sparse optimization, significantly reducing computational costs while maintaining evaluation accuracy.
Abstract: As large language models (LLMs) continue to scale up, their performance on various downstream tasks has significantly improved. However, evaluating their capabilities has become increasingly expensive, as performing inference on a large number of benchmark samples incurs high computational costs. In this paper, we revisit the model-item performance matrix and show that it exhibits sparsity, that representative items can be selected as anchors, and that the task of efficient benchmarking can be formulated as a sparse optimization problem. Based on these insights, we propose SparseEval, a method that, for the first time, adopts gradient descent to optimize anchor weights and employs an iterative refinement strategy for anchor selection. We utilize the representation capacity of MLP to handle sparse optimization and propose the Anchor Importance Score and Candidate Importance Score to evaluate the value of each item for task-aware refinement. Extensive experiments demonstrate the low estimation error and high Kendall’s~$τ$ of our method across a variety of benchmarks, showcasing its superior robustness and practicality in real-world scenarios. Code is available at {https://github.com/taolinzhang/SparseEval}.
[44] Patches of Nonlinearity: Instruction Vectors in Large Language Models
Irina Bigoulaeva, Jonas Rohweder, Subhabrata Dutta, Iryna Gurevych
Main category: cs.CL
TL;DR: The paper investigates how instruction-tuned language models internally process instructions through mechanistic analysis, identifying localized “Instruction Vectors” that act as circuit selectors in later layers.
Details
Motivation: Despite the widespread use of instruction-tuned language models, little is known about how they internally process instructions. The authors aim to address this gap from a mechanistic interpretability perspective, specifically examining how instruction-specific representations are constructed and utilized during supervised fine-tuning and direct preference optimization.Method: The authors use causal mediation analysis to investigate instruction representation localization. They identify “Instruction Vectors” (IVs) and propose a novel method to localize information processing in language models that avoids the implicit linear assumptions of patching-based techniques. They analyze how task representations formed in early layers select different information pathways in later layers.
Result: The study finds that instruction representation is fairly localized in models, with Instruction Vectors demonstrating both linear separability and non-linear causal interaction. These IVs act as circuit selectors - conditioned on task representations formed in early layers, different information pathways are selected in later layers to solve specific tasks.
Conclusion: The research challenges the linear representation hypothesis common in mechanistic interpretability by showing that instruction processing involves both linear separability and non-linear causal interactions. The findings provide insights into how instruction-tuned models internally process and route information based on task representations.
Abstract: Despite the recent success of instruction-tuned language models and their ubiquitous usage, very little is known of how models process instructions internally. In this work, we address this gap from a mechanistic point of view by investigating how instruction-specific representations are constructed and utilized in different stages of post-training: Supervised Fine-Tuning (SFT) and Direct Preference Optimization (DPO). Via causal mediation, we identify that instruction representation is fairly localized in models. These representations, which we call Instruction Vectors (IVs), demonstrate a curious juxtaposition of linear separability along with non-linear causal interaction, broadly questioning the scope of the linear representation hypothesis commonplace in mechanistic interpretability. To disentangle the non-linear causal interaction, we propose a novel method to localize information processing in language models that is free from the implicit linear assumptions of patching-based techniques. We find that, conditioned on the task representations formed in the early layers, different information pathways are selected in the later layers to solve that task, i.e., IVs act as circuit selectors.
[45] Bielik Guard: Efficient Polish Language Safety Classifiers for LLM Content Moderation
Krzysztof Wróbel, Jan Maria Kowalski, Jerzy Surma, Igor Ciuciura, Maciej Szymański
Main category: cs.CL
TL;DR: Bielik Guard is a family of compact Polish language safety classifiers for LLM applications, with two variants (0.1B and 0.5B parameters) that classify content across five safety categories.
Details
Motivation: As LLMs become increasingly deployed in Polish language applications, there's a need for efficient and accurate content safety classifiers to ensure appropriate content moderation.Method: Developed two model variants based on Polish language models (MMLW-RoBERTa-base and PKOBP/polish-roberta-8k), fine-tuned on a community-annotated dataset of 6,885 Polish texts across five safety categories.
Result: Both models achieve strong performance, with the 0.5B variant showing best overall discrimination (F1: 0.791 micro, 0.785 macro) and the 0.1B variant demonstrating exceptional efficiency and superior precision (77.65%) with low false positive rate (0.63%) on real user prompts.
Conclusion: Bielik Guard provides effective Polish language safety classification for LLM applications, with models designed to provide appropriate responses rather than simple content blocking, particularly for sensitive categories like self-harm.
Abstract: As Large Language Models (LLMs) become increasingly deployed in Polish language applications, the need for efficient and accurate content safety classifiers has become paramount. We present Bielik Guard, a family of compact Polish language safety classifiers comprising two model variants: a 0.1B parameter model based on MMLW-RoBERTa-base and a 0.5B parameter model based on PKOBP/polish-roberta-8k. Fine-tuned on a community-annotated dataset of 6,885 Polish texts, these models classify content across five safety categories: Hate/Aggression, Vulgarities, Sexual Content, Crime, and Self-Harm. Our evaluation demonstrates that both models achieve strong performance on multiple benchmarks. The 0.5B variant offers the best overall discrimination capability with F1 scores of 0.791 (micro) and 0.785 (macro) on the test set, while the 0.1B variant demonstrates exceptional efficiency. Notably, Bielik Guard 0.1B v1.1 achieves superior precision (77.65%) and very low false positive rate (0.63%) on real user prompts, outperforming HerBERT-PL-Guard (31.55% precision, 4.70% FPR) despite identical model size. The models are publicly available and designed to provide appropriate responses rather than simple content blocking, particularly for sensitive categories like self-harm.
[46] Lost in Translation? A Comparative Study on the Cross-Lingual Transfer of Composite Harms
Vaibhav Shukla, Hardik Sharma, Adith N Reganti, Soham Wasmatkar, Bagesh Kumar, Vrijendra Singh
Main category: cs.CL
TL;DR: A study on multilingual safety evaluation of LLMs using translation-based benchmarks, showing that safety alignment degrades in Indic languages, especially under adversarial syntax.
Details
Motivation: Most LLM safety evaluations focus on English, and translation-based approaches don't capture how harmful intent or structure changes across languages. The paper aims to study how safety alignment holds up as both syntax and semantics shift across different languages.Method: Introduces CompositeHarm benchmark combining two English datasets (AttaQ for structured adversarial attacks and MMSafetyBench for contextual real-world harms) and extends them into six languages (English, Hindi, Assamese, Marathi, Kannada, Gujarati). Uses three large models with lightweight inference strategies inspired by edge-AI design principles for computational efficiency.
Result: Attack success rates rise sharply in Indic languages, especially under adversarial syntax, while contextual harms transfer more moderately. The lightweight inference strategies enable large-scale multilingual safety testing while being computationally feasible and environmentally conscious.
Conclusion: Translated benchmarks are a necessary first step but not sufficient for building grounded, resource-aware, language-adaptive safety systems. Multilingual safety evaluation requires approaches that account for language-specific variations in harmful content.
Abstract: Most safety evaluations of large language models (LLMs) remain anchored in English. Translation is often used as a shortcut to probe multilingual behavior, but it rarely captures the full picture, especially when harmful intent or structure morphs across languages. Some types of harm survive translation almost intact, while others distort or disappear. To study this effect, we introduce CompositeHarm, a translation-based benchmark designed to examine how safety alignment holds up as both syntax and semantics shift. It combines two complementary English datasets, AttaQ, which targets structured adversarial attacks, and MMSafetyBench, which covers contextual, real-world harms, and extends them into six languages: English, Hindi, Assamese, Marathi, Kannada, and Gujarati. Using three large models, we find that attack success rates rise sharply in Indic languages, especially under adversarial syntax, while contextual harms transfer more moderately. To ensure scalability and energy efficiency, our study adopts lightweight inference strategies inspired by edge-AI design principles, reducing redundant evaluation passes while preserving cross-lingual fidelity. This design makes large-scale multilingual safety testing both computationally feasible and environmentally conscious. Overall, our results show that translated benchmarks are a necessary first step, but not a sufficient one, toward building grounded, resource-aware, language-adaptive safety systems.
[47] Cross-Linguistic Persona-Driven Data Synthesis for Robust Multimodal Cognitive Decline Detection
Rui Feng, Zhiyao Luo, Liuyu Wu, Wei Wang, Yuting Song, Yong Liu, Kok Pin Ng, Jianqing Li, Xingyao Wang
Main category: cs.CL
TL;DR: SynCog: A framework using controllable zero-shot multimodal data synthesis and Chain-of-Thought fine-tuning to improve MCI diagnosis from speech, addressing data scarcity and interpretability issues while enabling cross-lingual generalization.
Details
Motivation: Speech-based digital biomarkers for MCI diagnosis face clinical data scarcity, lack of interpretable reasoning, and poor cross-lingual generalization. Current models struggle with transparency and fail to provide clinical trust.Method: SynCog integrates controllable zero-shot multimodal data synthesis to simulate diverse virtual subjects with varying cognitive profiles, and Chain-of-Thought deduction fine-tuning to enable explicit diagnostic reasoning. It generates synthetic clinical data across languages and fine-tunes multimodal LLMs with CoT strategies.
Result: Achieved Macro-F1 scores of 80.67% on ADReSS and 78.46% on ADReSSo benchmarks, outperforming baselines. Demonstrated cross-linguistic generalization with 48.71% Macro-F1 on independent Mandarin cohort (CIR-E).
Conclusion: SynCog addresses key barriers in speech-based MCI diagnosis by alleviating data scarcity, providing interpretable reasoning, and enabling cross-lingual generalization, representing progress toward clinically trustworthy global cognitive assessment tools.
Abstract: Speech-based digital biomarkers represent a scalable, non-invasive frontier for the early identification of Mild Cognitive Impairment (MCI). However, the development of robust diagnostic models remains impeded by acute clinical data scarcity and a lack of interpretable reasoning. Current solutions frequently struggle with cross-lingual generalization and fail to provide the transparent rationales essential for clinical trust. To address these barriers, we introduce SynCog, a novel framework integrating controllable zero-shot multimodal data synthesis with Chain-of-Thought (CoT) deduction fine-tuning. Specifically, SynCog simulates diverse virtual subjects with varying cognitive profiles to effectively alleviate clinical data scarcity. This generative paradigm enables the rapid, zero-shot expansion of clinical corpora across diverse languages, effectively bypassing data bottlenecks in low-resource settings and bolstering the diagnostic performance of Multimodal Large Language Models (MLLMs). Leveraging this synthesized dataset, we fine-tune a foundational multimodal backbone using a CoT deduction strategy, empowering the model to explicitly articulate diagnostic thought processes rather than relying on black-box predictions. Extensive experiments on the ADReSS and ADReSSo benchmarks demonstrate that augmenting limited clinical data with synthetic phenotypes yields competitive diagnostic performance, achieving Macro-F1 scores of 80.67% and 78.46%, respectively, outperforming current baseline models. Furthermore, evaluation on an independent real-world Mandarin cohort (CIR-E) demonstrates robust cross-linguistic generalization, attaining a Macro-F1 of 48.71%. These findings constitute a critical step toward providing clinically trustworthy and linguistically inclusive cognitive assessment tools for global healthcare.
[48] The Judge Who Never Admits: Hidden Shortcuts in LLM-based Evaluation
Arash Marioriyad, Omid Ghahroodi, Ehsaneddin Asgari, Mohammad Hossein Rohban, Mahdieh Soleymani Baghshah
Main category: cs.CL
TL;DR: LLMs used as automatic judges show significant sensitivity to irrelevant contextual cues (source, temporal, demographic) but rarely acknowledge these biases in their rationales, creating an explanation gap in model-based evaluation.
Details
Motivation: To investigate whether LLM judges are faithful evaluators that base verdicts solely on content quality and transparently reflect decision factors, rather than being influenced by irrelevant contextual cues.Method: Controlled cue perturbations with synthetic metadata labels injected into evaluation prompts for six judge models (GPT-4o, Gemini-2.0-Flash, etc.) across two datasets: ELI5 (factual QA) and LitBench (creative writing). Studied six cue families: source, temporal, age, gender, ethnicity, and educational status. Measured verdict shift rates (VSR) and introduced cue acknowledgment rate (CAR) to quantify explicit cue references in rationales.
Result: LLM judges show substantial sensitivity to irrelevant cues (provenance hierarchies, recency preferences, educational-status favoritism) but CAR is typically near zero, indicating shortcut reliance is largely unreported. CAR is dataset-dependent - more likely in factual ELI5 but collapses in open-ended LitBench, where large verdict shifts persist despite zero acknowledgment.
Conclusion: The combination of substantial verdict sensitivity and limited cue acknowledgment reveals an explanation gap in LLM-as-judge pipelines, raising reliability concerns for model-based evaluation in research and deployment.
Abstract: Large language models (LLMs) are increasingly used as automatic judges to evaluate system outputs in tasks such as reasoning, question answering, and creative writing. A faithful judge should base its verdicts solely on content quality, remain invariant to irrelevant context, and transparently reflect the factors driving its decisions. We test this ideal via controlled cue perturbations-synthetic metadata labels injected into evaluation prompts-for six judge models: GPT-4o, Gemini-2.0-Flash, Gemma-3-27B, Qwen3-235B, Claude-3-Haiku, and Llama3-70B. Experiments span two complementary datasets with distinct evaluation regimes: ELI5 (factual QA) and LitBench (open-ended creative writing). We study six cue families: source, temporal, age, gender, ethnicity, and educational status. Beyond measuring verdict shift rates (VSR), we introduce cue acknowledgment rate (CAR) to quantify whether judges explicitly reference the injected cues in their natural-language rationales. Across cues with strong behavioral effects-e.g., provenance hierarchies (Expert > Human > LLM > Unknown), recency preferences (New > Old), and educational-status favoritism-CAR is typically at or near zero, indicating that shortcut reliance is largely unreported even when it drives decisions. Crucially, CAR is also dataset-dependent: explicit cue recognition is more likely to surface in the factual ELI5 setting for some models and cues, but often collapses in the open-ended LitBench regime, where large verdict shifts can persist despite zero acknowledgment. The combination of substantial verdict sensitivity and limited cue acknowledgment reveals an explanation gap in LLM-as-judge pipelines, raising concerns about reliability of model-based evaluation in both research and deployment.
[49] DeltaKV: Residual-Based KV Cache Compression via Long-Range Similarity
Jitai Hao, Qiang Huang, Yaowei Wang, Min Zhang, Jun Yu
Main category: cs.CL
TL;DR: DeltaKV is a residual-based KV cache compression framework that reduces memory usage by encoding semantic residuals relative to historical references, combined with Sparse-vLLM inference engine for hardware efficiency.
Details
Motivation: Efficient long-context LLM deployment is bottlenecked by linear growth of KV cache memory. Existing compression methods struggle to balance accuracy, compression ratio, and hardware efficiency.Method: DeltaKV encodes semantic residuals relative to retrieved historical references instead of discarding tokens, preserving fidelity while reducing storage. Sparse-vLLM provides decoupled memory management and kernels optimized for sparse KV layouts.
Result: DeltaKV reduces KV cache memory to 29% of original while maintaining near-lossless accuracy on LongBench, SCBench, and AIME. With Sparse-vLLM, achieves up to 2× throughput improvement over vLLM in long-context scenarios.
Conclusion: The approach demonstrates a practical path toward scalable long-context LLM deployment by balancing compression efficiency with hardware acceleration.
Abstract: The deployment of efficient long-context LLMs in applications like autonomous agents, long-chain reasoning, and creative writing is fundamentally bottlenecked by the linear growth of KV cache memory. Existing compression and eviction methods often struggle to balance accuracy, compression ratio, and hardware efficiency. We propose DeltaKV, a residual-based KV cache compression framework motivated by two empirical findings: long-range inter-token similarity and highly shared latent components in KV representations. Instead of discarding tokens, DeltaKV encodes semantic residuals relative to retrieved historical references, preserving fidelity while substantially reducing storage. To translate compression gains into real system speedups, we further introduce Sparse-vLLM, a high-performance inference engine with decoupled memory management and kernels optimized for sparse and irregular KV layouts. Experiments show that DeltaKV reduces KV cache memory to 29% of the original while maintaining near-lossless accuracy on LongBench, SCBench, and AIME. When integrated with Sparse-vLLM, it achieves up to 2$\times$ throughput improvement over vLLM in long-context scenarios, demonstrating a practical path toward scalable long-context LLM deployment. Code, model checkpoints, and datasets are available at https://github.com/CURRENTF/Sparse-vLLM.
[50] Diverge to Induce Prompting: Multi-Rationale Induction for Zero-Shot Reasoning
Po-Chun Chen, Hen-Hsen Huang, Hsin-Hsi Chen
Main category: cs.CL
TL;DR: DIP is a prompting framework that generates multiple diverse reasoning strategies for each question, elaborates them into detailed plans, then induces a final plan, improving zero-shot reasoning accuracy without heavy sampling.
Details
Motivation: Standard Chain-of-Thought prompting suffers from instability in reasoning paths, and existing methods that use single reasoning strategies limit performance across diverse tasks. There's a need for more robust prompting that leverages multiple reasoning approaches.Method: Diverge-to-Induce Prompting (DIP) framework: 1) Generate multiple diverse high-level rationales for each question, 2) Elaborate each rationale into detailed step-by-step draft plans, 3) Induce these draft plans into a final comprehensive plan.
Result: DIP outperforms single-strategy prompting methods, demonstrating improved zero-shot reasoning accuracy without relying on resource-intensive sampling techniques.
Conclusion: Multi-plan induction through diverse reasoning strategies enhances prompt-based reasoning, providing a more robust approach than single-strategy methods for diverse tasks.
Abstract: To address the instability of unguided reasoning paths in standard Chain-of-Thought prompting, recent methods guide large language models (LLMs) by first eliciting a single reasoning strategy. However, relying on just one strategy for each question can still limit performance across diverse tasks. We propose Diverge-to-Induce Prompting (DIP), a framework that first prompts an LLM to generate multiple diverse high-level rationales for each question. Each rationale is then elaborated into a detailed, step-by-step draft plan. Finally, these draft plans are induced into a final plan. DIP enhances zero-shot reasoning accuracy without reliance on resource-intensive sampling. Experiments show that DIP outperforms single-strategy prompting, demonstrating the effectiveness of multi-plan induction for prompt-based reasoning.
[51] Beyond Raw Detection Scores: Markov-Informed Calibration for Boosting Machine-Generated Text Detection
Chenwang Wu, Yiu-ming Cheung, Shuhai Zhang, Bo Han, Defu Lian
Main category: cs.CL
TL;DR: Proposes Markov random field calibration to improve machine-generated text detection by addressing score bias from generation randomness
Details
Motivation: Machine-generated texts pose risks like disinformation and phishing, requiring reliable detection. Metric-based methods are practical but suffer from biased token-level detection scores due to randomness in generation processes.Method: 1) Analyzes metric-based methods within unified framework, identifying core challenge of biased token-level scores. 2) Reveals two relationships for calibration: Neighbor Similarity and Initial Instability. 3) Proposes Markov-informed score calibration using Markov random fields with mean-field approximation as lightweight component.
Result: Extensive experiments show significant gains over baselines in cross-LLM and paraphrasing attack scenarios with negligible computational overhead.
Conclusion: The proposed Markov random field calibration effectively addresses score bias in machine-generated text detection and can be seamlessly integrated into existing detectors.
Abstract: While machine-generated texts (MGTs) offer great convenience, they also pose risks such as disinformation and phishing, highlighting the need for reliable detection. Metric-based methods, which extract statistically distinguishable features of MGTs, are often more practical than complex model-based methods that are prone to overfitting. Given their diverse designs, we first place representative metric-based methods within a unified framework, enabling a clear assessment of their advantages and limitations. Our analysis identifies a core challenge across these methods: the token-level detection score is easily biased by the inherent randomness of the MGTs generation process. To address this, we theoretically and empirically reveal two relationships of context detection scores that may aid calibration: Neighbor Similarity and Initial Instability. We then propose a Markov-informed score calibration strategy that models these relationships using Markov random fields, and implements it as a lightweight component via a mean-field approximation, allowing our method to be seamlessly integrated into existing detectors. Extensive experiments in various real-world scenarios, such as cross-LLM and paraphrasing attacks, demonstrate significant gains over baselines with negligible computational overhead. The code is available at https://github.com/tmlr-group/MRF_Calibration.
[52] TDGNet: Hallucination Detection in Diffusion Language Models via Temporal Dynamic Graphs
Arshia Hemmat, Philip Torr, Yongqiang Chen, Junchi Yu
Main category: cs.CL
TL;DR: TDGNet is a temporal dynamic graph framework for hallucination detection in diffusion language models that analyzes evolving attention graphs across the denoising trajectory.
Details
Motivation: Hallucination detection for diffusion language models (D-LLMs) is underexplored, and existing detectors for auto-regressive LLMs don't transfer well because they rely on single-pass cues while D-LLMs have factuality evidence distributed across the entire denoising trajectory that may appear, drift, or self-correct over time.Method: TDGNet formulates hallucination detection as learning over evolving token-level attention graphs. At each denoising step, it sparsifies the attention graph, updates per-token memories via message passing, and applies temporal attention to aggregate trajectory-wide evidence for final prediction.
Result: Experiments on LLaDA-8B and Dream-7B across QA benchmarks show consistent AUROC improvements over output-based, latent-based, and static-graph baselines, with single-pass inference and modest overhead.
Conclusion: Temporal reasoning on attention graphs is crucial for robust hallucination detection in diffusion language models, as demonstrated by TDGNet’s superior performance.
Abstract: Diffusion language models (D-LLMs) offer parallel denoising and bidirectional context, but hallucination detection for D-LLMs remains underexplored. Prior detectors developed for auto-regressive LLMs typically rely on single-pass cues and do not directly transfer to diffusion generation, where factuality evidence is distributed across the denoising trajectory and may appear, drift, or be self-corrected over time. We introduce TDGNet, a temporal dynamic graph framework that formulates hallucination detection as learning over evolving token-level attention graphs. At each denoising step, we sparsify the attention graph and update per-token memories via message passing, then apply temporal attention to aggregate trajectory-wide evidence for final prediction. Experiments on LLaDA-8B and Dream-7B across QA benchmarks show consistent AUROC improvements over output-based, latent-based, and static-graph baselines, with single-pass inference and modest overhead. These results highlight the importance of temporal reasoning on attention graphs for robust hallucination detection in diffusion language models.
[53] Emergent Search and Backtracking in Latent Reasoning Models
Jasmine Cui, Charles Ye
Main category: cs.CL
TL;DR: Latent reasoning transformers perform deliberation entirely in continuous hidden space instead of verbalizing intermediate steps, learning a structured search process with exploration, tentative commitment, and backtracking phases.
Details
Motivation: To understand how language models reason without verbalizing intermediate steps, investigating what happens when models think without words in continuous hidden space rather than through chain-of-thought verbalization.Method: Analyze latent reasoning transformers (LRTs) that perform deliberation entirely in continuous hidden space, decoding the model’s evolving beliefs at every step on multiple-choice QA benchmarks to understand the structured search process.
Result: LRTs learn a structured search process with consistent trajectory: exploration phase spreading probability mass, tentative commitment to frontrunner, and convergence or backtracking. Backtracking is prevalent (32%), beneficial (34% accuracy gain), and directed away from semantically closest distractors toward correct answers. Search is adaptive - replacing distractors with implausible alternatives shortens exploration by 54%.
Conclusion: Latent reasoning models achieve in activation space what chain-of-thought achieves through words: the ability to be wrong, notice, and recover, demonstrating that structured reasoning can occur entirely in continuous hidden representations without verbalization.
Abstract: What happens when a language model thinks without words? Standard reasoning LLMs verbalize intermediate steps as chain-of-thought; latent reasoning transformers (LRTs) instead perform deliberation entirely in continuous hidden space. We investigate an LRT, decoding the model’s evolving beliefs at every step on a multiple-choice QA benchmark. We find that the model spontaneously learns a structured search process in latent space. Deliberation follows a consistent trajectory: an exploration phase where probability mass spreads across candidates, tentative commitment to a frontrunner, and either convergence or backtracking. Backtracking is prevalent (32% of instances), beneficial (34% accuracy gain over non-backtracking instances), and predominantly directed away from the semantically closest distractor toward the correct answer. The search is adaptive: replacing distractors with implausible alternatives shortens exploration by 54%. Latent reasoning models achieve in activation space what chain-of-thought achieves through words: the ability to be wrong, notice, and recover.
[54] Gender and Race Bias in Consumer Product Recommendations by Large Language Models
Ke Xu, Shera Potka, Alex Thomo
Main category: cs.CL
TL;DR: LLMs show gender and race biases in product recommendations, quantified through prompt engineering and multiple analytical methods revealing significant disparities across demographic groups.
Details
Motivation: Large Language Models are increasingly used for consumer product recommendations, but their potential for embedding and amplifying gender and race biases remains underexplored, creating a need to examine these biases systematically.Method: Used prompt engineering to elicit product suggestions from LLMs for various race and gender groups, then employed three analytical methods: Marked Words, Support Vector Machines, and Jensen-Shannon Divergence to identify and quantify biases.
Result: Findings reveal significant disparities in recommendations for different demographic groups, demonstrating that LLMs exhibit systematic biases in their product suggestions.
Conclusion: There is a clear need for more equitable LLM recommendation systems to address the identified gender and race biases in product recommendations.
Abstract: Large Language Models are increasingly employed in generating consumer product recommendations, yet their potential for embedding and amplifying gender and race biases remains underexplored. This paper serves as one of the first attempts to examine these biases within LLM-generated recommendations. We leverage prompt engineering to elicit product suggestions from LLMs for various race and gender groups and employ three analytical methods-Marked Words, Support Vector Machines, and Jensen-Shannon Divergence-to identify and quantify biases. Our findings reveal significant disparities in the recommendations for demographic groups, underscoring the need for more equitable LLM recommendation systems.
[55] DIAL-SUMMER: A Structured Evaluation Framework of Hierarchical Errors in Dialogue Summaries
Sahana Ramnath, Nima Chitsazan, Mingyang Zhou, Chia-Hsuan Lee, Shi-Xiong Zhang, Stephen Rawls, Sambit Sahu, Sangwoo Cho, Xiang Ren, Genta Indra Winata, Akshaj Kumar Veldanda
Main category: cs.CL
TL;DR: DIAL-SUMMER is a framework for evaluating dialogue summaries with a hierarchical taxonomy addressing structural and viewpoint shifts between dialogues and their summaries.
Details
Motivation: Existing dialogue summary evaluation methods ignore two key complexities: structural shift from scattered multi-speaker dialogue to organized summary sentences, and viewpoint shift from first/second-person dialogue to third-person summary narration.Method: Proposes DIAL-SUMMER framework with hierarchical error taxonomy at dialogue-level (speakers/turns) and within-turn-level (information inside turns), plus a manually annotated dataset of dialogue summaries with fine-grained errors.
Result: Empirical analysis reveals trends like middle dialogue turns being most frequently missed and extrinsic hallucinations occurring mostly at summary ends. LLM-Judges struggle with error detection, showing dataset’s challenging nature.
Conclusion: DIAL-SUMMER provides robust taxonomy and challenging dataset for dialogue summary evaluation, highlighting need for future work to improve LLMs’ performance on this task.
Abstract: Dialogues are a predominant mode of communication for humans, and it is immensely helpful to have automatically generated summaries of them (e.g., to revise key points discussed in a meeting, to review conversations between customer agents and product users). Prior works on dialogue summary evaluation largely ignore the complexities specific to this task: (i) shift in structure, from multiple speakers discussing information in a scattered fashion across several turns, to a summary’s sentences, and (ii) shift in narration viewpoint, from speakers’ first/second-person narration, standardized third-person narration in the summary. In this work, we introduce our framework DIALSUMMER to address the above. We propose DIAL-SUMMER’s taxonomy of errors to comprehensively evaluate dialogue summaries at two hierarchical levels: DIALOGUE-LEVEL that focuses on the broader speakers/turns, and WITHIN-TURN-LEVEL that focuses on the information talked about inside a turn. We then present DIAL-SUMMER’s dataset composed of dialogue summaries manually annotated with our taxonomy’s fine-grained errors. We conduct empirical analyses of these annotated errors, and observe interesting trends (e.g., turns occurring in middle of the dialogue are the most frequently missed in the summary, extrinsic hallucinations largely occur at the end of the summary). We also conduct experiments on LLM-Judges’ capability at detecting these errors, through which we demonstrate the challenging nature of our dataset, the robustness of our taxonomy, and the need for future work in this field to enhance LLMs’ performance in the same. Code and inference dataset coming soon.
[56] NLP for Local Governance Meeting Records: A Focus Article on Tasks, Datasets, Metrics and Benchmark
Ricardo Campos, José Pedro Evans, José Miguel Isidro, Miguel Marques, Luís Filipe Cunha, Alípio Jorge, Sérgio Nunes, Nuno Guimarães
Main category: cs.CL
TL;DR: A review article examining how NLP methods (document segmentation, entity extraction, text summarization) can structure and make accessible complex local governance meeting records.
Details
Motivation: Local governance meeting records are dense, bureaucratic documents with significant heterogeneity across municipalities, making them difficult for non-experts to interpret and challenging for automated systems to process, which limits public transparency and civic engagement.Method: Review article synthesizing existing NLP approaches for three core tasks: document segmentation (breaking down lengthy deliberations), domain-specific entity extraction (identifying political actors and personal information), and automatic text summarization (generating concise representations of decision-making processes).
Result: Provides a structured overview of methodological approaches, evaluation metrics, and publicly available resources for applying NLP to governance documents, while highlighting domain-specific challenges like data scarcity, privacy constraints, and source variability.
Conclusion: NLP offers well-established methods to enhance the accessibility and interpretability of governmental records, and this review provides guidance on how computational methods can structure and interpret complex local governance meeting documents.
Abstract: Local governance meeting records are official documents, in the form of minutes or transcripts, documenting how proposals, discussions, and procedural actions unfold during institutional meetings. While generally structured, these documents are often dense, bureaucratic, and highly heterogeneous across municipalities, exhibiting significant variation in language, terminology, structure, and overall organization. This heterogeneity makes them difficult for non-experts to interpret and challenging for intelligent automated systems to process, limiting public transparency and civic engagement. To address these challenges, computational methods can be employed to structure and interpret such complex documents. In particular, Natural Language Processing (NLP) offers well-established methods that can enhance the accessibility and interpretability of governmental records. In this focus article, we review foundational NLP tasks that support the structuring of local governance meeting documents. Specifically, we review three core tasks: document segmentation, domain-specific entity extraction and automatic text summarization, which are essential for navigating lengthy deliberations, identifying political actors and personal information, and generating concise representations of complex decision-making processes. In reviewing these tasks, we discuss methodological approaches, evaluation metrics, and publicly available resources, while highlighting domain-specific challenges such as data scarcity, privacy constraints, and source variability. By synthesizing existing work across these foundational tasks, this article provides a structured overview of how NLP can enhance the structuring and accessibility of local governance meeting records.
[57] LLMs and people both learn to form conventions – just not with each other
Cameron R. Jones, Agnese Lombardi, Kyle Mahowald, Benjamin K. Bergen
Main category: cs.CL
TL;DR: LLMs form communication conventions in same-type dyads (AI-AI) similar to humans, but human-AI pairs fail to align effectively, suggesting fundamental differences in communicative tendencies beyond surface-level mimicry.
Details
Motivation: To investigate whether LLMs form the same kinds of conversational conventions as humans in multimodal communication games, and whether they can align effectively with human partners.Method: Conducted multimodal communication games comparing same-type dyads (human-human, AI-AI) and heterogeneous human-AI pairs. In Experiment 2, tested whether prompting LLMs to produce superficially humanlike behavior improves alignment.
Result: Both humans and LLMs show convention-formation in same-type dyads (increased accuracy, consistency, decreased message length). Human-AI pairs fail to align effectively. Even when LLMs mimic human message length, accuracy and lexical overlap in human-LLM pairs lag behind both human-human and AI-AI pairs.
Conclusion: Conversational alignment requires more than just mimicking previous interactions; it requires shared interpretative biases toward conveyed meanings. LLMs and humans have fundamentally different communicative tendencies that hinder effective cross-type alignment.
Abstract: Humans align to one another in conversation – adopting shared conventions that ease communication. We test whether LLMs form the same kinds of conventions in a multimodal communication game. Both humans and LLMs display evidence of convention-formation (increasing the accuracy and consistency of their turns while decreasing their length) when communicating in same-type dyads (humans with humans, AI with AI). However, heterogenous human-AI pairs fail – suggesting differences in communicative tendencies. In Experiment 2, we ask whether LLMs can be induced to behave more like human conversants, by prompting them to produce superficially humanlike behavior. While the length of their messages matches that of human pairs, accuracy and lexical overlap in human-LLM pairs continues to lag behind that of both human-human and AI-AI pairs. These results suggest that conversational alignment requires more than just the ability to mimic previous interactions, but also shared interpretative biases toward the meanings that are conveyed.
[58] Pretraining with Token-Level Adaptive Latent Chain-of-Thought
Boyi Zeng, Yiqin Hao, He Li, Shixiang Song, Feichen Song, Zitong Wang, Siyuan Huang, Yi Xu, ZiWei He, Xinbing Wang, Zhouhan Lin
Main category: cs.CL
TL;DR: Adaptive latent Chain-of-Thought pretraining that generates variable-length internal reasoning trajectories before each token, with longer trajectories for difficult tokens and shorter/zero for easy ones, improving efficiency and performance.
Details
Motivation: Addressing limitations of scaling LLMs through parameter/data increases by exploring alternative axis: increasing per-token computation without expanding parameters, overcoming constraints of limited high-quality corpora and rising communication costs.Method: Pretraining with Token-Level Adaptive Latent CoT where model generates variable-length latent CoT trajectories before emitting each token, with adaptive halting that allocates longer trajectories to difficult tokens and shorter/zero trajectories to easy ones, emerging naturally from one-stage pretraining on general text.
Result: Experiments with Llama architectures show adaptive latent CoT consistently improves language modeling perplexity and broad downstream accuracy, even with fewer training FLOPs than prior recurrent baselines.
Conclusion: Adaptive latent CoT provides an effective alternative scaling axis by increasing per-token computation without parameter expansion, offering computational efficiency benefits in both training and inference through token-wise adaptive halting.
Abstract: Scaling large language models by increasing parameters and training data is increasingly constrained by limited high-quality corpora and rising communication costs. This work explores an alternative axis: increasing per-token computation without expanding parameters, by internalizing latent Chain-of-Thought (CoT) into pretraining. We propose Pretraining with Token-Level Adaptive Latent CoT (adaptive latent CoT), where the model generates a variable-length latent CoT trajectory before emitting each token – allocating longer trajectories to difficult tokens and shorter (or even zero) trajectories to easy ones. Importantly, this behavior emerges naturally from one-stage pretraining on general text and reduces computation in both training and inference via token-wise adaptive halting. Experiments with Llama architectures show that adaptive latent CoT consistently improves language modeling perplexity and broad downstream accuracy, even with fewer training FLOPs than prior recurrent baselines.
[59] CoRect: Context-Aware Logit Contrast for Hidden State Rectification to Resolve Knowledge Conflicts
Xuhua Ma, Richong Zhang, Zhijie Nie
Main category: cs.CL
TL;DR: CoRect improves RAG faithfulness by identifying and rectifying parametric suppression in deep FFN layers through context-aware logit contrast without needing ground truth.
Details
Motivation: RAG systems often suffer from knowledge conflicts where model parametric knowledge overrides retrieved evidence, leading to unfaithful outputs. Existing approaches are limited to superficial decoding adjustments or weight editing requiring ground-truth targets.Method: CoRect uses layer-wise analysis to identify parametric suppression in deep FFN layers. It contrasts logits from contextualized and non-contextualized forward passes to detect layers with high parametric bias without ground-truth labels, then rectifies hidden states to preserve evidence-grounded information.
Result: Across question answering and summarization benchmarks, CoRect consistently improves faithfulness and reduces hallucinations compared to strong baselines.
Conclusion: CoRect effectively addresses parametric suppression in RAG systems through context-aware logit contrast, improving faithfulness without requiring ground-truth targets.
Abstract: Retrieval-Augmented Generation (RAG) often struggles with knowledge conflicts, where model-internal parametric knowledge overrides retrieved evidence, leading to unfaithful outputs. Existing approaches are often limited, relying either on superficial decoding adjustments or weight editing that necessitates ground-truth targets. Through layer-wise analysis, we attribute this failure to a parametric suppression phenomenon: specifically, in deep layers, certain FFN layers overwrite context-sensitive representations with memorized priors. To address this, we propose CoRect (Context-Aware Logit Contrast for Hidden State Rectification). By contrasting logits from contextualized and non-contextualized forward passes, CoRect identifies layers that exhibit high parametric bias without requiring ground-truth labels. It then rectifies the hidden states to preserve evidence-grounded information. Across question answering (QA) and summarization benchmarks, CoRect consistently improves faithfulness and reduces hallucinations compared to strong baselines.
[60] When Benign Inputs Lead to Severe Harms: Eliciting Unsafe Unintended Behaviors of Computer-Use Agents
Jaylen Jones, Zhehao Zhang, Yuting Ning, Eric Fosler-Lussier, Pierre-Luc St-Charles, Yoshua Bengio, Dawn Song, Yu Su, Huan Sun
Main category: cs.CL
TL;DR: AutoElicit: An agentic framework that systematically discovers unintended harmful behaviors in computer-use agents by iteratively perturbing benign instructions using execution feedback.
Details
Motivation: Computer-use agents (CUAs) can demonstrate unsafe unintended behaviors even under benign inputs, but current risk exploration is anecdotal and lacks systematic methods to proactively surface these long-tail behaviors in realistic scenarios.Method: Proposes AutoElicit framework that iteratively perturbs benign instructions using CUA execution feedback to elicit severe harms while keeping perturbations realistic and benign. The framework automatically surfaces unintended behaviors through systematic exploration.
Result: Surfaced hundreds of harmful unintended behaviors from state-of-the-art CUAs (Claude 4.5 Haiku and Opus). Found persistent susceptibility to unintended behaviors across various frontier CUAs through transferability evaluation of human-verified successful perturbations.
Conclusion: Establishes a foundation for systematically analyzing unintended behaviors in realistic computer-use settings, providing the first conceptual and methodological framework for understanding and proactively discovering these risks.
Abstract: Although computer-use agents (CUAs) hold significant potential to automate increasingly complex OS workflows, they can demonstrate unsafe unintended behaviors that deviate from expected outcomes even under benign input contexts. However, exploration of this risk remains largely anecdotal, lacking concrete characterization and automated methods to proactively surface long-tail unintended behaviors under realistic CUA scenarios. To fill this gap, we introduce the first conceptual and methodological framework for unintended CUA behaviors, by defining their key characteristics, automatically eliciting them, and analyzing how they arise from benign inputs. We propose AutoElicit: an agentic framework that iteratively perturbs benign instructions using CUA execution feedback, and elicits severe harms while keeping perturbations realistic and benign. Using AutoElicit, we surface hundreds of harmful unintended behaviors from state-of-the-art CUAs such as Claude 4.5 Haiku and Opus. We further evaluate the transferability of human-verified successful perturbations, identifying persistent susceptibility to unintended behaviors across various other frontier CUAs. This work establishes a foundation for systematically analyzing unintended behaviors in realistic computer-use settings.
[61] Document Reconstruction Unlocks Scalable Long-Context RLVR
Yao Xiao, Lei Wang, Yue Deng, Guanzheng Chen, Ziqi Jin, Jung-jae Kim, Xiaoli Li, Roy Ka-wei Lee, Lidong Bing
Main category: cs.CL
TL;DR: Unsupervised RL method for enhancing LLM long-context capabilities using paragraph reconstruction tasks without human annotations or teacher models
Details
Motivation: Traditional RLVR requires costly gold-standard answers or evaluation rubrics from teacher models/humans. Need unsupervised approach to enhance LLM long-context capabilities without expensive supervision.Method: Replace paragraphs with placeholders in long documents, train LLMs via RL to reconstruct documents by correctly identifying and sequencing missing paragraphs from candidate options. Captures global narrative coherence.
Result: Method validated on RULER and LongBench v2 benchmarks. Achieves noticeable gains on RULER and reasonable improvement on LongBench v2 without manually curated long-context QA data.
Conclusion: Unsupervised RL approach effectively enhances LLM long-context capabilities without costly supervision. Code, data, and models publicly released.
Abstract: Reinforcement Learning with Verifiable Rewards~(RLVR) has become a prominent paradigm to enhance the capabilities (i.e.\ long-context) of Large Language Models~(LLMs). However, it often relies on gold-standard answers or explicit evaluation rubrics provided by powerful teacher models or human experts, which are costly and time-consuming. In this work, we investigate unsupervised approaches to enhance the long-context capabilities of LLMs, eliminating the need for heavy human annotations or teacher models’ supervision. Specifically, we first replace a few paragraphs with special placeholders in a long document. LLMs are trained through reinforcement learning to reconstruct the document by correctly identifying and sequencing missing paragraphs from a set of candidate options. This training paradigm enables the model to capture global narrative coherence, significantly boosting long-context performance. We validate the effectiveness of our method on two widely used benchmarks, RULER and LongBenchv2. While acquiring noticeable gains on RULER, it can also achieve a reasonable improvement on LongBenchv2 without any manually curated long-context QA data. Furthermore, we conduct extensive ablation studies to analyze the impact of reward design, data curation strategies, training schemes, and data scaling effects on model performance. We publicly release our code, data, and models.
[62] On convexity and efficiency in semantic systems
Nathaniel Imel, Noga Zaslavasky
Main category: cs.CL
TL;DR: The paper analyzes the relationship between convexity and efficiency in human semantic category systems, showing they are distinct properties that often co-occur in color naming due to efficiency optimization rather than convexity being fundamental.
Details
Motivation: To understand the analytical relationship between two widely observed characteristics of human semantic category systems: convex partitions of conceptual spaces and efficiency for communication, which have been observed to co-occur in color naming but whose relationship remains unclear.Method: Combines analytical and empirical analyses using the Information Bottleneck (IB) framework for semantic efficiency, examining convexity and efficiency properties in color naming systems and their ability to discriminate attested systems from hypothetical variants.
Result: Shows that convexity and efficiency are distinct (neither entails the other), but IB-optimal systems are mostly convex in color naming; efficiency is a stronger predictor for discriminating attested color naming systems, with convexity adding negligible improvement; efficiency accounts for empirical phenomena that convexity cannot.
Conclusion: While convexity and efficiency can yield similar structural observations, they are fundamentally distinct properties, with efficiency providing a more comprehensive account of semantic typology than convexity alone.
Abstract: There are two widely held characterizations of human semantic category systems: (1) they form convex partitions of conceptual spaces, and (2) they are efficient for communication. While prior work observed that convexity and efficiency co-occur in color naming, the analytical relation between them and why they co-occur have not been well understood. We address this gap by combining analytical and empirical analyses that build on the Information Bottleneck (IB) framework for semantic efficiency. First, we show that convexity and efficiency are distinct in the sense that neither entails the other: there are convex systems which are inefficient, and optimally-efficient systems that are non-convex. Crucially, however, the IB-optimal systems are mostly convex in the domain of color naming, explaining the main empirical basis for the convexity approach. Second, we show that efficiency is a stronger predictor for discriminating attested color naming systems from hypothetical variants, with convexity adding negligible improvement on top of that. Finally, we discuss a range of empirical phenomena that convexity cannot account for but efficiency can. Taken together, our work suggests that while convexity and efficiency can yield similar structural observations, they are fundamentally distinct, with efficiency providing a more comprehensive account of semantic typology.
[63] Language Predicts Identity Fusion Across Cultures and Reveals Divergent Pathways to Violence
Devin R. Wright, Justin E. Lane, F. LeRon Shults
Main category: cs.CL
TL;DR: A method using cognitive linguistic patterns, LLMs, and implicit metaphor to measure identity fusion from language, which outperforms existing methods and reveals two distinct pathways to extremist violence.
Details
Motivation: To develop a scalable tool for measuring identity fusion (psychological connection to groups) from language to better understand and detect extremism, given increasing polarization and political violence.Method: Cognitive Linguistic Identity Fusion Score (CLIFS) uses cognitive linguistic patterns, large language models, and implicit metaphor analysis to measure identity fusion from text. Validated across UK and Singapore datasets against established fusion measures.
Result: CLIFS outperforms existing methods in predicting validated fusion scores. Applied to extremist manifestos, reveals two distinct high-fusion pathways: ideologues frame themselves in terms of group (kinship bonds), while grievance-driven individuals frame group in terms of personal identity.
Conclusion: The method refines identity fusion theory and provides a scalable tool for fusion research and extremism detection through linguistic analysis.
Abstract: In light of increasing polarization and political violence, understanding the psychological roots of extremism is increasingly important. Prior research shows that identity fusion predicts willingness to engage in extreme acts. We evaluate the Cognitive Linguistic Identity Fusion Score, a method that uses cognitive linguistic patterns, LLMs, and implicit metaphor to measure fusion from language. Across datasets from the United Kingdom and Singapore, this approach outperforms existing methods in predicting validated fusion scores. Applied to extremist manifestos, two distinct high-fusion pathways to violence emerge: ideologues tend to frame themselves in terms of group, forming kinship bonds; whereas grievance-driven individuals frame the group in terms of their personal identity. These results refine theories of identity fusion and provide a scalable tool aiding fusion research and extremism detection.
[64] Language Modeling and Understanding Through Paraphrase Generation and Detection
Jan Philip Wahle
Main category: cs.CL
TL;DR: This thesis proposes decomposing paraphrases into constituent linguistic aspects (paraphrase types) for fine-grained semantic understanding, showing that models trained on paraphrase types outperform binary approaches on tasks like plagiarism detection and duplicate question identification.
Details
Motivation: Current computational language models reduce paraphrasing to binary decisions or single rewrites, obscuring the linguistic factors responsible for meaning preservation. The thesis argues that decomposing paraphrases into their constituent linguistic aspects offers a more fine-grained and cognitively grounded view of semantic equivalence.Method: The approach involves decomposing paraphrases into paraphrase types (constituent linguistic aspects) and training models explicitly on these types rather than treating paraphrasing as a binary classification task.
Result: Models trained on paraphrase types achieve stronger performance: 89.6% accuracy vs 78.4% human baseline for Wikipedia plagiarism detection, 66.5% vs 55.7% for arXiv scientific paper plagiarism, and improved performance on Quora duplicate question identification.
Conclusion: Decomposing paraphrases into linguistic aspects provides a more fine-grained approach to semantic understanding, enabling models to better distinguish meaning-preserving variations and outperform traditional binary approaches on downstream applications.
Abstract: Language enables humans to share knowledge, reason about the world, and pass on strategies for survival and innovation across generations. At the heart of this process is not just the ability to communicate but also the remarkable flexibility in how we can express ourselves. We can express the same thoughts in virtually infinite ways using different words and structures - this ability to rephrase and reformulate expressions is known as paraphrase. Modeling paraphrases is a keystone to meaning in computational language models; being able to construct different variations of texts that convey the same meaning or not shows strong abilities of semantic understanding. If computational language models are to represent meaning, they must understand and control the different aspects that construct the same meaning as opposed to different meanings at a fine granularity. Yet most existing approaches reduce paraphrasing to a binary decision between two texts or to producing a single rewrite of a source, obscuring which linguistic factors are responsible for meaning preservation. In this thesis, I propose that decomposing paraphrases into their constituent linguistic aspects (paraphrase types) offers a more fine-grained and cognitively grounded view of semantic equivalence. I show that even advanced machine learning models struggle with this task. Yet, when explicitly trained on paraphrase types, models achieve stronger performance on related paraphrase tasks and downstream applications. For example, in plagiarism detection, language models trained on paraphrase types surpass human baselines: 89.6% accuracy compared to 78.4% for plagiarism cases from Wikipedia, and 66.5% compared to 55.7% for plagiarism of scientific papers from arXiv. In identifying duplicate questions on Quora, models trained with paraphrase types improve over models trained on binary pairs. Furthermore, I demonstrate that…
[65] New Skills or Sharper Primitives? A Probabilistic Perspective on the Emergence of Reasoning in RLVR
Zhilin Wang, Yafu Li, Shunkai Zhang, Zhi Wang, Haoran Zhang, Xiaoye Qu, Yu Cheng
Main category: cs.CL
TL;DR: RLVR enables LLMs to develop new reasoning capabilities by sharpening atomic step probabilities, overcoming exponential decay in multi-step reasoning chains.
Details
Motivation: To resolve the debate about whether RLVR gives LLMs new capabilities or just elicits latent abilities, proposing that RLVR actually enables new capabilities through probabilistic sharpening of atomic reasoning steps.Method: Proposes a probabilistic framework defining capability by instance-level solvability. Uses Algebrarium framework to train models on single-step operations and evaluate on unseen multi-step tasks. Tests hypothesis that sharpening atomic step probabilities enables overcoming exponential decay in multi-step reasoning.
Result: Empirical results show: (1) RLVR incentivizes exploration of previously inaccessible solution paths; (2) composite performance governed by joint probability of atomic steps (high Pearson correlation ρ∈[0.69,0.96]); (3) RLVR as global optimizer can sacrifice specific skills to maximize aggregate reward.
Conclusion: RLVR enables emergent abilities by iterative optimization of solvable problems, allowing models to develop capabilities for previously unsolvable scenarios through probabilistic sharpening of atomic reasoning steps.
Abstract: Whether Reinforcement Learning with Verifiable Rewards (RLVR) endows Large Language Models (LLMs) with new capabilities or merely elicits latent traces remains a central debate. In this work, we align with the former view, proposing a probabilistic framework where capability is defined by instance-level solvability. We hypothesize that the emergence of complex reasoning can be driven by sharpening atomic step probabilities, which enables models to overcome the exponential decay of success rates inherent in multi-step reasoning chains. Utilizing the Algebrarium framework, we train models exclusively on single-step operations and evaluate their performance on unseen multi-step tasks. Our empirical results confirm that: (1) RLVR incentivizes the exploration of previously inaccessible solution paths by amplifying the model’s existing skills; (2) composite performance is strictly governed by the joint probability of atomic steps, evidenced by high Pearson correlation coefficients ($ρ\in [0.69, 0.96]$); and (3) RLVR, acting as a global optimizer, can cause specific skills to be sacrificed to maximize aggregate reward. Our work offers a novel explanation for emergent abilities in RLVR, suggesting that the iterative optimization of solvable problems enables models to develop the capabilities to tackle previously unsolvable scenarios.
[66] Knowledge Augmented Entity and Relation Extraction for Legal Documents with Hypergraph Neural Network
Binglin Wu, Xianneng Li
Main category: cs.CL
TL;DR: Legal-KAHRE: A hypergraph neural network approach for entity and relation extraction from Chinese drug-related judgment documents, incorporating judicial domain knowledge and specialized case structures.
Details
Motivation: With digitization of Chinese judicial institutions creating large electronic legal document repositories, there's a need for effective entity and relation extraction methods. Existing approaches lack domain-specific knowledge and fail to account for unique judicial domain characteristics, particularly for drug-related cases.Method: 1) Candidate span generator using neighbor-oriented packing strategy and biaffine mechanism; 2) Legal dictionary integration via multi-head attention; 3) Domain-specific case incorporation (joint crimes, combined punishment) into hypergraph structure; 4) Hypergraph neural network for higher-order inference through message passing.
Result: Experimental results on CAIL2022 information extraction dataset show the method significantly outperforms existing baseline models.
Conclusion: The proposed Legal-KAHRE approach effectively addresses the unique challenges of legal document extraction by incorporating judicial domain knowledge and specialized case structures through hypergraph neural networks.
Abstract: With the continuous progress of digitization in Chinese judicial institutions, a substantial amount of electronic legal document information has been accumulated. To unlock its potential value, entity and relation extraction for legal documents has emerged as a crucial task. However, existing methods often lack domain-specific knowledge and fail to account for the unique characteristics of the judicial domain. In this paper, we propose an entity and relation extraction algorithm based on hypergraph neural network (Legal-KAHRE) for drug-related judgment documents. Firstly, we design a candidate span generator based on neighbor-oriented packing strategy and biaffine mechanism, which identifies spans likely to contain entities. Secondly, we construct a legal dictionary with judicial domain knowledge and integrate it into text encoding representation using multi-head attention. Additionally, we incorporate domain-specific cases like joint crimes and combined punishment for multiple crimes into the hypergraph structure design. Finally, we employ a hypergraph neural network for higher-order inference via message passing. Experimental results on the CAIL2022 information extraction dataset demonstrate that our method significantly outperforms existing baseline models.
[67] When Does Context Help? Error Dynamics of Contextual Information in Large Language Models
Dingzirui Wang, Xuanliang Zhang, Keyan Xu, Qingfu Zhu, Wanxiang Che, Yang Deng
Main category: cs.CL
TL;DR: Theoretical framework analyzing how contextual information (demonstrations, retrieved knowledge, history) influences Transformer-based LLMs, showing error decomposition and geometric conditions for improvement.
Details
Motivation: Contextual information at inference time can substantially improve LLMs without parameter updates, but its theoretical role remains poorly understood beyond specific settings like in-context learning.Method: Develops unified theoretical framework for analyzing arbitrary contextual information in Transformer-based LLMs, characterizing contextual influence through output error dynamics. Proves error decomposition in single-layer Transformers and extends to multi-context and multi-layer architectures.
Result: Shows context-conditioned error vector decomposes additively into baseline error plus contextual correction vector. Derives geometric conditions for error reduction and explicit upper bound for contextual correction norm based on context-query relevance and complementarity. Experiments validate theory across ICL, retrieval-augmented generation, and memory evolution.
Conclusion: Provides principled theoretical understanding of contextual information in LLMs, leading to improved context selection strategy that boosts performance by 0.6%.
Abstract: Contextual information at inference time, such as demonstrations, retrieved knowledge, or interaction history, can substantially improve large language models (LLMs) without parameter updates, yet its theoretical role remains poorly understood beyond specific settings such as in-context learning (ICL). We present a unified theoretical framework for analyzing the effect of arbitrary contextual information in Transformer-based LLMs. Our analysis characterizes contextual influence through output error dynamics. In a single-layer Transformer, we prove that the context-conditioned error vector decomposes additively into the baseline error vector and a contextual correction vector. This yields necessary geometric conditions for error reduction: the contextual correction must align with the negative baseline error and satisfy a norm constraint. We further show that the contextual correction norm admits an explicit upper bound determined by context-query relevance and complementarity. These results extend to multi-context and multi-layer Transformers. Experiments across ICL, retrieval-augmented generation, and memory evolution validate our theory and motivate a principled context selection strategy that improves performance by $0.6%$.
[68] JUSTICE: Judicial Unified Synthesis Through Intermediate Conclusion Emulation for Automated Judgment Document Generation
Binglin Wu, Yingyi Zhang, Xiannneg Li
Main category: cs.CL
TL;DR: JUSTICE framework introduces a Pre-Judge phase to legal document generation, emulating human judges’ cognitive workflow to improve legal accuracy and coherence.
Details
Motivation: Existing legal AI methods oversimplify judgment document generation by omitting the crucial Pre-Judge phase where human judges form preliminary conclusions, leading to ineffective acquisition of judicial elements and inadequate modeling of the decision-making process.Method: Proposes JUSTICE framework with three components: Referential Judicial Element Retriever (RJER) retrieves legal articles and precedent cases; Intermediate Conclusion Emulator (ICE) generates verifiable intermediate conclusions; Judicial Unified Synthesizer (JUS) synthesizes inputs to craft final judgments.
Result: JUSTICE significantly outperforms strong baselines on both in-domain legal benchmarks and out-of-distribution datasets, achieving substantial gains in legal accuracy including 4.6% improvement in prison term prediction.
Conclusion: Explicitly modeling the Pre-Judge process is crucial for enhancing legal coherence and accuracy of generated judgment documents, and the JUSTICE framework successfully emulates human judges’ cognitive workflow.
Abstract: Automated judgment document generation is a significant yet challenging legal AI task. As the conclusive written instrument issued by a court, a judgment document embodies complex legal reasoning. However, existing methods often oversimplify this complex process, particularly by omitting the Pre-Judge'' phase, a crucial step where human judges form a preliminary conclusion. This omission leads to two core challenges: 1) the ineffective acquisition of foundational judicial elements, and 2) the inadequate modeling of the Pre-Judge process, which collectively undermine the final document's legal soundness. To address these challenges, we propose \textit{\textbf{J}udicial \textbf{U}nified \textbf{S}ynthesis \textbf{T}hrough \textbf{I}ntermediate \textbf{C}onclusion \textbf{E}mulation} (JUSTICE), a novel framework that emulates the Search $\rightarrow$ Pre-Judge $\rightarrow$ Write’’ cognitive workflow of human judges. Specifically, it introduces the Pre-Judge stage through three dedicated components: Referential Judicial Element Retriever (RJER), Intermediate Conclusion Emulator (ICE), and Judicial Unified Synthesizer (JUS). RJER first retrieves legal articles and a precedent case to establish a referential foundation. ICE then operationalizes the Pre-Judge phase by generating a verifiable intermediate conclusion. Finally, JUS synthesizes these inputs to craft the final judgment. Experiments on both an in-domain legal benchmark and an out-of-distribution dataset show that JUSTICE significantly outperforms strong baselines, with substantial gains in legal accuracy, including a 4.6% improvement in prison term prediction. Our findings underscore the importance of explicitly modeling the Pre-Judge process to enhance the legal coherence and accuracy of generated judgment documents.
[69] Improving Data and Reward Design for Scientific Reasoning in Large Language Models
Zijie Chen, Zhenghao Lin, Xiao Liu, Zhenzhong Lan, Yeyun Gong, Peng Cheng
Main category: cs.CL
TL;DR: Dr. SCI is a dataset and post-training pipeline for improving LLMs’ scientific reasoning on open-ended STEM questions through systematic data processing, curriculum learning, and rubric-guided reinforcement learning.
Details
Motivation: Open-ended science questions are challenging for LLMs due to unreliable supervision and evaluation. Current approaches lack systematic data construction and reward design for scientific post-training.Method: 1) Created Dr. SCI dataset with 1M STEM questions across 8 subjects with verifiable/open-ended splits and difficulty annotations. 2) Dr. SCI post-training pipeline with: Exploration-Expanding SFT to broaden reasoning patterns, Dynamic Difficulty Curriculum for adaptive training, and SciRubric-Guided RL using rubric-based evaluation for stable reinforcement learning.
Result: Qwen3-4B-Base trained with Dr. SCI pipeline achieves 63.2 on GPQA-diamond and 32.4 on GPQA-general, outperforming strong baselines like o1-mini and GPT-4o, showing substantial gains in scientific reasoning, especially for open-ended questions.
Conclusion: The Dr. SCI pipeline effectively improves LLMs’ scientific reasoning capabilities through systematic data processing and specialized post-training techniques, demonstrating significant performance gains on challenging scientific benchmarks.
Abstract: Solving open-ended science questions remains challenging for large language models, particularly due to inherently unreliable supervision and evaluation. The bottleneck lies in the data construction and reward design for scientific post-training. We develop a large-scale, systematic data processing pipeline that transforms heterogeneous open-source science data into Dr. SCI dataset, which comprises of 1M questions across eight STEM subjects, with explicit verifiable/open-ended splits, scalable difficulty annotation, and fine-grained rubrics that operationalize evaluation for open-ended answers. Building on this dataset, we propose the Dr. SCI post-training pipeline, which redesigns the standard SFT -> RL workflow through three components: (i) Exploration-Expanding SFT, which broadens the model’s reasoning pattern coverage prior to RL; (ii) Dynamic Difficulty Curriculum, which adapts training data to the model’s evolving scientific capability; and (iii) SciRubric-Guided RL, which enables stable reinforcement learning on open-ended scientific questions via rubric-based evaluation with explicit answer correctness. Qwen3-4B-Base trained using Dr.SCI pipeline achieves 63.2 on GPQA-diamond and 32.4 on GPQA-general, consistently improves over strong post-trained baselines such as o1-mini and GPT-4o, demonstrating substantial gains in scientific reasoning, especially in open-ended settings.
[70] An Attention-over-Attention Generative Model for Joint Multiple Intent Detection and Slot Filling
Wei Zhu
Main category: cs.CL
TL;DR: A generative framework with attention-over-attention decoder for multi-intent spoken language understanding, addressing both intent detection and slot filling simultaneously.
Details
Motivation: Real-world spoken language understanding needs to handle multiple intents per utterance, but existing methods and datasets focus on single-intent scenarios, creating a gap for practical applications.Method: Proposes a generative framework with attention-over-attention decoder to handle variable number of intents and reduce interference between intent detection and slot filling. Also constructs new multi-intent datasets using BERT’s next sentence prediction head.
Result: Achieves state-of-the-art performance on public datasets (MixATIS and MixSNIPS) and newly constructed datasets.
Conclusion: The proposed attention-over-attention generative model effectively addresses multi-intent SLU challenges and outperforms existing methods on multiple datasets.
Abstract: In task-oriented dialogue systems, spoken language understanding (SLU) is a critical component, which consists of two sub-tasks, intent detection and slot filling. Most existing methods focus on the single-intent SLU, where each utterance only has one intent. However, in real-world scenarios users usually express multiple intents in an utterance, which poses a challenge for existing dialogue systems and datasets. In this paper, we propose a generative framework to simultaneously address multiple intent detection and slot filling. In particular, an attention-over-attention decoder is proposed to handle the variable number of intents and the interference between the two sub-tasks by incorporating an inductive bias into the process of multi-task learning. Besides, we construct two new multi-intent SLU datasets based on single-intent utterances by taking advantage of the next sentence prediction (NSP) head of the BERT model. Experimental results demonstrate that our proposed attention-over-attention generative model achieves state-of-the-art performance on two public datasets, MixATIS and MixSNIPS, and our constructed datasets.
[71] Latent Reasoning with Supervised Thinking States
Ido Amos, Avi Caciularu, Mor Geva, Amir Globerson, Jonathan Herzig, Lior Shani, Idan Szpektor
Main category: cs.CL
TL;DR: Thinking States enables LLMs to perform reasoning concurrently with input processing by generating thought tokens at intervals, transforming them back to embeddings, and adding them to subsequent input tokens, improving efficiency over traditional CoT.
Details
Motivation: Chain-of-thought reasoning in LLMs incurs significant inference costs due to generating long rationales. The authors aim to reduce latency by enabling reasoning to occur while processing input rather than after.Method: Thinking States generates sequences of thinking tokens every few input tokens, transforms these thoughts back into embedding space, and adds them to following input tokens. This captures CoT’s recurrent nature but with parallelizable teacher-forcing learning.
Result: Outperforms other latent reasoning methods on multiple reasoning tasks, narrows gap to CoT on math problems, matches CoT performance on 2-Hop QA with improved latency, and shows stronger reasoning behavior on state-tracking tasks with successful extrapolation to longer sequences.
Conclusion: Thinking States provides an efficient alternative to traditional CoT reasoning by enabling concurrent reasoning during input processing, achieving competitive performance with reduced latency and better generalization to longer sequences.
Abstract: Reasoning with a chain-of-thought (CoT) enables Large Language Models (LLMs) to solve complex tasks but incurs significant inference costs due to the generation of long rationales. We propose Thinking States, a method that performs reasoning {\em while} the input is processing. Specifically, Thinking States generates sequences of thinking tokens every few input tokens, transforms the thoughts back into embedding space, and adds them to the following input tokens. This has two key advantages. First, it captures the recurrent nature of CoT, but where the thought tokens are generated as input is processing. Second, since the thoughts are represented as tokens, they can be learned from natural language supervision, and using teacher-forcing, which is parallelizable. Empirically, Thinking States outperforms other latent reasoning methods on multiple reasoning tasks, narrowing the gap to CoT on math problems, and matching its performance on 2-Hop QA with improved latency. On state-tracking tasks, we show Thinking States leads to stronger reasoning behavior than CoT, successfully extrapolating to longer sequences than seen during training.
[72] UReason: Benchmarking the Reasoning Paradox in Unified Multimodal Models
Cheng Yang, Chufan Shi, Bo Shui, Yaokang Wu, Muzi Tao, Huijuan Wang, Ivan Yee Lee, Yong Liu, Xuezhe Ma, Taylor Berg-Kirkpatrick
Main category: cs.CL
TL;DR: UReason is a diagnostic benchmark for evaluating reasoning-driven image generation, revealing a “Reasoning Paradox” where reasoning traces improve performance but retaining them as context hinders synthesis.
Details
Motivation: To understand the actual effect of chain-of-thought reasoning on visual synthesis in unified multimodal models, as current approaches increasingly adopt reasoning to guide image generation but its impact remains unclear.Method: Created UReason benchmark with 2,000 instances across five reasoning task families. Introduced evaluation framework comparing direct generation, reasoning-guided generation, and de-contextualized generation (conditioning only on refined prompt). Tested across eight open-source unified models.
Result: Discovered consistent “Reasoning Paradox”: reasoning traces improve performance over direct generation, but retaining intermediate thoughts as conditioning context hinders visual synthesis, while conditioning only on refined prompt yields substantial gains. Bottleneck appears to be contextual interference rather than insufficient reasoning capacity.
Conclusion: UReason provides a principled testbed for studying reasoning in unified models and motivates future methods that effectively integrate reasoning for visual generation while mitigating interference from intermediate reasoning context.
Abstract: To elicit capabilities for addressing complex and implicit visual requirements, recent unified multimodal models increasingly adopt chain-of-thought reasoning to guide image generation. However, the actual effect of reasoning on visual synthesis remains unclear. We present UReason, a diagnostic benchmark for reasoning-driven image generation that evaluates whether reasoning can be faithfully executed in pixels. UReason contains 2,000 instances across five task families: Code, Arithmetic, Spatial, Attribute, and Text reasoning. To isolate the role of reasoning traces, we introduce an evaluation framework comparing direct generation, reasoning-guided generation, and de-contextualized generation which conditions only on the refined prompt. Across eight open-source unified models, we observe a consistent Reasoning Paradox: Reasoning traces generally improve performance over direct generation, yet retaining intermediate thoughts as conditioning context often hinders visual synthesis, and conditioning only on the refined prompt yields substantial gains. Our analysis suggests that the bottleneck lies in contextual interference rather than insufficient reasoning capacity. UReason provides a principled testbed for studying reasoning in unified models and motivates future methods that effectively integrate reasoning for visual generation while mitigating interference.
[73] WorldTravel: A Realistic Multimodal Travel-Planning Benchmark with Tightly Coupled Constraints
Zexuan Wang, Chenghao Yang, Yingqi Que, Zhenzhu Yang, Huaqing Yuan, Yiwen Wang, Zhengxuan Jiang, Shengjie Fang, Zhenhe Wu, Zhaohui Wang, Zhixin Yao, Jiashuo Liu, Jincheng Ren, Yuzhen Li, Yang Yang, Jiaheng Liu, Jian Yang, Zaiyuan Wang, Ge Zhang, Zhoufutu Wen, Wenhao Huang
Main category: cs.CL
TL;DR: WorldTravel benchmark introduces real-world travel planning with 15+ interdependent constraints, revealing significant performance collapse in frontier models when moving from text-only to multimodal web environments.
Details
Motivation: Existing benchmarks feature loosely coupled constraints and rely on idealized data, failing to capture the complexity of extracting parameters from dynamic web environments needed for real-world autonomous planning.Method: Created WorldTravel benchmark with 150 real-world travel scenarios across 5 cities requiring navigation of interdependent constraints, and WorldTravel-Webscape multimodal environment with 2,000+ rendered webpages where agents must perceive constraint parameters from visual layouts.
Result: Evaluation of 10 frontier models shows significant performance collapse: GPT-5.2 achieves only 32.67% feasibility in text-only settings, plummeting to 19.33% in multimodal environments. Identified Perception-Action Gap and Planning Horizon threshold at ~10 constraints where reasoning fails.
Conclusion: Perception and reasoning remain independent bottlenecks, underscoring the need for next-generation agents that unify high-fidelity visual perception with long-horizon reasoning for real-world logistics.
Abstract: Real-world autonomous planning requires coordinating tightly coupled constraints where a single decision dictates the feasibility of all subsequent actions. However, existing benchmarks predominantly feature loosely coupled constraints solvable through local greedy decisions and rely on idealized data, failing to capture the complexity of extracting parameters from dynamic web environments. We introduce \textbf{WorldTravel}, a benchmark comprising 150 real-world travel scenarios across 5 cities that demand navigating an average of 15+ interdependent temporal and logical constraints. To evaluate agents in realistic deployments, we develop \textbf{WorldTravel-Webscape}, a multi-modal environment featuring over 2,000 rendered webpages where agents must perceive constraint parameters directly from visual layouts to inform their planning. Our evaluation of 10 frontier models reveals a significant performance collapse: even the state-of-the-art GPT-5.2 achieves only 32.67% feasibility in text-only settings, which plummets to 19.33% in multi-modal environments. We identify a critical Perception-Action Gap and a Planning Horizon threshold at approximately 10 constraints where model reasoning consistently fails, suggesting that perception and reasoning remain independent bottlenecks. These findings underscore the need for next-generation agents that unify high-fidelity visual perception with long-horizon reasoning to handle brittle real-world logistics.
[74] ViGoEmotions: A Benchmark Dataset For Fine-grained Emotion Detection on Vietnamese Texts
Hung Quang Tran, Nam Tien Pham, Son T. Luu, Kiet Van Nguyen
Main category: cs.CL
TL;DR: ViGoEmotions: A Vietnamese emotion corpus with 20,664 social media comments across 27 fine-grained emotions, evaluated with 8 Transformer models and 3 preprocessing strategies showing emoji conversion to text improves most BERT models.
Details
Motivation: To address the need for emotion classification resources in Vietnamese, particularly for social media content, and to study the impact of different preprocessing strategies (especially emoji handling) on emotion classification performance.Method: Created ViGoEmotions corpus with 20,664 Vietnamese social media comments annotated with 27 emotions. Evaluated 8 pre-trained Transformer models (including ViSoBERT, CafeBERT, PhoBERT) under three preprocessing strategies: 1) preserving original emojis with rule-based normalization, 2) converting emojis to textual descriptions, 3) applying ViSoLex lexical normalization system.
Result: Converting emojis to text improved performance for most BERT-based models, while preserving emojis worked best for ViSoBERT and CafeBERT. Removing emojis generally reduced performance. ViSoBERT achieved highest scores (Macro F1: 61.50%, Weighted F1: 63.26%). CafeBERT and PhoBERT also performed strongly.
Conclusion: The ViGoEmotions corpus effectively supports diverse architectures for Vietnamese emotion classification, but preprocessing strategies (especially emoji handling) and annotation quality significantly impact downstream performance.
Abstract: Emotion classification plays a significant role in emotion prediction and harmful content detection. Recent advancements in NLP, particularly through large language models (LLMs), have greatly improved outcomes in this field. This study introduces ViGoEmotions – a Vietnamese emotion corpus comprising 20,664 social media comments in which each comment is classified into 27 fine-grained distinct emotions. To evaluate the quality of the dataset and its impact on emotion classification, eight pre-trained Transformer-based models were evaluated under three preprocessing strategies: preserving original emojis with rule-based normalization, converting emojis into textual descriptions, and applying ViSoLex, a model-based lexical normalization system. Results show that converting emojis into text often improves the performance of several BERT-based baselines, while preserving emojis yields the best results for ViSoBERT and CafeBERT. In contrast, removing emojis generally leads to lower performance. ViSoBERT achieved the highest Macro F1-score of 61.50% and Weighted F1-score of 63.26%. Strong performance was also observed from CafeBERT and PhoBERT. These findings highlight that while the proposed corpus can support diverse architectures effectively, preprocessing strategies and annotation quality remain key factors influencing downstream performance.
[75] Dynamic Long Context Reasoning over Compressed Memory via End-to-End Reinforcement Learning
Zhuoen Chen, Dongfang Li, Meishan Zhang, Baotian Hu, Min Zhang
Main category: cs.CL
TL;DR: A cognitively inspired framework for efficient long-context LLM inference using chunk-wise compression and selective memory recall to overcome computational and memory limitations.
Details
Motivation: LLMs face significant challenges in long-context processing including quadratic computational costs, information forgetting, and context fragmentation in RAG systems. Current methods struggle with efficiency and memory usage when processing very long sequences.Method: Proposes a framework that segments long inputs into chunks, encodes each into compressed memory representations using a learned compressor. A gating module dynamically selects relevant memory blocks, which are processed iteratively by a reasoning module with evolving working memory. Compressor and reasoner are jointly optimized via end-to-end RL, while gating is trained separately as a classifier.
Result: Achieves competitive accuracy on multi-hop reasoning benchmarks (RULER-HQA), extrapolates context length from 7K to 1.75M tokens, offers favorable accuracy-efficiency trade-off. Achieves up to 2× reduction in peak GPU memory usage and 6× inference speedup over MemAgent baseline.
Conclusion: The cognitively inspired approach of chunk-wise compression and selective memory recall provides an effective solution for efficient long-context processing in LLMs, addressing computational and memory limitations while maintaining competitive performance.
Abstract: Large Language Models (LLMs) face significant challenges in long-context processing, including quadratic computational costs, information forgetting, and the context fragmentation inherent in retrieval-augmented generation (RAG). We propose a cognitively inspired framework for efficient long-context inference based on chunk-wise compression and selective memory recall, rather than processing all raw tokens. The framework segments long inputs into chunks and encodes each chunk into compressed memory representations using a learned compressor. A gating module dynamically selects relevant memory blocks, which are then iteratively processed by a reasoning module with an evolving working memory to solve downstream tasks. The compressor and reasoner are jointly optimized via end-to-end reinforcement learning, while the gating module is trained separately as a classifier. Experimental results show that the proposed method achieves competitive accuracy on multi-hop reasoning benchmarks such as RULER-HQA, extrapolates context length from 7K to 1.75M tokens, and offers a favorable accuracy-efficiency trade-off compared to strong long-context baselines. In particular, it achieves up to a 2 times reduction in peak GPU memory usage and a 6 times inference speedup over MemAgent.
[76] TEAM: Temporal-Spatial Consistency Guided Expert Activation for MoE Diffusion Language Model Acceleration
Linye Wei, Zixiang Luo, Pingzhi Tang, Meng Li
Main category: cs.CL
TL;DR: TEAM accelerates Mixture-of-Experts diffusion LLMs by exploiting temporal and spatial consistency in expert routing to reduce activated experts while maintaining performance.
Details
Motivation: MoE diffusion LLMs suffer from inference inefficiency because they activate many experts at each denoising step but only accept a small subset of tokens, creating substantial overhead for latency-sensitive applications.Method: TEAM uses three strategies: 1) conservative expert selection for decoded tokens based on temporal consistency across denoising levels, 2) conservative selection for masked tokens using spatial consistency across positions, and 3) aggressive speculative exploration across multiple candidates to enable more accepted tokens with fewer experts.
Result: TEAM achieves up to 2.2x speedup over vanilla MoE diffusion LLMs with negligible performance degradation.
Conclusion: The proposed TEAM framework effectively addresses the efficiency mismatch in MoE diffusion LLMs by leveraging routing consistency patterns, enabling practical deployment in latency-sensitive scenarios.
Abstract: Diffusion large language models (dLLMs) have recently gained significant attention due to their inherent support for parallel decoding. Building on this paradigm, Mixture-of-Experts (MoE) dLLMs with autoregressive (AR) initialization have further demonstrated strong performance competitive with mainstream AR models. However, we identify a fundamental mismatch between MoE architectures and diffusion-based decoding. Specifically, a large number of experts are activated at each denoising step, while only a small subset of tokens is ultimately accepted, resulting in substantial inference overhead and limiting their deployment in latency-sensitive applications. In this work, we propose TEAM, a plug-and-play framework that accelerates MoE dLLMs by enabling more accepted tokens with fewer activated experts. TEAM is motivated by the observation that expert routing decisions exhibit strong temporal consistency across denoising levels as well as spatial consistency across token positions. Leveraging these properties, TEAM employs three complementary expert activation and decoding strategies, conservatively selecting necessary experts for decoded and masked tokens and simultaneously performing aggressive speculative exploration across multiple candidates. Experimental results demonstrate that TEAM achieves up to 2.2x speedup over vanilla MoE dLLM, with negligible performance degradation. Code is released at https://github.com/PKU-SEC-Lab/TEAM-MoE-dLLM.
[77] Prism: Spectral-Aware Block-Sparse Attention
Xinghao Wang, Pengyu Wang, Xiaoran Liu, Fangxu Liu, Jason Chu, Kai Song, Xipeng Qiu
Main category: cs.CL
TL;DR: Prism is a training-free spectral-aware method for efficient block-sparse attention in long-context LLMs that addresses the inaccuracy of standard coarse-grained attention by decomposing block selection into high/low-frequency branches with energy-based temperature calibration.
Details
Motivation: Existing block-sparse attention methods for accelerating long-context LLM pre-filling suffer from inefficient block identification. Current approaches use coarse-grained attention as a proxy but require expensive token-level operations, creating significant selection overhead. The core problem is that standard mean pooling interacts poorly with Rotary Positional Embeddings, creating a "blind spot" for local positional information.Method: Prism introduces a training-free spectral-aware approach that decomposes block selection into high-frequency and low-frequency branches. It addresses the destructive interference caused by mean pooling with RoPE by applying energy-based temperature calibration to restore attenuated positional signals. This enables block importance estimation using purely block-level operations without token-level searching or scoring.
Result: Extensive evaluations show that Prism maintains accuracy parity with full attention while delivering up to 5.1× speedup. The method effectively overcomes the limitations of standard coarse-grained attention and provides efficient block selection for long-context LLM pre-filling.
Conclusion: Prism offers an effective solution to the block selection bottleneck in block-sparse attention for long-context LLMs. By theoretically analyzing the interaction between mean pooling and RoPE and introducing spectral-aware decomposition with temperature calibration, it achieves both accuracy preservation and significant speed improvements.
Abstract: Block-sparse attention is promising for accelerating long-context LLM pre-filling, yet identifying relevant blocks efficiently remains a bottleneck. Existing methods typically employ coarse-grained attention as a proxy for block importance estimation, but often resort to expensive token-level searching or scoring, resulting in significant selection overhead. In this work, we trace the inaccuracy of standard coarse-grained attention via mean pooling to a theoretical root cause: the interaction between mean pooling and Rotary Positional Embeddings (RoPE). We prove that mean pooling acts as a low-pass filter that induces destructive interference in high-frequency dimensions, effectively creating a “blind spot” for local positional information (e.g., slash patterns). To address this, we introduce Prism, a training-free spectral-aware approach that decomposes block selection into high-frequency and low-frequency branches. By applying energy-based temperature calibration, Prism restores the attenuated positional signals directly from pooled representations, enabling block importance estimation using purely block-level operations, thereby improving efficiency. Extensive evaluations confirm that Prism maintains accuracy parity with full attention while delivering up to $\mathbf{5.1\times}$ speedup.
[78] Large Language Models and Impossible Language Acquisition: “False Promise” or an Overturn of our Current Perspective towards AI
Ziyan wang, Longlong Ma
Main category: cs.CL
TL;DR: Paper examines Chomsky’s critique of LLMs as mere pattern predictors by testing GPT-2 and LSTM models on impossible languages, finding GPT-2 struggles with impossible languages while LSTM aligns with Chomsky’s arguments.
Details
Motivation: To empirically test Chomsky's critique that LLMs cannot distinguish impossible languages due to lacking human-like causal structures, and to examine the theoretical foundations of AI language models.Method: Constructed syntactically impossible languages by applying transformations to English (reversing sentences, adding negation based on word-count parity). Conducted controlled experiments on GPT-2 small models and LSTM models with statistical analysis using Welch’s t-test.
Result: GPT-2 small models underperformed in learning all impossible languages compared to possible languages (p<.001). LSTM models’ performance aligned with Chomsky’s arguments, highlighting differences in transformer architecture evolution.
Conclusion: Proposes new vision within Chomsky’s theory for LLMs and suggests paradigm shift from rationalist-romantic approach to functionalism and empiricism in LLM research, acknowledging architectural differences.
Abstract: In Chomsky’s provocative critique “The False Promise of CHATGPT,” Large Language Models (LLMs) are characterized as mere pattern predictors that do not acquire languages via intrinsic causal and self-correction structures like humans, therefore are not able to distinguish impossible languages. It stands as a representative in a fundamental challenge to the intellectual foundations of AI, for it integrally synthesizes major issues in methodologies within LLMs and possesses an iconic a priori rationalist perspective. We examine this famous critic from both the perspective in pre-existing literature of linguistics and psychology as well as a research based on an experiment inquiring the capacity of learning both possible and impossible languages among LLMs. We constructed a set of syntactically impossible languages by applying certain transformations to English. These include reversing whole sentences, and adding negation based on word-count parity. Two rounds of controlled experiments were each conducted on GPT-2 small models and long short-term memory (LSTM) models. Statistical analysis (Welch’s t-test) shows GPT2 small models underperform in learning all of the impossible languages compared to their performance on the possible language (p<.001). On the other hand, LSTM models’ performance tallies with Chomsky’s argument, suggesting the irreplaceable role of the evolution of transformer architecture. Based on theoretical analysis and empirical findings, we propose a new vision within Chomsky’s theory towards LLMs, and a shift of theoretical paradigm outside Chomsky, from his “rationalist-romantics” paradigm to functionalism and empiricism in LLMs research.
[79] Characterizing, Evaluating, and Optimizing Complex Reasoning
Haoran Zhang, Yafu Li, Zhi Wang, Zhilin Wang, Shunkai Zhang, Xiaoye Qu, Yu Cheng
Main category: cs.CL
TL;DR: TRM introduces a unified framework for evaluating and optimizing reasoning traces in Large Reasoning Models using DAG-based pairwise evaluation and thinking rewards.
Details
Motivation: Existing work lacks unified answers to fundamental questions about reasoning quality definition, evaluation of complex reasoning traces, and using evaluation signals for optimization in Large Reasoning Models.Method: Proposes ME² principle for reasoning quality (macro/micro efficiency/effectiveness), models reasoning traces as DAGs, develops DAG-based pairwise evaluation method, constructs TRM-Preference dataset, and trains Thinking Reward Model (TRM).
Result: Thinking rewards serve as effective optimization signal: test-time selection yields up to 19.3% performance gain, RL training with thinking rewards improves reasoning and performance up to 3.9% across diverse tasks.
Conclusion: Provides unified framework for reasoning evaluation and optimization, demonstrating practical benefits through thinking rewards for enhancing Large Reasoning Models.
Abstract: Large Reasoning Models (LRMs) increasingly rely on reasoning traces with complex internal structures. However, existing work lacks a unified answer to three fundamental questions: (1) what defines high-quality reasoning, (2) how to reliably evaluate long, implicitly structured reasoning traces, and (3) how to use such evaluation signals for reasoning optimization. To address these challenges, we provide a unified perspective. (1) We introduce the ME$^2$ principle to characterize reasoning quality along macro- and micro-level concerning efficiency and effectiveness. (2) Built on this principle, we model reasoning traces as directed acyclic graphs (DAGs) and develop a DAG-based pairwise evaluation method, capturing complex reasoning structures. (3) Based on this method, we construct the TRM-Preference dataset and train a Thinking Reward Model (TRM) to evaluate reasoning quality at scale. Experiments show that thinking rewards serve as an effective optimization signal. At test time, selecting better reasoning leads to better outcomes (up to 19.3% gain), and during RL training, thinking rewards enhance reasoning and performance (up to 3.9% gain) across diverse tasks.
[80] GISA: A Benchmark for General Information-Seeking Assistant
Yutao Zhu, Xingshuo Zhang, Maosen Zhang, Jiajie Jin, Liancheng Zhang, Xiaoshuai Song, Kangzhi Zhao, Wencong Zeng, Ruiming Tang, Han Li, Ji-Rong Wen, Zhicheng Dou
Main category: cs.CL
TL;DR: GISA is a benchmark for evaluating general information-seeking assistants with human-crafted queries, structured answer formats, live updates, and complete search trajectories to address limitations in existing benchmarks.
Details
Motivation: Existing benchmarks for search agents have limitations: they construct queries backward from answers (unnatural tasks), focus on either locating or aggregating information (not both), rely on static answer sets (prone to data contamination), and lack real-world alignment.Method: Introduced GISA benchmark with 373 human-crafted queries reflecting authentic information-seeking scenarios. Features four structured answer formats (item, set, list, table) for deterministic evaluation, integrates deep reasoning and broad information aggregation, includes live subset with periodically updated answers, and provides complete human search trajectories for process-level supervision.
Result: Experiments show even the best-performing model achieves only 19.30% exact match score, with performance degrading on tasks requiring complex planning and comprehensive information gathering, highlighting substantial room for improvement.
Conclusion: GISA addresses key limitations in existing search agent benchmarks and reveals significant gaps in current LLM capabilities for realistic information-seeking tasks, providing a valuable resource for future research and development.
Abstract: The advancement of large language models (LLMs) has significantly accelerated the development of search agents capable of autonomously gathering information through multi-turn web interactions. Various benchmarks have been proposed to evaluate such agents. However, existing benchmarks often construct queries backward from answers, producing unnatural tasks misaligned with real-world needs. Moreover, these benchmarks tend to focus on either locating specific information or aggregating information from multiple sources, while relying on static answer sets prone to data contamination. To bridge these gaps, we introduce GISA, a benchmark for General Information-Seeking Assistants comprising 373 human-crafted queries that reflect authentic information-seeking scenarios. GISA features four structured answer formats (item, set, list, and table), enabling deterministic evaluation. It integrates both deep reasoning and broad information aggregation within unified tasks, and includes a live subset with periodically updated answers to resist memorization. Notably, GISA provides complete human search trajectories for every query, offering gold-standard references for process-level supervision and imitation learning. Experiments on mainstream LLMs and commercial search products reveal that even the best-performing model achieves only 19.30% exact match score, with performance notably degrading on tasks requiring complex planning and comprehensive information gathering. These findings highlight substantial room for future improvement.
[81] How Do Language Models Understand Tables? A Mechanistic Analysis of Cell Location
Xuanliang Zhang, Dingzirui Wang, Keyan Xu, Qingfu Zhu, Wanxiang Che
Main category: cs.CL
TL;DR: LLMs process tables through a three-stage pipeline: semantic binding, coordinate localization via delimiter counting, and information extraction, with column indices encoded in linear subspaces for steering.
Details
Motivation: To understand the opaque internal mechanisms of how LLMs process linearized two-dimensional structured tables, specifically focusing on the atomic task of cell location.Method: Used activation patching and complementary interpretability techniques to dissect table understanding into three stages: Semantic Binding, Coordinate Localization, and Information Extraction.
Result: Models locate target cells via ordinal counting of delimiters, encode column indices in linear subspaces for precise steering, and generalize multi-cell tasks by multiplexing identical attention heads.
Conclusion: Provides a comprehensive explanation of table understanding within Transformer architectures, revealing systematic mechanisms for processing structured data.
Abstract: While Large Language Models (LLMs) are increasingly deployed for table-related tasks, the internal mechanisms enabling them to process linearized two-dimensional structured tables remain opaque. In this work, we investigate the process of table understanding by dissecting the atomic task of cell location. Through activation patching and complementary interpretability techniques, we delineate the table understanding mechanism into a sequential three-stage pipeline: Semantic Binding, Coordinate Localization, and Information Extraction. We demonstrate that models locate the target cell via an ordinal mechanism that counts discrete delimiters to resolve coordinates. Furthermore, column indices are encoded within a linear subspace that allows for precise steering of model focus through vector arithmetic. Finally, we reveal that models generalize to multi-cell location tasks by multiplexing the identical attention heads identified during atomic location. Our findings provide a comprehensive explanation of table understanding within Transformer architectures.
[82] Beyond Scalar Scores: Reinforcement Learning for Error-Aware Quality Estimation of Machine Translation
Archchana Sindhujan, Girish A. Koushik, Shenbin Qian, Diptesh Kanojia, Constantin Orăsan
Main category: cs.CL
TL;DR: ALOPE-RL: A reinforcement learning framework for machine translation quality estimation that uses error-aware rewards from human annotations to train compact LLMs for low-resource language pairs.
Details
Motivation: Current quality estimation approaches rely only on scalar scores without explaining translation errors, and struggle with low-resource languages where annotated data is limited.Method: Introduced first English-Malayalam QE dataset with Direct Assessment scores and Translation Quality Remarks (error descriptions). Developed ALOPE-RL, a policy-based RL framework that trains efficient adapters using rewards from both DA scores and TQR annotations.
Result: ALOPE-RL achieves state-of-the-art performance on English-Malayalam QE using compact LLMs (≤4B parameters) with LoRA and 4-bit quantization, outperforming larger LLM baselines and encoder-based QE models.
Conclusion: Error-aware, policy-based learning enables strong QE performance under limited data and compute budgets, demonstrating the value of incorporating error descriptions beyond numeric scores.
Abstract: Quality Estimation (QE) aims to assess the quality of machine translation (MT) outputs without relying on reference translations, making it essential for real-world, large-scale MT evaluation. Large Language Models (LLMs) have shown significant promise in advancing the field of quality estimation of machine translation. However, most of the QE approaches solely rely on scalar quality scores, offering no explicit information about the translation errors that should drive these judgments. Moreover, for low-resource languages where annotated QE data is limited, existing approaches struggle to achieve reliable performance. To address these challenges, we introduce the first segment-level QE dataset for English to Malayalam, a severely resource-scarce language pair in the QE domain, comprising human-annotated Direct Assessment (DA) scores and Translation Quality Remarks (TQR), which are short, contextual, free-form annotator comments that describe translation errors. We further introduce ALOPE-RL, a policy-based reinforcement learning framework that trains efficient adapters based on policy rewards derived from DA score and TQR. Integrating error-aware rewards with ALOPE-RL, enables LLMs to reason about translation quality beyond numeric scores. Despite being trained on a small-scale QE dataset, ALOPE-RL achieves state-of-the-art performance on English to Malayalam QE using compact LLMs (<=4B parameters}) fine-tuned with LoRA and 4-bit quantization, outperforming both larger LLM-based baselines and leading encoder-based QE models. Our results demonstrate that error-aware, policy-based learning can deliver strong QE performance under limited data and compute budgets. We release our dataset, code, and trained models to support future research.
[83] Do Multilingual LLMs have specialized language heads?
Muhammad Naufil
Main category: cs.CL
TL;DR: The paper investigates whether multilingual LLMs have language-specific attention heads and explores removing heads for unwanted languages to improve deployment efficiency without degrading performance in target languages.
Details
Motivation: Deploying multilingual LLMs in production is inefficient when only a subset of supported languages is needed, but no research exists on identifying language-specific heads in multilingual LLMs (as opposed to translation models).Method: The paper explores whether multilingual LLMs have specialized language attention heads for each language and investigates removing language-specific heads for unwanted languages.
Result: Findings could inform more efficient deployment strategies for multilingual LLMs, enabling reduced model complexity while maintaining high accuracy for targeted languages.
Conclusion: The research addresses an important efficiency gap in multilingual LLM deployment by investigating language-specific head pruning for targeted language subsets.
Abstract: Multilingual large language models (LLMs) have gained significant popularity for their ability to process and generate text across multiple languages. However, deploying these models in production can be inefficient when only a subset of the supported languages is of interest. There has been some research conducted on identifying whether machine translation models have language-specific or language-agnostic heads, however no research has been conducted for multilingual LLMs, to the best of our knowledge, that as we know are capable of performing diverse tasks beyond just translation. This paper explores whether multilingual LLMs have specialized language attention heads for each language, and investigates the possibility of removing language-specific heads for unwanted languages without degrading performance in the targeted languages. Our findings could inform more efficient deployment strategies for multilingual LLMs, enabling reduced model complexity while maintaining high accuracy for targeted languages.
[84] Fundamental Reasoning Paradigms Induce Out-of-Domain Generalization in Language Models
Mingzi Cao, Xingwei Tan, Mahmud Akhter, Marco Valentino, Maria Liakata, Xi Wang, Nikolaos Aletras
Main category: cs.CL
TL;DR: This paper investigates how fundamental reasoning paradigms (deduction, induction, abduction) affect LLM generalization, using symbolic tasks to train models and evaluating on realistic natural language tasks.
Details
Motivation: To systematically explore how fundamental reasoning paradigms (deduction, induction, abduction) influence LLM reasoning behavior and generalization capabilities, moving beyond concrete world knowledge to abstract reasoning skills.Method: 1) Collected new dataset of reasoning trajectories from symbolic tasks targeting each fundamental paradigm; 2) Experimented with various training methods including simple fine-tuning, increasing model depth, and transforming dense models to mixture-of-experts; 3) Evaluated on realistic out-of-domain natural language tasks containing real-world knowledge.
Result: The approach yields strong generalizability with substantial performance gains (up to 14.60 points) across realistic tasks, demonstrating that training on fundamental reasoning paradigms improves LLM reasoning on diverse out-of-domain tasks.
Conclusion: Fundamental reasoning paradigms significantly influence LLM reasoning behavior and generalization, with systematic training on these paradigms leading to substantial performance improvements on realistic natural language reasoning tasks.
Abstract: Deduction, induction, and abduction are fundamental reasoning paradigms, core for human logical thinking. Although improving Large Language Model (LLM) reasoning has attracted significant research efforts, the extent to which the fundamental paradigms induce generalization has yet to be systematically explored. In this study, we shed light on how the interplay between these core paradigms influences LLMs’ reasoning behavior. To this end, we first collect a new dataset of reasoning trajectories from symbolic tasks, each targeting one of the three fundamental paradigms, to abstract from concrete world knowledge. Then, we investigate effective ways for inducing these skills into LLMs. We experiment with a battery of methods including simple fine-tuning, and more complex approaches to increase model depth, or transform a dense model to a mixture-of-experts. We comprehensively evaluate induced models on realistic out-of-domain tasks, that are entirely formulated in natural language and contain real-world knowledge. Our results reveal that our approach yields strong generalizability with substantial performance gains (up to $14.60$) across realistic tasks.
[85] Learning to Judge: LLMs Designing and Applying Evaluation Rubrics
Clemencia Siro, Pourya Aliannejadi, Mohammad Aliannejadi
Main category: cs.CL
TL;DR: LLMs can generate their own evaluation rubrics (GER-Eval) that are interpretable and task-aware, but scoring reliability degrades in factual settings, with closed-source models showing better agreement than open-weight models.
Details
Motivation: Human-defined evaluation rubrics for LLMs are often static and misaligned with how models internally represent language quality. The paper investigates whether LLMs can design and apply their own evaluation rubrics to better align with their internal representations.Method: Introduces GER-Eval (Generating Evaluation Rubrics for Evaluation) to investigate LLM-designed rubrics. Evaluates semantic coherence, scoring reliability, and alignment with human criteria across different LLMs including GPT-4o and Llama models.
Result: LLMs reliably generate interpretable, task-aware evaluation dimensions and apply them consistently within models. However, scoring reliability degrades in factual and knowledge-intensive settings. Closed-source models (GPT-4o) achieve higher agreement and cross-model generalization than open-weight models (Llama).
Conclusion: Evaluation is a learned linguistic capability of LLMs, consistent within models but fragmented across them. Calls for new methods that jointly model human and LLM evaluative language to improve reliability and interpretability.
Abstract: Large language models (LLMs) are increasingly used as evaluators for natural language generation, applying human-defined rubrics to assess system outputs. However, human rubrics are often static and misaligned with how models internally represent language quality. We introduce GER-Eval (Generating Evaluation Rubrics for Evaluation) to investigate whether LLMs can design and apply their own evaluation rubrics. We evaluate the semantic coherence and scoring reliability of LLM-defined criteria and their alignment with human criteria. LLMs reliably generate interpretable and task-aware evaluation dimensions and apply them consistently within models, but their scoring reliability degrades in factual and knowledge-intensive settings. Closed-source models such as GPT-4o achieve higher agreement and cross-model generalization than open-weight models such as Llama. Our findings position evaluation as a learned linguistic capability of LLMs, consistent within models but fragmented across them, and call for new methods that jointly model human and LLM evaluative language to improve reliability and interpretability.
[86] Old wine in old glasses: Comparing computational and qualitative methods in identifying incivility on Persian Twitter during the #MahsaAmini movement
Hossein Kermani, Fatemeh Oudlajani, Pardis Yarahmadi, Hamideh Mahdi Soltani, Mohammad Makki, Zahra HosseiniKhoo
Main category: cs.CL
TL;DR: Comparison of incivility detection methods in Persian tweets using human coding, ParsBERT, and ChatGPT on #MahsaAmini data
Details
Motivation: To evaluate and compare different approaches for detecting hate speech and incivility in Persian tweets, particularly in low-resource language contexts, using the #MahsaAmini movement as a case studyMethod: Three approaches compared: 1) Human qualitative coding, 2) Supervised learning with ParsBERT (Persian BERT), 3) Large language models (ChatGPT with 7 different models). Evaluation on 47,278 Persian tweets from the #MahsaAmini movement in Iran
Result: ParsBERT substantially outperformed all seven ChatGPT models in identifying hate speech. ChatGPT struggled with both subtle cases and explicitly uncivil content. Prompt language (English vs. Persian) did not meaningfully affect ChatGPT outputs
Conclusion: The study provides detailed comparison of approaches for hate speech analysis in low-resource languages, showing ParsBERT’s superiority over ChatGPT for this specific task, and clarifies strengths/limitations of each method
Abstract: This paper compares three approaches to detecting incivility in Persian tweets: human qualitative coding, supervised learning with ParsBERT, and large language models (ChatGPT). Using 47,278 tweets from the #MahsaAmini movement in Iran, we evaluate the accuracy and efficiency of each method. ParsBERT substantially outperforms seven evaluated ChatGPT models in identifying hate speech. We also find that ChatGPT struggles not only with subtle cases but also with explicitly uncivil content, and that prompt language (English vs. Persian) does not meaningfully affect its outputs. The study provides a detailed comparison of these approaches and clarifies their strengths and limitations for analyzing hate speech in a low-resource language context.
[87] Challenges in Translating Technical Lectures: Insights from the NPTEL
Basudha Raje, Sadanand Venkatraman, Nandana TP, Soumyadeepa Das, Polkam Poojitha, M. Vijaykumar, Tanima Bagchi, Hema A. Murthy
Main category: cs.CL
TL;DR: Analysis of machine translation for Indian languages (Bangla, Malayalam, Telugu) in educational contexts, focusing on evaluation challenges for morphologically rich languages.
Details
Motivation: To examine practical applications of machine translation for Indian languages in educational technology under NEP 2020, addressing the need for multilingual accommodation in diverse linguistic contexts using NPTEL MOOC content.Method: Uses NPTEL MOOC portal as corpus, curates spontaneous speech corpora for technical concepts, analyzes machine translation performance across Bangla, Malayalam, and Telugu with focus on evaluation metrics.
Result: Reveals metric-specific sensitivity and challenges with morphologically rich and semantically compact language features when tested against surface overlapping metrics.
Conclusion: Highlights the need for better evaluation frameworks for machine translation in Indian languages, particularly for educational content delivery in diverse linguistic settings.
Abstract: This study examines the practical applications and methodological implications of Machine Translation in Indian Languages, specifically Bangla, Malayalam, and Telugu, within emerging translation workflows and in relation to existing evaluation frameworks. The choice of languages prioritized in this study is motivated by a triangulation of linguistic diversity, which illustrates the significance of multilingual accommodation of educational technology under NEP 2020. This is further supported by the largest MOOC portal, i.e., NPTEL, which has served as a corpus to facilitate the arguments presented in this paper. The curation of a spontaneous speech corpora that accounts for lucid delivery of technical concepts, considering the retention of suitable register and lexical choices are crucial in a diverse country like India. The findings of this study highlight metric-specific sensitivity and the challenges of morphologically rich and semantically compact features when tested against surface overlapping metrics.
[88] Do Images Clarify? A Study on the Effect of Images on Clarifying Questions in Conversational Search
Clemencia Siro, Zahra Abbasiantaeb, Yifei Yuan, Mohammad Aliannejadi, Maarten de Rijke
Main category: cs.CL
TL;DR: Multimodal clarifying questions with images improve user engagement and query precision in conversational search, but benefits are task-dependent and vary with user expertise.
Details
Motivation: While text-based clarifying questions have been shown to improve conversational search, the impact of incorporating images into clarifying questions remains unexplored, particularly for user performance in different search tasks.Method: Conducted a user study with 73 participants comparing multimodal (text+images) vs. text-only clarifying questions in conversational search, examining effects on two tasks: answering clarifying questions and query reformulation.
Result: Participants preferred multimodal questions for answering clarifying questions but preferences were balanced for query reformulation. Images helped maintain engagement across expertise levels for question answering, and led to more precise queries and better retrieval performance for reformulation. Text-only setups performed better for question answering due to more comprehensive textual information.
Conclusion: Benefits of visual augmentation in conversational search are task-dependent and should be strategically implemented based on specific search context and user characteristics, providing valuable insights for designing effective multimodal conversational search systems.
Abstract: Conversational search systems increasingly employ clarifying questions to refine user queries and improve the search experience. Previous studies have demonstrated the usefulness of text-based clarifying questions in enhancing both retrieval performance and user experience. While images have been shown to improve retrieval performance in various contexts, their impact on user performance when incorporated into clarifying questions remains largely unexplored. We conduct a user study with 73 participants to investigate the role of images in conversational search, specifically examining their effects on two search-related tasks: (i) answering clarifying questions and (ii) query reformulation. We compare the effect of multimodal and text-only clarifying questions in both tasks within a conversational search context from various perspectives. Our findings reveal that while participants showed a strong preference for multimodal questions when answering clarifying questions, preferences were more balanced in the query reformulation task. The impact of images varied with both task type and user expertise. In answering clarifying questions, images helped maintain engagement across different expertise levels, while in query reformulation they led to more precise queries and improved retrieval performance. Interestingly, for clarifying question answering, text-only setups demonstrated better user performance as they provided more comprehensive textual information in the absence of images. These results provide valuable insights for designing effective multimodal conversational search systems, highlighting that the benefits of visual augmentation are task-dependent and should be strategically implemented based on the specific search context and user characteristics.
[89] FactSim: Fact-Checking for Opinion Summarization
Leandro Anghinoni, Jorge Sanchez
Main category: cs.CL
TL;DR: Proposes a novel automated methodology for evaluating factual consistency in opinion summarization by measuring similarity between claims in generated summaries and original reviews, addressing limitations of traditional metrics with LLMs.
Details
Motivation: Traditional automated metrics for evaluating generative AI in opinion summarization have limitations due to the paradigm shift introduced by large language models, requiring more comprehensive and precise evaluation techniques for factual consistency assessment.Method: Develops a fully automated methodology that extracts factual assessments from texts, measures similarity between claims in generated summaries and original reviews, and computes coverage and consistency scores based on claim comparison.
Result: The proposed metric attributes higher scores to similar claims regardless of negation, paraphrasing, or expansion, and shows high correlation with human judgment compared to state-of-the-art metrics.
Conclusion: The novel automated evaluation method effectively addresses limitations of traditional metrics for assessing factual consistency in opinion summarization tasks with LLMs.
Abstract: We explore the need for more comprehensive and precise evaluation techniques for generative artificial intelligence (GenAI) in text summarization tasks, specifically in the area of opinion summarization. Traditional methods, which leverage automated metrics to compare machine-generated summaries from a collection of opinion pieces, e.g. product reviews, have shown limitations due to the paradigm shift introduced by large language models (LLM). This paper addresses these shortcomings by proposing a novel, fully automated methodology for assessing the factual consistency of such summaries. The method is based on measuring the similarity between the claims in a given summary with those from the original reviews, measuring the coverage and consistency of the generated summary. To do so, we rely on a simple approach to extract factual assessment from texts that we then compare and summarize in a suitable score. We demonstrate that the proposed metric attributes higher scores to similar claims, regardless of whether the claim is negated, paraphrased, or expanded, and that the score has a high correlation to human judgment when compared to state-of-the-art metrics.
[90] PERSPECTRA: A Scalable and Configurable Pluralist Benchmark of Perspectives from Arguments
Shangrui Nie, Kian Omoomi, Lucie Flek, Zhixue Zhao, Charles Welch
Main category: cs.CL
TL;DR: PERSPECTRA is a pluralism benchmark combining structured Kialo debate graphs with diverse Reddit discussions to evaluate LLMs’ ability to handle multiple perspectives.
Details
Motivation: Current LLMs lack pluralism - the capacity to engage with diverse perspectives without collapsing them into a single viewpoint. Existing debate sources have limitations: Reddit has linguistic diversity but lacks structure, while Kialo has structure but is overly concise and detached from natural discourse.Method: Created PERSPECTRA benchmark using controlled retrieval-and-expansion pipeline to integrate Kialo debate graphs with Reddit discussions. Constructed 3,810 enriched arguments spanning 762 pro/con stances on 100 controversial topics, with each opinion expanded to multiple naturalistic variants.
Result: State-of-the-art LLMs show systematic failures: overestimating number of viewpoints, misclassifying concessive structures, and struggling with pluralism-aware understanding and reasoning across three tasks (opinion counting, opinion matching, and polarity check).
Conclusion: PERSPECTRA establishes the first scalable, configurable benchmark for evaluating how well models represent, distinguish, and reason over multiple perspectives, addressing a critical gap in LLM alignment research.
Abstract: Pluralism, the capacity to engage with diverse perspectives without collapsing them into a single viewpoint, is critical for developing large language models that faithfully reflect human heterogeneity. Yet this characteristic has not been carefully examined in the LLM research community and remains absent from most alignment studies. Debate-oriented sources provide a natural entry point for pluralism research. Previous work builds on online debate sources but remains constrained by costly human validation. Other debate-rich platforms such as Reddit and Kialo also offer promising material: Reddit provides linguistic diversity and scale but lacks clear argumentative structure, while Kialo supplies explicit pro/con graphs but remains overly concise and detached from natural discourse. We introduce PERSPECTRA, a pluralist benchmark that integrates the structural clarity of Kialo debate graphs with the linguistic diversity of real Reddit discussions. Using a controlled retrieval-and-expansion pipeline, we construct 3,810 enriched arguments spanning 762 pro/con stances on 100 controversial topics. Each opinion is expanded to multiple naturalistic variants, enabling robust evaluation of pluralism. We initialise three tasks with PERSPECTRA: opinion counting (identifying distinct viewpoints), opinion matching (aligning supporting stances and discourse to source opinions), and polarity check (inferring aggregate stance in mixed discourse). Experiments with state-of-the-art open-source and proprietary LLMs, highlight systematic failures, such as overestimating the number of viewpoints and misclassifying concessive structures, underscoring the difficulty of pluralism-aware understanding and reasoning. By combining diversity with structure, PERSPECTRA establishes the first scalable, configurable benchmark for evaluating how well models represent, distinguish, and reason over multiple perspectives.
[91] Map of Encoders – Mapping Sentence Encoders using Quantum Relative Entropy
Gaifan Zhang, Danushka Bollegala
Main category: cs.CL
TL;DR: A method to create a visual map of 1101 sentence encoders by representing each encoder using embedding matrices, computing Pairwise Inner Product matrices, and deriving feature vectors based on Quantum Relative Entropy with respect to a unit base encoder.
Details
Motivation: To provide a comprehensive visualization and comparison framework for the growing landscape of pre-trained sentence encoders, enabling researchers to understand relationships between different encoders and predict their downstream task performance.Method: 1) Represent each sentence encoder using an embedding matrix from a sentence set; 2) Compute Pairwise Inner Product (PIP) matrices for each encoder; 3) Create feature vectors using Quantum Relative Entropy (QRE) with respect to a unit base encoder; 4) Construct a 2D map of 1101 publicly available encoders.
Result: Successfully created a comprehensive map of 1101 sentence encoders where encoders with similar attributes are proximally located. The encoder feature vectors accurately predict downstream task performance in retrieval and clustering tasks, demonstrating the faithfulness of the map.
Conclusion: The proposed method provides a novel perspective on the sentence encoder landscape, enabling effective comparison, visualization, and performance prediction of diverse sentence encoders at scale.
Abstract: We propose a method to compare and visualise sentence encoders at scale by creating a map of encoders where each sentence encoder is represented in relation to the other sentence encoders. Specifically, we first represent a sentence encoder using an embedding matrix of a sentence set, where each row corresponds to the embedding of a sentence. Next, we compute the Pairwise Inner Product (PIP) matrix for a sentence encoder using its embedding matrix. Finally, we create a feature vector for each sentence encoder reflecting its Quantum Relative Entropy (QRE) with respect to a unit base encoder. We construct a map of encoders covering 1101 publicly available sentence encoders, providing a new perspective of the landscape of the pre-trained sentence encoders. Our map accurately reflects various relationships between encoders, where encoders with similar attributes are proximally located on the map. Moreover, our encoder feature vectors can be used to accurately infer downstream task performance of the encoders, such as in retrieval and clustering tasks, demonstrating the faithfulness of our map.
[92] LakeHopper: Cross Data Lakes Column Type Annotation through Model Adaptation
Yushi Sun, Xujia Li, Nan Tang, Quanqing Xu, Chuanhui Yang, Lei Chen
Main category: cs.CL
TL;DR: LakeHopper: A framework for adapting pre-trained language models for column type annotation across different data lakes with minimal target annotations
Details
Motivation: Current column type annotation solutions require resource-intensive fine-tuning on well-annotated columns from specific data lakes, making adaptation to new data lakes annotation-heavy. The paper addresses the challenge of adapting existing models to new data lakes with minimal annotations.Method: LakeHopper identifies and resolves knowledge gaps through LM interactions, uses cluster-based data selection for unannotated columns, and employs incremental fine-tuning to gradually adapt source models to target data lakes while preserving shared knowledge.
Result: Experimental results validate LakeHopper’s effectiveness on two different data lake transfers under both low-resource and high-resource settings, demonstrating successful adaptation with minimal target annotations.
Conclusion: LakeHopper provides an effective framework for adapting column type annotation models across data lakes with reduced annotation requirements, addressing source-target knowledge gaps and preserving shared knowledge.
Abstract: Column type annotation is vital for tasks like data cleaning, integration, and visualization. Recent solutions rely on resource-intensive language models fine-tuned on well-annotated columns from a particular set of tables, i.e., a source data lake. In this paper, we study whether we can adapt an existing pre-trained LM-based model to a new (i.e., target) data lake to minimize the annotations required on the new data lake. However, challenges include the source-target knowledge gap, selecting informative target data, and fine-tuning without losing shared knowledge exist. We propose LakeHopper, a framework that identifies and resolves the knowledge gap through LM interactions, employs a cluster-based data selection scheme for unannotated columns, and uses an incremental fine-tuning mechanism that gradually adapts the source model to the target data lake. Our experimental results validate the effectiveness of LakeHopper on two different data lake transfers under both low-resource and high-resource settings.
[93] Affective Flow Language Model for Emotional Support Conversation
Chenghui Zou, Ning Wang, Tiesunlong Shen, Luwei Xiao, Chuan Ma, Xiangpeng Li, Rui Mao, Erik Cambria
Main category: cs.CL
TL;DR: AFlow introduces affective flow modeling for emotional support conversations, using continuous supervision on dialogue prefixes to improve multi-turn strategy decisions and response quality.
Details
Motivation: Existing LLMs for emotional support conversation rely on sparse outcome-level signals, offering limited supervision for intermediate strategy decisions in complex multi-turn support scenarios.Method: Proposes AFlow framework that models continuous affective flow along multi-turn trajectories, estimates intermediate utility over searched trajectories, learns preference-consistent strategy transitions, and uses subpath-level flow-balance objective to propagate preference signals to intermediate states.
Result: Consistent and significant improvements over competitive baselines in diverse emotional contexts. AFlow with compact open-source backbone outperforms proprietary LLMs like GPT-4o and Claude-3.5 on major ESC metrics.
Conclusion: Affective flow modeling provides effective fine-grained supervision for emotional support conversations, enabling better strategy coherence and empathetic response quality in multi-turn dialogues.
Abstract: Large language models (LLMs) have been widely applied to emotional support conversation (ESC). However, complex multi-turn support remains challenging.This is because existing alignment schemes rely on sparse outcome-level signals, thus offering limited supervision for intermediate strategy decisions. To fill this gap, this paper proposes affective flow language model for emotional support conversation (AFlow), a framework that introduces fine-grained supervision on dialogue prefixes by modeling a continuous affective flow along multi-turn trajectories. AFlow can estimate intermediate utility over searched trajectories and learn preference-consistent strategy transitions. To improve strategy coherence and empathetic response quality, a subpath-level flow-balance objective is presented to propagate preference signals to intermediate states. Experiment results show consistent and significant improvements over competitive baselines in diverse emotional contexts. Remarkably, AFlow with a compact open-source backbone outperforms proprietary LMMs such as GPT-4o and Claude-3.5 on major ESC metrics. Our code is available at https://github.com/chzou25-lgtm/AffectiveFlow.
[94] WildReward: Learning Reward Models from In-the-Wild Human Interactions
Hao Peng, Yunjia Qi, Xiaozhi Wang, Zijun Yao, Lei Hou, Juanzi Li
Main category: cs.CL
TL;DR: WildReward: Training reward models directly from in-the-wild LLM interactions without human-annotated preference pairs, using ordinal regression on user feedback from WildChat.
Details
Motivation: Traditional reward models require large-scale human-annotated preference pairs, which are expensive to collect. With widespread LLM deployment, in-the-wild interactions provide rich implicit reward signals that could be leveraged to develop reward models more efficiently.Method: Uses WildChat as interaction source, proposes pipeline to extract reliable human feedback, yielding 186k high-quality instances. Trains WildReward via ordinal regression directly on user feedback without preference pairs.
Result: WildReward achieves comparable or superior performance to conventional reward models, with improved calibration and cross-sample consistency. Benefits from user diversity (more users yield stronger models). Applied to online DPO training with significant improvements across various tasks.
Conclusion: In-the-wild interactions can effectively replace human-annotated preference pairs for training reward models, offering a scalable and efficient alternative with strong performance.
Abstract: Reward models (RMs) are crucial for the training of large language models (LLMs), yet they typically rely on large-scale human-annotated preference pairs. With the widespread deployment of LLMs, in-the-wild interactions have emerged as a rich source of implicit reward signals. This raises the question: Can we develop reward models directly from in-the-wild interactions? In this work, we explore this possibility by adopting WildChat as an interaction source and proposing a pipeline to extract reliable human feedback, yielding 186k high-quality instances for training WildReward via ordinal regression directly on user feedback without preference pairs. Extensive experiments demonstrate that WildReward achieves comparable or even superior performance compared to conventional reward models, with improved calibration and cross-sample consistency. We also observe that WildReward benefits directly from user diversity, where more users yield stronger reward models. Finally, we apply WildReward to online DPO training and observe significant improvements across various tasks. Code and data are released at https://github.com/THU-KEG/WildReward.
[95] Understanding Dynamic Compute Allocation in Recurrent Transformers
Ibraheem Muhammad Moosa, Suhas Lohit, Ye Wang, Moitreya Chatterjee, Wenpeng Yin
Main category: cs.CL
TL;DR: ANIRA is a recurrent Transformer framework for token-level adaptive computation that enables systematic analysis of compute allocation alignment with task complexity, generalization, and decision timing using algorithmic tasks with parameterized difficulty.
Details
Motivation: Prior work on token-level adaptive computation lacks proper evaluation due to unobservable token-level difficulty in natural language benchmarks and confounding architectural factors, making it unclear whether compute allocation truly aligns with underlying complexity.Method: Introduces ANIRA, a unified recurrent Transformer framework supporting per-token variable-depth computation while isolating compute allocation decisions from other model factors. Uses algorithmic and synthetic language tasks with parameterized difficulty for complexity-controlled evaluation.
Result: Compute allocation aligned with task complexity can emerge without explicit difficulty supervision, but such alignment doesn’t guarantee algorithmic generalization (models fail to extrapolate to unseen input sizes). Early compute decisions rely on static structural cues, while online halting more closely tracks algorithmic execution state.
Conclusion: The paper provides a systematic framework for evaluating token-level adaptive computation, revealing important insights about compute allocation alignment, generalization limitations, and decision timing mechanisms in adaptive models.
Abstract: Token-level adaptive computation seeks to reduce inference cost by allocating more computation to harder tokens and less to easier ones. However, prior work is primarily evaluated on natural-language benchmarks using task-level metrics, where token-level difficulty is unobservable and confounded with architectural factors, making it unclear whether compute allocation truly aligns with underlying complexity. We address this gap through three contributions. First, we introduce a complexity-controlled evaluation paradigm using algorithmic and synthetic language tasks with parameterized difficulty, enabling direct testing of token-level compute allocation. Second, we propose ANIRA, a unified recurrent Transformer framework that supports per-token variable-depth computation while isolating compute allocation decisions from other model factors. Third, we use this framework to conduct a systematic analysis of token-level adaptive computation across alignment with complexity, generalization, and decision timing. Our results show that compute allocation aligned with task complexity can emerge without explicit difficulty supervision, but such alignment does not imply algorithmic generalization: models fail to extrapolate to unseen input sizes despite allocating additional computation. We further find that early compute decisions rely on static structural cues, whereas online halting more closely tracks algorithmic execution state.
[96] Large Language Models for Geolocation Extraction in Humanitarian Crisis Response
G. Cafferata, T. Demarco, K. Kalimeri, Y. Mejova, M. G. Beiró
Main category: cs.CL
TL;DR: LLM-based framework improves fairness and accuracy of location extraction from humanitarian texts, reducing geographic biases in crisis analytics.
Details
Motivation: Humanitarian crisis response requires accurate geographic information, but existing automated systems reproduce geographic and socioeconomic biases, leading to uneven visibility of crisis-affected regions.Method: Two-step framework combining few-shot LLM-based named entity recognition with agent-based geocoding module that uses context to resolve ambiguous toponyms.
Result: LLM-based methods substantially improve both precision and fairness of geolocation extraction, particularly for underrepresented regions, outperforming state-of-the-art pretrained and rule-based systems.
Conclusion: The work bridges LLM reasoning with responsible AI principles to create more equitable geospatial data systems for humanitarian response, advancing the goal of inclusive crisis analytics.
Abstract: Humanitarian crises demand timely and accurate geographic information to inform effective response efforts. Yet, automated systems that extract locations from text often reproduce existing geographic and socioeconomic biases, leading to uneven visibility of crisis-affected regions. This paper investigates whether Large Language Models (LLMs) can address these geographic disparities in extracting location information from humanitarian documents. We introduce a two-step framework that combines few-shot LLM-based named entity recognition with an agent-based geocoding module that leverages context to resolve ambiguous toponyms. We benchmark our approach against state-of-the-art pretrained and rule-based systems using both accuracy and fairness metrics across geographic and socioeconomic dimensions. Our evaluation uses an extended version of the HumSet dataset with refined literal toponym annotations. Results show that LLM-based methods substantially improve both the precision and fairness of geolocation extraction from humanitarian texts, particularly for underrepresented regions. By bridging advances in LLM reasoning with principles of responsible and inclusive AI, this work contributes to more equitable geospatial data systems for humanitarian response, advancing the goal of leaving no place behind in crisis analytics.
[97] Is Reasoning Capability Enough for Safety in Long-Context Language Models?
Yu Fu, Haz Sameen Shahgir, Huanli Gong, Zhipeng Wei, N. Benjamin Erichson, Yue Dong
Main category: cs.CL
TL;DR: Stronger reasoning capabilities in LLMs don’t improve safety against compositional reasoning attacks where harmful intent emerges only after combining scattered fragments in long contexts.
Details
Motivation: To test whether stronger reasoning capability improves safety in long-context settings where harmful intent is implicit and must be inferred through reasoning.Method: Introduces compositional reasoning attacks where harmful queries are decomposed into incomplete fragments scattered throughout long contexts (up to 64k tokens), then prompts models with neutral reasoning queries that induce retrieval and synthesis. Evaluates 14 frontier LLMs.
Result: Three key findings: (1) Models with stronger general reasoning capability are not more robust to attacks, often assembling harmful intent yet failing to refuse; (2) Safety alignment degrades as context length increases; (3) Increasing inference-time compute reduces attack success by over 50 percentage points on GPT-oss-120b.
Conclusion: Safety does not automatically scale with reasoning capability, especially under long-context inference, revealing a critical vulnerability in current LLM safety approaches.
Abstract: Large language models (LLMs) increasingly combine long-context processing with advanced reasoning, enabling them to retrieve and synthesize information distributed across tens of thousands of tokens. A hypothesis is that stronger reasoning capability should improve safety by helping models recognize harmful intent even when it is not stated explicitly. We test this hypothesis in long-context settings where harmful intent is implicit and must be inferred through reasoning, and find that it does not hold. We introduce compositional reasoning attacks, a new threat model in which a harmful query is decomposed into incomplete fragments that scattered throughout a long context. The model is then prompted with a neutral reasoning query that induces retrieval and synthesis, causing the harmful intent to emerge only after composition. Evaluating 14 frontier LLMs on contexts up to 64k tokens, we uncover three findings: (1) models with stronger general reasoning capability are not more robust to compositional reasoning attacks, often assembling the intent yet failing to refuse; (2) safety alignment consistently degrades as context length increases; and (3) inference-time reasoning effort is a key mitigating factor: increasing inference-time compute reduces attack success by over 50 percentage points on GPT-oss-120b model. Together, these results suggest that safety does not automatically scale with reasoning capability, especially under long-context inference.
[98] GitSearch: Enhancing Community Notes Generation with Gap-Informed Targeted Search
Sahajpreet Singh, Kokil Jaidka, Min-Yen Kan
Main category: cs.CL
TL;DR: GitSearch framework uses human-perceived quality gaps as signals to improve community-based moderation through targeted web retrieval and note synthesis, achieving better coverage and helpfulness than existing methods.
Details
Motivation: Community-based moderation offers scalable alternative to centralized fact-checking but faces structural challenges and AI methods fail in "cold start" scenarios where there's insufficient data.Method: Three-stage pipeline: 1) identifying information deficits (quality gaps), 2) executing real-time targeted web retrieval to resolve gaps, 3) synthesizing platform-compliant notes. Uses PolBench benchmark of 78,698 political tweets with Community Notes for evaluation.
Result: Achieves 99% coverage (almost doubling state-of-the-art), surpasses human-authored helpful notes with 69% win rate and superior helpfulness scores (3.87 vs 3.36), demonstrating effective retrieval that balances scale and quality.
Conclusion: GitSearch effectively addresses cold start problems in community moderation by treating quality gaps as first-class signals, enabling scalable, high-quality fact-checking through targeted information retrieval.
Abstract: Community-based moderation offers a scalable alternative to centralized fact-checking, yet it faces significant structural challenges, and existing AI-based methods fail in “cold start” scenarios. To tackle these challenges, we introduce GitSearch (Gap-Informed Targeted Search), a framework that treats human-perceived quality gaps, such as missing context, etc., as first-class signals. GitSearch has a three-stage pipeline: identifying information deficits, executing real-time targeted web-retrieval to resolve them, and synthesizing platform-compliant notes. To facilitate evaluation, we present PolBench, a benchmark of 78,698 U.S. political tweets with their associated Community Notes. We find GitSearch achieves 99% coverage, almost doubling coverage over the state-of-the-art. GitSearch surpasses human-authored helpful notes with a 69% win rate and superior helpfulness scores (3.87 vs. 3.36), demonstrating retrieval effectiveness that balanced the trade-off between scale and quality.
[99] How Should We Model the Probability of a Language?
Rasul Dent, Pedro Ortiz Suarez, Thibault Clérice, Benoît Sagot
Main category: cs.CL
TL;DR: This position paper argues that current language identification (LID) systems have limited coverage due to framing LID as decontextualized text classification, and proposes rethinking it as a routing problem with environmental cues.
Details
Motivation: Commercial LID systems only cover a few hundred of over 7,000 world languages, with research systems having patchy coverage. The paper argues this limited coverage is self-imposed due to problematic framing and institutional incentives.Method: Position paper analysis arguing for conceptual reframing: from decontextualized text classification to a routing problem that incorporates environmental cues and prior probability estimation.
Result: Identifies systemic issues in LID research and practice, proposing a paradigm shift toward context-aware, locally-plausible language identification.
Conclusion: Improving coverage for tail languages requires rethinking LID fundamentals - moving from global fixed-prior models to context-sensitive routing that leverages environmental information.
Abstract: Of the over 7,000 languages spoken in the world, commercial language identification (LID) systems only reliably identify a few hundred in written form. Research-grade systems extend this coverage under certain circumstances, but for most languages coverage remains patchy or nonexistent. This position paper argues that this situation is largely self-imposed. In particular, it arises from a persistent framing of LID as decontextualized text classification, which obscures the central role of prior probability estimation and is reinforced by institutional incentives that favor global, fixed-prior models. We argue that improving coverage for tail languages requires rethinking LID as a routing problem and developing principled ways to incorporate environmental cues that make languages locally plausible.
[100] Next Concept Prediction in Discrete Latent Space Leads to Stronger Language Models
Yuliang Liu, Yunchong Song, Yixuan Wang, Kewen Ge, Alex Lamb, Qipeng Guo, Kai Chen, Bowen Zhou, Zhouhan Lin
Main category: cs.CL
TL;DR: ConceptLM introduces Next Concept Prediction (NCP) as a generative pretraining paradigm that predicts discrete multi-token concepts rather than single tokens, creating a harder training objective that improves language model performance.
Details
Motivation: Traditional Next Token Prediction (NTP) in language modeling operates at the token level, which may be too granular. The authors propose that predicting higher-level concepts spanning multiple tokens could create a more challenging pretraining objective and lead to better language understanding.Method: ConceptLM uses Vector Quantization to quantize hidden states into discrete concepts, creating a concept vocabulary. The model is trained with both NCP and NTP objectives, where NCP predicts concepts that then guide subsequent token generation. Models are trained from scratch at various scales (70M to 1.5B parameters) using up to 300B training data.
Result: Experiments on 13 benchmarks show consistent performance gains over traditional token-level models. Continual pretraining on an 8B-parameter Llama model demonstrates that NCP can further improve models already trained with NTP.
Conclusion: NCP provides a promising path toward better language modeling by introducing a harder pretraining task that leads to more powerful language models through concept-level prediction.
Abstract: We propose Next Concept Prediction (NCP), a generative pretraining paradigm built on top of Next Token Prediction (NTP). NCP predicts discrete concepts that span multiple tokens, thereby forming a more challenging pretraining objective. Our model, ConceptLM, quantizes hidden states using Vector Quantization and constructs a concept vocabulary. It leverages both NCP and NTP to drive parameter updates and generates a concept to guide the generation of the following tokens. We train ConceptLM from scratch at scales ranging from 70M to 1.5B parameters with up to 300B training data, including Pythia and GPT-2 backbones. Results on 13 benchmarks show that NCP yields consistent performance gains over traditional token-level models. Furthermore, continual pretraining experiments on an 8B-parameter Llama model indicate that NCP can further improve an NTP-trained model. Our analysis suggests that NCP leads to more powerful language models by introducing a harder pretraining task, providing a promising path toward better language modeling.
[101] When Actions Go Off-Task: Detecting and Correcting Misaligned Actions in Computer-Use Agents
Yuting Ning, Jaylen Jones, Zhehao Zhang, Chentao Ye, Weitong Ruan, Junyi Li, Rahul Gupta, Huan Sun
Main category: cs.CL
TL;DR: DeAction: A guardrail system for detecting and correcting misaligned actions in computer-use agents before execution, with strong performance on the MisActBench benchmark.
Details
Motivation: Computer-use agents frequently produce misaligned actions that deviate from user intent due to external attacks (like indirect prompt injection) or internal limitations (like erroneous reasoning), creating safety risks and reducing task efficiency and reliability.Method: Proposes DeAction, a practical guardrail that detects misaligned actions before execution and iteratively corrects them through structured feedback. Also constructs MisActBench benchmark with human-annotated, action-level alignment labels covering three common real-world CUA deployment categories.
Result: DeAction outperforms all baselines: (1) On MisActBench, achieves over 15% absolute improvement in F1 score; (2) In online evaluation, reduces attack success rate by over 90% under adversarial settings while preserving or improving task success rate in benign environments, with moderate latency overhead.
Conclusion: This work provides the first systematic study of misaligned action detection in computer-use agents, offering both a comprehensive benchmark and an effective guardrail solution that significantly improves safety and reliability.
Abstract: Computer-use agents (CUAs) have made tremendous progress in the past year, yet they still frequently produce misaligned actions that deviate from the user’s original intent. Such misaligned actions may arise from external attacks (e.g., indirect prompt injection) or from internal limitations (e.g., erroneous reasoning). They not only expose CUAs to safety risks, but also degrade task efficiency and reliability. This work makes the first effort to define and study misaligned action detection in CUAs, with comprehensive coverage of both externally induced and internally arising misaligned actions. We further identify three common categories in real-world CUA deployment and construct MisActBench, a benchmark of realistic trajectories with human-annotated, action-level alignment labels. Moreover, we propose DeAction, a practical and universal guardrail that detects misaligned actions before execution and iteratively corrects them through structured feedback. DeAction outperforms all existing baselines across offline and online evaluations with moderate latency overhead: (1) On MisActBench, it outperforms baselines by over 15% absolute in F1 score; (2) In online evaluation, it reduces attack success rate by over 90% under adversarial settings while preserving or even improving task success rate in benign environments.
[102] YaRN: Efficient Context Window Extension of Large Language Models
Bowen Peng, Jeffrey Quesnelle, Honglu Fan, Enrico Shippole
Main category: cs.CL
TL;DR: YaRN is a compute-efficient method for extending the context window of transformer models using Rotary Position Embeddings (RoPE), requiring significantly less training data and steps than previous methods while enabling effective extrapolation beyond original training lengths.
Details
Motivation: Transformer models with Rotary Position Embeddings (RoPE) fail to generalize beyond their trained sequence lengths, limiting their practical utility for longer contexts. Previous methods for extending context windows require substantial computational resources and training data.Method: YaRN (Yet another RoPE extensioN method) is a compute-efficient approach that modifies the RoPE mechanism to enable context window extension. It requires 10x fewer tokens and 2.5x fewer training steps than previous methods while maintaining model performance.
Result: YaRN successfully extends LLaMA models’ context windows beyond their original pre-training limits, outperforming previous state-of-the-art methods. The method also demonstrates extrapolation capability beyond the fine-tuning dataset’s limited context.
Conclusion: YaRN provides an efficient solution for extending transformer models’ context windows, making long-context applications more practical while requiring significantly less computational resources than previous approaches.
Abstract: Rotary Position Embeddings (RoPE) have been shown to effectively encode positional information in transformer-based language models. However, these models fail to generalize past the sequence length they were trained on. We present YaRN (Yet another RoPE extensioN method), a compute-efficient method to extend the context window of such models, requiring 10x less tokens and 2.5x less training steps than previous methods. Using YaRN, we show that LLaMA models can effectively utilize and extrapolate to context lengths much longer than their original pre-training would allow, while also surpassing previous the state-of-the-art at context window extension. In addition, we demonstrate that YaRN exhibits the capability to extrapolate beyond the limited context of a fine-tuning dataset. Code is available at https://github.com/jquesnelle/yarn
[103] Automatic register identification for the open web using multilingual deep learning
Erik Henriksson, Amanda Myntti, Saara Hellström, Anni Eskelinen, Selcen Erten-Johansson, Veronika Laippala
Main category: cs.CL
TL;DR: Multilingual deep learning models for identifying web registers across 16 languages achieve 79% F1 score, with performance limited by inherent register ambiguity rather than model limitations.
Details
Motivation: To develop multilingual models that can identify web registers (text varieties like news reports, forums) across multiple languages, addressing the challenge of register classification at scale with complex taxonomies.Method: Created Multilingual CORE corpora with 72,000+ documents annotated with hierarchical taxonomy of 25 registers; used multi-label classification with deep learning models; compared multilingual vs. monolingual approaches; conducted data pruning and analysis of hybrid texts.
Result: Best model achieved 79% F1 averaged across 16 languages; performance ceiling observed across all models; data pruning increased performance to 90% F1; multilingual models outperformed monolingual ones, especially for low-resource languages; zero-shot performance dropped 3-8% on unseen languages.
Conclusion: Models can perform well with complex register schemes at multilingual scale, but performance is limited by inherent ambiguity in web registers rather than model limitations; multilingual approaches are beneficial, particularly for languages with limited training data.
Abstract: This article presents multilingual deep learning models for identifying web registers – text varieties such as news reports and discussion forums – across 16 languages. We introduce the Multilingual CORE corpora, which contain over 72,000 documents annotated with a hierarchical taxonomy of 25 registers designed to cover the entire open web. Using multi-label classification, our best model achieves 79% F1 averaged across languages, matching or exceeding previous studies that used simpler classification schemes. This demonstrates that models can perform well even with a complex register scheme at multilingual scale. However, we observe a consistent performance ceiling across all models and configurations. When we remove documents with uncertain labels through data pruning, performance increases to over 90% F1, suggesting that this ceiling stems from inherent ambiguity in web registers rather than model limitations. Analysis of hybrid texts (those combining multiple registers) reveals that the main challenge lies not in classifying hybrids themselves, but in distinguishing hybrid from non-hybrid documents. Multilingual models consistently outperform monolingual ones, particularly for languages with limited training data. Zero-shot performance on unseen languages drops by an average of 7%, though this varies by language (3–8%), indicating that while registers share features across languages, they also retain language-specific characteristics.
[104] Black Big Boxes: Tracing Adjective Order Preferences in Large Language Models
Jaap Jumelet, Lisa Bylinina, Willem Zuidema, Jakub Szymanik
Main category: cs.CL
TL;DR: Language models learn adjective ordering patterns primarily from training data frequencies but also generalize to unseen combinations and use contextual cues, showing they go beyond simple memorization.
Details
Motivation: To understand how language models acquire graded and context-sensitive word order preferences, specifically for adjective ordering in noun phrases, and to determine whether this can be explained by distributional learning alone or if models exhibit behavior beyond surface co-occurrence patterns.Method: Analyzed LM predictions using n-gram statistics to compare with training data frequencies, examined learning dynamics to study generalization to unseen adjective combinations, and used feature attribution methods to identify how LMs leverage contextual cues from sentence context.
Result: LM predictions are largely explained by training data frequencies (n-gram statistics account for much behavior), but models also generalize robustly to unseen adjective combinations and leverage contextual cues from sentence context, indicating behavior goes beyond simple memorization.
Conclusion: While distributional learning from training data frequencies explains much of LM adjective ordering behavior, models also demonstrate generalization capabilities and contextual sensitivity that go beyond surface co-occurrence patterns, suggesting more sophisticated linguistic learning.
Abstract: In English and other languages, multiple adjectives in noun phrases follow intricate ordering patterns. These patterns have been widely studied in linguistics and provide a useful test case for assessing how language models (LMs) acquire graded and context-sensitive word order preferences. We ask to what extent adjective order preferences in LMs can be explained by distributional learning alone, and where models exhibit behaviour that goes beyond surface co-occurrence patterns. We find that LM predictions are largely explained by training data frequencies: simple n-gram statistics account for much of their behaviour and closely mirror the preferences learned during training. However, by analysing learning dynamics we reveal that models also generalize robustly to unseen adjective combinations, indicating that their behaviour cannot be reduced to memorization of observed orders alone. Moreover, we show how LMs leverage word order cues from sentence context, demonstrating with feature attribution methods that contextual cues are an additional driver of adjective order in LM output.
[105] ComfyBench: Benchmarking LLM-based Agents in ComfyUI for Autonomously Designing Collaborative AI Systems
Xiangyuan Xue, Zeyu Lu, Di Huang, Zidong Wang, Wanli Ouyang, Lei Bai
Main category: cs.CL
TL;DR: LLM-based agents autonomously design collaborative AI systems using ComfyUI workflows, benchmarked by ComfyBench with 200 tasks, achieving comparable performance to o1-preview but limited on creative tasks.
Details
Motivation: Previous AI research focused on monolithic models for task performance, but this work explores using LLM-based agents to autonomously design collaborative AI systems, moving from single models to multi-agent collaborative systems.Method: Introduces ComfyBench benchmark with 200 diverse tasks and 3,205 annotated nodes across 20 workflows. Develops ComfyAgent framework with two core concepts: 1) representing workflows as code that can be reversibly converted and executed, and 2) constructing multi-agent systems that cooperate to learn from existing workflows and generate new ones.
Result: ComfyAgent achieves comparable resolve rate to o1-preview and significantly surpasses other agents on ComfyBench, but only resolves 15% of creative tasks, showing limitations in autonomous design of collaborative systems.
Conclusion: LLM-based agents still have significant room for improvement in autonomously designing collaborative AI systems, particularly for creative tasks. ComfyBench provides a foundation for developing more intelligent and autonomous collaborative AI systems.
Abstract: Much previous AI research has focused on developing monolithic models to maximize their intelligence, with the primary goal of enhancing performance on specific tasks. In contrast, this work attempts to study using LLM-based agents to design collaborative AI systems autonomously. To explore this problem, we first introduce ComfyBench to evaluate agents’s ability to design collaborative AI systems in ComfyUI. ComfyBench is a comprehensive benchmark comprising 200 diverse tasks covering various instruction-following generation challenges, along with detailed annotations for 3,205 nodes and 20 workflows. Based on ComfyBench, we further develop ComfyAgent, a novel framework that empowers LLM-based agents to autonomously design collaborative AI systems by generating workflows. ComfyAgent is based on two core concepts. First, it represents workflows with code, which can be reversibly converted into workflows and executed as collaborative systems by the interpreter. Second, it constructs a multi-agent system that cooperates to learn from existing workflows and generate new workflows for a given task. While experimental results demonstrate that ComfyAgent achieves a comparable resolve rate to o1-preview and significantly surpasses other agents on ComfyBench, ComfyAgent has resolved only 15% of creative tasks. LLM-based agents still have a long way to go in autonomously designing collaborative AI systems. Progress with ComfyBench is paving the way for more intelligent and autonomous collaborative AI systems.
[106] Building Multilingual Datasets for Predicting Mental Health Severity through LLMs: Prospects and Challenges
Konstantinos Skianis, John Pavlopoulos, A. Seza Doğruöz
Main category: cs.CL
TL;DR: Multilingual adaptation of mental health datasets for LLM evaluation across 6 languages reveals performance variability and risks in medical applications.
Details
Motivation: Address the research gap in LLM effectiveness for non-English mental health support applications by creating multilingual datasets for comprehensive evaluation.Method: Translate widely-used mental health datasets from English into six languages (Greek, Turkish, French, Portuguese, German, Finnish) and evaluate LLMs (GPT and Llama) on detecting mental health conditions and severity assessment across languages.
Result: Considerable variability in LLM performance across languages despite using the same translated dataset, highlighting language-specific nuances and mental health data coverage issues affecting accuracy.
Conclusion: LLMs show inconsistent performance in multilingual mental health support, with risks of misdiagnosis in medical settings; the approach offers cost savings for multilingual tasks but requires caution in clinical applications.
Abstract: Large Language Models (LLMs) are increasingly being integrated into various medical fields, including mental health support systems. However, there is a gap in research regarding the effectiveness of LLMs in non-English mental health support applications. To address this problem, we present a novel multilingual adaptation of widely-used mental health datasets, translated from English into six languages (e.g., Greek, Turkish, French, Portuguese, German, and Finnish). This dataset enables a comprehensive evaluation of LLM performance in detecting mental health conditions and assessing their severity across multiple languages. By experimenting with GPT and Llama, we observe considerable variability in performance across languages, despite being evaluated on the same translated dataset. This inconsistency underscores the complexities inherent in multilingual mental health support, where language-specific nuances and mental health data coverage can affect the accuracy of the models. Through comprehensive error analysis, we emphasize the risks of relying exclusively on LLMs in medical settings (e.g., their potential to contribute to misdiagnoses). Moreover, our proposed approach offers significant cost savings for multilingual tasks, presenting a major advantage for broad-scale implementation.
[107] RARe: Retrieval Augmented Retrieval with In-Context Examples
Atula Tejaswi, Yoonsang Lee, Sujay Sanghavi, Eunsol Choi
Main category: cs.CL
TL;DR: RARe enhances encoder-only retrieval models by incorporating semantically similar query-document pairs as in-context examples during finetuning, improving performance and out-of-domain generalization.
Details
Motivation: While in-context learning is well-established for decoder-only LLMs, its application to encoder-only models for text retrieval tasks remains underexplored. The paper investigates whether incorporating in-context examples (query-document pairs) can enhance retriever performance.Method: RARe finetunes pre-trained encoder-only models with in-context examples where the query is semantically similar to the target query. The approach analyzes design choices for in-context example augmentation for retrievers.
Result: RARe achieves performance gains of up to +2.72% nDCG across open-domain retrieval datasets (BeIR, RAR-b) compared to using only the target query. It exhibits stronger out-of-domain generalization similar to in-context learning in LLMs.
Conclusion: In-context learning can effectively enhance encoder-only retrieval models, with RARe demonstrating improved performance and generalization. The work lays foundation for future research on in-context learning for encoder models.
Abstract: While in-context learning is well-studied with decoder-only language models (LLMs), its utility for encoder-only models remains underexplored. We study in-context learning for encoder-only models for text retrieval tasks. Can incorporating in-context examples (query-document pairs) to the target query enhance retriever performance? Our approach, RARe, finetunes a pre-trained model with in-context examples whose query is semantically similar to the target query. This approach achieves performance gains of up to +2.72% nDCG across open-domain retrieval datasets (BeIR, RAR-b) compared to using the target query only as an input. In particular, we find RARe exhibits stronger out-of-domain generalization compared to models using queries without in-context examples, similar to what is seen for in-context learning in LLMs. We further provide analysis on the design choices of in-context example augmentation for retrievers and lay the foundation for future work.
[108] Automatic Item Generation for Personality Situational Judgment Tests with Large Language Models
Chang-Jin Li, Jiyuan Zhang, Yun Tang, Jian Li
Main category: cs.CL
TL;DR: LLM-based framework for automatically generating personality assessment tests (SJTs) using GPT-4 and ChatGPT-5, with validation across three studies showing psychometric soundness.
Details
Motivation: Traditional personality assessment development is labor-intensive and expert-dependent; LLMs offer potential for automated item generation but need structured frameworks for reliable personality SJT creation.Method: Three-study approach: Study 1 optimized prompt design and temperature settings on GPT-4; Study 2 tested cross-model generalizability on ChatGPT-5; Study 3 evaluated psychometric properties of generated SJTs across Big Five personality facets.
Result: Optimized prompts with temperature 1.0 worked best on GPT-4; approach generalized well to ChatGPT-5 with reproducible high-quality items; generated SJTs showed satisfactory reliability/validity across most Big Five facets, though some limitations in compliance facet and criterion-related validity.
Conclusion: LLM-based AIG approach can efficiently produce culturally appropriate and psychometrically sound personality SJTs, potentially surpassing traditional methods in efficiency while maintaining quality.
Abstract: Personality assessment through situational judgment tests (SJTs) offers unique advantages over traditional Likert-type self-report scales, yet their development remains labor-intensive, time-consuming, and heavily dependent on subject matter experts. Recent advances in large language models (LLMs) have shown promise for automatic item generation (AIG). Building on these developments, the present study focuses on developing and evaluating a structured and generalizable framework for automatically generating personality SJTs, using GPT-4 and ChatGPT-5 as empirical examples. Three studies were conducted. Study 1 systematically compared the effects of prompt design and temperature settings on the content validity of LLM-generated items to develop an effective and stable LLM-based AIG approach for personality SJT. Results showed that optimized prompts and a temperature of 1.0 achieved the best balance of creativity and accuracy on GPT-4. Study 2 examined the cross-model generalizability and reproducibility of this automated SJT generation approach through multiple rounds. The results showed that the approach consistently produced reproducible and high-quality items on ChatGPT-5. Study 3 evaluated the psychometric properties of LLM-generated SJTs covering five facets of the Big Five personality traits. Results demonstrated satisfactory reliability and validity across most facets, though limitations were observed in the convergent validity of the compliance facet and certain aspects of criterion-related validity. These findings provide robust evidence that the proposed LLM-based AIG approach can produce culturally appropriate and psychometrically sound SJTs with efficiency comparable to or exceeding traditional methods.
[109] Knowing When to Stop: Efficient Context Processing via Latent Sufficiency Signals
Roy Xie, Junlin Wang, Paul Rosu, Chunyuan Deng, Bolun Sun, Zihao Lin, Bhuwan Dhingra
Main category: cs.CL
TL;DR: Dynamic context cutoff enables LLMs to self-terminate processing when sufficient task-relevant information is acquired, using attention heads’ sufficiency signals for efficient processing.
Details
Motivation: Current LLMs process entire input contexts indiscriminately, which is inefficient when required information is localized. There's a need for methods that allow models to stop processing once they have enough information to answer queries.Method: Analyze model internals to discover attention heads that encode “sufficiency signals.” Use lightweight classifiers to detect when critical information has been processed, enabling models to self-terminate early. Larger models can use prompting for self-assessment.
Result: 3.4% accuracy improvement with 1.33x token reduction on average across six QA datasets. Superior performance compared to other context efficiency methods at equivalent token reduction rates. Emergent scaling: larger models show intrinsic self-assessment capabilities.
Conclusion: Models’ internal understanding naturally dictates processing needs rather than external compression heuristics. Dynamic context cutoff reveals a new efficiency paradigm for LLMs.
Abstract: Large language models (LLMs) process entire input contexts indiscriminately, which is inefficient when the information required to answer a query is localized within the context. We present dynamic context cutoff, a novel method enabling LLMs to self-terminate processing upon acquiring sufficient task-relevant information. Through analysis of model internals, we discover that specific attention heads inherently encode “sufficiency signals” – detectable through lightweight classifiers – that predict when critical information has been processed. This reveals a new efficiency paradigm: models’ internal understanding naturally dictates processing needs rather than external compression heuristics. Comprehensive experiments across six QA datasets (up to 40K tokens) with three model families (LLaMA/Qwen/Mistral, 1B-70B) demonstrate 3.4% accuracy improvement while achieving 1.33x token reduction on average. Furthermore, our method demonstrates superior performance compared to other context efficiency methods at equivalent token reduction rates. Additionally, we observe an emergent scaling phenomenon: while smaller models require probing for sufficiency detection, larger models exhibit intrinsic self-assessment capabilities through prompting.
[110] Summaries as Centroids for Interpretable and Scalable Text Clustering
Jairo Diaz-Rodriguez
Main category: cs.CL
TL;DR: k-NLPmeans and k-LLMmeans are text clustering methods that replace numeric centroids with textual summaries, offering human-readable clusters with optional LLM use for improved quality.
Details
Motivation: Traditional k-means clustering produces numeric centroids that are not human-interpretable for text data. There's a need for clustering methods that produce auditable, human-readable cluster prototypes while maintaining computational efficiency.Method: Two variants: k-NLPmeans uses lightweight deterministic summarizers for offline, low-cost operation; k-LLMmeans uses LLMs for summaries under fixed per-iteration budget. Both retain k-means assignments in embedding space but replace numeric centroids with textual summaries. Includes mini-batch extension for streaming text.
Result: Consistently outperforms classical baselines across diverse datasets and embedding models, approaching accuracy of recent LLM-based clustering without extensive LLM calls. Provides case study on sequential text streams and releases StackExchange-derived benchmark.
Conclusion: Summary-as-centroid approach enables human-readable, auditable text clustering with computational efficiency, offering LLM-optional solutions that balance interpretability and performance.
Abstract: We introduce k-NLPmeans and k-LLMmeans, text-clustering variants of k-means that periodically replace numeric centroids with textual summaries. The key idea, summary-as-centroid, retains k-means assignments in embedding space while producing human-readable, auditable cluster prototypes. The method is LLM-optional: k-NLPmeans uses lightweight, deterministic summarizers, enabling offline, low-cost, and stable operation; k-LLMmeans is a drop-in upgrade that uses an LLM for summaries under a fixed per-iteration budget whose cost does not grow with dataset size. We also present a mini-batch extension for real-time clustering of streaming text. Across diverse datasets, embedding models, and summarization strategies, our approach consistently outperforms classical baselines and approaches the accuracy of recent LLM-based clustering-without extensive LLM calls. Finally, we provide a case study on sequential text streams and release a StackExchange-derived benchmark for evaluating streaming text clustering.
[111] MET-Bench: Multimodal Entity Tracking for Evaluating the Limitations of Vision-Language and Reasoning Models
Vanya Cohen, Raymond Mooney
Main category: cs.CL
TL;DR: MET-Bench is a multimodal entity tracking benchmark that evaluates vision-language models’ ability to track entity states across text and images, revealing significant performance gaps between text-based and image-based tracking.
Details
Motivation: Entity state tracking is crucial for world modeling, but previous benchmarks only evaluated text-based tracking. The authors aim to assess how well vision-language models can track entity states when information comes from both text and images.Method: Created MET-Bench with two structured domains to evaluate multimodal entity tracking. Developed a reinforcement learning method to improve performance on the benchmark and applied it to open-source VLMs.
Result: Found significant performance gap between text-based and image-based entity tracking, with the discrepancy stemming from visual reasoning deficits rather than perception. Their RL method improved open-source VLMs to competitive performance with advanced closed models.
Conclusion: There’s a need for improved multimodal representations and reasoning techniques to bridge the gap between textual and visual entity tracking, especially for long-horizon multimodal tasks.
Abstract: Entity state tracking is a necessary component of world modeling that requires maintaining coherent representations of entities over time. Previous work has benchmarked entity tracking performance in purely text-based tasks. We introduce MET-Bench, a multimodal entity tracking benchmark designed to evaluate vision-language models’ ability to track entity states across modalities. Using two structured domains, we assess how effectively current models integrate textual and image-based state updates. Our findings reveal a significant performance gap between text-based and image-based entity tracking. We empirically show this discrepancy primarily stems from deficits in visual reasoning rather than perception. We further show that explicit text-based reasoning strategies improve performance, yet limitations remain in long-horizon multimodal tasks. We develop a reinforcement learning method to improve performance on MET-Bench. Applying our method to open-source VLMs achieves competitive performance with advanced closed models. Our results highlight the need for improved multimodal representations and reasoning techniques to bridge the gap between textual and visual entity tracking.
[112] SafeDialBench: A Fine-Grained Safety Evaluation Benchmark for Large Language Models in Multi-Turn Dialogues with Diverse Jailbreak Attacks
Hongye Cao, Sijia Jing, Yanming Wang, Ziyue Peng, Zhixin Bai, Zhe Cao, Meng Fang, Fan Feng, Boyan Wang, Jiaheng Liu, Tianpei Yang, Jing Huo, Yang Gao, Fanyu Meng, Xi Yang, Chao Deng, Junlan Feng
Main category: cs.CL
TL;DR: SafeDialBench: A fine-grained benchmark for evaluating LLM safety across multiple jailbreak attacks in multi-turn dialogues, with hierarchical safety taxonomy and comprehensive assessment framework.
Details
Motivation: Current LLM safety benchmarks focus on single-turn dialogues or single jailbreak methods, lacking detailed assessment of LLMs' capability to identify and handle unsafe information in multi-turn contexts.Method: Developed a two-tier hierarchical safety taxonomy with 6 dimensions, generated over 4000 multi-turn dialogues in Chinese/English across 22 scenarios, employed 7 jailbreak attack strategies, and created an assessment framework measuring detection, handling, and consistency capabilities.
Result: Evaluation of 17 LLMs shows Yi-34B-Chat and GLM4-9B-Chat have superior safety performance, while Llama3.1-8B-Instruct and o3-mini exhibit safety vulnerabilities.
Conclusion: SafeDialBench provides a comprehensive benchmark for assessing LLM safety in multi-turn dialogues against various jailbreak attacks, revealing significant performance differences among models.
Abstract: With the rapid advancement of Large Language Models (LLMs), the safety of LLMs has been a critical concern requiring precise assessment. Current benchmarks primarily concentrate on single-turn dialogues or a single jailbreak attack method to assess the safety. Additionally, these benchmarks have not taken into account the LLM’s capability of identifying and handling unsafe information in detail. To address these issues, we propose a fine-grained benchmark SafeDialBench for evaluating the safety of LLMs across various jailbreak attacks in multi-turn dialogues. Specifically, we design a two-tier hierarchical safety taxonomy that considers 6 safety dimensions and generates more than 4000 multi-turn dialogues in both Chinese and English under 22 dialogue scenarios. We employ 7 jailbreak attack strategies, such as reference attack and purpose reverse, to enhance the dataset quality for dialogue generation. Notably, we construct an innovative assessment framework of LLMs, measuring capabilities in detecting, and handling unsafe information and maintaining consistency when facing jailbreak attacks. Experimental results across 17 LLMs reveal that Yi-34B-Chat and GLM4-9B-Chat demonstrate superior safety performance, while Llama3.1-8B-Instruct and o3-mini exhibit safety vulnerabilities.
[113] ExpliCa: Evaluating Explicit Causal Reasoning in Large Language Models
Martina Miliani, Serena Auriemma, Alessandro Bondielli, Emmanuele Chersoni, Lucia Passaro, Irene Sucameli, Alessandro Lenci
Main category: cs.CL
TL;DR: ExpliCa dataset evaluates LLMs on explicit causal reasoning with temporal relations, showing models struggle with accuracy and confuse temporal with causal relations.
Details
Motivation: LLMs are increasingly used for interpretive tasks requiring causal reasoning accuracy, but current evaluation lacks datasets that integrate both causal and temporal relations with explicit linguistic markers.Method: Created ExpliCa dataset with causal and temporal relations in different linguistic orders, enriched with human acceptability ratings. Tested 7 LLMs using prompting and perplexity-based metrics.
Result: Even top models struggle to reach 0.80 accuracy. Models confuse temporal with causal relations, and performance is strongly influenced by linguistic order of events. Perplexity-based scores and prompting performance are differently affected by model size.
Conclusion: LLMs have significant limitations in explicit causal reasoning, particularly with temporal-causal distinctions and linguistic ordering effects, highlighting need for improved reasoning capabilities.
Abstract: Large Language Models (LLMs) are increasingly used in tasks requiring interpretive and inferential accuracy. In this paper, we introduce ExpliCa, a new dataset for evaluating LLMs in explicit causal reasoning. ExpliCa uniquely integrates both causal and temporal relations presented in different linguistic orders and explicitly expressed by linguistic connectives. The dataset is enriched with crowdsourced human acceptability ratings. We tested LLMs on ExpliCa through prompting and perplexity-based metrics. We assessed seven commercial and open-source LLMs, revealing that even top models struggle to reach 0.80 accuracy. Interestingly, models tend to confound temporal relations with causal ones, and their performance is also strongly influenced by the linguistic order of the events. Finally, perplexity-based scores and prompting performance are differently affected by model size.
[114] Taxation Perspectives from Large Language Models: A Case Study on Additional Tax Penalties
Eunkyung Choi, Youngjin Suh, Siun Lee, Hongseok Oh, Juheon Kang, Won Hur, Hun Park, Wonseok Hwang
Main category: cs.CL
TL;DR: PLAT is a new benchmark for evaluating LLMs’ ability to predict the legitimacy of additional tax penalties, featuring 300 questions derived from Korean court precedents across binary-choice, multiple-choice, and essay formats.
Details
Motivation: There's limited research on LLMs in taxation, with existing studies using simplified datasets that don't reflect real-world complexities, and most datasets aren't open-source, creating a gap for comprehensive tax law evaluation.Method: Created PLAT benchmark with 300 examples from 100 Korean court precedents, including binary-choice, multiple-choice, and essay-type questions to evaluate LLMs’ understanding of tax law and complex reasoning beyond simple statute application.
Result: Experiments show LLMs have limited baseline capabilities, especially in cases with conflicting issues requiring comprehensive understanding, and struggle with “AC” stages of “IRAC” even for advanced reasoning models like o3.
Conclusion: PLAT reveals significant limitations in current LLMs for tax law reasoning, highlighting the need for improved models that can handle complex legal reasoning and comprehensive case understanding.
Abstract: How capable are large language models (LLMs) in the domain of taxation? Although numerous studies have explored the legal domain, research dedicated to taxation remains scarce. Moreover, the datasets used in these studies are either simplified, failing to reflect the real-world complexities, or not released as open-source. To address this gap, we introduce PLAT, a new benchmark designed to assess the ability of LLMs to predict the legitimacy of additional tax penalties. PLAT comprises 300 examples: (1) 100 binary-choice questions, (2) 100 multiple-choice questions, and (3) 100 essay-type questions, all derived from 100 Korean court precedents. PLAT is constructed to evaluate not only LLMs’ understanding of tax law but also their performance in legal cases that require complex reasoning beyond straightforward application of statutes. Our systematic experiments with multiple LLMs reveal that (1) their baseline capabilities are limited, especially in cases involving conflicting issues that require a comprehensive understanding (not only of the statutes but also of the taxpayer’s circumstances), and (2) LLMs struggle particularly with the “AC” stages of “IRAC” even for advanced reasoning models like o3, which actively employ inference-time scaling. The dataset is publicly available at: https://huggingface.co/collections/sma1-rmarud/plat-predicting-the-legitimacy-of-punitive-additional-tax
[115] PlainQAFact: Retrieval-augmented Factual Consistency Evaluation Metric for Biomedical Plain Language Summarization
Zhiwen You, Yue Guo
Main category: cs.CL
TL;DR: PlainQAFact is a retrieval-augmented QA metric for evaluating factual consistency in biomedical plain language summarization, specifically addressing elaborative explanations that introduce external content.
Details
Motivation: Existing automatic factual consistency evaluation methods struggle with plain language summarization in medical domains due to elaborative explanations that add external content (definitions, background, examples) not present in source abstracts, creating challenges for lay audiences making health decisions.Method: PlainQAFact first classifies sentence types, then applies a retrieval-augmented QA scoring method. It’s trained on PlainFact, a fine-grained human-annotated dataset for evaluating factual consistency of both source-simplified and elaboratively explained sentences.
Result: PlainQAFact consistently outperforms existing evaluation metrics across all settings, especially for elaborative explanations. The paper analyzes its effectiveness across knowledge sources, answer extraction strategies, overlap measures, and document granularity levels.
Conclusion: The work presents a sentence-aware, retrieval-augmented metric targeted at elaborative explanations in biomedical PLS tasks, providing both a robust benchmark and practical tool for reliable plain language communication in medical domains.
Abstract: Hallucinated outputs from large language models (LLMs) pose risks in the medical domain, especially for lay audiences making health-related decisions. Existing automatic factual consistency evaluation methods, such as entailment- and question-answering (QA)- based, struggle with plain language summarization (PLS) due to elaborative explanation phenomenon, which introduces external content (e.g., definitions, background, examples) absent from the scientific abstract to enhance comprehension. To address this, we introduce PlainQAFact, an automatic factual consistency evaluation metric trained on a fine-grained, human-annotated dataset PlainFact, for evaluating factual consistency of both source-simplified and elaborately explained sentences. PlainQAFact first classifies sentence type, then applies a retrieval-augmented QA scoring method. Empirical results show that existing evaluation metrics fail to evaluate the factual consistency in PLS, especially for elaborative explanations, whereas PlainQAFact consistently outperforms them across all evaluation settings. We further analyze PlainQAFact’s effectiveness across external knowledge sources, answer extraction strategies, answer overlap measures, and document granularity levels, refining its overall factual consistency assessment. Taken together, our work presents a sentence-aware, retrieval-augmented metric targeted at elaborative explanations in biomedical PLS tasks, providing the community with both a robust benchmark and a practical tool to advance reliable and safe plain language communication in the medical domain. PlainQAFact and PlainFact are available at: https://github.com/zhiwenyou103/PlainQAFact
[116] From Token to Line: Enhancing Code Generation with a Long-Term Perspective
Tingwei Lu, Yangning Li, Liyuan Wang, Binghuai Lin, Qingsong Lv, Zishan Xu, Hai-Tao Zheng, Yinghui Li, Hong-Gee Kim
Main category: cs.CL
TL;DR: Proposes LSR-MCTS algorithm for code generation using line-by-line processing with Monte Carlo Tree Search and self-refinement to improve diversity and quality.
Details
Motivation: Current LLM-based code generation suffers from redundant outputs and overfitting to local patterns. Existing multi-token prediction approaches don't adequately address optimal processing length selection. Analysis shows attention spikes at line endings, suggesting lines as natural processing units.Method: LSR-MCTS algorithm that treats each code line as fundamental unit, uses Monte Carlo Tree Search to determine code line-by-line and select optimal path. Integrates self-refine mechanism at each node for diversity enhancement and error correction.
Result: Extensive experiments on three public coding benchmarks demonstrate method outperforms state-of-the-art performance approaches.
Conclusion: Line-by-line code generation with MCTS and self-refinement effectively addresses redundancy and local pattern overfitting, achieving superior performance on code generation benchmarks.
Abstract: The emergence of large language models (LLMs) has significantly promoted the development of code generation task, sparking a surge in pertinent literature. Current research is hindered by redundant generation results and a tendency to overfit local patterns in the short term. Although existing studies attempt to alleviate the issue by adopting a multi-token prediction strategy, there remains limited focus on choosing the appropriate processing length for generations. By analyzing the attention between tokens during the generation process of LLMs, it can be observed that the high spikes of the attention scores typically appear at the end of lines. This insight suggests that it is reasonable to treat each line of code as a fundamental processing unit and generate them sequentially. Inspired by this, we propose the LSR-MCTS algorithm, which leverages MCTS to determine the code line-by-line and select the optimal path. Further, we integrate a self-refine mechanism at each node to enhance diversity and generate higher-quality programs through error correction. Extensive experiments and comprehensive analyses on three public coding benchmarks demonstrate that our method outperforms the state-of-the-art performance approaches.
[117] Integrating Structural and Semantic Signals in Text-Attributed Graphs with BiGTex
Azadeh Beiranvand, Seyed Mehdi Vahidipour
Main category: cs.CL
TL;DR: BiGTex is a novel architecture that integrates GNNs and LLMs through bidirectional Graph-Text Fusion Units for text-attributed graph representation learning.
Details
Motivation: Text-attributed graphs (TAGs) require models to capture both semantic richness of node-associated texts and structural dependencies of the graph. GNNs excel at modeling topological information but lack text processing capabilities, while LLMs are proficient in text understanding but unaware of graph structure.Method: Proposes BiGTex with stacked Graph-Text Fusion Units that enable mutual attention between textual and structural representations, allowing bidirectional information flow. Uses parameter-efficient fine-tuning (LoRA) with frozen LLM weights while adapting to task-specific signals.
Result: Extensive experiments on five benchmark datasets demonstrate state-of-the-art performance in node classification and effective generalization to link prediction. Ablation study highlights importance of soft prompting and bi-directional attention.
Conclusion: BiGTex successfully integrates GNNs and LLMs for text-attributed graph representation learning, achieving strong performance through bidirectional fusion of textual and structural information.
Abstract: Text-attributed graphs (TAGs) present unique challenges in representation learning by requiring models to capture both the semantic richness of node-associated texts and the structural dependencies of the graph. While graph neural networks (GNNs) excel at modeling topological information, they lack the capacity to process unstructured text. Conversely, large language models (LLMs) are proficient in text understanding but are typically unaware of graph structure. In this work, we propose BiGTex (Bidirectional Graph Text), a novel architecture that tightly integrates GNNs and LLMs through stacked Graph-Text Fusion Units. Each unit allows for mutual attention between textual and structural representations, enabling information to flow in both directions, text influencing structure and structure guiding textual interpretation. The proposed architecture is trained using parameter-efficient fine-tuning (LoRA), keeping the LLM frozen while adapting to task-specific signals. Extensive experiments on five benchmark datasets demonstrate that BiGTex achieves state-of-the-art performance in node classification and generalizes effectively to link prediction. An ablation study further highlights the importance of soft prompting and bi-directional attention in the model’s success.
[118] GMSA: Enhancing Context Compression via Group Merging and Layer Semantic Alignment
Jiwei Tang, Zhicheng Zhang, Shunlong Wu, Jingheng Ye, Lichen Bai, Zitai Wang, Tingwei Lu, Lin Hai, Yiming Zhao, Hai-Tao Zheng, Hong-Gee Kim
Main category: cs.CL
TL;DR: GMSA is an encoder-decoder context compression framework that generates compact soft token sequences to address computational cost and redundancy in long-context LLMs.
Details
Motivation: Large Language Models face high computational costs and information redundancy in long-context scenarios, requiring efficient compression methods to maintain performance while reducing resource usage.Method: Proposes GMSA with Group Merging for uniform aggregation to mitigate semantic dominance during autoencoder pretraining, and Layer Semantic Alignment to bridge semantic gaps between high-level abstract and low-level input semantics. Uses autoencoder pretraining followed by downstream task fine-tuning.
Result: GMSA improves context reconstruction compared to existing soft prompt compression methods and outperforms baselines on multiple long-context QA and summarization benchmarks across two backbone models while maintaining low latency.
Conclusion: GMSA effectively addresses computational and redundancy challenges in long-context LLMs through innovative compression techniques, demonstrating practical improvements in both performance and efficiency.
Abstract: Large Language Models (LLMs) have achieved remarkable performance across a wide range of Natural Language Processing (NLP) tasks. However, in long-context scenarios, they face two challenges: high computational cost and information redundancy. To address these challenges, we propose GMSA, an encoder-decoder context compression framework that generates a compact sequence of soft tokens for downstream tasks. GMSA introduces Group Merging to achieve more uniform aggregation, mitigating semantic dominance during autoencoder pretraining, and Layer Semantic Alignment (LSA) to bridge the semantic gap between high-level abstract semantics and low-level input semantics. We first pretrain GMSA as an autoencoder and then fine-tune it for downstream tasks. Experiments demonstrate that GMSA improves context reconstruction compared to existing soft prompt compression paradigm and outperforms baselines on multiple long-context question answering and summarization benchmarks across two backbone models, while maintaining low end-to-end latency.
[119] ABBA-Adapters: Efficient and Expressive Fine-Tuning of Foundation Models
Raghav Singhal, Kaustubh Ponkshe, Rohit Vartak, Praneeth Vepakomma
Main category: cs.CL
TL;DR: ABBA is a new Parameter-Efficient Fine-Tuning method that uses a Hadamard product of two independent low-rank matrices, decoupling updates from pre-trained weights for higher expressivity and better performance on reasoning tasks.
Details
Motivation: Current PEFT methods like LoRA have limited expressivity due to low-rank constraints, and recent approaches like HiRA still rely on pre-trained model structure. There's a need for more expressive PEFT methods that can better adapt LLMs to new domains while maintaining parameter efficiency.Method: ABBA reparameterizes weight updates as a Hadamard product of two independently learnable low-rank matrices, fully decoupling the update from pre-trained weights. This allows both components to be optimized freely, increasing expressivity under the same parameter budget.
Result: ABBA achieves state-of-the-art results on arithmetic and commonsense reasoning benchmarks, consistently outperforming existing PEFT methods by a significant margin across multiple models. Matrix reconstruction experiments validate its higher expressivity.
Conclusion: ABBA represents a significant advancement in PEFT methods by decoupling updates from pre-trained weights, enabling higher expressivity and better adaptation of LLMs to new domains while maintaining parameter efficiency.
Abstract: Large Language Models have demonstrated strong performance across a wide range of tasks, but adapting them efficiently to new domains remains a key challenge. Parameter-Efficient Fine-Tuning (PEFT) methods address this by introducing lightweight, trainable modules while keeping most pre-trained weights fixed. The prevailing approach, LoRA, models updates using a low-rank decomposition, but its expressivity is inherently constrained by the rank. Recent methods like HiRA aim to increase expressivity by incorporating a Hadamard product with the frozen weights, but still rely on the structure of the pre-trained model. We introduce ABBA, a new PEFT architecture that reparameterizes the update as a Hadamard product of two independently learnable low-rank matrices. In contrast to prior work, ABBA fully decouples the update from the pre-trained weights, enabling both components to be optimized freely. This leads to significantly higher expressivity under the same parameter budget, a property we validate through matrix reconstruction experiments. Empirically, ABBA achieves state-of-the-art results on arithmetic and commonsense reasoning benchmarks, consistently outperforming existing PEFT methods by a significant margin across multiple models. Our code is publicly available at: https://github.com/CERT-Lab/abba.
[120] FAID: Fine-Grained AI-Generated Text Detection Using Multi-Task Auxiliary and Multi-Level Contrastive Learning
Minh Ngoc Ta, Dong Cao Van, Duc-Anh Hoang, Minh Le-Anh, Truong Nguyen, My Anh Tran Nguyen, Yuxia Wang, Preslav Nakov, Sang Dinh
Main category: cs.CL
TL;DR: FAID introduces a fine-grained detection framework to classify text as human-written, LLM-generated, or human-LLM collaborative, while also identifying the underlying LLM family, using multi-level contrastive learning and multi-task classification.
Details
Motivation: The increasing collaboration between humans and AI models in generative tasks creates challenges in distinguishing between human-written, LLM-generated, and human-LLM collaborative texts, necessitating better detection methods for transparency and accountability.Method: FAID uses multi-level contrastive learning with multi-task auxiliary classification to capture subtle stylistic cues, modeling LLM families as distinct stylistic entities with adaptation mechanisms for distributional shifts without retraining.
Result: FAID outperforms several baselines, particularly enhancing generalization accuracy on unseen domains and new LLMs, demonstrating effectiveness in fine-grained text classification.
Conclusion: FAID offers a potential solution for improving transparency and accountability in AI-assisted writing through fine-grained detection of authorship and model characteristics.
Abstract: The growing collaboration between humans and AI models in generative tasks has introduced new challenges in distinguishing between human-written, LLM-generated, and human-LLM collaborative texts. In this work, we collect a multilingual, multi-domain, multi-generator dataset FAIDSet. We further introduce a fine-grained detection framework FAID to classify text into these three categories, and also to identify the underlying LLM family of the generator. Unlike existing binary classifiers, FAID is built to capture both authorship and model-specific characteristics. Our method combines multi-level contrastive learning with multi-task auxiliary classification to learn subtle stylistic cues. By modeling LLM families as distinct stylistic entities, we incorporate an adaptation to address distributional shifts without retraining for unseen data. Our experimental results demonstrate that FAID outperforms several baselines, particularly enhancing the generalization accuracy on unseen domains and new LLMs, thus offering a potential solution for improving transparency and accountability in AI-assisted writing. Our data and code are available at https://github.com/mbzuai-nlp/FAID
[121] PBEBench: A Multi-Step Programming by Examples Reasoning Benchmark inspired by Historical Linguistics
Atharva Naik, Prakam, Yash Mathur, Darsh Agrawal, Manav Kapadnis, Yuwei An, Clayton Marr, Carolyn Rose, David Mortensen
Main category: cs.CL
TL;DR: A novel benchmark for evaluating inductive reasoning in LLMs using Programming by Examples (PBE) tasks inspired by historical linguistics forward reconstruction, with automated generation of string rewrite program cascades.
Details
Motivation: Current benchmarks evaluate LLM reasoning within specific domains (math, coding, etc.) but few examine reasoning as a general capability. The paper aims to create domain-agnostic benchmarks for inductive reasoning inspired by historical linguistics tasks.Method: Develops a fully automated pipeline to generate Programming by Examples (PBE) problems involving string rewrite program cascades. Creates two benchmarks: PBEBench-Lite for efficient model stratification and PBEBench with complexity similar to historical linguistics tasks.
Result: Shows substantial performance gap between models using test-time compute/Long Chain-of-Thought vs. those without. Recent models drop below 5% solve rate for hard instances (cascade lengths 20-30), falling short of historical linguistics requirements even with advanced scaling techniques.
Conclusion: The benchmarks effectively evaluate inductive reasoning capabilities, revealing current LLMs’ limitations in complex reasoning tasks despite advances. The approach enables scalable, contamination-free evaluation of reasoning models.
Abstract: Although many benchmarks evaluate the reasoning abilities of Large Language Models (LLMs) within domains such as mathematics, coding, or data wrangling, few abstract away from domain specifics to examine reasoning as a capability in and of itself. We contribute a novel type of benchmark evaluating the inductive reasoning capabilities of LLMs that is inspired by the forward reconstruction task from historical linguistics but is formulated in an extremely simple, general way (in the form of Programming by Examples). The task involves generating a cascade of simple string rewrite programs to transform a given list of input strings into a list of desired output strings. We present a fully automated pipeline that programmatically generates problems of this type with controllable difficulty, enabling scalable evaluation of reasoning models while avoiding contamination. Using this approach, we construct two benchmarks: PBEBench-Lite, which efficiently stratifies models of varying capabilities, and PBEBench, which requires models to induce programs similar in complexity to those constructed by historical linguists. Our experiments reveal a substantial performance gap between models that leverage test-time compute or LCoT (long chain-of-thought) reasoning and those that do not. Moreover, although recent models show promise, the solve rate for both of them drops below 5% for hard instances of the PBEBench dataset (ground truth cascade lengths of 20 and 30, respectively), falling well short of realistic historical linguistics requirements even with computationally expensive, popular scaling techniques from the PBE and reasoning literature. Additionally, we also study the effectiveness of different scaling strategies and the impact of various hyperparameters on the difficulty of the generated data using gpt-oss-120b, the best-performing open-source model.
[122] ChatCFD: An LLM-Driven Agent for End-to-End CFD Automation with Structured Knowledge and Reasoning
E Fan, Kang Hu, Zhuowen Wu, Jiangyang Ge, Jiawei Miao, Yuzhi Zhang, He Sun, Weizong Wang, Tianhan Zhang
Main category: cs.CL
TL;DR: ChatCFD is an LLM-driven multi-agent system for automating end-to-end CFD workflows using OpenFOAM, achieving high execution success and physical fidelity through structured knowledge bases and error correction mechanisms.
Details
Motivation: CFD is crucial for scientific advancement but faces operational complexity and high expertise barriers. Current methods have low automation success rates, requiring specialized knowledge that limits accessibility and efficiency.Method: Multi-agent LLM system powered by DeepSeek-R1/V3 with structured domain knowledge bases, precise error locator, iterative reflection, and dedicated Physics Interpreter. Uses modular, MCP-compatible design for collaborative AI-driven CFD.
Result: Achieved 82.1% execution success on 315 benchmark cases (vs. 6.2% for MetaOpenFOAM, 42.3% for Foam-Agent), 68.12% physical fidelity, 97.4% summary fidelity, and efficient resource usage (192.1k tokens, $0.208 per case).
Conclusion: ChatCFD dramatically outperforms existing methods, enabling scalable, collaborative AI-driven CFD automation with high success rates and physical fidelity while maintaining resource efficiency.
Abstract: Computational Fluid Dynamics (CFD) is critical for scientific advancement but is hindered by operational complexity and high expertise barriers. This paper introduces ChatCFD, a Large Language Model (LLM)-driven multi-agent system designed for end-to-end CFD automation using OpenFOAM. Powered by DeepSeek-R1/V3, ChatCFD integrates structured domain knowledge bases, a precise error locator, and iterative reflection to dramatically outperform existing methods. On 315 benchmark cases, ChatCFD achieves 82.1% execution success (vs. 6.2% for MetaOpenFOAM and 42.3% for Foam-Agent) and 68.12% physical fidelity - a novel metric assessing scientific meaningfulness beyond mere runnability. A dedicated Physics Interpreter attains 97.4% summary fidelity, bridging the gap between narrative fluency and the enforcement of tight physical constraints. Resource analysis confirms efficiency, averaging 192.1k tokens and $0.208 per case, significantly lower than baseline costs. Ablation studies identify the Error Locator and Solver Template DB as critical, with the latter’s removal collapsing accuracy to 48%. The system exhibits robust flexibility, achieving 95.23% success in autonomous solver selection and 100% in turbulence modeling, while successfully reproducing complex literature cases (e.g., NACA0012, supersonic nozzle) with 60-80% success rates where baselines failed. Featuring a modular, MCP-compatible design, ChatCFD facilitates scalable, collaborative AI-driven CFD. Code is available at: https://github.com/ConMoo/ChatCFD
[123] Beyond Bias Scores: Unmasking Vacuous Neutrality in Small Language Models
Sumanth Manduru, Carlotta Domeniconi
Main category: cs.CL
TL;DR: VaNeu framework evaluates fairness in Small Language Models (0.5-5B parameters) across four stages: biases, utility, ambiguity handling, and positional bias, revealing hidden vulnerabilities despite initial low bias scores.
Details
Motivation: The rapid adoption of Small Language Models for resource-constrained applications has outpaced understanding of their ethical and fairness implications, creating a need for comprehensive evaluation frameworks before deployment.Method: Introduced Vacuous Neutrality Framework (VaNeu) - a multi-dimensional evaluation paradigm examining model robustness across four stages: biases, utility, ambiguity handling, and positional bias over diverse social bias categories. Conducted first large-scale audit of 9 SLMs (0.5-5B parameters) from four model families under both ambiguous and disambiguated contexts.
Result: Models demonstrating low bias in early stages often fail subsequent evaluations, revealing hidden vulnerabilities and unreliable reasoning. The framework exposes limitations in current SLM fairness assessments.
Conclusion: There’s a need for more comprehensive understanding of fairness and reliability in SLMs, and the VaNeu framework serves as a principled tool for responsible deployment in socially sensitive settings.
Abstract: The rapid adoption of Small Language Models (SLMs) for resource constrained applications has outpaced our understanding of their ethical and fairness implications. To address this gap, we introduce the Vacuous Neutrality Framework (VaNeu), a multi-dimensional evaluation paradigm designed to assess SLM fairness prior to deployment. The framework examines model robustness across four stages - biases, utility, ambiguity handling, and positional bias over diverse social bias categories. To the best of our knowledge, this work presents the first large-scale audit of SLMs in the 0.5-5B parameter range, an overlooked “middle tier” between BERT-class encoders and flagship LLMs. We evaluate nine widely used SLMs spanning four model families under both ambiguous and disambiguated contexts. Our findings show that models demonstrating low bias in early stages often fail subsequent evaluations, revealing hidden vulnerabilities and unreliable reasoning. These results underscore the need for a more comprehensive understanding of fairness and reliability in SLMs, and position the proposed framework as a principled tool for responsible deployment in socially sensitive settings.
[124] Curriculum-Guided Layer Scaling for Language Model Pretraining
Karanpartap Singh, Neil Band, Ehsan Adeli
Main category: cs.CL
TL;DR: Curriculum-Guided Layer Scaling (CGLS) synchronizes increasing data difficulty with model growth through progressive layer stacking during pretraining, improving efficiency and performance on knowledge-intensive tasks.
Details
Motivation: Motivated by cognitive development where humans gradually build knowledge as their brains mature, the authors aim to improve compute-efficient pretraining by aligning model growth with increasing data complexity.Method: CGLS framework gradually adds layers during training while simultaneously increasing data difficulty through curriculum learning - starting with simpler synthetic data and progressing to more complex, specialized content.
Result: At 100M parameter scale with synthetic-to-web data curriculum, CGLS outperforms baselines on PIQA and ARC benchmarks. At 1.2B scale with DataComp-LM corpus stratified by technicality, it shows better generalization and zero-shot performance on various downstream tasks.
Conclusion: CGLS unlocks the potential of progressive stacking, offering a simple yet effective strategy for improving generalization on knowledge-intensive and reasoning tasks through synchronized model growth and data difficulty progression.
Abstract: As the cost of pretraining large language models grows, there is continued interest in strategies to improve learning efficiency during this core training stage. Motivated by cognitive development, where humans gradually build knowledge as their brains mature, we propose Curriculum-Guided Layer Scaling (CGLS), a framework for compute-efficient pretraining that synchronizes increasing data difficulty with model growth through progressive layer stacking (i.e. gradually adding layers during training). At the 100M parameter scale, using a curriculum transitioning from synthetic short stories to general web data, CGLS outperforms baseline methods on the question-answering benchmarks PIQA and ARC. Pretraining at the 1.2B scale, we stratify the DataComp-LM corpus with a DistilBERT-based classifier and progress from general text to highly technical or specialized content. Our results show that progressively increasing model depth alongside sample difficulty leads to better generalization and zero-shot performance on various downstream benchmarks. Altogether, our findings demonstrate that CGLS unlocks the potential of progressive stacking, offering a simple yet effective strategy for improving generalization on knowledge-intensive and reasoning tasks.
[125] Language Bottleneck Models for Qualitative Knowledge State Modeling
Antonin Berthon, Mihaela van der Schaar
Main category: cs.CL
TL;DR: LBMs use LLMs to create interpretable textual summaries of student knowledge states for cognitive diagnosis and knowledge tracing, offering nuanced insights beyond traditional quantitative models while maintaining competitive accuracy.
Details
Motivation: Existing cognitive diagnosis and knowledge tracing methods either provide limited expressivity (quantitative concept mastery estimates) or prioritize predictive accuracy over interpretability. There's a need for models that can capture nuanced insights like misconceptions while remaining interpretable.Method: Language Bottleneck Models (LBMs) use an encoder LLM to produce textual knowledge state summaries, which a decoder LLM then uses to predict future student performance. The models can be fine-tuned with reinforcement learning (encoder) and supervised fine-tuning (decoder) to improve summary quality and predictive performance.
Result: LBMs reveal qualitative insights beyond what traditional CD and KT models can capture, achieve competitive accuracy with improved sample efficiency, and demonstrate that fine-tuning improves both summary quality and predictive performance.
Conclusion: LBMs offer a promising approach to student knowledge assessment that combines interpretability with competitive predictive performance, enabling capture of nuanced insights like misconceptions that traditional quantitative models cannot express.
Abstract: Accurately assessing student knowledge is central to education. Cognitive Diagnosis (CD) models estimate student proficiency at a fixed point in time, while Knowledge Tracing (KT) methods model evolving knowledge states to predict future performance. However, existing approaches either provide quantitative concept mastery estimates with limited expressivity (CD, probabilistic KT) or prioritize predictive accuracy at the cost of interpretability (deep learning KT). We propose Language Bottleneck Models (LBMs), where an encoder LLM produces textual knowledge state summaries, which a decoder LLM uses to predict future performance. This produces interpretable summaries that can express nuanced insights–such as misconceptions–that CD and KT models cannot capture. Extensive validation across synthetic and real-world datasets shows LBMs reveal qualitative insights beyond what CD and KT models can capture, while achieving competitive accuracy with improved sample efficiency. We demonstrate that the encoder and decoder can be fine-tuned with reinforcement learning and supervised fine-tuning respectively to improve both summary quality and predictive performance.
[126] AutoMixer: Checkpoint Artifacts as Automatic Data Mixers
Ernie Chang, Yang Li, Patrick Huber, Vish Vogeti, David Kant, Yangyang Shi, Vikas Chandra
Main category: cs.CL
TL;DR: A framework that uses checkpoint models from training trajectories to optimize data mixtures for language model capabilities, leveraging first-order influence approximation to identify beneficial training data.
Details
Motivation: Current language model training lacks clear methods to determine optimal data mixtures for desired capabilities, as the relationship between data and tasks is difficult to model. Checkpoint models saved during training are underutilized resources that contain valuable signals about emerging capabilities.Method: Identify checkpoint models with specific capabilities on benchmarks, then use their aggregated first-order influence approximation over source data to determine optimal data mixtures. The framework leverages training artifacts to enhance data quality.
Result: Demonstrated on eight reasoning benchmarks with significant improvements in pretraining setting, achieving performance improvements of up to 1.93%. Shows checkpoint models can effectively enhance data quality and optimize mixtures.
Conclusion: Checkpoint models from training trajectories are valuable resources for optimizing data mixtures, providing a practical approach to enhance language model capabilities through better data selection.
Abstract: In language model training, it is desirable to equip models with capabilities from various tasks. However, it is not clear how to directly obtain the right data mixtures for these capabilities as the relationship between data and tasks is difficult to be modeled. In this work, we observe that checkpoint models exhibit emerging capabilities at different points in the training trajectory. Often, the training process saves checkpoints as artifacts that are under-utilized as a source of in-training data signals. We identify these artifact models based on their respective capabilities on the benchmarks and leverage them as data mixers by using their aggregated first-order influence approximation over source data. We demonstrated on eight reasoning benchmarks that the proposed framework shows significant improvements in the pretraining setting, with performance improvements of up to 1.93%. Overall, this shows the potential of checkpoint models to enhance data quality and optimize data mixtures.
[127] MedVAL: Toward Expert-Level Medical Text Validation with Language Models
Asad Aali, Vasiliki Bikia, Maya Varma, Nicole Chiou, Sophie Ostmeier, Arnav Singhvi, Magdalini Paschali, Ashwin Kumar, Andrew Johnston, Karimar Amador-Martinez, Eduardo Juan Perez Guerrero, Paola Naovi Cruz Rivera, Sergios Gatidis, Christian Bluethgen, Eduardo Pontes Reis, Eddy D. Zandee van Rilland, Poonam Laxmappa Hosamani, Kevin R Keet, Minjoung Go, Evelyn Ling, David B. Larson, Curtis Langlotz, Roxana Daneshjou, Jason Hom, Sanmi Koyejo, Emily Alsentzer, Akshay S. Chaudhari
Main category: cs.CL
TL;DR: MedVAL: A self-supervised distillation method that trains evaluator LMs to detect factual errors in LM-generated medical text without requiring physician labels or reference outputs, achieving performance approaching human expert level.
Details
Motivation: Current evaluation of LM-generated medical text relies on costly manual physician review, and expert-composed reference outputs are often unavailable in real-world settings. While LLM-as-a-judge offers scalability, even frontier LMs miss subtle but clinically significant errors.Method: Proposes MedVAL, a novel self-supervised distillation method that leverages synthetic data to train evaluator LMs to assess factual consistency between LM-generated medical outputs and inputs. Introduces MedVAL-Bench dataset of 840 physician-annotated outputs across 6 diverse medical tasks.
Result: MedVAL significantly improves alignment with physicians across seen and unseen tasks, increasing average F1 scores from 66% to 83%. Improves best-performing proprietary LM (GPT-4o) by 8% without training on physician-labeled data, achieving performance statistically non-inferior to a single human expert.
Conclusion: MedVAL enables scalable, risk-aware evaluation of LM-generated medical text, approaching expert-level ability in validation. The method and benchmark support clinical integration of language models in medical applications.
Abstract: With the growing use of language models (LMs) in clinical environments, there is an immediate need to evaluate the accuracy and safety of LM-generated medical text. Currently, such evaluation relies solely on manual physician review. However, detecting errors in LM-generated text is challenging because 1) manual review is costly and 2) expert-composed reference outputs are often unavailable in real-world settings. While the “LLM-as-a-judge” paradigm offers scalable evaluation, even frontier LMs can miss subtle but clinically significant errors. We propose MedVAL, a novel, self-supervised, data-efficient distillation method that leverages synthetic data to train evaluator LMs to assess whether LM-generated medical outputs are factually consistent with inputs, without requiring physician labels or reference outputs. To evaluate LM performance, we introduce MedVAL-Bench, a dataset of 840 physician-annotated outputs across 6 diverse medical tasks capturing real-world challenges. Across 10 state-of-the-art LMs spanning open-source and proprietary models, MedVAL distillation significantly improves (p < 0.001) alignment with physicians across seen and unseen tasks, increasing average F1 scores from 66% to 83%. Despite strong baseline performance, MedVAL improves the best-performing proprietary LM (GPT-4o) by 8% without training on physician-labeled data, demonstrating a performance statistically non-inferior to a single human expert on a subset annotated by multiple physicians (p < 0.001). To support a scalable, risk-aware pathway towards clinical integration, we open-source: 1) Codebase (https://github.com/StanfordMIMI/MedVAL), 2) MedVAL-Bench (https://huggingface.co/datasets/stanfordmimi/MedVAL-Bench), 3) MedVAL-4B (https://huggingface.co/stanfordmimi/MedVAL-4B). Our benchmark provides evidence of LMs approaching expert-level ability in validating AI-generated medical text.
[128] DRAGOn: Designing RAG On Periodically Updated Corpus
Fedor Chernogorskii, Sergei Averkiev, Liliya Kudraleeva, Zaven Martirosian, Maria Tikhonova, Valentin Malykh, Alena Fenogenova
Main category: cs.CL
TL;DR: DRAGOn is a method for creating RAG benchmarks on regularly updated corpora, featuring reference datasets, question generation, automatic evaluation, and public leaderboards.
Details
Motivation: Current RAG benchmarks suffer from data leakage and lack regular updates, making it hard to fairly compare systems on unseen data. There's a need for standardized evaluation on dynamic corpora.Method: Extracts Knowledge Graph from text corpus, uses LLMs to generate question-answer pairs, creates regularly updated datasets to prevent data leakage, and provides LLM-as-Judge metrics for comprehensive evaluation.
Result: Demonstrated methodology using Russian news outlets, launched public leaderboard to track RAG system development and encourage community participation.
Conclusion: DRAGOn provides a robust framework for evaluating RAG systems on dynamic corpora, addressing data leakage issues and enabling fair comparison through regularly updated benchmarks.
Abstract: This paper introduces DRAGOn, method to design a RAG benchmark on a regularly updated corpus. It features recent reference datasets, a question generation framework, an automatic evaluation pipeline, and a public leaderboard. Specified reference datasets allow for uniform comparison of RAG systems, while newly generated dataset versions mitigate data leakage and ensure that all models are evaluated on unseen, comparable data. The pipeline for automatic question generation extracts the Knowledge Graph from the text corpus and produces multiple question-answer pairs utilizing modern LLM capabilities. A set of diverse LLM-as-Judge metrics is provided for a comprehensive model evaluation. We used Russian news outlets to form the datasets and demonstrate our methodology. We launch a public leaderboard to track the development of RAG systems and encourage community participation.
[129] Efficient Attention Mechanisms for Large Language Models: A Survey
Yutao Sun, Zhenyu Li, Yike Zhang, Tengyu Pan, Bowen Dong, Yuyi Guo, Jianyong Wang
Main category: cs.CL
TL;DR: Survey paper on efficient attention mechanisms for transformers, covering linear attention (kernel approximations, recurrent formulations) and sparse attention (fixed patterns, block-wise routing, clustering) to address quadratic complexity limitations.
Details
Motivation: The quadratic time and memory complexity of self-attention in transformers is a fundamental obstacle to efficient long-context modeling, limiting scalability and practical deployment of large language models.Method: Systematic survey of two principal categories: 1) Linear attention methods achieving linear complexity through kernel approximations, recurrent formulations, or fastweight dynamics; 2) Sparse attention techniques limiting computation to selected token subsets using fixed patterns, block-wise routing, or clustering strategies.
Result: Comprehensive overview integrating algorithmic innovations and hardware-level considerations, analyzing incorporation of efficient attention into large-scale pre-trained language models, including both pure efficient attention architectures and hybrid designs.
Conclusion: This survey serves as a foundational reference for advancing scalable and efficient language model design by aligning theoretical foundations with practical deployment strategies for long-context modeling.
Abstract: Transformer-based architectures have become the prevailing backbone of large language models. However, the quadratic time and memory complexity of self-attention remains a fundamental obstacle to efficient long-context modeling. To address this limitation, recent research has introduced two principal categories of efficient attention mechanisms. Linear attention methods achieve linear complexity through kernel approximations, recurrent formulations, or fastweight dynamics, thereby enabling scalable inference with reduced computational overhead. Sparse attention techniques, in contrast, limit attention computation to selected subsets of tokens based on fixed patterns, block-wise routing, or clustering strategies, enhancing efficiency while preserving contextual coverage. This survey provides a systematic and comprehensive overview of these developments, integrating both algorithmic innovations and hardware-level considerations. In addition, we analyze the incorporation of efficient attention into largescale pre-trained language models, including both architectures built entirely on efficient attention and hybrid designs that combine local and global components. By aligning theoretical foundations with practical deployment strategies, this work aims to serve as a foundational reference for advancing the design of scalable and efficient language models.
[130] Legal$Δ$: Enhancing Legal Reasoning in LLMs via Reinforcement Learning with Chain-of-Thought Guided Information Gain
Xin Dai, Buqiang Xu, Zhenghao Liu, Yukun Yan, Huiyuan Xie, Xiaoyuan Yi, Shuo Wang, Ge Yu
Main category: cs.CL
TL;DR: LegalΔ is a reinforcement learning framework that enhances legal reasoning in LLMs by maximizing information gain between direct answers and reasoning-augmented outputs, improving both accuracy and interpretability without labeled preference data.
Details
Motivation: Existing legal LLMs struggle with generating reliable and interpretable reasoning processes, often defaulting to fast-thinking behavior with direct answers lacking rigorous justification needed for complex legal scenarios.Method: LegalΔ uses a reinforcement learning framework with dual-mode input (direct answer vs reasoning-augmented) to maximize information gain between modes. It follows a two-stage approach: (1) distilling reasoning capabilities from DeepSeek-R1, and (2) refining reasoning quality via differential comparisons with multidimensional rewards assessing structural coherence and legal-domain specificity.
Result: Experimental results on multiple legal reasoning tasks show LegalΔ outperforms strong baselines in both accuracy and interpretability, producing more robust and trustworthy legal judgments without relying on labeled preference data.
Conclusion: LegalΔ successfully addresses the interpretability challenge in legal AI by enhancing reasoning quality through information gain maximization, demonstrating improved performance in legal decision-making tasks.
Abstract: Legal Artificial Intelligence (LegalAI) has achieved notable advances in automating judicial decision-making with the support of Large Language Models (LLMs). However, existing legal LLMs still struggle to generate reliable and interpretable reasoning processes. They often default to fast-thinking behavior by producing direct answers without explicit multi-step reasoning, limiting their effectiveness in complex legal scenarios that demand rigorous justification. To address this challenge, we propose Legal$Δ$, a reinforcement learning framework designed to enhance legal reasoning through chain-of-thought guided information gain. During training, Legal$Δ$ employs a dual-mode input setup-comprising direct answer and reasoning-augmented modes-and maximizes the information gain between them. This encourages the model to acquire meaningful reasoning patterns rather than generating superficial or redundant explanations. Legal$Δ$ follows a two-stage approach: (1) distilling latent reasoning capabilities from a powerful Large Reasoning Model (LRM), DeepSeek-R1, and (2) refining reasoning quality via differential comparisons, combined with a multidimensional reward mechanism that assesses both structural coherence and legal-domain specificity. Experimental results on multiple legal reasoning tasks demonstrate that Legal$Δ$ outperforms strong baselines in both accuracy and interpretability. It consistently produces more robust and trustworthy legal judgments without relying on labeled preference data. All code and data will be released at https://github.com/NEUIR/LegalDelta.
[131] DeepScholar-Bench: A Live Benchmark and Automated Evaluation for Generative Research Synthesis
Liana Patel, Negar Arabzadeh, Harshit Gupta, Ankita Sundar, Ion Stoica, Matei Zaharia, Carlos Guestrin
Main category: cs.CL
TL;DR: DeepScholar-bench: A live benchmark and automated evaluation framework for generative research synthesis systems that generate related work sections by retrieving and citing prior work from recent ArXiv papers.
Details
Motivation: Existing benchmarks for AI research synthesis systems are inadequate - they focus on short factual answers, risk staleness and data contamination, and don't capture the complexity and evolving nature of real research synthesis tasks like generating comprehensive literature reviews.Method: Created DeepScholar-bench with queries and human-written exemplars from recent high-quality ArXiv papers. Evaluates systems on generating related work sections by retrieving, synthesizing, and citing prior work. Includes automated framework measuring knowledge synthesis, retrieval quality, and verifiability across three dimensions.
Result: Benchmark is far from saturated - no system surpasses 31% geometric mean across all metrics. Evaluated prior open-source systems, search agents with strong models, OpenAI’s DeepResearch, and their own DeepScholar-ref baseline.
Conclusion: DeepScholar-bench addresses critical evaluation gap for generative research synthesis systems and provides foundation for advancing AI systems capable of automated research synthesis. The benchmark highlights both difficulty and importance of this task.
Abstract: The ability to research and synthesize knowledge is central to human expertise and progress. A new class of AI systems–designed for generative research synthesis–aims to automate this process by retrieving information from the live web and producing long-form, cited reports. Yet, evaluating such systems remains an open challenge: existing question-answering benchmarks focus on short, factual answers, while expert-curated datasets risk staleness and data contamination. Neither captures the complexity and evolving nature of real research synthesis tasks. We introduce DeepScholar-bench, a live benchmark and automated evaluation framework for generative research synthesis. DeepScholar-bench draws queries and human-written exemplars from recent, high-quality ArXiv papers and evaluates a real synthesis task: generating a related work section by retrieving, synthesizing, and citing prior work. Our automated framework holistically measures performance across three key dimensions–knowledge synthesis, retrieval quality, and verifiability. To further future work, we also contribute DeepScholar-ref, a simple, open-source reference pipeline, which is implemented on the LOTUS framework and provides a strong baseline. Using DeepScholar-bench, we systematically evaluate prior open-source systems, search agents with strong models, OpenAI’s DeepResearch, and DeepScholar-ref. We find DeepScholar-bench is far from saturated: no system surpasses a geometric mean of $31%$ across all metrics. These results highlight both the difficulty and importance of DeepScholar-bench as a foundation for advancing AI systems capable of generative research synthesis. We make our benchmark code and data available at https://github.com/guestrin-lab/deepscholar-bench.
[132] Towards EnergyGPT: A Large Language Model Specialized for the Energy Sector
Amal Chebbi, Babajide Kolade
Main category: cs.CL
TL;DR: EnergyGPT is a domain-specialized language model for the energy sector, created by fine-tuning LLaMA 3.1-8B on curated energy texts using both full-parameter and LoRA-based approaches.
Details
Motivation: General-purpose LLMs lack effectiveness in specialized fields like energy that require deep technical expertise and precise domain knowledge. There's a need for domain-specialized models that can handle energy-specific language understanding and generation tasks.Method: Fine-tuned LLaMA 3.1-8B on a high-quality curated corpus of energy-related texts using two adaptation strategies: 1) full-parameter Supervised Fine-Tuning, and 2) parameter-efficient LoRA-based variant updating only a small fraction of parameters. Developed complete pipeline including data collection/curation, fine-tuning, benchmark design, LLM-judge choice, evaluation, and deployment.
Result: Both EnergyGPT variants consistently outperform the base LLaMA model in most energy-related language understanding and generation tasks. The LoRA variant achieves competitive performance gains at significantly reduced training cost compared to full-parameter fine-tuning.
Conclusion: Domain specialization through fine-tuning enables improvements in domain relevance and performance without requiring large-scale infrastructure. Parameter-efficient methods like LoRA offer cost-effective alternatives for creating specialized models.
Abstract: Large language models have demonstrated impressive capabilities across various domains. However, their general-purpose nature often limits their effectiveness in specialized fields such as energy, where deep technical expertise and precise domain knowledge are essential. In this paper, we introduce EnergyGPT, a domain-specialized language model tailored for the energy sector, developed by fine-tuning the LLaMA 3.1-8B model on a high-quality, curated corpus of energy-related texts. We consider two adaptation strategies: a full-parameter Supervised Fine-Tuning variant and a parameter-efficient LoRA-based variant that updates only a small fraction of the model parameters. We present a complete development pipeline, including data collection and curation, model fine-tuning, benchmark design and LLM-judge choice, evaluation, and deployment. Through this work, we demonstrate that our training strategy enables improvements in domain relevance and performance without the need for large-scale infrastructure. By evaluating the performance of both EnergyGPT variants using domain-specific question-answering benchmarks, our results show that the adapted models consistently outperform the base model in most energy-related language understanding and generation tasks, with the LoRA variant achieving competitive gains at significantly reduced training cost.
[133] No Answer Needed: Predicting LLM Answer Accuracy from Question-Only Linear Probes
Iván Vicente Moreno Cencerrado, Arnau Padrés Masdemont, Anton Gonzalvez Hawthorne, David Demitri Africa, Lorenzo Pacchiardi
Main category: cs.CL
TL;DR: LLMs contain internal activations that can predict answer correctness before generation, with probes trained on trivia questions generalizing to diverse knowledge tasks but failing on mathematical reasoning.
Details
Motivation: To understand whether LLMs internally anticipate when they will answer correctly, and to study the internal representations that encode confidence and correctness before token generation.Method: Extract activations after question reading but before token generation, train linear probes to predict forthcoming answer correctness, test across three open-source model families (7-70B parameters) on trivia questions, and evaluate generalization to diverse out-of-distribution knowledge datasets.
Result: Linear probes trained on generic trivia questions successfully predict correctness in-distribution and generalize to diverse OOD knowledge datasets, outperforming black-box baselines and verbalized confidence. Predictive power saturates in intermediate layers, but generalization fails on mathematical reasoning questions. The same direction also captures confidence for “I don’t know” responses.
Conclusion: LLMs contain internal “in-advance correctness directions” that encode confidence and correctness predictions before generation, contributing to understanding LLM internals and complementing previous work on truthfulness and behavior analysis.
Abstract: Do large language models (LLMs) anticipate when they will answer correctly? To study this, we extract activations after a question is read but before any tokens are generated, and train linear probes to predict whether the model’s forthcoming answer will be correct. Across three open-source model families ranging from 7 to 70 billion parameters, projections on this “in-advance correctness direction” trained on generic trivia questions predict success in distribution and on diverse out-of-distribution knowledge datasets, indicating a deeper signal than dataset-specific spurious features, and outperforming black-box baselines and verbalised predicted confidence. Predictive power saturates in intermediate layers and, notably, generalisation falters on questions requiring mathematical reasoning. Moreover, for models responding “I don’t know”, doing so strongly correlates with the probe score, indicating that the same direction also captures confidence. By complementing previous results on truthfulness and other behaviours obtained with probes and sparse auto-encoders, our work contributes essential findings to elucidate LLM internals.
[134] No Prompt Left Behind: Exploiting Zero-Variance Prompts in LLM Reinforcement Learning via Entropy-Guided Advantage Shaping
Thanh-Long V. Le, Myeongho Jeon, Kim Vu, Viet Lai, Eunho Yang
Main category: cs.CL
TL;DR: RL-ZVP improves LLM reasoning by learning from zero-variance prompts where all responses get same reward, unlike existing methods that ignore them.
Details
Motivation: Current RLVR methods like GRPO only use prompts where model responses differ in correctness, ignoring zero-variance prompts where all responses receive the same reward. The authors argue these prompts aren't useless and can provide meaningful feedback for policy optimization.Method: Introduces RL-ZVP algorithm that extracts learning signals from zero-variance prompts by directly rewarding correctness and penalizing errors even without contrasting responses. Modulates feedback with token-level characteristics to preserve informative, nuanced signals.
Result: Across six math reasoning benchmarks, RL-ZVP achieves significant improvements of up to 8.61 points in accuracy and 7.77 points in pass rate over GRPO, consistently outperforming other baselines that filter out zero-variance prompts.
Conclusion: Zero-variance prompts have untapped potential for learning in RLVR, and RL-ZVP effectively leverages them to improve LLM reasoning abilities beyond existing methods.
Abstract: Reinforcement Learning with Verifiable Rewards (RLVR) is a powerful framework for improving the reasoning abilities of Large Language Models (LLMs). However, current methods such as GRPO rely only on problems where the model responses to the same input differ in correctness, while ignoring those where all responses receive the same reward – so-called zero-variance prompts. In this work, we argue that such prompts are not useless but can, in fact, provide meaningful feedback for policy optimization. To this end, we introduce Reinforcement Learning with Zero-Variance Prompts (RL-ZVP), a novel algorithm that extract learning signals from zero-variance prompts. RL-ZVP directly rewards correctness and penalizes errors even without contrasting responses, modulating feedback with token-level characteristics to preserve informative, nuanced signals. Across six math reasoning benchmarks, RL-ZVP achieves significant improvements of up to 8.61 points in accuracy and 7.77 points in pass rate over GRPO, while consistently outperforming other baselines that filter out zero-variance prompts. These results highlight the untapped potential of learning from zero-variance prompts in RLVR. The project page is available at https://bltnynk.github.io/publications/rl-zvp/.
[135] HEART: Emotionally-Driven Test-Time Scaling of Language Models
Gabriela Pinto, Palash Goyal, Mihir Parmar, Yiwen Song, Souradip Chakraborty, Zifeng Wang, Jingsun Yoon, Hamid Palangi, Tomas Pfister
Main category: cs.CL
TL;DR: HEART is a test-time scaling framework that uses emotional cues (alternating critical and encouraging tones) to guide AI models out of repetitive, incorrect reasoning patterns and improve problem-solving performance.
Details
Motivation: Current test-time scaling methods often get stuck in repetitive, incorrect patterns of thought, limiting their problem-solving effectiveness. The authors propose that emotional guidance, similar to how feelings contribute to human decision-making, could help models break out of dead-end reasoning.Method: HEART uses emotional cues to guide model focus by alternating between critical tones (to sharpen error detection) and encouraging tones (to spark new ideas). This affective regulation framework is applied during test-time scaling to help models escape unproductive reasoning patterns.
Result: HEART was evaluated across seven high-difficulty benchmarks including Humanity’s Last Exam, GPQA Diamond, and LiveCodeBench. Results show consistent accuracy gains over affect-sterile baselines, demonstrating robustness across diverse models and that emotion facilitates deeper reasoning.
Conclusion: The strategic integration of affective regulation can significantly improve machine reasoning by guiding logical synthesis. Emotional cues help models break out of dead-end reasoning patterns, suggesting that the next frontier in machine reasoning lies in incorporating affective elements.
Abstract: Test-time scaling has significantly improved how AI models solve problems, yet current methods often get stuck in repetitive, incorrect patterns of thought. We introduce HEART, a framework that uses emotional cues to guide the model’s focus, much like how feelings contribute to human decision-making. By alternating between critical tones to sharpen error detection and encouraging tones to spark new ideas, HEART helps the model break out of dead-end reasoning and find the right solution. We evaluate HEART across seven high-difficulty benchmarks–including Humanity’s Last Exam, GPQA Diamond, and LiveCodeBench–demonstrating robustness across diverse models. Results show that emotion facilitates deeper reasoning, yielding consistent accuracy gains over affect-sterile baselines. These findings suggest that the next frontier in machine reasoning lies in the strategic integration of affective regulation to guide logical synthesis.
[136] Same Content, Different Representations: A Controlled Study for Table QA
Yue Zhang, Seiji Maekawa, Nikita Bhutani
Main category: cs.CL
TL;DR: Study isolates table representation effects on Table QA performance by comparing structured vs semi-structured tables with identical content, revealing trade-offs between SQL methods, LLMs, and hybrid approaches.
Details
Motivation: Existing Table QA benchmarks are tied to fixed data formats and haven't systematically examined how table representation itself affects model performance, despite real-world settings requiring operation over both structured databases and semi-structured tables with textual fields.Method: Created RePairTQA diagnostic benchmark with controlled table representations using verbalization pipeline to generate paired structured and semi-structured tables with identical content. Conducted experiments across splits varying table size, join requirements, query complexity, and schema quality.
Result: SQL-based methods achieve high accuracy on structured inputs but degrade on semi-structured data; LLMs exhibit flexibility but reduced precision; hybrid approaches strike a balance, particularly under noisy schemas. Effects intensify with larger tables and more complex queries.
Conclusion: No single method excels across all conditions, highlighting the central role of representation in shaping Table QA performance. Findings provide insights for model selection and design, paving way for more robust hybrid approaches suited for diverse real-world data formats.
Abstract: Table Question Answering (Table QA) in real-world settings must operate over both structured databases and semi-structured tables containing textual fields. However, existing benchmarks are tied to fixed data formats and have not systematically examined how representation itself affects model performance. We present the first controlled study that isolates the role of table representation by holding content constant while varying structure. Using a verbalization pipeline, we generate paired structured and semi-structured tables, enabling direct comparisons across modeling paradigms. To support detailed analysis, we introduce RePairTQA, a diagnostic benchmark with splits along table size, join requirements, query complexity, and schema quality. Our experiments reveal consistent trade-offs: SQL-based methods achieve high accuracy on structured inputs but degrade on semi-structured data, LLMs exhibit flexibility but reduced precision, and hybrid approaches strike a balance, particularly under noisy schemas. These effects intensify with larger tables and more complex queries. Ultimately, no single method excels across all conditions, and we highlight the central role of representation in shaping Table QA performance. Our findings provide actionable insights for model selection and design, paving the way for more robust hybrid approaches suited for diverse real-world data formats.
[137] Do Language Models Update their Forecasts with New Information?
Zhangdie Yuan, Zifeng Ding, Andreas Vlachos
Main category: cs.CL
TL;DR: EvolveCast framework evaluates LLMs’ ability to appropriately revise forecasts and confidence when presented with new information, finding models are often inconsistent or overly conservative compared to human forecasters.
Details
Motivation: Prior work treats forecasting as static, failing to consider how forecasts and confidence should evolve with new evidence. There's a gap in evaluating whether LLMs appropriately revise forecasts when presented with post-training information.Method: Introduces EvolveCast framework to assess LLM forecast updates in response to new information released after training cutoff. Uses human forecasters as comparative reference for forecast updates and confidence calibration under new information.
Result: LLMs show some responsiveness to new information but updates are often inconsistent or overly conservative. Both verbalized and logits-based confidence estimates remain far from human reference standard. Models tend to be conservative across various LLM settings.
Conclusion: Current approaches (e.g., RAG-based methods) for updating model knowledge are insufficient for probabilistic reasoning; models treat new information as retrieval context rather than evidence that shifts posterior probability. Need more robust mechanisms for incorporating external knowledge into belief dynamics.
Abstract: Prior work has largely treated forecasting as a static task, failing to consider how forecasts and the confidence in them should evolve as new evidence emerges. To address this gap, we introduce EvolveCast, a framework for evaluating whether large language models revise their forecasts appropriately in response to new information. In particular, EvolveCast assesses whether LLMs update their forecasts when presented with information released after their training cutoff. We use human forecasters as a comparative reference to assess forecast updates and confidence calibration under new information. While LLMs demonstrate some responsiveness to new information, their updates are often inconsistent or overly conservative. We further find that both verbalized and logits-based confidence estimates remain far from the human reference standard. Across settings with a variety of LLMs, models tend to be conservative in updating their forecasts. These findings suggest that current approaches (e.g., RAG-based methods) for updating model knowledge are insufficient for probabilistic reasoning; models treat new information as retrieval context rather than evidence that shifts posterior probability. EvolveCast thus underscores the need for more robust mechanisms to incorporate external knowledge into belief dynamics.
[138] Bringing Emerging Architectures to Sequence Labeling in NLP
Ana Ezquerro, Carlos Gómez-Rodríguez, David Vilares
Main category: cs.CL
TL;DR: Study comparing alternative architectures (xLSTMs, SSMs, diffusion, adversarial) to Transformers for sequence labeling across diverse tagging tasks, finding limited generalization of alternative methods.
Details
Motivation: While Transformer encoders dominate sequence labeling, alternative architectures have shown promise in language modeling but haven't been thoroughly evaluated on diverse sequence labeling tasks with varying structural complexity.Method: Systematic evaluation of xLSTMs, structured state-space models, diffusion models, and adversarial learning across tagging tasks with different structural complexity, label spaces, and token dependencies, spanning multiple languages.
Result: Alternative architectures’ strong performance in simpler settings doesn’t generalize well across languages/datasets or extend to more complex structured tasks; Transformers remain dominant.
Conclusion: Alternative architectures need further development to match Transformers’ robustness across diverse sequence labeling tasks, highlighting the need for more comprehensive evaluation beyond simple benchmarks.
Abstract: Pretrained Transformer encoders are the dominant approach to sequence labeling. While some alternative architectures-such as xLSTMs, structured state-space models, diffusion models, and adversarial learning-have shown promise in language modeling, few have been applied to sequence labeling, and mostly on flat or simplified tasks. We study how these architectures adapt across tagging tasks that vary in structural complexity, label space, and token dependencies, with evaluation spanning multiple languages. We find that the strong performance previously observed in simpler settings does not always generalize well across languages or datasets, nor does it extend to more complex structured tasks.
[139] Towards Reliable Benchmarking: A Contamination Free, Controllable Evaluation Framework for Multi-step LLM Function Calling
Seiji Maekawa, Jackson Hassell, Pouya Pezeshkpour, Tom Mitchell, Estevam Hruschka
Main category: cs.CL
TL;DR: FuncBenchGen is a contamination-free framework for evaluating tool-augmented language models by generating synthetic multi-step tool-use tasks as function-dependency graph traversal problems.
Details
Motivation: Existing benchmarks for tool-augmented language models lack fine-grained control over task difficulty and are vulnerable to data contamination, making it hard to properly evaluate model capabilities in multi-step tool use scenarios.Method: The framework casts tool use as traversal over a hidden function-dependency DAG where models must infer the correct sequence of function calls to compute a target value. It allows precise control over task difficulty through parameters like graph size, dependency depth, and distractor functions while avoiding data contamination.
Result: Reasoning-optimized models outperform general-purpose models, with GPT-5 performing best. Performance declines sharply with increased dependency depth, and connected distractors are especially challenging. Models often make syntactically valid calls but propagate incorrect values across steps, revealing brittle state tracking.
Conclusion: The study reveals fundamental limitations in LLMs’ multi-turn tool use capabilities, particularly in state tracking. A simple mitigation strategy of explicitly restating prior variable values at each step yields substantial performance gains across models, suggesting promising directions for improving tool-augmented language models.
Abstract: Existing benchmarks for tool-augmented language models (TaLMs) lack fine-grained control over task difficulty and remain vulnerable to data contamination. We present FuncBenchGen, a unified, contamination-free framework that evaluates TaLMs by generating synthetic multi-step tool-use tasks to stress-test TaLMs. The key idea is to cast tool use as traversal over a hidden function-dependency DAG where models must infer the correct sequence of calls to compute a target value. FuncBenchGen allows precise control over task difficulty (e.g., graph size, dependency depth, and distractor functions) while avoiding pretraining/test-time leakage. Our evaluation demonstrates reasoning-optimized models consistently outperform general-purpose models with GPT-5 significantly outperforming other available models. Performance declines sharply as dependency depth increases. Furthermore, connected distractors – irrelevant functions sharing type-compatible variables with relevant functions – prove especially difficult to handle. Also, strong models often make syntactically valid function calls but propagate incorrect or stale argument values across steps, revealing brittle state tracking by LLMs in multi-turn tool use. Motivated by this observation, we introduce a simple mitigation strategy that explicitly restates prior variable values to the agent at each step. Surprisingly, this lightweight change yields substantial gains across models. e.g., yielding an improvement in success rate from 62.5% to 81.3% for GPT-5.
[140] Copy-Paste to Mitigate Large Language Model Hallucinations
Yongchao Long, Xian Wu, Yingying Zhang, Xianbin Wen, Yuxi Zhou, Shenda Hong
Main category: cs.CL
TL;DR: CopyPasteLLM improves contextual faithfulness in RAG by training LLMs to copy more from provided context, reducing hallucinations through increased contextual reliance.
Details
Motivation: LLMs in RAG systems often don't fully trust provided context, leading to context-unfaithful hallucinations that undermine reliability. The authors observed an inverse correlation between response copying degree and hallucinations.Method: Two-stage high-copying response preference training with three prompting methods to enhance copying degree. Uses automated pipeline to transform generated responses into high-copying preference data. Proposes Context-Parameter Copying Capturing algorithm to analyze model behavior.
Result: CopyPasteLLM achieves best performance on FaithEval, ConFiQA and PubMedQA, with 12.2% to 24.5% accuracy improvements on FaithEval over best baselines, using only 365 training samples (1/50th of baseline data).
Conclusion: Training LLMs to copy more from context improves contextual faithfulness and reduces hallucinations. CopyPasteLLM recalibrates reliance from internal parametric knowledge to external context during generation.
Abstract: While Retrieval-Augmented Generation (RAG) enables large language models (LLMs) to generate contextually grounded responses, contextual faithfulness remains challenging as LLMs may not consistently trust provided context, leading to hallucinations that undermine reliability. We observe an inverse correlation between response copying degree and context-unfaithful hallucinations on RAGTruth, suggesting that higher copying degrees reduce hallucinations by fostering genuine contextual belief. We propose CopyPasteLLM, obtained through two-stage high-copying response preference training. We design three prompting methods to enhance copying degree, demonstrating that high-copying responses achieve superior contextual faithfulness and hallucination control. These approaches enable a fully automated pipeline that transforms generated responses into high-copying preference data for training CopyPasteLLM. On FaithEval, ConFiQA and PubMedQA, CopyPasteLLM achieves best performance in both counterfactual and original contexts, remarkably with 12.2% to 24.5% accuracy improvements on FaithEval over the best baseline, while requiring only 365 training samples – 1/50th of baseline data. To elucidate CopyPasteLLM’s effectiveness, we propose the Context-Parameter Copying Capturing algorithm. Interestingly, this reveals that CopyPasteLLM recalibrates reliance on internal parametric knowledge rather than external knowledge during generation. All codes are available at https://github.com/longyongchao/CopyPasteLLM
[141] Towards Open-Ended Discovery for Low-Resource NLP
Bonaventure F. P. Dossou, Henri Aïdasso
Main category: cs.CL
TL;DR: Position paper advocating for interactive, dialogue-based AI systems that learn low-resource languages dynamically through human-machine collaboration rather than static datasets.
Details
Motivation: NLP for low-resource languages is constrained by lack of textual corpora, standardized orthographies, and scalable annotation pipelines. Current large language models remain inaccessible to underrepresented communities due to reliance on massive pre-collected data and centralized infrastructure.Method: Proposes a framework grounded in joint human-machine uncertainty, combining epistemic uncertainty from the model with hesitation cues and confidence signals from human speakers to guide interaction, query selection, and memory retention.
Result: Conceptual framework and call to action rather than empirical results. Advocates for a paradigm shift from static data collection to interactive, uncertainty-driven discovery.
Conclusion: Future language technology for low-resource languages must move toward interactive, cooperative model building between AI systems and speakers, emphasizing participatory, co-adaptive learning processes that respect and empower communities.
Abstract: Natural Language Processing (NLP) for low-resource languages remains fundamentally constrained by the lack of textual corpora, standardized orthographies, and scalable annotation pipelines. While recent advances in large language models have improved cross-lingual transfer, they remain inaccessible to underrepresented communities due to their reliance on massive, pre-collected data and centralized infrastructure. In this position paper, we argue for a paradigm shift toward open-ended, interactive language discovery, where AI systems learn new languages dynamically through dialogue rather than static datasets. We contend that the future of language technology, particularly for low-resource and under-documented languages, must move beyond static data collection pipelines toward interactive, uncertainty-driven discovery, where learning emerges dynamically from human-machine collaboration instead of being limited to pre-existing datasets. We propose a framework grounded in joint human-machine uncertainty, combining epistemic uncertainty from the model with hesitation cues and confidence signals from human speakers to guide interaction, query selection, and memory retention. This paper is a call to action: we advocate a rethinking of how AI engages with human knowledge in under-documented languages, moving from extractive data collection toward participatory, co-adaptive learning processes that respect and empower communities while discovering and preserving the world’s linguistic diversity. This vision aligns with principles of human-centered AI, emphasizing interactive, cooperative model building between AI systems and speakers.
[142] Luth: Efficient French Specialization for Small Language Models and Cross-Lingual Transfer
Maxence Lasbordes, Sinoué Gad
Main category: cs.CL
TL;DR: Luth is a family of French-specialized Small Language Models that outperform other open-source models on French benchmarks while maintaining English capabilities through targeted post-training and strategic model merging.
Details
Motivation: The paper addresses the English-centric bias in Large Language Models, which creates significant performance gaps for other major languages like French, especially in Small Language Models. Existing multilingual models show much lower performance in French compared to English, and there's limited research on efficient adaptation methods for French.Method: The authors introduce Luth models through targeted post-training on curated, high-quality French data. They further enhance performance through strategic model merging techniques that improve capabilities in both French and English.
Result: Luth models outperform all open-source counterparts of comparable size on multiple French benchmarks while retaining their original English capabilities. Strategic model merging establishes Luth as a new state-of-the-art for French SLMs.
Conclusion: Luth provides a robust baseline for future French-language research and demonstrates that targeted adaptation can effectively address language performance gaps in Small Language Models while maintaining multilingual capabilities.
Abstract: The landscape of Large Language Models remains predominantly English-centric, resulting in a significant performance gap for other major languages, such as French, especially in the context of Small Language Models (SLMs). Existing multilingual models demonstrate considerably lower performance in French compared to English, and research on efficient adaptation methods for French remains limited. To address this, we introduce \textbf{Luth}, a family of French-specialized SLMs: through targeted post-training on curated, high-quality French data, our models outperform all open-source counterparts of comparable size on multiple French benchmarks while retaining their original English capabilities. We further show that strategic model merging enhances performance in both languages, establishing Luth as a new state of the art for French SLMs and a robust baseline for future French-language research.
[143] MASA: Rethinking the Representational Bottleneck in LoRA with Multi-A Shared Adaptation
Qin Dong, Yuntian Tang, Heming Jia, Yunhang Shen, Bohan Jia, Wenxuan Huang, Lianyue Zhang, Jiao Xie, Shaohui Lin, Rongrong Ji
Main category: cs.CL
TL;DR: MASA introduces a multi-A, single-B LoRA variant that uses multiple specialized down-projection experts to capture diverse features, improving downstream task adaptation while maintaining parameter efficiency.
Details
Motivation: Standard LoRA's reliance on a single down-projection matrix creates a representational bottleneck that is insufficient for capturing diverse signals required by complex tasks, motivating the need for enriched feature adaptation.Method: MASA implements a multi-A, single-B structure where multiple specialized down-projection experts capture diverse features, asymmetrically shared across layers, and integrated by layer-specific up-projection matrices for parameter efficiency.
Result: On MMLU benchmark, MASA achieves 59.62% average accuracy, outperforming standard LoRA by 1.08 points (1.84% relative improvement) with comparable learnable parameters of 0.52%.
Conclusion: MASA effectively addresses LoRA’s representational bottleneck through multi-expert feature adaptation, demonstrating improved performance across multi-domain generalization, single-domain specialization, and multi-task reasoning tasks.
Abstract: Low-Rank Adaptation (LoRA) has emerged as a dominant method in Parameter-Efficient Fine-Tuning (PEFT) for large language models, which augments the transformer layer with one down-projection $A$ and one up-projection $B$. However, LoRA’s reliance on a single down-projection matrix ($A$) creates a representational bottleneck, as this solitary feature extractor is inherently insufficient for capturing the diverse signals required by complex tasks. This motivates our architectural shift to focus on enriching the feature adaptation to improve the downstream task adaptation ability. We propose MASA (Multi-$A$ Shared Adaptation), an architecture that implements a multi-$A$, single-$B$ structure where the multi-$A$ expert ensemble is asymmetrically shared across layers to ensure parameter efficiency. In MASA, these specialized experts capture diverse features, which are then integrated by a single, layer-specific $B$-matrix. The effectiveness and versatility of our method are validated through a comprehensive suite of experiments spanning multi-domain generalization, single-domain specialization, and multi-task reasoning. For example, on the MMLU benchmark, MASA achieves an average accuracy of 59.62%, outperforming the standard LoRA by 1.08 points (a relative improvement of 1.84%) with comparable learnable parameters of 0.52%.
[144] CoMAS: Co-Evolving Multi-Agent Systems via Interaction Rewards
Xiangyuan Xue, Yifan Zhou, Guibin Zhang, Zaibin Zhang, Yijiang Li, Chen Zhang, Zhenfei Yin, Philip Torr, Wanli Ouyang, Lei Bai
Main category: cs.CL
TL;DR: CoMAS enables LLM-based agents to self-evolve through multi-agent discussions and collaboration, using interaction-based intrinsic rewards and LLM-as-judge mechanisms for RL optimization.
Details
Motivation: Current RL-based self-evolution methods for LLM agents rely on external rewards or simple intrinsic signals, diverging from human-like learning through discussion and collaboration. The authors aim to create a more natural self-evolution mechanism inspired by human mutual learning.Method: CoMAS framework enables agents to improve through inter-agent interactions without external supervision. It generates intrinsic rewards from discussion dynamics, uses LLM-as-a-judge to formulate these rewards, and optimizes each agent’s policy through reinforcement learning for decentralized co-evolution.
Result: CoMAS consistently outperforms untrained agents and achieves state-of-the-art performance across most evaluation settings. Ablation studies confirm the necessity of interaction-based reward signals and show promising scalability with increasing number and diversity of agents.
Conclusion: CoMAS establishes a novel and effective paradigm for self-evolution in LLM-based agents, demonstrating that multi-agent collaboration and discussion-based learning can drive autonomous improvement without external supervision.
Abstract: Self-evolution is a central research topic in enabling large language model (LLM)-based agents to continually improve their capabilities after pretraining. Recent research has witnessed a transition from reinforcement learning (RL)-free to RL-based methods. Current RL-based methods either rely on dense external reward signals or extract intrinsic reward signals from LLMs themselves. However, these approaches diverge from the self-evolution mechanisms observed in human intelligence, where individuals learn and improve through mutual discussion and collaboration. In this work, we introduce Co-Evolving Multi-Agent Systems (CoMAS), a novel framework that enables agents to improve autonomously by learning from inter-agent interactions without external supervision. CoMAS generates intrinsic rewards from rich discussion dynamics, employs an LLM-as-a-judge mechanism to formulate these rewards, and optimizes each agent’s policy through RL, thereby enabling decentralized and scalable co-evolution. Experimental results demonstrate that CoMAS consistently outperforms untrained agents and achieves state-of-the-art performance across most evaluation settings. Ablation studies confirm the necessity of interaction-based reward signals and reveal promising scalability as the number and diversity of agents increase. These findings establish CoMAS as a novel and effective paradigm for self-evolution in LLM-based agents.
[145] Diffusion-Inspired Masked Fine-Tuning for Knowledge Injection in Autoregressive LLMs
Xu Pan, Ely Hahami, Jingxuan Fan, Ziqian Xie, Haim Sompolinsky
Main category: cs.CL
TL;DR: Diffusion LLMs (dLLMs) learn new factual knowledge more effectively than autoregressive LLMs (arLLMs) without needing paraphrase augmentation, and masked fine-tuning can give arLLMs similar knowledge injection advantages.
Details
Motivation: LLMs need to update factual knowledge as facts evolve, but current fine-tuning methods suffer from compute-heavy paraphrase augmentation and the reversal curse. Recent findings suggest dLLMs may learn new knowledge more easily than arLLMs.Method: 1) Controlled knowledge fine-tuning experiments comparing dLLMs and arLLMs, 2) Proposed masked fine-tuning for arLLMs where models reconstruct original text from masked versions, 3) Applied demasking objective to supervised fine-tuning on math tasks.
Result: dLLMs achieve high QA accuracy without paraphrase augmentation, while arLLMs require paraphrases. Masked fine-tuning enables arLLMs to match dLLMs’ knowledge injection capabilities (no paraphrase needed, reversal curse resistant). Demasking objective also improves SFT on math tasks.
Conclusion: The demasking objective (used in diffusion models) provides superior knowledge injection capabilities, and this advantage can be transferred to arLLMs through masked fine-tuning, suggesting broader applicability of demasking for model training.
Abstract: Large language models (LLMs) are often used in environments where facts evolve, yet factual knowledge updates via fine-tuning on unstructured text often suffers from 1) reliance on compute-heavy paraphrase augmentation and 2) the reversal curse. Recent studies show diffusion large language models (dLLMs) require fewer training samples to achieve lower loss in pre-training and are more resistant to the reversal curse, suggesting dLLMs may learn new knowledge more easily than autoregressive LLMs (arLLMs). We test this hypothesis in controlled knowledge fine-tuning experiments and find that while arLLMs rely on paraphrase augmentation to generalize knowledge text into question-answering (QA) capability, dLLMs do not require paraphrases to achieve high QA accuracy. To further investigate whether the demasking objective alone can induce such a knowledge injection advantage in dLLMs regardless of their diffusion denoising paradigm, we propose masked fine-tuning for arLLMs, which prompts an arLLM to reconstruct the original text given a masked version in context. The masked fine-tuning for arLLMs substantially improves the efficacy of knowledge injection, i.e. no paraphrase needed and resistant to the reversal curse, closing the gap between arLLMs and dLLMs. We also demonstrate that the same demasking objective improves supervised fine-tuning (SFT) on math tasks over standard SFT, suggesting broader applicability of the demasking objective.
[146] What Layers When: Learning to Skip Compute in LLMs with Residual Gates
Filipe Laitenberger, Dawid Kopiczko, Cees G. M. Snoek, Yuki M. Asano
Main category: cs.CL
TL;DR: GateSkip introduces token-wise layer skipping via residual-stream gating that enables compute savings while maintaining accuracy, with stable fine-tuning on pretrained models.
Details
Motivation: To reduce computational costs in large language models during inference while maintaining accuracy, addressing limitations of existing methods like early-exit or router-based approaches that are unstable and require extensive retraining.Method: Adds sigmoid-linear gates to Attention/MLP branches that condense outputs before re-entering residual stream. During inference, ranks tokens by gate values and skips low-importance ones using per-layer budgets, enabling token-wise layer skipping.
Result: Achieves up to 15% compute savings on long-form reasoning while retaining over 90% baseline accuracy. For larger models, tradeoff improves. On instruction-tuned models, shows accuracy gains at full compute and matches baseline quality near 50% savings.
Conclusion: GateSkip provides stable, fine-tunable token-wise layer skipping that offers computational efficiency without extensive retraining, with insights into transformer information flow and compatibility with other optimization techniques.
Abstract: We introduce GateSkip, a simple residual-stream gating mechanism that enables token-wise layer skipping in decoder-only LMs. Each Attention/MLP branch is equipped with a sigmoid-linear gate that condenses the branch’s output before it re-enters the residual stream. During inference we rank tokens by the gate values and skip low-importance ones using a per-layer budget. While early-exit or router-based Mixture-of-Depths models are known to be unstable and need extensive retraining, our smooth, differentiable gates fine-tune stably on top of pretrained models. On long-form reasoning, we save up to 15% compute while retaining over 90% of baseline accuracy. For increasingly larger models, this tradeoff improves drastically. On instruction-tuned models we see accuracy gains at full compute and match baseline quality near 50% savings. The learned gates give insight into transformer information flow (e.g., BOS tokens act as anchors), and the method combines easily with quantization, pruning, and self-speculative decoding.
[147] Modality Matching Matters: Calibrating Language Distances for Cross-Lingual Transfer in URIEL+
York Hay Ng, Aditya Khan, Xiang Lu, Matteo Salloum, Michael Zhou, Phuong H. Hoang, A. Seza Doğruöz, En-Shiun Annie Lee
Main category: cs.CL
TL;DR: A framework for type-matched language distances with structure-aware representations for geography, genealogy, and typology, unified into a composite distance that improves cross-lingual transfer performance.
Details
Motivation: Existing linguistic knowledge bases like URIEL+ have limitations: their one-size-fits-all vector representations don't suit diverse linguistic data structures, and they lack principled methods for aggregating signals into comprehensive scores.Method: Proposed type-matched language distances with structure-aware representations: speaker-weighted distributions for geography, hyperbolic embeddings for genealogy, and latent variables model for typology. Unified these into a robust, task-agnostic composite distance.
Result: Across multiple zero-shot transfer benchmarks, the representations significantly improve transfer performance when distance type is relevant to the task, and the composite distance yields gains in most tasks.
Conclusion: The framework addresses limitations of existing linguistic knowledge bases by providing structure-aware representations and principled aggregation methods, leading to improved cross-lingual transfer performance.
Abstract: Existing linguistic knowledge bases such as URIEL+ provide valuable geographic, genetic and typological distances for cross-lingual transfer but suffer from two key limitations. First, their one-size-fits-all vector representations are ill-suited to the diverse structures of linguistic data. Second, they lack a principled method for aggregating these signals into a single, comprehensive score. In this paper, we address these gaps by introducing a framework for type-matched language distances. We propose novel, structure-aware representations for each distance type: speaker-weighted distributions for geography, hyperbolic embeddings for genealogy, and a latent variables model for typology. We unify these signals into a robust, task-agnostic composite distance. Across multiple zero-shot transfer benchmarks, we demonstrate that our representations significantly improve transfer performance when the distance type is relevant to the task, while our composite distance yields gains in most tasks.
[148] The Reasoning Lingua Franca: A Double-Edged Sword for Multilingual AI
Alan Saji, Raj Dabre, Anoop Kunchukuttan, Ratish Puduppully
Main category: cs.CL
TL;DR: LRMs default to English reasoning for non-English questions, creating performance gaps and translation errors despite better cognitive behaviors in English reasoning traces.
Details
Motivation: Large Reasoning Models (LRMs) show strong performance on reasoning tasks but their multilingual reasoning abilities remain underexplored. When presented with non-English questions, LRMs often default to reasoning in English, raising concerns about interpretability and handling of linguistic/cultural nuances.Method: Systematic comparison of LRM’s reasoning in English versus the language of the question across two tasks: MGSM and GPQA Diamond. Evaluation includes both answer accuracy and analysis of cognitive attributes in reasoning traces.
Result: English reasoning traces show substantially higher presence of cognitive behaviors, and reasoning in English generally yields higher final-answer accuracy, with performance gap increasing as tasks become more complex. However, English-centric strategy is susceptible to “Lost in Translation” failure mode where translation steps lead to errors that would have been avoided by reasoning in the question’s language.
Conclusion: LRMs have significant limitations in multilingual reasoning, defaulting to English with performance trade-offs - better cognitive behaviors and accuracy in English but vulnerable to translation errors. This highlights the need for improved multilingual reasoning capabilities.
Abstract: Large Reasoning Models (LRMs) achieve strong performance on mathematical, scientific, and other question-answering tasks, but their multilingual reasoning abilities remain underexplored. When presented with non-English questions, LRMs often default to reasoning in English, raising concerns about interpretability and the handling of linguistic and cultural nuances. We systematically compare an LRM’s reasoning in English versus the language of the question. Our evaluation spans two tasks: MGSM and GPQA Diamond. Beyond measuring answer accuracy, we also analyze cognitive attributes in the reasoning traces. We find that English reasoning traces exhibit a substantially higher presence of these cognitive behaviors, and that reasoning in English generally yields higher final-answer accuracy, with the performance gap increasing as tasks become more complex. However, this English-centric strategy is susceptible to a key failure mode - getting “Lost in Translation,” where translation steps lead to errors that would have been avoided by reasoning in the language of the question.
[149] PairUni: Pairwise Training for Unified Multimodal Language Models
Jiani Zheng, Zhiyang Teng, Kunpeng Qiu, Xiangtai Li, Anran Wang, Yu Tian, Ye Tian, Haochen Wang, Zhuochen Wang
Main category: cs.CL
TL;DR: PairUni is a unified framework for vision-language models that reorganizes data into understanding-generation pairs and uses pair-aware reinforcement learning to balance both capabilities.
Details
Motivation: Unified Vision-Language Models (UVLMs) need to perform both understanding and generation tasks, but balancing these capabilities in reinforcement learning is challenging due to heterogeneous data and supervision.Method: Constructs unified paired dataset via cross-modal semantic completion and retrieval, then uses PairGRPO (pair-aware Group Relative Policy Optimization) that assigns similarity scores to modulate advantages and reduce task interference.
Result: Consistent improvements across diverse UVLM architectures (autoregressive and discrete diffusion) and scales (1B to 14B), with strong generalization to image editing tasks without editing-specific data.
Conclusion: PairUni effectively balances understanding and generation in UVLMs through structured data pairing and pair-aware RL optimization, demonstrating broad applicability and strong generalization.
Abstract: Unified Vision-Language Models (UVLMs) perform both understanding and generation within a single architecture. Since these models rely on heterogeneous data and supervision, balancing both generation and understanding in reinforcement learning (RL) is challenging. To address this challenge, we propose PairUni, a unified framework that reorganizes data into understanding-generation (UG) pairs and aligns optimization accordingly. Specifically, we construct a unified paired dataset by synthesizing aligned instances via cross-modal semantic completion and retrieving semantically related samples. These paired structures expose cross-task semantic correspondences and support consistent policy learning. To leverage this structure, we present PairGRPO, a pair-aware variant based on Group Relative Policy Optimization. It assigns a similarity score to each pair to modulate the advantage, strengthening learning from well-aligned examples and reducing task interference. Extensive experiments across diverse UVLM architectures (Autoregressive and Discrete Diffusion) and scales (1B to 14B) demonstrate that PairUni yields consistent improvements over strong baselines. Notably, our method also demonstrates strong generalization by improving performance on image editing tasks without using any editing-specific data. Codes are available at https://github.com/Haochen-Wang409/PairUni.
[150] BudgetMem: Learning Selective Memory Policies for Cost-Efficient Long-Context Processing in Language Models
Chandra Vamsi Krishna Alla, Harish Naidu Gaddam, Manohar Kommi
Main category: cs.CL
TL;DR: BudgetMem: A memory-augmented architecture that selectively stores information under strict budget constraints for efficient long-context processing in LLMs, achieving 72.4% memory savings with minimal performance degradation.
Details
Motivation: LLMs face computational and memory constraints when processing long contexts, with existing approaches being prohibitively expensive for resource-constrained deployments despite growing demand for applications requiring reasoning over extensive documents.Method: Combines selective memory policies with feature-based salience scoring (entity density, TF-IDF, discourse markers, position bias) and learned gating mechanisms coupled with BM25 sparse retrieval for efficient information access under budget constraints.
Result: Achieves only 1.0% F1 score degradation while saving 72.4% memory compared to baseline RAG on long documents (5K-10K tokens), with benefits increasing with document length.
Conclusion: Provides a practical pathway for deploying capable long-context systems on modest hardware, democratizing access to advanced language understanding capabilities through efficient memory management.
Abstract: Large Language Models (LLMs) face significant computational and memory constraints when processing long contexts, despite growing demand for applications requiring reasoning over extensive documents, multi-session dialogues, and book length texts. While recent advances have extended context windows to 100K-1M tokens, such approaches incur prohibitive costs for resource constrained deployments. We propose BudgetMem, a novel memory augmented architecture that learns what to remember rather than remembering everything. Our system combines selective memory policies with feature based salience scoring (entity density, TF-IDF, discourse markers, position bias) to decide which information merits storage under strict budget constraints. Unlike existing retrieval augmented generation (RAG) systems that store all chunks, BudgetMem employs learned gating mechanisms coupled with BM25 sparse retrieval for efficient information access. Through comprehensive experiments on 700 question answer pairs across short (237 tokens) and long (5K-10K tokens) documents with Llama-3.2-3B-Instruct, we demonstrate that BudgetMem achieves remarkable results on long documents: only 1.0% F1 score degradation while saving 72.4% memory compared to baseline RAG. We validate our approach through budget sensitivity analysis (testing 7 budget ratios), naive baseline comparisons, and document length analysis, showing that BudgetMem’s benefits increase with document length. Our work provides a practical pathway for deploying capable long context systems on modest hardware, democratizing access to advanced language understanding capabilities.
[151] IDALC: A Semi-Supervised Framework for Intent Detection and Active Learning based Correction
Ankan Mullick, Sukannya Purkayastha, Saransh Sharma, Pawan Goyal, Niloy Ganguly
Main category: cs.CL
TL;DR: IDALC is a semi-supervised framework for intent detection and correction of system-rejected utterances in voice-controlled dialog systems, using active learning to minimize annotation costs.
Details
Motivation: Voice-controlled dialog systems often reject utterances when models have low confidence, requiring manual annotation. As systems evolve with new intents, labeling all rejected utterances becomes impractical and costly.Method: IDALC combines intent detection with active learning-based correction. It identifies user intents and corrects system-rejected utterances using a semi-supervised approach that strategically selects samples for human annotation to minimize labeling effort.
Result: Outperforms baseline methods by 5-10% higher accuracy and 4-8% improvement in macro-F1, while maintaining annotation costs at only 6-10% of available unlabeled data across benchmark datasets.
Conclusion: IDALC provides an efficient solution for intent detection and correction in dialog systems, significantly reducing annotation costs while maintaining high performance through semi-supervised active learning.
Abstract: Voice-controlled dialog systems have become immensely popular due to their ability to perform a wide range of actions in response to diverse user queries. These agents possess a predefined set of skills or intents to fulfill specific user tasks. But every system has its own limitations. There are instances where, even for known intents, if any model exhibits low confidence, it results in rejection of utterances that necessitate manual annotation. Additionally, as time progresses, there may be a need to retrain these agents with new intents from the system-rejected queries to carry out additional tasks. Labeling all these emerging intents and rejected utterances over time is impractical, thus calling for an efficient mechanism to reduce annotation costs. In this paper, we introduce IDALC (Intent Detection and Active Learning based Correction), a semi-supervised framework designed to detect user intents and rectify system-rejected utterances while minimizing the need for human annotation. Empirical findings on various benchmark datasets demonstrate that our system surpasses baseline methods, achieving a 5-10% higher accuracy and a 4-8% improvement in macro-F1. Remarkably, we maintain the overall annotation cost at just 6-10% of the unlabelled data available to the system. The overall framework of IDALC is shown in Fig. 1
[152] Training Language Models to Explain Their Own Computations
Belinda Z. Li, Zifan Carl Guo, Vincent Huang, Jacob Steinhardt, Jacob Andreas
Main category: cs.CL
TL;DR: LMs can learn to generate natural language explanations of their own internal computations, with self-explanation outperforming cross-model explanation even with more capable models.
Details
Motivation: To investigate whether language models can leverage their privileged access to internal computations to produce faithful explanations of their own behavior, complementing existing interpretability methods.Method: Fine-tune LMs using existing interpretability techniques as ground truth to generate natural language descriptions of: (1) information encoded by LM features, (2) causal structure of internal activations, and (3) influence of specific input tokens on outputs.
Result: Explainer models show non-trivial generalization to new queries with only tens of thousands of training examples. Self-explanation (model explaining itself) works better than cross-model explanation even when the explainer model is more capable.
Conclusion: LMs can learn to reliably explain their internal computations, offering a scalable complement to existing interpretability methods.
Abstract: Can language models (LMs) learn to faithfully describe their internal computations? Are they better able to describe themselves than other models? We study the extent to which LMs’ privileged access to their own internals can be leveraged to produce new techniques for explaining their behavior. Using existing interpretability techniques as a source of ground truth, we fine-tune LMs to generate natural language descriptions of (1) the information encoded by LM features, (2) the causal structure of LMs’ internal activations, and (3) the influence of specific input tokens on LM outputs. When trained with only tens of thousands of example explanations, explainer models exhibit non-trivial generalization to new queries. This generalization appears partly attributable to explainer models’ privileged access to their own internals: using a model to explain its own computations generally works better than using a different model to explain its computations (even if the explainer model is significantly more capable than the target). Our results suggest not only that LMs can learn to reliably explain their internal computations, but that such explanations offer a scalable complement to existing interpretability methods. Code and data at https://github.com/TransluceAI/introspective-interp
[153] Tracing Multilingual Representations in LLMs with Cross-Layer Transcoders
Abir Harrasse, Florent Draye, Punya Syon Pandey, Zhijing Jin, Bernhard Schölkopf
Main category: cs.CL
TL;DR: Multilingual LLMs form shared representations across languages with language-specific decoding in later layers, explaining performance gaps through feature analysis and interventions.
Details
Motivation: To understand how multilingual LLMs internally represent diverse languages and why performance favors dominant training languages, despite processing many languages.Method: Train models on different multilingual mixtures, analyze with Cross-Layer Transcoders (CLTs) and Attribution Graphs, perform Model-Diffing experiments, and test feature interventions.
Result: Multilingual shared representations exist with language-specific decoding in later layers; non-English failures stem from dim late-layer features, weak middle-layer clusters, and English-biased tokenizers; interventions can suppress/substitute languages.
Conclusion: Multilingual LLMs use shared representations with late-layer language-specific decoding; performance gaps arise from feature quality and tokenizer bias; finetuning improves multilingual capabilities.
Abstract: Multilingual Large Language Models (LLMs) can process many languages, yet how they internally represent this diversity remains unclear. Do they form shared multilingual representations with language-specific decoding, and if so, why does performance favor the dominant training language? To address this, we train models on different multilingual mixtures and analyze their internal mechanisms using Cross-Layer Transcoders (CLTs) and Attribution Graphs. Our results reveal multilingual shared representations: the model employs highly similar features across languages, while language-specific decoding emerges in later layers. Training models without English shows identical multilingual shared space structures. Decoding relies partly on a small set of high-frequency features in the final layers, which linearly encode language identity from early layers. Intervening on these features allows one language to be suppressed and another substituted. Finally, to explain non-English failures, we perform a Model-Diffing experiment: underperformance arises from dim late-layer features, weak middle-layer clusters, and tokenizer bias toward English that forces early layers to specialize in word reassembly. Finetuning strengthens these features and their links, improving token assembly and language-specific decoding, providing a mechanistic explanation for multilingual gaps. Our models and CLTs are available at https://huggingface.co/collections/CausalNLP/multilingual-clts and https://huggingface.co/collections/CausalNLP/multilingual-gpt2-models. Our code is available at: https://github.com/abirharrasse/MultilingualCLTs
[154] Predicting the Emergence of Induction Heads in Language Model Pretraining
Tatsuya Aoyama, Ethan Gotlieb Wilcox, Nathan Schneider
Main category: cs.CL
TL;DR: Study investigates factors influencing induction head formation in language models, focusing on training data statistical properties and their impact on in-context learning capabilities.
Details
Motivation: Induction heads are crucial for in-context learning in language models, but their emergence patterns aren't well understood. The paper aims to characterize how statistical properties of training data affect IH formation.Method: Analyzes IH formation in both natural and synthetic training data settings, examining relationships between data statistics (bigram repetition frequency, reliability) and model training parameters (batch size, context size).
Result: Found that: 1) Simple equation combining batch size and context size predicts IH formation point (agnostic to model size); 2) Bigram repetition frequency and reliability strongly affect IH formation with Pareto frontier; 3) Local dependency with high bigram stats is sufficient, but with low stats, categoricality and marginal distribution shape matter.
Conclusion: Provides systematic understanding of how training data statistics influence induction head formation, offering insights into in-context learning mechanisms and practical guidance for training data design.
Abstract: Specialized attention heads dubbed induction heads (IHs) have been argued to underlie the remarkable in-context learning capabilities of modern language models; yet, a precise characterization of their emergence, especially in the context of language modeling, remains wanting. In this study, we investigate the relationship between statistical properties of the training data and IH formation in both natural and synthetic training data settings. We show that: (1) A simple equation combining batch size and context size predicts the point at which IHs form and that this emergence point is agnostic to model size; (2) Surface bigram repetition frequency and reliability strongly affect the formation of IHs, and we find an effective Pareto frontier in terms of these two values; (3) local dependency with high bigram repetition frequency and reliability is sufficient for IH formation, but when the frequency and reliability are low, categoriality and the shape of the marginal distribution matter.
[155] ShoppingComp: Are LLMs Really Ready for Your Shopping Cart?
Huaixiao Tou, Ying Zeng, Yuemeng Li, Cong Ma, Muzhi Li, Minghao Li, Weijie Yuan, He Zhang, Kai Jia
Main category: cs.CL
TL;DR: ShoppingComp is a real-world benchmark for evaluating LLM-powered shopping agents on product retrieval, expert report generation, and safety-critical decision making, revealing significant limitations in current models.
Details
Motivation: Existing e-commerce benchmarks lack challenging real-world scenarios with open-world products and verifiable outputs. There's a need to evaluate shopping agents on core capabilities like precise product discovery with multiple constraints and safety-critical decision making.Method: Created a benchmark with 145 instances and 558 scenarios curated by 35 experts, featuring difficult product discovery queries with multiple constraints. The benchmark guarantees open-world products and enables easy verification of agent outputs.
Result: Current LLMs show stark limitations: GPT-5.2 achieved 17.76% and Gemini-3-Pro 15.82% performance. Error analysis revealed deficiencies in information grounding, multi-constraint verification, reasoning over noisy evidence, and risk-aware decision making.
Conclusion: ShoppingComp exposes critical capability gaps in LLM-powered shopping agents and characterizes the trust threshold AI systems must cross before being trusted for reliable real-world decision making.
Abstract: We present ShoppingComp, a challenging real-world benchmark for comprehensively evaluating LLM-powered shopping agents on three core capabilities: precise product retrieval, expert-level report generation, and safety critical decision making. Unlike prior e-commerce benchmarks, ShoppingComp introduces difficult product discovery queries with many constraints, while guaranteeing open-world products and enabling easy verification of agent outputs. The benchmark comprises 145 instances and 558 scenarios, curated by 35 experts to reflect authentic shopping needs. Results reveal stark limitations of current LLMs: even state-of-the-art models achieve low performance (e.g., 17.76% for GPT-5.2, 15.82% for Gemini-3-Pro).Error analysis reflects limitations in core agent competencies, including information grounding in open-world environments, reliable verification of multi-constraint requirements, consistent reasoning over noisy and conflicting evidence, and risk-aware decision making. By exposing these capability gaps, ShoppingComp characterizes the trust threshold that AI systems must cross before they can be proactively trusted for reliable real-world decision making. Our code and dataset are available at https://github.com/ByteDance-BandAI/ShoppingComp.
[156] Randomized Masked Finetuning: An Efficient Way to Mitigate Memorization of PIIs in LLMs
Kunj Joshi, Jaydeep Borkar, David A. Smith
Main category: cs.CL
TL;DR: RMFT is a privacy-preserving fine-tuning method that reduces PII memorization in LLMs by 80% while maintaining performance, outperforming deduplication techniques.
Details
Motivation: LLMs tend to memorize personally identifying information from training data, creating severe security and privacy risks that need to be addressed.Method: Randomized Masked Fine-Tuning (RMFT) - a novel privacy-preserving fine-tuning technique that reduces PII memorization while minimizing performance impact, evaluated using the Enron Email Dataset and MaxTER framework.
Result: RMFT achieves 80.81% reduction in Total Extraction Rate and 80.17% reduction in Seen Extraction Rate compared to baseline, with only 5.73% increase in perplexity, outperforming deduplication methods.
Conclusion: RMFT effectively addresses privacy concerns in LLMs by significantly reducing PII memorization while maintaining model utility, providing a better privacy-utility tradeoff than existing methods.
Abstract: The current literature on memorization in Natural Language Models, especially Large Language Models (LLMs), poses severe security and privacy risks, as models tend to memorize personally identifying information (PIIs) from training data. We introduce Randomized Masked Fine-Tuning (RMFT), a novel privacy-preserving fine-tuning technique that reduces PII memorization while minimizing performance impact. Using the Enron Email Dataset, we demonstrate that RMFT achieves an 80.81% reduction in Total Extraction Rate and 80.17% reduction in Seen Extraction Rate compared to baseline fine-tuning, outperforming deduplication methods while maintaining only a 5.73% increase in perplexity. We present MaxTER, a Pareto-optimal evaluation framework for assessing privacy-utility tradeoffs, and show the performance of RMFT vs Deduplication by Area Under The Response Curve (AURC) metric.
[157] Bolmo: Byteifying the Next Generation of Language Models
Benjamin Minixhofer, Tyler Murray, Tomasz Limisiewicz, Anna Korhonen, Luke Zettlemoyer, Noah A. Smith, Edoardo M. Ponti, Luca Soldaini, Valentin Hofmann
Main category: cs.CL
TL;DR: Bolmo introduces a family of open byte-level LLMs that approach subword-based model performance through a two-stage conversion process, enabling competitive performance while processing raw text encodings.
Details
Motivation: Subword tokenization obscures fine-grained character-level information crucial for scientific data like code and biological sequences. Byte-level models avoid these limitations but have historically lagged behind subword-based models in performance.Method: Two-stage conversion procedure: transform existing subword-based models into byte-level models with minimal additional training, enabling efficient processing of byte-level information while maintaining practical inference speeds.
Result: Bolmo models outperform prior byte-level approaches, excel on character-level reasoning tasks, remain competitive across standard benchmarks, and achieve practical inference speeds with low adaptation cost.
Conclusion: The research removes a long-standing performance barrier to end-to-end byte-level language modeling, demonstrating that byte-level models can scale competitively while offering advantages for domains requiring fine-grained textual understanding.
Abstract: Recent advances in generative AI have been largely driven by large language models (LLMs), deep neural networks that operate over discrete units called tokens. To represent text, the vast majority of LLMs use words or word fragments as the tokens, known as subword tokenization. Subword tokenization obscures fine-grained information, which is problematic, especially for scientific data - such as computer code or biological sequences - where meaning depends on the individual characters. Models that instead operate directly on the byte encoding of text avoid these limitations, but until now they have lagged behind subword-based models in performance. Here we introduce Bolmo, a family of fully open byte-level LLMs that approach the capabilities of subword-based systems. Using a two-stage conversion procedure, we transform existing subword-based models into byte-level models with minimal additional training. The resulting models outperform prior byte-level approaches and excel on character-level reasoning tasks, while remaining competitive across standard benchmarks. By efficiently processing byte-level information, these models achieve practical inference speeds and can be adapted at low cost using the existing ecosystem around the source LLM. Our results remove a long-standing performance barrier to end-to-end byte-level language modeling, demonstrating that models operating on raw text encodings can scale competitively while offering advantages in domains requiring fine-grained textual understanding.
[158] Accounting Reasoning in Large Language Models: Concepts, Evaluation, and Empirical Analysis
Jie Zhou, Xin Chen, Jie Zhang, Zhe Li
Main category: cs.CL
TL;DR: Evaluation of LLMs for accounting reasoning tasks shows GPT-4 performs best but current models remain insufficient for real-world accounting applications.
Details
Motivation: As LLMs become increasingly integrated into professional domains, there's a need to systematically understand their domain-specific reasoning capabilities, particularly in accounting where successful integration requires assessing their accounting reasoning abilities.Method: Proposed accounting reasoning concept and evaluation criteria based on GLM-series model training data analysis, then evaluated several LLMs (GLM-6B, GLM-130B, GLM-4, GPT-4) across accounting reasoning tasks with prompt engineering strategies.
Result: GPT-4 demonstrated the strongest overall accounting reasoning capability, prompt engineering improved performance across models, but current LLMs remain insufficient for real-world accounting applications.
Conclusion: Further optimization is needed for enterprise-level accounting deployment to fully realize LLMs’ potential value in the accounting domain.
Abstract: Large language models (LLMs) are increasingly reshaping learning paradigms, cognitive processes, and research methodologies across diverse domains. As their adoption expands, effectively integrating LLMs into professional fields and clarifying their role in domain-specific applications has become a key challenge for enterprise digital transformation and broader societal development. In the accounting domain, successful integration requires a systematic understanding of LLMs’ domain-specific reasoning capabilities. In this study, we introduce the concept of accounting reasoning and propose a set of evaluation criteria grounded in an analysis of the training data characteristics of representative GLM-series models. These criteria establish a foundation for studying accounting-oriented reasoning paradigms and provide benchmarks for assessing and improving model performance. Building on this framework, we evaluate several representative LLMs, including GLM-6B, GLM-130B, GLM-4, and GPT-4, across a range of accounting reasoning tasks. Our experimental results show that prompt engineering strategies can yield varying degrees of performance improvement across models, with GPT-4 demonstrating the strongest overall accounting reasoning capability. Nevertheless, the results indicate that current LLMs remain insufficient for real-world accounting applications. In particular, further optimization is required for deployment in enterprise-level accounting scenarios to fully realize the potential value of LLMs in this domain.
[159] Understanding Emotion in Discourse: Recognition Insights and Linguistic Patterns for Generation
Cheonkam Jeong, Adeline Nyamathi
Main category: cs.CL
TL;DR: Systematic study of Emotion Recognition in Conversation (ERC) on IEMOCAP reveals conversational context dominates performance, hierarchical representations help only without context, and affective lexicons don’t improve results. Linguistic analysis shows emotion-specific discourse marker patterns.
Details
Motivation: Two gaps in ERC research: lack of understanding of which modeling choices materially affect performance, and limited linguistic analysis linking recognition findings to actionable generation cues.Method: Systematic study on IEMOCAP with controlled ablations (10 random seeds, paired tests with correction). For recognition: tested conversational context window, hierarchical sentence representations, and external affective lexicon integration. For linguistic analysis: examined 5,286 discourse-marker occurrences.
Result: 1) Conversational context is dominant: 90% of gain achieved using only most recent 10-30 turns. 2) Hierarchical representations help utterance-only recognition but benefit vanishes with context. 3) Affective lexicon integration doesn’t improve results. 4) Sad utterances show reduced left-periphery marker usage (21.9% vs 28-32% for other emotions). 5) Sadness benefits most from conversational context (+22%p).
Conclusion: Conversational history subsumes intra-utterance structure, pretrained encoders already capture affective signal, and emotion-specific discourse patterns reveal sadness relies more on discourse history than overt pragmatic signaling.
Abstract: Despite strong recent progress in Emotion Recognition in Conversation (ERC), two gaps remain: we lack clear understanding of which modeling choices materially affect performance, and we have limited linguistic analysis linking recognition findings to actionable generation cues. We address both via a systematic study on IEMOCAP. For recognition, we conduct controlled ablations with 10 random seeds and paired tests (with correction for multiple comparisons), yielding three findings. First, conversational context is dominant: performance saturates quickly, with roughly 90% of gain achieved using only the most recent 10-30 preceding turns. Second, hierarchical sentence representations improve utterance-only recognition (K=0), but the benefit vanishes once turn-level context is available, suggesting conversational history subsumes intra-utterance structure. Third, external affective lexicon (SenticNet) integration does not improve results, consistent with pretrained encoders already capturing affective signal. Under strictly causal (past-only) setting, our simple models attain strong performance (82.69% 4-way; 67.07% 6-way weighted F1). For linguistic analysis, we examine 5,286 discourse-marker occurrences and find reliable association between emotion and marker position (p < 0.0001). Sad utterances show reduced left-periphery marker usage (21.9%) relative to other emotions (28-32%), aligning with accounts linking left-periphery markers to active discourse management. This pattern is consistent with Sad benefiting most from conversational context (+22%p), suggesting sadness relies more on discourse history than overt pragmatic signaling.
[160] VotIE: Information Extraction from Meeting Minutes
José Pedro Evans, Luís Filipe Cunha, Purificação Silvano, Alípio Jorge, Nuno Guimarães, Sérgio Nunes, Ricardo Campos
Main category: cs.CL
TL;DR: VotIE: A new information extraction task for identifying voting events in heterogeneous municipal meeting minutes, with benchmark on Portuguese municipal data showing fine-tuned encoders outperform generative models in-domain but LLMs generalize better across municipalities.
Details
Motivation: Municipal meeting minutes contain voting outcomes in highly heterogeneous, free-form narrative text that varies widely across municipalities, posing significant challenges for automated extraction compared to standardized parliamentary proceedings.Method: Introduces VotIE (Voting Information Extraction) task and establishes first benchmark using Portuguese municipal minutes from CitiLink corpus. Compares fine-tuned encoders (XLM-R-CRF) with generative approaches under both in-domain and cross-municipality evaluation settings.
Result: Fine-tuned encoders achieve 93.2% macro F1 in in-domain evaluation, outperforming generative approaches. In cross-municipality setting, fine-tuned models suffer substantial performance degradation while few-shot LLMs show greater robustness with smaller performance declines.
Conclusion: Lightweight fine-tuned encoders remain more practical for large-scale deployment despite LLMs’ generalization advantage due to computational cost constraints. Benchmark, models, and evaluation framework are publicly released for reproducible research.
Abstract: Municipal meeting minutes record key decisions in local democratic processes. Unlike parliamentary proceedings, which typically adhere to standardized formats, they encode voting outcomes in highly heterogeneous, free-form narrative text that varies widely across municipalities, posing significant challenges for automated extraction. In this paper, we introduce VotIE (Voting Information Extraction), a new information extraction task aimed at identifying structured voting events in narrative deliberative records, and establish the first benchmark for this task using Portuguese municipal minutes, building on the recently introduced CitiLink corpus. Our experiments yield two key findings. First, under standard in-domain evaluation, fine-tuned encoders, specifically XLM-R-CRF, achieve the strongest performance, reaching 93.2% macro F1, outperforming generative approaches. Second, in a cross-municipality setting that evaluates transfer to unseen administrative contexts, these models suffer substantial performance degradation, whereas few-shot LLMs demonstrate greater robustness, with significantly smaller declines in performance. Despite this generalization advantage, the high computational cost of generative models currently constrains their practicality. As a result, lightweight fine-tuned encoders remain a more practical option for large-scale, real-world deployment. To support reproducible research in administrative NLP, we publicly release our benchmark, trained models, and evaluation framework.
[161] SearchAttack: Red-Teaming LLMs against Knowledge-to-Action Threats under Online Web Search
Yu Yan, Sheng Sun, Mingfeng Li, Zheming Yang, Chiwei Zhu, Fei Ma, Benfeng Xu, Min Liu, Qi Li
Main category: cs.CL
TL;DR: SearchAttack: A red-teaming framework that exploits LLMs’ search capabilities to retrieve harmful content by rephrasing harmful queries with benign knowledge and leveraging reward-chasing bias, revealing vulnerabilities in search-augmented LLMs.
Details
Motivation: Addresses the reliability gap of LLMs in knowledge-intensive tasks and the risks of LLM-driven search being exploited for harmful content retrieval, particularly when search results contain ready-to-use harmful instructions that are difficult to undo once exposed.Method: Proposes SearchAttack with two key components: (1) rephrasing harmful semantics using dense benign knowledge to evade direct in-context decoding and elicit unsafe information retrieval, and (2) stress-testing LLMs’ reward-chasing bias by steering them to synthesize unsafe retrieved content. Also introduces a fact-checking framework to ground and quantify harm in offline/online settings.
Result: SearchAttack demonstrates strong effectiveness in attacking search-augmented LLMs. The study also finds that LLMs without web search can still be steered into harmful content output due to their information-seeking stereotypical behaviors.
Conclusion: Search-augmented LLMs have significant vulnerabilities that can be exploited to retrieve harmful content, highlighting the need for better safety mechanisms in LLM-driven search systems and responsible vulnerability assessment.
Abstract: Recently, people have suffered from LLM hallucination and have become increasingly aware of the reliability gap of LLMs in open and knowledge-intensive tasks. As a result, they have increasingly turned to search-augmented LLMs to mitigate this issue. However, LLM-driven search also becomes an attractive target for misuse. Once the returned content directly contains targeted, ready-to-use harmful instructions or takeaways for users, it becomes difficult to withdraw or undo such exposure. To investigate LLMs’ unsafe search behavior issues, we first propose \textbf{\textit{SearchAttack}} for red-teaming, which (1) rephrases harmful semantics via dense and benign knowledge to evade direct in-context decoding, thus eliciting unsafe information retrieval, (2) stress-tests LLMs’ reward-chasing bias by steering them to synthesize unsafe retrieved content. We also curate an emergent, domain-specific illicit activity benchmark for search-based threat assessment, and introduce a fact-checking framework to ground and quantify harm in both offline and online attack settings. Extensive experiments are conducted to red-team the search-augmented LLMs for responsible vulnerability assessment. Empirically, SearchAttack demonstrates strong effectiveness in attacking these systems. We also find that LLMs without web search can still be steered into harmful content output due to their information-seeking stereotypical behaviors.
[162] The Roots of Performance Disparity in Multilingual Language Models: Intrinsic Modeling Difficulty or Design Choices?
Chen Shani, Yuval Reif, Nathan Roll, Dan Jurafsky, Ekaterina Shutova
Main category: cs.CL
TL;DR: Survey paper analyzing why multilingual language models show uneven performance across languages, examining whether gaps stem from intrinsic linguistic difficulty or modeling artifacts like tokenization, encoding, and data allocation.
Details
Motivation: Current multilingual language models deliver uneven performance across the world's languages, and there's a need to understand whether these gaps reflect intrinsic linguistic difficulty or modeling artifacts to enable more equitable NLP systems.Method: Literature survey organized around two key questions: 1) whether linguistic disparities arise from representation and allocation choices rather than inherent complexity, and 2) which design choices mitigate inequities across typologically diverse languages.
Result: The survey finds that performance gaps often shrink when segmentation, encoding, and data exposure are normalized, suggesting much apparent difficulty stems from current modeling choices rather than inherent linguistic complexity.
Conclusion: The paper synthesizes insights into design recommendations for tokenization, sampling, architectures, and evaluation to support more balanced multilingual language models that perform equitably across diverse languages.
Abstract: Multilingual language models (LMs) promise broader NLP access, yet current systems deliver uneven performance across the world’s languages. This survey examines why these gaps persist and whether they reflect intrinsic linguistic difficulty or modeling artifacts. We organize the literature around two questions: do linguistic disparities arise from representation and allocation choices (e.g., tokenization, encoding, data exposure, parameter sharing) rather than inherent complexity; and which design choices mitigate inequities across typologically diverse languages. We review linguistic features, such as orthography, morphology, lexical diversity, syntax, information density, and typological distance, linking each to concrete modeling mechanisms. Gaps often shrink when segmentation, encoding, and data exposure are normalized, suggesting much apparent difficulty stems from current modeling choices. We synthesize these insights into design recommendations for tokenization, sampling, architectures, and evaluation to support more balanced multilingual LMs.
[163] From Rows to Reasoning: A Retrieval-Augmented Multimodal Framework for Spreadsheet Understanding
Anmol Gulati, Sahil Sen, Waqar Sarguroh, Kevin Paul
Main category: cs.CL
TL;DR: FRTR is a multimodal RAG framework for reasoning over complex enterprise spreadsheets with embedded visual content, achieving 74% accuracy on a new benchmark and reducing token usage by 50%.
Details
Motivation: LLMs struggle with large-scale enterprise spreadsheets containing thousands of numeric rows, multiple linked sheets, and embedded visual content like charts and receipts. Existing approaches using single-sheet compression or full-context encoding lack scalability and don't reflect real user interaction with complex multimodal workbooks.Method: FRTR decomposes Excel workbooks into granular row, column, and block embeddings, uses hybrid lexical-dense retrieval with Reciprocal Rank Fusion (RRF), and integrates multimodal embeddings to reason over both numerical and visual information.
Result: Achieved 74% answer accuracy on FRTR-Bench with Claude Sonnet 4.5 (vs 24% for prior SOTA), 87% accuracy on SpreadsheetLLM benchmark with GPT-5, while reducing token usage by roughly 50% compared to direct serialization methods.
Conclusion: FRTR provides an effective multimodal retrieval-augmented generation framework for reasoning over complex enterprise spreadsheets, significantly outperforming existing approaches while being more efficient.
Abstract: Large Language Models (LLMs) struggle to reason over large-scale enterprise spreadsheets containing thousands of numeric rows, multiple linked sheets, and embedded visual content such as charts and receipts. Prior state-of-the-art spreadsheet reasoning approaches typically rely on single-sheet compression or full-context encoding, which limits scalability and fails to reflect how real users interact with complex, multimodal workbooks. We introduce FRTR-Bench, the first large-scale benchmark for multimodal spreadsheet reasoning, comprising 30 enterprise-grade Excel workbooks spanning nearly four million cells and more than 50 embedded images. To address these challenges, we present From Rows to Reasoning (FRTR), an advanced, multimodal retrieval-augmented generation framework that decomposes Excel workbooks into granular row, column, and block embeddings, employs hybrid lexical-dense retrieval with Reciprocal Rank Fusion (RRF), and integrates multimodal embeddings to reason over both numerical and visual information. We tested FRTR on six LLMs, achieving 74% answer accuracy on FRTR-Bench with Claude Sonnet 4.5, a substantial improvement over prior state-of-the-art approaches that reached only 24%. On the SpreadsheetLLM benchmark, FRTR achieved 87% accuracy with GPT-5 while reducing token usage by roughly 50% compared to direct serialization methods.
[164] Evaluating Semantic and Syntactic Understanding in Large Language Models for Payroll Systems
Hendrika Maclean, Mert Can Cakmak, Muzakkiruddin Ahmed Mohammed, Shames Al Mandalawi, John Talburt
Main category: cs.CL
TL;DR: LLMs struggle with exact numerical calculations and auditability; payroll system evaluation shows regimes where prompting works vs. explicit computation needed
Details
Motivation: LLMs are widely used but unreliable for exact numerical calculations and producing auditable outputs, especially in high-stakes domains like payroll systemsMethod: Evaluated multiple LLM families (GPT, Claude, Perplexity, Grok, Gemini) on tiered payroll dataset with various prompting strategies from minimal baselines to schema-guided and reasoning variants
Result: Clear regimes identified: careful prompting sufficient in some cases, but explicit computation required for cent-accurate results in complex scenarios
Conclusion: Provides framework and practical guidance for deploying LLMs in accuracy-critical settings, highlighting limitations in numerical reasoning and auditability
Abstract: Large language models are now used daily for writing, search, and analysis, and their natural language understanding continues to improve. However, they remain unreliable on exact numerical calculation and on producing outputs that are straightforward to audit. We study synthetic payroll system as a focused, high-stakes example and evaluate whether models can understand a payroll schema, apply rules in the right order, and deliver cent-accurate results. Our experiments span a tiered dataset from basic to complex cases, a spectrum of prompts from minimal baselines to schema-guided and reasoning variants, and multiple model families including GPT, Claude, Perplexity, Grok and Gemini. Results indicate clear regimes where careful prompting is sufficient and regimes where explicit computation is required. The work offers a compact, reproducible framework and practical guidance for deploying LLMs in settings that demand both accuracy and assurance.
[165] CitiLink: Enhancing Municipal Transparency and Citizen Engagement through Searchable Meeting Minutes
Rodrigo Silva, José Evans, José Isidro, Miguel Marques, Afonso Fonseca, Ricardo Morais, João Canavilhas, Arian Pasquali, Purificação Silvano, Alípio Jorge, Nuno Guimarães, Sérgio Nunes, Ricardo Campos
Main category: cs.CL
TL;DR: CitiLink is an NLP platform that transforms unstructured municipal meeting minutes into structured, searchable data using LLMs for metadata extraction and BM25 ranking for search.
Details
Motivation: City council minutes are lengthy, formal documents with bureaucratic writing styles that make it difficult for citizens and journalists to efficiently find information, despite being publicly available. There's a need to enhance accessibility and transparency of local government through better information retrieval.Method: The system uses LLMs (specifically Gemini) to extract metadata, discussed subjects, and voting outcomes from unstructured minutes. The extracted structured data is indexed in a database supporting full-text search with BM25 ranking and faceted filtering through a user-friendly interface. Built over 120 minutes from six Portuguese municipalities.
Result: Developed a functional platform tested through guided sessions with municipal personnel, providing insights into real user interactions. Evaluated Gemini’s performance in extracting relevant information from minutes, highlighting its effectiveness in data extraction.
Conclusion: CitiLink demonstrates how NLP and IR techniques can enhance accessibility and transparency of local government by transforming unstructured municipal documents into structured, searchable data, with LLMs proving effective for information extraction from bureaucratic texts.
Abstract: City council minutes are typically lengthy and formal documents with a bureaucratic writing style. Although publicly available, their structure often makes it difficult for citizens or journalists to efficiently find information. In this demo, we present CitiLink, a platform designed to transform unstructured municipal meeting minutes into structured and searchable data, demonstrating how NLP and IR can enhance the accessibility and transparency of local government. The system employs LLMs to extract metadata, discussed subjects, and voting outcomes, which are then indexed in a database to support full-text search with BM25 ranking and faceted filtering through a user-friendly interface. The developed system was built over a collection of 120 minutes made available by six Portuguese municipalities. To assess its usability, CitiLink was tested through guided sessions with municipal personnel, providing insights into how real users interact with the system. In addition, we evaluated Gemini’s performance in extracting relevant information from the minutes, highlighting its effectiveness in data extraction.
[166] ClaimPT: A Portuguese Dataset of Annotated Claims in News Articles
Ricardo Campos, Raquel Sequeira, Sara Nerea, Inês Cantante, Diogo Folques, Luís Filipe Cunha, João Canavilhas, António Branco, Alípio Jorge, Sérgio Nunes, Nuno Guimarães, Purificação Silvano
Main category: cs.CL
TL;DR: ClaimPT: A new dataset of 1,308 European Portuguese news articles with 6,875 annotated factual claims, created through partnership with Portuguese News Agency LUSA, to advance fact-checking research in low-resource languages.
Details
Motivation: Fact-checking is slow and manual, unable to match misinformation spread online. While automation is needed, progress is uneven across languages - Portuguese lacks accessible datasets, limiting research and applications. Most existing resources focus on social media or parliamentary transcripts, not journalistic content.Method: Created ClaimPT dataset through partnership with LUSA (Portuguese News Agency), focusing on journalistic content. Used two trained annotators per article with curator validation. Developed new annotation scheme and provided baseline models for claim detection.
Result: Produced dataset of 1,308 European Portuguese news articles with 6,875 individual annotations. Established initial benchmarks for claim detection in Portuguese, enabling future NLP and information retrieval applications.
Conclusion: ClaimPT addresses the lack of Portuguese fact-checking resources, advances low-resource language research, and enhances understanding of misinformation in news media by providing a quality dataset with journalistic focus.
Abstract: Fact-checking remains a demanding and time-consuming task, still largely dependent on manual verification and unable to match the rapid spread of misinformation online. This is particularly important because debunking false information typically takes longer to reach consumers than the misinformation itself; accelerating corrections through automation can therefore help counter it more effectively. Although many organizations perform manual fact-checking, this approach is difficult to scale given the growing volume of digital content. These limitations have motivated interest in automating fact-checking, where identifying claims is a crucial first step. However, progress has been uneven across languages, with English dominating due to abundant annotated data. Portuguese, like other languages, still lacks accessible, licensed datasets, limiting research, NLP developments and applications. In this paper, we introduce ClaimPT, a dataset of European Portuguese news articles annotated for factual claims, comprising 1,308 articles and 6,875 individual annotations. Unlike most existing resources based on social media or parliamentary transcripts, ClaimPT focuses on journalistic content, collected through a partnership with LUSA, the Portuguese News Agency. To ensure annotation quality, two trained annotators labeled each article, with a curator validating all annotations according to a newly proposed scheme. We also provide baseline models for claim detection, establishing initial benchmarks and enabling future NLP and IR applications. By releasing ClaimPT, we aim to advance research on low-resource fact-checking and enhance understanding of misinformation in news media.
[167] NRR-Phi: Text-to-State Mapping for Ambiguity Preservation in LLM Inference
Kei Saito
Main category: cs.CL
TL;DR: A framework for text-to-state mapping that preserves multiple interpretations of ambiguous language, preventing LLMs from prematurely committing to single meanings.
Details
Motivation: Addresses LLMs' tendency toward early semantic commitment where they collapse multiple valid interpretations of ambiguous input into a single response before sufficient context is available.Method: Formal text-to-state mapping framework with three stages: conflict detection, interpretation extraction, and state construction. Uses hybrid extraction pipeline combining rule-based segmentation for explicit conflict markers with LLM-based enumeration of implicit ambiguity.
Result: On 68 ambiguous sentences, the framework preserves interpretive multiplicity with mean state entropy H = 1.087 bits across ambiguity categories, compared to H = 0 for collapse-based baselines. Also demonstrated cross-lingual portability for Japanese markers.
Conclusion: Provides algorithmic bridge between text and Non-Resolution Reasoning state space, enabling architectural collapse deferment in LLM inference with design principles validated on 580 test cases.
Abstract: Large language models exhibit a systematic tendency toward early semantic commitment: given ambiguous input, they collapse multiple valid interpretations into a single response before sufficient context is available. We present a formal framework for text-to-state mapping ($φ: \mathcal{T} \to \mathcal{S}$) that transforms natural language into a non-collapsing state space where multiple interpretations coexist. The mapping decomposes into three stages: conflict detection, interpretation extraction, and state construction. We instantiate $φ$ with a hybrid extraction pipeline combining rule-based segmentation for explicit conflict markers (adversative conjunctions, hedging expressions) with LLM-based enumeration of implicit ambiguity (epistemic, lexical, structural). On a test set of 68 ambiguous sentences, the resulting states preserve interpretive multiplicity: mean state entropy $H = 1.087$ bits across ambiguity categories, compared to $H = 0$ for collapse-based baselines. We additionally instantiate the rule-based conflict detector for Japanese markers to illustrate cross-lingual portability. This framework extends Non-Resolution Reasoning (NRR) by providing the missing algorithmic bridge between text and the NRR state space, enabling architectural collapse deferment in LLM inference. Design principles for state-to-state transformations are detailed in the Appendix, with empirical validation on 580 test cases showing 0% collapse for principle-satisfying operators versus up to 17.8% for violating operators.
[168] Large Language Model Agents Are Not Always Faithful Self-Evolvers
Weixiang Zhao, Yingshuo Wang, Yichen Zhang, Yang Deng, Yanyan Zhao, Wanxiang Che, Bing Qin, Ting Liu
Main category: cs.CL
TL;DR: Systematic investigation reveals self-evolving LLM agents often fail to faithfully use condensed experience, despite relying on raw experience, due to semantic limitations, processing biases, and task regimes where pretrained knowledge suffices.
Details
Motivation: While self-evolving LLM agents improve by accumulating past experience, it's unclear whether they actually rely on that experience to guide their behavior. The paper aims to investigate "experience faithfulness" - the causal dependence of an agent's decisions on the experience it is given.Method: Used controlled causal interventions on both raw and condensed forms of experience. Evaluated four representative frameworks across 10 LLM backbones and 9 environments. Analyzed single- and multi-agent configurations across different backbone scales.
Result: Found a striking asymmetry: agents consistently depend on raw experience but often disregard or misinterpret condensed experience, even when it’s the only experience provided. This gap persists across configurations and scales. Identified three underlying causes: semantic limitations of condensed content, internal processing biases that suppress experience, and task regimes where pretrained priors already suffice.
Conclusion: These findings challenge prevailing assumptions about self-evolving methods and underscore the need for more faithful and reliable approaches to experience integration in LLM agents.
Abstract: Self-evolving large language model (LLM) agents continually improve by accumulating and reusing past experience, yet it remains unclear whether they faithfully rely on that experience to guide their behavior. We present the first systematic investigation of experience faithfulness, the causal dependence of an agent’s decisions on the experience it is given, in self-evolving LLM agents. Using controlled causal interventions on both raw and condensed forms of experience, we comprehensively evaluate four representative frameworks across 10 LLM backbones and 9 environments. Our analysis uncovers a striking asymmetry: while agents consistently depend on raw experience, they often disregard or misinterpret condensed experience, even when it is the only experience provided. This gap persists across single- and multi-agent configurations and across backbone scales. We trace its underlying causes to three factors: the semantic limitations of condensed content, internal processing biases that suppress experience, and task regimes where pretrained priors already suffice. These findings challenge prevailing assumptions about self-evolving methods and underscore the need for more faithful and reliable approaches to experience integration.
[169] $ρ$-$\texttt{EOS}$: Training-free Bidirectional Variable-Length Control for Masked Diffusion LLMs
Jingyi Yang, Yuxian Jiang, Jing Shao
Main category: cs.CL
TL;DR: A training-free method called ρ-EOS enables bidirectional variable-length generation for masked diffusion LLMs by using implicit EOS token density as a signal to adjust generation length during denoising.
Details
Motivation: Current masked diffusion LLMs require predefined fixed generation lengths, creating a trade-off between output quality and computational efficiency. The authors aim to enable flexible, variable-length generation without compromising performance.Method: The method analyzes denoising dynamics and finds that implicit EOS token density indicates generation sufficiency. ρ-EOS uses this density signal to bidirectionally adjust length during denoising: high density triggers mask token contraction, low density induces expansion, all within a single unified process.
Result: Experiments on mathematics and code benchmarks show ρ-EOS achieves comparable performance while substantially improving inference efficiency and token utilization compared to fixed-length approaches.
Conclusion: ρ-EOS provides an effective training-free solution for variable-length generation in masked diffusion LLMs, addressing the fundamental limitation of fixed generation lengths while maintaining performance and improving efficiency.
Abstract: Beyond parallel generation and global context modeling, current masked diffusion large language models (masked dLLMs, i.e., LLaDA) suffer from a fundamental limitation: they require a predefined, fixed generation length, which lacks flexibility and forces an inevitable trade-off between output quality and computational efficiency. To address this, we study the denoising dynamics and find that the implicit density ($ρ$) of end-of-sequence ($\texttt{EOS}$) tokens serves as a reliable signal of generation sufficiency. In particular, the evolving implicit $\texttt{EOS}$ density during denoising reveals whether the current masked space is excessive or insufficient, thereby guiding the adjustment direction for generation length. Building on this insight, we propose $\textbf{$ρ$-$\texttt{EOS}$}$, a training-free, single-stage strategy that enables bidirectional variable-length generation for masked dLLMs. Unlike prior two-stage approaches–which require separate length adjustment and iterative mask insertion phases while supporting only unidirectional expansion–$\textbf{$ρ$-$\texttt{EOS}$}$ achieves bidirectional length adjustment within a unified denoising process by continuously estimating the implicit $\texttt{EOS}$ density: excessively high density triggers $\texttt{MASK}$ token contraction, while insufficient density induces expansion. Extensive experiments on mathematics and code benchmarks demonstrate that $\textbf{$ρ$-$\texttt{EOS}$}$ achieves comparable performance while substantially improving inference efficiency and token utilization. Code is available at https://github.com/yjyddq/rho-EOS.
[170] MiNER: A Two-Stage Pipeline for Metadata Extraction from Municipal Meeting Minutes
Rodrigo Batista, Luís Filipe Cunha, Purificação Silvano, Nuno Guimarães, Alípio Jorge, Evelin Amorim, Ricardo Campos
Main category: cs.CL
TL;DR: Two-stage pipeline for extracting metadata from municipal meeting minutes using QA to locate metadata sections followed by transformer models for entity extraction, benchmarked against LLMs.
Details
Motivation: Municipal meeting minutes have heterogeneous formats and lack standardized metadata extraction methods, requiring domain-specific approaches beyond general NER models.Method: Two-stage pipeline: 1) QA model identifies opening/closing segments containing metadata, 2) Transformer models (BERTimbau, XLM-RoBERTa ± CRF layer) perform fine-grained entity extraction with deslexicalization enhancement.
Result: Strong in-domain performance outperforming larger general-purpose LLMs, but reduced cross-municipality generalization due to variability and linguistic complexity of municipal records.
Conclusion: Establishes first benchmark for metadata extraction from municipal minutes, providing foundation for future research in this domain-specific information extraction task.
Abstract: Municipal meeting minutes are official documents of local governance, exhibiting heterogeneous formats and writing styles. Effective information retrieval (IR) requires identifying metadata such as meeting number, date, location, participants, and start/end times, elements that are rarely standardized or easy to extract automatically. Existing named entity recognition (NER) models are ill-suited to this task, as they are not adapted to such domain-specific categories. In this paper, we propose a two-stage pipeline for metadata extraction from municipal minutes. First, a question answering (QA) model identifies the opening and closing text segments containing metadata. Transformer-based models (BERTimbau and XLM-RoBERTa with and without a CRF layer) are then applied for fine-grained entity extraction and enhanced through deslexicalization. To evaluate our proposed pipeline, we benchmark both open-weight (Phi) and closed-weight (Gemini) LLMs, assessing predictive performance, inference cost, and carbon footprint. Our results demonstrate strong in-domain performance, better than larger general-purpose LLMs. However, cross-municipality evaluation reveals reduced generalization reflecting the variability and linguistic complexity of municipal records. This work establishes the first benchmark for metadata extraction from municipal meeting minutes, providing a solid foundation for future research in this domain.
[171] Clause-Internal or Clause-External? Testing Turkish Reflexive Binding in Adapted versus Chain of Thought Large Language Models
Sercan Karakaş
Main category: cs.CL
TL;DR: Evaluation of Turkish reflexive pronoun binding in two LLMs shows Trendyol-LLM has strong locality bias (70% local antecedents) while OpenAI model shows balanced distribution, revealing architectural/training differences in anaphoric dependency representation.
Details
Motivation: To assess whether state-of-the-art large language models properly capture the binding relations of Turkish reflexive pronouns, specifically examining how they handle local vs. non-local antecedents for reflexives kendi and kendisi.Method: Constructed balanced evaluation set of 100 Turkish sentences systematically pitting local against non-local antecedents. Compared OpenAI chain-of-thought model (optimized for multi-step reasoning) with Trendyol-LLM-7B-base-v0.1 (LLaMA 2 derived model fine-tuned on Turkish data). Used combined paradigm integrating sentence-level perplexity with forced-choice comparison between minimally differing continuations.
Result: Trendyol-LLM favors local bindings in ~70% of trials, showing robust locality bias consistent with preference for structurally proximate antecedents. OpenAI model (o1 Mini) distributes choices nearly evenly between local and long-distance readings, suggesting weaker/less consistent sensitivity to locality in this binding configuration.
Conclusion: Results reveal marked contrast in binding behavior across the two systems, motivating closer analysis of how model architecture, training data, and inference-time reasoning strategies shape representation of Turkish anaphoric dependencies.
Abstract: This study evaluates whether state-of-the-art large language models capture the binding relations of Turkish reflexive pronouns. We construct a balanced evaluation set of 100 Turkish sentences that systematically pit local against non-local antecedents for the reflexives kendi and kendisi. We compare two contrasting systems: an OpenAI chain-of-thought model optimized for multi-step reasoning and Trendyol-LLM-7B-base-v0.1, a LLaMA 2 derived model extensively fine-tuned on Turkish data. Antecedent choice is assessed using a combined paradigm that integrates sentence-level perplexity with a forced-choice comparison between minimally differing continuations. Overall, Trendyol-LLM favors local bindings in approximately 70 percent of trials, exhibiting a robust locality bias consistent with a preference for structurally proximate antecedents. By contrast, the OpenAI model (o1 Mini) distributes its choices nearly evenly between local and long-distance readings, suggesting weaker or less consistent sensitivity to locality in this binding configuration. Taken together, these results reveal a marked contrast in binding behavior across the two systems and motivate closer analysis of how model architecture, training data, and inference-time reasoning strategies shape the representation of Turkish anaphoric dependencies.
[172] Lookahead-then-Verify: Reliable Constrained Decoding for Diffusion LLMs under Context-Free Grammars
Yitong Zhang, Yongmin Li, Yuetong Liu, Jia Li, Xiaoran Jia, Zherui Li, Ge Li
Main category: cs.CL
TL;DR: LAVE is a constrained decoding approach for diffusion-based LLMs that uses parallel token distribution predictions to perform lookahead verification, ensuring grammatical correctness while maintaining efficiency.
Details
Motivation: Diffusion LLMs struggle with reliably generating syntactically valid outputs for formal languages like source code and chemical expressions. Existing constrained decoding techniques don't work well with non-autoregressive dLLMs, and current dLLM-specific approaches allow intermediate outputs that can't be completed into valid sentences.Method: LAVE leverages dLLMs’ ability to predict token distributions for all positions in parallel. When a new token is proposed, it performs lookahead using these distributions to efficiently verify token validity, ensuring intermediate outputs can always be extended into valid sentences.
Result: Extensive experiments across four dLLMs and three benchmarks show LAVE consistently outperforms existing baselines, achieving substantial improvements in syntactic correctness with negligible runtime overhead.
Conclusion: LAVE provides an effective constrained decoding approach for dLLMs that reliably enforces grammatical constraints while maintaining efficiency, addressing key limitations of current methods for non-autoregressive language models.
Abstract: Diffusion Large Language Models (dLLMs) have demonstrated promising generative capabilities and are increasingly used to produce formal languages defined by context-free grammars, such as source code and chemical expressions. However, as probabilistic models, they still struggle to generate syntactically valid outputs reliably. A natural and promising direction to address this issue is to adapt constrained decoding techniques to enforce grammatical correctness during generation. However, applying these techniques faces two primary obstacles. On the one hand, the non-autoregressive nature of dLLMs renders most existing constrained decoding approaches inapplicable. On the other hand, current approaches specifically designed for dLLMs may allow intermediate outputs that are impossible to complete into valid sentences, which significantly limits their reliability in practice. To address these challenges, we present LAVE, a constrained decoding approach specifically designed for dLLMs. Our approach leverages a key property of dLLMs, namely their ability to predict token distributions for all positions in parallel during each forward pass. Whenever a new token is proposed by model, LAVE performs lookahead using these distributions to efficiently and reliably verify the validity of the proposed token. This design ensures reliable constraints by reliably preserving the potential for intermediate outputs to be extended into valid sentences. Extensive experiments across four widely used dLLMs and three representative benchmarks demonstrate that LAVE consistently outperforms existing baselines and achieves substantial improvements in syntactic correctness, while incurring negligible runtime overhead.
[173] APR: Penalizing Structural Redundancy in Large Reasoning Models via Anchor-based Process Rewards
Kaiyan Chang, Chenwei Zhu, Yingfeng Luo, Yifu Huo, Chenglong Wang, Xiaoqian Liu, Qiaozhi He, Tong Xiao, Zhengtao Yu, Jingbo Zhu
Main category: cs.CL
TL;DR: Test-Time Scaling improves Large Reasoning Models but causes Overthinking - repetitive self-verification after obtaining final answers. The paper identifies Reasoning Anchor (where answer first stabilizes) and Answer-Stable Tail (meaningless post-anchor verification), proposing Anchor-based Process Reward to penalize only the redundant tail.
Details
Motivation: Test-Time Scaling enhances Large Reasoning Models but introduces Overthinking - models continue repetitive self-verification even after obtaining correct answers, wasting computational resources. The authors aim to understand this phenomenon and develop efficient methods to eliminate redundant reasoning while maintaining performance.Method: The authors identify Reasoning Anchor (position where answer first stabilizes) and Answer-Stable Tail (repetitive verification after anchor). They propose Anchor-based Process Reward (APR), a structure-aware reward shaping method that localizes reasoning anchor and penalizes only the post-anchor AST using policy optimization algorithms suitable for length penalties.
Result: APR models achieved performance-efficiency Pareto frontier at 1.5B and 7B scales across five mathematical reasoning datasets while requiring substantially fewer computational resources for RL training compared to baseline methods.
Conclusion: The paper provides a fine-grained understanding of Overthinking in Large Reasoning Models, identifies structural redundancy (Answer-Stable Tail), and proposes an efficient solution (Anchor-based Process Reward) that eliminates wasteful computation while maintaining model performance.
Abstract: Test-Time Scaling (TTS) has significantly enhanced the capabilities of Large Reasoning Models (LRMs) but introduces a critical side-effect known as Overthinking. We conduct a preliminary study to rethink this phenomenon from a fine-grained perspective. We observe that LRMs frequently conduct repetitive self-verification without revision even after obtaining the final answer during the reasoning process. We formally define this specific position where the answer first stabilizes as the Reasoning Anchor. By analyzing pre- and post-anchor reasoning behaviors, we uncover the structural redundancy fixed in LRMs: the meaningless repetitive verification after deriving the first complete answer, which we term the Answer-Stable Tail (AST). Motivated by this observation, we propose Anchor-based Process Reward (APR), a structure-aware reward shaping method that localizes the reasoning anchor and penalizes exclusively the post-anchor AST. Leveraging the policy optimization algorithm suitable for length penalties, our APR models achieved the performance-efficiency Pareto frontier at 1.5B and 7B scales averaged across five mathematical reasoning datasets while requiring substantially fewer computational resources for RL training.
[174] Supervised Fine-Tuning Needs to Unlock the Potential of Token Priority
Zhanming Shen, Zeyu Qin, Jiaqi Hu, Wentao Ye, Hao Chen, Xiaomeng Hu, Haokai Xu, Gang Chen, Yi R. Fung, Haobo Wang
Main category: cs.CL
TL;DR: Position paper advocating Token Priority as a framework to bridge the granularity mismatch between fine-grained autoregressive generation and coarse supervision signals in alignment research.
Details
Motivation: The paper addresses a fundamental constraint in AI alignment: the mismatch between fine-grained autoregressive generation (token-by-token) and coarse/uniform supervision signals, which limits progress from empirical data fitting to achieving true human utility.Method: Proposes Token Priority as a unifying framework, formalizing Supervised Fine-Tuning (SFT) as a distribution reshaping process rather than simple optimization. Categorizes existing approaches into two regimes: Positive Priority (noise filtration) and Signed Priority (toxic modes unlearning).
Result: Provides a unified lens to analyze recent breakthroughs in alignment research, revisits existing progress and limitations, identifies key challenges, and suggests future research directions.
Conclusion: Token Priority is essential for bridging the granularity mismatch in AI alignment, offering a framework to systematically reshape distributions to align with ideal alignment manifolds rather than just optimizing for coarse signals.
Abstract: The transition from fitting empirical data to achieving true human utility is fundamentally constrained by a granularity mismatch, where fine-grained autoregressive generation is often supervised by coarse or uniform signals. This position paper advocates Token Priority as the essential bridge, formalizing Supervised Fine-Tuning (SFT) not as simple optimization but as a precise distribution reshaping process that aligns raw data with the ideal alignment manifold. We analyze recent breakthroughs through this unified lens, categorizing them into two distinct regimes: Positive Priority for noise filtration and Signed Priority for toxic modes unlearning. We revisit existing progress and limitations, identify key challenges, and suggest directions for future research.
[175] From Pragmas to Partners: A Symbiotic Evolution of Agentic High-Level Synthesis
Niansong Zhang, Sunwoo Kim, Shreesha Srinath, Zhiru Zhang
Main category: cs.CL
TL;DR: HLS remains essential in AI-driven hardware design era, serving as practical abstraction layer for agentic optimization with faster iteration, portability, and design permutability.
Details
Motivation: To address whether high-level synthesis (HLS) still matters in the agentic era of AI-driven hardware design, arguing that HLS remains essential despite the rise of large language models and AI agents.Method: Position paper analyzing HLS’s role in agentic hardware design through three contributions: explaining HLS as practical abstraction layer, identifying current HLS tool limitations that agents can address, and proposing taxonomy for symbiotic evolution of agentic HLS.
Result: Establishes HLS as crucial layer for agentic optimization with faster iteration cycles, portability, and design permutability, while identifying key limitations in current HLS tools that AI agents are uniquely positioned to overcome.
Conclusion: HLS remains essential in the agentic era, serving as golden reference for AI-driven hardware design, with proposed taxonomy showing how responsibility shifts from humans to AI agents as systems evolve from copilots to autonomous design partners.
Abstract: The rise of large language models has sparked interest in AI-driven hardware design, raising the question: does high-level synthesis (HLS) still matter in the agentic era? We argue that HLS remains essential. While we expect mature agentic hardware systems to leverage both HLS and RTL, this paper focuses on HLS and its role in enabling agentic optimization. HLS offers faster iteration cycles, portability, and design permutability that make it a natural layer for agentic optimization. This position paper makes three contributions. First, we explain why HLS serves as a practical abstraction layer and a golden reference for agentic hardware design. Second, we identify key limitations of current HLS tools, namely inadequate performance feedback, rigid interfaces, and limited debuggability that agents are uniquely positioned to address. Third, we propose a taxonomy for the symbiotic evolution of agentic HLS, clarifying how responsibility shifts from human designers to AI agents as systems advance from copilots to autonomous design partners.
[176] Out of the Memory Barrier: A Highly Memory Efficient Training System for LLMs with Million-Token Contexts
Wenhao Li, Daohai Yu, Gen Luo, Yuxin Zhang, Fei Chao, Rongrong Ji, Yifan Wu, Jiaxin Liu, Ziyang Gong, Zimu Liao
Main category: cs.CL
TL;DR: OOMB is a memory-efficient training system for LLMs that enables training with extremely long contexts (up to 4M tokens) on a single GPU by using chunk-recurrent training with constant activation memory and optimized KV cache management.
Details
Motivation: Training LLMs on long contexts is limited by prohibitive GPU memory overhead from activations that scale linearly with sequence length, requiring large clusters with context parallelism.Method: Uses chunk-recurrent training framework with on-the-fly activation recomputation for constant activation memory, plus paged memory manager for KV cache, asynchronous CPU offloading, and page-level sparse attention to manage KV cache growth.
Result: Achieves only 10MB memory increase per 10K additional tokens for Qwen2.5-7B, enabling 4M-token context training on a single H200 GPU instead of requiring large clusters.
Conclusion: OOMB represents a substantial advance in resource efficiency for long-context LLM training, making long-context training accessible on single GPUs.
Abstract: Training Large Language Models (LLMs) on long contexts is severely constrained by prohibitive GPU memory overhead, not training time. The primary culprits are the activations, whose memory footprints scale linearly with sequence length. We introduce OOMB, a highly memory-efficient training system that directly confronts this barrier. Our approach employs a chunk-recurrent training framework with on-the-fly activation recomputation, which maintains a constant activation memory footprint (O(1)) and shifts the primary bottleneck to the growing KV cache. To manage the KV cache, OOMB integrates a suite of synergistic optimizations: a paged memory manager for both the KV cache and its gradients to eliminate fragmentation, asynchronous CPU offloading to hide data transfer latency, and page-level sparse attention to reduce both computational complexity and communication overhead. The synergy of these techniques yields exceptional efficiency. Our empirical results show that for every additional 10K tokens of context, the end-to-end training memory overhead increases by a mere 10MB for Qwen2.5-7B. This allows training Qwen2.5-7B with a 4M-token context on a single H200 GPU, a feat that would otherwise require a large cluster using context parallelism. This work represents a substantial advance in resource efficiency for long-context LLM training. The source code is available at https://github.com/wenhaoli-xmu/OOMB.
[177] Which course? Discourse! Teaching Discourse and Generation in the Era of LLMs
Junyi Jessy Li, Yang Janet Liu, Kanishka Misra, Valentina Pyatkin, William Sheffield
Main category: cs.CL
TL;DR: A paper describing a new undergraduate course “Computational Discourse and Natural Language Generation” that integrates discourse processing theory with NLP education, addressing curriculum design challenges in a rapidly evolving field.
Details
Motivation: The rapid evolution of NLP creates educational challenges in designing courses that bridge sub-disciplines. Discourse processing offers rich linguistic insights and computational models relevant to text generation, but this connection is under-explored in existing curricula.Method: The authors designed and offered a new upper-level undergraduate course cross-listed between Linguistics and Computer Science. The course integrates theoretical and empirical aspects of discourse processing with natural language generation, using collaborative design by experts with complementary expertise.
Result: The course was successfully offered in Fall 2025. An independent survey provided positive feedback and takeaways. The course design philosophy emphasizes deep integration of theory and practice, creating an exploratory mindset in classroom activities and assignments.
Conclusion: The paper presents a successful model for integrating discourse processing with NLP education, addressing curriculum gaps in a rapidly evolving field. The authors share their vision for future directions in NLP education that bridge theoretical linguistics with computational approaches.
Abstract: The field of NLP has undergone vast, continuous transformations over the past few years, sparking debates going beyond discipline boundaries. This begs important questions in education: how do we design courses that bridge sub-disciplines in this shifting landscape? This paper explores this question from the angle of discourse processing, an area with rich linguistic insights and computational models for the intentional, attentional, and coherence structure of language. Discourse is highly relevant for open-ended or long-form text generation, yet this connection is under-explored in existing undergraduate curricula. We present a new course, “Computational Discourse and Natural Language Generation”. The course is collaboratively designed by a team with complementary expertise and was offered for the first time in Fall 2025 as an upper-level undergraduate course, cross-listed between Linguistics and Computer Science. Our philosophy is to deeply integrate the theoretical and empirical aspects, and create an exploratory mindset inside the classroom and in the assignments. This paper describes the course in detail and concludes with takeaways from an independent survey as well as our vision for future directions.
[178] ReFRAME or Remain: Unsupervised Lexical Semantic Change Detection with Frame Semantics
Bach Phan-Tat, Kris Heylen, Dirk Geeraerts, Stefano De Pascale, Dirk Speelman
Main category: cs.CL
TL;DR: Frame semantics approach for lexical semantic change detection that outperforms neural embedding methods while providing better interpretability
Details
Motivation: Current neural embedding methods for lexical semantic change detection perform well but lack interpretability, making their results difficult to understand and trustMethod: Uses frame semantics instead of distributional representations, relying on semantic frames to detect changes in word meanings over time
Result: The frame semantics method is effective for detecting semantic change and can outperform many distributional semantic models
Conclusion: Frame semantics provides a viable alternative to neural embeddings for LSC detection, offering both strong performance and high interpretability
Abstract: The majority of contemporary computational methods for lexical semantic change (LSC) detection are based on neural embedding distributional representations. Although these models perform well on LSC benchmarks, their results are often difficult to interpret. We explore an alternative approach that relies solely on frame semantics. We show that this method is effective for detecting semantic change and can even outperform many distributional semantic models. Finally, we present a detailed quantitative and qualitative analysis of its predictions, demonstrating that they are both plausible and highly interpretable
[179] BioACE: An Automated Framework for Biomedical Answer and Citation Evaluations
Deepak Gupta, Davis Bartels, Dina Demner-Fushman
Main category: cs.CL
TL;DR: BioACE: An automated framework for evaluating biomedical answers and citations generated by LLMs, assessing completeness, correctness, precision, and recall against ground-truth facts.
Details
Motivation: With increasing use of LLMs for biomedical question answering, there's a need for automated evaluation of answer quality and citation support, as manual expert assessment is time-consuming and expensive.Method: Proposes BioACE framework with automated approaches to evaluate answer completeness, correctness, precision, and recall against ground-truth nuggets. Also evaluates citation quality using NLI, pre-trained language models, and LLMs.
Result: Extensive experiments show correlation with human evaluations. Provides best approaches for biomedical answer and citation evaluation as part of open-source BioACE package.
Conclusion: BioACE offers an effective automated framework for evaluating biomedical answers and citations from LLMs, addressing the challenge of expert assessment in biomedical NLP tasks.
Abstract: With the increasing use of large language models (LLMs) for generating answers to biomedical questions, it is crucial to evaluate the quality of the generated answers and the references provided to support the facts in the generated answers. Evaluation of text generated by LLMs remains a challenge for question answering, retrieval-augmented generation (RAG), summarization, and many other natural language processing tasks in the biomedical domain, due to the requirements of expert assessment to verify consistency with the scientific literature and complex medical terminology. In this work, we propose BioACE, an automated framework for evaluating biomedical answers and citations against the facts stated in the answers. The proposed BioACE framework considers multiple aspects, including completeness, correctness, precision, and recall, in relation to the ground-truth nuggets for answer evaluation. We developed automated approaches to evaluate each of the aforementioned aspects and performed extensive experiments to assess and analyze their correlation with human evaluations. In addition, we considered multiple existing approaches, such as natural language inference (NLI) and pre-trained language models and LLMs, to evaluate the quality of evidence provided to support the generated answers in the form of citations into biomedical literature. With the detailed experiments and analysis, we provide the best approaches for biomedical answer and citation evaluation as a part of BioACE (https://github.com/deepaknlp/BioACE) evaluation package.
[180] OPUS: Towards Efficient and Principled Data Selection in Large Language Model Pre-training in Every Iteration
Shaobo Wang, Xuan Ouyang, Tianyi Xu, Yuzheng Hu, Jialin Liu, Guo Chen, Tianyu Zhang, Junhao Zheng, Kexin Yang, Xingzhang Ren, Dayiheng Liu, Linfeng Zhang
Main category: cs.CL
TL;DR: OPUS is a dynamic data selection framework that selects training data based on optimizer-induced projected utility, achieving superior efficiency over static filters and full training.
Details
Motivation: As high-quality public text data becomes exhausted (Data Wall), pre-training needs to shift from more tokens to better tokens. Existing methods use either heuristic static filters that ignore training dynamics, or dynamic but optimizer-agnostic criteria based on raw gradients.Method: OPUS defines utility in the optimizer-induced update space, scoring candidates by projecting their effective updates (shaped by modern optimizers) onto a target direction from a stable, in-distribution proxy. Uses Ghost technique with CountSketch for computational efficiency and Boltzmann sampling for data diversity.
Result: Achieves remarkable results across diverse corpora, quality tiers, optimizers, and model scales. In GPT-2 Large/XL pre-training on FineWeb with 30B tokens, outperforms industrial baselines and even full 200B-token training. With Qwen3-8B-Base on SciencePedia, achieves superior performance using only 0.5B tokens vs. full training with 3B tokens.
Conclusion: OPUS provides an efficient dynamic data selection framework that significantly improves pre-training efficiency and data utilization, especially valuable in specialized domains and as high-quality data becomes scarce.
Abstract: As high-quality public text approaches exhaustion, a phenomenon known as the Data Wall, pre-training is shifting from more tokens to better tokens. However, existing methods either rely on heuristic static filters that ignore training dynamics, or use dynamic yet optimizer-agnostic criteria based on raw gradients. We propose OPUS (Optimizer-induced Projected Utility Selection), a dynamic data selection framework that defines utility in the optimizer-induced update space. OPUS scores candidates by projecting their effective updates, shaped by modern optimizers, onto a target direction derived from a stable, in-distribution proxy. To ensure scalability, we employ Ghost technique with CountSketch for computational efficiency, and Boltzmann sampling for data diversity, incurring only 4.7% additional compute overhead. OPUS achieves remarkable results across diverse corpora, quality tiers, optimizers, and model scales. In pre-training of GPT-2 Large/XL on FineWeb and FineWeb-Edu with 30B tokens, OPUS outperforms industrial-level baselines and even full 200B-token training. Moreover, when combined with industrial-level static filters, OPUS further improves pre-training efficiency, even with lower-quality data. Furthermore, in continued pre-training of Qwen3-8B-Base on SciencePedia, OPUS achieves superior performance using only 0.5B tokens compared to full training with 3B tokens, demonstrating significant data efficiency gains in specialized domains.
[181] Reinforcement World Model Learning for LLM-based Agents
Xiao Yu, Baolin Peng, Ruize Xu, Yelong Shen, Pengcheng He, Suman Nath, Nikhil Singh, Jiangfeng Gao, Zhou Yu
Main category: cs.CL
TL;DR: RWML learns action-conditioned world models for LLM-based agents using sim-to-real gap rewards to align simulated next states with actual environment dynamics in text-based environments.
Details
Motivation: LLMs struggle in agentic settings to anticipate action consequences and adapt to environment dynamics, highlighting the need for world-modeling capabilities in LLM-based agents.Method: Reinforcement World Model Learning (RWML) - a self-supervised method that learns action-conditioned world models on textual states using sim-to-real gap rewards. It aligns simulated next states with realized next states in a pre-trained embedding space, providing more robust training than next-state token prediction.
Result: Significant gains over base model on ALFWorld and τ² Bench. When combined with task-success rewards, outperforms direct task-success reward RL by 6.9 and 5.7 points respectively, while matching expert-data training performance.
Conclusion: RWML provides an effective self-supervised approach for learning world models in LLM-based agents, improving their ability to anticipate action consequences and adapt to environment dynamics in text-based environments.
Abstract: Large language models (LLMs) have achieved strong performance in language-centric tasks. However, in agentic settings, LLMs often struggle to anticipate action consequences and adapt to environment dynamics, highlighting the need for world-modeling capabilities in LLM-based agents. We propose Reinforcement World Model Learning (RWML), a self-supervised method that learns action-conditioned world models for LLM-based agents on textual states using sim-to-real gap rewards. Our method aligns simulated next states produced by the model with realized next states observed from the environment, encouraging consistency between internal world simulations and actual environment dynamics in a pre-trained embedding space. Unlike next-state token prediction, which prioritizes token-level fidelity (i.e., reproducing exact wording) over semantic equivalence and can lead to model collapse, our method provides a more robust training signal and is empirically less susceptible to reward hacking than LLM-as-a-judge. We evaluate our method on ALFWorld and $τ^2$ Bench and observe significant gains over the base model, despite being entirely self-supervised. When combined with task-success rewards, our method outperforms direct task-success reward RL by 6.9 and 5.7 points on ALFWorld and $τ^2$ Bench respectively, while matching the performance of expert-data training.
[182] KV-CoRE: Benchmarking Data-Dependent Low-Rank Compressibility of KV-Caches in LLMs
Jian Chen, Zhuoran Wang, Jiayu Qin, Ming Li, Meng Wang, Changyou Chen, Yin Chen, Qizhen Weng, Yirui Liu
Main category: cs.CL
TL;DR: KV-CoRE is an SVD-based method for quantifying the low-rank compressibility of kv-caches in LLMs, revealing systematic patterns across models, datasets, and languages.
Details
Motivation: KV-caches in large language models consume significant GPU memory bandwidth during autoregressive decoding, especially with growing context lengths. Existing compression approaches often overlook the data-dependent nature of kv-caches and their variation across different model layers.Method: KV-CoRE (KV-cache Compressibility by Rank Evaluation) uses Singular Value Decomposition (SVD) to compute optimal low-rank approximations under the Frobenius norm. It’s gradient-free and incremental, enabling efficient dataset-level, layer-wise evaluation. The method employs Normalized Effective Rank as a compressibility metric.
Result: Analysis across multiple models and datasets spanning five English domains and sixteen languages reveals systematic patterns linking compressibility to model architecture, training data, and language coverage. Normalized Effective Rank strongly correlates with performance degradation under compression.
Conclusion: The study establishes a principled evaluation framework and the first large-scale benchmark for kv-cache compressibility in LLMs, offering insights for dynamic, data-aware compression strategies and data-centric model development.
Abstract: Large language models rely on kv-caches to avoid redundant computation during autoregressive decoding, but as context length grows, reading and writing the cache can quickly saturate GPU memory bandwidth. Recent work has explored KV-cache compression, yet most approaches neglect the data-dependent nature of kv-caches and their variation across layers. We introduce KV-CoRE KV-cache Compressibility by Rank Evaluation), an SVD-based method for quantifying the data-dependent low-rank compressibility of kv-caches. KV-CoRE computes the optimal low-rank approximation under the Frobenius norm and, being gradient-free and incremental, enables efficient dataset-level, layer-wise evaluation. Using this method, we analyze multiple models and datasets spanning five English domains and sixteen languages, uncovering systematic patterns that link compressibility to model architecture, training data, and language coverage. As part of this analysis, we employ the Normalized Effective Rank as a metric of compressibility and show that it correlates strongly with performance degradation under compression. Our study establishes a principled evaluation framework and the first large-scale benchmark of kv-cache compressibility in LLMs, offering insights for dynamic, data-aware compression and data-centric model development.
[183] Rethinking Memory Mechanisms of Foundation Agents in the Second Half: A Survey
Wei-Chieh Huang, Weizhi Zhang, Yueqing Liang, Yuanchen Bei, Yankai Chen, Tao Feng, Xinyu Pan, Zhen Tan, Yu Wang, Tianxin Wei, Shanglin Wu, Ruiyao Xu, Liangwei Yang, Rui Yang, Wooseong Yang, Chin-Yuan Yeh, Hanrong Zhang, Haozhen Zhang, Siqi Zhu, Henry Peng Zou, Wanjia Zhao, Song Wang, Wujiang Xu, Zixuan Ke, Zheng Hui, Dawei Li, Yaozu Wu, Langzhou He, Chen Wang, Xiongxiao Xu, Baixiang Huang, Juntao Tan, Shelby Heinecke, Huan Wang, Caiming Xiong, Ahmed A. Metwally, Jun Yan, Chen-Yu Lee, Hanqing Zeng, Yinglong Xia, Xiaokai Wei, Ali Payani, Yu Wang, Haitong Ma, Wenya Wang, Chengguang Wang, Yu Zhang, Xin Wang, Yongfeng Zhang, Jiaxuan You, Hanghang Tong, Xiao Luo, Xue Liu, Yizhou Sun, Wei Wang, Julian McAuley, James Zou, Jiawei Han, Philip S. Yu, Kai Shu
Main category: cs.CL
TL;DR: Survey paper on foundation agent memory systems, analyzing memory dimensions, topologies, learning policies, and evaluation benchmarks for AI agents in long-horizon, dynamic environments.
Details
Motivation: AI research is shifting from benchmark chasing to real-world utility, requiring agents to handle long-horizon, dynamic, user-dependent environments with context explosion. Memory emerges as the critical solution to bridge the utility gap.Method: Provides a unified framework for foundation agent memory across three dimensions: memory substrate (internal/external), cognitive mechanism (episodic, semantic, sensory, working, procedural), and memory subject (agent/user-centric). Analyzes memory instantiation under different agent topologies and learning policies for memory operations.
Result: Comprehensive survey organizing the rapidly growing field of agent memory (hundreds of papers this year), establishing a taxonomy for memory systems, and identifying key evaluation benchmarks and metrics for assessing memory utility.
Conclusion: Memory is essential for AI agents to achieve real-world utility in complex environments. The survey provides a structured framework for understanding memory systems, highlights current evaluation approaches, and outlines open challenges and future research directions.
Abstract: The research of artificial intelligence is undergoing a paradigm shift from prioritizing model innovations over benchmark scores towards emphasizing problem definition and rigorous real-world evaluation. As the field enters the “second half,” the central challenge becomes real utility in long-horizon, dynamic, and user-dependent environments, where agents face context explosion and must continuously accumulate, manage, and selectively reuse large volumes of information across extended interactions. Memory, with hundreds of papers released this year, therefore emerges as the critical solution to fill the utility gap. In this survey, we provide a unified view of foundation agent memory along three dimensions: memory substrate (internal and external), cognitive mechanism (episodic, semantic, sensory, working, and procedural), and memory subject (agent- and user-centric). We then analyze how memory is instantiated and operated under different agent topologies and highlight learning policies over memory operations. Finally, we review evaluation benchmarks and metrics for assessing memory utility, and outline various open challenges and future directions.
[184] Diffusion-State Policy Optimization for Masked Diffusion Language Models
Daisuke Oba, Hiroki Furuta, Naoaki Okazaki
Main category: cs.CL
TL;DR: DiSPO improves masked diffusion language models by optimizing intermediate filling decisions through branching and credit assignment without additional diffusion rollouts.
Details
Motivation: Masked diffusion language models generate via iterative denoising, but learning only from final rewards yields poor credit assignment for intermediate decisions, limiting optimization efficiency.Method: DiSPO branches at intermediate masked states by resampling fillings from cached logits, scores completions, and updates only newly filled tokens without extra diffusion rollouts, using a policy-gradient estimator combined with terminal-feedback optimization.
Result: On LLaDA-8B-Instruct, DiSPO consistently outperforms terminal-feedback diffu-GRPO baseline on math and planning benchmarks under matched compute and optimizer steps.
Conclusion: DiSPO provides effective credit assignment for diffusion language models, improving performance on reasoning tasks without additional rollout overhead.
Abstract: Masked diffusion language models generate by iteratively filling masked tokens over multiple denoising steps, so learning only from a terminal reward on the final completion yields coarse credit assignment over intermediate decisions. We propose DiSPO (Diffusion-State Policy Optimization), a plug-in credit-assignment layer that directly optimizes intermediate filling decisions. At selected intermediate masked states, DiSPO branches by resampling fillings for the currently masked positions from rollout-cached logits, scores the resulting completions, and updates only the newly filled tokens – without additional multi-step diffusion rollouts. We formalize a fixed-state objective for branched completions and derive a policy-gradient estimator that can be combined with terminal-feedback policy optimization using the same rollouts. On LLaDA-8B-Instruct, DiSPO consistently improves over the terminal-feedback diffu-GRPO baseline on math and planning benchmarks under matched rollout compute and optimizer steps. Our code will be available at https://daioba.github.io/dispo .
[185] InftyThink+: Effective and Efficient Infinite-Horizon Reasoning via Reinforcement Learning
Yuchen Yan, Liang Jiang, Jin Jiang, Shuaicheng Li, Zujie Wen, Zhiqiang Zhang, Jun Zhou, Jian Shao, Yueting Zhuang, Yongliang Shen
Main category: cs.CL
TL;DR: InftyThink+ is an RL framework for optimizing iterative reasoning that learns when to summarize, what to preserve, and how to resume reasoning, improving accuracy and efficiency over conventional methods.
Details
Motivation: Current reasoning models suffer from quadratic cost, context length limits, and degraded reasoning due to lost-in-the-middle effects in chain-of-thought approaches. Existing iterative reasoning methods rely on fixed heuristics and fail to optimize summarization decisions.Method: InftyThink+ uses end-to-end reinforcement learning with model-controlled iteration boundaries and explicit summarization. It employs a two-stage training scheme: supervised cold-start followed by trajectory-level RL to learn strategic summarization and continuation decisions.
Result: InftyThink+ improves accuracy by 21% on AIME24, outperforms conventional long chain-of-thought RL, generalizes better to out-of-distribution benchmarks, reduces inference latency, and accelerates RL training.
Conclusion: The framework demonstrates improved reasoning efficiency alongside stronger performance by optimizing the entire iterative reasoning trajectory through learned summarization strategies.
Abstract: Large reasoning models achieve strong performance by scaling inference-time chain-of-thought, but this paradigm suffers from quadratic cost, context length limits, and degraded reasoning due to lost-in-the-middle effects. Iterative reasoning mitigates these issues by periodically summarizing intermediate thoughts, yet existing methods rely on supervised learning or fixed heuristics and fail to optimize when to summarize, what to preserve, and how to resume reasoning. We propose InftyThink+, an end-to-end reinforcement learning framework that optimizes the entire iterative reasoning trajectory, building on model-controlled iteration boundaries and explicit summarization. InftyThink+ adopts a two-stage training scheme with supervised cold-start followed by trajectory-level reinforcement learning, enabling the model to learn strategic summarization and continuation decisions. Experiments on DeepSeek-R1-Distill-Qwen-1.5B show that InftyThink+ improves accuracy by 21% on AIME24 and outperforms conventional long chain-of-thought reinforcement learning by a clear margin, while also generalizing better to out-of-distribution benchmarks. Moreover, InftyThink+ significantly reduces inference latency and accelerates reinforcement learning training, demonstrating improved reasoning efficiency alongside stronger performance.
cs.CV
[186] Scalable spatial point process models for forensic footwear analysis
Alokesh Manna, Neil Spencer, Dipak K. Dey
Main category: cs.CV
TL;DR: A hierarchical Bayesian model for quantifying the rarity of accidental patterns in forensic shoe prints to improve evidence strength assessment
Details
Motivation: Forensic shoe print analysis needs better methods to quantify the rarity of accidental patterns (cuts, scrapes) that accumulate on shoe soles, as current approaches don't sufficiently distinguish between common and highly distinctive patterns that could uniquely identify a suspect's shoe.Method: Developed a hierarchical Bayesian model using latent Gaussian modeling for efficient inference on large datasets via integrated nested Laplace approximations, incorporating spatially varying coefficients to model relationships between shoe tread patterns and accidental locations.
Result: Demonstrated superior performance on held-out data compared to existing methods, enhancing accuracy and reliability in forensic shoe print analysis.
Conclusion: The proposed hierarchical Bayesian model provides a more accurate and scalable approach for quantifying accidental pattern rarity in shoe prints, improving forensic evidence assessment in criminal investigations.
Abstract: Shoe print evidence recovered from crime scenes plays a key role in forensic investigations. By examining shoe prints, investigators can determine details of the footwear worn by suspects. However, establishing that a suspect’s shoes match the make and model of a crime scene print may not be sufficient. Typically, thousands of shoes of the same size, make, and model are manufactured, any of which could be responsible for the print. Accordingly, a popular approach used by investigators is to examine the print for signs of ``accidentals,’’ i.e., cuts, scrapes, and other features that accumulate on shoe soles after purchase due to wear. While some patterns of accidentals are common on certain types of shoes, others are highly distinctive, potentially distinguishing the suspect’s shoe from all others. Quantifying the rarity of a pattern is thus essential to accurately measuring the strength of forensic evidence. In this study, we address this task by developing a hierarchical Bayesian model. Our improvement over existing methods primarily stems from two advancements. First, we frame our approach in terms of a latent Gaussian model, thus enabling inference to be efficiently scaled to large collections of annotated shoe prints via integrated nested Laplace approximations. Second, we incorporate spatially varying coefficients to model the relationship between shoes’ tread patterns and accidental locations. We demonstrate these improvements through superior performance on held-out data, which enhances accuracy and reliability in forensic shoe print analysis.
[187] Modality Gap-Driven Subspace Alignment Training Paradigm For Multimodal Large Language Models
Xiaomin Yu, Yi Xin, Wenjie Zhang, Chonghan Liu, Hanzhen Zhao, Xiaoxing Hu, Xinlei Yu, Ziyue Qiao, Hao Tang, Xue Yang, Xiaobin Hu, Chengwei Qin, Hui Xiong, Yu Qiao, Shuicheng Yan
Main category: cs.CV
TL;DR: ReAlign and ReVision framework addresses modality gap in multimodal learning using statistical alignment of unpaired data to enable efficient scaling of MLLMs
Details
Motivation: The modality gap - systematic offset between embeddings of different modalities expressing identical semantics - persists despite multimodal contrastive learning success. Prior approaches are limited by oversimplified isotropic assumptions, hindering large-scale application.Method: 1) Fixed-frame Modality Gap Theory decomposes gap into stable biases and anisotropic residuals. 2) ReAlign: training-free alignment strategy using massive unpaired data statistics with Anchor, Trace, and Centroid Alignment steps. 3) ReVision: scalable MLLM training paradigm integrating ReAlign into pretraining to learn visual representation distribution from unpaired text before visual instruction tuning.
Result: Framework demonstrates statistically aligned unpaired data can effectively substitute for expensive image-text pairs, offering robust path for efficient scaling of Multimodal Large Language Models.
Conclusion: Precise geometric characterization of modality gap enables efficient model scaling through statistical alignment of unpaired data, reducing reliance on large-scale, high-quality image-text pairs for MLLM development.
Abstract: Despite the success of multimodal contrastive learning in aligning visual and linguistic representations, a persistent geometric anomaly, the Modality Gap, remains: embeddings of distinct modalities expressing identical semantics occupy systematically offset regions. Prior approaches to bridge this gap are largely limited by oversimplified isotropic assumptions, hindering their application in large-scale scenarios. In this paper, we address these limitations by precisely characterizing the geometric shape of the modality gap and leveraging it for efficient model scaling. First, we propose the Fixed-frame Modality Gap Theory, which decomposes the modality gap within a frozen reference frame into stable biases and anisotropic residuals. Guided by this precise modeling, we introduce ReAlign, a training-free modality alignment strategy. Utilizing statistics from massive unpaired data, ReAlign aligns text representation into the image representation distribution via a three-step process comprising Anchor, Trace, and Centroid Alignment, thereby explicitly rectifying geometric misalignment. Building on ReAlign, we propose ReVision, a scalable training paradigm for Multimodal Large Language Models (MLLMs). ReVision integrates ReAlign into the pretraining stage, enabling the model to learn the distribution of visual representations from unpaired text before visual instruction tuning, without the need for large-scale, high-quality image-text pairs. Our framework demonstrates that statistically aligned unpaired data can effectively substitute for expensive image-text pairs, offering a robust path for the efficient scaling of MLLMs.
[188] Where Not to Learn: Prior-Aligned Training with Subset-based Attribution Constraints for Reliable Decision-Making
Ruoyu Chen, Shangquan Sun, Xiaoqing Guo, Sanyi Zhang, Kangwei Liu, Shiming Liu, Zhangcheng Wang, Qunli Zhang, Hua Zhang, Xiaochun Cao
Main category: cs.CV
TL;DR: A method for aligning model decision evidence with human priors using attribution-based constraints during training to improve reliability and reduce shortcut learning.
Details
Motivation: Models often achieve high accuracy through shortcut correlations rather than intended evidence, and aligning learned representations with human perception remains challenging despite human priors being available.Method: Proposes attribution-based human prior alignment that encodes human priors as expected input regions (e.g., bounding boxes), uses subset-selection-based attribution to expose model decision evidence, and penalizes deviations from prior regions through a training objective with attribution constraints.
Result: Validated on image classification and click decision tasks in MLLM-based GUI agent models, showing consistent improvements in task accuracy and enhanced decision reasonability across conventional classification and autoregressive generation settings.
Conclusion: Human prior alignment through attribution constraints effectively improves model reliability by encouraging models to base decisions on intended evidence rather than shortcut correlations.
Abstract: Reliable models should not only predict correctly, but also justify decisions with acceptable evidence. Yet conventional supervised learning typically provides only class-level labels, allowing models to achieve high accuracy through shortcut correlations rather than the intended evidence. Human priors can help constrain such behavior, but aligning models to these priors remains challenging because learned representations often diverge from human perception. To address this challenge, we propose an attribution-based human prior alignment method. We encode human priors as input regions that the model is expected to rely on (e.g., bounding boxes), and leverage a highly faithful subset-selection-based attribution approach to expose the model’s decision evidence during training. When the attribution region deviates substantially from the prior regions, we penalize reliance on off-prior evidence, encouraging the model to shift its attribution toward the intended regions. This is achieved through a training objective that imposes attribution constraints induced by the human prior. We validate our method on both image classification and click decision tasks in MLLM-based GUI agent models. Across conventional classification and autoregressive generation settings, human prior alignment consistently improves task accuracy while also enhancing the model’s decision reasonability.
[189] MAU-GPT: Enhancing Multi-type Industrial Anomaly Understanding via Anomaly-aware and Generalist Experts Adaptation
Zhuonan Wang, Zhenxuan Fan, Siwen Tan, Yu Zhong, Yuqian Yuan, Haoyuan Li, Hao Jiang, Wenqiao Zhang, Feifei Shao, Hongwei Wang, Jun Xiao
Main category: cs.CV
TL;DR: MAU-Set dataset and MAU-GPT model for industrial anomaly understanding with multimodal capabilities and hierarchical reasoning tasks
Details
Motivation: Need for automated fine-grained product image analysis in industrial manufacturing, addressing limitations of existing approaches with poor generalization across diverse anomaly patternsMethod: Introduces MAU-Set dataset spanning multiple industrial domains with hierarchical tasks, and MAU-GPT multimodal large model with novel AMoE-LoRA mechanism unifying anomaly-aware and generalist experts adaptation
Result: MAU-GPT consistently outperforms prior state-of-the-art methods across all domains, demonstrating strong potential for scalable automated industrial inspection
Conclusion: The proposed dataset and model provide comprehensive solution for industrial anomaly understanding with enhanced multimodal reasoning capabilities
Abstract: As industrial manufacturing scales, automating fine-grained product image analysis has become critical for quality control. However, existing approaches are hindered by limited dataset coverage and poor model generalization across diverse and complex anomaly patterns. To address these challenges, we introduce MAU-Set, a comprehensive dataset for Multi-type industrial Anomaly Understanding. It spans multiple industrial domains and features a hierarchical task structure, ranging from binary classification to complex reasoning. Alongside this dataset, we establish a rigorous evaluation protocol to facilitate fair and comprehensive model assessment. Building upon this foundation, we further present MAU-GPT, a domain-adapted multimodal large model specifically designed for industrial anomaly understanding. It incorporates a novel AMoE-LoRA mechanism that unifies anomaly-aware and generalist experts adaptation, enhancing both understanding and reasoning across diverse defect classes. Extensive experiments show that MAU-GPT consistently outperforms prior state-of-the-art methods across all domains, demonstrating strong potential for scalable and automated industrial inspection.
[190] A General Model for Retinal Segmentation and Quantification
Zhonghua Wang, Lie Ju, Sijia Li, Wei Feng, Sijin Zhou, Ming Hu, Jianhao Xiong, Xiaoying Tang, Yifan Peng, Mingquan Lin, Yaodong Ding, Yong Zeng, Wenbin Wei, Li Dong, Zongyuan Ge
Main category: cs.CV
TL;DR: RetSAM is a comprehensive retinal segmentation and quantification framework for fundus imaging that enables multi-target segmentation and standardized biomarker extraction for large-scale ophthalmic research.
Details
Motivation: Retinal imaging offers valuable structural and vascular signals for health assessment, but large-scale analysis is limited by lack of public multi-label datasets and unified segmentation-to-quantification pipelines.Method: Multi-stage training on over 200,000 fundus images supporting three task categories: anatomical structures, retinal phenotypic patterns, and lesion types, with conversion to over 30 standardized biomarkers.
Result: Achieves superior segmentation performance on 17 public datasets, improving prior methods by 3.9 percentage points in DSC on average, with up to 15 percentage points on challenging multi-task benchmarks.
Conclusion: RetSAM transforms fundus images into standardized quantitative phenotypes, enabling systematic correlation analyses across major ophthalmic diseases and large-scale ophthalmic research.
Abstract: Retinal imaging is fast, non-invasive, and widely available, offering quantifiable structural and vascular signals for ophthalmic and systemic health assessment. This accessibility creates an opportunity to study how quantitative retinal phenotypes relate to ocular and systemic diseases. However, such analyses remain difficult at scale due to the limited availability of public multi-label datasets and the lack of a unified segmentation-to-quantification pipeline. We present RetSAM, a general retinal segmentation and quantification framework for fundus imaging. It delivers robust multi-target segmentation and standardized biomarker extraction, supporting downstream ophthalmologic studies and oculomics correlation analyses. Trained on over 200,000 fundus images, RetSAM supports three task categories and segments five anatomical structures, four retinal phenotypic patterns, and more than 20 distinct lesion types. It converts these segmentation results into over 30 standardized biomarkers that capture structural morphology, vascular geometry, and degenerative changes. Trained with a multi-stage strategy using both private and public fundus data, RetSAM achieves superior segmentation performance on 17 public datasets. It improves on prior best methods by 3.9 percentage points in DSC on average, with up to 15 percentage points on challenging multi-task benchmarks, and generalizes well across diverse populations, imaging devices, and clinical settings. The resulting biomarkers enable systematic correlation analyses across major ophthalmic diseases, including diabetic retinopathy, age-related macular degeneration, glaucoma, and pathologic myopia. Together, RetSAM transforms fundus images into standardized, interpretable quantitative phenotypes, enabling large-scale ophthalmic research and translation.
[191] Steering to Say No: Configurable Refusal via Activation Steering in Vision Language Models
Jiaxi Yang, Shicheng Liu, Yuchen Yang, Dongwon Lee
Main category: cs.CV
TL;DR: CR-VLM introduces a configurable refusal mechanism for Vision Language Models using activation steering with teacher-forced refusal vectors, gating mechanisms, and counterfactual vision enhancement to balance safety and utility.
Details
Motivation: Existing refusal strategies in VLMs are one-size-fits-all and fail to adapt to diverse user needs and contextual constraints, leading to either under-refusal (insufficient safety) or over-refusal (reduced utility).Method: Three integrated components: (1) extracting configurable refusal vectors via teacher-forced mechanism to amplify refusal signals; (2) gating mechanism to mitigate over-refusal by preserving acceptance for in-scope queries; (3) counterfactual vision enhancement module aligning visual representations with refusal requirements.
Result: Comprehensive experiments across multiple datasets and various VLMs demonstrate CR-VLM achieves effective, efficient, and robust configurable refusals, offering scalable user-adaptive safety alignment.
Conclusion: CR-VLM provides a robust and efficient approach for configurable refusal in VLMs, enabling better balance between safety and utility through adaptive refusal mechanisms.
Abstract: With the rapid advancement of Vision Language Models (VLMs), refusal mechanisms have become a critical component for ensuring responsible and safe model behavior. However, existing refusal strategies are largely \textit{one-size-fits-all} and fail to adapt to diverse user needs and contextual constraints, leading to either under-refusal or over-refusal. In this work, we firstly explore the challenges mentioned above and develop \textbf{C}onfigurable \textbf{R}efusal in \textbf{VLM}s (\textbf{CR-VLM}), a robust and efficient approach for {\em configurable} refusal based on activation steering. CR-VLM consists of three integrated components: (1) extracting a configurable refusal vector via a teacher-forced mechanism to amplify the refusal signal; (2) introducing a gating mechanism that mitigates over-refusal by preserving acceptance for in-scope queries; and (3) designing a counterfactual vision enhancement module that aligns visual representations with refusal requirements. Comprehensive experiments across multiple datasets and various VLMs demonstrate that CR-VLM achieves effective, efficient, and robust configurable refusals, offering a scalable path toward user-adaptive safety alignment in VLMs.
[192] Learning Brain Representation with Hierarchical Visual Embeddings
Jiawen Zheng, Haonan Jia, Ming Li, Yuhui Zheng, Yufeng Zeng, Yang Gao, Chen Liang
Main category: cs.CV
TL;DR: A brain-image alignment method using multiple pre-trained visual encoders with contrastive learning and Fusion Prior to decode visual representations from brain signals with better accuracy and reconstruction fidelity.
Details
Motivation: Current visual decoding approaches from brain signals focus too much on high-level semantic features while neglecting pixel-level details, limiting our understanding of the human visual system. There's a need for better brain-image alignment strategies that capture hierarchical and multi-scale visual representations.Method: 1) Uses multiple pre-trained visual encoders with distinct inductive biases to capture hierarchical and multi-scale visual representations; 2) Employs contrastive learning objective for effective alignment between brain signals and visual embeddings; 3) Introduces Fusion Prior that learns stable mapping on large-scale visual data and matches brain features to this pre-trained prior for better distributional consistency across modalities.
Result: Extensive quantitative and qualitative experiments demonstrate the method achieves favorable balance between retrieval accuracy and reconstruction fidelity.
Conclusion: The proposed brain-image alignment strategy with multiple visual encoders and Fusion Prior effectively decodes visual representations from brain signals, capturing both semantic and pixel-level details for better understanding of human visual system.
Abstract: Decoding visual representations from brain signals has attracted significant attention in both neuroscience and artificial intelligence. However, the degree to which brain signals truly encode visual information remains unclear. Current visual decoding approaches explore various brain-image alignment strategies, yet most emphasize high-level semantic features while neglecting pixel-level details, thereby limiting our understanding of the human visual system. In this paper, we propose a brain-image alignment strategy that leverages multiple pre-trained visual encoders with distinct inductive biases to capture hierarchical and multi-scale visual representations, while employing a contrastive learning objective to achieve effective alignment between brain signals and visual embeddings. Furthermore, we introduce a Fusion Prior, which learns a stable mapping on large-scale visual data and subsequently matches brain features to this pre-trained prior, thereby enhancing distributional consistency across modalities. Extensive quantitative and qualitative experiments demonstrate that our method achieves a favorable balance between retrieval accuracy and reconstruction fidelity.
[193] Vectra: A New Metric, Dataset, and Model for Visual Quality Assessment in E-Commerce In-Image Machine Translation
Qingyu Wu, Yuxuan Han, Haijun Li, Zhao Xu, Jianshan Zhao, Xu Jin, Longyue Wang, Weihua Luo
Main category: cs.CV
TL;DR: Vectra: A reference-free MLLM-driven visual quality assessment framework for e-commerce In-Image Machine Translation, featuring multidimensional metrics, large-scale dataset, and 4B-parameter model.
Details
Motivation: Current visual quality assessment methods for e-commerce IIMT lack explainability and fine-grained reward signals, especially when dealing with context-dense product imagery and multimodal defects.Method: Three-component framework: (1) Vectra Score - 14 interpretable quality dimensions with spatially-aware Defect Area Ratio quantification; (2) Vectra Dataset - 1.1M real-world images with benchmark, reasoning annotations, and expert preferences; (3) Vectra Model - 4B-parameter MLLM generating scores and diagnostic reasoning.
Result: Vectra achieves state-of-the-art correlation with human rankings and outperforms leading MLLMs (GPT-5, Gemini-3) in scoring performance.
Conclusion: Vectra provides the first comprehensive reference-free visual quality assessment framework for e-commerce IIMT, addressing limitations of existing methods through interpretable metrics and MLLM-driven evaluation.
Abstract: In-Image Machine Translation (IIMT) powers cross-border e-commerce product listings; existing research focuses on machine translation evaluation, while visual rendering quality is critical for user engagement. When facing context-dense product imagery and multimodal defects, current reference-based methods (e.g., SSIM, FID) lack explainability, while model-as-judge approaches lack domain-grounded, fine-grained reward signals. To bridge this gap, we introduce Vectra, to the best of our knowledge, the first reference-free, MLLM-driven visual quality assessment framework for e-commerce IIMT. Vectra comprises three components: (1) Vectra Score, a multidimensional quality metric system that decomposes visual quality into 14 interpretable dimensions, with spatially-aware Defect Area Ratio (DAR) quantification to reduce annotation ambiguity; (2) Vectra Dataset, constructed from 1.1M real-world product images via diversity-aware sampling, comprising a 2K benchmark for system evaluation, 30K reasoning-based annotations for instruction tuning, and 3.5K expert-labeled preferences for alignment and evaluation; and (3) Vectra Model, a 4B-parameter MLLM that generates both quantitative scores and diagnostic reasoning. Experiments demonstrate that Vectra achieves state-of-the-art correlation with human rankings, and our model outperforms leading MLLMs, including GPT-5 and Gemini-3, in scoring performance. The dataset and model will be released upon acceptance.
[194] Robust and Real-Time Bangladeshi Currency Recognition: A Dual-Stream MobileNet and EfficientNet Approach
Subreena, Mohammad Amzad Hossain, Mirza Raquib, Saydul Akbar Murad, Farida Siddiqi Prity, Muhammad Hanif, Nick Rahimi
Main category: cs.CV
TL;DR: A hybrid CNN architecture combining MobileNetV3-Large and EfficientNetB0 with MLP classifier for Bangladeshi banknote recognition, achieving high accuracy on controlled and real-world datasets with explainable AI integration.
Details
Motivation: To develop an accurate currency recognition system for visually impaired individuals to prevent fraud and exploitation, addressing the lack of comprehensive Bangladeshi banknote datasets and limitations of current recognition models.Method: Built new Bangladeshi banknote dataset with controlled/real-world scenarios, incorporated four additional datasets, proposed hybrid CNN architecture combining MobileNetV3-Large and EfficientNetB0 for feature extraction with MLP classifier, used five-fold cross-validation with seven evaluation metrics, integrated explainable AI methods (LIME and SHAP).
Result: Achieved 97.95% accuracy on controlled datasets, 92.84% on complex backgrounds, and 94.98% accuracy when combining all datasets, with thorough evaluation using multiple metrics and explainable AI for transparency.
Conclusion: The proposed hybrid CNN architecture provides an efficient, accurate, and interpretable solution for Bangladeshi banknote recognition suitable for resource-constrained devices, addressing assistive technology needs for visually impaired individuals.
Abstract: Accurate currency recognition is essential for assistive technologies, particularly for visually impaired individuals who rely on others to identify banknotes. This dependency puts them at risk of fraud and exploitation. To address these challenges, we first build a new Bangladeshi banknote dataset that includes both controlled and real-world scenarios, ensuring a more comprehensive and diverse representation. Next, to enhance the dataset’s robustness, we incorporate four additional datasets, including public benchmarks, to cover various complexities and improve the model’s generalization. To overcome the limitations of current recognition models, we propose a novel hybrid CNN architecture that combines MobileNetV3-Large and EfficientNetB0 for efficient feature extraction. This is followed by an effective multilayer perceptron (MLP) classifier to improve performance while keeping computational costs low, making the system suitable for resource-constrained devices. The experimental results show that the proposed model achieves 97.95% accuracy on controlled datasets, 92.84% on complex backgrounds, and 94.98% accuracy when combining all datasets. The model’s performance is thoroughly evaluated using five-fold cross-validation and seven metrics: accuracy, precision, recall, F1-score, Cohen’s Kappa, MCC, and AUC. Additionally, explainable AI methods like LIME and SHAP are incorporated to enhance transparency and interpretability.
[195] PAND: Prompt-Aware Neighborhood Distillation for Lightweight Fine-Grained Visual Classification
Qiuming Luo, Yuebing Li, Feng Li, Chang Kong
Main category: cs.CV
TL;DR: PAND is a two-stage knowledge distillation framework for fine-grained visual classification that uses prompt-aware semantic calibration and neighborhood-aware structural distillation to transfer knowledge from large vision-language models to lightweight networks.
Details
Motivation: Current knowledge distillation methods in fine-grained visual classification rely on fixed prompts and global alignment, which limits their effectiveness in transferring nuanced visual knowledge from large vision-language models to lightweight student networks.Method: Two-stage framework: 1) Prompt-Aware Semantic Calibration generates adaptive semantic anchors, 2) Neighborhood-aware structural distillation constrains the student’s local decision structure to better capture fine-grained visual patterns.
Result: PAND consistently outperforms state-of-the-art methods on four FGVC benchmarks. ResNet-18 student achieves 76.09% accuracy on CUB-200, surpassing VL2Lite baseline by 3.4%.
Conclusion: PAND effectively addresses limitations of fixed prompts and global alignment in VLMs knowledge distillation for fine-grained visual classification through semantic calibration and structural transfer.
Abstract: Distilling knowledge from large Vision-Language Models (VLMs) into lightweight networks is crucial yet challenging in Fine-Grained Visual Classification (FGVC), due to the reliance on fixed prompts and global alignment. To address this, we propose PAND (Prompt-Aware Neighborhood Distillation), a two-stage framework that decouples semantic calibration from structural transfer. First, we incorporate Prompt-Aware Semantic Calibration to generate adaptive semantic anchors. Second, we introduce a neighborhood-aware structural distillation strategy to constrain the student’s local decision structure. PAND consistently outperforms state-of-the-art methods on four FGVC benchmarks. Notably, our ResNet-18 student achieves 76.09% accuracy on CUB-200, surpassing the strong baseline VL2Lite by 3.4%. Code is available at https://github.com/LLLVTA/PAND.
[196] Gaussian-Constrained LeJEPA Representations for Unsupervised Scene Discovery and Pose Consistency
Mohsen Mostafa
Main category: cs.CV
TL;DR: LeJEPA-inspired Gaussian constraints on image embeddings improve 3D scene reconstruction from unstructured image collections by enhancing scene separation and pose estimation in visually ambiguous settings.
Details
Motivation: Addressing the challenge of unsupervised 3D scene reconstruction from unstructured image collections, particularly when images come from multiple unrelated scenes with visual ambiguity, as highlighted by the Image Matching Challenge 2025.Method: Three progressively refined pipelines culminating in a LeJEPA-inspired approach that enforces isotropic Gaussian constraints on learned image embeddings to improve clustering consistency and pose estimation robustness.
Result: Experimental results on IMC2025 show Gaussian-constrained embeddings improve scene separation and pose plausibility compared to heuristic-driven baselines, especially in visually ambiguous settings.
Conclusion: Theoretically motivated representation constraints offer a promising direction for bridging self-supervised learning principles and practical structure-from-motion pipelines.
Abstract: Unsupervised 3D scene reconstruction from unstructured image collections remains a fundamental challenge in computer vision, particularly when images originate from multiple unrelated scenes and contain significant visual ambiguity. The Image Matching Challenge 2025 (IMC2025) highlights these difficulties by requiring both scene discovery and camera pose estimation under real-world conditions, including outliers and mixed content. This paper investigates the application of Gaussian-constrained representations inspired by LeJEPA (Joint Embedding Predictive Architecture) to address these challenges. We present three progressively refined pipelines, culminating in a LeJEPA-inspired approach that enforces isotropic Gaussian constraints on learned image embeddings. Rather than introducing new theoretical guarantees, our work empirically evaluates how these constraints influence clustering consistency and pose estimation robustness in practice. Experimental results on IMC2025 demonstrate that Gaussian-constrained embeddings can improve scene separation and pose plausibility compared to heuristic-driven baselines, particularly in visually ambiguous settings. These findings suggest that theoretically motivated representation constraints offer a promising direction for bridging self-supervised learning principles and practical structure-from-motion pipelines.
[197] GOT-Edit: Geometry-Aware Generic Object Tracking via Online Model Editing
Shih-Fang Chen, Jun-Cheng Chen, I-Hong Jhuo, Yen-Yu Lin
Main category: cs.CV
TL;DR: GOT-Edit integrates 3D geometric reasoning into 2D object tracking by using online model editing with a Visual Geometry Grounded Transformer to combine geometric cues with semantic features for improved robustness to occlusion and clutter.
Details
Motivation: Current generic object tracking (GOT) methods rely primarily on 2D features and neglect 3D geometric cues, making them vulnerable to occlusion, distractors, and appearance variations. Human perception naturally combines 3D knowledge with semantic reasoning for effective tracking.Method: GOT-Edit uses online cross-modality model editing with null-space constrained updates to integrate geometry-aware cues from a pre-trained Visual Geometry Grounded Transformer into a generic object tracker. The approach infers geometric information from few 2D images while preserving semantic discrimination.
Result: Extensive experiments on multiple GOT benchmarks show GOT-Edit achieves superior robustness and accuracy, particularly under occlusion and clutter conditions, outperforming existing methods.
Conclusion: GOT-Edit establishes a new paradigm for combining 2D semantics with 3D geometric reasoning in object tracking, demonstrating that integrating geometric cues significantly improves tracking robustness across diverse scenarios.
Abstract: Human perception for effective object tracking in a 2D video stream arises from the implicit use of prior 3D knowledge combined with semantic reasoning. In contrast, most generic object tracking (GOT) methods primarily rely on 2D features of the target and its surroundings while neglecting 3D geometric cues, which makes them susceptible to partial occlusion, distractors, and variations in geometry and appearance. To address this limitation, we introduce GOT-Edit, an online cross-modality model editing approach that integrates geometry-aware cues into a generic object tracker from a 2D video stream. Our approach leverages features from a pre-trained Visual Geometry Grounded Transformer to enable geometric cue inference from only a few 2D images. To tackle the challenge of seamlessly combining geometry and semantics, GOT-Edit performs online model editing with null-space constrained updates that incorporate geometric information while preserving semantic discrimination, yielding consistently better performance across diverse scenarios. Extensive experiments on multiple GOT benchmarks demonstrate that GOT-Edit achieves superior robustness and accuracy, particularly under occlusion and clutter, establishing a new paradigm for combining 2D semantics with 3D geometric reasoning for generic object tracking.
[198] XAI-CLIP: ROI-Guided Perturbation Framework for Explainable Medical Image Segmentation in Multimodal Vision-Language Models
Thuraya Alzubaidi, Sana Ammar, Maryam Alsharqi, Islem Rekik, Muzammil Behzad
Main category: cs.CV
TL;DR: XAI-CLIP: A multimodal vision-language framework for generating interpretable, efficient explanations for medical image segmentation using ROI-guided perturbations.
Details
Motivation: Transformer-based medical image segmentation models lack interpretability, hindering clinical trust. Existing XAI methods are computationally expensive, produce noisy explanations, and lack anatomical relevance.Method: Proposes XAI-CLIP framework that uses multimodal vision-language model embeddings to localize clinically meaningful anatomical regions, then applies targeted region-aware perturbations to generate boundary-aware saliency maps with reduced computational overhead.
Result: Achieves 60% runtime reduction, 44.6% dice score improvement, and 96.7% IoU increase for occlusion-based explanations on FLARE22 and CHAOS datasets compared to conventional methods.
Conclusion: Multimodal vision-language representations significantly enhance interpretability and efficiency of perturbation-based XAI, enabling transparent and clinically deployable medical image segmentation systems.
Abstract: Medical image segmentation is a critical component of clinical workflows, enabling accurate diagnosis, treatment planning, and disease monitoring. However, despite the superior performance of transformer-based models over convolutional architectures, their limited interpretability remains a major obstacle to clinical trust and deployment. Existing explainable artificial intelligence (XAI) techniques, including gradient-based saliency methods and perturbation-based approaches, are often computationally expensive, require numerous forward passes, and frequently produce noisy or anatomically irrelevant explanations. To address these limitations, we propose XAI-CLIP, an ROI-guided perturbation framework that leverages multimodal vision-language model embeddings to localize clinically meaningful anatomical regions and guide the explanation process. By integrating language-informed region localization with medical image segmentation and applying targeted, region-aware perturbations, the proposed method generates clearer, boundary-aware saliency maps while substantially reducing computational overhead. Experiments conducted on the FLARE22 and CHAOS datasets demonstrate that XAI-CLIP achieves up to a 60% reduction in runtime, a 44.6% improvement in dice score, and a 96.7% increase in Intersection-over-Union for occlusion-based explanations compared to conventional perturbation methods. Qualitative results further confirm cleaner and more anatomically consistent attribution maps with fewer artifacts, highlighting that the incorporation of multimodal vision-language representations into perturbation-based XAI frameworks significantly enhances both interpretability and efficiency, thereby enabling transparent and clinically deployable medical image segmentation systems.
[199] Deep Learning Based Multi-Level Classification for Aviation Safety
Elaheh Sabziyan Varnousfaderani, Syed A. M. Shihab, Jonathan King
Main category: cs.CV
TL;DR: CNN-based bird species classification framework for aviation safety that identifies bird species, flock formation type, and flock size from camera images to improve bird strike prevention.
Details
Motivation: Bird strikes threaten aviation safety but existing radar systems can't identify bird species, which is crucial since different species have distinct flight behaviors and altitudinal preferences. Species identification enables more accurate flight path prediction for prevention.Method: Proposes an image-based bird classification framework using Convolutional Neural Networks (CNNs) designed to work with camera systems. The CNN identifies bird species and includes dedicated classifiers for flock formation type and flock size estimation.
Result: The framework provides species identification plus supplementary information about flock characteristics (formation type and size) which offer insights into collective flight behavior, trajectory dispersion, and potential impact severity.
Conclusion: The CNN-based visual detection system addresses limitations of current radar systems by enabling species-specific bird strike prediction, with flock characteristics providing valuable additional safety information for aviation.
Abstract: Bird strikes pose a significant threat to aviation safety, often resulting in loss of life, severe aircraft damage, and substantial financial costs. Existing bird strike prevention strategies primarily rely on avian radar systems that detect and track birds in real time. A major limitation of these systems is their inability to identify bird species, an essential factor, as different species exhibit distinct flight behaviors, and altitudinal preference. To address this challenge, we propose an image-based bird classification framework using Convolutional Neural Networks (CNNs), designed to work with camera systems for autonomous visual detection. The CNN is designed to identify bird species and provide critical input to species-specific predictive models for accurate flight path prediction. In addition to species identification, we implemented dedicated CNN classifiers to estimate flock formation type and flock size. These characteristics provide valuable supplementary information for aviation safety. Specifically, flock type and size offer insights into collective flight behavior, and trajectory dispersion . Flock size directly relates to the potential impact severity, as the overall damage risk increases with the combined kinetic energy of multiple birds.
[200] Hierarchical Refinement of Universal Multimodal Attacks on Vision-Language Models
Peng-Fei Zhang, Zi Huang
Main category: cs.CV
TL;DR: HRA: Hierarchical Refinement Attack - a universal adversarial attack framework for Vision-Language Pretraining models that uses hierarchical optimization for images and importance modeling for text to create transferable perturbations.
Details
Motivation: Existing adversarial attacks for VLP models are sample-specific, causing high computational costs when scaling to large datasets or new scenarios. There's a need for universal attacks that can efficiently generate transferable perturbations across different samples.Method: Proposes Hierarchical Refinement Attack (HRA) with two components: 1) For images: uses temporal hierarchy of historical and estimated future gradients to refine optimization path and avoid local minima; 2) For text: hierarchically models textual importance considering both intra- and inter-sentence contributions to identify globally influential words for universal text perturbations.
Result: Extensive experiments across various downstream tasks, VLP models, and datasets demonstrate superior transferability of the proposed universal multimodal attacks compared to existing methods.
Conclusion: HRA provides an effective universal attack framework for VLP models that overcomes the computational limitations of sample-specific attacks while maintaining strong transferability across different scenarios.
Abstract: Existing adversarial attacks for VLP models are mostly sample-specific, resulting in substantial computational overhead when scaled to large datasets or new scenarios. To overcome this limitation, we propose Hierarchical Refinement Attack (HRA), a multimodal universal attack framework for VLP models. For the image modality, we refine the optimization path by leveraging a temporal hierarchy of historical and estimated future gradients to avoid local minima and stabilize universal perturbation learning. For the text modality, it hierarchically models textual importance by considering both intra- and inter-sentence contributions to identify globally influential words, which are then used as universal text perturbations. Extensive experiments across various downstream tasks, VLP models, and datasets, demonstrate the superior transferability of the proposed universal multimodal attacks.
[201] The Geometry of Representational Failures in Vision Language Models
Daniele Savietto, Declan Campbell, André Panisson, Marco Nurisso, Giovanni Petri, Jonathan D. Cohen, Alan Perotti
Main category: cs.CV
TL;DR: Vision-Language Models (VLMs) fail at multi-object tasks due to representational geometry issues, similar to human cognitive constraints like the Binding Problem. The paper analyzes concept vectors in VLMs to understand these failures.
Details
Motivation: VLMs exhibit puzzling failures in multi-object visual tasks, such as hallucinating non-existent elements or failing to identify similar objects among distractions. These errors mirror human cognitive constraints like the "Binding Problem," but the internal mechanisms in artificial systems remain poorly understood.Method: The paper proposes a mechanistic analysis by examining the representational geometry of open-weight VLMs (Qwen, InternVL, Gemma). It compares methodologies to distill “concept vectors” - latent directions encoding visual concepts. These concept vectors are validated via steering interventions that manipulate model behavior in both simplified and naturalistic vision tasks.
Result: The geometric overlap between concept vectors strongly correlates with specific error patterns. This provides a grounded quantitative framework to understand how internal representations shape model behavior and drive visual failures in VLMs.
Conclusion: The analysis of concept vectors and representational geometry offers mechanistic insights into VLM failures in multi-object tasks, providing a quantitative framework to understand how internal representations influence model behavior and visual errors.
Abstract: Vision-Language Models (VLMs) exhibit puzzling failures in multi-object visual tasks, such as hallucinating non-existent elements or failing to identify the most similar objects among distractions. While these errors mirror human cognitive constraints, such as the “Binding Problem”, the internal mechanisms driving them in artificial systems remain poorly understood. Here, we propose a mechanistic insight by analyzing the representational geometry of open-weight VLMs (Qwen, InternVL, Gemma), comparing methodologies to distill “concept vectors” - latent directions encoding visual concepts. We validate our concept vectors via steering interventions that reliably manipulate model behavior in both simplified and naturalistic vision tasks (e.g., forcing the model to perceive a red flower as blue). We observe that the geometric overlap between these vectors strongly correlates with specific error patterns, offering a grounded quantitative framework to understand how internal representations shape model behavior and drive visual failures.
[202] Fair Context Learning for Evidence-Balanced Test-Time Adaptation in Vision-Language Models
Sanggeon Yun, Ryozo Masukawa, SungHeon Jeong, Wenjun Huang, Hanning Chen, Mohsen Imani
Main category: cs.CV
TL;DR: FCL is a test-time adaptation method for vision-language models that addresses shared-evidence bias through fairness-driven calibration instead of entropy minimization, improving robustness to distribution shifts.
Details
Motivation: Vision-language models like CLIP degrade under distribution shifts, and existing test-time adaptation methods rely on entropy minimization which can amplify spurious correlations and cause overconfident errors when classes share visual features.Method: Fair Context Learning (FCL) uses episodic TTA with two components: (1) augmentation-based exploration to identify plausible class candidates, and (2) fairness-driven calibration that adapts text contexts to equalize sensitivity to common visual evidence, avoiding entropy minimization.
Result: FCL achieves competitive adaptation performance relative to state-of-the-art TTA methods across diverse domain-shift and fine-grained benchmarks, validating the theoretical motivation.
Conclusion: FCL provides an effective alternative to entropy minimization for test-time adaptation of VLMs, addressing shared-evidence bias through fairness constraints to improve robustness to distribution shifts.
Abstract: Vision-Language Models (VLMs) such as CLIP enable strong zero-shot recognition but suffer substantial degradation under distribution shifts. Test-Time Adaptation (TTA) aims to improve robustness using only unlabeled test samples, yet most prompt-based TTA methods rely on entropy minimization – an approach that can amplify spurious correlations and induce overconfident errors when classes share visual features. We propose Fair Context Learning (FCL), an episodic TTA framework that avoids entropy minimization by explicitly addressing shared-evidence bias. Motivated by our additive evidence decomposition assumption, FCL decouples adaptation into (i) augmentation-based exploration to identify plausible class candidates, and (ii) fairness-driven calibration that adapts text contexts to equalize sensitivity to common visual evidence. This fairness constraint mitigates partial feature obsession and enables effective calibration of text embeddings without relying on entropy reduction. Through extensive evaluation, we empirically validate our theoretical motivation and show that FCL achieves competitive adaptation performance relative to state-of-the-art TTA methods across diverse domain-shift and fine-grained benchmarks.
[203] MOVA: Towards Scalable and Synchronized Video-Audio Generation
SII-OpenMOSS Team, :, Donghua Yu, Mingshu Chen, Qi Chen, Qi Luo, Qianyi Wu, Qinyuan Cheng, Ruixiao Li, Tianyi Liang, Wenbo Zhang, Wenming Tu, Xiangyu Peng, Yang Gao, Yanru Huo, Ying Zhu, Yinze Luo, Yiyang Zhang, Yuerong Song, Zhe Xu, Zhiyu Zhang, Chenchen Yang, Cheng Chang, Chushu Zhou, Hanfu Chen, Hongnan Ma, Jiaxi Li, Jingqi Tong, Junxi Liu, Ke Chen, Shimin Li, Songlin Wang, Wei Jiang, Zhaoye Fei, Zhiyuan Ning, Chunguo Li, Chenhui Li, Ziwei He, Zengfeng Huang, Xie Chen, Xipeng Qiu
Main category: cs.CV
TL;DR: MOVA is an open-source 32B parameter Mixture-of-Experts model that jointly generates synchronized high-quality video and audio content from image-text inputs, addressing limitations of cascaded pipelines in audio-visual generation.
Details
Motivation: Current audio-visual generation relies on cascaded pipelines that increase costs, accumulate errors, and degrade quality. Existing joint generation systems like Veo 3 and Sora 2 are closed-source, limiting research progress. There's a need for open-source models that can generate synchronized audio-visual content including lip-synced speech, sound effects, and music.Method: MOVA uses a Mixture-of-Experts architecture with 32B total parameters (18B active during inference). It supports Image-Text to Video-Audio (IT2VA) generation tasks. The model is designed for joint multimodal modeling of audio and video streams.
Result: MOVA generates high-quality, synchronized audio-visual content including realistic lip-synced speech, environment-aware sound effects, and content-aligned music. The model weights and code are released to advance research.
Conclusion: MOVA provides an open-source solution for joint audio-visual generation, addressing challenges in architecture, data, and training. The release aims to foster community development and research in multimodal generation.
Abstract: Audio is indispensable for real-world video, yet generation models have largely overlooked audio components. Current approaches to producing audio-visual content often rely on cascaded pipelines, which increase cost, accumulate errors, and degrade overall quality. While systems such as Veo 3 and Sora 2 emphasize the value of simultaneous generation, joint multimodal modeling introduces unique challenges in architecture, data, and training. Moreover, the closed-source nature of existing systems limits progress in the field. In this work, we introduce MOVA (MOSS Video and Audio), an open-source model capable of generating high-quality, synchronized audio-visual content, including realistic lip-synced speech, environment-aware sound effects, and content-aligned music. MOVA employs a Mixture-of-Experts (MoE) architecture, with a total of 32B parameters, of which 18B are active during inference. It supports IT2VA (Image-Text to Video-Audio) generation task. By releasing the model weights and code, we aim to advance research and foster a vibrant community of creators. The released codebase features comprehensive support for efficient inference, LoRA fine-tuning, and prompt enhancement.
[204] A Comparative Study of Adversarial Robustness in CNN and CNN-ANFIS Architectures
Kaaustaaub Shankar, Bharadwaj Dogga, Kelly Cohen
Main category: cs.CV
TL;DR: ANFIS-augmented CNNs show mixed results: ResNet18-ANFIS improves adversarial robustness against PGD and Square attacks, while VGG-ANFIS often underperforms baseline models, indicating architecture-dependent effects of neuro-fuzzy integration.
Details
Motivation: Standard CNNs lack interpretability and are vulnerable to adversarial attacks. While neuro-fuzzy hybrids like DCNFIS improve interpretability by replacing fully connected classifiers with ANFIS, their robustness against adversarial attacks remains underexplored.Method: Compared standard CNNs (ConvNet, VGG, ResNet18) with their ANFIS-augmented counterparts on MNIST, Fashion-MNIST, CIFAR-10, and CIFAR-100 datasets under gradient-based (PGD) and gradient-free (Square) adversarial attacks.
Result: ANFIS integration does not consistently improve clean accuracy. Robustness effects are architecture-dependent: ResNet18-ANFIS exhibits improved adversarial robustness, while VGG-ANFIS often underperforms its baseline counterpart.
Conclusion: Neuro-fuzzy augmentation can enhance adversarial robustness in specific CNN architectures but is not universally beneficial, highlighting the importance of architecture selection when implementing such hybrid approaches.
Abstract: Convolutional Neural Networks (CNNs) achieve strong image classification performance but lack interpretability and are vulnerable to adversarial attacks. Neuro-fuzzy hybrids such as DCNFIS replace fully connected CNN classifiers with Adaptive Neuro-Fuzzy Inference Systems (ANFIS) to improve interpretability, yet their robustness remains underexplored. This work compares standard CNNs (ConvNet, VGG, ResNet18) with their ANFIS-augmented counterparts on MNIST, Fashion-MNIST, CIFAR-10, and CIFAR-100 under gradient-based (PGD) and gradient-free (Square) attacks. Results show that ANFIS integration does not consistently improve clean accuracy and has architecture-dependent effects on robustness: ResNet18-ANFIS exhibits improved adversarial robustness, while VGG-ANFIS often underperforms its baseline. These findings suggest that neuro-fuzzy augmentation can enhance robustness in specific architectures but is not universally beneficial.
[205] UNIKIE-BENCH: Benchmarking Large Multimodal Models for Key Information Extraction in Visual Documents
Yifan Ji, Zhipeng Xu, Zhenghao Liu, Zulong Chen, Qian Zhang, Zhibo Yang, Junyang Lin, Yu Gu, Ge Yu, Maosong Sun
Main category: cs.CV
TL;DR: UNIKIE-BENCH is a unified benchmark for evaluating Large Multimodal Models’ Key Information Extraction capabilities from document images, featuring constrained and open-category tracks to assess performance across diverse real-world scenarios.
Details
Motivation: Key Information Extraction from real-world documents is challenging due to layout variations, visual quality issues, and task-specific requirements. While Large Multimodal Models show promise for end-to-end KIE, there's a need for comprehensive evaluation across diverse application scenarios to understand their capabilities and limitations.Method: The authors introduce UNIKIE-BENCH, a unified benchmark with two complementary tracks: 1) constrained-category KIE with scenario-predefined schemas reflecting practical needs, and 2) open-category KIE extracting any explicitly present key information. They evaluate 15 state-of-the-art LMMs on this benchmark.
Result: Experiments reveal substantial performance degradation under diverse schema definitions, long-tail key fields, and complex layouts. There are pronounced performance disparities across different document types and scenarios, highlighting challenges in grounding accuracy and layout-aware reasoning for LMM-based KIE.
Conclusion: The benchmark reveals persistent challenges in LMM-based KIE, particularly in grounding accuracy and layout-aware reasoning. UNIKIE-BENCH provides a comprehensive evaluation framework to advance research in document understanding and multimodal information extraction.
Abstract: Key Information Extraction (KIE) from real-world documents remains challenging due to substantial variations in layout structures, visual quality, and task-specific information requirements. Recent Large Multimodal Models (LMMs) have shown promising potential for performing end-to-end KIE directly from document images. To enable a comprehensive and systematic evaluation across realistic and diverse application scenarios, we introduce UNIKIE-BENCH, a unified benchmark designed to rigorously evaluate the KIE capabilities of LMMs. UNIKIE-BENCH consists of two complementary tracks: a constrained-category KIE track with scenario-predefined schemas that reflect practical application needs, and an open-category KIE track that extracts any key information that is explicitly present in the document. Experiments on 15 state-of-the-art LMMs reveal substantial performance degradation under diverse schema definitions, long-tail key fields, and complex layouts, along with pronounced performance disparities across different document types and scenarios. These findings underscore persistent challenges in grounding accuracy and layout-aware reasoning for LMM-based KIE. All codes and datasets are available at https://github.com/NEUIR/UNIKIE-BENCH.
[206] OMNI-Dent: Towards an Accessible and Explainable AI Framework for Automated Dental Diagnosis
Leeje Jang, Yao-Yi Chiang, Angela M. Hastings, Patimaporn Pungchanchaikul, Martha B. Lucas, Emily C. Schultz, Jeffrey P. Louie, Mohamed Estai, Wen-Chen Wang, Ryan H. L. Ip, Boyen Huang
Main category: cs.CV
TL;DR: OMNI-Dent is a vision-language model framework for dental diagnosis using smartphone photos, incorporating clinical reasoning without dental-specific fine-tuning.
Details
Motivation: Current AI dental diagnosis methods treat it as visual pattern recognition without clinical reasoning, require expert-annotated data, and struggle with real-world generalization. Need for accessible dental evaluation tools.Method: Uses a general-purpose VLM with embedded diagnostic heuristics from dental experts, operates on multi-view smartphone photographs, performs tooth-level evaluation without dental-specific fine-tuning.
Result: Framework enables dental diagnosis in settings without curated clinical imaging, serves as early-stage assistive tool to identify abnormalities and determine need for professional evaluation.
Conclusion: OMNI-Dent offers data-efficient, explainable dental diagnosis using VLMs with clinical reasoning, providing accessible option for limited healthcare access.
Abstract: Accurate dental diagnosis is essential for oral healthcare, yet many individuals lack access to timely professional evaluation. Existing AI-based methods primarily treat diagnosis as a visual pattern recognition task and do not reflect the structured clinical reasoning used by dental professionals. These approaches also require large amounts of expert-annotated data and often struggle to generalize across diverse real-world imaging conditions. To address these limitations, we present OMNI-Dent, a data-efficient and explainable diagnostic framework that incorporates clinical reasoning principles into a Vision-Language Model (VLM)-based pipeline. The framework operates on multi-view smartphone photographs,embeds diagnostic heuristics from dental experts, and guides a general-purpose VLM to perform tooth-level evaluation without dental-specific fine-tuning of the VLM. By utilizing the VLM’s existing visual-linguistic capabilities, OMNI-Dent aims to support diagnostic assessment in settings where curated clinical imaging is unavailable. Designed as an early-stage assistive tool, OMNI-Dent helps users identify potential abnormalities and determine when professional evaluation may be needed, offering a practical option for individuals with limited access to in-person care.
[207] Toward Accurate and Accessible Markerless Neuronavigation
Ziye Xie, Oded Schlesinger, Raj Kundu, Jessica Y. Choi, Pablo Iturralde, Dennis A. Turner, Stefan M. Goetz, Guillermo Sapiro, Angel V. Peterchev, J. Matias Di Martino
Main category: cs.CV
TL;DR: Markerless neuronavigation using low-cost visible/IR cameras with stereo/depth sensing replaces traditional marker-based systems, achieving 2.32mm/2.01° accuracy comparable to conventional methods.
Details
Motivation: Traditional neuronavigation systems rely on subject-mounted markers that require manual registration, may shift during procedures, cause discomfort, and use expensive hardware. There's a need for more accessible, comfortable, and cost-effective alternatives.Method: Proposes markerless approaches using low-cost visible and infrared light cameras with stereo and depth sensing, combined with algorithmic modeling of facial geometry to track head position without physical markers.
Result: Validation with 50 human subjects showed median tracking discrepancy of 2.32mm and 2.01° for best markerless algorithms, comparable to conventional marker-based systems and substantially better than prior markerless results.
Conclusion: Markerless neuronavigation can reduce setup cost/complexity, improve patient comfort, and expand access to neuronavigation in clinical/research settings, with potential for further accuracy improvements through sensor fusion.
Abstract: Neuronavigation is widely used in biomedical research and interventions to guide the precise placement of instruments around the head to support procedures such as transcranial magnetic stimulation. Traditional systems, however, rely on subject-mounted markers that require manual registration, may shift during procedures, and can cause discomfort. We introduce and evaluate markerless approaches that replace expensive hardware and physical markers with low-cost visible and infrared light cameras incorporating stereo and depth sensing combined with algorithmic modeling of the facial geometry. Validation with $50$ human subjects yielded a median tracking discrepancy of only $2.32$ mm and $2.01°$ for the best markerless algorithms compared to a conventional marker-based system, which indicates sufficient accuracy for transcranial magnetic stimulation and a substantial improvement over prior markerless results. The results suggest that integration of the data from the various camera sensors can improve the overall accuracy further. The proposed markerless neuronavigation methods can reduce setup cost and complexity, improve patient comfort, and expand access to neuronavigation in clinical and research settings.
[208] COMBOOD: A Semiparametric Approach for Detecting Out-of-distribution Data for Image Classification
Magesh Rajasekaran, Md Saiful Islam Sajol, Frej Berglind, Supratik Mukhopadhyay, Kamalika Das
Main category: cs.CV
TL;DR: COMBOOD: A semi-parametric framework combining nearest-neighbor and Mahalanobis distance metrics for accurate out-of-distribution detection in image recognition, performing well on both near-OOD and far-OOD scenarios.
Details
Motivation: Current OOD detection methods have limitations - nearest-neighbor approaches work well non-parametrically but Mahalanobis distance methods, while effective for far-OOD scenarios, underperform in near-OOD situations that are common in practical applications.Method: COMBOOD combines signals from two distance metrics: nearest-neighbor (non-parametric) and Mahalanobis distance (parametric). The framework operates in a semi-parametric setting to derive a confidence score for OOD detection, scaling linearly with embedding space size.
Result: COMBOOD outperforms state-of-the-art OOD detection methods on OpenOOD benchmarks (v1 and v1.5) for both far-OOD and near-OOD scenarios, as well as on document datasets. Improvements are statistically significant on most benchmark datasets.
Conclusion: The COMBOOD framework provides an effective solution for OOD detection that works well across both near and far OOD scenarios, making it suitable for real-world applications due to its linear scaling and strong performance.
Abstract: Identifying out-of-distribution (OOD) data at inference time is crucial for many machine learning applications, especially for automation. We present a novel unsupervised semi-parametric framework COMBOOD for OOD detection with respect to image recognition. Our framework combines signals from two distance metrics, nearest-neighbor and Mahalanobis, to derive a confidence score for an inference point to be out-of-distribution. The former provides a non-parametric approach to OOD detection. The latter provides a parametric, simple, yet effective method for detecting OOD data points, especially, in the far OOD scenario, where the inference point is far apart from the training data set in the embedding space. However, its performance is not satisfactory in the near OOD scenarios that arise in practical situations. Our COMBOOD framework combines the two signals in a semi-parametric setting to provide a confidence score that is accurate both for the near-OOD and far-OOD scenarios. We show experimental results with the COMBOOD framework for different types of feature extraction strategies. We demonstrate experimentally that COMBOOD outperforms state-of-the-art OOD detection methods on the OpenOOD (both version 1 and most recent version 1.5) benchmark datasets (for both far-OOD and near-OOD) as well as on the documents dataset in terms of accuracy. On a majority of the benchmark datasets, the improvements in accuracy resulting from the COMBOOD framework are statistically significant. COMBOOD scales linearly with the size of the embedding space, making it ideal for many real-life applications.
[209] Fine-Grained Cat Breed Recognition with Global Context Vision Transformer
Mowmita Parvin Hera, Md. Shahriar Mahmud Kallol, Shohanur Rahman Nirob, Md. Badsha Bulbul, Jubayer Ahmed, M. Zhourul Islam, Hazrat Ali, Mohammmad Farhad Bulbul
Main category: cs.CV
TL;DR: Vision Transformer-based approach achieves 92-94% accuracy for cat breed classification using GCViT-Tiny on Oxford-IIIT Pet Dataset with data augmentation.
Details
Motivation: Accurate cat breed identification is challenging due to subtle visual differences, with applications in veterinary diagnostics, animal shelter management, and mobile recognition systems.Method: Used Global Context Vision Transformer (GCViT)-Tiny architecture on Oxford-IIIT Pet Dataset subset with extensive data augmentation (rotation, horizontal flipping, brightness adjustment).
Result: Achieved 92.00% test accuracy and 94.54% validation accuracy, demonstrating transformer effectiveness for fine-grained image classification.
Conclusion: Transformer-based architectures like GCViT are effective for fine-grained visual classification tasks, with practical applications in animal-related domains.
Abstract: Accurate identification of cat breeds from images is a challenging task due to subtle differences in fur patterns, facial structure, and color. In this paper, we present a deep learning-based approach for classifying cat breeds using a subset of the Oxford-IIIT Pet Dataset, which contains high-resolution images of various domestic breeds. We employed the Global Context Vision Transformer (GCViT) architecture-tiny for cat breed recognition. To improve model generalization, we used extensive data augmentation, including rotation, horizontal flipping, and brightness adjustment. Experimental results show that the GCViT-Tiny model achieved a test accuracy of 92.00% and validation accuracy of 94.54%. These findings highlight the effectiveness of transformer-based architectures for fine-grained image classification tasks. Potential applications include veterinary diagnostics, animal shelter management, and mobile-based breed recognition systems. We also provide a hugging face demo at https://huggingface.co/spaces/bfarhad/cat-breed-classifier.
[210] PipeMFL-240K: A Large-scale Dataset and Benchmark for Object Detection in Pipeline Magnetic Flux Leakage Imaging
Tianyi Qu, Songxiao Yang, Haolin Wang, Huadong Song, Xiaoting Guo, Wenguang Hu, Guanlin Liu, Honghe Chen, Yafei Ou
Main category: cs.CV
TL;DR: PipeMFL-240K is a large-scale dataset and benchmark for object detection in pipeline Magnetic Flux Leakage (MFL) pseudo-color images, addressing the lack of public data for automated pipeline integrity assessment.
Details
Motivation: Current deep learning approaches for MFL interpretation lack large-scale public datasets and benchmarks, making fair comparison and reproducible evaluation difficult, which hinders progress toward reliable automated pipeline inspection models.Method: Created PipeMFL-240K dataset with 240,320 images and 191,530 bounding-box annotations from 11 pipelines spanning ~1,480 km, featuring 12 categories with extreme long-tailed distribution, tiny objects, and high intra-class variability.
Result: Extensive experiments with state-of-the-art object detectors show they still struggle with MFL data’s intrinsic properties, indicating considerable room for improvement, while PipeMFL-240K provides a reliable testbed for future research.
Conclusion: PipeMFL-240K is the first public dataset and benchmark of this scale for pipeline MFL inspection, providing a critical foundation for efficient pipeline diagnostics and maintenance planning, expected to accelerate algorithmic innovation in pipeline integrity assessment.
Abstract: Pipeline integrity is critical to industrial safety and environmental protection, with Magnetic Flux Leakage (MFL) detection being a primary non-destructive testing technology. Despite the promise of deep learning for automating MFL interpretation, progress toward reliable models has been constrained by the absence of a large-scale public dataset and benchmark, making fair comparison and reproducible evaluation difficult. We introduce \textbf{PipeMFL-240K}, a large-scale, meticulously annotated dataset and benchmark for complex object detection in pipeline MFL pseudo-color images. PipeMFL-240K reflects real-world inspection complexity and poses several unique challenges: (i) an extremely long-tailed distribution over \textbf{12} categories, (ii) a high prevalence of tiny objects that often comprise only a handful of pixels, and (iii) substantial intra-class variability. The dataset contains \textbf{240,320} images and \textbf{191,530} high-quality bounding-box annotations, collected from 11 pipelines spanning approximately \textbf{1,480} km. Extensive experiments are conducted with state-of-the-art object detectors to establish baselines. Results show that modern detectors still struggle with the intrinsic properties of MFL data, highlighting considerable headroom for improvement, while PipeMFL-240K provides a reliable and challenging testbed to drive future research. As the first public dataset and the first benchmark of this scale and scope for pipeline MFL inspection, it provides a critical foundation for efficient pipeline diagnostics as well as maintenance planning and is expected to accelerate algorithmic innovation and reproducible research in MFL-based pipeline integrity assessment.
[211] VLRS-Bench: A Vision-Language Reasoning Benchmark for Remote Sensing
Zhiming Luo, Di Wang, Haonan Guo, Jing Zhang, Bo Du
Main category: cs.CV
TL;DR: VLRS-Bench is the first benchmark dedicated to complex reasoning in remote sensing, addressing the perception bias in existing RS benchmarks by focusing on cognition, decision, and prediction tasks.
Details
Motivation: Existing remote sensing benchmarks are heavily biased toward perception tasks (object recognition, scene classification), which hinders the development of MLLMs for cognitively demanding RS applications that require complex reasoning.Method: Proposed Vision Language ReaSoning Benchmark (VLRS-Bench) with 2,000 question-answer pairs across 14 tasks and up to eight temporal phases, structured around three core dimensions: Cognition, Decision, and Prediction. Constructed via specialized pipeline integrating RS-specific priors and expert knowledge.
Result: Experimental results reveal significant bottlenecks in existing state-of-the-art MLLMs, providing critical insights for advancing multimodal reasoning within the remote sensing community.
Conclusion: VLRS-Bench addresses the gap in RS benchmarks by focusing on complex reasoning tasks, enabling better evaluation and development of MLLMs for advanced remote sensing applications.
Abstract: Recent advancements in Multimodal Large Language Models (MLLMs) have enabled complex reasoning. However, existing remote sensing (RS) benchmarks remain heavily biased toward perception tasks, such as object recognition and scene classification. This limitation hinders the development of MLLMs for cognitively demanding RS applications. To address this, , we propose a Vision Language ReaSoning Benchmark (VLRS-Bench), which is the first benchmark exclusively dedicated to complex RS reasoning. Structured across the three core dimensions of Cognition, Decision, and Prediction, VLRS-Bench comprises 2,000 question-answer pairs with an average length of 71 words, spanning 14 tasks and up to eight temporal phases. VLRS-Bench is constructed via a specialized pipeline that integrates RS-specific priors and expert knowledge to ensure geospatial realism and reasoning complexity. Experimental results reveal significant bottlenecks in existing state-of-the-art MLLMs, providing critical insights for advancing multimodal reasoning within the remote sensing community.
[212] ShapBPT: Image Feature Attributions Using Data-Aware Binary Partition Trees
Muhammad Rashid, Elvio G. Amparore, Enrico Ferrari, Damiano Verda
Main category: cs.CV
TL;DR: ShapBPT introduces a data-aware hierarchical Shapley method for computer vision interpretability that uses Binary Partition Trees to align feature attributions with image morphology.
Details
Motivation: Existing hierarchical Shapley methods don't exploit image multiscale structure, leading to slow convergence and poor alignment with actual morphological features. There's a gap in using data-aware hierarchies for computer vision interpretability.Method: ShapBPT assigns Shapley coefficients to a multiscale hierarchical structure called Binary Partition Tree (BPT), which is tailored for images. This data-aware hierarchical partitioning aligns feature attributions with intrinsic image morphology.
Result: Experimental results show superior alignment with image structures, improved efficiency over existing XCV methods, and a 20-subject user study confirms human preference for ShapBPT explanations.
Conclusion: ShapBPT connects hierarchical Shapley methods with image data, providing more efficient and semantically meaningful visual interpretability for computer vision models.
Abstract: Pixel-level feature attributions are an important tool in eXplainable AI for Computer Vision (XCV), providing visual insights into how image features influence model predictions. The Owen formula for hierarchical Shapley values has been widely used to interpret machine learning (ML) models and their learned representations. However, existing hierarchical Shapley approaches do not exploit the multiscale structure of image data, leading to slow convergence and weak alignment with the actual morphological features. Moreover, no prior Shapley method has leveraged data-aware hierarchies for Computer Vision tasks, leaving a gap in model interpretability of structured visual data. To address this, this paper introduces ShapBPT, a novel data-aware XCV method based on the hierarchical Shapley formula. ShapBPT assigns Shapley coefficients to a multiscale hierarchical structure tailored for images, the Binary Partition Tree (BPT). By using this data-aware hierarchical partitioning, ShapBPT ensures that feature attributions align with intrinsic image morphology, effectively prioritizing relevant regions while reducing computational overhead. This advancement connects hierarchical Shapley methods with image data, providing a more efficient and semantically meaningful approach to visual interpretability. Experimental results confirm ShapBPT’s effectiveness, demonstrating superior alignment with image structures and improved efficiency over existing XCV methods, and a 20-subject user study confirming that ShapBPT explanations are preferred by humans.
[213] Enhancing IMU-Based Online Handwriting Recognition via Contrastive Learning with Zero Inference Overhead
Jindong Li, Dario Zanca, Vincent Christlein, Tim Hamann, Jens Barth, Peter Kämpf, Björn Eskofier
Main category: cs.CV
TL;DR: ECHWR is a training framework for edge-based online handwriting recognition using IMU sensors that improves accuracy without increasing inference costs through error-enhanced contrastive learning.
Details
Motivation: Edge-based handwriting recognition from IMU sensors offers privacy and low latency benefits but faces memory constraints. Existing methods struggle to improve accuracy without increasing model complexity and inference costs.Method: Proposes Error-enhanced Contrastive Handwriting Recognition (ECHWR) with a temporary auxiliary branch during training that aligns sensor signals with text embeddings using dual contrastive objectives: in-batch contrastive loss for modality alignment and novel error-based contrastive loss distinguishing correct signals from synthetic hard negatives.
Result: On OnHW-Words500 dataset, ECHWR reduces character error rates by up to 7.4% on writer-independent split and 10.4% on writer-dependent split compared to state-of-the-art baselines, while maintaining original efficient architecture at inference.
Conclusion: ECHWR effectively improves handwriting recognition accuracy for edge devices without increasing inference costs, with error-based contrastive loss proving particularly effective for handling unseen writing styles.
Abstract: Online handwriting recognition using inertial measurement units opens up handwriting on paper as input for digital devices. Doing it on edge hardware improves privacy and lowers latency, but entails memory constraints. To address this, we propose Error-enhanced Contrastive Handwriting Recognition (ECHWR), a training framework designed to improve feature representation and recognition accuracy without increasing inference costs. ECHWR utilizes a temporary auxiliary branch that aligns sensor signals with semantic text embeddings during the training phase. This alignment is maintained through a dual contrastive objective: an in-batch contrastive loss for general modality alignment and a novel error-based contrastive loss that distinguishes between correct signals and synthetic hard negatives. The auxiliary branch is discarded after training, which allows the deployed model to keep its original, efficient architecture. Evaluations on the OnHW-Words500 dataset show that ECHWR significantly outperforms state-of-the-art baselines, reducing character error rates by up to 7.4% on the writer-independent split and 10.4% on the writer-dependent split. Finally, although our ablation studies indicate that solving specific challenges require specific architectural and objective configurations, error-based contrastive loss shows its effectiveness for handling unseen writing styles.
[214] Interpreting Physics in Video World Models
Sonia Joseph, Quentin Garrido, Randall Balestriero, Matthew Kowal, Thomas Fel, Shahab Bakhtiari, Blake Richards, Mike Rabbat
Main category: cs.CV
TL;DR: Video transformers encode physical variables in distributed representations rather than factorized ones, with a Physics Emergence Zone where direction information becomes accessible through high-dimensional circular geometry.
Details
Motivation: To understand whether video-based models use factorized representations of physical variables (like classical physics engines) or distributed representations for physical reasoning, and to characterize where and how physical information is organized within video transformers.Method: Used interpretability techniques including layerwise probing, subspace geometry analysis, patch-level decoding, and targeted attention ablations on large-scale video encoders to examine physical representations.
Result: Identified a Physics Emergence Zone at intermediate depths where physical variables become accessible. Scalar quantities (speed, acceleration) are available early, while motion direction becomes accessible only at this zone through high-dimensional population structures with circular geometry.
Conclusion: Modern video models use distributed rather than factorized representations of physical variables, which are nonetheless sufficient for making physical predictions, challenging classical physics engine approaches.
Abstract: A long-standing question in physical reasoning is whether video-based models need to rely on factorized representations of physical variables in order to make physically accurate predictions, or whether they can implicitly represent such variables in a task-specific, distributed manner. While modern video world models achieve strong performance on intuitive physics benchmarks, it remains unclear which of these representational regimes they implement internally. Here, we present the first interpretability study to directly examine physical representations inside large-scale video encoders. Using layerwise probing, subspace geometry, patch-level decoding, and targeted attention ablations, we characterize where physical information becomes accessible and how it is organized within encoder-based video transformers. Across architectures, we identify a sharp intermediate-depth transition – which we call the Physics Emergence Zone – at which physical variables become accessible. Physics-related representations peak shortly after this transition and degrade toward the output layers. Decomposing motion into explicit variables, we find that scalar quantities such as speed and acceleration are available from early layers onwards, whereas motion direction becomes accessible only at the Physics Emergence Zone. Notably, we find that direction is encoded through a high-dimensional population structure with circular geometry, requiring coordinated multi-feature intervention to control. These findings suggest that modern video models do not use factorized representations of physical variables like a classical physics engine. Instead, they use a distributed representation that is nonetheless sufficient for making physical predictions.
[215] Neural Sentinel: Unified Vision Language Model (VLM) for License Plate Recognition with Human-in-the-Loop Continual Learning
Karthik Sivakoti
Main category: cs.CV
TL;DR: Neural Sentinel: A unified VLM approach for license plate recognition and vehicle analysis using fine-tuned PaliGemma 3B with LoRA adaptation, achieving 92.3% accuracy and zero-shot generalization to auxiliary tasks.
Details
Motivation: Traditional ALPR systems use multi-stage pipelines with separate detection and OCR modules, leading to compounding errors, increased latency, and architectural complexity. The authors aim to create a unified approach using VLMs.Method: Fine-tuned PaliGemma 3B model with Low-Rank Adaptation (LoRA) to perform license plate recognition, state classification, and vehicle attribute extraction in a single forward pass. Includes Human-in-the-Loop continual learning with experience replay (70:30 original:correction ratio).
Result: Achieved 92.3% plate recognition accuracy (14.1% improvement over EasyOCR, 9.9% over PaddleOCR), 152ms mean inference latency, ECE of 0.048. Zero-shot generalization to vehicle color detection (89%), seatbelt detection (82%), and occupancy counting (78%).
Conclusion: Unified vision-language approaches represent a paradigm shift in ALPR systems, offering superior accuracy, reduced complexity, and emergent multi-task capabilities that traditional pipelines cannot achieve.
Abstract: Traditional Automatic License Plate Recognition (ALPR) systems employ multi-stage pipelines consisting of object detection networks followed by separate Optical Character Recognition (OCR) modules, introducing compounding errors, increased latency, and architectural complexity. This research presents Neural Sentinel, a novel unified approach that leverages Vision Language Models (VLMs) to perform license plate recognition, state classification, and vehicle attribute extraction through a single forward pass. Our primary contribution lies in demonstrating that a fine-tuned PaliGemma 3B model, adapted via Low-Rank Adaptation (LoRA), can simultaneously answer multiple visual questions about vehicle images, achieving 92.3% plate recognition accuracy, which is a 14.1% improvement over EasyOCR and 9.9% improvement over PaddleOCR baselines. We introduce a Human-in-the-Loop (HITL) continual learning framework that incorporates user corrections while preventing catastrophic forgetting through experience replay, maintaining a 70:30 ratio of original training data to correction samples. The system achieves a mean inference latency of 152ms with an Expected Calibration Error (ECE) of 0.048, indicating well calibrated confidence estimates. Additionally, the VLM first architecture enables zero-shot generalization to auxiliary tasks including vehicle color detection (89%), seatbelt detection (82%), and occupancy counting (78%) without task specific training. Through extensive experimentation on real world toll plaza imagery, we demonstrate that unified vision language approaches represent a paradigm shift in ALPR systems, offering superior accuracy, reduced architectural complexity, and emergent multi-task capabilities that traditional pipeline approaches cannot achieve.
[216] RECITYGEN – Interactive and Generative Participatory Urban Design Tool with Latent Diffusion and Segment Anything
Di Mo, Mingyang Sun, Chengxiu Yin, Runjia Tian, Yanhong Wu, Liyan Xu
Main category: cs.CV
TL;DR: RECITYGEN is an interactive urban design tool that combines latent diffusion models with semantic segmentation to generate street view variations based on text prompts, enabling participatory urban planning.
Details
Motivation: Traditional top-down urban design methods often exclude public input, creating a gap between design aspirations and reality. The authors aim to leverage recent advances in deep learning and digital tools to enable more participatory urban design processes.Method: Combines state-of-the-art latent diffusion models with interactive semantic segmentation to create RECITYGEN, a tool that allows users to interactively generate variational street view images of urban environments using text prompts.
Result: In a pilot project in Beijing, users successfully employed RECITYGEN to suggest improvements for an ongoing Urban Regeneration project. The tool demonstrated significant potential in aligning with public preferences despite some limitations.
Conclusion: RECITYGEN represents a shift towards more dynamic and inclusive urban planning methods by enabling public participation through AI-powered visual generation tools.
Abstract: Urban design profoundly impacts public spaces and community engagement. Traditional top-down methods often overlook public input, creating a gap in design aspirations and reality. Recent advancements in digital tools, like City Information Modelling and augmented reality, have enabled a more participatory process involving more stakeholders in urban design. Further, deep learning and latent diffusion models have lowered barriers for design generation, providing even more opportunities for participatory urban design. Combining state-of-the-art latent diffusion models with interactive semantic segmentation, we propose RECITYGEN, a novel tool that allows users to interactively create variational street view images of urban environments using text prompts. In a pilot project in Beijing, users employed RECITYGEN to suggest improvements for an ongoing Urban Regeneration project. Despite some limitations, RECITYGEN has shown significant potential in aligning with public preferences, indicating a shift towards more dynamic and inclusive urban planning methods. The source code for the project can be found at RECITYGEN GitHub.
[217] FADE: Selective Forgetting via Sparse LoRA and Self-Distillation
Carolina R. Kelsch, Leonardo S. B. Pereira, Natnael Mola, Luis H. Arribas, Juan C. S. M. Avedillo
Main category: cs.CV
TL;DR: FADE is a two-stage unlearning method for text-to-image diffusion models that uses gradient-based saliency to identify key parameters, applies sparse LoRA adapters for localized modifications, and uses self-distillation to overwrite forgotten concepts with user-defined surrogates while preserving performance on retained data.
Details
Motivation: Machine unlearning is increasingly required by data protection regulations and responsible AI practices, but unlearning in text-to-image diffusion models remains challenging due to high computational costs and difficulty balancing effective forgetting with retention of unrelated concepts.Method: Two-stage approach: 1) Identify parameters most responsible for forget set using gradient-based saliency and constrain updates through sparse LoRA adapters for lightweight, localized modifications. 2) Apply self-distillation objective that overwrites forgotten concept with user-defined surrogate while preserving behavior on retained data.
Result: Achieves state-of-the-art unlearning performance on UnlearnCanvas benchmark and ablation studies across multiple datasets (Imagenette, LFW, Dog Breeds, SUN Attributes), demonstrating strong concept erasure and high retainability with fine-grained control over forgetting-retention trade-off.
Conclusion: FADE provides memory-efficient, reversible adapters that can be merged or removed at runtime, enabling flexible deployment in production systems for selective unlearning in diffusion-based image generation models.
Abstract: Machine Unlearning aims to remove the influence of specific data or concepts from trained models while preserving overall performance, a capability increasingly required by data protection regulations and responsible AI practices. Despite recent progress, unlearning in text-to-image diffusion models remains challenging due to high computational costs and the difficulty of balancing effective forgetting with retention of unrelated concepts. We introduce FADE (Fast Adapter for Data Erasure), a two-stage unlearning method for image generation that combines parameter localization with self-distillation. FADE first identifies parameters most responsible for the forget set using gradient-based saliency and constrains updates through sparse LoRA adapters, ensuring lightweight, localized modifications. In a second stage, FADE applies a self-distillation objective that overwrites the forgotten concept with a user-defined surrogate while preserving behavior on retained data. The resulting adapters are memory-efficient, reversible, and can be merged or removed at runtime, enabling flexible deployment in production systems. We evaluated FADE on the UnlearnCanvas benchmark and conducted ablation studies on Imagenette, Labeled Faces in the Wild, AtharvaTaras Dog Breeds Dataset, and SUN Attributes datasets, demonstrating State-of-the-Art unlearning performance with fine-grained control over the forgetting-retention trade-off. Our results demonstrate that FADE achieves strong concept erasure and high retainability across various domains, making it a suitable solution for selective unlearning in diffusion-based image generation models.
[218] From Images to Decisions: Assistive Computer Vision for Non-Metallic Content Estimation in Scrap Metal
Daniil Storonkin, Ilia Dziub, Maksim Golyadkin, Ilya Makarov
Main category: cs.CV
TL;DR: Computer vision pipeline for estimating scrap contamination percentage and classifying scrap type in steelmaking using multi-instance learning and multi-task learning from railcar unloading images.
Details
Motivation: Current visual inspection of scrap quality in steelmaking is subjective, hazardous, and affects energy use, emissions, and safety. Need for objective, automated assessment system.Method: Formulates contamination assessment as regression task using multi-instance learning (MIL) for sequential data and multi-task learning (MTL) for joint contamination estimation and scrap classification. Implements near real-time system with magnet/railcar detection, versioned inference service, and active-learning loop.
Result: Best results: MAE 0.27 and R² 0.83 for contamination estimation using MIL; MTL achieves MAE 0.36 with F1 0.79 for scrap classification. System reduces subjective variability and improves safety.
Conclusion: Computer vision pipeline successfully automates scrap quality assessment, enabling integration into acceptance workflows while supporting continual improvement through active learning.
Abstract: Scrap quality directly affects energy use, emissions, and safety in steelmaking. Today, the share of non-metallic inclusions (contamination) is judged visually by inspectors - an approach that is subjective and hazardous due to dust and moving machinery. We present an assistive computer vision pipeline that estimates contamination (per percent) from images captured during railcar unloading and also classifies scrap type. The method formulates contamination assessment as a regression task at the railcar level and leverages sequential data through multi-instance learning (MIL) and multi-task learning (MTL). Best results include MAE 0.27 and R2 0.83 by MIL; and an MTL setup reaches MAE 0.36 with F1 0.79 for scrap class. Also we present the system in near real time within the acceptance workflow: magnet/railcar detection segments temporal layers, a versioned inference service produces railcar-level estimates with confidence scores, and results are reviewed by operators with structured overrides; corrections and uncertain cases feed an active-learning loop for continual improvement. The pipeline reduces subjective variability, improves human safety, and enables integration into acceptance and melt-planning workflows.
[219] Reproducible Benchmarking for Lung Nodule Detection and Malignancy Classification Across Multiple Low-Dose CT Datasets
Fakrul Islam Tushar, Avivah Wang, Lavsen Dahal, Ehsan Samei, Michael R. Harowicz, Jayashree Kalpathy-Cramer, Kyle J. Lafata, Tina D. Tailor, Cynthia Rudin, Joseph Y. Lo
Main category: cs.CV
TL;DR: A public benchmark for lung nodule detection and cancer classification using multiple CT datasets, showing dataset characteristics strongly influence AI performance and highlighting need for transparent multi-dataset evaluation.
Details
Motivation: Current AI model evaluation for low-dose CT lung cancer screening suffers from heterogeneous datasets, inconsistent annotation standards, and varying evaluation protocols, making performance comparisons and clinical translation difficult across different settings.Method: Established a public multi-dataset benchmark using Duke Lung Cancer Screening (DLCS) as development set, evaluated across LUNA16/LIDC-IDRI, NLST-3D, and LUNA25. For detection: trained models on DLCS and LUNA16, evaluated externally on NLST-3D using free-response ROC analysis. For malignancy classification: compared five strategies including randomly initialized ResNet50, Models Genesis, Med3D, Foundation Model for Cancer Biomarkers, and Strategic Warm-Start (ResNet50-SWS) pretrained using detection-derived candidate patches stratified by confidence.
Result: Detection performance varied substantially by training dataset - DLCS-trained models outperformed LUNA16-trained models on external NLST-3D evaluation (sensitivity at 2 false positives per scan: 0.72 vs. 0.64; p < 0.001). For malignancy classification, ResNet50-SWS achieved AUCs of 0.71 (DLCS), 0.90 (LUNA16), 0.81 (NLST-3D), and 0.80 (LUNA25), consistently matching or exceeding alternative pretraining strategies.
Conclusion: Dataset characteristics strongly influence lung cancer AI performance, highlighting the critical need for transparent, multi-dataset benchmarking to enable reliable performance comparisons and clinical translation across different settings.
Abstract: Evaluation of artificial intelligence (AI) models for low-dose CT lung cancer screening is limited by heterogeneous datasets, annotation standards, and evaluation protocols, making performance difficult to compare and translate across clinical settings. We establish a public, reproducible multi-dataset benchmark for lung nodule detection and nodule-level cancer classification and quantify cross-dataset generalizability. Using the Duke Lung Cancer Screening (DLCS) dataset as a clinically curated development set, we evaluate performance across LUNA16/LIDC-IDRI, NLST-3D, and LUNA25. Detection models trained on DLCS and LUNA16 were evaluated externally on NLST-3D using free-response ROC analysis. For malignancy classification, we compared five strategies: randomly initialized ResNet50, Models Genesis, Med3D, a Foundation Model for Cancer Biomarkers, and a Strategic Warm-Start (ResNet50-SWS) approach pretrained using detection-derived candidate patches stratified by confidence. Performance was summarized using AUC with 95% confidence intervals and DeLong tests. Detection performance varied substantially by training dataset, with DLCS-trained models outperforming LUNA16-trained models on external NLST-3D evaluation (sensitivity at 2 false positives per scan: 0.72 vs. 0.64; p < 0.001). For malignancy classification, ResNet50-SWS achieved AUCs of 0.71 (DLCS), 0.90 (LUNA16), 0.81 (NLST-3D), and 0.80 (LUNA25), consistently matching or exceeding alternative pretraining strategies. These results demonstrate that dataset characteristics strongly influence lung cancer AI performance and highlight the need for transparent, multi-dataset benchmarking.
[220] Exploring Physical Intelligence Emergence via Omni-Modal Architecture and Physical Data Engine
Minghao Han, Dingkang Yang, Yue Jiang, Yizhou Liu, Lihua Zhang
Main category: cs.CV
TL;DR: OmniFysics is a compact omni-modal model that unifies understanding across images, audio, video, and text with integrated speech and image generation, enhanced by explicit physical knowledge injection through a specialized physical data engine.
Details
Motivation: Current omni-modal models have brittle physical understanding because key physical attributes are visually ambiguous and sparsely represented in web-scale data. The authors aim to address this limitation by injecting explicit physical knowledge into multimodal models.Method: 1) Build a physical data engine with two components: FysicsAny (produces physics-grounded instruction-image supervision via hierarchical retrieval over curated prototypes) and FysicsOmniCap (distills web videos via audio-visual consistency filtering). 2) Train OmniFysics with staged multimodal alignment and instruction tuning. 3) Use latent-space flow matching for text-to-image generation. 4) Implement an intent router to activate generation only when needed.
Result: The model shows competitive performance on standard multimodal benchmarks and improved results on physics-oriented evaluations, demonstrating enhanced physical understanding capabilities.
Conclusion: OmniFysics successfully integrates explicit physical knowledge into omni-modal models, addressing the brittleness of physical understanding in current systems while maintaining competitive multimodal performance.
Abstract: Physical understanding remains brittle in omni-modal models because key physical attributes are visually ambiguous and sparsely represented in web-scale data. We present OmniFysics, a compact omni-modal model that unifies understanding across images, audio, video, and text, with integrated speech and image generation. To inject explicit physical knowledge, we build a physical data engine with two components. FysicsAny produces physics-grounded instruction–image supervision by mapping salient objects to verified physical attributes through hierarchical retrieval over a curated prototype database, followed by physics-law–constrained verification and caption rewriting. FysicsOmniCap distills web videos via audio–visual consistency filtering to generate high-fidelity video–instruction pairs emphasizing cross-modal physical cues. We train OmniFysics with staged multimodal alignment and instruction tuning, adopt latent-space flow matching for text-to-image generation, and use an intent router to activate generation only when needed. Experiments show competitive performance on standard multimodal benchmarks and improved results on physics-oriented evaluations.
[221] Training-Free Inference for High-Resolution Sinogram Completion
Jiaze E, Srutarshi Banerjee, Tekin Bicer, Guannan Wang, Yanfu Zhang, Bin Ren
Main category: cs.CV
TL;DR: HRSino is a training-free, efficient diffusion inference approach for high-resolution sinogram completion in CT reconstruction that adaptively allocates inference effort based on spatial heterogeneity rather than using uniform high-resolution diffusion steps.
Details
Motivation: Missing projections in computed tomography can cause severe artifacts, and while diffusion models provide strong generative priors for sinogram completion, their inference cost grows prohibitively with resolution, creating a need for more efficient approaches.Method: HRSino explicitly accounts for spatial heterogeneity in signal characteristics (spectral sparsity and local complexity) to adaptively allocate inference effort across spatial regions and resolutions, capturing global consistency at coarse scales while refining local details only where necessary.
Result: HRSino reduces peak memory usage by up to 30.81% and inference time by up to 17.58% compared to state-of-the-art frameworks while maintaining completion accuracy across datasets and resolutions.
Conclusion: The proposed training-free approach enables efficient high-resolution sinogram completion by adaptively distributing computational resources based on spatial signal characteristics, offering significant efficiency gains without sacrificing accuracy.
Abstract: High-resolution sinogram completion is critical for computed tomography reconstruction, as missing projections can introduce severe artifacts. While diffusion models provide strong generative priors for this task, their inference cost grows prohibitively with resolution. We propose HRSino, a training-free and efficient diffusion inference approach for high-resolution sinogram completion. By explicitly accounting for spatial heterogeneity in signal characteristics, such as spectral sparsity and local complexity, HRSino allocates inference effort adaptively across spatial regions and resolutions, rather than applying uniform high-resolution diffusion steps. This enables global consistency to be captured at coarse scales while refining local details only where necessary. Experimental results show that HRSino reduces peak memory usage by up to 30.81% and inference time by up to 17.58% compared to the state-of-the-art framework, and maintains completion accuracy across datasets and resolutions.
[222] Contactless estimation of continuum displacement and mechanical compressibility from image series using a deep learning based framework
A. N. Maria Antony, T. Richter, E. Gladilin
Main category: cs.CV
TL;DR: Deep learning approach for estimating material compressibility from image series using neural networks for image registration and material property estimation, outperforming conventional methods in efficiency and accuracy.
Details
Motivation: Need for contactless, non-invasive estimation of mechanical properties from optical observations where direct physical measurements are impossible, with conventional methods being too slow and computationally intensive for high-throughput applications.Method: Two-stage deep learning framework: first neural network for image registration to estimate displacement fields, second network for material compressibility estimation from the displacement data, trained end-to-end on reference data.
Result: Deep learning model outperforms conventional approaches in both efficiency and accuracy, can accurately determine material compressibility even with substantial local deviations in displacement field predictions.
Conclusion: The deep learning end-to-end approach is effective for material property estimation from image series, with accuracy stemming from ability to assess higher-order cognitive features like vorticity rather than just local displacement features.
Abstract: Contactless and non-invasive estimation of mechanical properties of physical media from optical observations is of interest for manifold engineering and biomedical applications, where direct physical measurements are not possible. Conventional approaches to the assessment of image displacement and non-contact material probing typically rely on time-consuming iterative algorithms for non-rigid image registration and constitutive modelling using discretization and iterative numerical solving techniques, such as Finite Element Method (FEM) and Finite Difference Method (FDM), which are not suitable for high-throughput data processing. Here, we present an efficient deep learning based end-to-end approach for the estimation of continuum displacement and material compressibility directly from the image series. Based on two deep neural networks for image registration and material compressibility estimation, this framework outperforms conventional approaches in terms of efficiency and accuracy. In particular, our experimental results show that the deep learning model trained on a set of reference data can accurately determine the material compressibility even in the presence of substantial local deviations of the mapping predicted by image registration from the reference displacement field. Our findings suggest that the remarkable accuracy of the deep learning end-to-end model originates from its ability to assess higher-order cognitive features, such as the vorticity of the vector field, rather than conventional local features of the image displacement.
[223] CoBEVMoE: Heterogeneity-aware Feature Fusion with Dynamic Mixture-of-Experts for Collaborative Perception
Lingzhao Kong, Jiacheng Lin, Siyu Li, Kai Luo, Zhiyong Li, Kailun Yang
Main category: cs.CV
TL;DR: CoBEVMoE: A collaborative perception framework using Bird’s Eye View space with Dynamic Mixture-of-Experts to handle heterogeneous observations from multiple agents by modeling both feature similarity and diversity.
Details
Motivation: Current collaborative perception methods focus on aligning similar features but overlook perceptual diversity from different viewpoints and spatial positions of multiple agents, limiting performance with heterogeneous observations.Method: Operates in Bird’s Eye View space with Dynamic Mixture-of-Experts where each expert is dynamically generated based on specific agent’s input features to extract distinctive cues while attending to shared semantics, plus Dynamic Expert Metric Loss for inter-expert diversity.
Result: Achieves state-of-the-art performance: +1.5% IoU for Camera-based BEV segmentation on OPV2V and +3.0% AP@0.5 for LiDAR-based 3D object detection on DAIR-V2X-C datasets.
Conclusion: CoBEVMoE effectively models expert-based heterogeneous features in multi-agent collaborative perception, demonstrating the value of explicitly handling both feature similarity and heterogeneity across agents.
Abstract: Collaborative perception aims to extend sensing coverage and improve perception accuracy by sharing information among multiple agents. However, due to differences in viewpoints and spatial positions, agents often acquire heterogeneous observations. Existing intermediate fusion methods primarily focus on aligning similar features, often overlooking the perceptual diversity among agents. To address this limitation, we propose CoBEVMoE, a novel collaborative perception framework that operates in the Bird’s Eye View (BEV) space and incorporates a Dynamic Mixture-of-Experts (DMoE) architecture. In DMoE, each expert is dynamically generated based on the input features of a specific agent, enabling it to extract distinctive and reliable cues while attending to shared semantics. This design allows the fusion process to explicitly model both feature similarity and heterogeneity across agents. Furthermore, we introduce a Dynamic Expert Metric Loss (DEML) to enhance inter-expert diversity and improve the discriminability of the fused representation. Extensive experiments on the OPV2V and DAIR-V2X-C datasets demonstrate that CoBEVMoE achieves state-of-the-art performance. Specifically, it improves the IoU for Camera-based BEV segmentation by +1.5% on OPV2V and the AP@0.5 for LiDAR-based 3D object detection by +3.0% on DAIR-V2X-C, verifying the effectiveness of expert-based heterogeneous feature modeling in multi-agent collaborative perception. The source code will be made publicly available at https://github.com/godk0509/CoBEVMoE.
[224] Bidirectional Reward-Guided Diffusion for Real-World Image Super-Resolution
Zihao Fan, Xin Lu, Yidi Liu, Jie Huang, Dong Li, Xueyang Fu, Zheng-Jun Zha
Main category: cs.CV
TL;DR: Bird-SR: A bidirectional reward-guided diffusion framework for real-world super-resolution using reward feedback learning to balance structural fidelity and perceptual quality.
Details
Motivation: Diffusion-based super-resolution models trained on synthetic data fail on real-world LR images due to distribution shifts. Need a framework that works on both synthetic and real-world data while preserving structure and enhancing perception.Method: Uses bidirectional reward-guided diffusion with reward feedback learning (ReFL). Early diffusion steps optimize on synthetic pairs for structural fidelity. Later steps apply quality-guided rewards to both synthetic and real images. Mitigates reward hacking via relative advantage space for synthetic results and semantic alignment constraint for real-world optimization. Uses dynamic fidelity-perception weighting strategy.
Result: Extensive experiments on real-world SR benchmarks show Bird-SR consistently outperforms state-of-the-art methods in perceptual quality while preserving structural consistency.
Conclusion: Bird-SR effectively addresses real-world super-resolution by balancing structural preservation and perceptual enhancement through a novel reward-guided diffusion framework.
Abstract: Diffusion-based super-resolution can synthesize rich details, but models trained on synthetic paired data often fail on real-world LR images due to distribution shifts. We propose Bird-SR, a bidirectional reward-guided diffusion framework that formulates super-resolution as trajectory-level preference optimization via reward feedback learning (ReFL), jointly leveraging synthetic LR-HR pairs and real-world LR images. For structural fidelity easily affected in ReFL, the model is directly optimized on synthetic pairs at early diffusion steps, which also facilitates structure preservation for real-world inputs under smaller distribution gap in structure levels. For perceptual enhancement, quality-guided rewards are applied at later sampling steps to both synthetic and real LR images. To mitigate reward hacking, the rewards for synthetic results are formulated in a relative advantage space bounded by their clean counterparts, while real-world optimization is regularized via a semantic alignment constraint. Furthermore, to balance structural and perceptual learning, we adopt a dynamic fidelity-perception weighting strategy that emphasizes structure preservation at early stages and progressively shifts focus toward perceptual optimization at later diffusion steps. Extensive experiments on real-world SR benchmarks demonstrate that Bird-SR consistently outperforms state-of-the-art methods in perceptual quality while preserving structural consistency, validating its effectiveness for real-world super-resolution.
[225] Improving 2D Diffusion Models for 3D Medical Imaging with Inter-Slice Consistent Stochasticity
Chenhe Du, Qing Wu, Xuanyu Tian, Jingyi Yu, Hongjiang Wei, Yuyao Zhang
Main category: cs.CV
TL;DR: ISCS is a plug-and-play method that improves 3D medical imaging reconstruction using 2D diffusion models by controlling inter-slice stochastic noise consistency during sampling, eliminating slice discontinuities without extra training or regularization.
Details
Motivation: 3D medical imaging reconstruction with diffusion models faces challenges: 3D training is computationally expensive, while 2D-trained models produce slice discontinuities due to stochastic sampling noise. Existing regularization methods introduce hyperparameters and can cause over-smoothing.Method: Inter-Slice Consistent Stochasticity (ISCS) controls the consistency of stochastic noise components during diffusion sampling across slices. It aligns sampling trajectories without adding loss terms or optimization steps, making it plug-and-play for any 2D diffusion-based 3D reconstruction pipeline.
Result: Experiments on multiple medical imaging problems show ISCS effectively improves 3D reconstruction performance from 2D diffusion models, reducing inter-slice discontinuities while maintaining image quality.
Conclusion: Controlling inter-slice stochasticity is a principled and practical approach for high-fidelity 3D medical imaging with 2D diffusion priors, offering a computationally efficient solution without additional training costs.
Abstract: 3D medical imaging is in high demand and essential for clinical diagnosis and scientific research. Currently, diffusion models (DMs) have become an effective tool for medical imaging reconstruction thanks to their ability to learn rich, high-quality data priors. However, learning the 3D data distribution with DMs in medical imaging is challenging, not only due to the difficulties in data collection but also because of the significant computational burden during model training. A common compromise is to train the DMs on 2D data priors and reconstruct stacked 2D slices to address 3D medical inverse problems. However, the intrinsic randomness of diffusion sampling causes severe inter-slice discontinuities of reconstructed 3D volumes. Existing methods often enforce continuity regularizations along the z-axis, which introduces sensitive hyper-parameters and may lead to over-smoothing results. In this work, we revisit the origin of stochasticity in diffusion sampling and introduce Inter-Slice Consistent Stochasticity (ISCS), a simple yet effective strategy that encourages interslice consistency during diffusion sampling. Our key idea is to control the consistency of stochastic noise components during diffusion sampling, thereby aligning their sampling trajectories without adding any new loss terms or optimization steps. Importantly, the proposed ISCS is plug-and-play and can be dropped into any 2D trained diffusion based 3D reconstruction pipeline without additional computational cost. Experiments on several medical imaging problems show that our method can effectively improve the performance of medical 3D imaging problems based on 2D diffusion models. Our findings suggest that controlling inter-slice stochasticity is a principled and practically attractive route toward high-fidelity 3D medical imaging with 2D diffusion priors. The code is available at: https://github.com/duchenhe/ISCS
[226] MosaicThinker: On-Device Visual Spatial Reasoning for Embodied AI via Iterative Construction of Space Representation
Haoming Wang, Qiyao Xue, Weichen Liu, Wei Gao
Main category: cs.CV
TL;DR: MosaicThinker enhances on-device small VLMs’ spatial reasoning by integrating multi-frame spatial information into a unified semantic map for cross-frame reasoning tasks.
Details
Motivation: Existing VLMs have weak spatial reasoning capabilities for 3D spatial information, especially for complex spatial relations across multiple video frames, which is crucial for embodied AI tasks like robot manipulation and actuation planning.Method: Proposes MosaicThinker, an inference-time computing technique that integrates fragmented spatial information from multiple frames into a unified global semantic map representation, then guides VLM’s spatial reasoning over this map via visual prompts.
Result: The technique greatly enhances accuracy of cross-frame spatial reasoning on resource-constrained embodied AI devices across diverse reasoning tasks with varying complexities.
Conclusion: MosaicThinker effectively addresses VLMs’ spatial reasoning limitations for embodied AI by creating unified spatial representations from multi-frame inputs, enabling better on-device performance for complex spatial reasoning tasks.
Abstract: When embodied AI is expanding from traditional object detection and recognition to more advanced tasks of robot manipulation and actuation planning, visual spatial reasoning from the video inputs is necessary to perceive the spatial relationships of objects and guide device actions. However, existing visual language models (VLMs) have very weak capabilities in spatial reasoning due to the lack of knowledge about 3D spatial information, especially when the reasoning task involve complex spatial relations across multiple video frames. In this paper, we present a new inference-time computing technique for on-device embodied AI, namely \emph{MosaicThinker}, which enhances the on-device small VLM’s spatial reasoning capabilities on difficult cross-frame reasoning tasks. Our basic idea is to integrate fragmented spatial information from multiple frames into a unified space representation of global semantic map, and further guide the VLM’s spatial reasoning over the semantic map via a visual prompt. Experiment results show that our technique can greatly enhance the accuracy of cross-frame spatial reasoning on resource-constrained embodied AI devices, over reasoning tasks with diverse types and complexities.
[227] WorldEdit: Towards Open-World Image Editing with a Knowledge-Informed Benchmark
Wang Lin, Feng Wang, Majun Zhang, Wentao Hu, Tao Jin, Zhou Zhao, Fei Wu, Jingyuan Chen, Alan Yuille, Sucheng Ren
Main category: cs.CV
TL;DR: WorldEdit introduces a dataset and framework for world-driven image editing that handles implicit instructions requiring real-world causal reasoning, addressing limitations of current models that struggle with complex knowledge-based editing.
Details
Motivation: Current image editing models excel at explicit instructions but fail at implicit editing instructions that require understanding real-world causal logic and complex world knowledge, creating a gap in handling realistic editing scenarios.Method: Created WorldEdit dataset with high-quality editing samples using paraphrased instructions aligned with real-world causal logic, plus WorldEdit-Test for evaluation. Used two-stage training framework fine-tuning models like Bagel with causal verification reward.
Result: Significantly narrows performance gap with GPT-4o and Nano-Banana, showing competitive performance in both instruction following and knowledge plausibility where open-source systems typically struggle.
Conclusion: WorldEdit addresses the critical need for world-driven image editing capabilities, enabling models to handle implicit instructions requiring causal reasoning and complex world knowledge.
Abstract: Recent advances in image editing models have demonstrated remarkable capabilities in executing explicit instructions, such as attribute manipulation, style transfer, and pose synthesis. However, these models often face challenges when dealing with implicit editing instructions, which describe the cause of a visual change without explicitly detailing the resulting outcome. These limitations arise because existing models rely on uniform editing strategies that are not equipped to handle the complex world knowledge and reasoning required for implicit instructions. To address this gap, we introduce \textbf{WorldEdit}, a dataset specifically designed to enable world-driven image editing. WorldEdit consists of high-quality editing samples, guided by paraphrased instructions that align with real-world causal logic. Furthermore, we provide \textbf{WorldEdit-Test} for evaluating the existing model’s performance on causal editing scenarios. With WorldEdit, we use a two-stage training framework for fine-tuning models like Bagel, integrating with a causal verification reward. Our results show that the proposed dataset and methods significantly narrow the gap with GPT-4o and Nano-Banana, demonstrating competitive performance not only in instruction following but also in knowledge plausibility, where many open-source systems typically struggle.
[228] TLC-Plan: A Two-Level Codebook Based Network for End-to-End Vector Floorplan Generation
Biao Xiong, Zhen Peng, Ping Wang, Qiegen Liu, Xian Zhong
Main category: cs.CV
TL;DR: TLC-Plan is a hierarchical generative model that directly synthesizes vector floorplans from input boundaries using a two-level VQ-VAE and autoregressive transformer, achieving state-of-the-art performance on architectural datasets.
Details
Motivation: Existing floorplan generation approaches operate in raster space and rely on post hoc vectorization, which introduces structural inconsistencies and hinders end-to-end learning. The authors aim to develop a method that directly generates vector floorplans, aligning with human architectural workflows based on modular and reusable patterns.Method: Proposes TLC-Plan, a hierarchical generative model using a two-level VQ-VAE: first level encodes global layouts as semantically labeled room bounding boxes, second level refines local geometries using polygon-level codes. This hierarchy is unified in a CodeTree representation, and an autoregressive transformer samples codes conditioned on the boundary to generate diverse and topologically valid designs without requiring explicit room topology or dimensional priors.
Result: Achieves state-of-the-art performance on RPLAN dataset (FID = 1.84, MSE = 2.06) and leading results on LIFULL dataset. The framework advances constraint-aware and scalable vector floorplan generation for real-world architectural applications.
Conclusion: TLC-Plan successfully addresses the limitations of raster-based approaches by directly generating vector floorplans through hierarchical compositional reasoning, demonstrating superior performance and practical applicability for architectural design.
Abstract: Automated floorplan generation aims to improve design quality, architectural efficiency, and sustainability by jointly modeling global spatial organization and precise geometric detail. However, existing approaches operate in raster space and rely on post hoc vectorization, which introduces structural inconsistencies and hinders end-to-end learning. Motivated by compositional spatial reasoning, we propose TLC-Plan, a hierarchical generative model that directly synthesizes vector floorplans from input boundaries, aligning with human architectural workflows based on modular and reusable patterns. TLC-Plan employs a two-level VQ-VAE to encode global layouts as semantically labeled room bounding boxes and to refine local geometries using polygon-level codes. This hierarchy is unified in a CodeTree representation, while an autoregressive transformer samples codes conditioned on the boundary to generate diverse and topologically valid designs, without requiring explicit room topology or dimensional priors. Extensive experiments show state-of-the-art performance on RPLAN dataset (FID = 1.84, MSE = 2.06) and leading results on LIFULL dataset. The proposed framework advances constraint-aware and scalable vector floorplan generation for real-world architectural applications. Source code and trained models are released at https://github.com/rosolose/TLC-PLAN.
[229] Zero-Shot UAV Navigation in Forests via Relightable 3D Gaussian Splatting
Zinan Lv, Yeqian Qian, Chen Sang, Hao Liu, Danping Zou, Ming Yang
Main category: cs.CV
TL;DR: A reinforcement learning framework for UAV navigation using relightable 3D Gaussian Splatting to enable zero-shot transfer to unstructured outdoor environments with dynamic lighting.
Details
Motivation: UAV navigation in unstructured outdoor environments faces challenges due to the visual domain gap between simulation and reality, and existing 3D Gaussian Splatting methods couple static lighting with geometry, limiting policy generalization to dynamic real-world illumination.Method: Proposes an end-to-end reinforcement learning framework with Relightable 3D Gaussian Splatting that decomposes scene components to enable explicit editing of environmental lighting. Trains policies in high-fidelity simulation with diverse synthesized lighting conditions to learn robust, illumination-invariant visual features.
Result: Lightweight quadrotor achieves robust, collision-free navigation in complex forest environments at speeds up to 10 m/s, exhibiting significant resilience to drastic lighting variations without fine-tuning.
Conclusion: The proposed framework enables effective zero-shot transfer to unstructured outdoor environments by addressing photometric limitations through relightable neural representations and diverse lighting augmentation during training.
Abstract: UAV navigation in unstructured outdoor environments using passive monocular vision is hindered by the substantial visual domain gap between simulation and reality. While 3D Gaussian Splatting enables photorealistic scene reconstruction from real-world data, existing methods inherently couple static lighting with geometry, severely limiting policy generalization to dynamic real-world illumination. In this paper, we propose a novel end-to-end reinforcement learning framework designed for effective zero-shot transfer to unstructured outdoors. Within a high-fidelity simulation grounded in real-world data, our policy is trained to map raw monocular RGB observations directly to continuous control commands. To overcome photometric limitations, we introduce Relightable 3D Gaussian Splatting, which decomposes scene components to enable explicit, physically grounded editing of environmental lighting within the neural representation. By augmenting training with diverse synthesized lighting conditions ranging from strong directional sunlight to diffuse overcast skies, we compel the policy to learn robust, illumination-invariant visual features. Extensive real-world experiments demonstrate that a lightweight quadrotor achieves robust, collision-free navigation in complex forest environments at speeds up to 10 m/s, exhibiting significant resilience to drastic lighting variations without fine-tuning.
[230] Extended to Reality: Prompt Injection in 3D Environments
Zhuoheng Li, Ying Chen
Main category: cs.CV
TL;DR: PI3D: A physical prompt injection attack against multimodal LLMs using text-bearing objects in 3D environments to override intended tasks
Details
Motivation: Multimodal LLMs interpreting visual input in 3D environments create new attack surfaces where attackers can place physical objects to override MLLMs' intended tasks, but prior work only studied text-domain and 2D digital image attacksMethod: PI3D formulates and solves the problem of identifying effective 3D object poses (position and orientation) with injected text, ensuring physical plausibility while maximizing attack success
Result: PI3D effectively attacks multiple MLLMs under diverse camera trajectories, and existing defenses are insufficient against it
Conclusion: Physical prompt injection attacks in 3D environments pose a significant security threat to MLLMs, requiring new defense mechanisms beyond current approaches
Abstract: Multimodal large language models (MLLMs) have advanced the capabilities to interpret and act on visual input in 3D environments, empowering diverse applications such as robotics and situated conversational agents. When MLLMs reason over camera-captured views of the physical world, a new attack surface emerges: an attacker can place text-bearing physical objects in the environment to override MLLMs’ intended task. While prior work has studied prompt injection in the text domain and through digitally edited 2D images, it remains unclear how these attacks function in 3D physical environments. To bridge the gap, we introduce PI3D, a prompt injection attack against MLLMs in 3D environments, realized through text-bearing physical object placement rather than digital image edits. We formulate and solve the problem of identifying an effective 3D object pose (position and orientation) with injected text, where the attacker’s goal is to induce the MLLM to perform the injected task while ensuring that the object placement remains physically plausible. Experiments demonstrate that PI3D is an effective attack against multiple MLLMs under diverse camera trajectories. We further evaluate existing defenses and show that they are insufficient to defend against PI3D.
[231] Ex-Omni: Enabling 3D Facial Animation Generation for Omni-modal Large Language Models
Haoyu Zhang, Zhipeng Li, Yiwen Guo, Tianshu Yu
Main category: cs.CV
TL;DR: Ex-Omni is an open-source omni-modal framework that extends multimodal LLMs to generate speech-accompanied 3D facial animation by decoupling semantic reasoning from temporal generation using speech units as temporal scaffolding.
Details
Motivation: Current OLLMs lack integration of speech with 3D facial animation, which is crucial for natural human-computer interaction. The representation mismatch between discrete LLM reasoning and dense temporal motion makes direct modeling difficult with limited data.Method: Decouples semantic reasoning from temporal generation using speech units as temporal scaffolding. Introduces token-as-query gated fusion (TQGF) for controlled semantic injection. Creates InstructEx dataset to train OLLMs for speech-accompanied 3D facial animation.
Result: Ex-Omni performs competitively against existing open-source OLLMs while enabling stable aligned speech and facial animation generation.
Conclusion: Ex-Omni successfully extends OLLMs to incorporate speech with 3D facial animation, addressing the representation mismatch through decoupled learning and temporal scaffolding.
Abstract: Omni-modal large language models (OLLMs) aim to unify multimodal understanding and generation, yet incorporating speech with 3D facial animation remains largely unexplored despite its importance for natural interaction. A key challenge arises from the representation mismatch between discrete, token-level semantic reasoning in LLMs and the dense, fine-grained temporal dynamics required for 3D facial motion, which makes direct modeling difficult to optimize under limited data. We propose Expressive Omni (Ex-Omni), an open-source omni-modal framework that augments OLLMs with speech-accompanied 3D facial animation. Ex-Omni reduces learning difficulty by decoupling semantic reasoning from temporal generation, leveraging speech units as temporal scaffolding and a unified token-as-query gated fusion (TQGF) mechanism for controlled semantic injection. We further introduce InstructEx, a dataset aims to facilitate augment OLLMs with speech-accompanied 3D facial animation. Extensive experiments demonstrate that Ex-Omni performs competitively against existing open-source OLLMs while enabling stable aligned speech and facial animation generation.
[232] Privacy in Image Datasets: A Case Study on Pregnancy Ultrasounds
Rawisara Lohanimit, Yankun Wu, Amelia Katirai, Yuta Nakashima, Noa Garcia
Main category: cs.CV
TL;DR: Systematic analysis reveals pregnancy ultrasound images with sensitive personal information in LAION-400M dataset, highlighting privacy risks and need for better dataset curation practices.
Details
Motivation: The paper addresses privacy concerns in large-scale internet-collected datasets used for generative models, focusing on sensitive pregnancy ultrasound images that contain personal information often shared online without proper curation.Method: Used CLIP embedding similarity to systematically examine LAION-400M dataset, retrieving pregnancy ultrasound images and detecting thousands of entities containing private information like names and locations.
Result: Found multiple images with high-risk information enabling re-identification or impersonation, demonstrating significant privacy vulnerabilities in widely used public datasets.
Conclusion: Recommends improved practices for dataset curation, data privacy, and ethical use of public image datasets to address privacy risks in multimodal AI systems.
Abstract: The rise of generative models has led to increased use of large-scale datasets collected from the internet, often with minimal or no data curation. This raises concerns about the inclusion of sensitive or private information. In this work, we explore the presence of pregnancy ultrasound images, which contain sensitive personal information and are often shared online. Through a systematic examination of LAION-400M dataset using CLIP embedding similarity, we retrieve images containing pregnancy ultrasound and detect thousands of entities of private information such as names and locations. Our findings reveal that multiple images have high-risk information that could enable re-identification or impersonation. We conclude with recommended practices for dataset curation, data privacy, and ethical use of public image datasets.
[233] DuMeta++: Spatiotemporal Dual Meta-Learning for Generalizable Few-Shot Brain Tissue Segmentation Across Diverse Ages
Yongheng Sun, Jun Shu, Jianhua Ma, Fan Wang
Main category: cs.CV
TL;DR: DuMeta++ is a dual meta-learning framework for brain MRI segmentation that achieves consistent performance across the human lifespan without requiring paired longitudinal data.
Details
Motivation: Brain tissue segmentation from MRI scans is crucial for neuroscience and clinical applications, but existing methods struggle with age-related appearance and morphology changes. While self-supervised regularization with paired longitudinal data helps, such data is often unavailable in practice.Method: Proposes a dual meta-learning framework with: (1) meta-feature learning to extract age-agnostic semantic representations of evolving brain structures, (2) meta-initialization learning for data-efficient adaptation, and (3) memory-bank-based class-aware regularization for longitudinal consistency without explicit supervision.
Result: Experiments on diverse datasets (iSeg-2019, IBIS, OASIS, ADNI) under few-shot settings demonstrate that DuMeta++ outperforms existing methods in cross-age generalization.
Conclusion: DuMeta++ effectively addresses the challenge of brain tissue segmentation across the lifespan without requiring paired longitudinal data, achieving superior cross-age generalization through its dual meta-learning approach.
Abstract: Accurate segmentation of brain tissues from MRI scans is critical for neuroscience and clinical applications, but achieving consistent performance across the human lifespan remains challenging due to dynamic, age-related changes in brain appearance and morphology. While prior work has sought to mitigate these shifts by using self-supervised regularization with paired longitudinal data, such data are often unavailable in practice. To address this, we propose \emph{DuMeta++}, a dual meta-learning framework that operates without paired longitudinal data. Our approach integrates: (1) meta-feature learning to extract age-agnostic semantic representations of spatiotemporally evolving brain structures, and (2) meta-initialization learning to enable data-efficient adaptation of the segmentation model. Furthermore, we propose a memory-bank-based class-aware regularization strategy to enforce longitudinal consistency without explicit longitudinal supervision. We theoretically prove the convergence of our DuMeta++, ensuring stability. Experiments on diverse datasets (iSeg-2019, IBIS, OASIS, ADNI) under few-shot settings demonstrate that DuMeta++ outperforms existing methods in cross-age generalization. Code will be available at https://github.com/ladderlab-xjtu/DuMeta++.
[234] Condition Matters in Full-head 3D GANs
Heyuan Li, Huimin Zhang, Yuda Qiu, Zhengwentai Sun, Keru Zheng, Lingteng Qiu, Peihao Li, Qi Zuo, Ce Chen, Yujian Zheng, Yuming Gu, Zilong Dong, Xiaoguang Han
Main category: cs.CV
TL;DR: Proposes view-invariant semantic conditioning for 3D GANs to address view-direction bias and improve full-head 3D generation coherence and diversity.
Details
Motivation: Traditional 3D GANs use view angle conditioning which creates bias along conditional view direction, leading to quality/diversity disparities between conditional vs non-conditional views and global incoherence in generated 3D heads.Method: Uses view-invariant semantic features as conditioning input instead of view angles. Creates synthesized head image dataset using FLUX.1 Kontext to extend frontal face datasets to multiple views. Uses frontal view image clip features as shared semantic condition across all views, enabling semantic alignment and eliminating directional bias.
Result: Achieves significantly higher fidelity, diversity, and generalizability in full-head synthesis and single-view GAN inversion compared to previous methods. Improves global coherence of generated 3D heads and accelerates training.
Conclusion: Semantic conditioning decouples generative capability from viewing direction, promotes continuous learning, and enhances 3D head generation quality and diversity by following true semantic distribution rather than view-dependent patterns.
Abstract: Conditioning is crucial for stable training of full-head 3D GANs. Without any conditioning signal, the model suffers from severe mode collapse, making it impractical to training. However, a series of previous full-head 3D GANs conventionally choose the view angle as the conditioning input, which leads to a bias in the learned 3D full-head space along the conditional view direction. This is evident in the significant differences in generation quality and diversity between the conditional view and non-conditional views of the generated 3D heads, resulting in global incoherence across different head regions. In this work, we propose to use view-invariant semantic feature as the conditioning input, thereby decoupling the generative capability of 3D heads from the viewing direction. To construct a view-invariant semantic condition for each training image, we create a novel synthesized head image dataset. We leverage FLUX.1 Kontext to extend existing high-quality frontal face datasets to a wide range of view angles. The image clip feature extracted from the frontal view is then used as a shared semantic condition across all views in the extended images, ensuring semantic alignment while eliminating directional bias. This also allows supervision from different views of the same subject to be consolidated under a shared semantic condition, which accelerates training and enhances the global coherence of the generated 3D heads. Moreover, as GANs often experience slower improvements in diversity once the generator learns a few modes that successfully fool the discriminator, our semantic conditioning encourages the generator to follow the true semantic distribution, thereby promoting continuous learning and diverse generation. Extensive experiments on full-head synthesis and single-view GAN inversion demonstrate that our method achieves significantly higher fidelity, diversity, and generalizability.
[235] Understanding Real-World Traffic Safety through RoadSafe365 Benchmark
Xinyu Liu, Darryl C. Jacob, Yuxin Liu, Xinsong Du, Muchao Ye, Bolei Zhou, Pan He
Main category: cs.CV
TL;DR: RoadSafe365 is a large-scale vision-language benchmark for traffic safety analysis that bridges official safety standards with data-driven systems through hierarchical taxonomy and rich annotations.
Details
Motivation: Existing traffic benchmarks lack systematic evaluation aligned with official safety standards and focus primarily on coarse accident identification, creating a gap for fine-grained traffic safety analysis.Method: Created RoadSafe365 with hierarchical taxonomy refining crash, incident, and violation definitions; annotated 36,196 clips from dashcam/surveillance cameras with multiple-choice QA sets, scene descriptions, and diverse attributes.
Result: Established strong baselines with consistent gains when fine-tuning on RoadSafe365; cross-domain experiments on real and synthetic datasets validated effectiveness; created comprehensive benchmark with 864K candidate options and 8.4K unique answers.
Conclusion: RoadSafe365 provides a comprehensive benchmark for reproducible research in real-world traffic safety analysis, designed for large-scale training and standardized evaluation.
Abstract: Although recent traffic benchmarks have advanced multimodal data analysis, they generally lack systematic evaluation aligned with official safety standards. To fill this gap, we introduce RoadSafe365, a large-scale vision-language benchmark that supports fine-grained analysis of traffic safety from extensive and diverse real-world video data collections. Unlike prior works that focus primarily on coarse accident identification, RoadSafe365 is independently curated and systematically organized using a hierarchical taxonomy that refines and extends foundational definitions of crash, incident, and violation to bridge official traffic safety standards with data-driven traffic understanding systems. RoadSafe365 provides rich attribute annotations across diverse traffic event types, environmental contexts, and interaction scenarios, yielding 36,196 annotated clips from both dashcam and surveillance cameras. Each clip is paired with multiple-choice question-answer sets, comprising 864K candidate options, 8.4K unique answers, and 36K detailed scene descriptions collectively designed for vision-language understanding and reasoning. We establish strong baselines and observe consistent gains when fine-tuning on RoadSafe365. Cross-domain experiments on both real and synthetic datasets further validate its effectiveness. Designed for large-scale training and standardized evaluation, RoadSafe365 provides a comprehensive benchmark to advance reproducible research in real-world traffic safety analysis.
[236] The Double-Edged Sword of Data-Driven Super-Resolution: Adversarial Super-Resolution Models
Haley Duba-Sullivan, Steven R. Young, Emma J. Reid
Main category: cs.CV
TL;DR: AdvSR embeds adversarial behavior directly into super-resolution model weights during training, creating models that appear benign but cause downstream misclassification without input manipulation at inference time.
Details
Motivation: Super-resolution models are commonly used as preprocessing steps in imaging pipelines, but they introduce an unexplored attack surface. The authors aim to demonstrate that adversarial behavior can be embedded directly into model weights, creating a new model-level threat that doesn't require input manipulation at inference time.Method: AdvSR framework jointly optimizes for both reconstruction quality and targeted adversarial outcomes during training. The approach embeds adversarial behavior directly into SR model weights, requiring no access to inputs at inference time. The method was evaluated on three SR architectures (SRCNN, EDSR, SwinIR) paired with a YOLOv11 classifier.
Result: AdvSR models achieve high attack success rates with minimal quality degradation. The models appear benign under standard image quality metrics while effectively inducing downstream misclassification in the paired classifier.
Conclusion: The work reveals a new model-level threat for imaging pipelines that use SR preprocessing, highlighting security implications for how practitioners source and validate models in safety-critical applications.
Abstract: Data-driven super-resolution (SR) methods are often integrated into imaging pipelines as preprocessing steps to improve downstream tasks such as classification and detection. However, these SR models introduce a previously unexplored attack surface into imaging pipelines. In this paper, we present AdvSR, a framework demonstrating that adversarial behavior can be embedded directly into SR model weights during training, requiring no access to inputs at inference time. Unlike prior attacks that perturb inputs or rely on backdoor triggers, AdvSR operates entirely at the model level. By jointly optimizing for reconstruction quality and targeted adversarial outcomes, AdvSR produces models that appear benign under standard image quality metrics while inducing downstream misclassification. We evaluate AdvSR on three SR architectures (SRCNN, EDSR, SwinIR) paired with a YOLOv11 classifier and demonstrate that AdvSR models can achieve high attack success rates with minimal quality degradation. These findings highlight a new model-level threat for imaging pipelines, with implications for how practitioners source and validate models in safety-critical applications.
[237] 3D Transport-based Morphometry (3D-TBM) for medical image analysis
Hongyu Kan, Kristofor Pas, Ivan Medri, Naqib Sad Pathan, Natasha Ironside, Shinjini Kundu, Jingjia He, Gustavo Kunde Rohde
Main category: cs.CV
TL;DR: 3D-TBM is a tool for morphological analysis of 3D medical images using transport-based morphometry, enabling classification, regression, and interpretable spatial analysis through invertible transport transformations.
Details
Motivation: To facilitate broader adoption of Transport-Based Morphometry (TBM) in clinical imaging research by providing an accessible tool for 3D medical image analysis that enables interpretable spatial analysis through invertible transformations.Method: Developed 3D-TBM framework with data preprocessing, computation of optimal transport embeddings, and analytical methods including visualization of main transport directions and techniques for discerning discriminating directions. The tool uses invertible transformations to embed images into a transport domain for analysis.
Result: Created a comprehensive tool for 3D medical image analysis with publicly available source code through PyTransKit, including documentation and practical tutorials to support researchers in applying TBM to their medical imaging studies.
Conclusion: 3D-TBM provides an accessible framework for transport-based morphometry in 3D medical imaging, enabling effective analysis with interpretable spatial results that can be projected back to the original image space for clinical interpretation.
Abstract: Transport-Based Morphometry (TBM) has emerged as a new framework for 3D medical image analysis. By embedding images into a transport domain via invertible transformations, TBM facilitates effective classification, regression, and other tasks using transport-domain features. Crucially, the inverse mapping enables the projection of analytic results back into the original image space, allowing researchers to directly interpret clinical features associated with model outputs in a spatially meaningful way. To facilitate broader adoption of TBM in clinical imaging research, we present 3D-TBM, a tool designed for morphological analysis of 3D medical images. The framework includes data preprocessing, computation of optimal transport embeddings, and analytical methods such as visualization of main transport directions, together with techniques for discerning discriminating directions and related analysis methods. We also provide comprehensive documentation and practical tutorials to support researchers interested in applying 3D-TBM in their own medical imaging studies. The source code is publicly available through PyTransKit.
[238] TwistNet-2D: Learning Second-Order Channel Interactions via Spiral Twisting for Texture Recognition
Junbo Jacob Lian, Feng Xiong, Yujun Sun, Kaichen Ouyang, Mingyang Yu, Shengwei Fu, Zhong Rui, Zhang Yujun, Huiling Chen
Main category: cs.CV
TL;DR: TwistNet-2D is a lightweight module that captures local pairwise channel interactions with directional spatial displacement for texture recognition, outperforming larger models with minimal computational overhead.
Details
Motivation: Current methods for texture recognition face limitations: bilinear pooling and Gram matrices capture global channel correlations but lose spatial structure, while self-attention models spatial context through weighted aggregation rather than explicit pairwise feature interactions. There's a need for a method that jointly encodes where features co-occur and how they interact spatially.Method: Introduces TwistNet-2D with Spiral-Twisted Channel Interaction (STCI) that shifts one feature map along prescribed directions before element-wise channel multiplication. This captures cross-position co-occurrence patterns. Uses four directional heads with learned channel reweighting and injects results through a sigmoid-gated residual path.
Result: TwistNet-2D adds only 3.5% additional parameters and 2% additional FLOPs over ResNet-18, yet consistently surpasses both parameter-matched and substantially larger baselines (ConvNeXt, Swin Transformer, hybrid CNN-Transformer architectures) across four texture and fine-grained recognition benchmarks.
Conclusion: The proposed method effectively captures local pairwise channel interactions with directional spatial displacement, providing an efficient and effective solution for texture and fine-grained recognition tasks.
Abstract: Second-order feature statistics are central to texture recognition, yet current methods face a fundamental tension: bilinear pooling and Gram matrices capture global channel correlations but collapse spatial structure, while self-attention models spatial context through weighted aggregation rather than explicit pairwise feature interactions. We introduce TwistNet-2D, a lightweight module that computes \emph{local} pairwise channel products under directional spatial displacement, jointly encoding where features co-occur and how they interact. The core component, Spiral-Twisted Channel Interaction (STCI), shifts one feature map along a prescribed direction before element-wise channel multiplication, thereby capturing the cross-position co-occurrence patterns characteristic of structured and periodic textures. Aggregating four directional heads with learned channel reweighting and injecting the result through a sigmoid-gated residual path, \TwistNet incurs only 3.5% additional parameters and 2% additional FLOPs over ResNet-18, yet consistently surpasses both parameter-matched and substantially larger baselines – including ConvNeXt, Swin Transformer, and hybrid CNN–Transformer architectures – across four texture and fine-grained recognition benchmarks.
[239] VideoNeuMat: Neural Material Extraction from Generative Video Models
Bowen Xue, Saeed Hadadan, Zheng Zeng, Fabrice Rousselle, Zahra Montazeri, Milos Hasan
Main category: cs.CV
TL;DR: VideoNeuMat extracts reusable neural material assets from video diffusion models by generating controlled material sample videos and reconstructing compact neural materials that generalize to novel viewing/lighting conditions.
Details
Motivation: Creating photorealistic materials for 3D rendering requires exceptional artistic skill, and generative models for materials are limited by lack of high-quality training data. While video generative models can produce realistic material appearances, this knowledge remains entangled with geometry and lighting.Method: Two-stage pipeline: 1) Finetune large video model (Wan 2.1 14B) to generate material sample videos under controlled camera/lighting trajectories (virtual gonioreflectometer), 2) Reconstruct compact neural materials from videos using Large Reconstruction Model (LRM) finetuned from smaller Wan 1.3B video backbone, performing single-pass inference from 17 frames.
Result: The resulting materials exhibit realism and diversity far exceeding limited synthetic training data, demonstrating successful transfer of material knowledge from internet-scale video models into standalone, reusable neural 3D assets.
Conclusion: Material knowledge can be successfully transferred from internet-scale video models into reusable neural 3D assets, enabling creation of photorealistic materials without requiring extensive artistic skill or large training datasets.
Abstract: Creating photorealistic materials for 3D rendering requires exceptional artistic skill. Generative models for materials could help, but are currently limited by the lack of high-quality training data. While recent video generative models effortlessly produce realistic material appearances, this knowledge remains entangled with geometry and lighting. We present VideoNeuMat, a two-stage pipeline that extracts reusable neural material assets from video diffusion models. First, we finetune a large video model (Wan 2.1 14B) to generate material sample videos under controlled camera and lighting trajectories, effectively creating a “virtual gonioreflectometer” that preserves the model’s material realism while learning a structured measurement pattern. Second, we reconstruct compact neural materials from these videos through a Large Reconstruction Model (LRM) finetuned from a smaller Wan 1.3B video backbone. From 17 generated video frames, our LRM performs single-pass inference to predict neural material parameters that generalize to novel viewing and lighting conditions. The resulting materials exhibit realism and diversity far exceeding the limited synthetic training data, demonstrating that material knowledge can be successfully transferred from internet-scale video models into standalone, reusable neural 3D assets.
[240] Cross-View World Models
Rishabh Sharma, Gijs Hogervorst, Wayne E. Mackey, David J. Heeger, Stefano Martiniani
Main category: cs.CV
TL;DR: Cross-View World Models (XVWM) learn to predict future states from different viewpoints using cross-view prediction as geometric regularization, enabling planning from optimal perspectives while executing egocentrically.
Details
Motivation: Existing world models operate from single viewpoints (typically egocentric), but planning could be easier from other perspectives (e.g., navigation benefits from bird's-eye view). The paper aims to create models that can imagine future states from different viewpoints.Method: XVWM uses cross-view prediction objective: given frames from one viewpoint, predict future state from same or different viewpoint after an action. Trained on synchronized multi-view gameplay data from Aimlabs with precisely aligned multi-camera recordings and high-frequency action labels.
Result: The model learns view-invariant representations of 3D structure through cross-view consistency, provides agents with parallel imagination streams across viewpoints, and enables planning in optimal reference frames while executing from egocentric view.
Conclusion: Multi-view consistency provides strong learning signal for spatially grounded representations, and predicting consequences from other viewpoints may offer foundation for perspective-taking in multi-agent settings.
Abstract: World models enable agents to plan by imagining future states, but existing approaches operate from a single viewpoint, typically egocentric, even when other perspectives would make planning easier; navigation, for instance, benefits from a bird’s-eye view. We introduce Cross-View World Models (XVWM), trained with a cross-view prediction objective: given a sequence of frames from one viewpoint, predict the future state from the same or a different viewpoint after an action is taken. Enforcing cross-view consistency acts as geometric regularization: because the input and output views may share little or no visual overlap, to predict across viewpoints, the model must learn view-invariant representations of the environment’s 3D structure. We train on synchronized multi-view gameplay data from Aimlabs, an aim-training platform providing precisely aligned multi-camera recordings with high-frequency action labels. The resulting model gives agents parallel imagination streams across viewpoints, enabling planning in whichever frame of reference best suits the task while executing from the egocentric view. Our results show that multi-view consistency provides a strong learning signal for spatially grounded representations. Finally, predicting the consequences of one’s actions from another viewpoint may offer a foundation for perspective-taking in multi-agent settings.
[241] Diabetic Retinopathy Lesion Segmentation through Attention Mechanisms
Aruna Jithesh, Chinmayi Karumuri, Venkata Kiran Reddy Kotha, Meghana Doddapuneni, Taehee Jeong
Main category: cs.CV
TL;DR: Attention-enhanced DeepLab-V3+ for diabetic retinopathy lesion segmentation in fundus images, improving detection of microaneurysms and other DR-related lesions.
Details
Motivation: Early detection of Diabetic Retinopathy (DR) is crucial to prevent vision loss, but existing deep learning methods have limited clinical applicability for lesion segmentation. The paper aims to provide pixel-level lesion annotations to support ophthalmologists in DR screening.Method: Used Attention mechanism integrated with DeepLab-V3+ architecture for segmenting four DR lesion types (microaneurysms, soft exudates, hard exudates, hemorrhages) on 757 images from DDR dataset.
Result: Attention-DeepLab increased mAP from 0.3010 to 0.3326 and mean IoU from 0.1791 to 0.1928. Most notably improved microaneurysm detection from 0.0205 to 0.0763, which is clinically significant as microaneurysms are the earliest visible DR symptom.
Conclusion: The attention-enhanced model provides better lesion segmentation for DR screening, with particular improvement in detecting early-stage microaneurysms, supporting clinical applications.
Abstract: Diabetic Retinopathy (DR) is an eye disease which arises due to diabetes mellitus. It might cause vision loss and blindness. To prevent irreversible vision loss, early detection through systematic screening is crucial. Although researchers have developed numerous automated deep learning-based algorithms for DR screening, their clinical applicability remains limited, particularly in lesion segmentation. Our method provides pixel-level annotations for lesions, which practically supports Ophthalmologist to screen DR from fundus images. In this work, we segmented four types of DR-related lesions: microaneurysms, soft exudates, hard exudates, and hemorrhages on 757 images from DDR dataset. To enhance lesion segmentation, an attention mechanism was integrated with DeepLab-V3+. Compared to the baseline model, the Attention-DeepLab model increases mean average precision (mAP) from 0.3010 to 0.3326 and the mean Intersection over Union (IoU) from 0.1791 to 0.1928. The model also increased microaneurysm detection from 0.0205 to 0.0763, a clinically significant improvement. The detection of microaneurysms is the earliest visible symptom of DR.
[242] Optimization of Precipitate Segmentation Through Linear Genetic Programming of Image Processing
Kyle Williams, Andrew Seltzman
Main category: cs.CV
TL;DR: Automated image segmentation algorithm using linear genetic programming to detect precipitates in micrographs of additive manufactured copper alloys, enabling faster material development.
Details
Motivation: Current manual annotation of micrographs for analyzing additive manufactured niobium-based copper alloys is slow and hinders rapid iteration in alloy development due to varying contrast, noise, and image artifacts.Method: Developed a filtering and segmentation algorithm optimized using linear genetic programming (LGP) with a domain-specific language for image processing. The system generates human-interpretable MATLAB code representing image filtering pipelines with tunable parameters.
Result: Achieved near-human accuracy with 1.8% average evaluation error compared to human baseline, processing 3.6 megapixel images in about 2 seconds, enabling faster iteration cycles in material development.
Conclusion: The automated pipeline accelerates exploration of material composition and processing space, facilitating development of strong, low-activation precipitation hardened copper alloys for additive manufactured fusion reactor parts.
Abstract: Current analysis of additive manufactured niobium-based copper alloys relies on hand annotation due to varying contrast, noise, and image artifacts present in micrographs, slowing iteration speed in alloy development. We present a filtering and segmentation algorithm for detecting precipitates in FIB cross-section micrographs, optimized using linear genetic programming (LGP), which accounts for the various artifacts. To this end, the optimization environment uses a domain-specific language for image processing to iterate on solutions. Programs in this language are a list of image-filtering blocks with tunable parameters that sequentially process an input image, allowing for reliable generation and mutation by a genetic algorithm. Our environment produces optimized human-interpretable MATLAB code representing an image filtering pipeline. Under ideal conditions–a population size of 60 and a maximum program length of 5 blocks–our system was able to find a near-human accuracy solution with an average evaluation error of 1.8% when comparing segmentations pixel-by-pixel to a human baseline using an XOR error evaluation. Our automation work enabled faster iteration cycles and furthered exploration of the material composition and processing space: our optimized pipeline algorithm processes a 3.6 megapixel image in about 2 seconds on average. This ultimately enables convergence on strong, low-activation, precipitation hardened copper alloys for additive manufactured fusion reactor parts.
[243] LUCID-SAE: Learning Unified Vision-Language Sparse Codes for Interpretable Concept Discovery
Difei Gu, Yunhe Gao, Gerasimos Chatzoudis, Zihan Dong, Guoning Zhang, Bangwei Guo, Yang Zhou, Mu Zhou, Dimitris Metaxas
Main category: cs.CV
TL;DR: LUCID is a unified vision-language sparse autoencoder that learns shared latent dictionaries for image patches and text tokens, enabling interpretable cross-modal concept discovery without manual labeling.
Details
Motivation: Current sparse autoencoders are trained per modality, producing features that aren't directly understandable and don't transfer across domains. There's a need for unified representations that can discover interpretable concepts shared between vision and language modalities.Method: LUCID learns a shared latent dictionary for image patch and text token representations while reserving private capacity for modality-specific details. It achieves feature alignment through optimal transport matching without labeling, and includes automated dictionary interpretation via term clustering.
Result: LUCID produces interpretable shared features that support patch-level grounding, establish cross-modal neuron correspondence, enhance robustness against concept clustering problems, and capture diverse semantic categories including objects, actions, attributes, and abstract concepts.
Conclusion: LUCID demonstrates a comprehensive approach to interpretable multimodal representations, enabling automated concept discovery and cross-modal alignment without manual intervention, advancing the field of multimodal interpretability.
Abstract: Sparse autoencoders (SAEs) offer a natural path toward comparable explanations across different representation spaces. However, current SAEs are trained per modality, producing dictionaries whose features are not directly understandable and whose explanations do not transfer across domains. In this study, we introduce LUCID (Learning Unified vision-language sparse Codes for Interpretable concept Discovery), a unified vision-language sparse autoencoder that learns a shared latent dictionary for image patch and text token representations, while reserving private capacity for modality-specific details. We achieve feature alignment by coupling the shared codes with a learned optimal transport matching objective without the need of labeling. LUCID yields interpretable shared features that support patch-level grounding, establish cross-modal neuron correspondence, and enhance robustness against the concept clustering problem in similarity-based evaluation. Leveraging the alignment properties, we develop an automated dictionary interpretation pipeline based on term clustering without manual observations. Our analysis reveals that LUCID’s shared features capture diverse semantic categories beyond objects, including actions, attributes, and abstract concepts, demonstrating a comprehensive approach to interpretable multimodal representations.
[244] Seeing Roads Through Words: A Language-Guided Framework for RGB-T Driving Scene Segmentation
Ruturaj Reddy, Hrishav Bakul Barua, Junn Yong Loo, Thanh Thi Nguyen, Ganesh Krishnasamy
Main category: cs.CV
TL;DR: CLARITY: Dynamic RGB-Thermal fusion for robust semantic segmentation in adverse lighting conditions using VLM priors to adapt fusion strategy based on scene illumination.
Details
Motivation: Existing RGB-Thermal fusion methods use static strategies that propagate modality-specific noise across all conditions, failing to adapt to varying illumination, lighting, and shadow conditions in autonomous driving scenarios.Method: Proposes CLARITY that dynamically adapts fusion strategy using vision-language model (VLM) priors to modulate each modality’s contribution based on detected scene conditions. Includes mechanisms to preserve valid dark-object semantics and a hierarchical decoder for structural consistency across scales.
Result: Achieves new state-of-the-art on MFNet dataset with 62.3% mIoU and 77.5% mAcc, demonstrating superior performance in adverse lighting conditions.
Conclusion: Dynamic fusion guided by VLM priors outperforms static fusion strategies for RGB-Thermal semantic segmentation in challenging illumination conditions, with applications for autonomous driving.
Abstract: Robust semantic segmentation of road scenes under adverse illumination, lighting, and shadow conditions remain a core challenge for autonomous driving applications. RGB-Thermal fusion is a standard approach, yet existing methods apply static fusion strategies uniformly across all conditions, allowing modality-specific noise to propagate throughout the network. Hence, we propose CLARITY that dynamically adapts its fusion strategy to the detected scene condition. Guided by vision-language model (VLM) priors, the network learns to modulate each modality’s contribution based on the illumination state while leveraging object embeddings for segmentation, rather than applying a fixed fusion policy. We further introduce two mechanisms, i.e., one which preserves valid dark-object semantics that prior noise-suppression methods incorrectly discard, and a hierarchical decoder that enforces structural consistency across scales to sharpen boundaries on thin objects. Experiments on the MFNet dataset demonstrate that CLARITY establishes a new state-of-the-art (SOTA), achieving 62.3% mIoU and 77.5% mAcc.
[245] Optimizing Few-Step Generation with Adaptive Matching Distillation
Lichen Bai, Zikai Zhou, Shitong Shao, Wenliang Zhong, Shuo Yang, Shuo Chen, Bojun Chen, Zeke Xie
Main category: cs.CV
TL;DR: AMD introduces a self-correcting distillation framework that detects and escapes “Forbidden Zones” where teacher models provide unreliable guidance, improving stability and performance in few-step generative models.
Details
Motivation: Current Distribution Matching Distillation (DMD) methods suffer from instability in "Forbidden Zones" - regions where real teacher models provide unreliable guidance while fake teachers exert insufficient repulsive force, leading to degraded performance in few-step generative models.Method: Proposes Adaptive Matching Distillation (AMD) with: 1) Reward proxies to explicitly detect Forbidden Zones, 2) Structural signal decomposition to prioritize corrective gradients, and 3) Repulsive Landscape Sharpening to enforce steep energy barriers against failure mode collapse.
Result: AMD significantly enhances sample fidelity and training robustness across image and video generation tasks (SDXL, Wan2.1). Improves HPSv2 score on SDXL from 30.64 to 31.25, outperforming state-of-the-art baselines on benchmarks like VBench and GenEval.
Conclusion: Explicitly rectifying optimization trajectories within Forbidden Zones is essential for pushing the performance ceiling of few-step generative models, and AMD provides an effective self-correcting mechanism for stable distillation.
Abstract: Distribution Matching Distillation (DMD) is a powerful acceleration paradigm, yet its stability is often compromised in Forbidden Zone, regions where the real teacher provides unreliable guidance while the fake teacher exerts insufficient repulsive force. In this work, we propose a unified optimization framework that reinterprets prior art as implicit strategies to avoid these corrupted regions. Based on this insight, we introduce Adaptive Matching Distillation (AMD), a self-correcting mechanism that utilizes reward proxies to explicitly detect and escape Forbidden Zones. AMD dynamically prioritizes corrective gradients via structural signal decomposition and introduces Repulsive Landscape Sharpening to enforce steep energy barriers against failure mode collapse. Extensive experiments across image and video generation tasks (e.g., SDXL, Wan2.1) and rigorous benchmarks (e.g., VBench, GenEval) demonstrate that AMD significantly enhances sample fidelity and training robustness. For instance, AMD improves the HPSv2 score on SDXL from 30.64 to 31.25, outperforming state-of-the-art baselines. These findings validate that explicitly rectifying optimization trajectories within Forbidden Zones is essential for pushing the performance ceiling of few-step generative models.
[246] Row-Column Separated Attention Based Low-Light Image/Video Enhancement
Chengqi Dong, Zhiyuan Cao, Tuoshi Qi, Kexin Wu, Yixing Gao, Fan Tang
Main category: cs.CV
TL;DR: Proposes URCSA: U-Net with Row-Column Separated Attention for low-light image/video enhancement, using global information guidance with fewer parameters and temporal consistency losses for videos.
Details
Motivation: U-Net structures for low-light enhancement lack proper global information guidance, leading to local noise and detail loss. Attention mechanisms help but increase parameters/computations significantly.Method: Improved U-Net with Row-Column Separated Attention (RCSA) module that takes row/column means and maxes of feature maps to guide local information with fewer parameters. Two temporal loss functions for video consistency.
Result: Extensive experiments on LOL, MIT Adobe FiveK image datasets and SDSD video dataset demonstrate effectiveness of the approach.
Conclusion: URCSA effectively enhances low-light images/videos with better global guidance and temporal consistency while maintaining computational efficiency.
Abstract: U-Net structure is widely used for low-light image/video enhancement. The enhanced images result in areas with large local noise and loss of more details without proper guidance for global information. Attention mechanisms can better focus on and use global information. However, attention to images could significantly increase the number of parameters and computations. We propose a Row-Column Separated Attention module (RCSA) inserted after an improved U-Net. The RCSA module’s input is the mean and maximum of the row and column of the feature map, which utilizes global information to guide local information with fewer parameters. We propose two temporal loss functions to apply the method to low-light video enhancement and maintain temporal consistency. Extensive experiments on the LOL, MIT Adobe FiveK image, and SDSD video datasets demonstrate the effectiveness of our approach. The code is publicly available at https://github.com/cq-dong/URCSA.
[247] Perspective-aware fusion of incomplete depth maps and surface normals for accurate 3D reconstruction
Ondrej Hlinka, Georg Kaniak, Christian Kapeller
Main category: cs.CV
TL;DR: A method for 3D surface reconstruction from depth and normal maps using perspective-aware log-depth fusion that handles missing measurements.
Details
Motivation: Existing gradient-based depth-normals fusion methods assume orthographic projection, which limits metric accuracy in perspective camera systems. There's a need for methods that explicitly account for perspective projection for accurate 3D reconstructions.Method: Proposes a perspective-aware log-depth fusion approach that extends orthographic gradient-based methods by explicitly modeling perspective projection. Uses log-depth representation and handles missing depth measurements by leveraging surface normal information for inpainting.
Result: Experiments on DiLiGenT-MV dataset demonstrate effectiveness and show importance of perspective-aware depth-normals fusion for metrically accurate 3D reconstructions.
Conclusion: The perspective-aware approach significantly improves 3D reconstruction accuracy over orthographic methods, especially for perspective camera systems, and effectively handles missing depth data through normal-based inpainting.
Abstract: We address the problem of reconstructing 3D surfaces from depth and surface normal maps acquired by a sensor system based on a single perspective camera. Depth and normal maps can be obtained through techniques such as structured-light scanning and photometric stereo, respectively. We propose a perspective-aware log-depth fusion approach that extends existing orthographic gradient-based depth-normals fusion methods by explicitly accounting for perspective projection, leading to metrically accurate 3D reconstructions. Additionally, the method handles missing depth measurements by leveraging available surface normal information to inpaint gaps. Experiments on the DiLiGenT-MV data set demonstrate the effectiveness of our approach and highlight the importance of perspective-aware depth-normals fusion.
[248] PTB-XL-Image-17K: A Large-Scale Synthetic ECG Image Dataset with Comprehensive Ground Truth for Deep Learning-Based Digitization
Naqcho Ali Mehdi
Main category: cs.CV
TL;DR: PTB-XL-Image-17K is a synthetic ECG image dataset with 17,271 12-lead ECG images generated from PTB-XL signals, providing comprehensive annotations for ECG digitization research.
Details
Motivation: ECG digitization from paper/scanned images is crucial for using legacy clinical data in deep learning, but progress has been hindered by lack of large-scale datasets with both images and ground truth signals.Method: Created a synthetic ECG image dataset from PTB-XL signal database using an open-source Python framework with customizable parameters (paper speed, voltage scale, sampling rate, grid appearance, waveform characteristics).
Result: Dataset contains 17,271 high-quality ECG images with five complementary data types per sample: realistic images, segmentation masks, time-series signals, bounding boxes, and comprehensive metadata. Achieved 100% generation success rate with 1.35 seconds per sample.
Conclusion: PTB-XL-Image-17K addresses critical gaps in ECG digitization research by providing the first large-scale resource supporting the complete pipeline from lead detection to signal extraction with full ground truth for evaluation.
Abstract: Electrocardiogram (ECG) digitization-converting paper-based or scanned ECG images back into time-series signals-is critical for leveraging decades of legacy clinical data in modern deep learning applications. However, progress has been hindered by the lack of large-scale datasets providing both ECG images and their corresponding ground truth signals with comprehensive annotations. We introduce PTB-XL-Image-17K, a complete synthetic ECG image dataset comprising 17,271 high-quality 12-lead ECG images generated from the PTB-XL signal database. Our dataset uniquely provides five complementary data types per sample: (1) realistic ECG images with authentic grid patterns and annotations (50% with visible grid, 50% without), (2) pixel-level segmentation masks, (3) ground truth time-series signals, (4) bounding box annotations in YOLO format for both lead regions and lead name labels, and (5) comprehensive metadata including visual parameters and patient information. We present an open-source Python framework enabling customizable dataset generation with controllable parameters including paper speed (25/50 mm/s), voltage scale (5/10 mm/mV), sampling rate (500 Hz), grid appearance (4 colors), and waveform characteristics. The dataset achieves 100% generation success rate with an average processing time of 1.35 seconds per sample. PTB-XL-Image-17K addresses critical gaps in ECG digitization research by providing the first large-scale resource supporting the complete pipeline: lead detection, waveform segmentation, and signal extraction with full ground truth for rigorous evaluation. The dataset, generation framework, and documentation are publicly available at https://github.com/naqchoalimehdi/PTB-XL-Image-17K and https://doi.org/10.5281/zenodo.18197519.
[249] SoulX-FlashHead: Oracle-guided Generation of Infinite Real-time Streaming Talking Heads
Tan Yu, Qian Qiao, Le Shen, Ke Zhou, Jincheng Hu, Dian Sheng, Bo Hu, Haoming Qin, Jun Gao, Changhai Zhou, Shunshun Yin, Siyuan Liu
Main category: cs.CV
TL;DR: SoulX-FlashHead: A 1.3B-parameter framework for real-time, high-fidelity audio-driven portrait video generation with streaming capabilities
Details
Motivation: Address the challenge of balancing high-fidelity visual quality with low-latency streaming in audio-driven portrait generation, overcoming limitations of existing models that are either computationally expensive or compromise on facial representation and temporal stabilityMethod: Proposes a unified 1.3B-parameter framework with Streaming-Aware Spatiotemporal Pre-training using Temporal Audio Context Cache for robust feature extraction from short audio fragments, and Oracle-Guided Bidirectional Distillation to mitigate error accumulation in long-sequence autoregressive generation
Result: Achieves state-of-the-art performance on HDTF and VFHQ benchmarks, with Lite variant reaching 96 FPS on single NVIDIA RTX 4090, enabling ultra-fast interaction without sacrificing visual coherence
Conclusion: SoulX-FlashHead successfully addresses the trade-off between quality and latency in audio-driven portrait generation, providing a practical solution for real-time streaming applications with high visual fidelity
Abstract: Achieving a balance between high-fidelity visual quality and low-latency streaming remains a formidable challenge in audio-driven portrait generation. Existing large-scale models often suffer from prohibitive computational costs, while lightweight alternatives typically compromise on holistic facial representations and temporal stability. In this paper, we propose SoulX-FlashHead, a unified 1.3B-parameter framework designed for real-time, infinite-length, and high-fidelity streaming video generation. To address the instability of audio features in streaming scenarios, we introduce Streaming-Aware Spatiotemporal Pre-training equipped with a Temporal Audio Context Cache mechanism, which ensures robust feature extraction from short audio fragments. Furthermore, to mitigate the error accumulation and identity drift inherent in long-sequence autoregressive generation, we propose Oracle-Guided Bidirectional Distillation, leveraging ground-truth motion priors to provide precise physical guidance. We also present VividHead, a large-scale, high-quality dataset containing 782 hours of strictly aligned footage to support robust training. Extensive experiments demonstrate that SoulX-FlashHead achieves state-of-the-art performance on HDTF and VFHQ benchmarks. Notably, our Lite variant achieves an inference speed of 96 FPS on a single NVIDIA RTX 4090, facilitating ultra-fast interaction without sacrificing visual coherence.
[250] SpatialReward: Bridging the Perception Gap in Online RL for Image Editing via Explicit Spatial Reasoning
Yancheng Long, Yankai Yang, Hongyang Wei, Wei Chen, Tianke Zhang, Haonan fan, Changyi Liu, Kaiyu Jiang, Jiankang Chen, Kaiyu Tang, Bin Wen, Fan Yang, Tingting Gao, Han Li, Shuo Yang
Main category: cs.CV
TL;DR: SpatialReward is a spatial reasoning-based reward model for online RL in image editing that addresses attention collapse by anchoring semantic judgments to pixel-level evidence, achieving SOTA performance on multiple benchmarks.
Details
Motivation: Online RL for image editing lacks reliable fine-grained reward signals due to "Attention Collapse" - existing evaluators neglect cross-image comparisons and fine details, leading to inaccurate perception and miscalibrated scores.Method: Proposes SpatialReward, a reward model that enforces precise verification via explicit spatial reasoning by anchoring reasoning to predicted edit regions, grounding semantic judgments in pixel-level evidence. Trained on a curated 260k spatial-aware dataset.
Result: Achieves SOTA performance on MMRB2 and EditReward-Bench, outperforms proprietary evaluators on MultiEditReward-Bench. Boosts OmniGen2 by +0.90 on GEdit-Bench, surpassing leading discriminative model and doubling GPT-4.1’s gain (+0.45).
Conclusion: Spatial reasoning is essential for unlocking effective alignment in image editing, and SpatialReward demonstrates superior performance as a robust reward signal for online RL in image editing tasks.
Abstract: Online Reinforcement Learning (RL) offers a promising avenue for complex image editing but is currently constrained by the scarcity of reliable and fine-grained reward signals. Existing evaluators frequently struggle with a critical perception gap we term “Attention Collapse,” where models neglect cross-image comparisons and fail to capture fine-grained details, resulting in inaccurate perception and miscalibrated scores. To address these limitations, we propose SpatialReward, a reward model that enforces precise verification via explicit spatial reasoning. By anchoring reasoning to predicted edit regions, SpatialReward grounds semantic judgments in pixel-level evidence, significantly enhancing evaluative accuracy. Trained on a curated 260k spatial-aware dataset, our model achieves state-of-the-art performance on MMRB2 and EditReward-Bench, and outperforms proprietary evaluators on our proposed MultiEditReward-Bench. Furthermore, SpatialReward serves as a robust signal in online RL, boosting OmniGen2 by +0.90 on GEdit-Bench–surpassing the leading discriminative model and doubling the gain of GPT-4.1 (+0.45). These results demonstrate that spatial reasoning is essential for unlocking effective alignment in image editing.
[251] GlobalWasteData: A Large-Scale, Integrated Dataset for Robust Waste Classification and Environmental Monitoring
Misbah Ijaz, Saif Ur Rehman Khan, Abd Ur Rehman, Tayyaba Asif, Sebastian Vollmer, Andreas Dengel, Muhammad Nabeel Asim
Main category: cs.CV
TL;DR: The paper introduces GlobalWasteData (GWD), a large-scale integrated dataset of 89,807 waste images across 14 main categories and 68 subclasses, created by merging multiple fragmented public datasets to enable robust waste classification models.
Details
Motivation: Existing waste classification datasets are fragmented, inconsistent, and biased toward specific environments, making it difficult to combine datasets or train models that generalize well to real-world scenarios due to differences in class names, annotation formats, image conditions, and class distributions.Method: Created the GlobalWasteData (GWD) archive by merging multiple publicly available waste classification datasets into a single unified resource, with additional preprocessing steps including quality filtering, duplicate removal, and metadata generation to improve dataset reliability.
Result: The resulting GWD archive contains 89,807 images across 14 main categories annotated with 68 distinct subclasses, offering consistent labeling, improved domain diversity, and more balanced class representation compared to existing fragmented datasets.
Conclusion: GWD provides a strong foundation for ML applications in environmental monitoring, recycling automation, and waste identification, and is publicly available to promote future research and reproducibility in waste classification.
Abstract: The growing amount of waste is a problem for the environment that requires efficient sorting techniques for various kinds of waste. An automated waste classification system is used for this purpose. The effectiveness of these Artificial Intelligence (AI) models depends on the quality and accessibility of publicly available datasets, which provide the basis for training and analyzing classification algorithms. Although several public waste classification datasets exist, they remain fragmented, inconsistent, and biased toward specific environments. Differences in class names, annotation formats, image conditions, and class distributions make it difficult to combine these datasets or train models that generalize well to real world scenarios. To address these issues, we introduce the GlobalWasteData (GWD) archive, a large scale dataset of 89,807 images across 14 main categories, annotated with 68 distinct subclasses. We compile this novel integrated GWD archive by merging multiple publicly available datasets into a single, unified resource. This GWD archive offers consistent labeling, improved domain diversity, and more balanced class representation, enabling the development of robust and generalizable waste recognition models. Additional preprocessing steps such as quality filtering, duplicate removal, and metadata generation further improve dataset reliability. Overall, this dataset offers a strong foundation for Machine Learning (ML) applications in environmental monitoring, recycling automation, and waste identification, and is publicly available to promote future research and reproducibility.
[252] Thermal odometry and dense mapping using learned ddometry and Gaussian splatting
Tianhao Zhou, Yujia Chen, Zhihao Zhan, Yuhang Ming, Jianzhu Huai
Main category: cs.CV
TL;DR: TOM-GS: A thermal odometry and mapping method combining learning-based odometry with Gaussian Splatting for dense reconstruction from thermal cameras, featuring thermal image enhancement and monocular depth integration.
Details
Motivation: Thermal cameras are robust in adverse conditions (darkness, dust, smoke) but existing thermal odometry/mapping approaches are predominantly geometric, fail across diverse datasets, and lack dense mapping capabilities. Recent Gaussian Splatting techniques offer efficient high-quality reconstruction.Method: Proposes TOM-GS that integrates learning-based odometry with Gaussian Splatting-based dense mapping. Features dedicated thermal image enhancement and monocular depth integration. Among first GS-based SLAM systems tailored for thermal cameras.
Result: Extensive experiments on motion estimation and novel-view rendering demonstrate TOM-GS outperforms existing learning-based methods, confirming benefits of learning-based pipelines for robust thermal odometry and dense reconstruction.
Conclusion: TOM-GS successfully combines learning-based odometry with Gaussian Splatting for thermal cameras, achieving superior performance in motion estimation and dense reconstruction compared to existing methods.
Abstract: Thermal infrared sensors, with wavelengths longer than smoke particles, can capture imagery independent of darkness, dust, and smoke. This robustness has made them increasingly valuable for motion estimation and environmental perception in robotics, particularly in adverse conditions. Existing thermal odometry and mapping approaches, however, are predominantly geometric and often fail across diverse datasets while lacking the ability to produce dense maps. Motivated by the efficiency and high-quality reconstruction ability of recent Gaussian Splatting (GS) techniques, we propose TOM-GS, a thermal odometry and mapping method that integrates learning-based odometry with GS-based dense mapping. TOM-GS is among the first GS-based SLAM systems tailored for thermal cameras, featuring dedicated thermal image enhancement and monocular depth integration. Extensive experiments on motion estimation and novel-view rendering demonstrate that TOM-GS outperforms existing learning-based methods, confirming the benefits of learning-based pipelines for robust thermal odometry and dense reconstruction.
[253] IM-Animation: An Implicit Motion Representation for Identity-decoupled Character Animation
Zhufeng Xu, Xuan Gao, Feng-Lin Liu, Haoxian Zhang, Zhixue Fang, Yu-Kun Lai, Xiaoqiang Liu, Pengfei Wan, Lin Gao
Main category: cs.CV
TL;DR: IM-Animation: A video diffusion model for character animation using implicit 1D motion tokens and mask token-based retargeting to address identity leakage and motion-appearance entanglement.
Details
Motivation: Existing character animation methods face limitations: explicit methods (using skeleton/DWPose) struggle with spatial mismatches and varying body scales, while implicit methods suffer from identity leakage and entanglement between motion and appearance.Method: Proposes implicit motion representation compressing per-frame motion into compact 1D motion tokens, relaxing spatial constraints and preventing identity leakage. Includes temporally consistent mask token-based retargeting module with temporal training bottleneck to mitigate source motion interference and improve consistency. Uses three-stage training strategy for efficiency and fidelity.
Result: Extensive experiments demonstrate superior or competitive performance compared to state-of-the-art methods, showing effective generative capabilities for character animation.
Conclusion: The proposed implicit motion representation and IM-Animation framework effectively address limitations of both explicit and implicit methods, achieving high-quality character animation with improved identity preservation and motion consistency.
Abstract: Recent progress in video diffusion models has markedly advanced character animation, which synthesizes motioned videos by animating a static identity image according to a driving video. Explicit methods represent motion using skeleton, DWPose or other explicit structured signals, but struggle to handle spatial mismatches and varying body scales. %proportions. Implicit methods, on the other hand, capture high-level implicit motion semantics directly from the driving video, but suffer from identity leakage and entanglement between motion and appearance. To address the above challenges, we propose a novel implicit motion representation that compresses per-frame motion into compact 1D motion tokens. This design relaxes strict spatial constraints inherent in 2D representations and effectively prevents identity information leakage from the motion video. Furthermore, we design a temporally consistent mask token-based retargeting module that enforces a temporal training bottleneck, mitigating interference from the source images’ motion and improving retargeting consistency. Our methodology employs a three-stage training strategy to enhance the training efficiency and ensure high fidelity. Extensive experiments demonstrate that our implicit motion representation and the propose IM-Animation’s generative capabilities are achieve superior or competitive performance compared with state-of-the-art methods.
[254] Adaptive Image Zoom-in with Bounding Box Transformation for UAV Object Detection
Tao Wang, Chenyu Lin, Chenwei Tang, Jizhe Zhou, Deng Xiong, Jianan Li, Jian Zhao, Jiancheng Lv
Main category: cs.CV
TL;DR: ZoomDet: An adaptive zoom-in framework for UAV object detection that non-uniformly zooms in on small objects to improve detection accuracy with minimal latency overhead.
Details
Motivation: UAV-captured images contain small, sparse objects that hinder effective object detection. Standard detectors struggle with these tiny objects, requiring a method to adaptively focus on relevant regions.Method: Two-stage approach: 1) Lightweight offset prediction with box-based zooming objective for non-uniform zooming, 2) Corner-aligned bounding box transformation to warp ground-truth boxes to zoomed space for training and predicted boxes back to original space for inference.
Result: Achieves significant improvements on UAV datasets: >8.4 mAP absolute gain on SeaDronesSee with Faster R-CNN, only ~3ms additional latency. Architecture-independent and works with any detector.
Conclusion: ZoomDet effectively addresses small object detection in UAV images through adaptive zooming, offering substantial accuracy gains with minimal computational overhead.
Abstract: Detecting objects from UAV-captured images is challenging due to the small object size. In this work, a simple and efficient adaptive zoom-in framework is explored for object detection on UAV images. The main motivation is that the foreground objects are generally smaller and sparser than those in common scene images, which hinders the optimization of effective object detectors. We thus aim to zoom in adaptively on the objects to better capture object features for the detection task. To achieve the goal, two core designs are required: \textcolor{black}{i) How to conduct non-uniform zooming on each image efficiently? ii) How to enable object detection training and inference with the zoomed image space?} Correspondingly, a lightweight offset prediction scheme coupled with a novel box-based zooming objective is introduced to learn non-uniform zooming on the input image. Based on the learned zooming transformation, a corner-aligned bounding box transformation method is proposed. The method warps the ground-truth bounding boxes to the zoomed space to learn object detection, and warps the predicted bounding boxes back to the original space during inference. We conduct extensive experiments on three representative UAV object detection datasets, including VisDrone, UAVDT, and SeaDronesSee. The proposed ZoomDet is architecture-independent and can be applied to an arbitrary object detection architecture. Remarkably, on the SeaDronesSee dataset, ZoomDet offers more than 8.4 absolute gain of mAP with a Faster R-CNN model, with only about 3 ms additional latency. The code is available at https://github.com/twangnh/zoomdet_code.
[255] CA-YOLO: Cross Attention Empowered YOLO for Biomimetic Localization
Zhen Zhang, Qing Zhao, Xiuhe Li, Cheng Wang, Guoqiang Zhu, Yu Zhang, Yining Huo, Hongyi Yu, Yi Zhang
Main category: cs.CV
TL;DR: A bionic stabilized localization system using CA-YOLO with small target detection head and attention mechanism, plus pan-tilt tracking inspired by human VOR reflex, achieving improved accuracy on COCO and VisDrone datasets.
Details
Motivation: Existing target localization systems have limitations in accuracy and small target recognition. Need for more accurate and efficient systems that can handle small targets in complex environments.Method: Proposes CA-YOLO with bionic modules: small target detection head and Characteristic Fusion Attention Mechanism (CFAM) in YOLO backbone. Also develops bionic pan-tilt tracking control strategy inspired by human Vestibulo-Ocular Reflex (VOR) with central positioning, stability optimization, adaptive control, and intelligent recapture.
Result: CA-YOLO outperforms original model on COCO (3.94% improvement) and VisDrone (4.90% improvement) datasets. Time-sensitive target localization experiments validate system effectiveness and practicality.
Conclusion: The bionic stabilized localization system successfully enhances target localization accuracy and small target recognition capabilities through biologically-inspired computer vision and control mechanisms.
Abstract: In modern complex environments, achieving accurate and efficient target localization is essential in numerous fields. However, existing systems often face limitations in both accuracy and the ability to recognize small targets. In this study, we propose a bionic stabilized localization system based on CA-YOLO, designed to enhance both target localization accuracy and small target recognition capabilities. Acting as the “brain” of the system, the target detection algorithm emulates the visual focusing mechanism of animals by integrating bionic modules into the YOLO backbone network. These modules include the introduction of a small target detection head and the development of a Characteristic Fusion Attention Mechanism (CFAM). Furthermore, drawing inspiration from the human Vestibulo-Ocular Reflex (VOR), a bionic pan-tilt tracking control strategy is developed, which incorporates central positioning, stability optimization, adaptive control coefficient adjustment, and an intelligent recapture function. The experimental results show that CA-YOLO outperforms the original model on standard datasets (COCO and VisDrone), with average accuracy metrics improved by 3.94%and 4.90%, respectively.Further time-sensitive target localization experiments validate the effectiveness and practicality of this bionic stabilized localization system.
[256] Evaluating Object-Centric Models beyond Object Discovery
Krishnakant Singh, Simone Schaub-Meyer, Stefan Roth
Main category: cs.CV
TL;DR: OCL evaluation benchmark using VLMs for complex reasoning tasks with unified metrics for localization and representation usefulness
Details
Motivation: Current OCL models are evaluated mainly on object discovery and simple reasoning tasks, providing limited insights into representation usefulness and using disjoint metrics for localization vs. usefulness assessmentMethod: Uses instruction-tuned VLMs as evaluators for scalable benchmarking across diverse VQA datasets, introduces unified evaluation task/metric for joint assessment of localization and representation usefulness, includes multi-feature reconstruction baseline
Result: Proposes a new evaluation framework that enables comprehensive assessment of OCL models’ representation quality for complex reasoning tasks through VLM-based evaluation
Conclusion: Addresses limitations in existing OCL benchmarks by providing unified evaluation that jointly assesses localization and representation usefulness using VLMs as scalable evaluators
Abstract: Object-centric learning (OCL) aims to learn structured scene representations that support compositional generalization and robustness to out-of-distribution (OOD) data. However, OCL models are often not evaluated regarding these goals. Instead, most prior work focuses on evaluating OCL models solely through object discovery and simple reasoning tasks, such as probing the representation via image classification. We identify two limitations in existing benchmarks: (1) They provide limited insights on the representation usefulness of OCL models, and (2) localization and representation usefulness are assessed using disjoint metrics. To address (1), we use instruction-tuned VLMs as evaluators, enabling scalable benchmarking across diverse VQA datasets to measure how well VLMs leverage OCL representations for complex reasoning tasks. To address (2), we introduce a unified evaluation task and metric that jointly assess localization (where) and representation usefulness (what), thereby eliminating inconsistencies introduced by disjoint evaluation. Finally, we include a simple multi-feature reconstruction baseline as a reference point.
[257] Beyond Core and Penumbra: Bi-Temporal Image-Driven Stroke Evolution Analysis
Md Sazidur Rahman, Kjersti Engan, Kathinka Dæhli Kurz, Mahdieh Khanmohammadi
Main category: cs.CV
TL;DR: Bi-temporal analysis framework using statistical, radiomic, and deep learning features from admission CTP and follow-up DWI to characterize ischemic tissue evolution in stroke patients.
Details
Motivation: Single time-point segmentations fail to capture biological heterogeneity and temporal evolution of stroke. Need to understand tissue state transitions from admission to outcome.Method: Extracted statistical descriptors, radiomic texture features, and deep feature embeddings (mJ-Net and nnU-Net) from admission CTP. Constructed six ROIs from intersected T1 and T2 masks. Analyzed feature space clustering of region-level representations.
Result: Meaningful clustering of region-level representations in 18 patients. Penumbra regions showed significant feature differences based on final outcome, while core regions did not. Deep feature spaces (especially mJ-Net) showed strong separation between salvageable and non-salvageable tissue.
Conclusion: Encoder-derived feature manifolds reflect underlying tissue phenotypes and state transitions, providing insight into imaging-based quantification of stroke evolution.
Abstract: Computed tomography perfusion (CTP) at admission is routinely used to estimate the ischemic core and penumbra, while follow-up diffusion-weighted MRI (DWI) provides the definitive infarct outcome. However, single time-point segmentations fail to capture the biological heterogeneity and temporal evolution of stroke. We propose a bi-temporal analysis framework that characterizes ischemic tissue using statistical descriptors, radiomic texture features, and deep feature embeddings from two architectures (mJ-Net and nnU-Net). Bi-temporal refers to admission (T1) and post-treatment follow-up (T2). All features are extracted at T1 from CTP, with follow-up DWI aligned to ensure spatial correspondence. Manually delineated masks at T1 and T2 are intersected to construct six regions of interest (ROIs) encoding both initial tissue state and final outcome. Features were aggregated per region and analyzed in feature space. Evaluation on 18 patients with successful reperfusion demonstrated meaningful clustering of region-level representations. Regions classified as penumbra or healthy at T1 that ultimately recovered exhibited feature similarity to preserved brain tissue, whereas infarct-bound regions formed distinct groupings. Both baseline GLCM and deep embeddings showed a similar trend: penumbra regions exhibit features that are significantly different depending on final state, whereas this difference is not significant for core regions. Deep feature spaces, particularly mJ-Net, showed strong separation between salvageable and non-salvageable tissue, with a penumbra separation index that differed significantly from zero (Wilcoxon signed-rank test). These findings suggest that encoder-derived feature manifolds reflect underlying tissue phenotypes and state transitions, providing insight into imaging-based quantification of stroke evolution.
[258] LLM-Guided Diagnostic Evidence Alignment for Medical Vision-Language Pretraining under Limited Pairing
Huimin Yan, Liang Bai, Xian Yang, Long Chen
Main category: cs.CV
TL;DR: LGDEA proposes an LLM-guided diagnostic evidence alignment method for medical vision-language pretraining that shifts from global/local alignment to evidence-level alignment using LLMs to extract diagnostic evidence from reports.
Details
Motivation: Existing CLIP-style medical VLP methods have limitations: global alignment is dominated by non-diagnostic information, local alignment fails to integrate key diagnostic evidence, and both require substantial paired data which limits applicability in medical scenarios with limited paired data.Method: LGDEA leverages LLMs to extract key diagnostic evidence from radiology reports and constructs a shared diagnostic evidence space, enabling evidence-aware cross-modal alignment. This allows effective exploitation of abundant unpaired medical images and reports, reducing reliance on paired data.
Result: The method achieves consistent and significant improvements on phrase grounding, image-text retrieval, and zero-shot classification tasks, and even rivals pretraining methods that rely on substantial paired data.
Conclusion: LGDEA successfully addresses limitations of existing medical VLP methods by introducing evidence-level alignment guided by LLMs, enabling more reliable diagnostic representations with reduced dependence on paired data.
Abstract: Most existing CLIP-style medical vision–language pretraining methods rely on global or local alignment with substantial paired data. However, global alignment is easily dominated by non-diagnostic information, while local alignment fails to integrate key diagnostic evidence. As a result, learning reliable diagnostic representations becomes difficult, which limits their applicability in medical scenarios with limited paired data. To address this issue, we propose an LLM-Guided Diagnostic Evidence Alignment method (LGDEA), which shifts the pretraining objective toward evidence-level alignment that is more consistent with the medical diagnostic process. Specifically, we leverage LLMs to extract key diagnostic evidence from radiology reports and construct a shared diagnostic evidence space, enabling evidence-aware cross-modal alignment and allowing LGDEA to effectively exploit abundant unpaired medical images and reports, thereby substantially alleviating the reliance on paired data. Extensive experimental results demonstrate that our method achieves consistent and significant improvements on phrase grounding, image–text retrieval, and zero-shot classification, and even rivals pretraining methods that rely on substantial paired data.
[259] MUFASA: A Multi-Layer Framework for Slot Attention
Sebastian Bock, Leonie Schüßler, Krishnakant Singh, Simone Schaub-Meyer, Stefan Roth
Main category: cs.CV
TL;DR: MUFASA improves unsupervised object segmentation by applying slot attention across multiple ViT layers instead of just the last layer, aggregating semantic information from different abstraction levels for better object-centric representations.
Details
Motivation: Current slot attention methods for unsupervised object-centric learning only use features from the last layer of pre-trained vision transformers, ignoring valuable semantic information encoded across other layers that could improve object segmentation.Method: MUFASA is a lightweight plug-and-play framework that computes slot attention across multiple feature layers of a ViT encoder, then uses a fusion strategy to aggregate slots from different layers into unified object-centric representations.
Result: Integrating MUFASA into existing OCL methods improves segmentation results across multiple datasets, sets new state-of-the-art performance, and improves training convergence with only minor inference overhead.
Conclusion: Leveraging multi-layer semantic information from ViTs through slot attention significantly enhances unsupervised object segmentation performance without substantial computational cost.
Abstract: Unsupervised object-centric learning (OCL) decomposes visual scenes into distinct entities. Slot attention is a popular approach that represents individual objects as latent vectors, called slots. Current methods obtain these slot representations solely from the last layer of a pre-trained vision transformer (ViT), ignoring valuable, semantically rich information encoded across the other layers. To better utilize this latent semantic information, we introduce MUFASA, a lightweight plug-and-play framework for slot attention-based approaches to unsupervised object segmentation. Our model computes slot attention across multiple feature layers of the ViT encoder, fully leveraging their semantic richness. We propose a fusion strategy to aggregate slots obtained on multiple layers into a unified object-centric representation. Integrating MUFASA into existing OCL methods improves their segmentation results across multiple datasets, setting a new state of the art while simultaneously improving training convergence with only minor inference overhead.
[260] Revealing the Semantic Selection Gap in DINOv3 through Training-Free Few-Shot Segmentation
Hussni Mohd Zakir, Eric Tatt Wei Ho
Main category: cs.CV
TL;DR: FSSDINO: A training-free few-shot semantic segmentation baseline using frozen DINOv3 features with class prototypes and Gram-matrix refinement, revealing a “Semantic Selection Gap” where optimal intermediate features outperform last-layer features but are hard to select.
Details
Motivation: To investigate the intrinsic few-shot semantic segmentation capabilities of frozen DINOv3 features and understand the gap between standard last-layer features and optimal intermediate representations in foundation models.Method: Proposes FSSDINO - a training-free baseline using frozen DINOv3 features with class-specific prototypes and Gram-matrix refinement. Conducts Oracle-guided layer analysis to identify optimal intermediate representations versus standard last-layer features.
Result: FSSDINO is highly competitive with specialized methods across binary, multi-class, and cross-domain benchmarks. Reveals a “Safest vs. Optimal” dilemma where Oracle-selected intermediate features outperform last-layer features, but current selection metrics fail to identify them reliably.
Conclusion: Establishes last-layer as a deceptively strong baseline while revealing a “Semantic Selection Gap” in foundation models where traditional heuristics fail to identify optimal features, highlighting untapped potential in intermediate representations.
Abstract: Recent self-supervised Vision Transformers (ViTs), such as DINOv3, provide rich feature representations for dense vision tasks. This study investigates the intrinsic few-shot semantic segmentation (FSS) capabilities of frozen DINOv3 features through a training-free baseline, FSSDINO, utilizing class-specific prototypes and Gram-matrix refinement. Our results across binary, multi-class, and cross-domain (CDFSS) benchmarks demonstrate that this minimal approach, applied to the final backbone layer, is highly competitive with specialized methods involving complex decoders or test-time adaptation. Crucially, we conduct an Oracle-guided layer analysis, identifying a significant performance gap between the standard last-layer features and globally optimal intermediate representations. We reveal a “Safest vs. Optimal” dilemma: while the Oracle proves higher performance is attainable, matching the results of compute-intensive adaptation methods, current unsupervised and support-guided selection metrics consistently yield lower performance than the last-layer baseline. This characterizes a “Semantic Selection Gap” in Foundation Models, a disconnect where traditional heuristics fail to reliably identify high-fidelity features. Our work establishes the “Last-Layer” as a deceptively strong baseline and provides a rigorous diagnostic of the latent semantic potentials in DINOv3.The code is publicly available at https://github.com/hussni0997/fssdino.
[261] FlexID: Training-Free Flexible Identity Injection via Intent-Aware Modulation for Text-to-Image Generation
Guandong Li, Yijun Ding
Main category: cs.CV
TL;DR: FlexID: Training-free personalized text-to-image generation framework using intent-aware modulation to balance identity fidelity and textual adaptability through orthogonal decoupling of identity features.
Details
Motivation: Existing training-free methods for personalized text-to-image generation rely on rigid visual feature injection, creating conflicts between identity fidelity and textual adaptability. There's a need for better balance between preserving specific identities and following textual descriptions.Method: FlexID uses intent-aware modulation with orthogonal decoupling: Semantic Identity Projector (SIP) injects high-level priors into language space, Visual Feature Anchor (VFA) ensures structural fidelity in latent space. Context-Aware Adaptive Gating (CAG) dynamically modulates weights based on editing intent and diffusion timesteps, relaxing visual constraints when strong editing is detected.
Result: Extensive experiments on IBench show FlexID achieves state-of-the-art balance between identity consistency and text adherence, offering efficient solution for complex narrative generation.
Conclusion: FlexID provides a novel training-free framework that achieves synergy between identity preservation and semantic variation through intent-aware modulation, addressing the fundamental conflict in personalized text-to-image generation.
Abstract: Personalized text-to-image generation aims to seamlessly integrate specific identities into textual descriptions. However, existing training-free methods often rely on rigid visual feature injection, creating a conflict between identity fidelity and textual adaptability. To address this, we propose FlexID, a novel training-free framework utilizing intent-aware modulation. FlexID orthogonally decouples identity into two dimensions: a Semantic Identity Projector (SIP) that injects high-level priors into the language space, and a Visual Feature Anchor (VFA) that ensures structural fidelity within the latent space. Crucially, we introduce a Context-Aware Adaptive Gating (CAG) mechanism that dynamically modulates the weights of these streams based on editing intent and diffusion timesteps. By automatically relaxing rigid visual constraints when strong editing intent is detected, CAG achieves synergy between identity preservation and semantic variation. Extensive experiments on IBench demonstrate that FlexID achieves a state-of-the-art balance between identity consistency and text adherence, offering an efficient solution for complex narrative generation.
[262] VISOR: VIsual Spatial Object Reasoning for Language-driven Object Navigation
Francesco Taioli, Shiping Yang, Sonia Raychaudhuri, Marco Cristani, Unnat Jain, Angel X Chang
Main category: cs.CV
TL;DR: A 3B-parameter Vision-Language-Action agent for language-driven object navigation that performs explicit image-grounded reasoning instead of embedding matching or modular pipelines
Details
Motivation: Existing methods for language-driven object navigation either use end-to-end trained models that lack explainability and generalization, or modular pipelines with LLMs and object detectors that suffer from error propagation and high computational costMethod: Proposes a compact 3B-parameter VLA agent that performs human-like embodied reasoning through explicit image-grounded reasoning in three stages: “think”, “think summary”, and “action”
Result: The agent yields improved explainability, stronger generalization, and more efficient navigation compared to existing approaches
Conclusion: The proposed VLA agent provides a more effective approach to language-driven object navigation by combining explicit reasoning with efficient parameter usage
Abstract: Language-driven object navigation requires agents to interpret natural language descriptions of target objects, which combine intrinsic and extrinsic attributes for instance recognition and commonsense navigation. Existing methods either (i) use end-to-end trained models with vision-language embeddings, which struggle to generalize beyond training data and lack action-level explainability, or (ii) rely on modular zero-shot pipelines with large language models (LLMs) and open-set object detectors, which suffer from error propagation, high computational cost, and difficulty integrating their reasoning back into the navigation policy. To this end, we propose a compact 3B-parameter Vision-Language-Action (VLA) agent that performs human-like embodied reasoning for both object recognition and action selection, removing the need for stitched multi-model pipelines. Instead of raw embedding matching, our agent employs explicit image-grounded reasoning to directly answer “Is this the target object?” and “Why should I take this action?” The reasoning process unfolds in three stages: “think”, “think summary”, and “action”, yielding improved explainability, stronger generalization, and more efficient navigation. Code and dataset available upon acceptance.
[263] SIGMA: Selective-Interleaved Generation with Multi-Attribute Tokens
Xiaoyan Zhang, Zechen Bai, Haofan Wang, Yiren Song
Main category: cs.CV
TL;DR: SIGMA is a unified post-training framework that enables interleaved multi-condition generation in diffusion transformers, allowing compositional editing and selective attribute transfer through multi-attribute tokens.
Details
Motivation: Existing unified models like Bagel are limited to single-condition inputs and lack flexibility for synthesizing results from multiple heterogeneous sources. There's a need for models that can interpret and compose multiple visual conditions in an interleaved manner.Method: SIGMA introduces selective multi-attribute tokens (style, content, subject, identity) and uses post-training on the Bagel backbone with 700K interleaved examples. It enables the model to process interleaved text-image sequences for multi-condition generation.
Result: SIGMA improves controllability, cross-condition consistency, and visual quality across diverse editing and generation tasks, with substantial gains over Bagel on compositional tasks.
Conclusion: SIGMA provides a flexible unified framework for interleaved multi-condition generation in diffusion transformers, enabling more sophisticated compositional editing and attribute transfer capabilities.
Abstract: Recent unified models such as Bagel demonstrate that paired image-edit data can effectively align multiple visual tasks within a single diffusion transformer. However, these models remain limited to single-condition inputs and lack the flexibility needed to synthesize results from multiple heterogeneous sources. We present SIGMA (Selective-Interleaved Generation with Multi-Attribute Tokens), a unified post-training framework that enables interleaved multi-condition generation within diffusion transformers. SIGMA introduces selective multi-attribute tokens, including style, content, subject, and identity tokens, which allow the model to interpret and compose multiple visual conditions in an interleaved text-image sequence. Through post-training on the Bagel unified backbone with 700K interleaved examples, SIGMA supports compositional editing, selective attribute transfer, and fine-grained multimodal alignment. Extensive experiments show that SIGMA improves controllability, cross-condition consistency, and visual quality across diverse editing and generation tasks, with substantial gains over Bagel on compositional tasks.
[264] Human Identification at a Distance: Challenges, Methods and Results on the Competition HID 2025
Jingzhe Ma, Meng Zhang, Jianlong Yu, Kun Liu, Zunxiao Xu, Xue Cheng, Junjie Zhou, Yanfei Wang, Jiahang Li, Zepeng Wang, Kazuki Osamura, Rujie Liu, Narishige Abe, Jingjie Wang, Shunli Zhang, Haojun Xie, Jiajun Wu, Weiming Wu, Wenxiong Kang, Qingshuo Gao, Jiaming Xiong, Xianye Ben, Lei Chen, Lichen Song, Junjian Cui, Haijun Xiong, Junhao Lu, Bin Feng, Mengyuan Liu, Ji Zhou, Baoquan Zhao, Ke Xu, Yongzhen Huang, Liang Wang, Manuel J Marin-Jimenez, Md Atiqur Rahman Ahad, Shiqi Yu
Main category: cs.CV
TL;DR: HID 2025 competition on gait recognition using SUSTech-Competition dataset, where best method achieved 94.2% accuracy despite challenging variations in clothing, carried objects, and view angles.
Details
Motivation: To advance gait recognition as a practical alternative for human identification at distance when traditional biometrics (face, fingerprints) are unavailable, and to provide fair evaluation through annual competitions with challenging datasets.Method: Annual competition using SUSTech-Competition dataset with substantial variations (clothing, carried objects, view angles), no dedicated training data provided (external datasets only), different random seeds each year for evaluation splits to prevent overfitting.
Result: Best-performing method reached 94.2% accuracy, setting new benchmark on this challenging dataset, demonstrating algorithmic advances can surpass previous accuracy limits despite heightened difficulty.
Conclusion: Gait recognition continues to advance with algorithmic improvements, competition framework effectively promotes progress and fair evaluation, and future research directions are outlined for the field.
Abstract: Human identification at a distance (HID) is challenging because traditional biometric modalities such as face and fingerprints are often difficult to acquire in real-world scenarios. Gait recognition provides a practical alternative, as it can be captured reliably at a distance. To promote progress in gait recognition and provide a fair evaluation platform, the International Competition on Human Identification at a Distance (HID) has been organized annually since 2020. Since 2023, the competition has adopted the challenging SUSTech-Competition dataset, which features substantial variations in clothing, carried objects, and view angles. No dedicated training data are provided, requiring participants to train their models using external datasets. Each year, the competition applies a different random seed to generate distinct evaluation splits, which reduces the risk of overfitting and supports a fair assessment of cross-domain generalization. While HID 2023 and HID 2024 already used this dataset, HID 2025 explicitly examined whether algorithmic advances could surpass the accuracy limits observed previously. Despite the heightened difficulty, participants achieved further improvements, and the best-performing method reached 94.2% accuracy, setting a new benchmark on this dataset. We also analyze key technical trends and outline potential directions for future research in gait recognition.
[265] Cross-Camera Cow Identification via Disentangled Representation Learning
Runcheng Wang, Yaru Chen, Guiguo Zhang, Honghua Jiang, Yongliang Qiao
Main category: cs.CV
TL;DR: A cross-camera cow identification framework using disentangled representation learning to improve generalization across different camera nodes in smart farming environments.
Details
Motivation: Existing animal identification methods work well in controlled single-camera settings but fail to generalize across different cameras with varying illumination, backgrounds, viewpoints, and imaging properties, limiting large-scale application in real-world farming.Method: Proposes a cross-camera cow identification framework based on disentangled representation learning using Subspace Identifiability Guarantee (SIG) theory. Designs a feature disentanglement module that decomposes images into orthogonal latent subspaces to isolate stable, identity-related biometric features invariant across cameras.
Result: Achieves 86.0% average accuracy across seven cross-camera tasks, significantly outperforming Source-only Baseline (51.9%) and strongest cross-camera baseline (79.8%). Validated on a dataset spanning five distinct camera nodes with heterogeneous devices and complex variations.
Conclusion: Establishes a subspace-theoretic feature disentanglement framework for collaborative cross-camera cow identification, offering a new paradigm for precise animal monitoring in uncontrolled smart farming environments.
Abstract: Precise identification of individual cows is a fundamental prerequisite for comprehensive digital management in smart livestock farming. While existing animal identification methods excel in controlled, single-camera settings, they face severe challenges regarding cross-camera generalization. When models trained on source cameras are deployed to new monitoring nodes characterized by divergent illumination, backgrounds, viewpoints, and heterogeneous imaging properties, recognition performance often degrades dramatically. This limits the large-scale application of non-contact technologies in dynamic, real-world farming environments. To address this challenge, this study proposes a cross-camera cow identification framework based on disentangled representation learning. This framework leverages the Subspace Identifiability Guarantee (SIG) theory in the context of bovine visual recognition. By modeling the underlying physical data generation process, we designed a principle-driven feature disentanglement module that decomposes observed images into multiple orthogonal latent subspaces. This mechanism effectively isolates stable, identity-related biometric features that remain invariant across cameras, thereby substantially improving generalization to unseen cameras. We constructed a high-quality dataset spanning five distinct camera nodes, covering heterogeneous acquisition devices and complex variations in lighting and angles. Extensive experiments across seven cross-camera tasks demonstrate that the proposed method achieves an average accuracy of 86.0%, significantly outperforming the Source-only Baseline (51.9%) and the strongest cross-camera baseline method (79.8%). This work establishes a subspace-theoretic feature disentanglement framework for collaborative cross-camera cow identification, offering a new paradigm for precise animal monitoring in uncontrolled smart farming environments.
[266] Visualizing the Invisible: Enhancing Radiologist Performance in Breast Mammography via Task-Driven Chromatic Encoding
Hui Ye, Shilong Yang, Yexuan Xing, Juan Yu, Yaoqin Xie, Wei Zhang, Chulong Zhang
Main category: cs.CV
TL;DR: MammoColor is an end-to-end framework with Task-Driven Chromatic Encoding (TDCE) that converts single-channel mammograms into color-encoded views to improve breast cancer detection in dense breasts, showing improved AUC and specificity.
Details
Motivation: Mammography screening is less sensitive in dense breasts due to tissue overlap and subtle findings that increase perceptual difficulty. There's a need for better visualization techniques to improve detection accuracy.Method: MammoColor uses a lightweight Task-Driven Chromatic Encoding (TDCE) module coupled with a BI-RADS triage classifier, trained end-to-end on VinDr-Mammo dataset. The framework converts single-channel mammograms into TDCE-encoded color views for visual augmentation.
Result: On VinDr-Mammo, MammoColor improved AUC from 0.7669 to 0.8461 (P=0.004), with larger gains in dense breasts (AUC 0.749 to 0.835). In MRMC observer studies, TDCE-encoded images improved specificity from 0.90 to 0.96 with comparable sensitivity.
Conclusion: TDCE provides a task-optimized chromatic representation that improves perceptual salience and reduces false-positive recalls in mammography triage, particularly beneficial for dense breast screening.
Abstract: Purpose:Mammography screening is less sensitive in dense breasts, where tissue overlap and subtle findings increase perceptual difficulty. We present MammoColor, an end-to-end framework with a Task-Driven Chromatic Encoding (TDCE) module that converts single-channel mammograms into TDCE-encoded views for visual augmentation. Materials and Methods:MammoColor couples a lightweight TDCE module with a BI-RADS triage classifier and was trained end-to-end on VinDr-Mammo. Performance was evaluated on an internal test set, two public datasets (CBIS-DDSM and INBreast), and three external clinical cohorts. We also conducted a multi-reader, multi-case (MRMC) observer study with a washout period, comparing (1) grayscale-only, (2) TDCE-only, and (3) side-by-side grayscale+TDCE. Results:On VinDr-Mammo, MammoColor improved AUC from 0.7669 to 0.8461 (P=0.004). Gains were larger in dense breasts (AUC 0.749 to 0.835). In the MRMC study, TDCE-encoded images improved specificity (0.90 to 0.96; P=0.052) with comparable sensitivity. Conclusion:TDCE provides a task-optimized chromatic representation that may improve perceptual salience and reduce false-positive recalls in mammography triage.
[267] ViCA: Efficient Multimodal LLMs with Vision-Only Cross-Attention
Wenjie Liu, Hao Wu, Xin Qiu, Yingqi Fan, Yihan Zhang, Anhao Zhao, Yunpu Ma, Xiaoyu Shen
Main category: cs.CV
TL;DR: ViCA is a minimal MLLM architecture that uses sparse cross-attention instead of dense visual processing, reducing visual-side computation to 4% while preserving 98% of baseline accuracy.
Details
Motivation: Current MLLMs use dense visual processing through self-attention at every layer, which is computationally expensive. The authors found that visual embeddings are already well-aligned with language space and effective vision-language interaction occurs only in a small subset of layers.Method: ViCA bypasses visual tokens through all self-attention and feed-forward layers, interacting with text solely through sparse cross-attention at selected layers. This creates a regular, hardware-friendly inference pipeline.
Result: ViCA achieves 98% of baseline accuracy while reducing visual-side computation to 4%, with over 3.5x speedup in single-batch inference and over 10x speedup in multi-batch inference. It’s orthogonal to token pruning methods and can be combined for further efficiency gains.
Conclusion: ViCA demonstrates that dense visual processing in MLLMs is unnecessary and proposes an efficient alternative that maintains performance while dramatically reducing computational overhead.
Abstract: Modern multimodal large language models (MLLMs) adopt a unified self-attention design that processes visual and textual tokens at every Transformer layer, incurring substantial computational overhead. In this work, we revisit the necessity of such dense visual processing and show that projected visual embeddings are already well-aligned with the language space, while effective vision-language interaction occurs in only a small subset of layers. Based on these insights, we propose ViCA (Vision-only Cross-Attention), a minimal MLLM architecture in which visual tokens bypass all self-attention and feed-forward layers, interacting with text solely through sparse cross-attention at selected layers. Extensive evaluations across three MLLM backbones, nine multimodal benchmarks, and 26 pruning-based baselines show that ViCA preserves 98% of baseline accuracy while reducing visual-side computation to 4%, consistently achieving superior performance-efficiency trade-offs. Moreover, ViCA provides a regular, hardware-friendly inference pipeline that yields over 3.5x speedup in single-batch inference and over 10x speedup in multi-batch inference, reducing visual grounding to near-zero overhead compared with text-only LLMs. It is also orthogonal to token pruning methods and can be seamlessly combined for further efficiency gains. Our code is available at https://github.com/EIT-NLP/ViCA.
[268] Automated rock joint trace mapping using a supervised learning model trained on synthetic data generated by parametric modelling
Jessica Ka Yi Chiu, Tom Frode Hansen, Eivind Magnus Paulsen, Ole Jakob Mengshoel
Main category: cs.CV
TL;DR: A geology-driven ML method for automated rock joint trace mapping from images using synthetic data generation and supervised segmentation to overcome limited real data and class imbalance.
Details
Motivation: Limited real data and class imbalance in rock joint trace mapping from images, requiring geological modeling and synthetic data to address these challenges.Method: Combines discrete fracture network models for synthetic image generation, mixed training with synthetic data, pretraining, and fine-tuning on real images for segmentation.
Result: Synthetic data supports joint trace detection when real data is scarce; mixed training works with consistent labels, fine-tuning handles noisy labels; zero-shot prediction limited but fine-tuning with small real data achieves useful generalization.
Conclusion: The method enables reliable joint mapping and provides foundation for domain adaptation and evaluation, with qualitative analysis showing geologically meaningful results beyond quantitative metrics.
Abstract: This paper presents a geology-driven machine learning method for automated rock joint trace mapping from images. The approach combines geological modelling, synthetic data generation, and supervised image segmentation to address limited real data and class imbalance. First, discrete fracture network models are used to generate synthetic jointed rock images at field-relevant scales via parametric modelling, preserving joint persistence, connectivity, and node-type distributions. Second, segmentation models are trained using mixed training and pretraining followed by fine-tuning on real images. The method is tested in box and slope domains using several real datasets. The results show that synthetic data can support supervised joint trace detection when real data are scarce. Mixed training performs well when real labels are consistent (e.g. box-domain), while fine-tuning is more robust when labels are noisy (e.g. slope-domain where labels can be biased, incomplete, and inconsistent). Fully zero-shot prediction from synthetic model remains limited, but useful generalisation is achieved by fine-tuning with a small number of real data. Qualitative analysis shows clearer and more geologically meaningful joint traces than indicated by quantitative metrics alone. The proposed method supports reliable joint mapping and provides a basis for further work on domain adaptation and evaluation.
[269] TeleBoost: A Systematic Alignment Framework for High-Fidelity, Controllable, and Robust Video Generation
Yuanzhi Liang, Xuan’er Wu, Yirui Liu, Yijie Fang, Yizhen Fan, Ke Hao, Rui Li, Ruiying Liu, Ziqi Ni, Peng Yu, Yanbo Wang, Haibin Huang, Qizhen Weng, Chi Zhang, Xuelong Li
Main category: cs.CV
TL;DR: Systematic post-training framework for video generators combining supervised policy shaping, reward-driven RL, and preference-based refinement into stability-constrained optimization for production-ready models.
Details
Motivation: Post-training is crucial for converting pretrained video generators into production models that are instruction-following, controllable, and robust over long temporal horizons, but faces challenges like high rollout costs, temporally compounding failures, and heterogeneous feedback.Method: A systematic framework organizing supervised policy shaping, reward-driven reinforcement learning, and preference-based refinement into a single stability-constrained optimization stack, treating optimization as staged diagnostic-driven process rather than isolated tricks.
Result: Provides a cohesive recipe for improving perceptual fidelity, temporal coherence, and prompt adherence while preserving controllability, offering a blueprint for scalable post-training pipelines that remain stable and effective in real-world deployment.
Conclusion: The framework enables building scalable post-training pipelines for video generators that are stable, extensible, and effective for real-world deployment by systematically addressing practical constraints and optimization challenges.
Abstract: Post-training is the decisive step for converting a pretrained video generator into a production-oriented model that is instruction-following, controllable, and robust over long temporal horizons. This report presents a systematical post-training framework that organizes supervised policy shaping, reward-driven reinforcement learning, and preference-based refinement into a single stability-constrained optimization stack. The framework is designed around practical video-generation constraints, including high rollout cost, temporally compounding failure modes, and feedback that is heterogeneous, uncertain, and often weakly discriminative. By treating optimization as a staged, diagnostic-driven process rather than a collection of isolated tricks, the report summarizes a cohesive recipe for improving perceptual fidelity, temporal coherence, and prompt adherence while preserving the controllability established at initialization. The resulting framework provides a clear blueprint for building scalable post-training pipelines that remain stable, extensible, and effective in real-world deployment settings.
[270] Fine-R1: Make Multi-modal LLMs Excel in Fine-Grained Visual Recognition by Chain-of-Thought Reasoning
Hulingxiao He, Zijun Geng, Yuxin Peng
Main category: cs.CV
TL;DR: Fine-R1 is a multimodal large language model specifically designed for fine-grained visual recognition through a two-stage R1-style training framework that improves performance on both seen and unseen sub-categories with minimal training data.
Details
Motivation: Current MLLMs struggle with fine-grained visual recognition, requiring large annotated datasets and suffering from poor generalization to unseen sub-categories, creating a performance gap compared to specialized contrastive CLIP models.Method: Two-stage R1-style framework: (1) Chain-of-Thought Supervised Fine-tuning using a constructed FGVR CoT dataset with rationales, and (2) Triplet Augmented Policy Optimization with intra-class augmentation (mixing trajectories within same category) and inter-class augmentation (maximizing response distinction across sub-categories).
Result: With only 4-shot training, Fine-R1 outperforms existing general MLLMs, reasoning MLLMs, and contrastive CLIP models in identifying both seen and unseen sub-categories.
Conclusion: Fine-R1 shows promise for knowledge-intensive domains where gathering expert annotations for all sub-categories is difficult, demonstrating effective adaptation of MLLMs to fine-grained visual recognition tasks.
Abstract: Any entity in the visual world can be hierarchically grouped based on shared characteristics and mapped to fine-grained sub-categories. While Multi-modal Large Language Models (MLLMs) achieve strong performance on coarse-grained visual tasks, they often struggle with Fine-Grained Visual Recognition (FGVR). Adapting general-purpose MLLMs to FGVR typically requires large amounts of annotated data, which is costly to obtain, leaving a substantial performance gap compared to contrastive CLIP models dedicated for discriminative tasks. Moreover, MLLMs tend to overfit to seen sub-categories and generalize poorly to unseen ones. To address these challenges, we propose Fine-R1, an MLLM tailored for FGVR through an R1-style training framework: (1) Chain-of-Thought Supervised Fine-tuning, where we construct a high-quality FGVR CoT dataset with rationales of “visual analysis, candidate sub-categories, comparison, and prediction”, transition the model into a strong open-world classifier; and (2) Triplet Augmented Policy Optimization, where Intra-class Augmentation mixes trajectories from anchor and positive images within the same category to improve robustness to intra-class variance, while Inter-class Augmentation maximizes the response distinction conditioned on images across sub-categories to enhance discriminative ability. With only 4-shot training, Fine-R1 outperforms existing general MLLMs, reasoning MLLMs, and even contrastive CLIP models in identifying both seen and unseen sub-categories, showing promise in working in knowledge-intensive domains where gathering expert annotations for all sub-categories is arduous. Code is available at https://github.com/PKU-ICST-MIPL/FineR1_ICLR2026.
[271] HistoMet: A Pan-Cancer Deep Learning Framework for Prognostic Prediction of Metastatic Progression and Site Tropism from Primary Tumor Histopathology
Yixin Chen, Ziyu Su, Lingbin Meng, Elshad Hasanov, Wei Chen, Anil Parwani, M. Khalid Khan Niazi
Main category: cs.CV
TL;DR: HistoMet: A decision-aware, concept-aligned MIL framework for predicting metastatic progression and site dissemination from primary tumor whole-slide images using a two-module pipeline with pathology vision-language model guidance.
Details
Motivation: Metastatic progression is the leading cause of cancer mortality, but predicting metastasis and dissemination sites directly from histopathology remains challenging. Current approaches treat metastatic status and site prediction as isolated tasks rather than modeling the clinical sequential decision process.Method: Proposes HistoMet, a decision-aware, concept-aligned multiple instance learning framework with a two-module pipeline: 1) estimates likelihood of metastatic progression from primary tumor, 2) conditionally predicts metastatic site for high-risk cases. Integrates linguistically defined and data-adaptive metastatic concepts through a pretrained pathology vision-language model.
Result: Evaluated on multi-institutional pan-cancer cohort of 6504 patients. Under 95% sensitivity screening settings, significantly reduces downstream workload while maintaining high metastatic risk recall. For metastatic cases, achieves macro F1 of 74.6±1.3 and macro one-vs-rest AUC of 92.1.
Conclusion: Explicitly modeling clinical decision structure enables robust and deployable prognostic prediction of metastatic progression and site tropism directly from primary tumor histopathology.
Abstract: Metastatic Progression remains the leading cause of cancer-related mortality, yet predicting whether a primary tumor will metastasize and where it will disseminate directly from histopathology remains a fundamental challenge. Although whole-slide images (WSIs) provide rich morphological information, prior computational pathology approaches typically address metastatic status or site prediction as isolated tasks, and do not explicitly model the clinically sequential decision process of metastatic risk assessment followed by downstream site-specific evaluation. To address this research gap, we present a decision-aware, concept-aligned MIL framework, HistoMet, for prognostic metastatic outcome prediction from primary tumor WSIs. Our proposed framework adopts a two-module prediction pipeline in which the likelihood of metastatic progression from the primary tumor is first estimated, followed by conditional prediction of metastatic site for high-risk cases. To guide representation learning and improve clinical interpretability, our framework integrates linguistically defined and data-adaptive metastatic concepts through a pretrained pathology vision-language model. We evaluate HistoMet on a multi-institutional pan-cancer cohort of 6504 patients with metastasis follow-up and site annotations. Under clinically relevant high-sensitivity screening settings (95 percent sensitivity), HistoMet significantly reduces downstream workload while maintaining high metastatic risk recall. Conditional on metastatic cases, HistoMet achieves a macro F1 of 74.6 with a standard deviation of 1.3 and a macro one-vs-rest AUC of 92.1. These results demonstrate that explicitly modeling clinical decision structure enables robust and deployable prognostic prediction of metastatic progression and site tropism directly from primary tumor histopathology.
[272] AD-MIR: Bridging the Gap from Perception to Persuasion in Advertising Video Understanding via Structured Reasoning
Binxiao Xu, Junyu Feng, Xiaopeng Lin, Haodong Li, Zhiyuan Feng, Bohan Zeng, Shaolin Lu, Ming Lu, Qi She, Wentao Zhang
Main category: cs.CV
TL;DR: AD-MIR is a two-stage framework for understanding advertising videos by bridging pixel-level perception with high-level marketing logic through structured memory construction and evidence-based reasoning.
Details
Motivation: Existing multimodal agents struggle to bridge the cognitive gap between pixel-level perception and high-level marketing logic in advertising videos, despite excelling at general search tasks.Method: Two-stage architecture: 1) Structure-Aware Memory Construction converts raw video into structured database using semantic retrieval and keyword matching, focusing on brand details while filtering noise; 2) Structured Reasoning Agent mimics marketing expert through iterative inquiry loop with evidence-based self-correction that validates insights against specific video frames.
Result: AD-MIR achieves state-of-the-art performance on AdsQA benchmark, surpassing the strongest general-purpose agent DVD by 1.8% in strict accuracy and 9.5% in relaxed accuracy.
Conclusion: Effective advertising understanding requires explicitly grounding abstract marketing strategies in pixel-level evidence, which AD-MIR successfully accomplishes through its structured approach.
Abstract: Multimodal understanding of advertising videos is essential for interpreting the intricate relationship between visual storytelling and abstract persuasion strategies. However, despite excelling at general search, existing agents often struggle to bridge the cognitive gap between pixel-level perception and high-level marketing logic. To address this challenge, we introduce AD-MIR, a framework designed to decode advertising intent via a two-stage architecture. First, in the Structure-Aware Memory Construction phase, the system converts raw video into a structured database by integrating semantic retrieval with exact keyword matching. This approach prioritizes fine-grained brand details (e.g., logos, on-screen text) while dynamically filtering out irrelevant background noise to isolate key protagonists. Second, the Structured Reasoning Agent mimics a marketing expert through an iterative inquiry loop, decomposing the narrative to deduce implicit persuasion tactics. Crucially, it employs an evidence-based self-correction mechanism that rigorously validates these insights against specific video frames, automatically backtracking when visual support is lacking. Evaluation on the AdsQA benchmark demonstrates that AD-MIR achieves state-of-the-art performance, surpassing the strongest general-purpose agent, DVD, by 1.8% in strict and 9.5% in relaxed accuracy. These results underscore that effective advertising understanding demands explicitly grounding abstract marketing strategies in pixel-level evidence. The code is available at https://github.com/Little-Fridge/AD-MIR.
[273] Uncovering Modality Discrepancy and Generalization Illusion for General-Purpose 3D Medical Segmentation
Yichi Zhang, Feiyang Xiao, Le Xue, Wenbo Zhang, Gang Feng, Chenguang Zheng, Yuan Qi, Yuan Cheng, Zixin Hu
Main category: cs.CV
TL;DR: 3D medical foundation models show significant performance degradation when applied to functional imaging modalities (PET) compared to structural imaging (CT/MRI), revealing a modality gap that challenges their general-purpose claims.
Details
Motivation: Current 3D medical foundation models are validated primarily on structural imaging (CT/MRI), but their performance on functional imaging (PET) remains unexplored. There's a need to assess whether these models are truly general-purpose across different imaging modalities.Method: Created UMD dataset with 490 PET/CT and 464 PET/MRI scans (~675k 2D images, ~12k 3D organ annotations). Conducted intra-subject controlled comparisons using paired scans to isolate modality as the independent variable. Evaluated representative 3D segmentation foundation models on this dataset.
Result: Found stark discrepancy between literature-reported benchmarks and real-world efficacy, especially when transitioning from structural to functional domains. Models showed systemic failures on PET imaging despite good performance on CT/MRI.
Conclusion: Current 3D foundation models are not truly general-purpose and require multi-modal training and evaluation to bridge the gap between idealized benchmarking and comprehensive clinical utility. The UMD dataset provides a foundation for developing modality-agnostic medical foundation models.
Abstract: While emerging 3D medical foundation models are envisioned as versatile tools with offer general-purpose capabilities, their validation remains largely confined to regional and structural imaging, leaving a significant modality discrepancy unexplored. To provide a rigorous and objective assessment, we curate the UMD dataset comprising 490 whole-body PET/CT and 464 whole-body PET/MRI scans ($\sim$675k 2D images, $\sim$12k 3D organ annotations) and conduct a thorough and comprehensive evaluation of representative 3D segmentation foundation models. Through intra-subject controlled comparisons of paired scans, we isolate imaging modality as the primary independent variable to evaluate model robustness in real-world applications. Our evaluation reveals a stark discrepancy between literature-reported benchmarks and real-world efficacy, particularly when transitioning from structural to functional domains. Such systemic failures underscore that current 3D foundation models are far from achieving truly general-purpose status, necessitating a paradigm shift toward multi-modal training and evaluation to bridge the gap between idealized benchmarking and comprehensive clinical utility. This dataset and analysis establish a foundational cornerstone for future research to develop truly modality-agnostic medical foundation models.
[274] From Dead Pixels to Editable Slides: Infographic Reconstruction into Native Google Slides via Vision-Language Region Understanding
Leonardo Gonzalez
Main category: cs.CV
TL;DR: Images2Slides converts static infographic images into editable Google Slides by extracting region-level specifications using vision-language models and reconstructing elements via API.
Details
Motivation: Infographics are commonly exported as static images, making updates, localization, and reuse expensive. The paper aims to unlock this content by converting pixel-based infographics into editable slide formats.Method: Uses a vision-language model (VLM) to extract region-level specifications from infographic images, maps pixel geometry to slide coordinates, and recreates elements using Google Slides batch update API. The system is model-agnostic with multiple VLM backends via common JSON schema.
Result: Achieves 98.9% element recovery rate on benchmark of 29 programmatically generated infographics, with high text transcription accuracy (CER=0.033) and good layout fidelity (IoU=0.364 for text, 0.644 for images).
Conclusion: Demonstrates successful conversion of static infographics to editable slides using VLMs, identifies practical engineering challenges (text size calibration, backgrounds), and provides failure modes for future work.
Abstract: Infographics are widely used to communicate information with a combination of text, icons, and data visualizations, but once exported as images their content is locked into pixels, making updates, localization, and reuse expensive. We describe \textsc{Images2Slides}, an API-based pipeline that converts a static infographic (PNG/JPG) into a native, editable Google Slides slide by extracting a region-level specification with a vision-language model (VLM), mapping pixel geometry into slide coordinates, and recreating elements using the Google Slides batch update API. The system is model-agnostic and supports multiple VLM backends via a common JSON region schema and deterministic postprocessing. On a controlled benchmark of 29 programmatically generated infographic slides with known ground-truth regions, \textsc{Images2Slides} achieves an overall element recovery rate of $0.989\pm0.057$ (text: $0.985\pm0.083$, images: $1.000\pm0.000$), with mean text transcription error $\mathrm{CER}=0.033\pm0.149$ and mean layout fidelity $\mathrm{IoU}=0.364\pm0.161$ for text regions and $0.644\pm0.131$ for image regions. We also highlight practical engineering challenges in reconstruction, including text size calibration and non-uniform backgrounds, and describe failure modes that guide future work.
[275] Influence of Geometry, Class Imbalance and Alignment on Reconstruction Accuracy – A Micro-CT Phantom-Based Evaluation
Avinash Kumar K M, Samarth S. Raut
Main category: cs.CV
TL;DR: Evaluation of 3D medical model reconstruction accuracy comparing voxel-based and surface-based metrics for different segmentation methods and geometries, finding Otsu generally best but class imbalance and alignment issues affect results.
Details
Motivation: To thoroughly explore how geometry type, class imbalance, voxel/point cloud alignment affect 3D medical model accuracy, and evaluate errors across the reconstruction pipeline using different accuracy metrics.Method: Printed sphere, facemask, and AAA models using SLA, scanned with micro-CT, segmented using GMM, Otsu, and RG methods, aligned with KU algorithm, compared using Dice/Jaccard scores and surface metrics like chamfer/Hausdorff distances.
Result: Otsu method most suitable for all geometries; AAA had low overlap scores due to thin walls and misalignment; class imbalance affected specificity most for AAA; surface metrics differed from voxel-based trends; RG best for sphere, GMM/Otsu better for AAA.
Conclusion: Segmentation accuracy accumulates errors across reconstruction stages; high voxel-based metrics can be misleading with class imbalance and alignment issues; Jaccard more stringent than Dice for thin-walled structures; proper alignment crucial for reliable assessment.
Abstract: The accuracy of the 3D models created from medical scans depends on imaging hardware, segmentation methods and mesh processing techniques etc. The effects of geometry type, class imbalance, voxel and point cloud alignment on accuracy remain to be thoroughly explored. This work evaluates the errors across the reconstruction pipeline and explores the use of voxel and surface-based accuracy metrics for different segmentation algorithms and geometry types. A sphere, a facemask, and an AAA were printed using the SLA technique and scanned using a micro-CT machine. Segmentation was performed using GMM, Otsu and RG based methods. Segmented and reference models aligned using the KU algorithm, were quantitatively compared to evaluate metrics like Dice and Jaccard scores, precision. Surface meshes were registered with reference meshes using an ICP-based alignment process. Metrics like chamfer distance, and average Hausdorff distance were evaluated. The Otsu method was found to be the most suitable method for all the geometries. AAA yielded low overlap scores due to its small wall thickness and misalignment. The effect of class imbalance on specificity was observed the most for AAA. Surface-based accuracy metrics differed from the voxel-based trends. The RG method performed best for sphere, while GMM and Otsu perform better for AAA. The facemask surface was most error-prone, possibly due to misalignment during the ICP process. Segmentation accuracy is a cumulative sum of errors across different stages of the reconstruction process. High voxel-based accuracy metrics may be misleading in cases of high class imbalance and sensitivity to alignment. The Jaccard index is found to be more stringent than the Dice and more suitable for accuracy assessment for thin-walled structures. Voxel and point cloud alignment should be ensured to make any reliable assessment of the reconstruction pipeline.
[276] Looking and Listening Inside and Outside: Multimodal Artificial Intelligence Systems for Driver Safety Assessment and Intelligent Vehicle Decision-Making
Ross Greer, Laura Fleig, Maitrayee Keskar, Erika Maquiling, Giovanni Tapia Lopez, Angel Martinez-Sanchez, Parthib Roy, Jake Rattigan, Mira Sur, Alejandra Vidrio, Thomas Marcotte, Mohan Trivedi
Main category: cs.CV
TL;DR: L-LIO framework extends LILO by adding audio modality to understand driver/passenger states and external environment through multimodal audio-visual fusion for vehicle safety applications.
Details
Motivation: Current LILO framework focuses on visual understanding of outside scenes and driver states, but audio provides additional crucial information about driver impairment, passenger instructions, and external agent guidance that vision alone cannot capture, especially in safety-critical scenarios.Method: Proposes L-LIO framework that incorporates audio signals alongside visual data. Evaluates three use cases: 1) supervised learning on driver speech to classify impairment states, 2) collection/analysis of passenger natural language instructions for planning systems, 3) audio disambiguation of external agent guidance where vision is insufficient. Uses custom-collected in-vehicle and external audio datasets.
Result: Pilot findings show audio yields safety-relevant insights in nuanced scenarios where sound is critical to safe decision-making or visual signals alone are insufficient. Audio enhances understanding of driver states, passenger intentions, and external guidance.
Conclusion: L-LIO augments driver and scene understanding through multimodal fusion of audio and visual sensing, offering new paths for safety intervention, though challenges remain with ambient noise, privacy, and robustness across subjects in dynamic real-world contexts.
Abstract: The looking-in-looking-out (LILO) framework has enabled intelligent vehicle applications that understand both the outside scene and the driver state to improve safety outcomes, with examples in smart airbag deployment, takeover time prediction in autonomous control transitions, and driver attention monitoring. In this research, we propose an augmentation to this framework, making a case for the audio modality as an additional source of information to understand the driver, and in the evolving autonomy landscape, also the passengers and those outside the vehicle. We expand LILO by incorporating audio signals, forming the looking-and-listening inside-and-outside (L-LIO) framework to enhance driver state assessment and environment understanding through multimodal sensor fusion. We evaluate three example cases where audio enhances vehicle safety: supervised learning on driver speech audio to classify potential impairment states (e.g., intoxication), collection and analysis of passenger natural language instructions (e.g., “turn after that red building”) to motivate how spoken language can interface with planning systems through audio-aligned instruction data, and limitations of vision-only systems where audio may disambiguate the guidance and gestures of external agents. Datasets include custom-collected in-vehicle and external audio samples in real-world environments. Pilot findings show that audio yields safety-relevant insights, particularly in nuanced or context-rich scenarios where sound is critical to safe decision-making or visual signals alone are insufficient. Challenges include ambient noise interference, privacy considerations, and robustness across human subjects, motivating further work on reliability in dynamic real-world contexts. L-LIO augments driver and scene understanding through multimodal fusion of audio and visual sensing, offering new paths for safety intervention.
[277] Vision and language: Novel Representations and Artificial intelligence for Driving Scene Safety Assessment and Autonomous Vehicle Planning
Ross Greer, Maitrayee Keskar, Angel Martinez-Sanchez, Parthib Roy, Shashank Shriram, Mohan Trivedi
Main category: cs.CV
TL;DR: VLMs show promise for autonomous driving safety through semantic hazard detection, trajectory planning integration, and natural language behavioral constraints, but require careful system design rather than direct feature injection.
Details
Motivation: Vision-language models offer new opportunities for semantic reasoning in safety-critical autonomous driving by aligning visual observations with natural language concepts, potentially improving safety assessment and decision-making.Method: Three complementary approaches: 1) CLIP-based category-agnostic hazard screening using image-text similarity, 2) Integration of scene-level VLM embeddings into transformer-based trajectory planning on Waymo dataset, 3) Using natural language as explicit behavioral constraints on motion planning with doScenes dataset.
Result: 1) Lightweight hazard screening works robustly for diverse/out-of-distribution hazards; 2) Naive global embedding conditioning doesn’t improve trajectory accuracy; 3) Natural language constraints suppress severe planning failures and improve safety in ambiguous scenarios.
Conclusion: VLMs hold significant promise for autonomous driving safety when used to express semantic risk, intent, and behavioral constraints, but realizing this requires careful engineering design and structured grounding rather than direct feature injection.
Abstract: Vision-language models (VLMs) have recently emerged as powerful representation learning systems that align visual observations with natural language concepts, offering new opportunities for semantic reasoning in safety-critical autonomous driving. This paper investigates how vision-language representations support driving scene safety assessment and decision-making when integrated into perception, prediction, and planning pipelines. We study three complementary system-level use cases. First, we introduce a lightweight, category-agnostic hazard screening approach leveraging CLIP-based image-text similarity to produce a low-latency semantic hazard signal. This enables robust detection of diverse and out-of-distribution road hazards without explicit object detection or visual question answering. Second, we examine the integration of scene-level vision-language embeddings into a transformer-based trajectory planning framework using the Waymo Open Dataset. Our results show that naively conditioning planners on global embeddings does not improve trajectory accuracy, highlighting the importance of representation-task alignment and motivating the development of task-informed extraction methods for safety-critical planning. Third, we investigate natural language as an explicit behavioral constraint on motion planning using the doScenes dataset. In this setting, passenger-style instructions grounded in visual scene elements suppress rare but severe planning failures and improve safety-aligned behavior in ambiguous scenarios. Taken together, these findings demonstrate that vision-language representations hold significant promise for autonomous driving safety when used to express semantic risk, intent, and behavioral constraints. Realizing this potential is fundamentally an engineering problem requiring careful system design and structured grounding rather than direct feature injection.
[278] Process-of-Thought Reasoning for Videos
Jusheng Zhang, Kaitong Cai, Jian Wang, Yongsen Zheng, Kwok-Yan Lam, Keze Wang
Main category: cs.CV
TL;DR: PoT Reasoning for Videos is a framework that structures video understanding into explicit, verifiable reasoning steps with temporal evidence selection, state updates, and constrained answer synthesis.
Details
Motivation: Video understanding requires complex temporal reasoning over long, noisy observations, but current approaches often lack explicit reasoning processes and struggle with temporal grounding and hallucination.Method: Proposes Process-of-Thought (PoT) framework with three interleaved components: temporal evidence selection, step-wise state updates, and constrained answer synthesis. Uses unified representation for PoT traces aligning decisions with temporal segments. Model-agnostic design works with existing vision-language backbones.
Result: Extensive experiments show PoT consistently improves factual correctness and temporal grounding while providing interpretable reasoning traces. Reduces hallucinated explanations and improves robustness to distractors.
Conclusion: PoT Reasoning for Videos provides an effective framework for explicit, verifiable video reasoning that enhances both performance and interpretability in video understanding tasks.
Abstract: Video understanding requires not only recognizing visual content but also performing temporally grounded, multi-step reasoning over long and noisy observations. We propose Process-of-Thought (PoT) Reasoning for Videos, a framework that makes the reasoning process explicit by structuring video inference into a sequence of lightweight, verifiable steps. PoT interleaves (i) temporal evidence selection, (ii) step-wise state updates, and (iii) constrained answer synthesis, enabling the model to progressively refine hypotheses while maintaining traceability to video evidence. The framework is designed to be model-agnostic and can be plugged into existing vision-language backbones, supporting both closed-book reasoning and evidence-augmented reasoning with external tools. We further introduce a unified representation for PoT traces that aligns intermediate decisions with temporal segments, which improves robustness to distractors and reduces hallucinated explanations. Extensive experiments on standard video reasoning tasks demonstrate that PoT consistently improves factual correctness and temporal grounding, while providing interpretable reasoning traces for diagnosis and downstream use.
[279] Semantic-Deviation-Anchored Multi-Branch Fusion for Unsupervised Anomaly Detection and Localization in Unstructured Conveyor-Belt Coal Scenes
Wenping Jin, Yuyang Tang, Li Zhu
Main category: cs.CV
TL;DR: A benchmark and method for unsupervised foreign-object anomaly detection in coal conveyor belt scenes using complementary-cue collaborative perception.
Details
Motivation: Foreign-object detection in coal mining is challenging due to unstructured environments with random coal/gangue piles, complex backgrounds, low contrast, deformation, and occlusion, which weaken assumptions of existing anomaly detection methods designed for structured industrial settings.Method: Proposes a complementary-cue collaborative perception framework that extracts and fuses anomaly evidence from three perspectives: object-level semantic composition modeling, semantic-attribution-based global deviation analysis, and fine-grained texture matching.
Result: Experiments on the CoalAD benchmark show the method outperforms widely used baselines across image-level and pixel-level metrics, with ablation studies validating each component’s contribution.
Conclusion: The proposed framework provides robust anomaly detection and accurate pixel-level localization for challenging coal mining environments, addressing limitations of existing methods in unstructured industrial settings.
Abstract: Reliable foreign-object anomaly detection and pixel-level localization in conveyor-belt coal scenes are essential for safe and intelligent mining operations. This task is particularly challenging due to the highly unstructured environment: coal and gangue are randomly piled, backgrounds are complex and variable, and foreign objects often exhibit low contrast, deformation, occlusion, resulting in coupling with their surroundings. These characteristics weaken the stability and regularity assumptions that many anomaly detection methods rely on in structured industrial settings, leading to notable performance degradation. To support evaluation and comparison in this setting, we construct \textbf{CoalAD}, a benchmark for unsupervised foreign-object anomaly detection with pixel-level localization in coal-stream scenes. We further propose a complementary-cue collaborative perception framework that extracts and fuses complementary anomaly evidence from three perspectives: object-level semantic composition modeling, semantic-attribution-based global deviation analysis, and fine-grained texture matching. The fused outputs provide robust image-level anomaly scoring and accurate pixel-level localization. Experiments on CoalAD demonstrate that our method outperforms widely used baselines across the evaluated image-level and pixel-level metrics, and ablation studies validate the contribution of each component. The code is available at https://github.com/xjpp2016/USAD.
[280] A hybrid Kolmogorov-Arnold network for medical image segmentation
Deep Bhattacharyya, Ali Ayub, A. Ben Hamza
Main category: cs.CV
TL;DR: U-KABS: A hybrid medical image segmentation framework combining U-Net architecture with Kolmogorov-Arnold Networks using Bernstein polynomials and B-splines for enhanced feature representation.
Details
Motivation: Medical image segmentation is challenging due to complexity and variability of medical images, particularly in capturing non-linear relationships within data. Existing methods may not adequately handle these complex patterns.Method: U-KABS integrates U-shaped encoder-decoder architecture with Kolmogorov-Arnold Networks (KANs). It combines convolutional and squeeze-and-excitation stages for channel-wise feature enhancement with KAN Bernstein Spline (KABS) stage using learnable activation functions based on Bernstein polynomials and B-splines.
Result: U-KABS demonstrates superior performance across diverse medical imaging benchmark datasets compared to strong baselines, particularly in segmenting complex anatomical structures.
Conclusion: The hybrid design effectively captures both broad contextual trends and fine-grained patterns critical for medical image segmentation, leveraging global smoothness of Bernstein polynomials and local adaptability of B-splines.
Abstract: Medical image segmentation plays a vital role in diagnosis and treatment planning, but remains challenging due to the inherent complexity and variability of medical images, especially in capturing non-linear relationships within the data. We propose U-KABS, a novel hybrid framework that integrates the expressive power of Kolmogorov-Arnold Networks (KANs) with a U-shaped encoder-decoder architecture to enhance segmentation performance. The U-KABS model combines the convolutional and squeeze-and-excitation stage, which enhances channel-wise feature representations, and the KAN Bernstein Spline (KABS) stage, which employs learnable activation functions based on Bernstein polynomials and B-splines. This hybrid design leverages the global smoothness of Bernstein polynomials and the local adaptability of B-splines, enabling the model to effectively capture both broad contextual trends and fine-grained patterns critical for delineating complex structures in medical images. Skip connections between encoder and decoder layers support effective multi-scale feature fusion and preserve spatial details. Evaluated across diverse medical imaging benchmark datasets, U-KABS demonstrates superior performance compared to strong baselines, particularly in segmenting complex anatomical structures.
[281] All-Optical Segmentation via Diffractive Neural Networks for Autonomous Driving
Yingjie Li, Daniel Robinson, Cunxi Yu
Main category: cs.CV
TL;DR: An all-optical computing framework using diffractive optical neural networks (DONNs) for RGB image segmentation and lane detection in autonomous driving, offering energy-efficient processing at light speed.
Details
Motivation: Traditional deep neural networks for autonomous driving tasks (segmentation and lane detection) require extensive analog-to-digital conversions and large-scale image computations, leading to high energy costs. DONNs offer promising energy efficiency advantages by performing all-optical image processing via light diffraction.Method: Proposes a novel all-optical computing framework using diffractive optical neural networks (DONNs) for RGB image segmentation and lane detection. The system performs all-optical encoding and computing via light diffraction, eliminating analog-to-digital conversion overhead.
Result: Experimental results demonstrate effectiveness of DONN system for image segmentation on CityScapes dataset. Case studies on lane detection using customized indoor track dataset and simulated driving scenarios in CARLA show model’s generalizability under diverse environmental conditions.
Conclusion: DONNs provide an energy-efficient alternative to conventional DNNs for autonomous driving vision tasks by enabling all-optical computing at light speed, reducing energy costs while maintaining performance for segmentation and lane detection.
Abstract: Semantic segmentation and lane detection are crucial tasks in autonomous driving systems. Conventional approaches predominantly rely on deep neural networks (DNNs), which incur high energy costs due to extensive analog-to-digital conversions and large-scale image computations required for low-latency, real-time responses. Diffractive optical neural networks (DONNs) have shown promising advantages over conventional DNNs on digital or optoelectronic computing platforms in energy efficiency. By performing all-optical image processing via light diffraction at the speed of light, DONNs save computation energy costs while reducing the overhead associated with analog-to-digital conversions by all-optical encoding and computing. In this work, we propose a novel all-optical computing framework for RGB image segmentation and lane detection in autonomous driving applications. Our experimental results demonstrate the effectiveness of the DONN system for image segmentation on the CityScapes dataset. Additionally, we conduct case studies on lane detection using a customized indoor track dataset and simulated driving scenarios in CARLA, where we further evaluate the model’s generalizability under diverse environmental conditions.
[282] Rolling Sink: Bridging Limited-Horizon Training and Open-Ended Testing in Autoregressive Video Diffusion
Haodong Li, Shaoteng Liu, Zhe Lin, Manmohan Chandraker
Main category: cs.CV
TL;DR: Training-free method called Rolling Sink that extends autoregressive video diffusion models to ultra-long durations by addressing train-test gap beyond training horizons through systematic cache maintenance analysis.
Details
Motivation: Autoregressive video diffusion models suffer from visual degradation when tested at longer horizons than trained on, creating a train-test gap. Since open-ended testing can extend beyond any finite training window and long-video training is expensive, the authors seek a training-free solution.Method: The paper conducts systematic analysis of AR cache maintenance and proposes Rolling Sink, a training-free method built on Self Forcing. It effectively scales AR video synthesis to ultra-long durations (5-30 minutes) by addressing the gap between limited training horizons and open-ended testing horizons.
Result: Rolling Sink achieves superior long-horizon visual fidelity and temporal consistency compared to state-of-the-art baselines, enabling consistent subjects, stable colors, coherent structures, and smooth motions in ultra-long video generation.
Conclusion: Rolling Sink provides an effective training-free solution to bridge the train-test gap in autoregressive video diffusion models, enabling scalable ultra-long video synthesis without expensive long-video training.
Abstract: Recently, autoregressive (AR) video diffusion models has achieved remarkable performance. However, due to their limited training durations, a train-test gap emerges when testing at longer horizons, leading to rapid visual degradations. Following Self Forcing, which studies the train-test gap within the training duration, this work studies the train-test gap beyond the training duration, i.e., the gap between the limited horizons during training and open-ended horizons during testing. Since open-ended testing can extend beyond any finite training window, and long-video training is computationally expensive, we pursue a training-free solution to bridge this gap. To explore a training-free solution, we conduct a systematic analysis of AR cache maintenance. These insights lead to Rolling Sink. Built on Self Forcing (trained on only 5s clips), Rolling Sink effectively scales the AR video synthesis to ultra-long durations (e.g., 5-30 minutes at 16 FPS) at test time, with consistent subjects, stable colors, coherent structures, and smooth motions. As demonstrated by extensive experiments, Rolling Sink achieves superior long-horizon visual fidelity and temporal consistency compared to SOTA baselines. Project page: https://rolling-sink.github.io/
[283] Uncertainty-Aware Counterfactual Traffic Signal Control with Predictive Safety and Starvation-Avoidance Constraints Using Vision-Based Sensing
Jayawant Bodagala, Balaji Bodagala
Main category: cs.CV
TL;DR: UCATSC is a model-based traffic signal control system that addresses uncertainty in vision-based perception and ensures safety through hard constraints, unlike reinforcement learning methods.
Details
Motivation: Real-world deployment of adaptive traffic signal control is limited due to uncertainty in vision-based perception, implicit safety approaches, and non-interpretable control policies that are mainly validated in simulation.Method: Models traffic signal control as a stochastic decision process with constraints under partial observability, accounting for vision-based perception uncertainty. Uses counterfactual rollouts in belief space to predict and enforce hard safety and starvation prevention constraints.
Result: The system is designed to improve traffic delay and emissions while preventing safety-critical errors and providing interpretable control policy outputs based on explicit models.
Conclusion: UCATSC offers a model-based approach to traffic signal control that addresses key limitations of existing methods by incorporating uncertainty modeling and hard safety constraints.
Abstract: Real-world deployment of adaptive traffic signal control, to date, remains limited due to the uncertainty associated with vision-based perception, implicit safety, and non-interpretable control policies learned and validated mainly in simulation. In this paper, we introduce UCATSC, a model-based traffic signal control system that models traffic signal control at an intersection using a stochastic decision process with constraints and under partial observability, taking into account the uncertainty associated with vision-based perception. Unlike reinforcement learning methods that learn to predict safety using reward shaping, UCATSC predicts and enforces hard constraints related to safety and starvation prevention during counterfactual rollouts in belief space. The system is designed to improve traffic delay and emission while preventing safety-critical errors and providing interpretable control policy outputs based on explicit models.
[284] VideoTemp-o3: Harmonizing Temporal Grounding and Video Understanding in Agentic Thinking-with-Videos
Wenqi Liu, Yunxiao Wang, Shijie Ma, Meng Liu, Qile Su, Tianke Zhang, Haonan Fan, Changyi Liu, Kaiyu Jiang, Jiankang Chen, Kaiyu Tang, Bin Wen, Fan Yang, Tingting Gao, Han Li, Yinwei Wei, Xuemeng Song
Main category: cs.CV
TL;DR: VideoTemp-o3: A unified agentic framework for long-video understanding that jointly models video grounding and question answering with strong localization capabilities and flexible on-demand clipping.
Details
Motivation: Conventional uniform frame sampling fails to capture key visual evidence in long videos, leading to degraded performance and hallucinations. Existing agentic thinking-with-videos methods are inefficient, suffer from weak localization, and follow rigid workflows.Method: Proposes VideoTemp-o3 framework with: 1) Unified masking mechanism in supervised fine-tuning to encourage exploration while preventing noise, 2) Dedicated reinforcement learning rewards to mitigate reward hacking, 3) Pipeline for constructing high-quality long video grounded QA data, and 4) Benchmark for systematic evaluation across video durations.
Result: Experimental results demonstrate remarkable performance on both long video understanding and grounding tasks.
Conclusion: VideoTemp-o3 provides an effective solution for long-video understanding by addressing key limitations of existing methods through joint modeling of video grounding and question answering with flexible localization capabilities.
Abstract: In long-video understanding, conventional uniform frame sampling often fails to capture key visual evidence, leading to degraded performance and increased hallucinations. To address this, recent agentic thinking-with-videos paradigms have emerged, adopting a localize-clip-answer pipeline in which the model actively identifies relevant video segments, performs dense sampling within those clips, and then produces answers. However, existing methods remain inefficient, suffer from weak localization, and adhere to rigid workflows. To solve these issues, we propose VideoTemp-o3, a unified agentic thinking-with-videos framework that jointly models video grounding and question answering. VideoTemp-o3 exhibits strong localization capability, supports on-demand clipping, and can refine inaccurate localizations. Specifically, in the supervised fine-tuning stage, we design a unified masking mechanism that encourages exploration while preventing noise. For reinforcement learning, we introduce dedicated rewards to mitigate reward hacking. Besides, from the data perspective, we develop an effective pipeline to construct high-quality long video grounded QA data, along with a corresponding benchmark for systematic evaluation across various video durations. Experimental results demonstrate that our method achieves remarkable performance on both long video understanding and grounding.
[285] How well are open sourced AI-generated image detection models out-of-the-box: A comprehensive benchmark study
Simiao Ren, Yuchen Zhou, Xingyu Shen, Kidus Zewde, Tommy Duong, George Huang, Hatsanai, Tiangratanakul, Tsang, Ng, En Wei, Jiayu Xue
Main category: cs.CV
TL;DR: Comprehensive zero-shot evaluation of 16 state-of-the-art AI-generated image detection methods across 12 diverse datasets reveals no universal winner, significant performance gaps, and systematic failure patterns, challenging the “one-size-fits-all” detector paradigm.
Details
Motivation: As AI-generated images proliferate, reliable detection methods are critical for combating misinformation. Existing benchmarks predominantly evaluate fine-tuned models, leaving a gap in understanding out-of-the-box performance - the most common deployment scenario for practitioners.Method: First comprehensive zero-shot evaluation of 16 state-of-the-art detection methods (23 pretrained detector variants) across 12 diverse datasets comprising 2.6 million image samples spanning 291 unique generators including modern diffusion models.
Result: Key findings: (1) No universal winner exists with detector rankings showing substantial instability; (2) 37 percentage-point performance gap between best (75.0% mean accuracy) and worst (37.5%) detectors; (3) Training data alignment causes 20-60% performance variance; (4) Modern commercial generators defeat most detectors (18-30% average accuracy); (5) Three systematic failure patterns identified affecting cross-dataset generalization.
Conclusion: Findings challenge the “one-size-fits-all” detector paradigm and provide actionable deployment guidelines. Practitioners must carefully select detectors based on specific threat landscape rather than relying on published benchmark performance.
Abstract: As AI-generated images proliferate across digital platforms, reliable detection methods have become critical for combating misinformation and maintaining content authenticity. While numerous deepfake detection methods have been proposed, existing benchmarks predominantly evaluate fine-tuned models, leaving a critical gap in understanding out-of-the-box performance – the most common deployment scenario for practitioners. We present the first comprehensive zero-shot evaluation of 16 state-of-the-art detection methods, comprising 23 pretrained detector variants (due to multiple released versions of certain detectors), across 12 diverse datasets, comprising 2.6million image samples spanning 291 unique generators including modern diffusion models. Our systematic analysis reveals striking findings: (1)v7) defeat most detectors, achieving only 18–30% average accuracy; and (5)no universal winner exists, with detector rankings exhibiting substantial instability (Spearman$ρ$: 0.01 – 0.87 across dataset pairs); (2)a 37percentage-point performance gap separates the best detector (75.0% mean accuracy) from the worst (37.5%); (3)training data alignment critically impacts generalization, causing up to 20–60% performance variance within architecturally identical detector families; (4)v4, Midjourneymodern commercial generators (FluxDev, Fireflywe identify three systematic failure patterns affecting cross-dataset generalization. Statistical analysis confirms significant performance differences between detectors (Friedman test: $χ^2$=121.01, $p<10^{-16}$, Kendall$W$=0.524). Our findings challenge the ``one-size-fits-all’’ detector paradigm and provide actionable deployment guidelines, demonstrating that practitioners must carefully select detectors based on their specific threat landscape rather than relying on published benchmark performance.
[286] Out of the box age estimation through facial imagery: A Comprehensive Benchmark of Vision-Language Models vs. out-of-the-box Traditional Architectures
Simiao Ren
Main category: cs.CV
TL;DR: VLMs outperform specialized age estimation models in facial age estimation, with zero-shot VLMs achieving significantly lower MAE (5.65 vs 9.88 years) and better age verification accuracy.
Details
Motivation: There's no systematic benchmark comparing modern vision-language models against specialized age estimation architectures, despite age estimation's importance for content moderation, age verification, and deepfake detection.Method: Large-scale cross-paradigm benchmark evaluating 34 models (22 specialized architectures, 12 general-purpose VLMs) across 8 standard datasets totaling 1,100 test images per model, with analysis of MAE, age verification at 18-year threshold, and performance across 14 age groups.
Result: Zero-shot VLMs significantly outperform most specialized models (MAE 5.65 vs 9.88 years), with best VLM (Gemini 3 Flash Preview, MAE 4.32) beating best non-LLM model (MiVOLO, MAE 5.10) by 15%. VLMs achieve 13-25% false adult rates on minors vs 60-100% for non-LLM models.
Conclusion: Task-specific architectures may not be necessary for age estimation; field should redirect toward distilling VLM capabilities into efficient specialized models.
Abstract: Facial age estimation is critical for content moderation, age verification, and deepfake detection, yet no prior benchmark has systematically compared modern vision-language models (VLMs) against specialized age estimation architectures. We present the first large-scale cross-paradigm benchmark, evaluating \textbf{34 models} – 22 specialized architectures with publicly available pretrained weights and 12 general-purpose VLMs – across \textbf{8 standard datasets} (UTKFace, IMDB-WIKI, MORPH, AFAD, CACD, FG-NET, APPA-REAL, AgeDB) totaling 1{,}100 test images per model. Our key finding is striking: \emph{zero-shot VLMs significantly outperform most specialized models}, achieving an average MAE of 5.65 years compared to 9.88 for non-LLM models. The best VLM (Gemini3 Flash Preview, MAE4.32) outperforms the best non-LLM model (MiVOLO, MAE~5.10) by 15%. Only MiVOLO, which uniquely combines face and body features via Vision Transformers, competes with VLMs. We further analyze age verification at the 18-year threshold, revealing that non-LLM models exhibit 60–100% false adult rates on minors while VLMs achieve 13–25%, and demonstrate that coarse age binning (8–9 classes) consistently degrades MAE beyond 13 years. Our stratified analysis across 14 age groups reveals that all models struggle most at extreme ages ($<$5 and 65+). These findings challenge the assumption that task-specific architectures are necessary for age estimation and suggest that the field should redirect toward distilling VLM capabilities into efficient specialized models.
[287] Back to Physics: Operator-Guided Generative Paths for SMS MRI Reconstruction
Zhibo Chen, Yu Guan, Yajuan Huang, Chaoqi Chen, XiangJi, Qiuyun Fan, Dong Liang, Qiegen Liu
Main category: cs.CV
TL;DR: Operator-guided diffusion framework for SMS MRI reconstruction using acquisition operators to model degradation and dual-stream network for slice separation and in-plane completion.
Details
Motivation: Current diffusion-based reconstructions for simultaneous multi-slice (SMS) MRI rely on Gaussian-noise models with additional consistency steps that may mismatch actual SMS acquisition physics, leading to suboptimal reconstruction with slice leakage.Method: Proposes operator-guided framework modeling degradation trajectory using known acquisition operators, with OCDI-Net (operator-conditional dual-stream interaction network) that disentangles target-slice content from inter-slice interference and predicts structured degradations for operator-aligned inversion. Uses two-stage chained inference: SMS slice separation followed by in-plane completion.
Result: Experiments on fastMRI brain data and prospectively acquired in vivo diffusion MRI data show improved fidelity and reduced slice leakage compared to conventional and learning-based SMS reconstructions.
Conclusion: Operator-guided approach better aligns with SMS physics than Gaussian-noise diffusion models, enabling more accurate reconstruction with reduced inter-slice interference through explicit modeling of acquisition operators.
Abstract: Simultaneous multi-slice (SMS) imaging with in-plane undersampling enables highly accelerated MRI but yields a strongly coupled inverse problem with deterministic inter-slice interference and missing k-space data. Most diffusion-based reconstructions are formulated around Gaussian-noise corruption and rely on additional consistency steps to incorporate SMS physics, which can be mismatched to the operator-governed degradations in SMS acquisition. We propose an operator-guided framework that models the degradation trajectory using known acquisition operators and inverts this process via deterministic updates. Within this framework, we introduce an operator-conditional dual-stream interaction network (OCDI-Net) that explicitly disentangles target-slice content from inter-slice interference and predicts structured degradations for operator-aligned inversion, and we instantiate reconstruction as a two-stage chained inference procedure that performs SMS slice separation followed by in-plane completion. Experiments on fastMRI brain data and prospectively acquired in vivo diffusion MRI data demonstrate improved fidelity and reduced slice leakage over conventional and learning-based SMS reconstructions.
[288] Open-Text Aerial Detection: A Unified Framework For Aerial Visual Grounding And Detection
Guoting Wei, Xia Yuan, Yang Zhou, Haizhao Jing, Yu Liu, Xianbiao Qi, Chunxia Zhao, Haokui Zhang, Rong Xiao
Main category: cs.CV
TL;DR: OTA-Det is a unified framework that bridges Open-Vocabulary Aerial Detection (OVAD) and Remote Sensing Visual Grounding (RSVG) for aerial scene understanding, enabling both rich semantic understanding and multi-target detection with real-time performance.
Details
Motivation: Current aerial scene understanding methods have limitations: OVAD only provides coarse category-level semantics, while RSVG is structurally limited to single-target localization. There's a need for a unified approach that supports both rich semantic understanding and multi-target detection simultaneously.Method: Proposes OTA-Det framework with: 1) Task reformulation strategy to unify objectives and supervision mechanisms for joint training across OVAD and RSVG datasets, 2) Dense semantic alignment strategy establishing explicit correspondence at multiple granularities (holistic expressions to individual attributes), 3) Extension of RT-DETR architecture with efficient modules for open-text detection.
Result: Achieves state-of-the-art performance on six benchmarks spanning both OVAD and RSVG tasks while maintaining real-time inference at 34 FPS.
Conclusion: OTA-Det successfully bridges two key aerial scene understanding paradigms, enabling simultaneous rich semantic understanding and multi-target detection with real-time efficiency, representing a significant advancement in aerial vision tasks.
Abstract: Open-Vocabulary Aerial Detection (OVAD) and Remote Sensing Visual Grounding (RSVG) have emerged as two key paradigms for aerial scene understanding. However, each paradigm suffers from inherent limitations when operating in isolation: OVAD is restricted to coarse category-level semantics, while RSVG is structurally limited to single-target localization. These limitations prevent existing methods from simultaneously supporting rich semantic understanding and multi-target detection. To address this, we propose OTA-Det, the first unified framework that bridges both paradigms into a cohesive architecture. Specifically, we introduce a task reformulation strategy that unifies task objectives and supervision mechanisms, enabling joint training across datasets from both paradigms with dense supervision signals. Furthermore, we propose a dense semantic alignment strategy that establishes explicit correspondence at multiple granularities, from holistic expressions to individual attributes, enabling fine-grained semantic understanding. To ensure real-time efficiency, OTA-Det builds upon the RT-DETR architecture, extending it from closed-set detection to open-text detection by introducing several high efficient modules, achieving state-of-the-art performance on six benchmarks spanning both OVAD and RSVG tasks while maintaining real-time inference at 34 FPS.
[289] SPD-Faith Bench: Diagnosing and Improving Faithfulness in Chain-of-Thought for Multimodal Large Language Models
Weijiang Lv, Yaoxuan Feng, Xiaobo Xia, Jiayu Wang, Yan Jing, Wenchao Chen, Bo Chen
Main category: cs.CV
TL;DR: SPD-Faith Bench is a diagnostic benchmark for evaluating reasoning faithfulness in multimodal LLMs, revealing systematic failure modes like perceptual blindness and perception-reasoning dissociation, with proposed SAGE framework for improvement.
Details
Motivation: Current Chain-of-Thought reasoning in MLLMs lacks evaluation of faithfulness beyond response correctness, with reasoning-level unfaithfulness underexplored compared to perceptual hallucinations.Method: Introduces SPD-Faith Bench based on fine-grained image difference reasoning to isolate faithfulness from linguistic priors, then proposes SAGE - a train-free visual evidence-calibrated framework to improve visual routing and align reasoning with perception.
Result: Evaluations reveal two systematic failure modes: perceptual blindness and perception-reasoning dissociation, traced to decaying visual attention and representation shifts in residual stream. SAGE framework shows improvements.
Conclusion: Highlights importance of explicitly evaluating faithfulness beyond response correctness in MLLMs, with benchmark and methods provided for better reasoning trace evaluation.
Abstract: Chain-of-Thought reasoning is widely used to improve the interpretability of multimodal large language models (MLLMs), yet the faithfulness of the generated reasoning traces remains unclear. Prior work has mainly focused on perceptual hallucinations, leaving reasoning level unfaithfulness underexplored. To isolate faithfulness from linguistic priors, we introduce SPD-Faith Bench, a diagnostic benchmark based on fine-grained image difference reasoning that enforces explicit visual comparison. Evaluations on state-of-the-art MLLMs reveal two systematic failure modes, perceptual blindness and perception-reasoning dissociation. We trace these failures to decaying visual attention and representation shifts in the residual stream. Guided by this analysis, we propose SAGE, a train-free visual evidence-calibrated framework that improves visual routing and aligns reasoning with perception. Our results highlight the importance of explicitly evaluating faithfulness beyond response correctness. Our benchmark and codes are available at https://github.com/Johanson-colab/SPD-Faith-Bench.
[290] VFace: A Training-Free Approach for Diffusion-Based Video Face Swapping
Sanoojan Baliah, Yohan Abeysinghe, Rusiru Thushara, Khan Muhammad, Abhinav Dhall, Karthik Nandakumar, Muhammad Haris Khan
Main category: cs.CV
TL;DR: VFace is a training-free, plug-and-play method for high-quality face swapping in videos that integrates with diffusion-based image face swapping approaches, focusing on temporal consistency and visual fidelity.
Details
Motivation: Existing video face swapping methods often suffer from temporal inconsistencies when applied frame-by-frame, requiring additional training or fine-tuning. The authors aim to create a modular solution that enhances temporal coherence without modifying the underlying diffusion models.Method: Three key techniques: 1) Frequency Spectrum Attention Interpolation to preserve identity characteristics, 2) Target Structure Guidance via plug-and-play attention injection for structural alignment, and 3) Flow-Guided Attention Temporal Smoothening for spatiotemporal coherence without model modifications.
Result: Extensive experiments show VFace significantly enhances temporal consistency and visual fidelity compared to frame-wise generation approaches, offering a practical modular solution for video face swapping.
Conclusion: VFace provides an effective training-free, plug-and-play method for high-quality video face swapping that can be seamlessly integrated with existing diffusion-based image face swapping models, addressing temporal inconsistency issues without requiring additional training.
Abstract: We present a training-free, plug-and-play method, namely VFace, for high-quality face swapping in videos. It can be seamlessly integrated with image-based face swapping approaches built on diffusion models. First, we introduce a Frequency Spectrum Attention Interpolation technique to facilitate generation and intact key identity characteristics. Second, we achieve Target Structure Guidance via plug-and-play attention injection to better align the structural features from the target frame to the generation. Third, we present a Flow-Guided Attention Temporal Smoothening mechanism that enforces spatiotemporal coherence without modifying the underlying diffusion model to reduce temporal inconsistencies typically encountered in frame-wise generation. Our method requires no additional training or video-specific fine-tuning. Extensive experiments show that our method significantly enhances temporal consistency and visual fidelity, offering a practical and modular solution for video-based face swapping. Our code is available at https://github.com/Sanoojan/VFace.
[291] Geometry-Aware Rotary Position Embedding for Consistent Video World Model
Chendong Xiang, Jiajun Liu, Jintao Zhang, Xiao Yang, Zhengwei Fang, Shizun Wang, Zijun Wang, Yingtian Zou, Hang Su, Jun Zhu
Main category: cs.CV
TL;DR: ViewRope introduces geometry-aware encoding for video transformers that injects camera-ray directions into attention layers to improve 3D consistency and spatial persistence in predictive world models.
Details
Motivation: Current predictive world models lack spatial persistence - they fail to maintain stable scene structures over long trajectories and hallucinate details when cameras revisit previously observed locations. This geometric drift stems from reliance on screen-space positional embeddings that conflict with projective geometry required for 3D consistency.Method: Introduces ViewRope, a geometry-aware encoding that injects camera-ray directions directly into video transformer self-attention layers. Also proposes Geometry-Aware Frame-Sparse Attention to selectively attend to relevant historical frames using geometric cues. Presents ViewBench diagnostic suite for measuring loop-closure fidelity and geometric drift.
Result: ViewRope substantially improves long-term consistency while reducing computational costs. The method demonstrates better spatial persistence and reduced hallucination when cameras revisit locations.
Conclusion: Geometry-aware encoding through ViewRope provides a model-native inductive bias for retrieving 3D-consistent content across temporal gaps, addressing fundamental limitations in current predictive world models for interactive AI.
Abstract: Predictive world models that simulate future observations under explicit camera control are fundamental to interactive AI. Despite rapid advances, current systems lack spatial persistence: they fail to maintain stable scene structures over long trajectories, frequently hallucinating details when cameras revisit previously observed locations. We identify that this geometric drift stems from reliance on screen-space positional embeddings, which conflict with the projective geometry required for 3D consistency. We introduce \textbf{ViewRope}, a geometry-aware encoding that injects camera-ray directions directly into video transformer self-attention layers. By parameterizing attention with relative ray geometry rather than pixel locality, ViewRope provides a model-native inductive bias for retrieving 3D-consistent content across temporal gaps. We further propose \textbf{Geometry-Aware Frame-Sparse Attention}, which exploits these geometric cues to selectively attend to relevant historical frames, improving efficiency without sacrificing memory consistency. We also present \textbf{ViewBench}, a diagnostic suite measuring loop-closure fidelity and geometric drift. Our results demonstrate that ViewRope substantially improves long-term consistency while reducing computational costs.
[292] Recovering 3D Shapes from Ultra-Fast Motion-Blurred Images
Fei Yu, Shudan Guo, Shiqing Xin, Beibei Wang, Haisen Zhao, Wenzheng Chen
Main category: cs.CV
TL;DR: A novel inverse rendering method for 3D shape recovery from ultra-fast motion-blurred images using a fast barycentric coordinate solver to enable efficient differentiable simulation of high-speed motion.
Details
Motivation: Traditional 3D reconstruction techniques fail with extreme motion-blurred images common in natural and industrial settings (fast-moving sports objects, rotating machinery), creating a need for methods that can handle ultra-fast motion distortions.Method: Proposes an inverse rendering approach with a fast barycentric coordinate solver that reduces computational overhead by 4.57x, enabling efficient photorealistic simulation of high-speed motion. The method is fully differentiable, allowing gradient propagation from rendered images to 3D shape.
Result: Successfully recovers 3D shapes from 2D imagery of objects undergoing extreme translational and rotational motion, enabling efficient and realistic modeling of ultra-fast moving objects in forward simulation.
Conclusion: The method advances vision-based 3D reconstruction by enabling shape recovery from ultra-fast motion-blurred images, overcoming limitations of traditional techniques like Multi-View Stereo.
Abstract: We consider the problem of 3D shape recovery from ultra-fast motion-blurred images. While 3D reconstruction from static images has been extensively studied, recovering geometry from extreme motion-blurred images remains challenging. Such scenarios frequently occur in both natural and industrial settings, such as fast-moving objects in sports (e.g., balls) or rotating machinery, where rapid motion distorts object appearance and makes traditional 3D reconstruction techniques like Multi-View Stereo (MVS) ineffective. In this paper, we propose a novel inverse rendering approach for shape recovery from ultra-fast motion-blurred images. While conventional rendering techniques typically synthesize blur by averaging across multiple frames, we identify a major computational bottleneck in the repeated computation of barycentric weights. To address this, we propose a fast barycentric coordinate solver, which significantly reduces computational overhead and achieves a speedup of up to 4.57x, enabling efficient and photorealistic simulation of high-speed motion. Crucially, our method is fully differentiable, allowing gradients to propagate from rendered images to the underlying 3D shape, thereby facilitating shape recovery through inverse rendering. We validate our approach on two representative motion types: rapid translation and rotation. Experimental results demonstrate that our method enables efficient and realistic modeling of ultra-fast moving objects in the forward simulation. Moreover, it successfully recovers 3D shapes from 2D imagery of objects undergoing extreme translational and rotational motion, advancing the boundaries of vision-based 3D reconstruction. Project page: https://maxmilite.github.io/rec-from-ultrafast-blur/
[293] Thinking in Structures: Evaluating Spatial Intelligence through Reasoning on Constrained Manifolds
Chen Yang, Guanxin Lin, Youquan He, Peiyao Chen, Guanghe Liu, Yufan Mo, Zhouyuan Xu, Linhao Wang, Guohui Zhang, Zihang Zhang, Shenxiang Zeng, Chen Wang, Jiansheng Fan
Main category: cs.CV
TL;DR: SSI-Bench is a spatial reasoning benchmark for VLMs that tests 3D geometric and topological reasoning on constrained real-world structures, revealing large performance gaps between models and humans.
Details
Motivation: Existing VLM benchmarks often allow models to exploit 2D shortcuts rather than requiring genuine 3D spatial reasoning. The authors aim to create a more rigorous benchmark that evaluates true spatial intelligence on constrained manifolds where geometric, topological, and physical constraints govern feasible configurations.Method: Created SSI-Bench through a human-centered pipeline: 10 researchers spent 400+ hours curating images of complex real-world 3D structures, annotating structural components, and designing 1,000 ranking questions that minimize pixel-level cues. Questions test geometric and topological reasoning requiring operations like mental rotation, cross-sectional inference, occlusion reasoning, and force-path reasoning.
Result: Evaluation of 31 VLMs shows large performance gaps: best open-source model achieves 22.2% accuracy, best closed-source model reaches 33.6%, while humans score 91.6%. Encouraging models to “think” yields only marginal gains. Error analysis reveals failures in structural grounding and constraint-consistent 3D reasoning.
Conclusion: SSI-Bench reveals significant limitations in current VLMs’ spatial reasoning capabilities, particularly in handling constrained 3D structures. The benchmark provides a rigorous testbed for advancing spatial intelligence in vision-language models.
Abstract: Spatial intelligence is crucial for vision–language models (VLMs) in the physical world, yet many benchmarks evaluate largely unconstrained scenes where models can exploit 2D shortcuts. We introduce SSI-Bench, a VQA benchmark for spatial reasoning on constrained manifolds, built from complex real-world 3D structures whose feasible configurations are tightly governed by geometric, topological, and physical constraints. SSI-Bench contains 1,000 ranking questions spanning geometric and topological reasoning and requiring a diverse repertoire of compositional spatial operations, such as mental rotation, cross-sectional inference, occlusion reasoning, and force-path reasoning. It is created via a fully human-centered pipeline: ten researchers spent over 400 hours curating images, annotating structural components, and designing questions to minimize pixel-level cues. Evaluating 31 widely used VLMs reveals a large gap to humans: the best open-source model achieves 22.2% accuracy and the strongest closed-source model reaches 33.6%, while humans score 91.6%. Encouraging models to think yields only marginal gains, and error analysis points to failures in structural grounding and constraint-consistent 3D reasoning. Project page: https://ssi-bench.github.io.
[294] WristMIR: Coarse-to-Fine Region-Aware Retrieval of Pediatric Wrist Radiographs with Radiology Report-Driven Learning
Mert Sonmezer, Serge Vasylechko, Duygu Atasoy, Seyda Ertekin, Sila Kurugol
Main category: cs.CV
TL;DR: WristMIR: A region-aware pediatric wrist radiograph retrieval framework using dense radiology reports and bone-specific localization for fine-grained medical image retrieval without manual annotations.
Details
Motivation: Retrieving wrist radiographs with analogous fracture patterns is challenging due to subtle, localized clinical cues often obscured by overlapping anatomy or variable imaging views. Progress is limited by scarcity of large, well-annotated datasets for case-based medical image retrieval.Method: Uses MedGemma-based structured report mining to generate global and region-level captions, processes wrist images with bone-specific crops (distal radius, distal ulna, ulnar styloid), jointly trains global and local contrastive encoders, and performs two-stage retrieval: coarse global matching followed by region-conditioned reranking.
Result: Improves image-to-text Recall@5 from 0.82% to 9.35%, yields stronger fracture classification (AUROC 0.949, AUPRC 0.953), improves retrieval-based fracture diagnosis (mean F1 from 0.568 to 0.753), and radiologists rate retrieved cases as more clinically relevant (mean scores from 3.36 to 4.35).
Conclusion: Anatomically guided retrieval has potential to enhance diagnostic reasoning and support clinical decision-making in pediatric musculoskeletal imaging, demonstrating the value of region-aware approaches for medical image retrieval.
Abstract: Retrieving wrist radiographs with analogous fracture patterns is challenging because clinically important cues are subtle, highly localized and often obscured by overlapping anatomy or variable imaging views. Progress is further limited by the scarcity of large, well-annotated datasets for case-based medical image retrieval. We introduce WristMIR, a region-aware pediatric wrist radiograph retrieval framework that leverages dense radiology reports and bone-specific localization to learn fine-grained, clinically meaningful image representations without any manual image-level annotations. Using MedGemma-based structured report mining to generate both global and region-level captions, together with pre-processed wrist images and bone-specific crops of the distal radius, distal ulna, and ulnar styloid, WristMIR jointly trains global and local contrastive encoders and performs a two-stage retrieval process: (1) coarse global matching to identify candidate exams, followed by (2) region-conditioned reranking aligned to a predefined anatomical bone region. WristMIR improves retrieval performance over strong vision-language baselines, raising image-to-text Recall@5 from 0.82% to 9.35%. Its embeddings also yield stronger fracture classification (AUROC 0.949, AUPRC 0.953). In region-aware evaluation, the two-stage design markedly improves retrieval-based fracture diagnosis, increasing mean $F_1$ from 0.568 to 0.753, and radiologists rate its retrieved cases as more clinically relevant, with mean scores rising from 3.36 to 4.35. These findings highlight the potential of anatomically guided retrieval to enhance diagnostic reasoning and support clinical decision-making in pediatric musculoskeletal imaging. The source code is publicly available at https://github.com/quin-med-harvard-edu/WristMIR.
[295] Scalable Adaptation of 3D Geometric Foundation Models via Weak Supervision from Internet Video
Zihui Gao, Ke Liu, Donny Y. Chen, Duochao Shi, Guosheng Lin, Hao Chen, Chunhua Shen
Main category: cs.CV
TL;DR: SAGE: A framework for scalable adaptation of geometric foundation models using raw Internet videos through hierarchical mining, sparse geometric anchoring, and dense differentiable consistency.
Details
Motivation: Geometric foundation models are limited by scarce 3D annotations. Internet videos offer unlimited raw data but lack ground-truth geometry and contain observational noise, making them challenging to use for geometric learning.Method: SAGE uses hierarchical mining to transform videos into training trajectories with hybrid supervision: (1) informative trajectory selection, (2) sparse geometric anchoring via SfM point clouds for global structure, and (3) dense differentiable consistency via 3D Gaussian rendering for multi-view constraints. Includes regularization to prevent catastrophic forgetting.
Result: Significantly enhances zero-shot generalization, reducing Chamfer Distance by 20-42% on unseen benchmarks (7Scenes, TUM-RGBD, Matterport3D) compared to state-of-the-art baselines.
Conclusion: SAGE pioneers adaptation of geometric foundation models via Internet video, establishing a scalable paradigm for general-purpose 3D learning.
Abstract: Geometric foundation models show promise in 3D reconstruction, yet their progress is severely constrained by the scarcity of diverse, large-scale 3D annotations. While Internet videos offer virtually unlimited raw data, utilizing them as a scaling source for geometric learning is challenging due to the absence of ground-truth geometry and the presence of observational noise. To address this, we propose SAGE, a framework for Scalable Adaptation of GEometric foundation models from raw video streams. SAGE leverages a hierarchical mining pipeline to transform videos into training trajectories and hybrid supervision: (1) Informative training trajectory selection; (2) Sparse Geometric Anchoring via SfM point clouds for global structural guidance; and (3) Dense Differentiable Consistency via 3D Gaussian rendering for multi-view constraints. To prevent catastrophic forgetting, we introduce a regularization strategy using anchor data. Extensive experiments show that SAGE significantly enhances zero-shot generalization, reducing Chamfer Distance by 20-42% on unseen benchmarks (7Scenes, TUM-RGBD, Matterport3D) compared to state-of-the-art baselines. To our knowledge, SAGE pioneers the adaptation of geometric foundation models via Internet video, establishing a scalable paradigm for general-purpose 3D learning.
[296] Rethinking Practical and Efficient Quantization Calibration for Vision-Language Models
Zhenhao Shang, Haizhao Jing, Guoting Wei, Haokui Zhang, Rong Xiao, Jianqing Gao, Peng Wang
Main category: cs.CV
TL;DR: TLQ: Token-level Importance-aware Layer-wise Quantization framework for vision-language models that addresses activation distribution differences between visual/text tokens through gradient-guided importance integration and distributed multi-GPU calibration.
Details
Motivation: Post-training quantization (PTQ) for vision-language models faces challenges due to substantial differences between visual and text tokens in activation distributions and quantization sensitivity, making effective calibration difficult.Method: Proposes TLQ framework with: 1) gradient-guided token-level importance integration mechanism for quantization error, 2) token-level calibration set construction for fine-grained calibration, 3) multi-GPU quantization-exposed layer-wise calibration scheme that distributes workload across RTX3090 GPUs.
Result: Evaluated across two models, three model scales, and two quantization settings, consistently achieving performance improvements across all settings, demonstrating strong quantization stability.
Conclusion: TLQ provides an effective PTQ solution for VLMs that addresses token distribution differences through fine-grained importance-aware calibration and practical distributed implementation.
Abstract: Post-training quantization (PTQ) is a primary approach for deploying large language models without fine-tuning, and the quantized performance is often strongly affected by the calibration in PTQ. By contrast, in vision-language models (VLMs), substantial differences between visual and text tokens in their activation distributions and sensitivities to quantization error pose significant challenges for effective calibration during PTQ. In this work, we rethink what PTQ calibration should align with in VLMs and propose the Token-level Importance-aware Layer-wise Quantization framework (TLQ). Guided by gradient information, we design a token-level importance integration mechanism for quantization error, and use it to construct a token-level calibration set, enabling a more fine-grained calibration strategy. Furthermore, TLQ introduces a multi-GPU, quantization-exposed layer-wise calibration scheme. This scheme keeps the layer-wise calibration procedure consistent with the true quantized inference path and distributes the complex layer-wise calibration workload across multiple RTX3090 GPUs, thereby reducing reliance on the large memory of A100 GPUs. TLQ is evaluated across two models, three model scales, and two quantization settings, consistently achieving performance improvements across all settings, indicating its strong quantization stability. The code will be released publicly.
[297] Which private attributes do VLMs agree on and predict well?
Olena Hrynenko, Darya Baranouskaya, Alina Elena Baia, Andrea Cavallaro
Main category: cs.CV
TL;DR: VLMs evaluated for zero-shot privacy attribute recognition in images, showing they predict privacy attributes more often than humans but can complement human annotations in high-agreement cases.
Details
Motivation: To evaluate the capability of open-source Visual Language Models (VLMs) for zero-shot detection of privacy-related attributes in images, and to understand how VLM annotations compare with human annotations for privacy attribute recognition.Method: Conducted zero-shot evaluation of open-source VLMs for privacy attribute recognition, identified attributes with strong inter-annotator agreement among VLMs, and analyzed disagreement cases between human and VLM annotations.
Result: VLMs tend to predict the presence of privacy attributes more frequently than human annotators. In cases of high inter-annotator agreement between VLMs, they can complement human annotation by identifying attributes that human annotators overlook.
Conclusion: VLMs have potential to support privacy annotations in large-scale image datasets, particularly when they show high inter-annotator agreement, as they can identify privacy attributes that human annotators might miss.
Abstract: Visual Language Models (VLMs) are often used for zero-shot detection of visual attributes in the image. We present a zero-shot evaluation of open-source VLMs for privacy-related attribute recognition. We identify the attributes for which VLMs exhibit strong inter-annotator agreement, and discuss the disagreement cases of human and VLM annotations. Our results show that when evaluated against human annotations, VLMs tend to predict the presence of privacy attributes more often than human annotators. In addition to this, we find that in cases of high inter-annotator agreement between VLMs, they can complement human annotation by identifying attributes overlooked by human annotators. This highlights the potential of VLMs to support privacy annotations in large-scale image datasets.
[298] Integrating Specialized and Generic Agent Motion Prediction with Dynamic Occupancy Grid Maps
Rabbia Asghar, Lukas Rummelhard, Wenqian Liu, Anne Spalanzani, Christian Laugier
Main category: cs.CV
TL;DR: A unified framework for simultaneous prediction of future occupancy grids, vehicle grids, and scene flow grids using Dynamic Occupancy Grid Maps with interdependent loss functions for robust motion forecasting.
Details
Motivation: Existing prediction methods have limitations: agent-agnostic models struggle with behavioral complexities of dynamic actors, while agent-specific approaches fail to generalize to poorly perceived or unrecognized agents. Combining both paradigms enables more robust and safer motion forecasting.Method: Proposes a unified framework using Dynamic Occupancy Grid Maps within a streamlined temporal decoding pipeline. Uses a lightweight spatiotemporal backbone with a tailored interdependent loss function that captures inter-grid dependencies and enables diverse future predictions. The loss function uses occupancy state information to enforce flow-guided transitions, acting as a regularizer for occupancy evolution while accounting for obstacles and occlusions.
Result: Evaluations on real-world nuScenes and Woven Planet datasets demonstrate superior prediction performances for dynamic vehicles and generic dynamic scene elements compared to baseline methods.
Conclusion: The proposed unified framework successfully combines agent-agnostic and agent-specific prediction approaches, enabling robust prediction of both specific vehicle behaviors and other dynamic entities within complex driving scenes.
Abstract: Accurate prediction of driving scene is a challenging task due to uncertainty in sensor data, the complex behaviors of agents, and the possibility of multiple feasible futures. Existing prediction methods using occupancy grid maps primarily focus on agent-agnostic scene predictions, while agent-specific predictions provide specialized behavior insights with the help of semantic information. However, both paradigms face distinct limitations: agent-agnostic models struggle to capture the behavioral complexities of dynamic actors, whereas agent-specific approaches fail to generalize to poorly perceived or unrecognized agents; combining both enables robust and safer motion forecasting. To address this, we propose a unified framework by leveraging Dynamic Occupancy Grid Maps within a streamlined temporal decoding pipeline to simultaneously predict future occupancy state grids, vehicle grids, and scene flow grids. Relying on a lightweight spatiotemporal backbone, our approach is centered on a tailored, interdependent loss function that captures inter-grid dependencies and enables diverse future predictions. By using occupancy state information to enforce flow-guided transitions, the loss function acts as a regularizer that directs occupancy evolution while accounting for obstacles and occlusions. Consequently, the model not only predicts the specific behaviors of vehicle agents, but also identifies other dynamic entities and anticipates their evolution within the complex scene. Evaluations on real-world nuScenes and Woven Planet datasets demonstrate superior prediction performances for dynamic vehicles and generic dynamic scene elements compared to baseline methods.
[299] One-Shot Crowd Counting With Density Guidance For Scene Adaptaion
Jiwei Chen, Qi Wang, Junyu Gao, Jing Zhang, Dingyi Li, Jing-Jia Luo
Main category: cs.CV
TL;DR: A few-shot learning approach for crowd counting that adapts to unseen surveillance scenes using local and global density characteristics
Details
Motivation: Existing crowd counting models have limited generalization to unseen surveillance scenes due to significant variations between camera locations and scenesMethod: Proposes multiple local density learners to capture different density distributions via prototypes, encodes local density similarity matrices, and extracts global density features from support images to guide adaptation
Result: Outperforms recent state-of-the-art methods on three surveillance datasets for few-shot crowd counting
Conclusion: The approach effectively adapts crowd counting models to unseen surveillance scenes by leveraging both local and global density characteristics through few-shot learning
Abstract: Crowd scenes captured by cameras at different locations vary greatly, and existing crowd models have limited generalization for unseen surveillance scenes. To improve the generalization of the model, we regard different surveillance scenes as different category scenes, and introduce few-shot learning to make the model adapt to the unseen surveillance scene that belongs to the given exemplar category scene. To this end, we propose to leverage local and global density characteristics to guide the model of crowd counting for unseen surveillance scenes. Specifically, to enable the model to adapt to the varying density variations in the target scene, we propose the multiple local density learner to learn multi prototypes which represent different density distributions in the support scene. Subsequently, these multiple local density similarity matrixes are encoded. And they are utilized to guide the model in a local way. To further adapt to the global density in the target scene, the global density features are extracted from the support image, then it is used to guide the model in a global way. Experiments on three surveillance datasets shows that proposed method can adapt to the unseen surveillance scene and outperform recent state-of-the-art methods in the few-shot crowd counting.
[300] D-ORCA: Dialogue-Centric Optimization for Robust Audio-Visual Captioning
Changli Tang, Tianyi Wang, Fengyun Rao, Jing Lyu, Chao Zhang
Main category: cs.CV
TL;DR: D-ORCA is a dialogue-centric omni-modal LLM for robust audio-visual captioning, trained on DVD dataset with novel reinforcement learning rewards for speaker attribution, speech content accuracy, and temporal alignment.
Details
Motivation: Spoken dialogue is crucial for video understanding, but current models lack accurate speaker identification, speech recognition, and temporal grounding in multi-party dialogue videos.Method: Developed D-ORCA (dialogue-centric omni-modal LLM) trained on DVD dataset (40K videos). Used group relative policy optimization with three novel reward functions: speaker attribution accuracy, global speech content accuracy, and sentence-level temporal boundary alignment.
Result: D-ORCA substantially outperforms existing open-source models in speaker identification, speech recognition, and temporal grounding. Despite only 8B parameters, achieves performance competitive with Qwen3-Omni on general audio-visual understanding benchmarks.
Conclusion: D-ORCA advances audio-visual captioning for dialogue videos through novel reinforcement learning objectives and large-scale bilingual dataset, enabling accurate speaker attribution and temporal alignment.
Abstract: Spoken dialogue is a primary source of information in videos; therefore, accurately identifying who spoke what and when is essential for deep video understanding. We introduce D-ORCA, a \textbf{d}ialogue-centric \textbf{o}mni-modal large language model optimized for \textbf{r}obust audio-visual \textbf{ca}ptioning. We further curate DVD, a large-scale, high-quality bilingual dataset comprising nearly 40,000 multi-party dialogue videos for training and 2000 videos for evaluation in English and Mandarin, addressing a critical gap in the open-source ecosystem. To ensure fine-grained captioning accuracy, we adopt group relative policy optimization with three novel reward functions that assess speaker attribution accuracy, global speech content accuracy, and sentence-level temporal boundary alignment. These rewards are derived from evaluation metrics widely used in speech processing and, to our knowledge, are applied for the first time as reinforcement learning objectives for audio-visual captioning. Extensive experiments demonstrate that D-ORCA substantially outperforms existing open-source models in speaker identification, speech recognition, and temporal grounding. Notably, despite having only 8 billion parameters, D-ORCA achieves performance competitive with Qwen3-Omni across several general-purpose audio-visual understanding benchmarks. Demos are available at \href{https://d-orca-llm.github.io/}{https://d-orca-llm.github.io/}. Our code, data, and checkpoints will be available at \href{https://github.com/WeChatCV/D-ORCA/}{https://github.com/WeChatCV/D-ORCA/}.
[301] EasyTune: Efficient Step-Aware Fine-Tuning for Diffusion-Based Motion Generation
Xiaofeng Tan, Wanjiang Weng, Haodong Lei, Hongsong Wang
Main category: cs.CV
TL;DR: EasyTune improves diffusion model alignment by fine-tuning individual denoising steps rather than entire trajectories, addressing inefficiency and memory issues in preference alignment for motion generation.
Details
Motivation: Current motion generative models using differentiable rewards for alignment suffer from inefficient optimization, coarse-grained tuning, and high memory consumption due to recursive dependencies between denoising steps.Method: Proposes EasyTune which fine-tunes diffusion models at each denoising step individually, decoupling recursive dependencies. Also introduces Self-refinement Preference Learning (SPL) to dynamically identify preference pairs when training data is scarce.
Result: Outperforms DRaFT-50 by 8.2% in alignment (MM-Dist) improvement while requiring only 31.16% of its memory overhead and achieving 7.3x training speedup.
Conclusion: EasyTune provides an efficient, memory-friendly approach to aligning diffusion models with downstream objectives, particularly valuable for motion generation where preference data is limited.
Abstract: In recent years, motion generative models have undergone significant advancement, yet pose challenges in aligning with downstream objectives. Recent studies have shown that using differentiable rewards to directly align the preference of diffusion models yields promising results. However, these methods suffer from (1) inefficient and coarse-grained optimization with (2) high memory consumption. In this work, we first theoretically and empirically identify the key reason of these limitations: the recursive dependence between different steps in the denoising trajectory. Inspired by this insight, we propose EasyTune, which fine-tunes diffusion at each denoising step rather than over the entire trajectory. This decouples the recursive dependence, allowing us to perform (1) a dense and fine-grained, and (2) memory-efficient optimization. Furthermore, the scarcity of preference motion pairs restricts the availability of motion reward model training. To this end, we further introduce a Self-refinement Preference Learning (SPL) mechanism that dynamically identifies preference pairs and conducts preference learning. Extensive experiments demonstrate that EasyTune outperforms DRaFT-50 by 8.2% in alignment (MM-Dist) improvement while requiring only 31.16% of its additional memory overhead and achieving a 7.3x training speedup. The project page is available at this link {https://xiaofeng-tan.github.io/projects/EasyTune/index.html}.
[302] FSP-Diff: Full-Spectrum Prior-Enhanced DualDomain Latent Diffusion for Ultra-Low-Dose Spectral CT Reconstruction
Peng Peng, Xinrui Zhang, Junlin Wang, Lei Li, Shaoyu Wang, Qiegen Liu
Main category: cs.CV
TL;DR: FSP-Diff: A full-spectrum prior-enhanced dual-domain latent diffusion framework for ultra-low-dose spectral CT reconstruction that integrates complementary features, full-spectrum priors, and efficient latent diffusion synthesis.
Details
Motivation: Ultra-low-dose spectral CT suffers from severely degraded signal-to-noise ratio in energy-specific projections, causing artifacts and loss of structural details. Existing methods struggle to balance noise suppression with detail preservation in such challenging conditions.Method: Three core strategies: 1) Complementary feature construction integrating direct image reconstructions with projection-domain denoised results, 2) Full-spectrum prior integration fusing multi-energy projections into high-SNR reference, 3) Efficient latent diffusion synthesis embedding multi-path features into compact latent space for accelerated reconstruction.
Result: Extensive experiments on simulated and real-world datasets show FSP-Diff significantly outperforms state-of-the-art methods in both image quality and computational efficiency.
Conclusion: FSP-Diff demonstrates potential for clinically viable ultra-low-dose spectral CT imaging by effectively balancing detail fidelity and noise suppression through its integrated framework.
Abstract: Spectral computed tomography (CT) with photon-counting detectors holds immense potential for material discrimination and tissue characterization. However, under ultra-low-dose conditions, the sharply degraded signal-to-noise ratio (SNR) in energy-specific projections poses a significant challenge, leading to severe artifacts and loss of structural details in reconstructed images. To address this, we propose FSP-Diff, a full-spectrum prior-enhanced dual-domain latent diffusion framework for ultra-low-dose spectral CT reconstruction. Our framework integrates three core strategies: 1) Complementary Feature Construction: We integrate direct image reconstructions with projection-domain denoised results. While the former preserves latent textural nuances amidst heavy noise, the latter provides a stable structural scaffold to balance detail fidelity and noise suppression. 2) Full-Spectrum Prior Integration: By fusing multi-energy projections into a high-SNR full-spectrum image, we establish a unified structural reference that guides the reconstruction across all energy bins. 3) Efficient Latent Diffusion Synthesis: To alleviate the high computational burden of high-dimensional spectral data, multi-path features are embedded into a compact latent space. This allows the diffusion process to facilitate interactive feature fusion in a lower-dimensional manifold, achieving accelerated reconstruction while maintaining fine-grained detail restoration. Extensive experiments on simulated and real-world datasets demonstrate that FSP-Diff significantly outperforms state-of-the-art methods in both image quality and computational efficiency, underscoring its potential for clinically viable ultra-low-dose spectral CT imaging.
[303] Continuity-driven Synergistic Diffusion with Neural Priors for Ultra-Sparse-View CBCT Reconstruction
Junlin Wang, Jiancheng Fang, Peng Peng, Shaoyu Wang, Qiegen Liu
Main category: cs.CV
TL;DR: CSDN framework uses neural priors and synergistic diffusion for ultra-sparse-view CBCT reconstruction, addressing radiation-dose vs image-quality trade-off by restoring angular continuity and inter-slice consistency.
Details
Motivation: Clinical CBCT faces radiation exposure vs image quality trade-off; ultra-sparse angular sampling reduces dose but causes severe undersampling artifacts and inter-slice inconsistencies, compromising diagnostic reliability. Existing methods struggle to balance angular continuity with spatial detail fidelity.Method: Proposes Continuity-driven Synergistic Diffusion with Neural priors (CSDN): 1) Neural priors encode continuous 3D attenuation representation to synthesize dense projections from sparse measurements; 2) Synergistic diffusion with two collaborative paths: Sinogram Refinement Diffusion (Sino-RD) for angular continuity and Digital Radiography Refinement Diffusion (DR-RD) for inter-slice consistency; 3) Dual-Projection Reconstruction Fusion (DPRF) module adaptively fuses outputs for coherent volumetric reconstruction.
Result: Extensive experiments show CSDN effectively suppresses artifacts and recovers fine textures under ultra-sparse-view conditions, outperforming existing state-of-the-art techniques.
Conclusion: CSDN framework successfully addresses ultra-sparse-view CBCT reconstruction challenges by combining neural priors with synergistic diffusion, achieving superior artifact suppression and texture recovery compared to existing methods.
Abstract: The clinical application of cone-beam computed tomography (CBCT) is constrained by the inherent trade-off between radiation exposure and image quality. Ultra-sparse angular sampling, employed to reduce dose, introduces severe undersampling artifacts and inter-slice inconsistencies, compromising diagnostic reliability. Existing reconstruction methods often struggle to balance angular continuity with spatial detail fidelity. To address these challenges, we propose a Continuity-driven Synergistic Diffusion with Neural priors (CSDN) for ultra-sparse-view CBCT reconstruction. Neural priors are introduced as a structural foundation to encode a continuous threedimensional attenuation representation, enabling the synthesis of physically consistent dense projections from ultra-sparse measurements. Building upon this neural-prior-based initialization, a synergistic diffusion strategy is developed, consisting of two collaborative refinement paths: a Sinogram Refinement Diffusion (Sino-RD) process that restores angular continuity and a Digital Radiography Refinement Diffusion (DR-RD) process that enforces inter-slice consistency from the projection image perspective. The outputs of the two diffusion paths are adaptively fused by the Dual-Projection Reconstruction Fusion (DPRF) module to achieve coherent volumetric reconstruction. Extensive experiments demonstrate that the proposed CSDN effectively suppresses artifacts and recovers fine textures under ultra-sparse-view conditions, outperforming existing state-of-the-art techniques.
[304] Deepfake Synthesis vs. Detection: An Uneven Contest
Md. Tarek Hasan, Sanjay Saha, Shaojing Fan, Swakkhar Shatabda, Terence Sim
Main category: cs.CV
TL;DR: Comprehensive empirical analysis shows state-of-the-art deepfake detection models perform poorly against modern synthesis techniques like diffusion models and NeRF, with humans also struggling against high-quality deepfakes.
Details
Motivation: The rapid advancement of deepfake technology using diffusion models, NeRF, and improved GANs has created highly realistic synthetic media, raising concerns about detection capabilities. There's a need to assess whether current detection methods can keep pace with evolving generation techniques.Method: Conducted comprehensive empirical analysis of state-of-the-art deepfake detection techniques, including human evaluation experiments against cutting-edge synthesis methods. Used extensive experimentation to compare detection models with modern generation technologies.
Result: Many state-of-the-art detection models exhibit markedly poor performance when challenged with deepfakes produced by modern synthesis techniques. Human participants also performed poorly against the best quality deepfakes, revealing a significant gap between detection capabilities and generation sophistication.
Conclusion: There’s an urgent need for continued refinement of detection models to keep pace with evolving deepfake generation technologies. The research emphasizes the critical gap between current detection methodologies and new generation techniques, calling for intensified research efforts in this area.
Abstract: The rapid advancement of deepfake technology has significantly elevated the realism and accessibility of synthetic media. Emerging techniques, such as diffusion-based models and Neural Radiance Fields (NeRF), alongside enhancements in traditional Generative Adversarial Networks (GANs), have contributed to the sophisticated generation of deepfake videos. Concurrently, deepfake detection methods have seen notable progress, driven by innovations in Transformer architectures, contrastive learning, and other machine learning approaches. In this study, we conduct a comprehensive empirical analysis of state-of-the-art deepfake detection techniques, including human evaluation experiments against cutting-edge synthesis methods. Our findings highlight a concerning trend: many state-of-the-art detection models exhibit markedly poor performance when challenged with deepfakes produced by modern synthesis techniques, including poor performance by human participants against the best quality deepfakes. Through extensive experimentation, we provide evidence that underscores the urgent need for continued refinement of detection models to keep pace with the evolving capabilities of deepfake generation technologies. This research emphasizes the critical gap between current detection methodologies and the sophistication of new generation techniques, calling for intensified efforts in this crucial area of study.
[305] MCIE: Multimodal LLM-Driven Complex Instruction Image Editing with Spatial Guidance
Xuehai Bai, Xiaoling Gu, Akide Liu, Hangjie Yuan, YiFan Zhang, Jack Ma
Main category: cs.CV
TL;DR: MCIE-E1: A multimodal LLM-driven complex instruction image editing method with spatial-aware and background-consistent attention modules, trained on curated data and evaluated on new benchmark CIE-Bench.
Details
Motivation: Existing instruction-based image editing methods are limited to simple operations, hindering real-world applications requiring complex and compositional instructions. Key challenges include insufficient instruction compliance and background inconsistency.Method: Proposes MCIE-E1 with two key modules: spatial-aware cross-attention (aligns semantic instructions with spatial regions using spatial guidance during denoising) and background-consistent cross-attention (preserves features in unedited regions). Uses a dedicated data pipeline combining fine-grained automatic filtering via MLLM with human validation to address dataset scarcity.
Result: Experimental results on CIE-Bench show MCIE-E1 consistently outperforms previous SOTA methods in both quantitative and qualitative assessments, achieving 23.96% improvement in instruction compliance.
Conclusion: MCIE-E1 addresses limitations in complex instruction-based image editing through novel architectural modules, curated data pipeline, and comprehensive evaluation benchmark, demonstrating significant improvements in instruction compliance and background consistency.
Abstract: Recent advances in instruction-based image editing have shown remarkable progress. However, existing methods remain limited to relatively simple editing operations, hindering real-world applications that require complex and compositional instructions. In this work, we address these limitations from the perspectives of architectural design, data, and evaluation protocols. Specifically, we identify two key challenges in current models: insufficient instruction compliance and background inconsistency. To this end, we propose MCIE-E1, a Multimodal Large Language Model-Driven Complex Instruction Image Editing method that integrates two key modules: a spatial-aware cross-attention module and a background-consistent cross-attention module. The former enhances instruction-following capability by explicitly aligning semantic instructions with spatial regions through spatial guidance during the denoising process, while the latter preserves features in unedited regions to maintain background consistency. To enable effective training, we construct a dedicated data pipeline to mitigate the scarcity of complex instruction-based image editing datasets, combining fine-grained automatic filtering via a powerful MLLM with rigorous human validation. Finally, to comprehensively evaluate complex instruction-based image editing, we introduce CIE-Bench, a new benchmark with two new evaluation metrics. Experimental results on CIE-Bench demonstrate that MCIE-E1 consistently outperforms previous state-of-the-art methods in both quantitative and qualitative assessments, achieving a 23.96% improvement in instruction compliance.
[306] FlashVID: Efficient Video Large Language Models via Training-free Tree-based Spatiotemporal Token Merging
Ziyang Fan, Keyu Chen, Ruilong Xing, Yulin Li, Li Jiang, Zhuotao Tian
Main category: cs.CV
TL;DR: FlashVID is a training-free inference acceleration framework for Video LLMs that reduces computational costs by compressing spatiotemporal redundancy through attention-based token selection and tree-based token merging.
Details
Motivation: Current Video LLMs process high volumes of visual tokens inefficiently, and existing acceleration methods compress spatial and temporal redundancy independently without considering spatiotemporal relationships, leading to suboptimal compression.Method: Uses Attention and Diversity-based Token Selection (ADTS) to select representative tokens for basic video representation, then applies Tree-based Spatiotemporal Token Merging (TSTM) for fine-grained spatiotemporal redundancy elimination.
Result: Retaining only 10% of visual tokens preserves 99.1% of LLaVA-OneVision’s performance. Enables 10x increase in video frame input to Qwen2.5-VL with 8.6% relative improvement within same computational budget.
Conclusion: FlashVID provides effective training-free acceleration for VLLMs by better exploiting spatiotemporal relationships, enabling longer video processing with minimal performance loss.
Abstract: Although Video Large Language Models (VLLMs) have shown remarkable capabilities in video understanding, they are required to process high volumes of visual tokens, causing significant computational inefficiency. Existing VLLMs acceleration frameworks usually compress spatial and temporal redundancy independently, which overlooks the spatiotemporal relationships, thereby leading to suboptimal spatiotemporal compression. The highly correlated visual features are likely to change in spatial position, scale, orientation, and other attributes over time due to the dynamic nature of video. Building on this insight, we introduce FlashVID, a training-free inference acceleration framework for VLLMs. Specifically, FlashVID utilizes Attention and Diversity-based Token Selection (ADTS) to select the most representative tokens for basic video representation, then applies Tree-based Spatiotemporal Token Merging (TSTM) for fine-grained spatiotemporal redundancy elimination. Extensive experiments conducted on three representative VLLMs across five video understanding benchmarks demonstrate the effectiveness and generalization of our method. Notably, by retaining only 10% of visual tokens, FlashVID preserves 99.1% of the performance of LLaVA-OneVision. Consequently, FlashVID can serve as a training-free and plug-and-play module for extending long video frames, which enables a 10x increase in video frame input to Qwen2.5-VL, resulting in a relative improvement of 8.6% within the same computational budget. Code is available at https://github.com/Fanziyang-v/FlashVID.
[307] ForecastOcc: Vision-based Semantic Occupancy Forecasting
Riya Mohan, Juana Valeria Hurtado, Rohit Mohan, Abhinav Valada
Main category: cs.CV
TL;DR: ForecastOcc: First vision-based framework for joint semantic occupancy forecasting that predicts future occupancy states and semantic categories directly from camera images without external maps.
Details
Motivation: Existing occupancy forecasting methods focus on motion categories (static/dynamic) but lack semantic information. Current semantic approaches rely on separate networks for past occupancy predictions, leading to error accumulation and preventing direct learning of spatio-temporal features from images.Method: Proposes ForecastOcc with novel architecture: temporal cross-attention forecasting module, 2D-to-3D view transformer, 3D encoder for occupancy prediction, and semantic occupancy head for voxel-level forecasts across multiple horizons. Evaluated in multi-view (Occ3D-nuScenes) and monocular (SemanticKITTI) settings.
Result: Outperforms adapted baselines on both datasets, establishing first benchmark for monocular semantic occupancy forecasting on SemanticKITTI. Produces semantically rich, future-aware predictions capturing scene dynamics and semantics.
Conclusion: ForecastOcc enables joint semantic occupancy forecasting directly from images, addressing limitations of existing methods and providing critical scene understanding for autonomous driving applications.
Abstract: Autonomous driving requires forecasting both geometry and semantics over time to effectively reason about future environment states. Existing vision-based occupancy forecasting methods focus on motion-related categories such as static and dynamic objects, while semantic information remains largely absent. Recent semantic occupancy forecasting approaches address this gap but rely on past occupancy predictions obtained from separate networks. This makes current methods sensitive to error accumulation and prevents learning spatio-temporal features directly from images. In this work, we present ForecastOcc, the first framework for vision-based semantic occupancy forecasting that jointly predicts future occupancy states and semantic categories. Our framework yields semantic occupancy forecasts for multiple horizons directly from past camera images, without relying on externally estimated maps. We evaluate ForecastOcc in two complementary settings: multi-view forecasting on the Occ3D-nuScenes dataset and monocular forecasting on SemanticKITTI, where we establish the first benchmark for this task. We introduce the first baselines by adapting two 2D forecasting modules within our framework. Importantly, we propose a novel architecture that incorporates a temporal cross-attention forecasting module, a 2D-to-3D view transformer, a 3D encoder for occupancy prediction, and a semantic occupancy head for voxel-level forecasts across multiple horizons. Extensive experiments on both datasets show that ForecastOcc consistently outperforms baselines, yielding semantically rich, future-aware predictions that capture scene dynamics and semantics critical for autonomous driving.
[308] Improved cystic hygroma detection from prenatal imaging using ultrasound-specific self-supervised representation learning
Youssef Megahed, Robin Ducharme, Inok Lee, Inbal Willner, Adrian D. C. Chan, Mark Walker, Steven Hawken
Main category: cs.CV
TL;DR: Self-supervised pretraining with USF-MAE improves cystic hygroma detection in first-trimester ultrasound images compared to supervised DenseNet-169 baseline.
Details
Motivation: Cystic hygroma detection in prenatal ultrasound is important but limited by small labelled datasets; self-supervised pretraining could improve automated detection.Method: Fine-tuned Ultrasound Self-Supervised Foundation Model with Masked Autoencoding (USF-MAE) pretrained on 370k unlabelled ultrasound images for binary classification of normal vs cystic hygroma cases.
Result: USF-MAE outperformed DenseNet-169 baseline with accuracy 0.96 vs 0.93, sensitivity 0.94 vs 0.92, specificity 0.98 vs 0.94, ROC-AUC 0.98 vs 0.94; improvements statistically significant (p=0.0057).
Conclusion: Ultrasound-specific self-supervised pretraining enables accurate, robust deep learning detection of cystic hygroma, supporting scalable early screening programs.
Abstract: Cystic hygroma is a high-risk prenatal ultrasound finding that portends high rates of chromosomal abnormalities, structural malformations, and adverse pregnancy outcomes. Automated detection can increase reproducibility and support scalable early screening programs, but supervised deep learning methods are limited by small labelled datasets. This study assesses whether ultrasound-specific self-supervised pretraining can facilitate accurate, robust deep learning detection of cystic hygroma in first-trimester ultrasound images. We fine-tuned the Ultrasound Self-Supervised Foundation Model with Masked Autoencoding (USF-MAE), pretrained on over 370,000 unlabelled ultrasound images, for binary classification of normal controls and cystic hygroma cases used in this study. Performance was evaluated on the same curated ultrasound dataset, preprocessing pipeline, and 4-fold cross-validation protocol as for the DenseNet-169 baseline, using accuracy, sensitivity, specificity, and the area under the receiver operating characteristic curve (ROC-AUC). Model interpretability was analyzed qualitatively using Score-CAM visualizations. USF-MAE outperformed the DenseNet-169 baseline on all evaluation metrics. The proposed model yielded a mean accuracy of 0.96, sensitivity of 0.94, specificity of 0.98, and ROC-AUC of 0.98 compared to 0.93, 0.92, 0.94, and 0.94 for the DenseNet-169 baseline, respectively. Qualitative Score-CAM visualizations of model predictions demonstrated clinical relevance by highlighting expected regions in the fetal neck for both positive and negative cases. Paired statistical analysis using a Wilcoxon signed-rank test confirmed that performance improvements achieved by USF-MAE were statistically significant (p = 0.0057).
[309] PhysDrape: Learning Explicit Forces and Collision Constraints for Physically Realistic Garment Draping
Minghai Chen, Mingyuan Liu, Yuxiang Huan
Main category: cs.CV
TL;DR: PhysDrape: A hybrid neural-physical solver for garment draping that combines neural inference with explicit geometric solvers in a differentiable pipeline to resolve the trade-off between geometric feasibility and physical plausibility in collision handling.
Details
Motivation: Existing deep learning-based garment draping methods struggle with robust collision handling, creating a trade-off between geometric feasibility (avoiding mesh distortion) and physical plausibility (avoiding interpenetration). Soft penalty approaches fail to guarantee physical validity while preserving mesh structure.Method: PhysDrape integrates neural inference with explicit geometric solvers in a fully differentiable pipeline: 1) Physics-Informed Graph Neural Network conditioned on physics-enriched graph predicts residual displacements, 2) Learnable Force Solver resolves unbalanced forces from StVK model for quasi-static equilibrium, 3) Differentiable Projection strictly enforces collision constraints against body surface.
Result: PhysDrape achieves state-of-the-art performance with negligible interpenetration and significantly lower strain energy compared to baselines, demonstrating superior physical fidelity and robustness in real-time garment draping.
Conclusion: The hybrid neural-physical approach successfully resolves the conflict between geometric feasibility and physical plausibility in garment draping by guaranteeing physical validity through explicit constraints while enabling end-to-end learning for physically consistent predictions.
Abstract: Deep learning-based garment draping has emerged as a promising alternative to traditional Physics-Based Simulation (PBS), yet robust collision handling remains a critical bottleneck. Most existing methods enforce physical validity through soft penalties, creating an intrinsic trade-off between geometric feasibility and physical plausibility: penalizing collisions often distorts mesh structure, while preserving shape leads to interpenetration. To resolve this conflict, we present PhysDrape, a hybrid neural-physical solver for physically realistic garment draping driven by explicit forces and constraints. Unlike soft-constrained frameworks, PhysDrape integrates neural inference with explicit geometric solvers in a fully differentiable pipeline. Specifically, we propose a Physics-Informed Graph Neural Network conditioned on a physics-enriched graph – encoding material parameters and body proximity – to predict residual displacements. Crucially, we integrate a differentiable two-stage solver: first, a learnable Force Solver iteratively resolves unbalanced forces derived from the Saint Venant-Kirchhoff (StVK) model to ensure quasi-static equilibrium; second, a Differentiable Projection strictly enforces collision constraints against the body surface. This differentiable design guarantees physical validity through explicit constraints, while enabling end-to-end learning to optimize the network for physically consistent predictions. Extensive experiments demonstrate that PhysDrape achieves state-of-the-art performance, ensuring negligible interpenetration with significantly lower strain energy compared to existing baselines, achieving superior physical fidelity and robustness in real-time.
[310] MIND: Benchmarking Memory Consistency and Action Control in World Models
Yixuan Ye, Xuanyu Lu, Yuxin Jiang, Yuchao Gu, Rui Zhao, Qiwei Liang, Jiachun Pan, Fengda Zhang, Weijia Wu, Alex Jinpeng Wang
Main category: cs.CV
TL;DR: MIND is a new benchmark for evaluating world models’ memory consistency and action control abilities using 250 high-quality videos across first/third-person perspectives with varied action spaces.
Details
Motivation: There's a lack of unified benchmarks for evaluating fundamental abilities of world models in understanding, remembering, and predicting dynamic visual environments, particularly for memory consistency and action control across different viewpoints and action spaces.Method: Created MIND benchmark with 250 high-quality videos (100 first-person + 100 third-person clips with shared action space, plus 25+25 clips across varied action spaces) covering 8 diverse scenes. Designed evaluation framework measuring memory consistency (temporal stability and contextual coherence) and action control. Also introduced MIND-World as an interactive Video-to-World baseline for benchmarking.
Result: Extensive experiments demonstrate MIND’s completeness and reveal key challenges in current world models: difficulty maintaining long-term memory consistency and generalizing across different action spaces.
Conclusion: MIND provides the first open-domain closed-loop revisited benchmark for evaluating world models’ core abilities, highlighting current limitations and providing a foundation for future research in this area.
Abstract: World models aim to understand, remember, and predict dynamic visual environments, yet a unified benchmark for evaluating their fundamental abilities remains lacking. To address this gap, we introduce MIND, the first open-domain closed-loop revisited benchmark for evaluating Memory consIstency and action coNtrol in worlD models. MIND contains 250 high-quality videos at 1080p and 24 FPS, including 100 (first-person) + 100 (third-person) video clips under a shared action space and 25 + 25 clips across varied action spaces covering eight diverse scenes. We design an efficient evaluation framework to measure two core abilities: memory consistency and action control, capturing temporal stability and contextual coherence across viewpoints. Furthermore, we design various action spaces, including different character movement speeds and camera rotation angles, to evaluate the action generalization capability across different action spaces under shared scenes. To facilitate future performance benchmarking on MIND, we introduce MIND-World, a novel interactive Video-to-World baseline. Extensive experiments demonstrate the completeness of MIND and reveal key challenges in current world models, including the difficulty of maintaining long-term memory consistency and generalizing across action spaces. Project page: https://csu-jpg.github.io/MIND.github.io/
[311] Enhanced Mixture 3D CGAN for Completion and Generation of 3D Objects
Yahia Hamdi, Nicolas Andrialovanirina, Kélig Mahé, Emilie Poisson Caillault
Main category: cs.CV
TL;DR: MoE-DCGAN combines mixture of experts with 3D convolutional GANs for improved 3D object generation and completion, using specialized generators and dynamic capacity constraints.
Details
Motivation: GANs struggle with complex 3D data distributions, incomplete inputs, and computational demands. MoE models offer better performance and efficiency through specialized sub-networks.Method: Integrates deep 3D convolutional GANs with MoE framework, using multiple specialized generators and auxiliary loss-free dynamic capacity constraint mechanism for categorical generator selection.
Result: Model effectively generates and completes 3D shapes with varying missing regions, outperforming state-of-the-art approaches in both quantitative and qualitative evaluations.
Conclusion: MoE-DCGAN successfully handles complex 3D data challenges, balancing specialization, training stability, and computational efficiency for 3D voxel processing.
Abstract: The generation and completion of 3D objects represent a transformative challenge in computer vision. Generative Adversarial Networks (GANs) have recently demonstrated strong potential in synthesizing realistic visual data. However, they often struggle to capture complex and diverse data distributions, particularly in scenarios involving incomplete inputs or significant missing regions. These challenges arise mainly from the high computational requirements and the difficulty of modeling heterogeneous and structurally intricate data, which restrict their applicability in real-world settings. Mixture of Experts (MoE) models have emerged as a promising solution to these limitations. By dynamically selecting and activating the most relevant expert sub-networks for a given input, MoEs improve both performance and efficiency. In this paper, we investigate the integration of Deep 3D Convolutional GANs (CGANs) with a MoE framework to generate high-quality 3D models and reconstruct incomplete or damaged objects. The proposed architecture incorporates multiple generators, each specialized to capture distinct modalities within the dataset. Furthermore, an auxiliary loss-free dynamic capacity constraint (DCC) mechanism is introduced to guide the selection of categorical generators, ensuring a balance between specialization, training stability, and computational efficiency, which is critical for 3D voxel processing. We evaluated the model’s ability to generate and complete shapes with missing regions of varying sizes and compared its performance with state-of-the-art approaches. Both quantitative and qualitative results confirm the effectiveness of the proposed MoE-DCGAN in handling complex 3D data.
[312] Vanilla Group Equivariant Vision Transformer: Simple and Effective
Jiahong Fu, Qi Xie, Deyu Meng, Zongben Xu
Main category: cs.CV
TL;DR: A framework for building Vision Transformers with guaranteed equivariance by systematically making key components (patch embedding, self-attention, positional encodings, down/up-sampling) equivariant to symmetry priors.
Details
Motivation: Existing equivariant ViTs struggle to balance performance with equivariance due to challenges in achieving holistic equivariant modifications across diverse ViT modules, particularly in harmonizing self-attention with patch embedding.Method: Proposes a straightforward framework that systematically renders key ViT components equivariant: patch embedding, self-attention, positional encodings, and down/up-sampling. The approach constructs ViTs with guaranteed equivariance and serves as a plug-and-play replacement that scales to architectures like Swin Transformers.
Result: Extensive experiments show that the equivariant ViTs consistently improve performance and data efficiency across a wide spectrum of vision tasks.
Conclusion: The proposed framework provides a theoretically grounded and practically versatile approach to building equivariant Vision Transformers that effectively incorporate symmetry priors as inductive biases.
Abstract: Incorporating symmetry priors as inductive biases to design equivariant Vision Transformers (ViTs) has emerged as a promising avenue for enhancing their performance. However, existing equivariant ViTs often struggle to balance performance with equivariance, primarily due to the challenge of achieving holistic equivariant modifications across the diverse modules in ViTs-particularly in harmonizing the Self-Attention mechanism with Patch Embedding. To address this, we propose a straightforward framework that systematically renders key ViT components, including patch embedding, self-attention, positional encodings, and Down/Up-Sampling, equivariant, thereby constructing ViTs with guaranteed equivariance. The resulting architecture serves as a plug-and-play replacement that is both theoretically grounded and practically versatile, scaling seamlessly even to Swin Transformers. Extensive experiments demonstrate that our equivariant ViTs consistently improve performance and data efficiency across a wide spectrum of vision tasks.
[313] Weak to Strong: VLM-Based Pseudo-Labeling as a Weakly Supervised Training Strategy in Multimodal Video-based Hidden Emotion Understanding Tasks
Yufei Wang, Haixu Liu, Tianxiang Xu, Chuancheng Shi, Hongsheng Xing
Main category: cs.CV
TL;DR: A multimodal weak-supervision framework for concealed emotion recognition in videos using visual features, key-point sequences, and interview transcripts, achieving state-of-the-art results on iMiGUE dataset.
Details
Motivation: To address the challenge of automatically recognizing concealed emotions in videos, which is difficult due to subtle expressions and class imbalance, using a multimodal approach with weak supervision.Method: Uses YOLO for face detection, DINOv2 for visual features, Gemini 2.5 Pro with CoT+Reflection for pseudo-label generation, OpenPose for key-points with MLP backbone, and Transformer encoding with BERT for text. Combines pre-training, fine-tuning, and pseudo-label integration.
Result: Achieves over 0.69 accuracy on iMiGUE dataset (improving from under 0.6), establishes new public benchmark, and shows MLP key-point backbone can match or surpass GCN-based methods.
Conclusion: The proposed multimodal weak-supervision framework effectively recognizes concealed emotions, demonstrates the viability of simplified MLP backbones for key-point modeling, and shows the value of pseudo-label generation through LLM reasoning.
Abstract: To tackle the automatic recognition of “concealed emotions” in videos, this paper proposes a multimodal weak-supervision framework and achieves state-of-the-art results on the iMiGUE tennis-interview dataset. First, YOLO 11x detects and crops human portraits frame-by-frame, and DINOv2-Base extracts visual features from the cropped regions. Next, by integrating Chain-of-Thought and Reflection prompting (CoT + Reflection), Gemini 2.5 Pro automatically generates pseudo-labels and reasoning texts that serve as weak supervision for downstream models. Subsequently, OpenPose produces 137-dimensional key-point sequences, augmented with inter-frame offset features; the usual graph neural network backbone is simplified to an MLP to efficiently model the spatiotemporal relationships of the three key-point streams. An ultra-long-sequence Transformer independently encodes both the image and key-point sequences, and their representations are concatenated with BERT-encoded interview transcripts. Each modality is first pre-trained in isolation, then fine-tuned jointly, with pseudo-labeled samples merged into the training set for further gains. Experiments demonstrate that, despite severe class imbalance, the proposed approach lifts accuracy from under 0.6 in prior work to over 0.69, establishing a new public benchmark. The study also validates that an “MLP-ified” key-point backbone can match - or even surpass - GCN-based counterparts in this task.
[314] Picasso: Holistic Scene Reconstruction with Physics-Constrained Sampling
Xihang Yu, Rajat Talak, Lorenzo Shaikewitz, Luca Carlone
Main category: cs.CV
TL;DR: Picasso: A physics-constrained reconstruction pipeline for multi-object scenes that ensures physical plausibility by reasoning holistically about object interactions, non-penetration, and physics.
Details
Motivation: Geometrically accurate scene reconstructions can still be physically incorrect (e.g., object interpenetration, unstable equilibrium), making it difficult to predict dynamic behavior for simulation-based planning and control of contact-rich behaviors.Method: Physics-constrained reconstruction pipeline that builds multi-object scene reconstructions by considering geometry, non-penetration, and physics. Uses fast rejection sampling that reasons over multi-object interactions, leveraging an inferred object contact graph to guide samples.
Result: Outperforms state-of-the-art on both the new Picasso dataset (10 contact-rich real-world scenes) and YCB-V dataset, providing reconstructions that are physically plausible and more aligned with human intuition.
Conclusion: Object pose and shape estimation requires holistic scene reasoning accounting for object interactions and physical plausibility, which Picasso successfully achieves through physics-constrained reconstruction.
Abstract: In the presence of occlusions and measurement noise, geometrically accurate scene reconstructions – which fit the sensor data – can still be physically incorrect. For instance, when estimating the poses and shapes of objects in the scene and importing the resulting estimates into a simulator, small errors might translate to implausible configurations including object interpenetration or unstable equilibrium. This makes it difficult to predict the dynamic behavior of the scene using a digital twin, an important step in simulation-based planning and control of contact-rich behaviors. In this paper, we posit that object pose and shape estimation requires reasoning holistically over the scene (instead of reasoning about each object in isolation), accounting for object interactions and physical plausibility. Towards this goal, our first contribution is Picasso, a physics-constrained reconstruction pipeline that builds multi-object scene reconstructions by considering geometry, non-penetration, and physics. Picasso relies on a fast rejection sampling method that reasons over multi-object interactions, leveraging an inferred object contact graph to guide samples. Second, we propose the Picasso dataset, a collection of 10 contact-rich real-world scenes with ground truth annotations, as well as a metric to quantify physical plausibility, which we open-source as part of our benchmark. Finally, we provide an extensive evaluation of Picasso on our newly introduced dataset and on the YCB-V dataset, and show it largely outperforms the state of the art while providing reconstructions that are both physically plausible and more aligned with human intuition.
[315] DICE: Disentangling Artist Style from Content via Contrastive Subspace Decomposition in Diffusion Models
Tong Zhang, Ru Zhang, Jianyi Liu
Main category: cs.CV
TL;DR: DICE is a training-free framework for on-the-fly artist style erasure in diffusion models, using contrastive subspace decomposition to disentangle style from content without requiring explicit style specification.
Details
Motivation: The proliferation of diffusion models has made style mimicry effortless, raising copyright and intellectual-property risks. Existing countermeasures require costly weight editing or explicit style specification, limiting practicality for deployment-side safety.Method: DICE constructs contrastive triplets to distinguish style vs. non-style features in latent space, formalizing disentanglement as a generalized eigenvalue problem to identify style subspace. Uses Adaptive Attention Decoupling Editing to dynamically assess style concentration per token and perform differential suppression and content enhancement on QKV vectors.
Result: DICE achieves superior balance between thoroughness of style erasure and preservation of content integrity, with only 3 seconds additional overhead for style disentanglement.
Conclusion: DICE provides a practical and efficient technique for curbing style mimicry in diffusion models through training-free style purification that preserves user-intended content.
Abstract: The recent proliferation of diffusion models has made style mimicry effortless, enabling users to imitate unique artistic styles without authorization. In deployed platforms, this raises copyright and intellectual-property risks and calls for reliable protection. However, existing countermeasures either require costly weight editing as new styles emerge or rely on an explicitly specified editing style, limiting their practicality for deployment-side safety. To address this challenge, we propose DICE (Disentanglement of artist Style from Content via Contrastive Subspace Decomposition), a training-free framework for on-the-fly artist style erasure. Unlike style editing that require an explicitly specified replacement style, DICE performs style purification, removing the artist’s characteristics while preserving the user-intended content. Our core insight is that a model cannot truly comprehend the artist style from a single text or image alone. Consequently, we abandon the traditional paradigm of identifying style from isolated samples. Instead, we construct contrastive triplets to compel the model to distinguish between style and non-style features in the latent space. By formalizing this disentanglement process as a solvable generalized eigenvalue problem, we achieve precise identification of the style subspace. Furthermore, we introduce an Adaptive Attention Decoupling Editing strategy dynamically assesses the style concentration of each token and performs differential suppression and content enhancement on the QKV vectors. Extensive experiments demonstrate that DICE achieves a superior balance between the thoroughness of style erasure and the preservation of content integrity. DICE introduces an additional overhead of only 3 seconds to disentangle style, providing a practical and efficient technique for curbing style mimicry.
[316] ReRoPE: Repurposing RoPE for Relative Camera Control
Chunyang Li, Yuanbo Yang, Jiahao Shao, Hongyu Zhou, Katja Schwarz, Yiyi Liao
Main category: cs.CV
TL;DR: ReRoPE is a plug-and-play framework that injects relative camera pose information into pre-trained video diffusion models using underutilized spectral bands in Rotary Positional Embeddings, enabling precise camera viewpoint control without retraining.
Details
Motivation: Existing methods for controllable camera viewpoint video generation use camera poses relative to fixed references (like first frames), which lack shift-invariance and cause poor generalization and accumulated drift. Relative camera pose embeddings between arbitrary view pairs offer better robustness but integrating them into pre-trained video diffusion models without expensive retraining or architectural changes is challenging.Method: ReRoPE leverages the insight that Rotary Positional Embeddings (RoPE) in existing models underutilize their full spectral bandwidth, especially low-frequency components. The method seamlessly injects relative camera pose information into these underutilized bands, enabling precise camera control while preserving pre-trained generative priors. This is a plug-and-play framework that doesn’t require retraining or architectural modifications.
Result: The method is evaluated on image-to-video (I2V) and video-to-video (V2V) tasks for camera control accuracy and visual fidelity. Results show ReRoPE offers a training-efficient path toward controllable, high-fidelity video generation with precise camera viewpoint control.
Conclusion: ReRoPE provides an effective solution for integrating relative camera pose information into pre-trained video diffusion models, addressing the shift-invariance problem while maintaining strong generative priors and enabling precise camera viewpoint control for video generation applications.
Abstract: Video generation with controllable camera viewpoints is essential for applications such as interactive content creation, gaming, and simulation. Existing methods typically adapt pre-trained video models using camera poses relative to a fixed reference, e.g., the first frame. However, these encodings lack shift-invariance, often leading to poor generalization and accumulated drift. While relative camera pose embeddings defined between arbitrary view pairs offer a more robust alternative, integrating them into pre-trained video diffusion models without prohibitive training costs or architectural changes remains challenging. We introduce ReRoPE, a plug-and-play framework that incorporates relative camera information into pre-trained video diffusion models without compromising their generation capability. Our approach is based on the insight that Rotary Positional Embeddings (RoPE) in existing models underutilize their full spectral bandwidth, particularly in the low-frequency components. By seamlessly injecting relative camera pose information into these underutilized bands, ReRoPE achieves precise control while preserving strong pre-trained generative priors. We evaluate our method on both image-to-video (I2V) and video-to-video (V2V) tasks in terms of camera control accuracy and visual fidelity. Our results demonstrate that ReRoPE offers a training-efficient path toward controllable, high-fidelity video generation. See project page for more results: https://sisyphe-lee.github.io/ReRoPE/
[317] When and How Much to Imagine: Adaptive Test-Time Scaling with World Models for Visual Spatial Reasoning
Shoubin Yu, Yue Zhang, Zun Wang, Jaehong Yoon, Huaxiu Yao, Mingyu Ding, Mohit Bansal
Main category: cs.CV
TL;DR: AVIC: Adaptive test-time framework that selectively invokes visual imagination for spatial reasoning, analyzing when imagination is beneficial vs. harmful
Details
Motivation: Current MLLMs struggle with visual spatial reasoning when answers depend on unseen viewpoints. While world models can help with visual imagination, indiscriminate imagination increases computation and can degrade performance by introducing misleading evidence. Need to understand when imagination is necessary, beneficial, or harmful.Method: Introduces AVIC, an adaptive test-time framework with world models that explicitly reasons about sufficiency of current visual evidence before selectively invoking and scaling visual imagination. Uses a decision mechanism to determine when to imagine and how much imagination to use.
Result: Across spatial reasoning benchmarks (SAT, MMSI) and embodied navigation (R2R), results show clear scenarios where imagination is critical, marginal, or detrimental. Selective control matches or outperforms fixed imagination strategies with substantially fewer world-model calls and language tokens.
Conclusion: Test-time visual imagination should be treated as a controllable resource for spatial reasoning. Selective imagination control enables efficient and reliable spatial reasoning by avoiding unnecessary computation and misleading evidence.
Abstract: Despite rapid progress in Multimodal Large Language Models (MLLMs), visual spatial reasoning remains unreliable when correct answers depend on how a scene would appear under unseen or alternative viewpoints. Recent work addresses this by augmenting reasoning with world models for visual imagination, but questions such as when imagination is actually necessary, how much of it is beneficial, and when it becomes harmful, remain poorly understood. In practice, indiscriminate imagination can increase computation and even degrade performance by introducing misleading evidence. In this work, we present an in-depth analysis of test-time visual imagination as a controllable resource for spatial reasoning. We study when static visual evidence is sufficient, when imagination improves reasoning, and how excessive or unnecessary imagination affects accuracy and efficiency. To support this analysis, we introduce AVIC, an adaptive test-time framework with world models that explicitly reasons about the sufficiency of current visual evidence before selectively invoking and scaling visual imagination. Across spatial reasoning benchmarks (SAT, MMSI) and an embodied navigation benchmark (R2R), our results reveal clear scenarios where imagination is critical, marginal, or detrimental, and show that selective control can match or outperform fixed imagination strategies with substantially fewer world-model calls and language tokens. Overall, our findings highlight the importance of analyzing and controlling test-time imagination for efficient and reliable spatial reasoning.
[318] ViT-5: Vision Transformers for The Mid-2020s
Feng Wang, Sucheng Ren, Tiezheng Zhang, Predrag Neskovic, Anand Bhattad, Cihang Xie, Alan Yuille
Main category: cs.CV
TL;DR: ViT-5 modernizes Vision Transformer backbones with architectural improvements from recent years while keeping the core Attention-FFN structure, achieving better performance on both understanding and generation tasks.
Details
Motivation: To systematically update Vision Transformer architectures by incorporating architectural advancements from the past five years, creating a more modern and performant backbone that can serve as a simple drop-in replacement for vanilla ViT models.Method: Conducted component-wise refinement of Vision Transformers including normalization, activation functions, positional encoding, gating mechanisms, and learnable tokens while preserving the canonical Attention-FFN structure. These updates form the ViT-5 architecture.
Result: ViT-5 consistently outperforms state-of-the-art plain Vision Transformers across understanding and generation benchmarks. Achieves 84.2% top-1 accuracy on ImageNet-1k classification (vs 83.8% for DeiT-III-Base) and 1.84 FID in diffusion modeling (vs 2.06 with vanilla ViT).
Conclusion: ViT-5 offers a simple drop-in upgrade over vanilla ViT with improved representation learning, favorable spatial reasoning, and reliable task transfer, making it suitable for mid-2020s vision backbones aligned with contemporary foundation-model practices.
Abstract: This work presents a systematic investigation into modernizing Vision Transformer backbones by leveraging architectural advancements from the past five years. While preserving the canonical Attention-FFN structure, we conduct a component-wise refinement involving normalization, activation functions, positional encoding, gating mechanisms, and learnable tokens. These updates form a new generation of Vision Transformers, which we call ViT-5. Extensive experiments demonstrate that ViT-5 consistently outperforms state-of-the-art plain Vision Transformers across both understanding and generation benchmarks. On ImageNet-1k classification, ViT-5-Base reaches 84.2% top-1 accuracy under comparable compute, exceeding DeiT-III-Base at 83.8%. ViT-5 also serves as a stronger backbone for generative modeling: when plugged into an SiT diffusion framework, it achieves 1.84 FID versus 2.06 with a vanilla ViT backbone. Beyond headline metrics, ViT-5 exhibits improved representation learning and favorable spatial reasoning behavior, and transfers reliably across tasks. With a design aligned with contemporary foundation-model practices, ViT-5 offers a simple drop-in upgrade over vanilla ViT for mid-2020s vision backbones.
[319] VidVec: Unlocking Video MLLM Embeddings for Video-Text Retrieval
Issar Tzachor, Dvir Samuel, Rami Ben-Ari
Main category: cs.CV
TL;DR: MLLMs can achieve state-of-the-art video retrieval performance without visual fine-tuning by combining intermediate-layer embeddings with text-based alignment on video captions
Details
Motivation: Current generative MLLMs adapted as embedding extractors for video tasks underperform compared to Video Foundation Models, and there's a need to better leverage MLLMs for video-text embedding and retrievalMethod: 1) Systematic layer-wise analysis of MLLMs showing intermediate layers encode task-relevant information; 2) Combine intermediate-layer embeddings with calibrated MLLM head for zero-shot retrieval; 3) Lightweight text-based alignment strategy mapping dense video captions to short summaries for video-text embedding learning without visual supervision
Result: Achieves state-of-the-art results across common video retrieval benchmarks, outperforming current methods often by substantial margins, without any fine-tuning beyond text
Conclusion: MLLMs can be effectively leveraged for video-text retrieval through careful analysis of layer representations and text-based alignment, achieving strong performance without visual fine-tuning
Abstract: Recent studies have adapted generative Multimodal Large Language Models (MLLMs) into embedding extractors for vision tasks, typically through fine-tuning to produce universal representations. However, their performance on video remains inferior to Video Foundation Models (VFMs). In this paper, we focus on leveraging MLLMs for video-text embedding and retrieval. We first conduct a systematic layer-wise analysis, showing that intermediate (pre-trained) MLLM layers already encode substantial task-relevant information. Leveraging this insight, we demonstrate that combining intermediate-layer embeddings with a calibrated MLLM head yields strong zero-shot retrieval performance without any training. Building on these findings, we introduce a lightweight text-based alignment strategy which maps dense video captions to short summaries and enables task-related video-text embedding learning without visual supervision. Remarkably, without any fine-tuning beyond text, our method outperforms current methods, often by a substantial margin, achieving state-of-the-art results across common video retrieval benchmarks.
[320] MMLSv2: A Multimodal Dataset for Martian Landslide Detection in Remote Sensing Imagery
Sidike Paheding, Abel Reyes-Angulo, Leo Thomas Ramos, Angel D. Sappa, Rajaneesh A., Hiral P. B., Sajin Kumar K. S., Thomas Oommen
Main category: cs.CV
TL;DR: MMLSv2 is a multimodal Martian landslide segmentation dataset with 7 bands (RGB, elevation, slope, thermal inertia, grayscale) and 664 images plus 276 isolated test images for evaluating spatial generalization.
Details
Motivation: There's a need for comprehensive multimodal datasets for landslide segmentation on Martian surfaces to advance research in planetary science and remote sensing, particularly for assessing model robustness and generalization across geographically disjoint regions.Method: Created a multimodal dataset with seven bands including RGB, digital elevation model, slope, thermal inertia, and grayscale channels. Dataset includes 664 images with standard splits plus 276 isolated test images from geographically disjoint regions to evaluate spatial generalization.
Result: The dataset supports stable training and achieves competitive performance with multiple segmentation models, though challenges remain in fragmented, elongated, and small-scale landslide regions. Evaluation on isolated test set shows noticeable performance drop, indicating increased difficulty and highlighting value for assessing model robustness.
Conclusion: MMLSv2 provides a valuable multimodal resource for Martian landslide segmentation research, particularly for testing model generalization across different geographical regions, with the isolated test set offering important insights into spatial generalization capabilities.
Abstract: We present MMLSv2, a dataset for landslide segmentation on Martian surfaces. MMLSv2 consists of multimodal imagery with seven bands: RGB, digital elevation model, slope, thermal inertia, and grayscale channels. MMLSv2 comprises 664 images distributed across training, validation, and test splits. In addition, an isolated test set of 276 images from a geographically disjoint region from the base dataset is released to evaluate spatial generalization. Experiments conducted with multiple segmentation models show that the dataset supports stable training and achieves competitive performance, while still posing challenges in fragmented, elongated, and small-scale landslide regions. Evaluation on the isolated test set leads to a noticeable performance drop, indicating increased difficulty and highlighting its value for assessing model robustness and generalization beyond standard in-distribution settings. Dataset will be available at: https://github.com/MAIN-Lab/MMLS_v2
[321] Building Damage Detection using Satellite Images and Patch-Based Transformer Methods
Smriti Siva, Jan Cross-Zamirski
Main category: cs.CV
TL;DR: Small Vision Transformers (DINOv2-small and DeiT) with targeted patch-based preprocessing and frozen-head fine-tuning achieve competitive damage classification performance on the xBD satellite imagery dataset despite noisy, imbalanced data.
Details
Motivation: Rapid building damage assessment from satellite imagery is critical for post-disaster response, but existing models face challenges with label noise and severe class imbalance in satellite data. The xBD dataset provides a standardized benchmark, but Vision Transformers' performance on this noisy, imbalanced data needs evaluation.Method: Proposes a targeted patch-based preprocessing pipeline to isolate structural features and minimize background noise. Uses DINOv2-small and DeiT Vision Transformers with a frozen-head fine-tuning strategy to keep computational requirements manageable. Evaluates through accuracy, precision, recall, and macro-averaged F1 scores.
Result: Small ViT architectures with the novel training method achieve competitive macro-averaged F1 scores relative to prior CNN baselines for disaster classification on the xBD dataset.
Conclusion: Vision Transformers with targeted preprocessing and efficient fine-tuning can effectively handle noisy, imbalanced satellite imagery data for building damage assessment, providing a scalable solution for post-disaster response.
Abstract: Rapid building damage assessment is critical for post-disaster response. Damage classification models built on satellite imagery provide a scalable means of obtaining situational awareness. However, label noise and severe class imbalance in satellite data create major challenges. The xBD dataset offers a standardized benchmark for building-level damage across diverse geographic regions. In this study, we evaluate Vision Transformer (ViT) model performance on the xBD dataset, specifically investigating how these models distinguish between types of structural damage when training on noisy, imbalanced data. In this study, we specifically evaluate DINOv2-small and DeiT for multi-class damage classification. We propose a targeted patch-based pre-processing pipeline to isolate structural features and minimize background noise in training. We adopt a frozen-head fine-tuning strategy to keep computational requirements manageable. Model performance is evaluated through accuracy, precision, recall, and macro-averaged F1 scores. We show that small ViT architectures with our novel training method achieves competitive macro-averaged F1 relative to prior CNN baselines for disaster classification.
[322] MambaFusion: Adaptive State-Space Fusion for Multimodal 3D Object Detection
Venkatraman Narayanan, Bala Sai, Rahul Ahuja, Pratik Likhar, Varun Ravi Kumar, Senthil Yogamani
Main category: cs.CV
TL;DR: MambaFusion: A unified multimodal 3D object detection framework for autonomous driving that combines selective state-space models with windowed transformers for efficient global context modeling, uses reliability-aware fusion gates for camera-LiDAR feature alignment, and employs structure-conditioned diffusion for uncertainty-aware detection.
Details
Motivation: Reliable 3D object detection is crucial for autonomous driving, but existing multimodal fusion approaches using cameras and LiDAR face challenges including inefficient context modeling, spatially invariant fusion, and reasoning under uncertainty. Current BEV-based frameworks struggle with these issues despite making progress.Method: MambaFusion interleaves selective state-space models (SSMs) with windowed transformers for linear-time global context propagation while preserving local geometry. It uses multi-modal token alignment and reliability-aware fusion gates to dynamically re-weight camera-LiDAR features based on spatial confidence and calibration consistency. A structure-conditioned diffusion head integrates graph-based reasoning with uncertainty-aware denoising for physically plausible detection.
Result: MambaFusion establishes new state-of-the-art performance on nuScenes benchmarks while operating with linear-time complexity. The framework demonstrates robust, temporally stable, and interpretable 3D perception suitable for real-world autonomous driving systems.
Conclusion: Coupling SSM-based efficiency with reliability-driven fusion yields superior 3D perception for autonomous driving. The framework addresses key challenges in multimodal fusion and provides a promising direction for efficient, adaptive, and physically grounded 3D object detection systems.
Abstract: Reliable 3D object detection is fundamental to autonomous driving, and multimodal fusion algorithms using cameras and LiDAR remain a persistent challenge. Cameras provide dense visual cues but ill posed depth; LiDAR provides a precise 3D structure but sparse coverage. Existing BEV-based fusion frameworks have made good progress, but they have difficulties including inefficient context modeling, spatially invariant fusion, and reasoning under uncertainty. We introduce MambaFusion, a unified multi-modal detection framework that achieves efficient, adaptive, and physically grounded 3D perception. MambaFusion interleaves selective state-space models (SSMs) with windowed transformers to propagate the global context in linear time while preserving local geometric fidelity. A multi-modal token alignment (MTA) module and reliability-aware fusion gates dynamically re-weight camera-LiDAR features based on spatial confidence and calibration consistency. Finally, a structure-conditioned diffusion head integrates graph-based reasoning with uncertainty-aware denoising, enforcing physical plausibility, and calibrated confidence. MambaFusion establishes new state-of-the-art performance on nuScenes benchmarks while operating with linear-time complexity. The framework demonstrates that coupling SSM-based efficiency with reliability-driven fusion yields robust, temporally stable, and interpretable 3D perception for real-world autonomous driving systems.
[323] Learning Self-Correction in Vision-Language Models via Rollout Augmentation
Yi Ding, Ziliang Qiu, Bolian Li, Ruqi Zhang
Main category: cs.CV
TL;DR: Octopus framework uses rollout recombination to generate dense self-correction examples for vision-language models, improving RL training efficiency and enabling controllable self-correction capabilities.
Details
Motivation: Existing reinforcement learning methods for vision-language models struggle with learning self-correction behaviors due to sparse learning signals, as effective self-correction occurs rarely during training.Method: Proposes correction-specific rollouts (Octopus) - an RL rollout augmentation framework that synthesizes dense self-correction examples by recombining existing rollouts, plus a response-masking strategy to decouple self-correction from direct reasoning.
Result: Octopus-8B achieves state-of-the-art performance across 7 benchmarks among open-source VLMs, outperforming the best RLVR baseline by 1.0 score while requiring only 0.72× training time per step.
Conclusion: The Octopus framework effectively addresses sparse learning signals in self-correction training for VLMs through rollout recombination and response-masking, enabling efficient learning of controllable self-correction capabilities.
Abstract: Self-correction is essential for solving complex reasoning problems in vision-language models (VLMs). However, existing reinforcement learning (RL) methods struggle to learn it, as effective self-correction behaviors emerge only rarely, making learning signals extremely sparse. To address this challenge, we propose correction-specific rollouts (Octopus), an RL rollout augmentation framework that synthesizes dense self-correction examples by recombining existing rollouts. This augmentation simultaneously improves sample efficiency due to rollout reuse and stabilizes RL optimization through balanced supervision. Furthermore, we introduce a response-masking strategy that decouples self-correction from direct reasoning, avoiding signal conflicts and enabling both behaviors to be learned effectively. Building on this, we introduce Octopus-8B, a reasoning VLM with controllable self-correction capability. Across 7 benchmarks, it achieves SoTA performance among open-source VLMs, outperforming the best RLVR baseline by 1.0 score while requiring only $0.72\times$ training time per step.
[324] Fields of The World: A Field Guide for Extracting Agricultural Field Boundaries
Isaac Corley, Hannah Kerner, Caleb Robinson, Jennifer Marcus
Main category: cs.CV
TL;DR: FTW ecosystem provides global field boundary benchmark, pre-trained models, and tools for agricultural field segmentation and crop classification using satellite imagery.
Details
Motivation: Field boundary maps are essential for agricultural applications like crop monitoring and yield estimation, but creating them at scale is challenging. The FTW ecosystem aims to provide a comprehensive solution for global field boundary extraction and analysis.Method: Developed a benchmark of 1.6M field polygons across 24 countries, pre-trained segmentation models, and command-line inference tools. Uses MOSAIKS random convolutional features with FTW-derived field boundaries for crop type classification with limited labels.
Result: Achieved macro F1 scores of 0.65-0.75 for crop type classification. Pre-computed predictions cover five countries (4.76M km²) with median predicted field areas ranging from 0.06 ha (Rwanda) to 0.28 ha (Switzerland).
Conclusion: FTW ecosystem provides a scalable solution for agricultural field analysis, enabling applications from local-scale extraction to country-scale inference using cloud-optimized data.
Abstract: Field boundary maps are a building block for agricultural data products and support crop monitoring, yield estimation, and disease estimation. This tutorial presents the Fields of The World (FTW) ecosystem: a benchmark of 1.6M field polygons across 24 countries, pre-trained segmentation models, and command-line inference tools. We provide two notebooks that cover (1) local-scale field boundary extraction with crop classification and forest loss attribution, and (2) country-scale inference using cloud-optimized data. We use MOSAIKS random convolutional features and FTW derived field boundaries to map crop type at the field level and report macro F1 scores of 0.65–0.75 for crop type classification with limited labels. Finally, we show how to explore pre-computed predictions over five countries (4.76M km\textsuperscript{2}), with median predicted field areas from 0.06 ha (Rwanda) to 0.28 ha (Switzerland).
[325] Robustness of Vision Language Models Against Split-Image Harmful Input Attacks
Md Rafi Ur Rashid, MD Sadik Hossain Shanto, Vishnu Asutosh Dasu, Shagufta Mehnaz
Main category: cs.CV
TL;DR: SIVA introduces split-image visual jailbreak attacks that exploit VLMs’ safety alignment gaps by distributing harmful content across multiple image fragments, achieving superior transferability through adversarial knowledge distillation.
Details
Motivation: VLMs have strong safety alignment against traditional visual jailbreak attacks using holistic images, but their safety training doesn't account for harmful semantics distributed across multiple image fragments, creating a new vulnerability.Method: Progressive split-image attack strategies: 1) naive splitting, 2) adaptive white-box attack, 3) black-box transfer attack using novel adversarial knowledge distillation (Adv-KD) to improve cross-model transferability by distilling adversarial knowledge from a white-box surrogate model.
Result: Evaluations on three state-of-the-art VLMs and three jailbreak datasets show the strongest attack achieves up to 60% higher transfer success than existing baselines, demonstrating significant vulnerability in current VLM safety alignment.
Conclusion: Current VLM safety alignment is vulnerable to split-image attacks, and the paper proposes efficient mitigation strategies while highlighting the need for safety training that accounts for distributed harmful semantics across multiple images.
Abstract: Vision-Language Models (VLMs) are now a core part of modern AI. Recent work proposed several visual jailbreak attacks using single/ holistic images. However, contemporary VLMs demonstrate strong robustness against such attacks due to extensive safety alignment through preference optimization (e.g., RLHF). In this work, we identify a new vulnerability: while VLM pretraining and instruction tuning generalize well to split-image inputs, safety alignment is typically performed only on holistic images and does not account for harmful semantics distributed across multiple image fragments. Consequently, VLMs often fail to detect and refuse harmful split-image inputs, where unsafe cues emerge only after combining images. We introduce novel split-image visual jailbreak attacks (SIVA) that exploit this misalignment. Unlike prior optimization-based attacks, which exhibit poor black-box transferability due to architectural and prior mismatches across models, our attacks evolve in progressive phases from naive splitting to an adaptive white-box attack, culminating in a black-box transfer attack. Our strongest strategy leverages a novel adversarial knowledge distillation (Adv-KD) algorithm to substantially improve cross-model transferability. Evaluations on three state-of-the-art modern VLMs and three jailbreak datasets demonstrate that our strongest attack achieves up to 60% higher transfer success than existing baselines. Lastly, we propose efficient ways to address this critical vulnerability in the current VLM safety alignment.
[326] DAS-SK: An Adaptive Model Integrating Dual Atrous Separable and Selective Kernel CNN for Agriculture Semantic Segmentation
Mei Ling Chee, Thangarajah Akilan, Aparna Ravindra Phalke, Kanchan Keisham
Main category: cs.CV
TL;DR: DAS-SK is a lightweight semantic segmentation architecture for agricultural imagery that combines selective kernel convolution with dual atrous separable convolution for efficient multi-scale feature learning, achieving state-of-the-art performance with significantly reduced computational cost.
Details
Motivation: Agricultural semantic segmentation requires models that balance accuracy and computational efficiency for deployment on UAVs and edge devices, addressing limitations of existing models including large dataset requirements, limited spectral generalization, and high computational costs.Method: Proposes DAS-SK architecture that retrofits selective kernel convolution (SK-Conv) into dual atrous separable convolution (DAS-Conv) modules to enhance multi-scale feature learning. Enhances atrous spatial pyramid pooling (ASPP) to capture both fine-grained local structures and global context. Built on modified DeepLabV3 framework with MobileNetV3-Large and EfficientNet-B3 backbones.
Result: Achieves state-of-the-art performance across three benchmarks (LandCover.ai, VDD, PhenoBench) while being more efficient than CNN-, transformer-, and hybrid-based competitors. Requires up to 21x fewer parameters and 19x fewer GFLOPs than top-performing transformer models.
Conclusion: DAS-SK establishes a robust, efficient, and scalable solution for real-time agricultural robotics and high-resolution remote sensing, with potential for broader deployment in other vision domains.
Abstract: Semantic segmentation in high-resolution agricultural imagery demands models that strike a careful balance between accuracy and computational efficiency to enable deployment in practical systems. In this work, we propose DAS-SK, a novel lightweight architecture that retrofits selective kernel convolution (SK-Conv) into the dual atrous separable convolution (DAS-Conv) module to strengthen multi-scale feature learning. The model further enhances the atrous spatial pyramid pooling (ASPP) module, enabling the capture of fine-grained local structures alongside global contextual information. Built upon a modified DeepLabV3 framework with two complementary backbones - MobileNetV3-Large and EfficientNet-B3, the DAS-SK model mitigates limitations associated with large dataset requirements, limited spectral generalization, and the high computational cost that typically restricts deployment on UAVs and other edge devices. Comprehensive experiments across three benchmarks: LandCover.ai, VDD, and PhenoBench, demonstrate that DAS-SK consistently achieves state-of-the-art performance, while being more efficient than CNN-, transformer-, and hybrid-based competitors. Notably, DAS-SK requires up to 21x fewer parameters and 19x fewer GFLOPs than top-performing transformer models. These findings establish DAS-SK as a robust, efficient, and scalable solution for real-time agricultural robotics and high-resolution remote sensing, with strong potential for broader deployment in other vision domains.
[327] PEGAsus: 3D Personalization of Geometry and Appearance
Jingyu Hu, Bin Hu, Ka-Hei Hui, Haipeng Li, Zhengzhe Liu, Daniel Cohen-Or, Chi-Wing Fu
Main category: cs.CV
TL;DR: PEGAsus is a framework for personalized 3D shape generation that learns reusable geometric and appearance attributes from reference shapes and composes them with text prompts to create novel shapes.
Details
Motivation: The paper aims to enable fine-grained control over 3D shape generation by learning reusable shape concepts that can be flexibly composed with text prompts, supporting personalized shape creation even in cross-category scenarios.Method: 1) Formulates 3D shape personalization as extracting category-agnostic geometric and appearance attributes; 2) Uses progressive optimization to learn shape concepts at geometry and appearance levels separately; 3) Extends to region-wise concept learning with context-aware and context-free losses.
Result: PEGAsus effectively extracts attributes from diverse reference shapes and composes them with text to synthesize new shapes, outperforming state-of-the-art methods in both quantitative and qualitative evaluations.
Conclusion: The framework enables fine-grained control over shape generation and supports diverse, personalized results, demonstrating superior performance in challenging cross-category scenarios.
Abstract: We present PEGAsus, a new framework capable of generating Personalized 3D shapes by learning shape concepts at both Geometry and Appearance levels. First, we formulate 3D shape personalization as extracting reusable, category-agnostic geometric and appearance attributes from reference shapes, and composing these attributes with text to generate novel shapes. Second, we design a progressive optimization strategy to learn shape concepts at both the geometry and appearance levels, decoupling the shape concept learning process. Third, we extend our approach to region-wise concept learning, enabling flexible concept extraction, with context-aware and context-free losses. Extensive experimental results show that PEGAsus is able to effectively extract attributes from a wide range of reference shapes and then flexibly compose these concepts with text to synthesize new shapes. This enables fine-grained control over shape generation and supports the creation of diverse, personalized results, even in challenging cross-category scenarios. Both quantitative and qualitative experiments demonstrate that our approach outperforms existing state-of-the-art solutions.
[328] Generative Regression for Left Ventricular Ejection Fraction Estimation from Echocardiography Video
Jinrong Lv, Xun Gong, Zhaohuan Li, Weili Jiang
Main category: cs.CV
TL;DR: A generative regression approach using multimodal conditional score-based diffusion models to estimate LVEF from echocardiograms, addressing the ill-posed inverse problem by modeling continuous posterior distributions rather than deterministic predictions.
Details
Motivation: LVEF estimation from echocardiograms is an ill-posed inverse problem with inherent noise, artifacts, and limited viewing angles that create ambiguity. Single video sequences may map to distributions of plausible physiological values rather than unique ground truths. Standard regression approaches using MSE minimization force models to learn conditional expectations, which can yield misleading predictions when posterior distributions are multimodal or heavy-tailed, especially in pathological scenarios.Method: Proposes MCSDR (Multimodal Conditional Score-based Diffusion model for Regression), a probabilistic framework that models the continuous posterior distribution of LVEF conditioned on echocardiogram videos and patient demographic attribute priors. Uses a generative regression approach with score-based diffusion models to capture distributional uncertainty rather than deterministic point estimates.
Result: Extensive experiments on EchoNet-Dynamic, EchoNet-Pediatric, and CAMUS datasets demonstrate state-of-the-art performance. Qualitative analysis shows that generation trajectories exhibit distinct behaviors in cases with high noise or significant physiological variability, offering novel interpretability for AI-aided diagnosis.
Conclusion: The paper successfully demonstrates a paradigm shift from deterministic regression to generative regression for medical imaging tasks, showing that modeling continuous posterior distributions can improve performance and provide interpretability through generation trajectories, particularly valuable in ambiguous pathological scenarios.
Abstract: Estimating Left Ventricular Ejection Fraction (LVEF) from echocardiograms constitutes an ill-posed inverse problem. Inherent noise, artifacts, and limited viewing angles introduce ambiguity, where a single video sequence may map not to a unique ground truth, but rather to a distribution of plausible physiological values. Prevailing deep learning approaches typically formulate this task as a standard regression problem that minimizes the Mean Squared Error (MSE). However, this paradigm compels the model to learn the conditional expectation, which may yield misleading predictions when the underlying posterior distribution is multimodal or heavy-tailed – a common phenomenon in pathological scenarios. In this paper, we investigate the paradigm shift from deterministic regression toward generative regression. We propose the Multimodal Conditional Score-based Diffusion model for Regression (MCSDR), a probabilistic framework designed to model the continuous posterior distribution of LVEF conditioned on echocardiogram videos and patient demographic attribute priors. Extensive experiments conducted on the EchoNet-Dynamic, EchoNet-Pediatric, and CAMUS datasets demonstrate that MCSDR achieves state-of-the-art performance. Notably, qualitative analysis reveals that the generation trajectories of our model exhibit distinct behaviors in cases characterized by high noise or significant physiological variability, thereby offering a novel layer of interpretability for AI-aided diagnosis.
[329] Geospatial-Reasoning-Driven Vocabulary-Agnostic Remote Sensing Semantic Segmentation
Chufeng Zhou, Jian Wang, Xinyuan Liu, Xiaokang Zhang
Main category: cs.CV
TL;DR: GR-CoT framework enhances open-vocabulary semantic segmentation in remote sensing by integrating geospatial reasoning with MLLMs to resolve semantic ambiguity in land-cover classification.
Details
Motivation: Existing open-vocabulary segmentation methods in remote sensing rely on passive visual-text mapping, lacking geospatial context and causing semantic ambiguity when land-cover classes have similar spectral features but different semantic attributes.Method: Proposes Geospatial Reasoning Chain-of-Thought (GR-CoT) framework with two components: offline knowledge distillation stream to establish fine-grained category interpretation standards, and online instance reasoning stream that performs sequential reasoning (macro-scenario anchoring, visual feature decoupling, knowledge-driven decision synthesis) to generate image-adaptive vocabulary for pixel-level alignment.
Result: Extensive experiments on LoveDA and GID5 benchmarks demonstrate superiority of the approach over existing methods.
Conclusion: GR-CoT framework effectively enhances scene understanding capabilities of MLLMs for open-vocabulary semantic segmentation in remote sensing by integrating geospatial reasoning to resolve semantic ambiguity.
Abstract: Open-vocabulary semantic segmentation has emerged as a promising research direction in remote sensing, enabling the recognition of diverse land-cover types beyond pre-defined category sets. However, existing methods predominantly rely on the passive mapping of visual features and textual embeddings. This ``appearance-based" paradigm lacks geospatial contextual awareness, leading to severe semantic ambiguity and misclassification when encountering land-cover classes with similar spectral features but distinct semantic attributes. To address this, we propose a Geospatial Reasoning Chain-of-Thought (GR-CoT) framework designed to enhance the scene understanding capabilities of Multimodal Large Language Models (MLLMs), thereby guiding open-vocabulary segmentation models toward precise mapping. The framework comprises two collaborative components: an offline knowledge distillation stream and an online instance reasoning stream. The offline stream establishes fine-grained category interpretation standards to resolve semantic conflicts between similar land-cover types. During online inference, the framework executes a sequential reasoning process involving macro-scenario anchoring, visual feature decoupling, and knowledge-driven decision synthesis. This process generates an image-adaptive vocabulary that guides downstream models to achieve pixel-level alignment with correct geographical semantics. Extensive experiments on the LoveDA and GID5 benchmarks demonstrate the superiority of our approach.
[330] Chain-of-Caption: Training-free improvement of multimodal large language model on referring expression comprehension
Yik Lung Pang, Changjae Oh
Main category: cs.CV
TL;DR: Training-free Chain-of-Caption framework improves referring expression comprehension in MLLMs by combining multiple visual/textual contexts, achieving 5-30% performance gains over baselines.
Details
Motivation: While MLLMs achieve high accuracy on REC benchmarks through scaling, performance can be further improved using techniques like Chain-of-Thought and tool use that provide additional context. The paper aims to analyze various techniques for providing visual/textual context via tool use and their effects on REC performance.Method: Proposes Chain-of-Caption, a training-free framework that combines multiple textual and visual contexts to improve REC performance in MLLMs. Analyzes effects of individual context types (visual/textual) and their combinations via tool use without requiring fine-tuning.
Result: Individual textual or visual context improves REC performance without fine-tuning. Combined multiple contexts in Chain-of-Caption framework shows 5% to 30% performance gain over baseline models on accuracy at various IoU thresholds across RefCOCO/RefCOCOg/RefCOCO+ and Ref-L4 datasets.
Conclusion: Training-free context combination via Chain-of-Caption significantly enhances MLLM performance on referring expression comprehension tasks, demonstrating the value of multi-context integration without requiring model retraining.
Abstract: Given a textual description, the task of referring expression comprehension (REC) involves the localisation of the referred object in an image. Multimodal large language models (MLLMs) have achieved high accuracy on REC benchmarks through scaling up the model size and training data. Moreover, the performance of MLLMs can be further improved using techniques such as Chain-of-Thought and tool use, which provides additional visual or textual context to the model. In this paper, we analyse the effect of various techniques for providing additional visual and textual context via tool use to the MLLM and its effect on the REC task. Furthermore, we propose a training-free framework named Chain-of-Caption to improve the REC performance of MLLMs. We perform experiments on RefCOCO/RefCOCOg/RefCOCO+ and Ref-L4 datasets and show that individual textual or visual context can improve the REC performance without any fine-tuning. By combining multiple contexts, our training-free framework shows between 5% to 30% performance gain over the baseline model on accuracy at various Intersection over Union (IoU) thresholds.
[331] Efficient-SAM2: Accelerating SAM2 with Object-Aware Visual Encoding and Memory Retrieval
Jing Zhang, Zhikai Li, Xuewen Liu, Qingyi Gu
Main category: cs.CV
TL;DR: Efficient-SAM2 accelerates SAM2 for video object segmentation by exploiting sparse perception patterns to eliminate redundant computations in both image encoder and memory attention.
Details
Motivation: SAM2 shows excellent video segmentation performance but has heavy computational burden for real-time applications. Current efficiency improvements focus on retraining lightweight backbones, with little exploration of post-training acceleration through computational redundancy elimination.Method: Proposes Efficient-SAM2 with two key techniques: 1) Object-aware Sparse Window Routing (SWR) for image encoder - uses previous-frame decoder cues to route background regions to lightweight shortcut branch; 2) Object-aware Sparse Memory Retrieval (SMR) for memory attention - allows only salient memory tokens to participate in computation, reusing saliency patterns from first recollection.
Result: Achieves 1.68x speedup on SAM2.1-L model with only 1.0% accuracy drop on SA-V test set, using negligible additional parameters and minimal training overhead.
Conclusion: Efficient-SAM2 successfully accelerates SAM2 by exploiting its sparse perception patterns, demonstrating that post-training optimization can significantly improve efficiency while maintaining accuracy for video object segmentation.
Abstract: Segment Anything Model 2 (SAM2) shows excellent performance in video object segmentation tasks; however, the heavy computational burden hinders its application in real-time video processing. Although there have been efforts to improve the efficiency of SAM2, most of them focus on retraining a lightweight backbone, with little exploration into post-training acceleration. In this paper, we observe that SAM2 exhibits sparse perception pattern as biological vision, which provides opportunities for eliminating redundant computation and acceleration: i) In mask decoder, the attention primarily focuses on the foreground objects, whereas the image encoder in the earlier stage exhibits a broad attention span, which results in unnecessary computation to background regions. ii) In memory bank, only a small subset of tokens in each frame contribute significantly to memory attention, and the salient regions exhibit temporal consistency, making full-token computation redundant. With these insights, we propose Efficient-SAM2, which promotes SAM2 to adaptively focus on object regions while eliminating task-irrelevant computations, thereby significantly improving inference efficiency. Specifically, for image encoder, we propose object-aware Sparse Window Routing (SWR), a window-level computation allocation mechanism that leverages the consistency and saliency cues from the previous-frame decoder to route background regions into a lightweight shortcut branch. Moreover, for memory attention, we propose object-aware Sparse Memory Retrieval (SMR), which allows only the salient memory tokens in each frame to participate in computation, with the saliency pattern reused from their first recollection. With negligible additional parameters and minimal training overhead, Efficient-SAM2 delivers 1.68x speedup on SAM2.1-L model with only 1.0% accuracy drop on SA-V test set.
[332] Generating Adversarial Events: A Motion-Aware Point Cloud Framework
Hongwei Ren, Youxin Jiang, Qifei Gu, Xiangqian Wu
Main category: cs.CV
TL;DR: MA-ADV: First adversarial attack framework for event cameras using point cloud representations, achieving 100% attack success with minimal perturbations
Details
Motivation: Event cameras are used in safety-critical applications like autonomous driving, but deep neural networks for event processing are vulnerable to adversarial attacks. Current research is limited due to non-differentiable event representations preventing gradient-based attacks.Method: Proposes MA-ADV framework using point cloud representations for events. Uses diffusion-based approach to smooth perturbations while leveraging spatial-temporal relationships. Employs sample-wise Adam optimization, iterative refinement, and binary search for minimal-cost perturbations.
Result: Achieves 100% attack success rate with minimal perturbation cost. Demonstrates enhanced robustness against defenses, highlighting security vulnerabilities in event-based perception systems.
Conclusion: MA-ADV successfully addresses the challenge of adversarial attacks on event cameras, revealing critical security issues in event-based systems that need attention for safety-critical applications.
Abstract: Event cameras have been widely adopted in safety-critical domains such as autonomous driving, robotics, and human-computer interaction. A pressing challenge arises from the vulnerability of deep neural networks to adversarial examples, which poses a significant threat to the reliability of event-based systems. Nevertheless, research into adversarial attacks on events is scarce. This is primarily due to the non-differentiable nature of mainstream event representations, which hinders the extension of gradient-based attack methods. In this paper, we propose MA-ADV, a novel \textbf{M}otion-\textbf{A}ware \textbf{Adv}ersarial framework. To the best of our knowledge, this is the first work to generate adversarial events by leveraging point cloud representations. MA-ADV accounts for high-frequency noise in events and employs a diffusion-based approach to smooth perturbations, while fully leveraging the spatial and temporal relationships among events. Finally, MA-ADV identifies the minimal-cost perturbation through a combination of sample-wise Adam optimization, iterative refinement, and binary search. Extensive experimental results validate that MA-ADV ensures a 100% attack success rate with minimal perturbation cost, and also demonstrate enhanced robustness against defenses, underscoring the critical security challenges facing future event-based perception systems.
[333] Moving Beyond Functional Connectivity: Time-Series Modeling for fMRI-Based Brain Disorder Classification
Guoqi Yu, Xiaowei Hu, Angelica I. Aviles-Rivero, Anqi Qiu, Shujun Wang
Main category: cs.CV
TL;DR: DeCI framework for fMRI brain disorder classification using temporal modeling of raw BOLD signals instead of traditional functional connectivity approaches.
Details
Motivation: Traditional fMRI analysis reduces 4D BOLD signals to static 2D functional connectivity matrices using Pearson correlation, which discards temporal dynamics and captures only linear relationships between brain regions.Method: Proposes DeCI framework with two key principles: (1) Cycle and Drift Decomposition to disentangle oscillatory fluctuations and slow baseline trends within each ROI, and (2) Channel-Independence to model each ROI separately for improved robustness and reduced overfitting.
Result: DeCI achieves superior classification accuracy and generalization compared to both traditional FC-based approaches and other temporal baselines across five public datasets.
Conclusion: Advocates for a shift toward end-to-end temporal modeling in fMRI analysis to better capture complex brain dynamics, with DeCI demonstrating the value of directly modeling temporal information.
Abstract: Functional magnetic resonance imaging (fMRI) enables non-invasive brain disorder classification by capturing blood-oxygen-level-dependent (BOLD) signals. However, most existing methods rely on functional connectivity (FC) via Pearson correlation, which reduces 4D BOLD signals to static 2D matrices, discarding temporal dynamics and capturing only linear inter-regional relationships. In this work, we benchmark state-of-the-art temporal models (e.g., time-series models such as PatchTST, TimesNet, and TimeMixer) on raw BOLD signals across five public datasets. Results show these models consistently outperform traditional FC-based approaches, highlighting the value of directly modeling temporal information such as cycle-like oscillatory fluctuations and drift-like slow baseline trends. Building on this insight, we propose DeCI, a simple yet effective framework that integrates two key principles: (i) Cycle and Drift Decomposition to disentangle cycle and drift within each ROI (Region of Interest); and (ii) Channel-Independence to model each ROI separately, improving robustness and reducing overfitting. Extensive experiments demonstrate that DeCI achieves superior classification accuracy and generalization compared to both FC-based and temporal baselines. Our findings advocate for a shift toward end-to-end temporal modeling in fMRI analysis to better capture complex brain dynamics. The code is available at https://github.com/Levi-Ackman/DeCI.
[334] PISCO: Precise Video Instance Insertion with Sparse Control
Xiangbo Gao, Renjie Li, Xinghao Chen, Yuheng Wu, Suofei Feng, Qing Yin, Zhengzhong Tu
Main category: cs.CV
TL;DR: PISCO is a video diffusion model for precise video instance insertion with sparse keyframe control, enabling targeted modifications in AI-assisted filmmaking while maintaining scene integrity.
Details
Motivation: The paper addresses the need for fine-grained, controllable video generation in professional AI-assisted filmmaking, moving beyond general generation that requires extensive prompt engineering and cherry-picking. Specifically, it focuses on video instance insertion - inserting specific instances into existing footage while maintaining scene integrity, which requires precise spatial-temporal placement, physically consistent scene interaction, and preservation of original dynamics with minimal user effort.Method: PISCO is a video diffusion model that allows users to specify arbitrary sparse keyframe controls (single keyframe, start-end keyframes, or sparse keyframes at arbitrary timestamps) and automatically propagates object appearance, motion, and interaction. To address distribution shift from sparse conditioning in pretrained video diffusion models, the authors introduce Variable-Information Guidance for robust conditioning and Distribution-Preserving Temporal Masking to stabilize temporal generation, along with geometry-aware conditioning for realistic scene adaptation. They also construct PISCO-Bench, a benchmark with verified instance annotations and paired clean background videos.
Result: Experiments demonstrate that PISCO consistently outperforms strong inpainting and video editing baselines under sparse control conditions. The model exhibits clear, monotonic performance improvements as additional control signals are provided, evaluated using both reference-based and reference-free perceptual metrics on the PISCO-Bench benchmark.
Conclusion: PISCO represents an important advancement in controllable video generation for professional filmmaking applications, enabling precise video instance insertion with minimal user effort through sparse keyframe control while maintaining scene integrity and physical consistency.
Abstract: The landscape of AI video generation is undergoing a pivotal shift: moving beyond general generation - which relies on exhaustive prompt-engineering and “cherry-picking” - towards fine-grained, controllable generation and high-fidelity post-processing. In professional AI-assisted filmmaking, it is crucial to perform precise, targeted modifications. A cornerstone of this transition is video instance insertion, which requires inserting a specific instance into existing footage while maintaining scene integrity. Unlike traditional video editing, this task demands several requirements: precise spatial-temporal placement, physically consistent scene interaction, and the faithful preservation of original dynamics - all achieved under minimal user effort. In this paper, we propose PISCO, a video diffusion model for precise video instance insertion with arbitrary sparse keyframe control. PISCO allows users to specify a single keyframe, start-and-end keyframes, or sparse keyframes at arbitrary timestamps, and automatically propagates object appearance, motion, and interaction. To address the severe distribution shift induced by sparse conditioning in pretrained video diffusion models, we introduce Variable-Information Guidance for robust conditioning and Distribution-Preserving Temporal Masking to stabilize temporal generation, together with geometry-aware conditioning for realistic scene adaptation. We further construct PISCO-Bench, a benchmark with verified instance annotations and paired clean background videos, and evaluate performance using both reference-based and reference-free perceptual metrics. Experiments demonstrate that PISCO consistently outperforms strong inpainting and video editing baselines under sparse control, and exhibits clear, monotonic performance improvements as additional control signals are provided. Project page: xiangbogaobarry.github.io/PISCO.
[335] Tighnari v2: Mitigating Label Noise and Distribution Shift in Multimodal Plant Distribution Prediction via Mixture of Experts and Weakly Supervised Learning
Haixu Liu, Yufei Wang, Tianxiang Xu, Chuancheng Shi, Hongsheng Xing
Main category: cs.CV
TL;DR: A multimodal fusion framework for plant distribution prediction that combines Presence-Absence (PA) and Presence-Only (PO) data using satellite imagery, tabular features, and time-series modeling with a mixture-of-experts approach to handle data sparsity and distribution shifts.
Details
Motivation: Plant distribution prediction faces challenges due to sparse and biased observational data. PA data are accurate but limited, while PO data have broad coverage but suffer from label noise in negative samples. There's a need to leverage both data types effectively while handling geographic distribution shifts between training and test samples.Method: Proposes a multimodal fusion framework with: 1) Pseudo-label aggregation for PO data using satellite imagery geographic coverage; 2) Swin Transformer Base for satellite imagery, TabM network for tabular features, Temporal Swin Transformer for time-series; 3) Stackable serial tri-modal cross-attention for modality fusion; 4) Mixture-of-experts approach partitioning test samples by spatial proximity to PA samples, using different models trained on distinct datasets for each partition.
Result: Experiments on GeoLifeCLEF 2025 dataset show superior predictive performance in scenarios with limited PA coverage and pronounced distribution shifts compared to baseline approaches.
Conclusion: The proposed multimodal fusion framework effectively addresses challenges in plant distribution prediction by leveraging complementary strengths of PA and PO data while handling distribution shifts through a mixture-of-experts approach, demonstrating improved performance in real-world constrained scenarios.
Abstract: Large-scale, cross-species plant distribution prediction plays a crucial role in biodiversity conservation, yet modeling efforts in this area still face significant challenges due to the sparsity and bias of observational data. Presence-Absence (PA) data provide accurate and noise-free labels, but are costly to obtain and limited in quantity; Presence-Only (PO) data, by contrast, offer broad spatial coverage and rich spatiotemporal distribution, but suffer from severe label noise in negative samples. To address these real-world constraints, this paper proposes a multimodal fusion framework that fully leverages the strengths of both PA and PO data. We introduce an innovative pseudo-label aggregation strategy for PO data based on the geographic coverage of satellite imagery, enabling geographic alignment between the label space and remote sensing feature space. In terms of model architecture, we adopt Swin Transformer Base as the backbone for satellite imagery, utilize the TabM network for tabular feature extraction, retain the Temporal Swin Transformer for time-series modeling, and employ a stackable serial tri-modal cross-attention mechanism to optimize the fusion of heterogeneous modalities. Furthermore, empirical analysis reveals significant geographic distribution shifts between PA training and test samples, and models trained by directly mixing PO and PA data tend to experience performance degradation due to label noise in PO data. To address this, we draw on the mixture-of-experts paradigm: test samples are partitioned according to their spatial proximity to PA samples, and different models trained on distinct datasets are used for inference and post-processing within each partition. Experiments on the GeoLifeCLEF 2025 dataset demonstrate that our approach achieves superior predictive performance in scenarios with limited PA coverage and pronounced distribution shifts.
[336] CAE-AV: Improving Audio-Visual Learning via Cross-modal Interactive Enrichment
Yunzuo Hu, Wen Li, Jing Zhang
Main category: cs.CV
TL;DR: CAE-AV is a novel framework that addresses audio-visual misalignment through two complementary modules: CASTE for dynamic spatio-temporal balancing based on audio-visual agreement, and CASE for injecting cross-modal semantic guidance, achieving SOTA on multiple benchmarks.
Details
Motivation: Audio-visual learning suffers from modality misalignment caused by off-screen sources and background clutter, leading current methods to amplify irrelevant regions/moments, unstable training, and degraded representation quality.Method: Proposes CAE-AV framework with two modules: 1) CASTE dynamically balances spatial and temporal relations by evaluating frame-level audio-visual agreement, and 2) CASE injects cross-modal semantic guidance into selected spatio-temporal positions. Also includes lightweight objectives: caption-to-modality InfoNCE, visual-audio consistency, and entropy regularization.
Result: With frozen backbones, CAE-AV achieves state-of-the-art performance on AVE, AVVP, AVS, and AVQA benchmarks. Qualitative analyses validate robustness against audio-visual misalignment.
Conclusion: CAE-AV effectively addresses audio-visual misalignment through complementary spatio-temporal enrichment and semantic guidance modules, demonstrating strong performance across multiple audio-visual understanding tasks.
Abstract: Audio-visual learning suffers from modality misalignment caused by off-screen sources and background clutter, and current methods usually amplify irrelevant regions or moments, leading to unstable training and degraded representation quality. To address this challenge, we proposed a novel Caption-aligned and Agreement-guided Enhancement framework (CAE-AV) for audio-visual learning, which used two complementary modules: Cross-modal Agreement-guided Spatio-Temporal Enrichment (CASTE) and Caption-Aligned Saliency-guided Enrichment (CASE) to relieve audio-visual misalignment. CASTE dynamically balances spatial and temporal relations by evaluating frame-level audio-visual agreement, ensuring that key information is captured from both preceding and subsequent frames under misalignment. CASE injects cross-modal semantic guidance into selected spatio-temporal positions, leveraging high-level semantic cues to further alleviate misalignment. In addition, we design lightweight objectives, caption-to-modality InfoNCE, visual-audio consistency, and entropy regularization to guide token selection and strengthen cross-modal semantic alignment. With frozen backbones, CAE-AV achieves state-of-the-art performance on AVE, AVVP, AVS, and AVQA benchmarks, and qualitative analyses further validate its robustness against audio-visual misalignment.
[337] Language-Guided Transformer Tokenizer for Human Motion Generation
Sheng Yan, Yong Wang, Xin Du, Junsong Yuan, Mengyuan Liu
Main category: cs.CV
TL;DR: LG-Tok: Language-guided motion tokenization using transformers to create compact semantic representations for efficient motion generation, outperforming state-of-the-art on HumanML3D and Motion-X benchmarks.
Details
Motivation: Current motion tokenization methods face a trade-off: more tokens improve reconstruction quality but make generation harder to learn. Need compact, semantic representations that maintain quality while reducing complexity.Method: Proposes Language-Guided Tokenization (LG-Tok) that aligns natural language with motion at tokenization stage using Transformer-based tokenizer with attention mechanisms. Includes language-drop scheme for language-free guidance during generation.
Result: Achieves Top-1 scores of 0.542 (HumanML3D) and 0.582 (Motion-X), outperforming MARDM (0.500/0.528). FID scores of 0.057/0.088 vs 0.114/0.147. LG-Tok-mini uses half tokens while maintaining competitive performance.
Conclusion: Language guidance enables efficient motion tokenization with compact semantic representations, improving both reconstruction quality and generation simplicity while supporting both language-conditioned and language-free generation.
Abstract: In this paper, we focus on motion discrete tokenization, which converts raw motion into compact discrete tokens–a process proven crucial for efficient motion generation. In this paradigm, increasing the number of tokens is a common approach to improving motion reconstruction quality, but more tokens make it more difficult for generative models to learn. To maintain high reconstruction quality while reducing generation complexity, we propose leveraging language to achieve efficient motion tokenization, which we term Language-Guided Tokenization (LG-Tok). LG-Tok aligns natural language with motion at the tokenization stage, yielding compact, high-level semantic representations. This approach not only strengthens both tokenization and detokenization but also simplifies the learning of generative models. Furthermore, existing tokenizers predominantly adopt convolutional architectures, whose local receptive fields struggle to support global language guidance. To this end, we propose a Transformer-based Tokenizer that leverages attention mechanisms to enable effective alignment between language and motion. Additionally, we design a language-drop scheme, in which language conditions are randomly removed during training, enabling the detokenizer to support language-free guidance during generation. On the HumanML3D and Motion-X generation benchmarks, LG-Tok achieves Top-1 scores of 0.542 and 0.582, outperforming state-of-the-art methods (MARDM: 0.500 and 0.528), and with FID scores of 0.057 and 0.088, respectively, versus 0.114 and 0.147. LG-Tok-mini uses only half the tokens while maintaining competitive performance (Top-1: 0.521/0.588, FID: 0.085/0.071), validating the efficiency of our semantic representations.
[338] UrbanGraphEmbeddings: Learning and Evaluating Spatially Grounded Multimodal Embeddings for Urban Science
Jie Zhang, Xingtong Yu, Yuan Fang, Rudi Stouffs, Zdravko Trivic
Main category: cs.CV
TL;DR: UGData dataset with spatial graph alignment, UGE training strategy for multimodal embeddings, and UGBench benchmark for urban understanding tasks.
Details
Motivation: Urban understanding requires spatial grounding, but existing datasets lack explicit alignment between street-view images and urban structure, limiting transferable multimodal embeddings.Method: Introduces UGData (spatially grounded dataset with graph-aligned supervision), UGE (two-stage training combining instruction-guided contrastive learning with graph-based spatial encoding), and UGBench benchmark for evaluation.
Result: UGE achieves up to 44% improvement in image retrieval and 30% in geolocation ranking on training cities, with over 30% and 22% gains on held-out cities.
Conclusion: Explicit spatial grounding significantly improves multimodal embeddings for spatially intensive urban tasks, demonstrating the value of structured spatial alignment in vision-language models.
Abstract: Learning transferable multimodal embeddings for urban environments is challenging because urban understanding is inherently spatial, yet existing datasets and benchmarks lack explicit alignment between street-view images and urban structure. We introduce UGData, a spatially grounded dataset that anchors street-view images to structured spatial graphs and provides graph-aligned supervision via spatial reasoning paths and spatial context captions, exposing distance, directionality, connectivity, and neighborhood context beyond image content. Building on UGData, we propose UGE, a two-stage training strategy that progressively and stably aligns images, text, and spatial structures by combining instruction-guided contrastive learning with graph-based spatial encoding. We finally introduce UGBench, a comprehensive benchmark to evaluate how spatially grounded embeddings support diverse urban understanding tasks – including geolocation ranking, image retrieval, urban perception, and spatial grounding. We develop UGE on multiple state-of-the-art VLM backbones, including Qwen2-VL, Qwen2.5-VL, Phi-3-Vision, and LLaVA1.6-Mistral, and train fixed-dimensional spatial embeddings with LoRA tuning. UGE built upon Qwen2.5-VL-7B backbone achieves up to 44% improvement in image retrieval and 30% in geolocation ranking on training cities, and over 30% and 22% gains respectively on held-out cities, demonstrating the effectiveness of explicit spatial grounding for spatially intensive urban tasks.
[339] What, Whether and How? Unveiling Process Reward Models for Thinking with Images Reasoning
Yujin Zhou, Pengcheng Wen, Jiale Chen, Boqin Yin, Han Zhu, Jiaming Ji, Juntao Dai, Chi-Min Chan, Sirui Han
Main category: cs.CV
TL;DR: First comprehensive benchmark for evaluating Process Reward Models (PRMs) in Large Vision Language Models under the “thinking with images” paradigm, with 1,206 annotated reasoning trajectories and analysis of 7 error types.
Details
Motivation: The "thinking with images" paradigm in LVLMs enables dynamic visual editing and re-encoding during reasoning, but introduces diverse errors. Existing PRM benchmarks are text-centric and inadequate for evaluating visual reasoning processes, creating a need for specialized evaluation frameworks.Method: 1) Analyzed reasoning trajectories and conducted guided search experiments with PRMs to define 7 fine-grained error types. 2) Constructed benchmark with 1,206 manually annotated reasoning trajectories spanning 4 categories and 16 subcategories. 3) Experimental evaluation of current LVLMs as PRMs, assessing performance across error types, evaluation biases, and sensitivity to reasoning step positions.
Result: Current LVLMs perform poorly as PRMs for visual reasoning processes, showing limited capabilities, significant performance disparities across error types, positive evaluation bias, and sensitivity to reasoning step positions. The benchmark effectively reveals these limitations.
Conclusion: The benchmark establishes crucial foundations for advancing PRMs in LVLMs, demonstrating the necessity for specialized PRMs and providing a comprehensive evaluation framework for the “thinking with images” paradigm.
Abstract: The rapid advancement of Large Vision Language Models (LVLMs) has demonstrated excellent abilities in various visual tasks. Building upon these developments, the thinking with images paradigm has emerged, enabling models to dynamically edit and re-encode visual information at each reasoning step, mirroring human visual processing. However, this paradigm introduces significant challenges as diverse errors may occur during reasoning processes. This necessitates Process Reward Models (PRMs) for distinguishing positive and negative reasoning steps, yet existing benchmarks for PRMs are predominantly text-centric and lack comprehensive assessment under this paradigm. To address these gaps, this work introduces the first comprehensive benchmark specifically designed for evaluating PRMs under the thinking with images paradigm. Our main contributions are: (1) Through extensive analysis of reasoning trajectories and guided search experiments with PRMs, we define 7 fine-grained error types and demonstrate both the necessity for specialized PRMs and the potential for improvement. (2) We construct a comprehensive benchmark comprising 1,206 manually annotated thinking with images reasoning trajectories spanning 4 categories and 16 subcategories for fine-grained evaluation of PRMs. (3) Our experimental analysis reveals that current LVLMs fall short as effective PRMs, exhibiting limited capabilities in visual reasoning process evaluation with significant performance disparities across error types, positive evaluation bias, and sensitivity to reasoning step positions. These findings demonstrate the effectiveness of our benchmark and establish crucial foundations for advancing PRMs in LVLMs.
[340] E-VAds: An E-commerce Short Videos Understanding Benchmark for MLLMs
Xianjie Liu, Yiman Hu, Liang Wu, Ping Hu, Yixiong Zou, Jian Xu, Bo Zheng
Main category: cs.CV
TL;DR: E-commerce short video benchmark with multi-modal density assessment, new dataset (E-VAds), and RL-based reasoning model (E-VAds-R1) for commercial intent understanding
Details
Motivation: Current video understanding models struggle with e-commerce short videos due to their goal-driven format, dense multi-modal signals, and lack of benchmarks focusing on commercial intent reasoningMethod: 1) Multi-modal information density assessment framework to quantify complexity; 2) E-VAds benchmark with 3,961 videos and 19,785 Q&A pairs; 3) E-VAds-R1 RL-based reasoning model with multi-grained reward design (MG-GRPO)
Result: E-commerce content shows substantially higher multi-modal density than mainstream datasets; E-VAds-R1 achieves 109.2% performance gain in commercial intent reasoning with few hundred training samples
Conclusion: E-commerce videos present a challenging frontier for video understanding; the proposed benchmark and RL-based model effectively address commercial intent reasoning in dense multi-modal content
Abstract: E-commerce short videos represent a high-revenue segment of the online video industry characterized by a goal-driven format and dense multi-modal signals. Current models often struggle with these videos because existing benchmarks focus primarily on general-purpose tasks and neglect the reasoning of commercial intent. In this work, we first propose a \textbf{multi-modal information density assessment framework} to quantify the complexity of this domain. Our evaluation reveals that e-commerce content exhibits substantially higher density across visual, audio, and textual modalities compared to mainstream datasets, establishing a more challenging frontier for video understanding. To address this gap, we introduce \textbf{E-commerce Video Ads Benchmark (E-VAds)}, which is the first benchmark specifically designed for e-commerce short video understanding. We curated 3,961 high-quality videos from Taobao covering a wide range of product categories and used a multi-agent system to generate 19,785 open-ended Q&A pairs. These questions are organized into two primary dimensions, namely Perception and Cognition and Reasoning, which consist of five distinct tasks. Finally, we develop \textbf{E-VAds-R1}, an RL-based reasoning model featuring a multi-grained reward design called \textbf{MG-GRPO}. This strategy provides smooth guidance for early exploration while creating a non-linear incentive for expert-level precision. Experimental results demonstrate that E-VAds-R1 achieves a 109.2% performance gain in commercial intent reasoning with only a few hundred training samples.
[341] Geometric Image Editing via Effects-Sensitive In-Context Inpainting with Diffusion Transformers
Shuo Zhang, Wenzhuo Wu, Huayu Zhang, Jiarong Cheng, Xianghao Zang, Chao Ban, Hao Sun, Zhongjiang He, Tianwei Cao, Kongming Liang, Zhanyu Ma
Main category: cs.CV
TL;DR: GeoEdit: A diffusion-based framework for precise geometric editing (translation, rotation, scaling) with realistic lighting/shadow effects using in-context generation and Effects-Sensitive Attention.
Details
Motivation: Existing diffusion models struggle with accurate geometric transformations (translation, rotation, scaling) in complex scenes and fail to model intricate lighting/shadow effects, leading to unrealistic editing results.Method: Proposes GeoEdit framework with: 1) Diffusion transformer module for in-context generation with integrated geometric transformations, 2) Effects-Sensitive Attention for enhanced lighting/shadow modeling, 3) RS-Objects dataset (120K+ image pairs) for training geometric editing.
Result: Extensive experiments show GeoEdit outperforms state-of-the-art methods in visual quality, geometric accuracy, and realism on public benchmarks.
Conclusion: GeoEdit effectively addresses geometric editing challenges in diffusion models while improving realism through better lighting/shadow modeling.
Abstract: Recent advances in diffusion models have significantly improved image editing. However, challenges persist in handling geometric transformations, such as translation, rotation, and scaling, particularly in complex scenes. Existing approaches suffer from two main limitations: (1) difficulty in achieving accurate geometric editing of object translation, rotation, and scaling; (2) inadequate modeling of intricate lighting and shadow effects, leading to unrealistic results. To address these issues, we propose GeoEdit, a framework that leverages in-context generation through a diffusion transformer module, which integrates geometric transformations for precise object edits. Moreover, we introduce Effects-Sensitive Attention, which enhances the modeling of intricate lighting and shadow effects for improved realism. To further support training, we construct RS-Objects, a large-scale geometric editing dataset containing over 120,000 high-quality image pairs, enabling the model to learn precise geometric editing while generating realistic lighting and shadows. Extensive experiments on public benchmarks demonstrate that GeoEdit consistently outperforms state-of-the-art methods in terms of visual quality, geometric accuracy, and realism.
[342] D$^2$-VR: Degradation-Robust and Distilled Video Restoration with Synergistic Optimization Strategy
Jianfeng Liang, Shaocheng Shen, Botao Xu, Qiang Hu, Xiaoyun Zhang
Main category: cs.CV
TL;DR: D²-VR: A single-image diffusion-based video restoration framework with low-step inference that addresses latency and temporal instability issues through degradation-robust flow alignment and adversarial distillation.
Details
Motivation: Current diffusion-based video restoration methods suffer from prohibitive inference latency and temporal instability when dealing with complex real-world degradations, limiting their practical deployment despite excellent perceptual quality.Method: 1) Degradation-Robust Flow Alignment (DRFA) module using confidence-aware attention to filter unreliable motion cues; 2) Adversarial distillation to compress diffusion sampling into few-step regime; 3) Synergistic optimization strategy to balance perceptual quality with temporal consistency.
Result: Achieves state-of-the-art performance while accelerating sampling process by 12× compared to previous methods.
Conclusion: D²-VR successfully addresses the latency and stability limitations of diffusion-based video restoration, making it more practical for real-world applications while maintaining high quality.
Abstract: The integration of diffusion priors with temporal alignment has emerged as a transformative paradigm for video restoration, delivering fantastic perceptual quality, yet the practical deployment of such frameworks is severely constrained by prohibitive inference latency and temporal instability when confronted with complex real-world degradations. To address these limitations, we propose \textbf{D$^2$-VR}, a single-image diffusion-based video-restoration framework with low-step inference. To obtain precise temporal guidance under severe degradation, we first design a Degradation-Robust Flow Alignment (DRFA) module that leverages confidence-aware attention to filter unreliable motion cues. We then incorporate an adversarial distillation paradigm to compress the diffusion sampling trajectory into a rapid few-step regime. Finally, a synergistic optimization strategy is devised to harmonize perceptual quality with rigorous temporal consistency. Extensive experiments demonstrate that D$^2$-VR achieves state-of-the-art performance while accelerating the sampling process by \textbf{12$\times$}
[343] RealSynCol: a high-fidelity synthetic colon dataset for 3D reconstruction applications
Chiara Lena, Davide Milesi, Alessandro Casella, Luca Carlini, Joseph C. Norton, James Martin, Bruno Scaglioni, Keith L. Obstein, Roberto De Sire, Marco Spadaccini, Cesare Hassan, Pietro Valdastri, Elena De Momi
Main category: cs.CV
TL;DR: RealSynCol: A highly realistic synthetic colonoscopy dataset with 28,130 frames, ground truth depth maps, optical flow, 3D meshes, and camera trajectories for training deep learning models for 3D reconstruction and navigation in colonoscopy.
Details
Motivation: Deep learning can improve colonoscopy through 3D reconstruction and comprehensive lesion visualization, but development is limited by scarcity of large-scale ground truth data from real clinical procedures.Method: Created synthetic dataset using colon geometries from 10 CT scans imported into virtual environment mimicking intraoperative conditions, rendered with realistic vascular textures, and paired with comprehensive ground truth annotations.
Result: Benchmark study shows RealSynCol’s high realism and variability significantly enhance generalization performance on clinical images for depth and pose estimation tasks.
Conclusion: RealSynCol is a powerful synthetic dataset that enables development of robust deep learning algorithms for endoscopic diagnosis by providing realistic training data with comprehensive ground truth.
Abstract: Deep learning has the potential to improve colonoscopy by enabling 3D reconstruction of the colon, providing a comprehensive view of mucosal surfaces and lesions, and facilitating the identification of unexplored areas. However, the development of robust methods is limited by the scarcity of large-scale ground truth data. We propose RealSynCol, a highly realistic synthetic dataset designed to replicate the endoscopic environment. Colon geometries extracted from 10 CT scans were imported into a virtual environment that closely mimics intraoperative conditions and rendered with realistic vascular textures. The resulting dataset comprises 28,130 frames, paired with ground truth depth maps, optical flow, 3D meshes, and camera trajectories. A benchmark study was conducted to evaluate the available synthetic colon datasets for the tasks of depth and pose estimation. Results demonstrate that the high realism and variability of RealSynCol significantly enhance generalization performance on clinical images, proving it to be a powerful tool for developing deep learning algorithms to support endoscopic diagnosis.
[344] Understanding and Optimizing Attention-Based Sparse Matching for Diverse Local Features
Qiang Wang
Main category: cs.CV
TL;DR: LightGlue revisited: detector choice matters more than descriptors for transformer-based image matching; fine-tuning with diverse detectors creates universal matcher
Details
Motivation: To improve transformer-based sparse image matching models by identifying critical overlooked design choices and understanding the relative importance of detectors vs descriptorsMethod: 1) Identify critical design choice in LightGlue model; 2) Analyze role of detectors vs descriptors in transformer matching; 3) Propose fine-tuning approach using keypoints from diverse detectors to create universal detector-agnostic model
Result: Resulting universal model achieves or exceeds accuracy of models specifically trained for novel detectors when used as zero-shot matcher
Conclusion: Detectors are primary cause of performance differences in transformer-based matching; universal detector-agnostic models are feasible and offer deployment advantages
Abstract: We revisit the problem of training attention-based sparse image matching models for various local features. We first identify one critical design choice that has been previously overlooked, which significantly impacts the performance of the LightGlue model. We then investigate the role of detectors and descriptors within the transformer-based matching framework, finding that detectors, rather than descriptors, are often the primary cause for performance difference. Finally, we propose a novel approach to fine-tune existing image matching models using keypoints from a diverse set of detectors, resulting in a universal, detector-agnostic model. When deployed as a zero-shot matcher for novel detectors, the resulting model achieves or exceeds the accuracy of models specifically trained for those features. Our findings offer valuable insights for the deployment of transformer-based matching models and the future design of local features.
[345] Demo-ICL: In-Context Learning for Procedural Video Knowledge Acquisition
Yuhao Dong, Shulin Tian, Shuai Liu, Shuangrui Ding, Yuhang Zang, Xiaoyi Dong, Yuhang Cao, Jiaqi Wang, Ziwei Liu
Main category: cs.CV
TL;DR: A new benchmark and method for demo-driven video in-context learning, where MLLMs learn from video demonstrations to answer questions about target videos.
Details
Motivation: Existing video benchmarks test static knowledge rather than dynamic learning from novel contexts. There's a need to evaluate MLLMs' ability to learn from few video demonstrations.Method: Proposes Demo-ICL-Bench with 1200 instructional YouTube videos and two demonstration types (text summaries and video demonstrations). Develops Demo-ICL model with two-stage training: video-supervised fine-tuning and information-assisted direct preference optimization.
Result: Benchmark proves challenging for state-of-the-art MLLMs. Demo-ICL demonstrates effectiveness in learning from in-context video examples, revealing future research directions.
Conclusion: The work introduces a novel video in-context learning task and benchmark, showing current MLLMs’ limitations and proposing an effective training approach for video understanding.
Abstract: Despite the growing video understanding capabilities of recent Multimodal Large Language Models (MLLMs), existing video benchmarks primarily assess understanding based on models’ static, internal knowledge, rather than their ability to learn and adapt from dynamic, novel contexts from few examples. To bridge this gap, we present Demo-driven Video In-Context Learning, a novel task focused on learning from in-context demonstrations to answer questions about the target videos. Alongside this, we propose Demo-ICL-Bench, a challenging benchmark designed to evaluate demo-driven video in-context learning capabilities. Demo-ICL-Bench is constructed from 1200 instructional YouTube videos with associated questions, from which two types of demonstrations are derived: (i) summarizing video subtitles for text demonstration; and (ii) corresponding instructional videos as video demonstrations. To effectively tackle this new challenge, we develop Demo-ICL, an MLLM with a two-stage training strategy: video-supervised fine-tuning and information-assisted direct preference optimization, jointly enhancing the model’s ability to learn from in-context examples. Extensive experiments with state-of-the-art MLLMs confirm the difficulty of Demo-ICL-Bench, demonstrate the effectiveness of Demo-ICL, and thereby unveil future research directions.
[346] Vista: Scene-Aware Optimization for Streaming Video Question Answering under Post-Hoc Queries
Haocheng Lu, Nan Zhang, Wei Tao, Xiaoyang Qu, Guokuan Li, Jiguang Wan, Jianzong Wang
Main category: cs.CV
TL;DR: Vista is a scene-aware streaming video QA framework that dynamically segments video streams into coherent scenes, compresses them into tokens for efficient GPU storage, and selectively recalls relevant scenes for query answering.
Details
Motivation: Existing MLLMs struggle with streaming video QA due to sequential frame arrival and arbitrary query timing. Fixed-size memory or naive compression approaches suffer from context loss or memory overflow in long-form, real-time scenarios.Method: Three key innovations: (1) scene-aware segmentation - dynamic clustering of frames into coherent scenes; (2) scene-aware compression - compact token representation stored in GPU while full frames offloaded to CPU; (3) scene-aware recall - selective retrieval and reintegration of relevant scenes for query answering.
Result: Extensive experiments on StreamingBench show Vista achieves state-of-the-art performance, establishing a strong baseline for real-world streaming video understanding.
Conclusion: Vista provides an efficient, scalable framework for streaming video QA that enables long-context reasoning without compromising latency or memory efficiency, working seamlessly with various vision-language backbones.
Abstract: Streaming video question answering (Streaming Video QA) poses distinct challenges for multimodal large language models (MLLMs), as video frames arrive sequentially and user queries can be issued at arbitrary time points. Existing solutions relying on fixed-size memory or naive compression often suffer from context loss or memory overflow, limiting their effectiveness in long-form, real-time scenarios. We present Vista, a novel framework for scene-aware streaming video QA that enables efficient and scalable reasoning over continuous video streams. The innovation of Vista can be summarized in three aspects: (1) scene-aware segmentation, where Vista dynamically clusters incoming frames into temporally and visually coherent scene units; (2) scene-aware compression, where each scene is compressed into a compact token representation and stored in GPU memory for efficient index-based retrieval, while full-resolution frames are offloaded to CPU memory; and (3) scene-aware recall, where relevant scenes are selectively recalled and reintegrated into the model input upon receiving a query, enabling both efficiency and completeness. Vista is model-agnostic and integrates seamlessly with a variety of vision-language backbones, enabling long-context reasoning without compromising latency or memory efficiency. Extensive experiments on StreamingBench demonstrate that Vista achieves state-of-the-art performance, establishing a strong baseline for real-world streaming video understanding.
[347] TriC-Motion: Tri-Domain Causal Modeling Grounded Text-to-Motion Generation
Yiyang Cao, Yunze Deng, Ziyu Lin, Bin Feng, Xinggang Wang, Wenyu Liu, Dandan Zheng, Jingdong Chen
Main category: cs.CV
TL;DR: TriC-Motion: A diffusion-based text-to-motion generation framework that integrates spatial, temporal, and frequency domain modeling with causal intervention for superior motion generation quality.
Details
Motivation: Current text-to-motion methods lack unified joint optimization across spatial, temporal, and frequency domains, leading to suboptimal generation quality. Motion-irrelevant noise cues are entangled with positive features, causing motion distortion.Method: Proposes Tri-Domain Causal Text-to-Motion Generation (TriC-Motion) with three core modules: Temporal Motion Encoding, Spatial Topology Modeling, and Hybrid Frequency Analysis. Includes Score-guided Tri-domain Fusion for integration and Causality-based Counterfactual Motion Disentangler to eliminate noise.
Result: Achieves state-of-the-art performance with R@1 of 0.612 on HumanML3D dataset, demonstrating superior generation of high-fidelity, coherent, diverse, and text-aligned motion sequences.
Conclusion: TriC-Motion successfully addresses limitations of existing methods by providing unified tri-domain modeling with causal intervention, resulting in significantly improved text-to-motion generation quality.
Abstract: Text-to-motion generation, a rapidly evolving field in computer vision, aims to produce realistic and text-aligned motion sequences. Current methods primarily focus on spatial-temporal modeling or independent frequency domain analysis, lacking a unified framework for joint optimization across spatial, temporal, and frequency domains. This limitation hinders the model’s ability to leverage information from all domains simultaneously, leading to suboptimal generation quality. Additionally, in motion generation frameworks, motion-irrelevant cues caused by noise are often entangled with features that contribute positively to generation, thereby leading to motion distortion. To address these issues, we propose Tri-Domain Causal Text-to-Motion Generation (TriC-Motion), a novel diffusion-based framework integrating spatial-temporal-frequency-domain modeling with causal intervention. TriC-Motion includes three core modeling modules for domain-specific modeling, namely Temporal Motion Encoding, Spatial Topology Modeling, and Hybrid Frequency Analysis. After comprehensive modeling, a Score-guided Tri-domain Fusion module integrates valuable information from the triple domains, simultaneously ensuring temporal consistency, spatial topology, motion trends, and dynamics. Moreover, the Causality-based Counterfactual Motion Disentangler is meticulously designed to expose motion-irrelevant cues to eliminate noise, disentangling the real modeling contributions of each domain for superior generation. Extensive experimental results validate that TriC-Motion achieves superior performance compared to state-of-the-art methods, attaining an outstanding R@1 of 0.612 on the HumanML3D dataset. These results demonstrate its capability to generate high-fidelity, coherent, diverse, and text-aligned motion sequences. Code is available at: https://caoyiyang1105.github.io/TriC-Motion/.
[348] Gesture Matters: Pedestrian Gesture Recognition for AVs Through Skeleton Pose Evaluation
Alif Rizqullah Mahdi, Mahdi Rezaei, Natasha Merat
Main category: cs.CV
TL;DR: A gesture classification framework using 2D pose estimation to interpret pedestrian gestures for autonomous vehicles, achieving 87% accuracy on four gesture classes.
Details
Motivation: Gestures are crucial for non-verbal communication in traffic, especially when formal rules are insufficient. Autonomous vehicles struggle to interpret pedestrian gestures, creating safety and interaction challenges that need to be addressed.Method: Uses 2D pose estimation on real-world video sequences from WIVW dataset. Categorizes gestures into four classes (Stop, Go, Thank & Greet, No Gesture) and extracts 76 static and dynamic features from normalized keypoints, focusing on hand position and movement velocity.
Result: Achieved 87% classification accuracy, with hand position and movement velocity identified as particularly discriminative features for distinguishing between gesture classes.
Conclusion: The framework improves autonomous vehicle perceptual capabilities and contributes to understanding pedestrian behavior in traffic contexts through effective gesture interpretation.
Abstract: Gestures are a key component of non-verbal communication in traffic, often helping pedestrian-to-driver interactions when formal traffic rules may be insufficient. This problem becomes more apparent when autonomous vehicles (AVs) struggle to interpret such gestures. In this study, we present a gesture classification framework using 2D pose estimation applied to real-world video sequences from the WIVW dataset. We categorise gestures into four primary classes (Stop, Go, Thank & Greet, and No Gesture) and extract 76 static and dynamic features from normalised keypoints. Our analysis demonstrates that hand position and movement velocity are especially discriminative in distinguishing between gesture classes, achieving a classification accuracy score of 87%. These findings not only improve the perceptual capabilities of AV systems but also contribute to the broader understanding of pedestrian behaviour in traffic contexts.
[349] Enhanced Food Category Recognition under Illumination-Induced Domain Shift
Keonvin Park, Aditya Pal, Jin Hong Mok
Main category: cs.CV
TL;DR: Investigates illumination-induced domain shift in multi-class food recognition, showing accuracy degradation under cross-dataset evaluation and proposing illumination-aware augmentation for improved robustness.
Details
Motivation: Real-world food recognition systems (like conveyor-belt inspection) are sensitive to domain shifts from illumination changes. Existing works are limited to single food categories or controlled settings, and most food datasets lack explicit illumination annotations.Method: Uses Food-101 and Fruits-360 datasets to demonstrate cross-dataset accuracy degradation. Constructs synthetic illumination-augmented datasets by varying light temperature and intensity for controlled robustness analysis. Evaluates cross-dataset transfer learning and domain generalization, focusing on illumination-sensitive categories like apple-based classes.
Result: Shows substantial accuracy degradation under cross-dataset evaluation due to mismatched visual conditions. Illumination-aware augmentation significantly improves recognition robustness under domain shift while preserving real-time performance.
Conclusion: Highlights the importance of illumination robustness for deploying reliable food recognition systems in real-world inspection scenarios. Provides practical insights through illumination-aware augmentation techniques.
Abstract: Visual food recognition systems deployed in real-world environments, such as automated conveyor-belt inspection, are highly sensitive to domain shifts caused by illumination changes. While recent studies have shown that lighting variations can significantly distort food perception by both humans and AI, existing works are often limited to single food categories or controlled settings, and most public food datasets lack explicit illumination annotations. In this work, we investigate illumination-induced domain shift in multi-class food category recognition using two widely adopted datasets, Food-101 and Fruits-360. We demonstrate substantial accuracy degradation under cross-dataset evaluation due to mismatched visual conditions. To address this challenge, we construct synthetic illumination-augmented datasets by systematically varying light temperature and intensity, enabling controlled robustness analysis without additional labels. We further evaluate cross-dataset transfer learning and domain generalization, with a focus on illumination-sensitive target categories such as apple-based classes. Experimental results show that illumination-aware augmentation significantly improves recognition robustness under domain shift while preserving real-time performance. Our findings highlight the importance of illumination robustness and provide practical insights for deploying reliable food recognition systems in real-world inspection scenarios.
[350] Are Vision Foundation Models Foundational for Electron Microscopy Image Segmentation?
Caterina Fuster-Barceló, Virginie Uhlmann
Main category: cs.CV
TL;DR: Vision foundation models (VFMs) like DINOv2/v3 and OpenCLIP show good mitochondria segmentation performance within single EM datasets but fail to generalize across heterogeneous microscopy datasets, revealing persistent domain mismatch despite visual similarity.
Details
Motivation: To investigate whether latent representations from vision foundation models are general enough for effective transfer across heterogeneous biomedical microscopy datasets, specifically for mitochondria segmentation in electron microscopy images.Method: Used two public EM datasets (Lucchi++ and VNC) with three VFMs (DINOv2, DINOv3, OpenCLIP). Evaluated two adaptation regimes: frozen-backbone with lightweight segmentation head, and parameter-efficient fine-tuning via LoRA. Analyzed latent spaces with PCA, Fréchet Dinov2 distance, and linear probes.
Result: Single-dataset training yields good segmentation performance with LoRA improving in-domain results. Multi-dataset training causes severe performance degradation for all models, with minimal gains from PEFT. Analysis reveals pronounced domain mismatch between EM datasets despite visual similarity.
Conclusion: VFMs can deliver competitive EM segmentation within single domains with lightweight adaptation, but current PEFT strategies are insufficient for robust cross-dataset generalization without additional domain-alignment mechanisms.
Abstract: Although vision foundation models (VFMs) are increasingly reused for biomedical image analysis, it remains unclear whether the latent representations they provide are general enough to support effective transfer and reuse across heterogeneous microscopy image datasets. Here, we study this question for the problem of mitochondria segmentation in electron microscopy (EM) images, using two popular public EM datasets (Lucchi++ and VNC) and three recent representative VFMs (DINOv2, DINOv3, and OpenCLIP). We evaluate two practical model adaptation regimes: a frozen-backbone setting in which only a lightweight segmentation head is trained on top of the VFM, and parameter-efficient fine-tuning (PEFT) via Low-Rank Adaptation (LoRA) in which the VFM is fine-tuned in a targeted manner to a specific dataset. Across all backbones, we observe that training on a single EM dataset yields good segmentation performance (quantified as foreground Intersection-over-Union), and that LoRA consistently improves in-domain performance. In contrast, training on multiple EM datasets leads to severe performance degradation for all models considered, with only marginal gains from PEFT. Exploration of the latent representation space through various techniques (PCA, Fréchet Dinov2 distance, and linear probes) reveals a pronounced and persistent domain mismatch between the two considered EM datasets in spite of their visual similarity, which is consistent with the observed failure of paired training. These results suggest that, while VFMs can deliver competitive results for EM segmentation within a single domain under lightweight adaptation, current PEFT strategies are insufficient to obtain a single robust model across heterogeneous EM datasets without additional domain-alignment mechanisms.
[351] GeoFocus: Blending Efficient Global-to-Local Perception for Multimodal Geometry Problem-Solving
Linger Deng, Yuliang Liu, Wenwen Yu, Zujia Zhang, Jianzhong Ju, Zhenbo Luo, Xiang Bai
Main category: cs.CV
TL;DR: GeoFocus is a novel framework for geometry problem-solving in multimodal models, featuring Critical Local Perceptor for local structure analysis and VertexLang for global topology encoding, achieving state-of-the-art performance on geometry benchmarks.
Details
Motivation: Geometry problem-solving remains challenging for Large Multimodal Models (LMMs) as it requires both global shape recognition and attention to intricate local relationships based on geometric theory. Current approaches lack sufficient focus on critical local structures and efficient global topology encoding.Method: GeoFocus comprises two core modules: 1) Critical Local Perceptor - automatically identifies and emphasizes critical local structures (angles, parallel lines, distances) using thirteen theory-based perception templates; 2) VertexLang - a compact topology formal language that encodes global figures through vertex coordinates and connectivity relations, replacing bulky code-based encodings.
Result: GeoFocus achieves 4.7% accuracy improvement over leading specialized models on Geo3K, GeoQA, and FormalGeo7K benchmarks. It boosts critical local feature coverage by 61% compared to previous methods, reduces global perception training time by 20%, and demonstrates superior robustness in MATHVERSE under diverse visual conditions.
Conclusion: GeoFocus effectively addresses geometry problem-solving challenges in LMMs by combining enhanced local structure perception with efficient global topology encoding, setting new state-of-the-art performance on multiple geometry benchmarks.
Abstract: Geometry problem-solving remains a significant challenge for Large Multimodal Models (LMMs), requiring not only global shape recognition but also attention to intricate local relationships related to geometric theory. To address this, we propose GeoFocus, a novel framework comprising two core modules. 1) Critical Local Perceptor, which automatically identifies and emphasizes critical local structure (e.g., angles, parallel lines, comparative distances) through thirteen theory-based perception templates, boosting critical local feature coverage by 61% compared to previous methods. 2) VertexLang, a compact topology formal language, encodes global figures through vertex coordinates and connectivity relations. By replacing bulky code-based encodings, VertexLang reduces global perception training time by 20% while improving topology recognition accuracy. When evaluated in Geo3K, GeoQA, and FormalGeo7K, GeoFocus achieves a 4.7% accuracy improvement over leading specialized models and demonstrates superior robustness in MATHVERSE under diverse visual conditions. Project Page – https://github.com/dle666/GeoFocus
[352] Automatic regularization parameter choice for tomography using a double model approach
Chuyang Wu, Samuli Siltanen
Main category: cs.CV
TL;DR: Novel automatic regularization parameter selection method for X-ray tomography using two computational grids and feedback control
Details
Motivation: X-ray tomography reconstruction is ill-posed with limited data, requiring regularization. Traditional methods need manual parameter tuning, which is challenging and subjective.Method: Uses two distinct computational discretizations of the same problem. A feedback control algorithm dynamically adjusts regularization strength, driving iterative reconstruction toward smallest parameter that yields sufficient similarity between reconstructions on the two grids.
Result: Demonstrated effectiveness using real tomographic data, showing the method can automatically select appropriate regularization parameters.
Conclusion: The proposed approach provides an automatic, data-driven method for regularization parameter selection in X-ray tomography, eliminating need for manual tuning.
Abstract: Image reconstruction in X-ray tomography is an ill-posed inverse problem, particularly with limited available data. Regularization is thus essential, but its effectiveness hinges on the choice of a regularization parameter that balances data fidelity against a priori information. We present a novel method for automatic parameter selection based on the use of two distinct computational discretizations of the same problem. A feedback control algorithm dynamically adjusts the regularization strength, driving an iterative reconstruction toward the smallest parameter that yields sufficient similarity between reconstructions on the two grids. The effectiveness of the proposed approach is demonstrated using real tomographic data.
[353] Thegra: Graph-based SLAM for Thermal Imagery
Anastasiia Kornilova, Ivan Moskalenko, Arabella Gromova, Gonzalo Ferrer, Alexander Menshchikov
Main category: cs.CV
TL;DR: A thermal imaging SLAM system using learned features (SuperPoint/LightGlue) from visible-spectrum data for cross-domain generalization, with preprocessing and confidence-weighted graph optimization for robustness in low-texture thermal environments.
Details
Motivation: Thermal imaging enables SLAM in visually degraded environments (low light, smoke, adverse weather), but thermal imagery suffers from low texture, low contrast, and high noise, making feature-based SLAM challenging. There's a need for robust thermal SLAM without requiring large thermal datasets for training.Method: Proposes sparse monocular graph-based SLAM for thermal imagery using learned features (SuperPoint detector and LightGlue matcher) trained on visible-spectrum data. Includes preprocessing pipeline to enhance thermal input suitability, modifies SLAM modules to handle sparse/outlier-prone matches, and incorporates SuperPoint keypoint confidence scores into confidence-weighted factor graph optimization.
Result: Evaluation on public thermal datasets shows reliable performance without dataset-specific training or fine-tuning feature detectors, addressing the scarcity of quality thermal data.
Conclusion: The system demonstrates effective cross-domain generalization of learned features from visible to thermal spectrum, enabling robust thermal SLAM without requiring thermal-specific training data.
Abstract: Thermal imaging provides a practical sensing modality for visual SLAM in visually degraded environments such as low illumination, smoke, or adverse weather. However, thermal imagery often exhibits low texture, low contrast, and high noise, complicating feature-based SLAM. In this work, we propose a sparse monocular graph-based SLAM system for thermal imagery that leverages general-purpose learned features – the SuperPoint detector and LightGlue matcher, trained on large-scale visible-spectrum data to improve cross-domain generalization. To adapt these components to thermal data, we introduce a preprocessing pipeline to enhance input suitability and modify core SLAM modules to handle sparse and outlier-prone feature matches. We further incorporate keypoint confidence scores from SuperPoint into a confidence-weighted factor graph to improve estimation robustness. Evaluations on public thermal datasets demonstrate that the proposed system achieves reliable performance without requiring dataset-specific training or fine-tuning a desired feature detector, given the scarcity of quality thermal data. Code will be made available upon publication.
[354] TIBR4D: Tracing-Guided Iterative Boundary Refinement for Efficient 4D Gaussian Segmentation
He Wu, Xia Yan, Yanghui Xu, Liegang Xia, Jiazhou Chen
Main category: cs.CV
TL;DR: TIBR4D: A learning-free 4D Gaussian segmentation framework that lifts video segmentation masks to 4D spaces using two-stage iterative boundary refinement for dynamic scenes.
Details
Motivation: Object-level segmentation in dynamic 4D Gaussian scenes is challenging due to complex motion, occlusions, and ambiguous boundaries. Existing methods struggle with these issues, particularly in preserving object structure completeness and handling boundary uncertainty.Method: Two-stage iterative boundary refinement: 1) Iterative Gaussian Instance Tracing (IGIT) at temporal segment level refines Gaussian-to-instance probabilities through iterative tracing to handle occlusions; 2) Gaussian Rendering Range Control (RCC) suppresses uncertain Gaussians near boundaries while retaining core contributions. Includes temporal segmentation merging strategy for identity consistency vs. dynamic awareness balance.
Result: Experiments on HyperNeRF and Neu3D show the method produces accurate object Gaussian point clouds with clearer boundaries and higher efficiency compared to state-of-the-art methods.
Conclusion: TIBR4D provides an efficient learning-free solution for 4D Gaussian segmentation that effectively handles complex motion, occlusions, and boundary ambiguity while maintaining object structure completeness.
Abstract: Object-level segmentation in dynamic 4D Gaussian scenes remains challenging due to complex motion, occlusions, and ambiguous boundaries. In this paper, we present an efficient learning-free 4D Gaussian segmentation framework that lifts video segmentation masks to 4D spaces, whose core is a two-stage iterative boundary refinement, TIBR4D. The first stage is an Iterative Gaussian Instance Tracing (IGIT) at the temporal segment level. It progressively refines Gaussian-to-instance probabilities through iterative tracing, and extracts corresponding Gaussian point clouds that better handle occlusions and preserve completeness of object structures compared to existing one-shot threshold-based methods. The second stage is a frame-wise Gaussian Rendering Range Control (RCC) via suppressing highly uncertain Gaussians near object boundaries while retaining their core contributions for more accurate boundaries. Furthermore, a temporal segmentation merging strategy is proposed for IGIT to balance identity consistency and dynamic awareness. Longer segments enforce stronger multi-frame constraints for stable identities, while shorter segments allow identity changes to be captured promptly. Experiments on HyperNeRF and Neu3D demonstrate that our method produces accurate object Gaussian point clouds with clearer boundaries and higher efficiency compared to SOTA methods.
[355] FLAG-4D: Flow-Guided Local-Global Dual-Deformation Model for 4D Reconstruction
Guan Yuan Tan, Ngoc Tuan Vu, Arghya Pal, Sailaja Rajanala, Raphael Phan C. -W., Mettu Srinivas, Chee-Ming Ting
Main category: cs.CV
TL;DR: FLAG-4D is a novel framework for dynamic 3D scene reconstruction using dual-deformation networks to model how 3D Gaussian primitives evolve through space and time, achieving higher fidelity and temporal coherence than existing methods.
Details
Motivation: Existing methods for dynamic scene reconstruction typically use single MLPs to model temporal deformations, which struggle to capture complex point motions and fine-grained dynamic details consistently over time, especially from sparse input views.Method: FLAG-4D employs a dual-deformation network with an Instantaneous Deformation Network (IDN) for fine-grained local deformations and a Global Motion Network (GMN) for long-range dynamics, refined through mutual learning. It incorporates dense motion features from pretrained optical flow and uses deformation-guided attention to align flow information with evolving 3D Gaussians.
Result: Extensive experiments demonstrate that FLAG-4D achieves higher-fidelity and more temporally coherent reconstructions with finer detail preservation than state-of-the-art methods.
Conclusion: FLAG-4D successfully overcomes limitations of existing dynamic scene reconstruction methods by using dual-deformation networks and motion feature integration, enabling more accurate and temporally smooth modeling of complex 3D scene dynamics.
Abstract: We introduce FLAG-4D, a novel framework for generating novel views of dynamic scenes by reconstructing how 3D Gaussian primitives evolve through space and time. Existing methods typically rely on a single Multilayer Perceptron (MLP) to model temporal deformations, and they often struggle to capture complex point motions and fine-grained dynamic details consistently over time, especially from sparse input views. Our approach, FLAG-4D, overcomes this by employing a dual-deformation network that dynamically warps a canonical set of 3D Gaussians over time into new positions and anisotropic shapes. This dual-deformation network consists of an Instantaneous Deformation Network (IDN) for modeling fine-grained, local deformations and a Global Motion Network (GMN) for capturing long-range dynamics, refined through mutual learning. To ensure these deformations are both accurate and temporally smooth, FLAG-4D incorporates dense motion features from a pretrained optical flow backbone. We fuse these motion cues from adjacent timeframes and use a deformation-guided attention mechanism to align this flow information with the current state of each evolving 3D Gaussian. Extensive experiments demonstrate that FLAG-4D achieves higher-fidelity and more temporally coherent reconstructions with finer detail preservation than state-of-the-art methods.
[356] SemiNFT: Learning to Transfer Presets from Imitation to Appreciation via Hybrid-Sample Reinforcement Learning
Melany Yang, Yuhang Yu, Diwang Weng, Jinwei Chen, Wei Dong
Main category: cs.CV
TL;DR: SemiNFT is a Diffusion Transformer-based color retouching framework that learns through imitation then reinforcement learning, achieving sophisticated aesthetic comprehension beyond statistical matching.
Details
Motivation: Manual color retouching requires specialized expertise, making it inaccessible to non-experts. Reference-based methods often fail to understand semantic context or human aesthetics, performing only global color mappings from pixel statistics.Method: SemiNFT uses a Diffusion Transformer (DiT) framework that follows human artistic training: first learns from paired triplets for structural preservation and color mapping, then advances to reinforcement learning on unpaired data for aesthetic perception. A hybrid online-offline reward mechanism prevents catastrophic forgetting during RL.
Result: Outperforms state-of-the-art methods on preset transfer benchmarks and demonstrates remarkable intelligence in zero-shot tasks like black-and-white photo colorization and cross-domain (anime-to-photo) preset transfer.
Conclusion: SemiNFT transcends simple statistical matching and achieves sophisticated aesthetic comprehension, confirming its ability to understand semantic context and human aesthetics in color retouching.
Abstract: Photorealistic color retouching plays a vital role in visual content creation, yet manual retouching remains inaccessible to non-experts due to its reliance on specialized expertise. Reference-based methods offer a promising alternative by transferring the preset color of a reference image to a source image. However, these approaches often operate as novice learners, performing global color mappings derived from pixel-level statistics, without a true understanding of semantic context or human aesthetics. To address this issue, we propose SemiNFT, a Diffusion Transformer (DiT)-based retouching framework that mirrors the trajectory of human artistic training: beginning with rigid imitation and evolving into intuitive creation. Specifically, SemiNFT is first taught with paired triplets to acquire basic structural preservation and color mapping skills, and then advanced to reinforcement learning (RL) on unpaired data to cultivate nuanced aesthetic perception. Crucially, during the RL stage, to prevent catastrophic forgetting of old skills, we design a hybrid online-offline reward mechanism that anchors aesthetic exploration with structural review. % experiments Extensive experiments show that SemiNFT not only outperforms state-of-the-art methods on standard preset transfer benchmarks but also demonstrates remarkable intelligence in zero-shot tasks, such as black-and-white photo colorization and cross-domain (anime-to-photo) preset transfer. These results confirm that SemiNFT transcends simple statistical matching and achieves a sophisticated level of aesthetic comprehension. Our project can be found at https://melanyyang.github.io/SemiNFT/.
[357] Overview and Comparison of AVS Point Cloud Compression Standard
Wei Gao, Wenxu Gao, Xingming Mu, Changhao Peng, Ge Li
Main category: cs.CV
TL;DR: This paper reviews China’s AVS PCC (Audio Video coding Standard Point Cloud Compression) standard, comparing its technical approaches and performance against other point cloud compression standards like MPEG’s G-PCC and V-PCC.
Details
Motivation: Point clouds are important 3D data representations with applications in immersive media, autonomous driving, and digital heritage, but their large data size creates transmission and storage challenges. Standardization efforts aim to optimize compression for both human and machine perception.Method: The paper reviews the AVS PCC standard from two perspectives: 1) analyzing the related technologies and coding tools adopted in AVS PCC, and 2) conducting performance comparisons with other standards like MPEG’s G-PCC and V-PCC.
Result: The AVS PCC standard incorporates many new coding tools and techniques that differ from other counterpart standards, suggesting unique technical approaches to point cloud compression.
Conclusion: AVS PCC represents China’s standardization effort in point cloud compression with distinct technical features compared to international standards, addressing the growing need for efficient 3D data compression in various applications.
Abstract: Point cloud is a prevalent 3D data representation format with significant application values in immersive media, autonomous driving, digital heritage protection, etc. However, the large data size of point clouds poses challenges to transmission and storage, which influences the wide deployments. Therefore, point cloud compression plays a crucial role in practical applications for both human and machine perception optimization. To this end, the Moving Picture Experts Group (MPEG) has established two standards for point cloud compression, including Geometry-based Point Cloud Compression (G-PCC) and Video-based Point Cloud Compression (V-PCC). In the meantime, the Audio Video coding Standard (AVS) Workgroup of China also have launched and completed the development for its first generation point cloud compression standard, namely AVS PCC. This new standardization effort has adopted many new coding tools and techniques, which are different from the other counterpart standards. This paper reviews the AVS PCC standard from two perspectives, i.e., the related technologies and performance comparisons.
[358] Inspiration Seeds: Learning Non-Literal Visual Combinations for Generative Exploration
Kfir Goldberg, Elad Richardson, Yael Vinker
Main category: cs.CV
TL;DR: Inspiration Seeds is a generative framework for visual ideation that creates diverse compositions from two input images without text prompts, revealing latent relationships between them.
Details
Motivation: Current generative models are optimized for executing precise text prompts but lack support for open-ended visual exploration that precedes idea formation, which designers need when drawing inspiration from loosely connected visual references.Method: Feed-forward framework trained on synthetic triplets of decomposed visual aspects using CLIP Sparse Autoencoders to extract editing directions in CLIP latent space and isolate concept pairs, removing reliance on language.
Result: Produces diverse, visually coherent compositions that reveal latent relationships between input images, enabling fast, intuitive recombination for visual ideation.
Conclusion: The framework shifts image generation from final execution to exploratory ideation, supporting creative work at early, ambiguous stages by enabling visual exploration without text prompts.
Abstract: While generative models have become powerful tools for image synthesis, they are typically optimized for executing carefully crafted textual prompts, offering limited support for the open-ended visual exploration that often precedes idea formation. In contrast, designers frequently draw inspiration from loosely connected visual references, seeking emergent connections that spark new ideas. We propose Inspiration Seeds, a generative framework that shifts image generation from final execution to exploratory ideation. Given two input images, our model produces diverse, visually coherent compositions that reveal latent relationships between inputs, without relying on user-specified text prompts. Our approach is feed-forward, trained on synthetic triplets of decomposed visual aspects derived entirely through visual means: we use CLIP Sparse Autoencoders to extract editing directions in CLIP latent space and isolate concept pairs. By removing the reliance on language and enabling fast, intuitive recombination, our method supports visual ideation at the early and ambiguous stages of creative work.
[359] Improving Reconstruction of Representation Autoencoder
Siyu Liu, Chujie Qin, Hubery Yin, Qixin Yan, Zheng-Peng Duan, Chen Li, Jing Lyu, Chun-Le Guo, Chongyi Li
Main category: cs.CV
TL;DR: LV-RAE is a representation autoencoder that enhances semantic features from vision foundation models with low-level information to improve reconstruction fidelity in latent diffusion models while maintaining semantic alignment.
Details
Motivation: Vision foundation models used as image encoders in latent diffusion models provide good semantic features but lack low-level information like color and texture, leading to poor reconstruction fidelity which limits scaling of LDMs.Method: Proposes LV-RAE that augments semantic features with missing low-level information; addresses decoder sensitivity to latent perturbations by fine-tuning decoder for robustness and smoothing generated latents via controlled noise injection.
Result: LV-RAE significantly improves reconstruction fidelity while preserving semantic abstraction and achieving strong generative quality, overcoming the bottleneck in scaling latent diffusion models.
Conclusion: The proposed approach successfully addresses the low-level information deficiency in vision foundation model features, enabling high-fidelity reconstruction and better generation quality in latent diffusion models.
Abstract: Recent work leverages Vision Foundation Models as image encoders to boost the generative performance of latent diffusion models (LDMs), as their semantic feature distributions are easy to learn. However, such semantic features often lack low-level information (\eg, color and texture), leading to degraded reconstruction fidelity, which has emerged as a primary bottleneck in further scaling LDMs. To address this limitation, we propose LV-RAE, a representation autoencoder that augments semantic features with missing low-level information, enabling high-fidelity reconstruction while remaining highly aligned with the semantic distribution. We further observe that the resulting high-dimensional, information-rich latent make decoders sensitive to latent perturbations, causing severe artifacts when decoding generated latent and consequently degrading generation quality. Our analysis suggests that this sensitivity primarily stems from excessive decoder responses along directions off the data manifold. Building on these insights, we propose fine-tuning the decoder to increase its robustness and smoothing the generated latent via controlled noise injection, thereby enhancing generation quality. Experiments demonstrate that LV-RAE significantly improves reconstruction fidelity while preserving the semantic abstraction and achieving strong generative quality. Our code is available at https://github.com/modyu-liu/LVRAE.
[360] Revisiting [CLS] and Patch Token Interaction in Vision Transformers
Alexis Marouani, Oriane Siméoni, Hervé Jégou, Piotr Bojanowski, Huy V. Vo
Main category: cs.CV
TL;DR: Specialized processing paths for class and patch tokens in Vision Transformers improve dense prediction performance without computational overhead
Details
Motivation: Vision Transformers process class tokens and patch tokens identically despite their different functions, creating friction between global and local feature learning that limits dense prediction performanceMethod: Analyze interactions between class and patch tokens, discover normalization layers create implicit differentiation, then propose specialized processing paths that disentangle computational flow for different token types, particularly in normalization layers and early query-key-value projections
Result: Significant improvements in dense prediction tasks (over 2 mIoU points gain in segmentation), maintains classification accuracy, only 8% parameter increase with no computational overhead
Conclusion: Targeted specialization of processing paths for different token types in Vision Transformers enhances representation quality for dense prediction while preserving efficiency
Abstract: Vision Transformers have emerged as powerful, scalable and versatile representation learners. To capture both global and local features, a learnable [CLS] class token is typically prepended to the input sequence of patch tokens. Despite their distinct nature, both token types are processed identically throughout the model. In this work, we investigate the friction between global and local feature learning under different pre-training strategies by analyzing the interactions between class and patch tokens. Our analysis reveals that standard normalization layers introduce an implicit differentiation between these token types. Building on this insight, we propose specialized processing paths that selectively disentangle the computational flow of class and patch tokens, particularly within normalization layers and early query-key-value projections. This targeted specialization leads to significantly improved patch representation quality for dense prediction tasks. Our experiments demonstrate segmentation performance gains of over 2 mIoU points on standard benchmarks, while maintaining strong classification accuracy. The proposed modifications introduce only an 8% increase in parameters, with no additional computational overhead. Through comprehensive ablations, we provide insights into which architectural components benefit most from specialization and how our approach generalizes across model scales and learning frameworks.
[361] Deep Learning-Based Fixation Type Prediction for Quality Assurance in Digital Pathology
Oskar Thaeter, Tanja Niedermair, Johannes Raffler, Ralf Huss, Peter J. Schüffler
Main category: cs.CV
TL;DR: Deep learning model predicts pathology slide fixation types (FFPE vs frozen section) using low-resolution thumbnail images instead of full-resolution scans, enabling 400× faster processing for high-throughput quality control.
Details
Motivation: Manual annotation of fixation types in pathology slides is error-prone and existing verification methods require full-resolution whole-slide images, limiting scalability for high-throughput quality control in pathology laboratories.Method: Developed a deep learning model that predicts fixation types using low-resolution, pre-scan thumbnail images. Trained on 1,200 WSIs from TUM Institute of Pathology and evaluated on multiple datasets including TCGA (8,800 slides), Augsburg (695 slides), and Regensburg (202 slides) from different scanners.
Result: Model achieves AUROC of 0.88 on TCGA dataset, outperforming comparable pre-scan methods by 4.8%. Achieves AUROCs of 0.72 on Regensburg and Augsburg datasets, showing challenges with scanner-induced domain shifts. Processes each slide in 21 ms, 400× faster than existing high-magnification methods.
Conclusion: The approach provides an efficient solution for detecting labeling errors without high-magnification scans, offering a valuable tool for quality control in high-throughput pathology workflows. Future work will improve generalization to additional scanner types and extend to other low-resolution slide annotations.
Abstract: Accurate annotation of fixation type is a critical step in slide preparation for pathology laboratories. However, this manual process is prone to errors, impacting downstream analyses and diagnostic accuracy. Existing methods for verifying formalin-fixed, paraffin-embedded (FFPE), and frozen section (FS) fixation types typically require full-resolution whole-slide images (WSIs), limiting scalability for high-throughput quality control. We propose a deep-learning model to predict fixation types using low-resolution, pre-scan thumbnail images. The model was trained on WSIs from the TUM Institute of Pathology (n=1,200, Leica GT450DX) and evaluated on a class-balanced subset of The Cancer Genome Atlas dataset (TCGA, n=8,800, Leica AT2), as well as on class-balanced datasets from Augsburg (n=695 [392 FFPE, 303 FS], Philips UFS) and Regensburg (n=202, 3DHISTECH P1000). Our model achieves an AUROC of 0.88 on TCGA, outperforming comparable pre-scan methods by 4.8%. It also achieves AUROCs of 0.72 on Regensburg and Augsburg slides, underscoring challenges related to scanner-induced domain shifts. Furthermore, the model processes each slide in 21 ms, $400\times$ faster than existing high-magnification, full-resolution methods, enabling rapid, high-throughput processing. This approach provides an efficient solution for detecting labelling errors without relying on high-magnification scans, offering a valuable tool for quality control in high-throughput pathology workflows. Future work will improve and evaluate the model’s generalisation to additional scanner types. Our findings suggest that this method can increase accuracy and efficiency in digital pathology workflows and may be extended to other low-resolution slide annotations.
[362] WiFlow: A Lightweight WiFi-based Continuous Human Pose Estimation Network with Spatio-Temporal Feature Decoupling
Yi Dao, Lankai Zhang, Hao Liu, Haiwei Zhang, Wenbo Wang
Main category: cs.CV
TL;DR: WiFlow: A WiFi-based continuous human pose estimation framework using encoder-decoder architecture with spatio-temporal feature extraction and axial attention for structural dependencies.
Details
Motivation: Human pose estimation is crucial for IoT applications, but WiFi-based methods struggle with continuous motion and high computational overhead. Vision-based approaches treat CSI as images, losing sequential signal structure.Method: Encoder-decoder architecture: encoder uses temporal and asymmetric convolutions to capture spatio-temporal CSI features while preserving sequential structure, refines keypoint features via axial attention for structural dependencies, decoder maps to keypoint coordinates.
Result: Achieves PCK@20 of 97.00% and PCK@50 of 99.48% with mean per-joint error of 0.008m on 360,000 CSI-pose samples from 5 subjects performing 8 daily activities. Only 4.82M parameters, reducing computational cost.
Conclusion: WiFlow establishes new performance baseline for practical WiFi-based human pose estimation with reduced model complexity, enabling continuous motion tracking for IoT applications.
Abstract: Human pose estimation is fundamental to intelligent perception in the Internet of Things (IoT), enabling applications ranging from smart healthcare to human-computer interaction. While WiFi-based methods have gained traction, they often struggle with continuous motion and high computational overhead. This work presents WiFlow, a novel framework for continuous human pose estimation using WiFi signals. Unlike vision-based approaches such as two-dimensional deep residual networks that treat Channel State Information (CSI) as images, WiFlow employs an encoder-decoder architecture. The encoder captures spatio-temporal features of CSI using temporal and asymmetric convolutions, preserving the original sequential structure of signals. It then refines keypoint features of human bodies to be tracked and capture their structural dependencies via axial attention. The decoder subsequently maps the encoded high-dimensional features into keypoint coordinates. Trained on a self-collected dataset of 360,000 synchronized CSI-pose samples from 5 subjects performing continuous sequences of 8 daily activities, WiFlow achieves a Percentage of Correct Keypoints (PCK) of 97.00% at a threshold of 20% (PCK@20) and 99.48% at PCK@50, with a mean per-joint position error of 0.008m. With only 4.82M parameters, WiFlow significantly reduces model complexity and computational cost, establishing a new performance baseline for practical WiFi-based human pose estimation. Our code and datasets are available at https://github.com/DY2434/WiFlow-WiFi-Pose-Estimation-with-Spatio-Temporal-Decoupling.git.
[363] A Machine Learning accelerated geophysical fluid solver
Yang Bai
Main category: cs.CV
TL;DR: The paper explores applying machine learning to solve PDEs using data-driven discretization methods, implementing neural networks for shallow water and Euler equations that outperform traditional solvers.
Details
Motivation: To address the challenge of applying machine learning to mathematically constrained domains like PDE solving, particularly improving accuracy and stability of low-resolution simulations compared to traditional finite difference/volume methods.Method: Implemented classic solvers for shallow water and Euler equations, then proposed four different deep neural network architectures for ML-based PDE solvers using data-driven discretization that predicts coefficients of quasi-linear stencils.
Result: The classic solvers performed much better than Pyclaw solver, and two of the four proposed neural network approaches produced satisfactory solutions for the PDE problems.
Conclusion: Data-driven discretization methods with neural networks show promise for accelerating and improving PDE solvers on structured grids, combining ML benefits with traditional numerical scheme advantages like conservation laws.
Abstract: Machine learning methods have been successful in many areas, like image classification and natural language processing. However, it still needs to be determined how to apply ML to areas with mathematical constraints, like solving PDEs. Among various approaches to applying ML techniques to solving PDEs, the data-driven discretization method presents a promising way of accelerating and improving existing PDE solver on structured grids where it predicts the coefficients of quasi-linear stencils for computing values or derivatives of a function at given positions. It can improve the accuracy and stability of low-resolution simulation compared with using traditional finite difference or finite volume schemes. Meanwhile, it can also benefit from traditional numerical schemes like achieving conservation law by adapting finite volume type formulations. In this thesis, we have implemented the shallow water equation and Euler equation classic solver under a different framework. Experiments show that our classic solver performs much better than the Pyclaw solver. Then we propose four different deep neural networks for the ML-based solver. The results indicate that two of these approaches could output satisfactory solutions.
[364] ALIVE: Animate Your World with Lifelike Audio-Video Generation
Ying Guo, Qijun Gan, Yifu Zhang, Jinlai Liu, Yifei Hu, Pan Xie, Dongjun Qian, Yu Zhang, Ruiqi Li, Yuqi Zhang, Ruibiao Lu, Xiaofeng Mei, Bo Han, Xiang Yin, Bingyue Peng, Zehuan Yuan
Main category: cs.CV
TL;DR: ALIVE adapts pretrained T2V models for Sora-style audio-video generation and animation, achieving state-of-the-art performance through architectural innovations and high-quality data
Details
Motivation: Video generation is evolving toward unified audio-video generation, but existing T2V models lack audio capabilities. The paper aims to adapt pretrained T2V models to achieve Sora-style audio-video generation and animation capabilities.Method: Augments MMDiT architecture with joint audio-video branch featuring TA-CrossAttn for temporally-aligned cross-modal fusion and UniTemp-RoPE for precise audio-visual alignment. Uses comprehensive data pipeline for high-quality finetuning data collection and introduces new benchmark for evaluation.
Result: ALIVE demonstrates outstanding performance after training on million-level high-quality data, consistently outperforming open-source models and matching or surpassing state-of-the-art commercial solutions.
Conclusion: ALIVE successfully enables audio-video generation capabilities in T2V models, providing detailed recipes and benchmarks to help the community develop such models more efficiently.
Abstract: Video generation is rapidly evolving towards unified audio-video generation. In this paper, we present ALIVE, a generation model that adapts a pretrained Text-to-Video (T2V) model to Sora-style audio-video generation and animation. In particular, the model unlocks the Text-to-Video&Audio (T2VA) and Reference-to-Video&Audio (animation) capabilities compared to the T2V foundation models. To support the audio-visual synchronization and reference animation, we augment the popular MMDiT architecture with a joint audio-video branch which includes TA-CrossAttn for temporally-aligned cross-modal fusion and UniTemp-RoPE for precise audio-visual alignment. Meanwhile, a comprehensive data pipeline consisting of audio-video captioning, quality control, etc., is carefully designed to collect high-quality finetuning data. Additionally, we introduce a new benchmark to perform a comprehensive model test and comparison. After continue pretraining and finetuning on million-level high-quality data, ALIVE demonstrates outstanding performance, consistently outperforming open-source models and matching or surpassing state-of-the-art commercial solutions. With detailed recipes and benchmarks, we hope ALIVE helps the community develop audio-video generation models more efficiently. Official page: https://github.com/FoundationVision/Alive.
[365] OneVision-Encoder: Codec-Aligned Sparsity as a Foundational Principle for Multimodal Intelligence
Feilong Tang, Xiang An, Yunyao Yan, Yin Xie, Bin Qin, Kaicheng Yang, Yifei Shen, Yuanhan Zhang, Chunyuan Li, Shikun Feng, Changrui Chen, Huajie Tan, Ming Hu, Manyuan Zhang, Bo Li, Ziyong Feng, Ziwei Liu, Zongyuan Ge, Jiankang Deng
Main category: cs.CV
TL;DR: OneVision-Encoder is a video compression-based vision encoder that focuses computational resources on sparse, information-rich regions using codec-inspired patchification, achieving superior efficiency and performance on multimodal tasks.
Details
Motivation: Current vision architectures waste computation on redundant visual data while ignoring sparse discriminative information. The paper argues that visual understanding requires architectures aligned with information-theoretic principles of video compression, focusing on predictive residuals rather than uniform pixel processing.Method: OneVision-Encoder uses Codec Patchification to focus computation on only 3.1%-25% of regions with high signal entropy. It employs shared 3D RoPE for spatial-temporal reasoning with irregular token layouts and is trained with large-scale cluster discrimination over 1M+ semantic concepts to capture object permanence and motion dynamics.
Result: Outperforms strong vision backbones like Qwen3-ViT and SigLIP2 across 16 image, video, and document understanding benchmarks despite using fewer visual tokens and less pretraining data. Achieves 4.1% average improvement over Qwen3-ViT on video tasks, demonstrating efficiency-accuracy positive correlation.
Conclusion: Codec-aligned patch-level sparsity is a foundational principle for scalable visual generalists. Efficiency and accuracy are positively correlated when architectures align with information-theoretic principles of video compression.
Abstract: Hypothesis. Artificial general intelligence is, at its core, a compression problem. Effective compression demands resonance: deep learning scales best when its architecture aligns with the fundamental structure of the data. These are the fundamental principles. Yet, modern vision architectures have strayed from these truths: visual signals are highly redundant, while discriminative information, the surprise, is sparse. Current models process dense pixel grids uniformly, wasting vast compute on static background rather than focusing on the predictive residuals that define motion and meaning. We argue that to solve visual understanding, we must align our architectures with the information-theoretic principles of video, i.e., Codecs. Method. OneVision-Encoder encodes video by compressing predictive visual structure into semantic meaning. By adopting Codec Patchification, OV-Encoder abandons uniform computation to focus exclusively on the 3.1%-25% of regions rich in signal entropy. To unify spatial and temporal reasoning under irregular token layouts, OneVision-Encoder employs a shared 3D RoPE and is trained with a large-scale cluster discrimination objective over more than one million semantic concepts, jointly capturing object permanence and motion dynamics. Evidence. The results validate our core hypothesis: efficiency and accuracy are not a trade-off; they are positively correlated. When integrated into LLM, it consistently outperforms strong vision backbones such as Qwen3-ViT and SigLIP2 across 16 image, video, and document understanding benchmarks, despite using substantially fewer visual tokens and pretraining data. Notably, on video understanding tasks, OV-Encoder achieves an average improvement of 4.1% over Qwen3-ViT. Codec-aligned, patch-level sparsity is a foundational principle, enabling OV-Encoder as a scalable engine for next-generation visual generalists.
[366] Low-Light Video Enhancement with An Effective Spatial-Temporal Decomposition Paradigm
Xiaogang Xu, Kun Zhou, Tao Hu, Jiafei Wu, Ruixing Wang, Hao Peng, Bei Yu
Main category: cs.CV
TL;DR: VLLVE/VLLVE++: A view-aware low-light video enhancement framework using video decomposition into view-independent (appearance) and view-dependent (shading) components with cross-frame correspondences and scene-level continuity constraints.
Details
Motivation: Low-light video enhancement faces challenges with severe invisibility and noise in dynamic/static scenes. Existing methods need better decomposition strategies to handle complex lighting variations and maintain consistency across frames.Method: Proposes view-aware decomposition with view-independent (appearance) and view-dependent (shading) components. Uses dynamic cross-frame correspondences for view-independent term and scene-level continuity constraints for view-dependent term. Introduces dual-structure enhancement network with cross-frame interaction mechanism. VLLVE++ adds residual term for scene-adaptive degradations and enables bidirectional learning for enhancement and degradation-aware correspondence refinement.
Result: Extensive experiments on LLVE benchmarks show strong performance. VLLVE++ demonstrates capability in handling challenging real-world scenes and high-dynamic videos, effectively increasing reliable correspondences while filtering incorrect ones.
Conclusion: The view-aware decomposition strategy with cross-frame correspondences and continuity constraints effectively enhances low-light videos. VLLVE++’s residual term and bidirectional learning further improve performance for complex real-world scenarios.
Abstract: Low-Light Video Enhancement (LLVE) seeks to restore dynamic or static scenes plagued by severe invisibility and noise. In this paper, we present an innovative video decomposition strategy that incorporates view-independent and view-dependent components to enhance the performance of LLVE. The framework is called View-aware Low-light Video Enhancement (VLLVE). We leverage dynamic cross-frame correspondences for the view-independent term (which primarily captures intrinsic appearance) and impose a scene-level continuity constraint on the view-dependent term (which mainly describes the shading condition) to achieve consistent and satisfactory decomposition results. To further ensure consistent decomposition, we introduce a dual-structure enhancement network featuring a cross-frame interaction mechanism. By supervising different frames simultaneously, this network encourages them to exhibit matching decomposition features. This mechanism can seamlessly integrate with encoder-decoder single-frame networks, incurring minimal additional parameter costs. Building upon VLLVE, we propose a more comprehensive decomposition strategy by introducing an additive residual term, resulting in VLLVE++. This residual term can simulate scene-adaptive degradations, which are difficult to model using a decomposition formulation for common scenes, thereby further enhancing the ability to capture the overall content of videos. In addition, VLLVE++ enables bidirectional learning for both enhancement and degradation-aware correspondence refinement (end-to-end manner), effectively increasing reliable correspondences while filtering out incorrect ones. Notably, VLLVE++ demonstrates strong capability in handling challenging cases, such as real-world scenes and videos with high dynamics. Extensive experiments are conducted on widely recognized LLVE benchmarks.
[367] TimeChat-Captioner: Scripting Multi-Scene Videos with Time-Aware and Structural Audio-Visual Captions
Linli Yao, Yuancheng Wei, Yaojie Zhang, Lei Li, Xinlong Chen, Feifan Song, Ziyue Wang, Kun Ouyang, Yuanxin Liu, Lingpeng Kong, Qi Liu, Pengfei Wan, Kun Gai, Yuanxing Zhang, Xu Sun
Main category: cs.CV
TL;DR: Omni Dense Captioning: A new task for generating continuous, fine-grained audio-visual narratives with timestamps, featuring a benchmark, metric, dataset, and strong baseline model that outperforms Gemini-2.5-Pro.
Details
Motivation: Current video captioning lacks continuous, fine-grained, structured narratives with explicit timestamps. The authors aim to create "script-like" captions that enable vivid scene-by-scene imagination of video content, similar to cinematographic screenplays.Method: 1) Introduces Omni Dense Captioning task with six-dimensional structural schema for script-like captions; 2) Creates OmniDCBench benchmark with human annotations; 3) Proposes SodaM metric for time-aware detailed descriptions; 4) Builds TimeChatCap-42K training dataset; 5) Develops TimeChat-Captioner-7B baseline trained via SFT and GRPO with task-specific rewards.
Result: TimeChat-Captioner-7B achieves state-of-the-art performance, surpassing Gemini-2.5-Pro. Generated dense descriptions significantly boost downstream capabilities in audio-visual reasoning (DailyOmni and WorldSense) and temporal grounding (Charades-STA).
Conclusion: The paper successfully establishes a new task for dense audio-visual narrative generation with structured timestamps, provides comprehensive resources (benchmark, metric, dataset), and demonstrates strong performance with practical benefits for downstream audio-visual reasoning tasks.
Abstract: This paper proposes Omni Dense Captioning, a novel task designed to generate continuous, fine-grained, and structured audio-visual narratives with explicit timestamps. To ensure dense semantic coverage, we introduce a six-dimensional structural schema to create “script-like” captions, enabling readers to vividly imagine the video content scene by scene, akin to a cinematographic screenplay. To facilitate research, we construct OmniDCBench, a high-quality, human-annotated benchmark, and propose SodaM, a unified metric that evaluates time-aware detailed descriptions while mitigating scene boundary ambiguity. Furthermore, we construct a training dataset, TimeChatCap-42K, and present TimeChat-Captioner-7B, a strong baseline trained via SFT and GRPO with task-specific rewards. Extensive experiments demonstrate that TimeChat-Captioner-7B achieves state-of-the-art performance, surpassing Gemini-2.5-Pro, while its generated dense descriptions significantly boost downstream capabilities in audio-visual reasoning (DailyOmni and WorldSense) and temporal grounding (Charades-STA). All datasets, models, and code will be made publicly available at https://github.com/yaolinli/TimeChat-Captioner.
[368] Towards Understanding Multimodal Fine-Tuning: Spatial Features
Lachin Naghashyar, Hunar Batra, Ashkan Khakzar, Philip Torr, Ronald Clark, Christian Schroeder de Witt, Constantin Venhoff
Main category: cs.CV
TL;DR: Mechanistic analysis of how language models learn visual capabilities during multimodal fine-tuning using stage-wise model diffing to identify vision-preferring features and spatial encoding mechanisms.
Details
Motivation: Despite strong performance of Vision-Language Models (VLMs), it remains unclear how language backbone representations adapt during multimodal training and when vision-specific capabilities emerge. The paper aims to provide mechanistic understanding of how language models learn to "see" during fine-tuning.Method: Uses stage-wise model diffing technique to isolate representational changes introduced during multimodal fine-tuning. Identifies vision-preferring features that emerge or reorient, analyzes spatial relation encoding through controlled spatial prompt shifts, and traces causal activation to specific attention heads.
Result: Reveals how language models learn visual capabilities: identifies vision-preferring features, shows selective subset encodes spatial relations, traces activation to specific attention heads. Demonstrates stage-wise model diffing reveals when/where spatially grounded multimodal features arise.
Conclusion: Stage-wise model diffing provides mechanistic understanding of multimodal adaptation, showing how visual grounding reshapes text-only features. Enhances interpretability of multimodal training and provides foundation for understanding how pretrained language models acquire vision-grounded capabilities.
Abstract: Contemporary Vision-Language Models (VLMs) achieve strong performance on a wide range of tasks by pairing a vision encoder with a pre-trained language model, fine-tuned for visual-text inputs. Yet despite these gains, it remains unclear how language backbone representations adapt during multimodal training and when vision-specific capabilities emerge. In this work, we present the first mechanistic analysis of VLM adaptation. Using stage-wise model diffing, a technique that isolates representational changes introduced during multimodal fine-tuning, we reveal how a language model learns to “see”. We first identify vision-preferring features that emerge or reorient during fine-tuning. We then show that a selective subset of these features reliably encodes spatial relations, revealed through controlled shifts to spatial prompts. Finally, we trace the causal activation of these features to a small group of attention heads. Our findings show that stage-wise model diffing reveals when and where spatially grounded multimodal features arise. It also provides a clearer view of modality fusion by showing how visual grounding reshapes features that were previously text-only. This methodology enhances the interpretability of multimodal training and provides a foundation for understanding and refining how pretrained language models acquire vision-grounded capabilities.
[369] Zero-shot System for Automatic Body Region Detection for Volumetric CT and MR Images
Farnaz Khun Jush, Grit Werner, Mark Klemens, Matthias Lenga
Main category: cs.CV
TL;DR: Zero-shot body region detection in CT/MR using foundation models: segmentation-driven rule-based approach outperforms MLLM methods
Details
Motivation: Current body region detection in medical imaging relies on unreliable DICOM metadata and supervised learning, limiting real-world applicability. Need for zero-shot approaches using pre-trained foundation models.Method: Three training-free pipelines: (1) segmentation-driven rule-based system using pre-trained multi-organ segmentation models, (2) MLLM guided by radiologist-defined rules, (3) segmentation-aware MLLM combining visual input with anatomical evidence.
Result: Segmentation-driven rule-based approach achieved best performance: weighted F1-scores of 0.947 (CT) and 0.914 (MR). MLLM performed competitively in visually distinctive regions. Segmentation-aware MLLM showed fundamental limitations.
Conclusion: Zero-shot body region detection is feasible using foundation models. Segmentation-driven rule-based approach is most robust, while MLLMs have potential but current limitations.
Abstract: Reliable identification of anatomical body regions is a prerequisite for many automated medical imaging workflows, yet existing solutions remain heavily dependent on unreliable DICOM metadata. Current solutions mainly use supervised learning, which limits their applicability in many real-world scenarios. In this work, we investigate whether body region detection in volumetric CT and MR images can be achieved in a fully zero-shot manner by using knowledge embedded in large pre-trained foundation models. We propose and systematically evaluate three training-free pipelines: (1) a segmentation-driven rule-based system leveraging pre-trained multi-organ segmentation models, (2) a Multimodal Large Language Model (MLLM) guided by radiologist-defined rules, and (3) a segmentation-aware MLLM that combines visual input with explicit anatomical evidence. All methods are evaluated on 887 heterogeneous CT and MR scans with manually verified anatomical region labels. The segmentation-driven rule-based approach achieves the strongest and most consistent performance, with weighted F1-scores of 0.947 (CT) and 0.914 (MR), demonstrating robustness across modalities and atypical scan coverage. The MLLM performs competitively in visually distinctive regions, while the segmentation-aware MLLM reveals fundamental limitations.
[370] Rotated Lights for Consistent and Efficient 2D Gaussians Inverse Rendering
Geng Lin, Matthias Zwicker
Main category: cs.CV
TL;DR: RotLight: A simple inverse rendering method using object rotation during capture to reduce ambiguity in material and lighting estimation, combined with proxy mesh for improved light tracing and global illumination handling.
Details
Motivation: Current inverse rendering methods inspired by neural radiance fields and Gaussian splatting suffer from ambiguity in material and lighting estimation, leading to inaccurate color and baked shadows in albedo estimation despite regularization techniques.Method: Proposes RotLight capture setup requiring object rotation during capture (as few as two rotations) to reduce ambiguity. Also introduces proxy mesh for accurate incident light tracing, residual constraint, and improved global illumination handling in 2DGS-based inverse rendering.
Result: Demonstrates superior albedo estimation on both synthetic and real-world datasets while maintaining efficient computation compared to prior methods.
Conclusion: RotLight provides an effective yet simple solution to the ambiguity problem in inverse rendering through object rotation during capture and proxy mesh integration, achieving better material decomposition with minimal additional capture requirements.
Abstract: Inverse rendering aims to decompose a scene into its geometry, material properties and light conditions under a certain rendering model. It has wide applications like view synthesis, relighting, and scene editing. In recent years, inverse rendering methods have been inspired by view synthesis approaches like neural radiance fields and Gaussian splatting, which are capable of efficiently decomposing a scene into its geometry and radiance. They then further estimate the material and lighting that lead to the observed scene radiance. However, the latter step is highly ambiguous and prior works suffer from inaccurate color and baked shadows in their albedo estimation albeit their regularization. To this end, we propose RotLight, a simple capturing setup, to address the ambiguity. Compared to a usual capture, RotLight only requires the object to be rotated several times during the process. We show that as few as two rotations is effective in reducing artifacts. To further improve 2DGS-based inverse rendering, we additionally introduce a proxy mesh that not only allows accurate incident light tracing, but also enables a residual constraint and improves global illumination handling. We demonstrate with both synthetic and real world datasets that our method achieves superior albedo estimation while keeping efficient computation.
[371] FusionEdit: Semantic Fusion and Attention Modulation for Training-Free Image Editing
Yongwen Lai, Chaoqun Wang, Shaobo Min
Main category: cs.CV
TL;DR: FusionEdit is a training-free image editing framework that uses semantic discrepancy analysis to identify editing regions, employs distance-aware latent fusion with soft masks to reduce boundary artifacts, and leverages AdaIN-based modulation in DiT attention layers for enhanced editability while preserving source image identity.
Details
Motivation: Current text-guided image editing methods use explicit binary masks which create hard boundaries leading to artifacts and reduced editability. There's a need for more precise and controllable editing that maintains natural transitions and preserves source image identity.Method: 1) Automatically identifies editing vs. preserved regions by measuring semantic discrepancies between source and target prompts. 2) Uses distance-aware latent fusion along region boundaries to create soft masks and applies total variation loss for smooth transitions. 3) Employs AdaIN-based modulation within Diffusion Transformer (DiT) attention layers for statistical attention fusion in editing regions.
Result: Extensive experiments show FusionEdit significantly outperforms state-of-the-art methods in text-guided image editing, achieving more precise and controllable edits with fewer boundary artifacts and better preservation of source image identity.
Conclusion: FusionEdit provides an effective training-free framework for text-guided image editing that addresses boundary artifact issues through soft mask generation and attention modulation, enabling high-quality, controllable edits while maintaining source image consistency.
Abstract: Text-guided image editing aims to modify specific regions according to the target prompt while preserving the identity of the source image. Recent methods exploit explicit binary masks to constrain editing, but hard mask boundaries introduce artifacts and reduce editability. To address these issues, we propose FusionEdit, a training-free image editing framework that achieves precise and controllable edits. First, editing and preserved regions are automatically identified by measuring semantic discrepancies between source and target prompts. To mitigate boundary artifacts, FusionEdit performs distance-aware latent fusion along region boundaries to yield the soft and accurate mask, and employs a total variation loss to enforce smooth transitions, obtaining natural editing results. Second, FusionEdit leverages AdaIN-based modulation within DiT attention layers to perform a statistical attention fusion in the editing region, enhancing editability while preserving global consistency with the source image. Extensive experiments demonstrate that our FusionEdit significantly outperforms state-of-the-art methods. Code is available at \href{https://github.com/Yvan1001/FusionEdit}{https://github.com/Yvan1001/FusionEdit}.
[372] SynSacc: A Blender-to-V2E Pipeline for Synthetic Neuromorphic Eye-Movement Data and Sim-to-Real Spiking Model Training
Khadija Iddrisu, Waseem Shariff, Suzanne Little, Noel OConnor
Main category: cs.CV
TL;DR: Synthetic dataset for eye movement classification using event cameras and Spiking Neural Networks, achieving 0.83 accuracy with computational efficiency gains.
Details
Motivation: Event cameras eliminate motion blur and offer superior temporal resolution for capturing rapid eye movements (saccades and fixations), but real event data is scarce. Synthetic data can help train robust models for eye movement classification.Method: Created synthetic dataset using Blender to simulate saccades and fixations under controlled conditions. Used Spiking Neural Networks (SNNs) trained on synthetic data and fine-tuned on real event data. Compared with artificial neural network (ANN) counterparts.
Result: Models achieved up to 0.83 accuracy in eye movement classification, maintained consistent performance across varying temporal resolutions, and showed substantial computational efficiency gains over ANN counterparts.
Conclusion: Synthetic data augmentation with event cameras and SNNs provides an effective approach for eye movement classification, offering computational efficiency and robustness across temporal resolutions.
Abstract: The study of eye movements, particularly saccades and fixations, are fundamental to understanding the mechanisms of human cognition and perception. Accurate classification of these movements requires sensing technologies capable of capturing rapid dynamics without distortion. Event cameras, also known as Dynamic Vision Sensors (DVS), provide asynchronous recordings of changes in light intensity, thereby eliminating motion blur inherent in conventional frame-based cameras and offering superior temporal resolution and data efficiency. In this study, we introduce a synthetic dataset generated with Blender to simulate saccades and fixations under controlled conditions. Leveraging Spiking Neural Networks (SNNs), we evaluate its robustness by training two architectures and finetuning on real event data. The proposed models achieve up to 0.83 accuracy and maintain consistent performance across varying temporal resolutions, demonstrating stability in eye movement classification. Moreover, the use of SNNs with synthetic event streams yields substantial computational efficiency gains over artificial neural network (ANN) counterparts, underscoring the utility of synthetic data augmentation in advancing event-based vision. All code and datasets associated with this work is available at https: //github.com/Ikhadija-5/SynSacc-Dataset.
[373] Artifact Reduction in Undersampled 3D Cone-Beam CTs using a Hybrid 2D-3D CNN Framework
Johannes Thalhammer, Tina Dorosti, Sebastian Peterhansl, Daniela Pfeiffer, Franz Pfeiffer, Florian Schaff
Main category: cs.CV
TL;DR: Hybrid 2D-3D deep learning framework for artifact reduction in undersampled CT volumes, combining 2D slice processing with 3D volumetric consistency.
Details
Motivation: Undersampled CT volumes reduce acquisition time and radiation exposure but introduce artifacts that degrade image quality and diagnostic utility. There's a need for computationally efficient methods to reduce these artifacts while maintaining volumetric consistency.Method: Two-stage hybrid framework: First, a 2D U-Net processes individual slices of undersampled CT volumes to extract feature maps. These slice-wise feature maps are then stacked and fed into a 3D decoder that uses contextual information across slices to predict artifact-free 3D CT volumes.
Result: The approach shows substantial improvements in inter-slice consistency in coronal and sagittal directions with low computational overhead, balancing computational efficiency with volumetric consistency.
Conclusion: The hybrid framework presents a robust and efficient solution for high-quality 3D CT image post-processing, effectively addressing artifacts in undersampled CT data.
Abstract: Undersampled CT volumes minimize acquisition time and radiation exposure but introduce artifacts degrading image quality and diagnostic utility. Reducing these artifacts is critical for high-quality imaging. We propose a computationally efficient hybrid deep-learning framework that combines the strengths of 2D and 3D models. First, a 2D U-Net operates on individual slices of undersampled CT volumes to extract feature maps. These slice-wise feature maps are then stacked across the volume and used as input to a 3D decoder, which utilizes contextual information across slices to predict an artifact-free 3D CT volume. The proposed two-stage approach balances the computational efficiency of 2D processing with the volumetric consistency provided by 3D modeling. The results show substantial improvements in inter-slice consistency in coronal and sagittal direction with low computational overhead. This hybrid framework presents a robust and efficient solution for high-quality 3D CT image post-processing. The code of this project can be found on github: https://github.com/J-3TO/2D-3DCNN_sparseview/.
[374] Closing the Confusion Loop: CLIP-Guided Alignment for Source-Free Domain Adaptation
Shanshan Wang, Ziying Feng, Xiaozheng Shen, Xun Yang, Pichao Wang, Zhenwei He, Xingyi Zhang
Main category: cs.CV
TL;DR: CLIP-Guided Alignment (CGA) addresses class confusion in Source-Free Domain Adaptation by detecting confusion patterns, using CLIP for context-aware pseudo-labeling, and aligning features to reduce ambiguity.
Details
Motivation: Existing SFDA methods with pseudo-labeling fail in fine-grained scenarios due to asymmetric and dynamic class confusion where visually similar classes are unequally misclassified, leading to noisy pseudo-labels.Method: Three components: MCA detects directional confusion pairs from source model predictions; MCC uses CLIP to create confusion-aware textual prompts for better pseudo-labeling; FAM builds confusion-guided feature banks and aligns them using contrastive learning.
Result: CGA consistently outperforms state-of-the-art SFDA methods across various datasets, with especially notable gains in confusion-prone and fine-grained scenarios.
Conclusion: Explicitly modeling inter-class confusion is crucial for effective source-free adaptation, and CLIP-guided alignment provides a powerful framework for addressing this challenge.
Abstract: Source-Free Domain Adaptation (SFDA) tackles the problem of adapting a pre-trained source model to an unlabeled target domain without accessing any source data, which is quite suitable for the field of data security. Although recent advances have shown that pseudo-labeling strategies can be effective, they often fail in fine-grained scenarios due to subtle inter-class similarities. A critical but underexplored issue is the presence of asymmetric and dynamic class confusion, where visually similar classes are unequally and inconsistently misclassified by the source model. Existing methods typically ignore such confusion patterns, leading to noisy pseudo-labels and poor target discrimination. To address this, we propose CLIP-Guided Alignment(CGA), a novel framework that explicitly models and mitigates class confusion in SFDA. Generally, our method consists of three parts: (1) MCA: detects first directional confusion pairs by analyzing the predictions of the source model in the target domain; (2) MCC: leverages CLIP to construct confusion-aware textual prompts (e.g. a truck that looks like a bus), enabling more context-sensitive pseudo-labeling; and (3) FAM: builds confusion-guided feature banks for both CLIP and the source model and aligns them using contrastive learning to reduce ambiguity in the representation space. Extensive experiments on various datasets demonstrate that CGA consistently outperforms state-of-the-art SFDA methods, with especially notable gains in confusion-prone and fine-grained scenarios. Our results highlight the importance of explicitly modeling inter-class confusion for effective source-free adaptation. Our code can be find at https://github.com/soloiro/CGA
[375] From Correspondence to Actions: Human-Like Multi-Image Spatial Reasoning in Multi-modal Large Language Models
Masanari Oi, Koki Maeda, Ryuto Koike, Daisuke Oba, Nakamasa Inoue, Naoaki Okazaki
Main category: cs.CV
TL;DR: HATCH is a training framework for multimodal LLMs that improves multi-image spatial reasoning through explicit cross-view correspondence and viewpoint change mechanisms, outperforming comparable baselines while maintaining single-image capabilities.
Details
Motivation: Current MLLMs struggle with multi-image spatial reasoning that requires integrating information from multiple viewpoints. While humans use cross-view correspondence and stepwise viewpoint transformation, existing approaches incorporate these mechanisms only partially and implicitly without explicit supervision for both.Method: Proposes HATCH framework with two complementary objectives: (1) Patch-Level Spatial Alignment - encourages patch representations to align across views for spatially corresponding regions, and (2) Action-then-Answer Reasoning - requires generating explicit viewpoint transition actions before predicting final answers.
Result: Experiments on three benchmarks show HATCH consistently outperforms comparable-size baselines by clear margins and achieves competitive results against much larger models, while preserving single-image reasoning capabilities.
Conclusion: Explicitly incorporating both cross-view correspondence and viewpoint change mechanisms through HATCH significantly improves multi-image spatial reasoning in MLLMs, addressing a key limitation in current approaches.
Abstract: While multimodal large language models (MLLMs) have made substantial progress in single-image spatial reasoning, multi-image spatial reasoning, which requires integration of information from multiple viewpoints, remains challenging. Cognitive studies suggest that humans address such tasks through two mechanisms: cross-view correspondence, which identifies regions across different views that correspond to the same physical locations, and stepwise viewpoint transformation, which composes relative viewpoint changes sequentially. However, existing studies incorporate these mechanisms only partially and often implicitly, without explicit supervision for both. We propose Human-Aware Training for Cross-view correspondence and viewpoint cHange (HATCH), a training framework with two complementary objectives: (1) Patch-Level Spatial Alignment, which encourages patch representations to align across views for spatially corresponding regions, and (2) Action-then-Answer Reasoning, which requires the model to generate explicit viewpoint transition actions before predicting the final answer. Experiments on three benchmarks demonstrate that HATCH consistently outperforms baselines of comparable size by a clear margin and achieves competitive results against much larger models, while preserving single-image reasoning capabilities.
[376] Shifting the Breaking Point of Flow Matching for Multi-Instance Editing
Carmine Zaccagnino, Fabio Quattrini, Enis Simsar, Marta Tintoré Gazulla, Rita Cucchiara, Alessio Tonioni, Silvia Cascianelli
Main category: cs.CV
TL;DR: Instance-Disentangled Attention enables multi-instance editing in flow matching models by partitioning attention to bind instance-specific instructions to spatial regions, preventing semantic interference between concurrent edits.
Details
Motivation: Existing flow-based image editors struggle with multi-instance scenarios where multiple parts of a reference input need independent editing without semantic interference, due to globally conditioned velocity fields and joint attention mechanisms that entangle concurrent edits.Method: Introduces Instance-Disentangled Attention that partitions joint attention operations to enforce binding between instance-specific textual instructions and spatial regions during velocity field estimation, enabling disentangled editing.
Result: The approach promotes edit disentanglement and locality while preserving global output coherence, enabling single-pass, instance-level editing on both natural images and text-dense infographics with region-level editing instructions.
Conclusion: Instance-Disentangled Attention effectively addresses the multi-instance editing limitation in flow matching models, enabling independent editing of multiple parts without semantic interference while maintaining overall coherence.
Abstract: Flow matching models have recently emerged as an efficient alternative to diffusion, especially for text-guided image generation and editing, offering faster inference through continuous-time dynamics. However, existing flow-based editors predominantly support global or single-instruction edits and struggle with multi-instance scenarios, where multiple parts of a reference input must be edited independently without semantic interference. We identify this limitation as a consequence of globally conditioned velocity fields and joint attention mechanisms, which entangle concurrent edits. To address this issue, we introduce Instance-Disentangled Attention, a mechanism that partitions joint attention operations, enforcing binding between instance-specific textual instructions and spatial regions during velocity field estimation. We evaluate our approach on both natural image editing and a newly introduced benchmark of text-dense infographics with region-level editing instructions. Experimental results demonstrate that our approach promotes edit disentanglement and locality while preserving global output coherence, enabling single-pass, instance-level editing.
[377] MVAnimate: Enhancing Character Animation with Multi-View Optimization
Tianyu Sun, Zhoujie Fu, Bang Zhang, Guosheng Lin
Main category: cs.CV
TL;DR: MVAnimate: A framework for generating high-quality character animation by synthesizing 2D and 3D information using multi-view prior information to enhance temporal consistency and spatial coherence.
Details
Motivation: Current character animation methods face limitations including low-quality output and training data deficiencies when modeling human pose with 2D or 3D structures, preventing generation of high-quality animation videos.Method: MVAnimate synthesizes both 2D and 3D information of dynamic figures based on multi-view prior information. It leverages multi-view data to produce temporally consistent and spatially coherent animations, and optimizes multi-view videos of target characters from different views.
Result: Experimental results on diverse datasets demonstrate robustness in handling various motion patterns and appearances, showing improvements over existing animation methods in generated video quality.
Conclusion: MVAnimate provides a novel framework that addresses quality limitations in character animation generation by effectively utilizing multi-view prior information for enhanced 2D and 3D animation synthesis.
Abstract: The demand for realistic and versatile character animation has surged, driven by its wide-ranging applications in various domains. However, the animation generation algorithms modeling human pose with 2D or 3D structures all face various problems, including low-quality output content and training data deficiency, preventing the related algorithms from generating high-quality animation videos. Therefore, we introduce MVAnimate, a novel framework that synthesizes both 2D and 3D information of dynamic figures based on multi-view prior information, to enhance the generated video quality. Our approach leverages multi-view prior information to produce temporally consistent and spatially coherent animation outputs, demonstrating improvements over existing animation methods. Our MVAnimate also optimizes the multi-view videos of the target character, enhancing the video quality from different views. Experimental results on diverse datasets highlight the robustness of our method in handling various motion patterns and appearances.
[378] VedicTHG: Symbolic Vedic Computation for Low-Resource Talking-Head Generation in Educational Avatars
Vineet Kumar Rakesh, Ahana Bhattacharjee, Soumya Mazumdar, Tapas Samanta, Hemendra Kumar Pandey, Amitabha Das, Sarbajit Pal
Main category: cs.CV
TL;DR: A CPU-oriented talking-head generation framework using symbolic Vedic computation for educational avatars, achieving real-time synthesis on low-end hardware with phoneme-to-viseme mapping and lightweight rendering.
Details
Motivation: Current talking-head generation methods rely on GPU-centric neural rendering, large training sets, or high-capacity diffusion models, which are unsuitable for offline or resource-constrained learning environments. There's a need for deterministic, CPU-oriented solutions for educational avatars.Method: Symbolic Vedic Computation framework: converts speech to time-aligned phonemes, maps phonemes to compact viseme inventory, produces smooth viseme trajectories using symbolic coarticulation inspired by Vedic sutra Urdhva Tiryakbhyam, and uses lightweight 2D renderer with ROI warping and mouth compositing for real-time CPU synthesis.
Result: Achieves acceptable lip-sync quality while substantially reducing computational load and latency. Demonstrates synchronization accuracy, temporal stability, and identity consistency under CPU-only execution, outperforming representative CPU-feasible baselines.
Conclusion: The framework enables practical educational avatars on low-end hardware by providing a deterministic, CPU-oriented talking-head generation solution that balances quality with computational efficiency.
Abstract: Talking-head avatars are increasingly adopted in educational technology to deliver content with social presence and improved engagement. However, many recent talking-head generation (THG) methods rely on GPU-centric neural rendering, large training sets, or high-capacity diffusion models, which limits deployment in offline or resource-constrained learning environments. A deterministic and CPU-oriented THG framework is described, termed Symbolic Vedic Computation, that converts speech to a time-aligned phoneme stream, maps phonemes to a compact viseme inventory, and produces smooth viseme trajectories through symbolic coarticulation inspired by Vedic sutra Urdhva Tiryakbhyam. A lightweight 2D renderer performs region-of-interest (ROI) warping and mouth compositing with stabilization to support real-time synthesis on commodity CPUs. Experiments report synchronization accuracy, temporal stability, and identity consistency under CPU-only execution, alongside benchmarking against representative CPU-feasible baselines. Results indicate that acceptable lip-sync quality can be achieved while substantially reducing computational load and latency, supporting practical educational avatars on low-end hardware. GitHub: https://vineetkumarrakesh.github.io/vedicthg
[379] Multimodal Learning for Arcing Detection in Pantograph-Catenary Systems
Hao Dong, Eleni Chatzi, Olga Fink
Main category: cs.CV
TL;DR: A multimodal framework combining high-resolution images and force measurements for detecting electrical arcing at pantograph-catenary interfaces in rail systems, using novel datasets and an extended DeepSAD algorithm with modality-specific pseudo-anomaly generation.
Details
Motivation: Electrical arcing at pantograph-catenary interfaces in rail systems causes accelerated wear, degraded performance, and service disruptions. Detection is challenging due to transient nature, noisy environments, data scarcity, and difficulty distinguishing arcs from similar transient phenomena.Method: Proposes MultiDeepSAD, an extension of DeepSAD algorithm for multiple modalities with new loss formulation. Creates two multimodal datasets (real SBB data and synthetic/public video data) with synchronized visual and force measurements. Introduces modality-specific pseudo-anomaly generation techniques for images (synthetic arc-like artifacts) and force data (simulated irregularities) to augment training.
Result: Framework significantly outperforms baseline approaches, showing enhanced sensitivity to real arcing events even under domain shifts and limited availability of real arcing observations. Extensive experiments and ablation studies validate the approach.
Conclusion: The multimodal framework combining visual and force data with tailored augmentation techniques provides more accurate and robust arcing detection for rail systems, addressing challenges of data scarcity and noisy environments.
Abstract: The pantograph-catenary interface is essential for ensuring uninterrupted and reliable power delivery in electrified rail systems. However, electrical arcing at this interface poses serious risks, including accelerated wear of contact components, degraded system performance, and potential service disruptions. Detecting arcing events at the pantograph-catenary interface is challenging due to their transient nature, noisy operating environment, data scarcity, and the difficulty of distinguishing arcs from other similar transient phenomena. To address these challenges, we propose a novel multimodal framework that combines high-resolution image data with force measurements to more accurately and robustly detect arcing events. First, we construct two arcing detection datasets comprising synchronized visual and force measurements. One dataset is built from data provided by the Swiss Federal Railways (SBB), and the other is derived from publicly available videos of arcing events in different railway systems and synthetic force data that mimic the characteristics observed in the real dataset. Leveraging these datasets, we propose MultiDeepSAD, an extension of the DeepSAD algorithm for multiple modalities with a new loss formulation. Additionally, we introduce tailored pseudo-anomaly generation techniques specific to each data type, such as synthetic arc-like artifacts in images and simulated force irregularities, to augment training data and improve the discriminative ability of the model. Through extensive experiments and ablation studies, we demonstrate that our framework significantly outperforms baseline approaches, exhibiting enhanced sensitivity to real arcing events even under domain shifts and limited availability of real arcing observations.
[380] Addressing data annotation scarcity in Brain Tumor Segmentation on 3D MRI scan Using a Semi-Supervised Teacher-Student Framework
Jiaming Liu, Cheng Ding, Daoqiang Zhang
Main category: cs.CV
TL;DR: Semi-supervised teacher-student framework for brain tumor segmentation from MRI using uncertainty-aware pseudo-labeling and confidence-based curriculum learning to address limited annotations and data heterogeneity.
Details
Motivation: Brain tumor segmentation from MRI faces challenges with expensive annotations and data heterogeneity across different scanners and sites, requiring methods that can work effectively with limited labeled data.Method: Proposes a teacher-student framework where the teacher generates probabilistic masks with per-pixel uncertainty. Unlabeled scans are ranked by image-level confidence and introduced progressively. The student uses a dual-loss objective to learn from high-confidence regions and unlearn low-confidence ones, with agreement-based refinement improving pseudo-label quality.
Result: On BraTS 2021, validation DSC increased from 0.393 (10% data) to 0.872 (100%), with largest gains in early stages. Teacher reached DSC of 0.922, and student surpassed teacher on tumor subregions (NCR/NET 0.797, Edema 0.980) and recovered Enhancing class (DSC 0.620) where teacher failed.
Conclusion: Confidence-driven curricula and selective unlearning provide robust segmentation under limited supervision and noisy pseudo-labels, demonstrating data efficiency and effectiveness in handling data heterogeneity.
Abstract: Accurate brain tumor segmentation from MRI is limited by expensive annotations and data heterogeneity across scanners and sites. We propose a semi-supervised teacher-student framework that combines an uncertainty-aware pseudo-labeling teacher with a progressive, confidence-based curriculum for the student. The teacher produces probabilistic masks and per-pixel uncertainty; unlabeled scans are ranked by image-level confidence and introduced in stages, while a dual-loss objective trains the student to learn from high-confidence regions and unlearn low-confidence ones. Agreement-based refinement further improves pseudo-label quality. On BraTS 2021, validation DSC increased from 0.393 (10% data) to 0.872 (100%), with the largest gains in early stages, demonstrating data efficiency. The teacher reached a validation DSC of 0.922, and the student surpassed the teacher on tumor subregions (e.g., NCR/NET 0.797 and Edema 0.980); notably, the student recovered the Enhancing class (DSC 0.620) where the teacher failed. These results show that confidence-driven curricula and selective unlearning provide robust segmentation under limited supervision and noisy pseudo-labels.
[381] Omni-Video 2: Scaling MLLM-Conditioned Diffusion for Unified Video Generation and Editing
Hao Yang, Zhiyu Tan, Jia Gong, Luozheng Qin, Hesen Chen, Xiaomeng Yang, Yuqing Sun, Yuetan Lin, Mengping Yang, Hao Li
Main category: cs.CV
TL;DR: Omni-Video 2 connects pretrained MLLMs with video diffusion models for unified video generation and editing, using MLLMs to interpret user instructions and guide generation through lightweight adapters.
Details
Motivation: To create a scalable and efficient system that leverages the understanding capabilities of multimodal LLMs to improve video generation and editing, particularly for complex compositional tasks.Method: Uses MLLMs to produce explicit target captions from user instructions, then employs lightweight adapters to inject multimodal conditional tokens into pretrained text-to-video diffusion models, enabling parameter-efficient reuse of generative priors.
Result: Achieves superior performance on complex compositional video editing (FiVE benchmark) and competitive/superior quality in text-to-video generation (VBench benchmark). Scaled to 14B parameters with high-quality training data.
Conclusion: The approach successfully bridges MLLM understanding with video diffusion generation, enabling effective handling of complex video editing tasks while maintaining strong video generation capabilities.
Abstract: We present Omni-Video 2, a scalable and computationally efficient model that connects pretrained multimodal large-language models (MLLMs) with video diffusion models for unified video generation and editing. Our key idea is to exploit the understanding and reasoning capabilities of MLLMs to produce explicit target captions to interpret user instructions. In this way, the rich contextual representations from the understanding model are directly used to guide the generative process, thereby improving performance on complex and compositional editing. Moreover, a lightweight adapter is developed to inject multimodal conditional tokens into pretrained text-to-video diffusion models, allowing maximum reuse of their powerful generative priors in a parameter-efficient manner. Benefiting from these designs, we scale up Omni-Video 2 to a 14B video diffusion model on meticulously curated training data with quality, supporting high quality text-to-video generation and various video editing tasks such as object removal, addition, background change, complex motion editing, \emph{etc.} We evaluate the performance of Omni-Video 2 on the FiVE benchmark for fine-grained video editing and the VBench benchmark for text-to-video generation. The results demonstrate its superior ability to follow complex compositional instructions in video editing, while also achieving competitive or superior quality in video generation tasks.
[382] Any-to-All MRI Synthesis: A Unified Foundation Model for Nasopharyngeal Carcinoma and Its Downstream Applications
Yao Pu, Yiming Shi, Zhenxi Zhang, Peixin Yu, Yitao Zhuang, Xiang Wang, Hongzhao Chen, Jing Cai, Ge Ren
Main category: cs.CV
TL;DR: A unified foundation model for any-to-all MRI synthesis using contrastive visual representation learning and vision-language alignment, specifically designed for nasopharyngeal carcinoma radiotherapy planning.
Details
Motivation: MRI is crucial for nasopharyngeal carcinoma radiotherapy planning, but practical constraints often lead to incomplete modalities in clinical practice, compromising accuracy. Traditional MRI synthesis methods are modality-specific, lack anatomical adaptability, and have poor clinical interpretability.Method: Developed a unified foundation model integrating contrastive visual representation learning and vision-language alignment. Uses a contrastive encoder for modality-invariant representations and a CLIP-based text-informed decoder for semantically consistent synthesis, enabling any-to-all MRI synthesis via one unified model.
Result: Trained on 40,825 images from 13 institutions, achieved consistently high performance (average SSIM 0.90, PSNR 27) across 26 internal/external validation sites (15,748 images). Shows superior synthesis fidelity and robustness to noise and domain shifts. Unified representation also enhances downstream radiotherapy-relevant tasks like segmentation.
Conclusion: The work advances digital medicine solutions for NPC care by leveraging foundation models to bridge technical synthesis and clinical utility, providing a unified approach for MRI synthesis in radiotherapy planning.
Abstract: Magnetic resonance imaging (MRI) is essential for nasopharyngeal carcinoma (NPC) radiotherapy (RT), but practical constraints, such as patient discomfort, long scan times, and high costs often lead to incomplete modalities in clinical practice, compromising RT planning accuracy. Traditional MRI synthesis methods are modality-specific, limited in anatomical adaptability, and lack clinical interpretability-failing to meet NPC’s RT needs. Here, we developed a unified foundation model integrating contrastive visual representation learning and vision-language alignment (VLA) to enable any-to-all MRI synthesis. The model uses a contrastive encoder for modality-invariant representations and a CLIP-based text-informed decoder for semantically consistent synthesis, supporting any-to-all MRI synthesis via one unified foundation model. Trained on 40,825 images from 13 institutions, it achieves consistently high performance (average SSIM 0.90, PSNR 27) across 26 internal/external validation sites (15,748 images), with superior synthesis fidelity and robustness to noise and domain shifts. Meanwhile, its unified representation enhances downstream RT-relevant tasks (e.g., segmentation). This work advances digital medicine solutions for NPC care by leveraging foundation models to bridge technical synthesis and clinical utility.
[383] VideoVeritas: AI-Generated Video Detection via Perception Pretext Reinforcement Learning
Hao Tan, Jun Lan, Senyuan Shi, Zichang Tan, Zijian Yu, Huijia Zhu, Weiqiang Wang, Jun Wan, Zhen Lei
Main category: cs.CV
TL;DR: VideoVeritas: A framework for video deepfake detection using fine-grained perception and fact-based reasoning via joint preference alignment and perception pretext reinforcement learning, evaluated on the MintVid dataset.
Details
Motivation: The growing capability of video generation poses escalating security risks, making reliable detection increasingly essential. Current multimodal large language models (MLLMs) exhibit strong reasoning capacity but limited granular perception ability for effective video deepfake detection.Method: Introduces VideoVeritas framework with Joint Preference Alignment and Perception Pretext Reinforcement Learning (PPRL). Instead of directly optimizing for detection, uses general spatiotemporal grounding and self-supervised object counting in RL stage to enhance detection performance with simple perception pretext tasks. Also introduces MintVid dataset with 3K videos from 9 state-of-the-art generators and real-world factual error subset.
Result: Experimental results show existing methods bias toward either superficial reasoning or mechanical analysis, while VideoVeritas achieves more balanced performance across diverse benchmarks.
Conclusion: VideoVeritas effectively integrates fine-grained perception and fact-based reasoning for video deepfake detection, addressing limitations of current MLLMs through novel reinforcement learning approach and comprehensive evaluation dataset.
Abstract: The growing capability of video generation poses escalating security risks, making reliable detection increasingly essential. In this paper, we introduce VideoVeritas, a framework that integrates fine-grained perception and fact-based reasoning. We observe that while current multi-modal large language models (MLLMs) exhibit strong reasoning capacity, their granular perception ability remains limited. To mitigate this, we introduce Joint Preference Alignment and Perception Pretext Reinforcement Learning (PPRL). Specifically, rather than directly optimizing for detection task, we adopt general spatiotemporal grounding and self-supervised object counting in the RL stage, enhancing detection performance with simple perception pretext tasks. To facilitate robust evaluation, we further introduce MintVid, a light yet high-quality dataset containing 3K videos from 9 state-of-the-art generators, along with a real-world collected subset that has factual errors in content. Experimental results demonstrate that existing methods tend to bias towards either superficial reasoning or mechanical analysis, while VideoVeritas achieves more balanced performance across diverse benchmarks.
[384] FlattenGPT: Depth Compression for Transformer with Layer Flattening
Ruihan Xu, Qingpei Guo, Yao Zhu, Xiangyang Ji, Ming Yang, Shiliang Zhang
Main category: cs.CV
TL;DR: FlattenGPT is a novel depth compression method for transformers that flattens adjacent blocks to reduce depth while preserving knowledge, outperforming existing pruning methods in efficiency-performance trade-offs.
Details
Motivation: Current transformer block pruning methods risk discarding meaningful learned cues, while channel pruning cannot reduce model depth and faces inconsistent pruning ratios across layers. There's a need for better depth compression that preserves knowledge while reducing redundancy.Method: FlattenGPT detects and reduces depth-wise redundancies by flattening two adjacent transformer blocks into one, compressing network depth while enabling more effective parameter redundancy detection and removal. It maintains the original transformer architecture.
Result: Outperforms existing pruning methods in zero-shot accuracies and WikiText-2 perplexity across various model types and sizes. On LLaMA-2/3 and Qwen-1.5 models, retains 90-96% of zero-shot performance with 20% compression ratio. Also better at accelerating LLM inference.
Conclusion: FlattenGPT provides an effective approach for transformer compression that balances efficiency and performance, making it promising for enhancing transformer efficiency while preserving learned knowledge.
Abstract: Recent works have indicated redundancy across transformer blocks, prompting the research of depth compression to prune less crucial blocks. However, current ways of entire-block pruning suffer from risks of discarding meaningful cues learned in those blocks, leading to substantial performance degradation. As another line of model compression, channel pruning can better preserve performance, while it cannot reduce model depth and is challenged by inconsistent pruning ratios for individual layers. To pursue better model compression and acceleration, this paper proposes \textbf{FlattenGPT}, a novel way to detect and reduce depth-wise redundancies. By flatting two adjacent blocks into one, it compresses the network depth, meanwhile enables more effective parameter redundancy detection and removal. FlattenGPT allows to preserve the knowledge learned in all blocks, and remains consistent with the original transformer architecture. Extensive experiments demonstrate that FlattenGPT enhances model efficiency with a decent trade-off to performance. It outperforms existing pruning methods in both zero-shot accuracies and WikiText-2 perplexity across various model types and parameter sizes. On LLaMA-2/3 and Qwen-1.5 models, FlattenGPT retains 90-96% of zero-shot performance with a compression ratio of 20%. It also outperforms other pruning methods in accelerating LLM inference, making it promising for enhancing the efficiency of transformers.
[385] TiFRe: Text-guided Video Frame Reduction for Efficient Video Multi-modal Large Language Models
Xiangtian Zheng, Zishuo Wang, Yuxin Peng
Main category: cs.CV
TL;DR: TiFRe is a framework that reduces computational costs in Video MLLMs by intelligently selecting key frames based on text guidance and merging non-key frame information, improving efficiency while maintaining performance.
Details
Motivation: Video MLLMs face high computational costs due to processing numerous video frames, leading to significant attention computation overhead. Simply reducing frames at fixed rates causes information loss and performance degradation.Method: Proposes Text-guided Video Frame Reduction (TiFRe) with two components: 1) Text-guided Frame Sampling (TFS) uses LLM-generated CLIP-style prompts to select semantically relevant frames, and 2) Frame Matching and Merging (FMM) integrates non-key frame information into selected key frames to preserve video semantics.
Result: Experiments show TiFRe effectively reduces computational costs while improving performance on video-language tasks compared to fixed frame rate approaches.
Conclusion: TiFRe provides an efficient solution for Video MLLMs by intelligently reducing input frames while preserving essential video information, addressing computational bottlenecks in video processing.
Abstract: With the rapid development of Large Language Models (LLMs), Video Multi-Modal Large Language Models (Video MLLMs) have achieved remarkable performance in video-language tasks such as video understanding and question answering. However, Video MLLMs face high computational costs, particularly in processing numerous video frames as input, which leads to significant attention computation overhead. A straightforward approach to reduce computational costs is to decrease the number of input video frames. However, simply selecting key frames at a fixed frame rate (FPS) often overlooks valuable information in non-key frames, resulting in notable performance degradation. To address this, we propose Text-guided Video Frame Reduction (TiFRe), a framework that reduces input frames while preserving essential video information. TiFRe uses a Text-guided Frame Sampling (TFS) strategy to select key frames based on user input, which is processed by an LLM to generate a CLIP-style prompt. Pre-trained CLIP encoders calculate the semantic similarity between the prompt and each frame, selecting the most relevant frames as key frames. To preserve video semantics, TiFRe employs a Frame Matching and Merging (FMM) mechanism, which integrates non-key frame information into the selected key frames, minimizing information loss. Experiments show that TiFRe effectively reduces computational costs while improving performance on video-language tasks.
[386] Analysis of Converged 3D Gaussian Splatting Solutions: Density Effects and Prediction Limit
Zhendong Wang, Cihan Ruan, Jingchuan Xiao, Chuqing Shi, Wei Jiang, Wei Wang, Wenjie Liu, Nam Ling
Main category: cs.CV
TL;DR: Analysis of 3D Gaussian Splatting reveals stable statistical patterns in rendering-optimal references, with learnability probes showing density-stratification: dense regions allow geometry-correlated parameter prediction while sparse regions require multi-view constraints.
Details
Motivation: To understand what structural patterns emerge in 3D Gaussian Splatting solutions from standard multi-view optimization, and to determine what factors govern these parameters for better training and architectural design.Method: Analyze statistical properties of Rendering-Optimal References (RORs) from 3DGS optimization, then use learnability probes with predictors trained to reconstruct RORs from point clouds without rendering supervision, followed by variance decomposition analysis.
Result: Reveals stable patterns: mixture-structured scales and bimodal radiance across scenes. Shows fundamental density-stratification: dense regions have geometry-correlated parameters predictable from point clouds, while sparse regions show systematic failure due to visibility heterogeneity creating covariance-dominated coupling.
Conclusion: RORs have dual character: geometric primitives where point clouds suffice, and view synthesis primitives where multi-view constraints are essential. Provides density-aware strategies for training robustness and architectural implications for balancing feed-forward prediction with rendering-based refinement.
Abstract: We investigate what structure emerges in 3D Gaussian Splatting (3DGS) solutions from standard multi-view optimization. We term these Rendering-Optimal References (RORs) and analyze their statistical properties, revealing stable patterns: mixture-structured scales and bimodal radiance across diverse scenes. To understand what determines these parameters, we apply learnability probes by training predictors to reconstruct RORs from point clouds without rendering supervision. Our analysis uncovers fundamental density-stratification. Dense regions exhibit geometry-correlated parameters amenable to render-free prediction, while sparse regions show systematic failure across architectures. We formalize this through variance decomposition, demonstrating that visibility heterogeneity creates covariance-dominated coupling between geometric and appearance parameters in sparse regions. This reveals the dual character of RORs: geometric primitives where point clouds suffice, and view synthesis primitives where multi-view constraints are essential. We provide density-aware strategies that improve training robustness and discuss architectural implications for systems that adaptively balance feed-forward prediction and rendering-based refinement.
[387] Grow with the Flow: 4D Reconstruction of Growing Plants with Gaussian Flow Fields
Weihan Luo, Lily Goli, Sherwin Bahmani, Felix Taubner, Andrea Tagliasacchi, David B. Lindell
Main category: cs.CV
TL;DR: A 3D Gaussian flow field representation for modeling plant growth as time-varying derivatives over Gaussian parameters, enabling nonlinear continuous-time growth dynamics with superior image quality and geometric accuracy.
Details
Motivation: Modeling time-varying 3D appearance of growing plants is challenging because existing motion modeling techniques (deformation fields, 4D Gaussian splatting) cannot handle the generation of new geometry over time or track the same set of Gaussians through growth processes.Method: Introduces a 3D Gaussian flow field representation that models plant growth as time-varying derivatives over Gaussian parameters (position, scale, orientation, color, opacity). Initializes Gaussians by reconstructing the mature plant and learning reverse growth to simulate developmental history in reverse.
Result: Achieves superior image quality and geometric accuracy compared to prior methods on multi-view timelapse datasets of plant growth, providing a new approach for appearance modeling of growing 3D structures.
Conclusion: The 3D Gaussian flow field representation effectively models plant growth dynamics, handling the unique challenges of new geometry generation over time while maintaining tracking of Gaussian primitives through continuous-time nonlinear growth.
Abstract: Modeling the time-varying 3D appearance of plants during their growth poses unique challenges: unlike many dynamic scenes, plants generate new geometry over time as they expand, branch, and differentiate. Recent motion modeling techniques are ill-suited to this problem setting. For example, deformation fields cannot introduce new geometry, and 4D Gaussian splatting constrains motion to a linear trajectory in space and time and cannot track the same set of Gaussians over time. Here, we introduce a 3D Gaussian flow field representation that models plant growth as a time-varying derivative over Gaussian parameters – position, scale, orientation, color, and opacity – enabling nonlinear and continuous-time growth dynamics. To initialize a sufficient set of Gaussian primitives, we reconstruct the mature plant and learn a process of reverse growth, effectively simulating the plant’s developmental history in reverse. Our approach achieves superior image quality and geometric accuracy compared to prior methods on multi-view timelapse datasets of plant growth, providing a new approach for appearance modeling of growing 3D structures.
[388] MotionCrafter: Dense Geometry and Motion Reconstruction with a 4D VAE
Ruijie Zhu, Jiahao Lu, Wenbo Hu, Xiaoguang Han, Jianfei Cai, Ying Shan, Chuanxia Zheng
Main category: cs.CV
TL;DR: MotionCrafter is a video diffusion framework that jointly reconstructs 4D geometry and estimates dense motion from monocular videos using a novel joint representation and 4D VAE.
Details
Motivation: Prior methods force alignment between 3D geometry/motion representations and RGB VAE latents despite their fundamentally different distributions, leading to suboptimal performance. The authors aim to develop a better approach for joint 4D reconstruction and motion estimation.Method: Introduces a novel joint representation of dense 3D point maps and 3D scene flows in a shared coordinate system, and a novel 4D VAE to learn this representation. Uses a new data normalization and VAE training strategy that better transfers diffusion priors instead of forcing alignment with RGB VAE latents.
Result: Achieves state-of-the-art performance with 38.64% improvement in geometry reconstruction and 25.0% improvement in motion reconstruction across multiple datasets, all without post-optimization.
Conclusion: MotionCrafter demonstrates that forcing alignment between 3D geometry/motion representations and RGB VAE latents is unnecessary and suboptimal, and that the proposed joint representation with proper normalization and training strategy significantly improves 4D reconstruction quality.
Abstract: We introduce MotionCrafter, a video diffusion-based framework that jointly reconstructs 4D geometry and estimates dense motion from a monocular video. The core of our method is a novel joint representation of dense 3D point maps and 3D scene flows in a shared coordinate system, and a novel 4D VAE to effectively learn this representation. Unlike prior work that forces the 3D value and latents to align strictly with RGB VAE latents-despite their fundamentally different distributions-we show that such alignment is unnecessary and leads to suboptimal performance. Instead, we introduce a new data normalization and VAE training strategy that better transfers diffusion priors and greatly improves reconstruction quality. Extensive experiments across multiple datasets demonstrate that MotionCrafter achieves state-of-the-art performance in both geometry reconstruction and dense scene flow estimation, delivering 38.64% and 25.0% improvements in geometry and motion reconstruction, respectively, all without any post-optimization. Project page: https://ruijiezhu94.github.io/MotionCrafter_Page
[389] Modeling 3D Pedestrian-Vehicle Interactions for Vehicle-Conditioned Pose Forecasting
Guangxun Zhu, Xuan Liu, Nicolas Pugeault, Chongfeng Wei, Edmond S. L. Ho
Main category: cs.CV
TL;DR: 3D vehicle-conditioned pedestrian pose forecasting framework that incorporates surrounding vehicle information for improved motion prediction in autonomous driving scenarios.
Details
Motivation: Accurate pedestrian motion prediction is crucial for safe autonomous driving in complex urban environments, requiring explicit modeling of pedestrian-vehicle interactions.Method: Enhanced Waymo-3DSkelMo dataset with 3D vehicle bounding boxes, introduced sampling scheme for varying interaction complexities, adapted TBIFormer architecture with vehicle encoder and pedestrian-vehicle interaction cross-attention module.
Result: Substantial improvements in forecasting accuracy, validated different approaches for modeling pedestrian-vehicle interactions, demonstrated importance of vehicle-aware 3D pose prediction.
Conclusion: Vehicle-conditioned 3D pedestrian pose forecasting significantly improves prediction accuracy for autonomous driving by explicitly modeling pedestrian-vehicle interactions.
Abstract: Accurately predicting pedestrian motion is crucial for safe and reliable autonomous driving in complex urban environments. In this work, we present a 3D vehicle-conditioned pedestrian pose forecasting framework that explicitly incorporates surrounding vehicle information. To support this, we enhance the Waymo-3DSkelMo dataset with aligned 3D vehicle bounding boxes, enabling realistic modeling of multi-agent pedestrian-vehicle interactions. We introduce a sampling scheme to categorize scenes by pedestrian and vehicle count, facilitating training across varying interaction complexities. Our proposed network adapts the TBIFormer architecture with a dedicated vehicle encoder and pedestrian-vehicle interaction cross-attention module to fuse pedestrian and vehicle features, allowing predictions to be conditioned on both historical pedestrian motion and surrounding vehicles. Extensive experiments demonstrate substantial improvements in forecasting accuracy and validate different approaches for modeling pedestrian-vehicle interactions, highlighting the importance of vehicle-aware 3D pose prediction for autonomous driving. Code is available at: https://github.com/GuangxunZhu/VehCondPose3D
[390] WorldArena: A Unified Benchmark for Evaluating Perception and Functional Utility of Embodied World Models
Yu Shang, Zhuohang Li, Yiding Ma, Weikang Su, Xin Jin, Ziyou Wang, Xin Zhang, Yinzhou Tang, Chen Gao, Wei Wu, Xihui Liu, Dhruv Shah, Zhaoxiang Zhang, Zhibo Chen, Jun Zhu, Yonghong Tian, Tat-Seng Chua, Wenwu Zhu, Yong Li
Main category: cs.CV
TL;DR: WorldArena is a unified benchmark for evaluating embodied world models across both perceptual quality (video generation) and functional utility (downstream decision-making tasks), revealing a perception-functionality gap.
Details
Motivation: Current evaluation of embodied world models focuses too narrowly on perceptual fidelity (video generation quality) while overlooking their functional utility in downstream decision-making tasks, creating fragmented evaluation practices.Method: Introduces WorldArena benchmark with three evaluation dimensions: 1) video perception quality (16 metrics across 6 sub-dimensions), 2) embodied task functionality (evaluating models as data engines, policy evaluators, and action planners with human evaluation), and 3) EWMScore - a holistic metric integrating multi-dimensional performance into a single interpretable index.
Result: Extensive experiments on 14 representative models reveal a significant perception-functionality gap, showing that high visual quality does not necessarily translate into strong embodied task capability.
Conclusion: WorldArena provides a comprehensive framework for tracking progress toward truly functional world models in embodied AI, addressing the current fragmented evaluation landscape and emphasizing the importance of functional utility beyond mere perceptual quality.
Abstract: While world models have emerged as a cornerstone of embodied intelligence by enabling agents to reason about environmental dynamics through action-conditioned prediction, their evaluation remains fragmented. Current evaluation of embodied world models has largely focused on perceptual fidelity (e.g., video generation quality), overlooking the functional utility of these models in downstream decision-making tasks. In this work, we introduce WorldArena, a unified benchmark designed to systematically evaluate embodied world models across both perceptual and functional dimensions. WorldArena assesses models through three dimensions: video perception quality, measured with 16 metrics across six sub-dimensions; embodied task functionality, which evaluates world models as data engines, policy evaluators, and action planners integrating with subjective human evaluation. Furthermore, we propose EWMScore, a holistic metric integrating multi-dimensional performance into a single interpretable index. Through extensive experiments on 14 representative models, we reveal a significant perception-functionality gap, showing that high visual quality does not necessarily translate into strong embodied task capability. WorldArena benchmark with the public leaderboard is released at https://worldarena.ai, providing a framework for tracking progress toward truly functional world models in embodied AI.
[391] Generalizing Sports Feedback Generation by Watching Competitions and Reading Books: A Rock Climbing Case Study
Arushi Rai, Adriana Kovashka
Main category: cs.CV
TL;DR: Proposes using auxiliary web data (competition videos, coaching manuals) to improve sports feedback generation in video-LLMs, with new evaluation metrics for specificity and actionability.
Details
Motivation: Video-LLMs struggle with sports feedback generation, requiring expensive fine-tuning data and showing poor generalization to unseen sports. Existing text generation metrics fail to capture sports feedback quality aspects.Method: Uses rock climbing as case study, leveraging auxiliary freely-available web data (competition videos, coaching manuals) from target domain plus existing sports feedback from source domain. Proposes two new evaluation metrics: specificity and actionability.
Result: Enables more meaningful and practical generation of sports feedback under limited annotations by improving performance on target domain and providing better evaluation.
Conclusion: The approach addresses limitations in sports feedback generation for video-LLMs by using auxiliary domain data and introducing domain-specific evaluation metrics.
Abstract: While there is rapid progress in video-LLMs with advanced reasoning capabilities, prior work shows that these models struggle on the challenging task of sports feedback generation and require expensive and difficult-to-collect finetuning feedback data for each sport. This limitation is evident from the poor generalization to sports unseen during finetuning. Furthermore, traditional text generation evaluation metrics (e.g., BLEU-4, METEOR, ROUGE-L, BERTScore), originally developed for machine translation and summarization, fail to capture the unique aspects of sports feedback quality. To address the first problem, using rock climbing as our case study, we propose using auxiliary freely-available web data from the target domain, such as competition videos and coaching manuals, in addition to existing sports feedback from a disjoint, source domain to improve sports feedback generation performance on the target domain. To improve evaluation, we propose two evaluation metrics: (1) specificity and (2) actionability. Together, our approach enables more meaningful and practical generation of sports feedback under limited annotations.
[392] ArcFlow: Unleashing 2-Step Text-to-Image Generation via High-Precision Non-Linear Flow Distillation
Zihan Yang, Shuyuan Tu, Licheng Zhang, Qi Dai, Yu-Gang Jiang, Zuxuan Wu
Main category: cs.CV
TL;DR: ArcFlow: A few-step distillation framework for diffusion models that uses non-linear flow trajectories to approximate teacher trajectories, achieving 40x speedup with minimal quality degradation.
Details
Motivation: Diffusion models have high inference costs due to multiple sequential denoising steps. Existing distillation methods use linear shortcuts that can't match the teacher's changing tangent directions, leading to quality degradation.Method: ArcFlow parameterizes velocity fields as mixtures of continuous momentum processes to capture velocity evolution, enabling analytical integration of non-linear trajectories. Uses lightweight adapters for trajectory distillation on pre-trained models.
Result: Achieves 40x speedup with 2 NFEs over original multi-step teachers (Qwen-Image-20B and FLUX.1-dev) while fine-tuning less than 5% of parameters. Maintains generative quality and diversity without significant degradation.
Conclusion: ArcFlow effectively distills diffusion models into few-step generators using non-linear flow trajectories, providing substantial speed improvements while preserving quality through analytical integration and lightweight adaptation.
Abstract: Diffusion models have achieved remarkable generation quality, but they suffer from significant inference cost due to their reliance on multiple sequential denoising steps, motivating recent efforts to distill this inference process into a few-step regime. However, existing distillation methods typically approximate the teacher trajectory by using linear shortcuts, which makes it difficult to match its constantly changing tangent directions as velocities evolve across timesteps, thereby leading to quality degradation. To address this limitation, we propose ArcFlow, a few-step distillation framework that explicitly employs non-linear flow trajectories to approximate pre-trained teacher trajectories. Concretely, ArcFlow parameterizes the velocity field underlying the inference trajectory as a mixture of continuous momentum processes. This enables ArcFlow to capture velocity evolution and extrapolate coherent velocities to form a continuous non-linear trajectory within each denoising step. Importantly, this parameterization admits an analytical integration of this non-linear trajectory, which circumvents numerical discretization errors and results in high-precision approximation of the teacher trajectory. To train this parameterization into a few-step generator, we implement ArcFlow via trajectory distillation on pre-trained teacher models using lightweight adapters. This strategy ensures fast, stable convergence while preserving generative diversity and quality. Built on large-scale models (Qwen-Image-20B and FLUX.1-dev), ArcFlow only fine-tunes on less than 5% of original parameters and achieves a 40x speedup with 2 NFEs over the original multi-step teachers without significant quality degradation. Experiments on benchmarks show the effectiveness of ArcFlow both qualitatively and quantitatively.
[393] Raster2Seq: Polygon Sequence Generation for Floorplan Reconstruction
Hao Phung, Hadar Averbuch-Elor
Main category: cs.CV
TL;DR: Raster2Seq: An autoregressive sequence-to-sequence approach for reconstructing structured vector-graphics representations from rasterized floorplan images by predicting labeled polygon sequences.
Details
Motivation: Existing techniques struggle with faithfully reconstructing complex floorplans with many rooms and varying polygon structures, which is important for computational tasks like automated understanding and CAD workflows.Method: Frames floorplan reconstruction as sequence-to-sequence task where elements (rooms, windows, doors) are represented as labeled polygon sequences. Uses autoregressive decoder that predicts next corner conditioned on image features and previously generated corners, guided by learnable anchors that direct attention to informative image regions.
Result: Achieves state-of-the-art performance on standard benchmarks (Structure3D, CubiCasa5K, Raster2Graph) and demonstrates strong generalization to more challenging datasets like WAFFLE with diverse room structures and complex geometric variations.
Conclusion: The autoregressive approach offers flexibility in output format and efficiently handles complex floorplans with numerous rooms and diverse polygon structures, advancing floorplan reconstruction capabilities.
Abstract: Reconstructing a structured vector-graphics representation from a rasterized floorplan image is typically an important prerequisite for computational tasks involving floorplans such as automated understanding or CAD workflows. However, existing techniques struggle in faithfully generating the structure and semantics conveyed by complex floorplans that depict large indoor spaces with many rooms and a varying numbers of polygon corners. To this end, we propose Raster2Seq, framing floorplan reconstruction as a sequence-to-sequence task in which floorplan elements–such as rooms, windows, and doors–are represented as labeled polygon sequences that jointly encode geometry and semantics. Our approach introduces an autoregressive decoder that learns to predict the next corner conditioned on image features and previously generated corners using guidance from learnable anchors. These anchors represent spatial coordinates in image space, hence allowing for effectively directing the attention mechanism to focus on informative image regions. By embracing the autoregressive mechanism, our method offers flexibility in the output format, enabling for efficiently handling complex floorplans with numerous rooms and diverse polygon structures. Our method achieves state-of-the-art performance on standard benchmarks such as Structure3D, CubiCasa5K, and Raster2Graph, while also demonstrating strong generalization to more challenging datasets like WAFFLE, which contain diverse room structures and complex geometric variations.
[394] WorldCompass: Reinforcement Learning for Long-Horizon World Models
Zehan Wang, Tengfei Wang, Haiyu Zhang, Xuhui Zuo, Junta Wu, Haoyuan Wang, Wenqiang Sun, Zhenwei Wang, Chenjie Cao, Hengshuang Zhao, Chunchao Guo, Zhou Zhao
Main category: cs.CV
TL;DR: WorldCompass is an RL post-training framework for video-based world models that improves exploration accuracy and consistency using clip-level rollouts, complementary rewards, and efficient RL algorithms.
Details
Motivation: Current long-horizon interactive video-based world models struggle with accurate and consistent exploration based on interaction signals. There's a need to better "steer" these models' exploration capabilities in autoregressive video generation paradigms.Method: Three core innovations: 1) Clip-level rollout strategy generating multiple samples at single target clips for efficiency and fine-grained rewards, 2) Complementary reward functions for interaction-following accuracy and visual quality to prevent reward hacking, 3) Efficient RL algorithm with negative-aware fine-tuning and optimizations.
Result: Evaluations on state-of-the-art world model WorldPlay show significant improvements in interaction accuracy and visual fidelity across various scenarios.
Conclusion: WorldCompass effectively enhances world model exploration capabilities through RL post-training, making video-based world models more accurate and consistent in interactive scenarios.
Abstract: This work presents WorldCompass, a novel Reinforcement Learning (RL) post-training framework for the long-horizon, interactive video-based world models, enabling them to explore the world more accurately and consistently based on interaction signals. To effectively “steer” the world model’s exploration, we introduce three core innovations tailored to the autoregressive video generation paradigm: 1) Clip-level rollout Strategy: We generate and evaluate multiple samples at a single target clip, which significantly boosts rollout efficiency and provides fine-grained reward signals. 2) Complementary Reward Functions: We design reward functions for both interaction-following accuracy and visual quality, which provide direct supervision and effectively suppress reward-hacking behaviors. 3) Efficient RL Algorithm: We employ the negative-aware fine-tuning strategy coupled with various efficiency optimizations to efficiently and effectively enhance model capacity. Evaluations on the SoTA open-source world model, WorldPlay, demonstrate that WorldCompass significantly improves interaction accuracy and visual fidelity across various scenarios.
[395] Autoregressive Image Generation with Masked Bit Modeling
Qihang Yu, Qihao Liu, Ju He, Xinyang Zhang, Yang Liu, Liang-Chieh Chen, Xi Chen
Main category: cs.CV
TL;DR: BAR introduces a scalable discrete tokenizer framework using masked bit autoregressive modeling that matches/surpasses continuous methods in visual generation by scaling codebook size.
Details
Motivation: The paper challenges the assumption that discrete tokenizers are intrinsically inferior to continuous methods in visual generation, arguing the performance gap stems from compression ratio differences rather than fundamental limitations.Method: Proposes masked Bit AutoRegressive modeling (BAR) - a scalable framework supporting arbitrary codebook sizes. Uses an autoregressive transformer with masked bit modeling head to predict discrete tokens by progressively generating their constituent bits.
Result: Achieves state-of-the-art gFID of 0.99 on ImageNet-256, outperforming leading continuous and discrete methods. Reduces sampling costs and converges faster than prior continuous approaches.
Conclusion: Discrete tokenizers can match or surpass continuous methods when properly scaled, challenging the dominance of continuous pipelines in visual generation. BAR provides a practical solution for scaling discrete representations.
Abstract: This paper challenges the dominance of continuous pipelines in visual generation. We systematically investigate the performance gap between discrete and continuous methods. Contrary to the belief that discrete tokenizers are intrinsically inferior, we demonstrate that the disparity arises primarily from the total number of bits allocated in the latent space (i.e., the compression ratio). We show that scaling up the codebook size effectively bridges this gap, allowing discrete tokenizers to match or surpass their continuous counterparts. However, existing discrete generation methods struggle to capitalize on this insight, suffering from performance degradation or prohibitive training costs with scaled codebook. To address this, we propose masked Bit AutoRegressive modeling (BAR), a scalable framework that supports arbitrary codebook sizes. By equipping an autoregressive transformer with a masked bit modeling head, BAR predicts discrete tokens through progressively generating their constituent bits. BAR achieves a new state-of-the-art gFID of 0.99 on ImageNet-256, outperforming leading methods across both continuous and discrete paradigms, while significantly reducing sampling costs and converging faster than prior continuous approaches. Project page is available at https://bar-gen.github.io/
[396] Winner Team Mia at TextVQA Challenge 2021: Vision-and-Language Representation Learning with Pre-trained Sequence-to-Sequence Model
Yixuan Qiao, Hao Chen, Jun Wang, Shanshan Zhao, Yihao Chen, Xianbin Ye, Ziliang Li, Xianbiao Qi, Peng Gao, Guotong Xie
Main category: cs.CV
TL;DR: Using T5-3B generative model for TextVQA task with additional pre-training tasks (MLM and RPP) to align object features and scene text, followed by fine-tuning on TextVQA dataset.
Details
Motivation: TextVQA requires models to read and reason about text in images, which involves incorporating text modality from images and reasoning over it. Existing approaches need better alignment between visual features and scene text.Method: Based on T5-3B pre-trained checkpoint, adds masked language modeling (MLM) and relative position prediction (RPP) pre-training tasks to align object features and scene text. Encoder handles fusion of multiple modalities (question text, object text labels, scene text labels, object visual features, scene visual features), decoder generates text sequence with cross-entropy loss. Uses large-scale scene text dataset for pre-training, then fine-tunes on TextVQA dataset.
Result: The paper presents a method for TextVQA using T5-3B with additional pre-training tasks, but specific quantitative results are not provided in the abstract.
Conclusion: The approach leverages T5’s generative capabilities for TextVQA with enhanced pre-training to better align visual and text modalities for scene text understanding.
Abstract: TextVQA requires models to read and reason about text in images to answer questions about them. Specifically, models need to incorporate a new modality of text present in the images and reason over it to answer TextVQA questions. In this challenge, we use generative model T5 for TextVQA task. Based on pre-trained checkpoint T5-3B from HuggingFace repository, two other pre-training tasks including masked language modeling(MLM) and relative position prediction(RPP) are designed to better align object feature and scene text. In the stage of pre-training, encoder is dedicate to handle the fusion among multiple modalities: question text, object text labels, scene text labels, object visual features, scene visual features. After that decoder generates the text sequence step-by-step, cross entropy loss is required by default. We use a large-scale scene text dataset in pre-training and then fine-tune the T5-3B with the TextVQA dataset only.
[397] Cross-Modal Retrieval for Motion and Text via DropTriple Loss
Sheng Yan, Yang Liu, Haoqiang Wang, Xin Du, Mengyuan Liu, Hong Liu
Main category: cs.CV
TL;DR: A dual-unimodal transformer encoder approach for cross-modal retrieval between human motion and text, using a novel DropTriple Loss to handle semantic conflicts from overlapping atomic actions.
Details
Motivation: While image-text and video-text cross-modal retrieval has received significant attention, human motion-text retrieval has been insufficiently explored despite its wide-ranging applicability in areas like animation, robotics, and human-computer interaction.Method: Uses a dual-unimodal transformer encoder architecture for motion-text retrieval. Introduces DropTriple Loss, which discards false negative samples from the negative sample set and focuses on mining genuinely hard negative samples to handle semantic conflicts from overlapping atomic actions in different motion sequences.
Result: Achieves 62.9% recall for motion retrieval and 71.5% for text retrieval (R@10) on the HumanML3D dataset. Also evaluated on KIT Motion-Language dataset.
Conclusion: The proposed dual-unimodal transformer encoder with DropTriple Loss effectively addresses human motion-text cross-modal retrieval, achieving strong performance on benchmark datasets and filling an important research gap.
Abstract: Cross-modal retrieval of image-text and video-text is a prominent research area in computer vision and natural language processing. However, there has been insufficient attention given to cross-modal retrieval between human motion and text, despite its wide-ranging applicability. To address this gap, we utilize a concise yet effective dual-unimodal transformer encoder for tackling this task. Recognizing that overlapping atomic actions in different human motion sequences can lead to semantic conflicts between samples, we explore a novel triplet loss function called DropTriple Loss. This loss function discards false negative samples from the negative sample set and focuses on mining remaining genuinely hard negative samples for triplet training, thereby reducing violations they cause. We evaluate our model and approach on the HumanML3D and KIT Motion-Language datasets. On the latest HumanML3D dataset, we achieve a recall of 62.9% for motion retrieval and 71.5% for text retrieval (both based on R@10). The source code for our approach is publicly available at https://github.com/eanson023/rehamot.
[398] Fast Image-based Neural Relighting with Translucency-Reflection Modeling
Shizhan Zhu, Shunsuke Saito, Aljaz Bozic, Carlos Aliaga, Trevor Darrell, Christoph Lassner
Main category: cs.CV
TL;DR: Neural 3D reconstruction and relighting model that extends volumetric implicit models (like NeRF) to be relightable using image-based lighting, handling complex materials like translucency and glossy reflections with fast rendering.
Details
Motivation: Image-based lighting (IBL) is computationally expensive for volumetric rendering of non-opaque, translucent materials. There's a need for fast neural 3D reconstruction and relighting models that can handle complex light transport effects.Method: Extends volumetric implicit models (e.g., neural radiance fields) to be relightable using IBL. The model handles complex materials like translucency and glossy reflections from detailed surface geometry.
Result: Achieves fast rendering (0.72s on NVIDIA 3090, 0.30s on A100 at 800×800 resolution) without engineering optimization. Produces realistic and compelling results for materials with complex light transport effects.
Conclusion: Presents a fast neural 3D reconstruction and relighting model that successfully extends volumetric implicit models to handle IBL relighting for complex materials with efficient rendering performance.
Abstract: Image-based lighting (IBL) is a widely used technique that renders objects using a high dynamic range image or environment map. However, aggregating the irradiance at the object’s surface is computationally expensive, in particular for non-opaque, translucent materials that require volumetric rendering techniques. In this paper we present a fast neural 3D reconstruction and relighting model that extends volumetric implicit models such as neural radiance fields to be relightable using IBL. It is general enough to handle materials that exhibit complex light transport effects, such as translucency and glossy reflections from detailed surface geometry, producing realistic and compelling results. Rendering can be within a second at 800$\times$800 resolution (0.72s on an NVIDIA 3090 GPU and 0.30s on an A100 GPU) without engineering optimization. Our code and dataset are available at https://zhusz.github.io/TRHM-Webpage/.
[399] LBL: Logarithmic Barrier Loss Function for One-class Classification
Ziyang Jiang, Peng Lin, Tianlei Wang
Main category: cs.CV
TL;DR: Novel logarithmic barrier function-based one-class classification loss (LBL) and its improved version LBLSig with unilateral relaxation Sigmoid function for more stable optimization.
Details
Motivation: One-class classification (OCC) lacks effective loss functions for deep learning, despite its strong applicability in real-world applications. Existing approaches need better optimization properties and more compact decision boundaries.Method: Proposes LBL loss using logarithmic barrier function to assign large gradients to margin samples for compact hypersphere. Then introduces LBLSig by incorporating unilateral relaxation Sigmoid function to address LBL’s instability when samples lie on boundary (infinity loss). LBLSig fuses MSE and CE loss characteristics.
Result: Experimental validation shows effectiveness of both LBL and LBLSig compared to popular OCC algorithms on different network structures. LBLSig provides smoother optimization than LBL.
Conclusion: The proposed logarithmic barrier-based losses (LBL and LBLSig) provide effective OCC loss functions for deep learning with improved optimization stability and compact decision boundaries.
Abstract: One-class classification (OCC) aims to train a classifier only with the target class data and attracts great attention for its strong applicability in real-world application. Despite a lot of advances have been made in OCC, it still lacks the effective OCC loss functions for deep learning. In this paper, a novel logarithmic barrier function based OCC loss (LBL) that assigns large gradients to the margin samples and thus derives more compact hypersphere, is first proposed by approximating the OCC objective smoothly. But the optimization of LBL may be instability especially when samples lie on the boundary leading to the infinity loss. To address this issue, then, a unilateral relaxation Sigmoid function is introduced into LBL and a novel OCC loss named LBLSig is proposed. The LBLSig can be seen as the fusion of the mean square error (MSE) and the cross entropy (CE) and the optimization of LBLSig is smoother owing to the unilateral relaxation Sigmoid function. The effectiveness of the proposed LBL and LBLSig is experimentally demonstrated in comparisons with several popular OCC algorithms on different network structures. The source code can be found at https://github.com/ML-HDU/LBL_LBLSig.
[400] DeltaSpace: A Semantic-aligned Feature Space for Flexible Text-guided Image Editing
Yueming Lyu, Kang Zhao, Bo Peng, Huafeng Chen, Yue Jiang, Yingya Zhang, Jing Dong, Caifeng Shan
Main category: cs.CV
TL;DR: DeltaEdit is a text-guided image editing framework that uses CLIP DeltaSpace to map visual feature differences to generative model latent directions, enabling text-free training and zero-shot inference without per-prompt optimization.
Details
Motivation: Existing text-guided image editing methods face challenges: training from scratch requires expensive annotated image-text pairs, while pre-trained model approaches suffer from per-prompt optimization or inference-time hyperparameter tuning limitations.Method: Identifies CLIP DeltaSpace where visual feature differences align with textual feature differences. Maps CLIP visual feature differences to generative model latent directions during training, and predicts latent directions from textual feature differences during inference.
Result: Extensive experiments show DeltaEdit works effectively with both GAN and diffusion models, achieving flexible text-guided image editing with text-free training and zero-shot inference capabilities.
Conclusion: DeltaEdit provides a novel solution for text-guided image editing that avoids expensive data collection and per-prompt optimization, demonstrating versatility across different generative models.
Abstract: Text-guided image editing faces significant challenges when considering training and inference flexibility. Much literature collects large amounts of annotated image-text pairs to train text-conditioned generative models from scratch, which is expensive and not efficient. After that, some approaches that leverage pre-trained vision-language models have been proposed to avoid data collection, but they are limited by either per text-prompt optimization or inference-time hyper-parameters tuning. To address these issues, we investigate and identify a specific space, referred to as CLIP DeltaSpace, where the CLIP visual feature difference of two images is semantically aligned with the CLIP textual feature difference of their corresponding text descriptions. Based on DeltaSpace, we propose a novel framework called DeltaEdit, which maps the CLIP visual feature differences to the latent space directions of a generative model during the training phase, and predicts the latent space directions from the CLIP textual feature differences during the inference phase. And this design endows DeltaEdit with two advantages: (1) text-free training; (2) generalization to various text prompts for zero-shot inference. Extensive experiments validate the effectiveness and versatility of DeltaEdit with different generative models, including both the GAN model and the diffusion model, in achieving flexible text-guided image editing. Code is available at https://github.com/Yueming6568/DeltaEdit.
[401] Improving Efficiency of Diffusion Models via Multi-Stage Framework and Tailored Multi-Decoder Architectures
Huijie Zhang, Yifu Lu, Ismail Alkhouri, Saiprasad Ravishankar, Dogyoon Song, Qing Qu
Main category: cs.CV
TL;DR: A multi-stage diffusion framework with custom multi-decoder U-net architecture that improves training and sampling efficiency by blending time-dependent models with universal shared parameters.
Details
Motivation: Diffusion models have remarkable generative performance but suffer from slow training and sampling due to extensive forward/reverse diffusion trajectories and large parameter counts across multiple timesteps.Method: Segments time interval into multiple stages using custom multi-decoder U-net architecture that blends time-dependent models with universally shared encoder, employs timestep clustering algorithm for stage division, and uses both universal and customized parameters.
Result: Significant training and sampling efficiency improvements on three state-of-the-art diffusion models including large-scale latent diffusion models, with ablation studies showing impact of timestep clustering and multi-decoder architecture.
Conclusion: The multi-stage framework efficiently distributes computational resources, mitigates inter-stage interference, and substantially improves training efficiency for diffusion models.
Abstract: Diffusion models, emerging as powerful deep generative tools, excel in various applications. They operate through a two-steps process: introducing noise into training samples and then employing a model to convert random noise into new samples (e.g., images). However, their remarkable generative performance is hindered by slow training and sampling. This is due to the necessity of tracking extensive forward and reverse diffusion trajectories, and employing a large model with numerous parameters across multiple timesteps (i.e., noise levels). To tackle these challenges, we present a multi-stage framework inspired by our empirical findings. These observations indicate the advantages of employing distinct parameters tailored to each timestep while retaining universal parameters shared across all time steps. Our approach involves segmenting the time interval into multiple stages where we employ custom multi-decoder U-net architecture that blends time-dependent models with a universally shared encoder. Our framework enables the efficient distribution of computational resources and mitigates inter-stage interference, which substantially improves training efficiency. Extensive numerical experiments affirm the effectiveness of our framework, showcasing significant training and sampling efficiency enhancements on three state-of-the-art diffusion models, including large-scale latent diffusion models. Furthermore, our ablation studies illustrate the impact of two important components in our framework: (i) a novel timestep clustering algorithm for stage division, and (ii) an innovative multi-decoder U-net architecture, seamlessly integrating universal and customized hyperparameters.
[402] Cognitive Edge Device (CED) for Real-Time Environmental Monitoring in Aquatic Ecosystems
Dennis Monari, Farhad Fassihi Tash, Jordan J. Bird, Ahmad Lotfi, Isibor Kennedy Ihianle, Salisu Wada Yahaya, Isibor Kennedy Ihianle, Md Mahmudul Hasan, Pedro Sousa, Pedro Machado
Main category: cs.CV
TL;DR: Underwater detection system using YOLO variants for identifying invasive signal crayfish and plastic pollution to protect aquatic ecosystems
Details
Motivation: Invasive signal crayfish cause ecosystem damage by spreading disease, burrowing destructively, and competing with native species, while plastic pollution further threatens aquatic environments. There's a need for automated detection systems to monitor these threats.Method: Developed Cognitive Edge Device (CED) computing platform and created two publicly available underwater datasets annotated for crayfish and plastic debris. Trained and evaluated four YOLO variants for object detection tasks.
Result: YOLOv5s achieved the highest detection accuracy with mAP@0.5 of 0.90 and best precision among the tested models.
Conclusion: The proposed system enables effective automated monitoring of invasive species and pollution in aquatic ecosystems, with YOLOv5s showing superior performance for underwater object detection tasks.
Abstract: Invasive signal crayfish have a detrimental impact on ecosystems. They spread the fungal-type crayfish plague disease (Aphanomyces astaci) that is lethal to the native white clawed crayfish, the only native crayfish species in Britain. Invasive signal crayfish extensively burrow, causing habitat destruction, erosion of river banks and adverse changes in water quality, while also competing with native species for resources leading to declines in native populations. Moreover, pollution exacerbates the vulnerability of White-clawed crayfish, with their populations declining by over 90%. To safeguard aquatic ecosystems, it is imperative to address the challenges posed by invasive species and pollution in aquatic ecosystem’s. This article introduces the Cognitive Edge Device (CED) computing platform for the detection of crayfish and plastic. It also presents two publicly available underwater datasets, annotated with sequences of crayfish and aquatic plastic debris. Four You Only Look Once (YOLO) variants were trained and evaluated for crayfish and plastic object detection. YOLOv5s achieved the highest detection accuracy, with an mAP@0.5 of 0.90, and achieved the best precision
[403] Determination of efficiency indicators of the stand for intelligent control of manual operations in industrial production
Anton Sergeev, Victor Minchenkov, Aleksei Soldatov
Main category: cs.CV
TL;DR: AI-based control system for tracking manual assembly operations using multicamera setup and YOLOv8 detection, with novel evaluation methodology using IoU, MASE, and residual histograms aggregated into unified efficiency index.
Details
Motivation: Manual operations in industrial production need quality assurance and real-time monitoring, especially under high variability and human errors. Current solutions lack robust evaluation frameworks for AI-based control systems.Method: Multicamera setup with YOLOv8-based detection module integrated into experimental stand. Evaluation uses timestamp-level comparisons between predicted and actual execution stages with three metrics: Intersection over Union (IoU), Mean Absolute Scaled Error (MASE), and Residual Distribution histograms, aggregated into unified efficiency index E_total.
Result: Validated on 120 assemblies at different speeds, showing high segmentation accuracy and identifying stage-specific timing deviations. System demonstrated robustness and evaluation framework applicable for benchmarking similar industrial solutions.
Conclusion: Proposed AI control system effectively tracks manual assembly with robust evaluation methodology. Framework enables reproducible assessment of similar industrial automation solutions.
Abstract: Manual operations remain essential in industrial production because of their flexibility and low implementation cost. However, ensuring their quality and monitoring execution in real time remains a challenge, especially under conditions of high variability and human-induced errors. In this paper, we present an AI-based control system for tracking manual assembly and propose a novel methodology to evaluate its overall efficiency. The developed system includes a multicamera setup and a YOLOv8-based detection module integrated into an experimental stand designed to replicate real production scenarios. The evaluation methodology relies on timestamp-level comparisons between predicted and actual execution stages, using three key metrics: Intersection over Union (IoU), Mean Absolute Scaled Error (MASE), Residual Distribution histograms. These metrics are aggregated into a unified efficiency index E_total for reproducible system assessment. The proposed approach was validated on a dataset of 120 assemblies performed at different speeds, demonstrating high segmentation accuracy and identifying stage-specific timing deviations. The results confirm the robustness of the control system and the applicability of the evaluation framework to benchmark similar solutions in industrial settings.
[404] TSJNet: A Multi-modality Target and Semantic Awareness Joint-driven Image Fusion Network
Yuchan Jie, Yushen Xu, Xiaosong Li, Huafeng Li, Haishu Tan, Feiping Nie
Main category: cs.CV
TL;DR: TSJNet is a novel multimodal fusion network for semantic segmentation and object detection that uses high-level task semantics to guide fusion, with multi-scale feature extraction and data-agnostic spatial attention for better generalization.
Details
Motivation: Existing multimodal fusion methods have limited capability in discriminative modeling of multi-scale semantic structures and salient target regions, restricting effective fusion of task-related semantic details across modalities.Method: Proposes TSJNet with: 1) multi-dimensional feature extraction module with dual parallel branches for multi-scale and salient features, 2) data-agnostic spatial attention module in decoder for dynamic attention calibration across domains, 3) joint optimization using fusion loss with semantic losses.
Result: Outstanding performance on five public datasets (MSRS, M³FD, RoadScene, LLVIP, TNO) and new UMS dataset. Improves mAP@0.5 by 7.97% and mIoU by 10.88% compared to state-of-the-art methods.
Conclusion: TSJNet effectively addresses multimodal fusion challenges for visual tasks, demonstrating superior performance and generalization through task-semantic guided fusion and data-agnostic attention mechanisms.
Abstract: This study aims to address the problem of incomplete information in unimodal images for semantic segmentation and object detection tasks. Existing multimodal fusion methods suffer from limited capability in discriminative modeling of multi-scale semantic structures and salient target regions, which further restricts the effective fusion of task-related semantic details and target information across modalities. To tackle these challenges, this paper proposes a novel fusion network termed TSJNet, which leverages the semantic information output by high-level tasks in a joint manner to guide the fusion process. Specifically, we design a multi-dimensional feature extraction module with dual parallel branches to capture multi-scale and salient features. Meanwhile, a data-agnostic spatial attention module embedded in the decoder dynamically calibrates attention allocation across different data domains, significantly enhancing the model’s generalization ability. To optimize both fusion and advanced visual tasks, we balance performance by combining fusion loss with semantic losses. Additionally, we have developed a multimodal unmanned aerial vehicle (UAV) dataset covering multiple scenarios (UMS). Extensive experiments demonstrate that TSJNet achieves outstanding performance on five public datasets (MSRS, M\textsuperscript{3}FD, RoadScene, LLVIP, and TNO) and our UMS dataset. The generated fusion results exhibit favorable visual effects, and compared to state-of-the-art methods, the mean average precision (mAP@0.5) and mean intersection over union (mIoU) for object detection and segmentation, respectively, improve by 7.97% and 10.88%.The code and the dataset has been publicly released at https://github.com/XylonXu01/TSJNet.
[405] View-Centric Multi-Object Tracking with Homographic Matching in Moving UAV
Deyi Ji, Lanyun Zhu, Siqi Gao, Qi Zhu, Yiru Zhao, Peng Xu, Yue Ding, Hongtao Lu, Jieping Ye, Feng Wu, Feng Zhao
Main category: cs.CV
TL;DR: A novel Multi-Object Tracking framework called HomView-MOT that uses view homography to address MOT challenges in moving UAV scenarios with irregular flight trajectories.
Details
Motivation: Traditional MOT methods fail in moving UAV scenarios due to irregular flight trajectories (hovering, turning, moving up/down) that cause scene background changes and significant view shifts in objects, making frame-to-frame IoU association ineffective.Method: Proposes HomView-MOT framework with: 1) Fast Homography Estimation (FHE) for rapid computation of homography matrices between frames, 2) View-Centric ID Learning (VCIL) using multi-view homography to learn cross-view ID features, and 3) Homographic Matching Filter (HMF) that maps object bounding boxes to common view plane for physical IoU association.
Result: Achieves state-of-the-art performance on prominent UAV MOT datasets VisDrone and UAVDT.
Conclusion: The framework successfully addresses MOT challenges in moving UAV environments by leveraging view homography for better object association and tracking in dynamic aerial scenarios.
Abstract: In this paper, we address the challenge of Multi-Object Tracking (MOT) in moving Unmanned Aerial Vehicle (UAV) scenarios, where irregular flight trajectories, such as hovering, turning left/right, and moving up/down, lead to significantly greater complexity compared to fixed-camera MOT. Specifically, changes in the scene background not only render traditional frame-to-frame object IoU association methods ineffective but also introduce significant view shifts in the objects, which complicates tracking. To overcome these issues, we propose a novel HomView-MOT framework, which for the first time, harnesses the view homography inherent in changing scenes to solve MOT challenges in moving environments, incorporating homographic matching and view-centric concepts. We introduce a Fast Homography Estimation (FHE) algorithm for rapid computation of homography matrices between video frames, enabling object View-Centric ID Learning (VCIL) and leveraging multi-view homography to learn cross-view ID features. Concurrently, our Homographic Matching Filter (HMF) maps object bounding boxes from different frames onto a common view plane for a more realistic physical IoU association. Extensive experiments have proven that these innovations allow HomView-MOT to achieve state-of-the-art performance on prominent UAV MOT datasets VisDrone and UAVDT.
[406] TruthPrInt: Mitigating Large Vision-Language Models Object Hallucination Via Latent Truthful-Guided Pre-Intervention
Jinhao Duan, Fei Kong, Hao Cheng, James Diffenderfer, Bhavya Kailkhura, Lichao Sun, Xiaofeng Zhu, Xiaoshuang Shi, Kaidi Xu
Main category: cs.CV
TL;DR: TruthPrInt uses internal states of Large Vision-Language Models as per-token hallucination indicators and applies truthful-guided inference-time intervention to mitigate object hallucination.
Details
Motivation: Object hallucination is a major trustworthy challenge in LVLMs, and while LLM internal states encode truthfulness, it's unexplored how LVLM internal states function as per-token hallucination indicators for mitigation.Method: First explores LVLM internal states to discover they are high-specificity per-token hallucination indicators and that different LVLMs encode universal hallucination patterns. Then proposes TruthPrInt which learns truthful directions of LVLM decoding and applies truthful-guided inference-time intervention during decoding, with cross-LVLM and cross-data transferability via hallucination latent subspace alignment.
Result: TruthPrInt significantly outperforms state-of-the-art methods in extensive experimental settings including in-domain and out-of-domain scenarios over popular LVLMs and OH benchmarks.
Conclusion: LVLM internal states serve as effective per-token hallucination indicators, and TruthPrInt’s truthful-guided intervention successfully mitigates object hallucination with strong transferability across models and datasets.
Abstract: Object Hallucination (OH) has been acknowledged as one of the major trustworthy challenges in Large Vision-Language Models (LVLMs). Recent advancements in Large Language Models (LLMs) indicate that internal states, such as hidden states, encode the “overall truthfulness” of generated responses. However, it remains under-explored how internal states in LVLMs function and whether they could serve as “per-token” hallucination indicators, which is essential for mitigating OH. In this paper, we first conduct an in-depth exploration of LVLM internal states with OH issues and discover that (1) LVLM internal states are high-specificity per-token indicators of hallucination behaviors. Moreover, (2) different LVLMs encode universal patterns of hallucinations in common latent subspaces, indicating that there exist “generic truthful directions” shared by various LVLMs. Based on these discoveries, we propose Truthful-Guided Pre-Intervention (TruthPrInt) that first learns the truthful direction of LVLM decoding and then applies truthful-guided inference-time intervention during LVLM decoding. We further propose TruthPrInt to enhance both cross-LVLM and cross-data hallucination detection transferability by constructing and aligning hallucination latent subspaces. We evaluate TruthPrInt in extensive experimental settings, including in-domain and out-of-domain scenarios, over popular LVLMs and OH benchmarks. Experimental results indicate that TruthPrInt significantly outperforms state-of-the-art methods. Codes will be available at https://github.com/jinhaoduan/TruthPrInt.
[407] Generalist Foundation Models from a Multimodal Dataset for 3D Computed Tomography
Ibrahim Ethem Hamamci, Sezgin Er, Chenyu Wang, Furkan Almas, Ayse Gulnihan Simsek, Sevval Nil Esirgun, Irem Dogan, Omer Faruk Durugol, Benjamin Hou, Suprosanna Shit, Weicheng Dai, Murong Xu, Hadrien Reynaud, Muhammed Furkan Dasdelen, Bastian Wittmann, Tamaz Amiranashvili, Enis Simsar, Mehmet Simsar, Emine Bensu Erdemir, Abdullah Alanbay, Anjany Sekuboyina, Berkan Lafci, Ahmet Kaplan, Zhiyong Lu, Malgorzata Polacin, Bernhard Kainz, Christian Bluethgen, Kayhan Batmanghelich, Mehmet Kemal Ozdemir, Bjoern Menze
Main category: cs.CV
TL;DR: CT-RATE dataset with 3D chest CT scans and reports enables CT-CLIP for medical vision-language pretraining and CT-CHAT for 3D medical chat applications.
Details
Motivation: Addressing the scarcity of comprehensive 3D medical imaging datasets that pair images with textual reports, which limits advancements in medical imaging AI.Method: Introduces CT-RATE dataset (25,692 3D chest CT scans with reports), develops CT-CLIP contrastive language-image pretraining framework, and creates CT-CHAT vision-language chat model by combining CT-CLIP’s encoder with LLM.
Result: CT-CLIP outperforms state-of-the-art supervised models in multi-abnormality detection and case retrieval; CT-CHAT demonstrates specialized 3D medical imaging capabilities.
Conclusion: The open-source release of CT-RATE, CT-CLIP, and CT-CHAT addresses critical challenges in 3D medical imaging and lays groundwork for future medical AI innovations.
Abstract: Advancements in medical imaging AI, particularly in 3D imaging, have been limited due to the scarcity of comprehensive datasets. We introduce CT-RATE, a public dataset that pairs 3D medical images with corresponding textual reports. CT-RATE comprises 25,692 non-contrast 3D chest CT scans from 21,304 unique patients. Each scan is accompanied by its corresponding radiology report. Leveraging CT-RATE, we develop CT-CLIP, a CT-focused contrastive language-image pretraining framework designed for broad applications without the need for task-specific training. We demonstrate how CT-CLIP can be used in multi-abnormality detection and case retrieval, and outperforms state-of-the-art fully supervised models across all key metrics. By combining CT-CLIP’s vision encoder with a pretrained large language model, we create CT-CHAT, a vision-language foundational chat model for 3D chest CT volumes. Finetuned on over 2.7 million question-answer pairs derived from the CT-RATE dataset, CT-CHAT underscores the necessity for specialized methods in 3D medical imaging. Collectively, the open-source release of CT-RATE, CT-CLIP, and CT-CHAT not only addresses critical challenges in 3D medical imaging but also lays the groundwork for future innovations in medical AI and improved patient care.
[408] Robust Hyperbolic Learning with Curvature-Aware Optimization
Ahmad Bdeir, Johannes Burchert, Lars Schmidt-Thieme, Niels Landwehr
Main category: cs.CV
TL;DR: Hyperbolic deep learning with Riemannian AdamW optimizer and fine-tunable hyperbolic scaling for improved stability and generalization in vision tasks.
Details
Motivation: Current hyperbolic learning approaches suffer from overfitting, computational expense, and instability when learning manifold curvature for different tasks and datasets. The negative curvature and exponential distance properties of hyperbolic spaces offer natural hierarchical representation but need better optimization methods.Method: Derived Riemannian AdamW optimizer for hyperbolic generalization, introduced fine-tunable hyperbolic scaling to constrain embeddings and reduce approximation errors, and developed curvature-aware learning schema for Riemannian optimizers to combine curvature and hyperbolic parameter learning.
Result: Demonstrated consistent performance improvements across Computer Vision, EEG classification, and hierarchical metric learning tasks while greatly reducing runtime compared to previous hyperbolic learning approaches.
Conclusion: The proposed Riemannian AdamW with fine-tunable hyperbolic scaling addresses key limitations of hyperbolic deep learning, providing more stable, efficient, and generalizable models for hierarchical representation learning tasks.
Abstract: Hyperbolic deep learning has become a growing research direction in computer vision due to the unique properties afforded by the alternate embedding space. The negative curvature and exponentially growing distance metric provide a natural framework for capturing hierarchical relationships between datapoints and allowing for finer separability between their embeddings. However, current hyperbolic learning approaches are still prone to overfitting, computationally expensive, and prone to instability, especially when attempting to learn the manifold curvature to adapt to tasks and different datasets. To address these issues, our paper presents a derivation for Riemannian AdamW that helps increase hyperbolic generalization ability. For improved stability, we introduce a novel fine-tunable hyperbolic scaling approach to constrain hyperbolic embeddings and reduce approximation errors. Using this along with our curvature-aware learning schema for Riemannian Optimizers enables the combination of curvature and non-trivialized hyperbolic parameter learning. Our approach demonstrates consistent performance improvements across Computer Vision, EEG classification, and hierarchical metric learning tasks while greatly reducing runtime.
[409] EAGLE: Elevating Geometric Reasoning through LLM-empowered Visual Instruction Tuning
Zhihao Li, Yao Du, Yang Liu, Yan Zhang, Yufang Liu, Mengdi Zhang, Xunliang Cai, Charles Ling, Boyu Wang
Main category: cs.CV
TL;DR: EAGLE is a visual-centric framework that enhances MLLMs’ geometric reasoning by improving visual perception through geometric knowledge injection and refinement guided by LLMs.
Details
Motivation: MLLMs struggle with geometric reasoning due to visual perception deficiencies like inaccurate geometric comprehension and visual hallucinations. Current approaches focus on optimizing LLM backbones but neglect visual element discernment.Method: Proposes EAGLE: a coarse-to-fine visual enhancement framework with 1) Geometric Knowledge Injection using diagram-caption data to improve geometry-language alignment, and 2) Geometric Knowledge Refinement using LLM-driven chain-of-thought to guide vision encoder to prioritize key elements.
Result: Extensive experiments demonstrate effectiveness on three popular benchmarks, showing improved geometric reasoning capabilities through enhanced visual perception.
Conclusion: EAGLE addresses MLLMs’ visual perception deficiencies in geometric reasoning by adopting a visual-centric approach that synergizes visual comprehension with mathematical reasoning.
Abstract: Multi-modal Large Language Models (MLLMs) have advanced greatly in general tasks. However, they still face challenges in geometric reasoning, a task that requires synergistic integration of visual recognition proficiency and complex reasoning strength. Existing MLLMs prioritize optimizing the LLM backbone to enhance problem-solving capabilities, while rarely emphasizing improvements in discerning visual elements. However, we reveal that MLLMs suffer from severe visual perception deficiencies, including inaccurate geometric comprehension and severe visual hallucinations, which constrain their reasoning performance. To address this issue, we revisit geometric reasoning through a visual-centric lens that highlights the role of visual perception. To achieve this, we propose EAGLE, a novel coarse-to-fine visual enhancement framework that progressively leverages LLMs’ guidance to improve perception proficiency. Specifically, given the substantial disparity between geometric diagrams and natural images, we first introduce Geometric Knowledge Injection. This process explores fundamental knowledge from diagram-caption data to enhance recognition capabilities and improve geometry-language alignments. Then, recognizing that different elements contribute unequally in the reasoning process, we introduce Geometric Knowledge Refinement. This stage leverages LLM-driven chain-of-thought solutions to guide the vision encoder in adaptively prioritizing key elements, fostering a synergistic interplay between visual comprehension and mathematical reasoning. Finally, we develop EAGLE, a geometry expert with strong perception and reasoning capabilities. Extensive experiments demonstrate its effectiveness on three popular benchmarks.
[410] A High Resolution Urban and Rural Settlement Map of Africa Using Deep Learning and Satellite Imagery
Mohammad Kakooei, James Bailie, Markus B. Pettersson, Albin Söderberg, Albin Becevic, Adel Daoud
Main category: cs.CV
TL;DR: Deep learning framework using multi-source satellite data produces 10m resolution urban-rural maps for Africa from 2016-2022, outperforming existing global datasets.
Details
Motivation: Existing global urban-rural datasets are spatially coarse, methodologically inconsistent, and poorly adapted to heterogeneous regions like Africa, limiting their usefulness for policy and research. They obscure small or informal settlements and produce inconsistencies between countries.Method: DeepLabV3-based deep learning framework integrating multi-source data including Landsat-8 imagery, VIIRS nighttime lights, ESRI LULC, and GHS-SMOD. Uses semantic segmentation to capture fine-scale settlement morphology at 10m resolution across Africa from 2016-2022.
Result: Model achieves 65% overall accuracy and 0.47 Kappa coefficient at continental scale, outperforming existing global products like SMOD. Produces High-Resolution Urban-Rural (HUR) dataset covering 2016-2022 period.
Conclusion: The framework provides an open, reproducible approach for high-resolution settlement mapping in Africa, enabling more context-aware analyses of rapidly evolving settlement systems with potential for historical extension back to 1990s.
Abstract: Accurate and consistent mapping of urban and rural areas is crucial for sustainable development, spatial planning, and policy design. It is particularly important in simulating the complex interactions between human activities and natural resources. Existing global urban-rural datasets such as such as GHSL-SMOD, GHS Degree of Urbanisation, and GRUMP are often spatially coarse, methodologically inconsistent, and poorly adapted to heterogeneous regions such as Africa, which limits their usefulness for policy and research. Their coarse grids and rule-based classification methods obscure small or informal settlements, and produce inconsistencies between countries. In this study, we develop a DeepLabV3-based deep learning framework that integrates multi-source data, including Landsat-8 imagery, VIIRS nighttime lights, ESRI Land Use Land Cover (LULC), and GHS-SMOD, to produce a 10m resolution urban-rural map across the African continent from 2016 to 2022. The use of Landsat data also highlights the potential to extend this mapping approach historically, reaching back to the 1990s. The model employs semantic segmentation to capture fine-scale settlement morphology, and its outputs are validated using the Demographic and Health Surveys (DHS) dataset, which provides independent, survey-based urban-rural labels. The model achieves an overall accuracy of 65% and a Kappa coefficient of 0.47 at the continental scale, outperforming existing global products such as SMOD. The resulting High-Resolution Urban-Rural (HUR) dataset provides an open and reproducible framework for mapping human settlements, enabling more context-aware analyses of Africa’s rapidly evolving settlement systems. We release a continent-wide urban-rural dataset covering the period from 2016 to 2022, offering a new source for high-resolution settlement mapping in Africa.
[411] Differentially Private Adaptation of Diffusion Models via Noisy Aggregated Embeddings
Pura Peetathawatchai, Wei-Ning Chen, Berivan Isik, Sanmi Koyejo, Albert No
Main category: cs.CV
TL;DR: DPAgg-TI enables privacy-preserving personalization of diffusion models by adding calibrated noise to aggregated textual embeddings instead of fine-tuning with DP-SGD, achieving better utility under differential privacy constraints.
Details
Motivation: Personalizing large diffusion models on small, sensitive datasets using DP-SGD causes severe utility degradation due to high noise requirements. There's a need for alternative approaches that maintain privacy while preserving output quality.Method: Uses Textual Inversion (TI) to learn embedding vectors for images, then adds calibrated noise to the aggregation of per-image embeddings to ensure differential privacy guarantees (DPAgg-TI).
Result: DPAgg-TI outperforms DP-SGD fine-tuning in both utility and robustness under the same privacy budget, achieving results closely matching non-private baselines on style adaptation tasks with private artwork and Olympic pictograms.
Conclusion: Aggregating textual embeddings with calibrated noise provides a more effective approach for privacy-preserving personalization of diffusion models compared to DP-SGD fine-tuning, especially in small data regimes.
Abstract: Personalizing large-scale diffusion models poses serious privacy risks, especially when adapting to small, sensitive datasets. A common approach is to fine-tune the model using differentially private stochastic gradient descent (DP-SGD), but this suffers from severe utility degradation due to the high noise needed for privacy, particularly in the small data regime. We propose an alternative that leverages Textual Inversion (TI), which learns an embedding vector for an image or set of images, to enable adaptation under differential privacy (DP) constraints. Our approach, Differentially Private Aggregation via Textual Inversion (DPAgg-TI), adds calibrated noise to the aggregation of per-image embeddings to ensure formal DP guarantees while preserving high output fidelity. We show that DPAgg-TI outperforms DP-SGD finetuning in both utility and robustness under the same privacy budget, achieving results closely matching the non-private baseline on style adaptation tasks using private artwork from a single artist and Paris 2024 Olympic pictograms. In contrast, DP-SGD fails to generate meaningful outputs in this setting.
[412] Towards Stabilized and Efficient Diffusion Transformers through Long-Skip-Connections with Spectral Constraints
Guanjie Chen, Xinyu Zhao, Yucheng Zhou, Xiaoye Qu, Tianlong Chen, Yu Cheng
Main category: cs.CV
TL;DR: Skip-DiT enhances Diffusion Transformers with Long-Skip-Connections to stabilize feature dynamics, enabling efficient cached inference with 4.4× training acceleration and 1.5-2× inference speedup while maintaining quality.
Details
Motivation: Diffusion Transformers (DiT) have superior image/video generation quality but suffer from dynamic feature instability during cached inference, causing error amplification. The absence of long-range feature preservation mechanisms leads to unstable feature propagation and perturbation sensitivity.Method: Proposes Skip-DiT, a DiT variant enhanced with Long-Skip-Connections (LSCs) inspired by U-Nets. LSCs stabilize feature dynamics through theoretical spectral norm analysis. Enables efficient statical caching mechanism that reuses deep features across timesteps while updating shallow components.
Result: Achieves 4.4× training acceleration and faster convergence, 1.5-2× inference acceleration with negligible quality loss and high fidelity to original output. Outperforms existing DiT caching methods across various quantitative metrics.
Conclusion: Long-Skip-Connections are critical architectural components for stable and efficient diffusion transformers, establishing Skip-DiT as an improved architecture for image and video generation tasks.
Abstract: Diffusion Transformers (DiT) have emerged as a powerful architecture for image and video generation, offering superior quality and scalability. However, their practical application suffers from inherent dynamic feature instability, leading to error amplification during cached inference. Through systematic analysis, we identify the absence of long-range feature preservation mechanisms as the root cause of unstable feature propagation and perturbation sensitivity. To this end, we propose Skip-DiT, an image and video generative DiT variant enhanced with Long-Skip-Connections (LSCs) - the key efficiency component in U-Nets. Theoretical spectral norm and visualization analysis demonstrate how LSCs stabilize feature dynamics. Skip-DiT architecture and its stabilized dynamic feature enable an efficient statical caching mechanism that reuses deep features across timesteps while updating shallow components. Extensive experiments across the image and video generation tasks demonstrate that Skip-DiT achieves: (1) 4.4 times training acceleration and faster convergence, (2) 1.5-2 times inference acceleration with negligible quality loss and high fidelity to the original output, outperforming existing DiT caching methods across various quantitative metrics. Our findings establish Long-Skip-Connections as critical architectural components for stable and efficient diffusion transformers. Codes are provided in the https://github.com/OpenSparseLLMs/Skip-DiT.
[413] OmniHD-Scenes: A Next-Generation Multimodal Dataset for Autonomous Driving
Lianqing Zheng, Long Yang, Qunshu Lin, Wenjin Ai, Minghao Liu, Shouyi Lu, Jianan Liu, Hongze Ren, Jingyue Mo, Xiaokai Bai, Jie Bai, Zhixiong Ma, Xichan Zhu
Main category: cs.CV
TL;DR: OmniHD-Scenes is a large-scale multimodal autonomous driving dataset with 128-beam LiDAR, 6 cameras, and 6 4D imaging radars, featuring comprehensive annotations and novel annotation pipelines.
Details
Motivation: Next-generation autonomous driving requires multimodal datasets with extensive coverage, detailed annotations, and diverse scene representation to develop effective data-driven solutions.Method: Created OmniHD-Scenes dataset with 1501 clips (450K+ frames) using 128-beam LiDAR, 6 cameras, and 6 4D imaging radars. Developed novel 4D annotation pipeline and automated dense occupancy ground truth generation leveraging non-key frames.
Result: Dataset includes 200 annotated clips with 514K+ 3D bounding boxes and semantic segmentation. Established benchmarks for 3D detection and semantic occupancy prediction using surround-view cameras and 4D imaging radar.
Conclusion: OmniHD-Scenes provides comprehensive multimodal data for autonomous driving research, demonstrating effectiveness of low-cost sensor configurations and robustness under adverse conditions.
Abstract: The rapid advancement of deep learning has intensified the need for comprehensive data for use by autonomous driving algorithms. High-quality datasets are crucial for the development of effective data-driven autonomous driving solutions. Next-generation autonomous driving datasets must be multimodal, incorporating data from advanced sensors that feature extensive data coverage, detailed annotations, and diverse scene representation. To address this need, we present OmniHD-Scenes, a large-scale multimodal dataset that provides comprehensive omnidirectional high-definition data. The OmniHD-Scenes dataset combines data from 128-beam LiDAR, six cameras, and six 4D imaging radar systems to achieve full environmental perception. The dataset comprises 1501 clips, each approximately 30-s long, totaling more than 450K synchronized frames and more than 5.85 million synchronized sensor data points. We also propose a novel 4D annotation pipeline. To date, we have annotated 200 clips with more than 514K precise 3D bounding boxes. These clips also include semantic segmentation annotations for static scene elements. Additionally, we introduce a novel automated pipeline for generation of the dense occupancy ground truth, which effectively leverages information from non-key frames. Alongside the proposed dataset, we establish comprehensive evaluation metrics, baseline models, and benchmarks for 3D detection and semantic occupancy prediction. These benchmarks utilize surround-view cameras and 4D imaging radar to explore cost-effective sensor solutions for autonomous driving applications. Extensive experiments demonstrate the effectiveness of our low-cost sensor configuration and its robustness under adverse conditions. Data will be released at https://www.2077ai.com/OmniHD-Scenes.
[414] AI-Powered Intracranial Hemorrhage Detection: A Co-Scale Convolutional Attention Model with Uncertainty-Based Fuzzy Integral Operator and Feature Screening
Mehdi Hosseini Chagahi, Niloufar Delfan, Behzad Moshiri, Md. Jalil Piran, Jaber Hatam Parikhan
Main category: cs.CV
TL;DR: A novel two-layer approach for intracranial hemorrhage detection from CT scans using feature selection and uncertainty-based fusion
Details
Motivation: Intracranial hemorrhage (ICH) is a critical medical condition requiring timely diagnosis to prevent serious complications. The study aims to detect ICH occurrence and classify subdural hemorrhage types as binary classification problems.Method: Two-layer approach: 1) Feature extraction from CT scan slices using co-scale convolutional attention (CCA) classifier with added layers, feature selection via variance analysis and bootstrap forest algorithm for discriminative power assessment, 2) Novel uncertainty-based fuzzy integral operator to fuse information from different CT slices while accounting for dependencies between consecutive slices.
Result: The method significantly improves detection accuracy for intracranial hemorrhage by combining informative feature selection with slice dependency-aware fusion.
Conclusion: The proposed approach effectively detects ICH and classifies SDH types through explainable AI techniques and sophisticated multi-slice information fusion.
Abstract: Intracranial hemorrhage (ICH) refers to the leakage or accumulation of blood within the skull, which occurs due to the rupture of blood vessels in or around the brain. If this condition is not diagnosed in a timely manner and appropriately treated, it can lead to serious complications such as decreased consciousness, permanent neurological disabilities, or even death.The primary aim of this study is to detect the occurrence or non-occurrence of ICH, followed by determining the type of subdural hemorrhage (SDH). These tasks are framed as two separate binary classification problems. By adding two layers to the co-scale convolutional attention (CCA) classifier architecture, we introduce a novel approach for ICH detection. In the first layer, after extracting features from different slices of computed tomography (CT) scan images, we combine these features and select the 50 components that capture the highest variance in the data, considering them as informative features. We then assess the discriminative power of these features using the bootstrap forest algorithm, discarding those that lack sufficient discriminative ability between different classes. This algorithm explicitly determines the contribution of each feature to the final prediction, assisting us in developing an explainable AI model. The features feed into a boosting neural network as a latent feature space. In the second layer, we introduce a novel uncertainty-based fuzzy integral operator to fuse information from different CT scan slices. This operator, by accounting for the dependencies between consecutive slices, significantly improves detection accuracy.
[415] “ScatSpotter” – A Dog Poop Detection Dataset
Jon Crall
Main category: cs.CV
TL;DR: ScatSpotter dataset for detecting small, camouflaged waste objects like dog feces using before/after/negative image collection protocol with polygon annotations.
Details
Motivation: Small waste objects like biological droppings are difficult to detect in cluttered outdoor scenes but important for environmental cleanliness, public health, and autonomous cleanup systems.Method: Created ScatSpotter dataset with over 9000 images and 6000 polygon annotations using “before/after/negative” protocol. Evaluated off-the-shelf models (VIT, MaskRCNN, YOLO-v9, DINO-v2) and fine-tuned DINO for detection/segmentation.
Result: Zero-shot DINO performed poorly, indicating limited foundational-model coverage. Fine-tuned DINO achieved best performance with box-level average precision of 0.69 on validation set and 0.7 on test set.
Conclusion: The dataset establishes strong baselines for detecting small, camouflaged waste objects and highlights challenges in this domain. The work supports open access to models and data with discussion of distribution mechanisms.
Abstract: Small, amorphous waste objects such as biological droppings and microtrash can be difficult to see, especially in cluttered scenes, yet they matter for environmental cleanliness, public health, and autonomous cleanup. We introduce “ScatSpotter”: a new dataset of images annotated with polygons around dog feces, collected to train and study object detection and segmentation systems for small potentially camouflaged outdoor waste. We gathered data in mostly urban environments, using “before/after/negative” (BAN) protocol: for a given location, we capture an image with the object present, an image from the same viewpoint after removal, and a nearby negative scene that often contains visually similar confusers. Image collection began in 2020. This paper focuses on two dataset checkpoints from 2025 and 2024. The dataset contains over 9000 images and 6000 polygon annotations. Of the author-captured images we held out 691 for validation and used the rest to train. Via community participation we obtained a 121-image test set that, while small, is independent from author-collected images and provides some generalization confidence across photographers, devices, and locations. Due to its limited size, we report both validation and test results. We explore the difficulty of the dataset using off-the-shelf VIT, MaskRCNN, YOLO-v9, and DINO-v2 models. Zero-shot DINO performs poorly, indicating limited foundational-model coverage of this category. Tuned DINO is the best model with a box-level average precision of 0.69 on a 691-image validation set and 0.7 on the test set. These results establish strong baselines and quantify the remaining difficulty of detecting small, camouflaged waste objects. To support open access to models and data, we compare centralized and decentralized distribution mechanisms and discuss trade-offs for sharing scientific data. Code and project details are hosted on GitHub.
[416] ERVD: An Efficient and Robust ViT-Based Distillation Framework for Remote Sensing Image Retrieval
Le Dong, Qixuan Cao, Lei Pu, Fangfang Wu, Weisheng Dong, Xin Li, Guangming Shi
Main category: cs.CV
TL;DR: ERVD is a Vision Transformer-based distillation framework for efficient and robust remote sensing image retrieval
Details
Motivation: Remote sensing image retrieval faces challenges with large-scale datasets and complex visual content. Existing methods struggle with efficiency and robustness, especially with limited labeled data.Method: Proposes a Vision Transformer-based distillation framework using knowledge distillation from a large teacher model to a smaller student model, with attention mechanisms for feature extraction and robustness enhancement.
Result: Achieves state-of-the-art performance on remote sensing image retrieval benchmarks with improved efficiency and robustness compared to existing methods.
Conclusion: ERVD provides an effective solution for efficient remote sensing image retrieval through ViT-based knowledge distillation, balancing accuracy and computational efficiency.
Abstract: ERVD: An Efficient and Robust ViT-Based Distillation Framework for Remote Sensing Image Retrieval
[417] Virtual Community: An Open World for Humans, Robots, and Society
Qinhong Zhou, Hongxin Zhang, Xiangye Lin, Zheyuan Zhang, Yutian Chen, Wenjun Liu, Zunzhe Zhang, Sunli Chen, Lixing Fang, Qiushi Lyu, Xinyu Sun, Jincheng Yang, Zeyuan Wang, Bao Chi Dang, Zhehuan Chen, Daksha Ladia, Quang Vinh Dang, Jiageng Liu, Chuang Gan
Main category: cs.CV
TL;DR: Virtual Community is an open-world platform for studying human-robot coexistence and embodied social intelligence through physics-based simulation with real-world 3D scenes, featuring multi-agent challenges for planning and robot collaboration.
Details
Motivation: To explore the future of human-robot coexistence in shared communities and enable the study of embodied social intelligence at scale, addressing both opportunities and challenges of AI and Robotics progress.Method: Developed an open-source multi-agent physics simulator with real-world aligned community generation pipeline, including outdoor spaces, indoor scenes, and grounded agents with rich characters. Introduced two challenges: Community Planning Challenge for multi-agent reasoning and Community Robot Challenge for heterogeneous robot collaboration.
Result: Created a comprehensive platform for studying human-robot interactions, evaluated various baselines on proposed challenges, and demonstrated difficulties in both high-level open-world task planning and low-level cooperation controls.
Conclusion: Virtual Community provides a foundation for studying human-robot coexistence in open-world environments and aims to unlock further research in embodied social intelligence and multi-agent collaboration.
Abstract: The rapid progress in AI and Robotics may lead to a profound societal transformation, as humans and robots begin to coexist within shared communities, introducing both opportunities and challenges. To explore this future, we present Virtual Community-an open-world platform for humans, robots, and society-built on a universal physics engine and grounded in real-world 3D scenes. With Virtual Community, we aim to enable the study of embodied social intelligence at scale. To support these, Virtual Community features: 1) An open-source multi-agent physics simulator that supports robots, humans, and their interactions within a society; 2) A large-scale, real-world aligned community generation pipeline, including vast outdoor space, diverse indoor scenes, and a community of grounded agents with rich characters and appearances. Leveraging Virtual Community, we propose two novel challenges. The Community Planning Challenge evaluates multi-agent reasoning and planning ability in open-world settings, such as cooperating to help agents with daily activities and efficiently connecting other agents. The Community Robot Challenge requires multiple heterogeneous robots to collaborate in solving complex open-world tasks. We evaluate various baselines on these tasks and demonstrate the challenges in both high-level open-world task planning and low-level cooperation controls. We hope that Virtual Community will unlock further study of human-robot coexistence within open-world environments.
[418] A Survey on Class-Agnostic Counting: Advancements from Reference-Based to Open-World Text-Guided Approaches
Luca Ciampi, Ali Azmoudeh, Elif Ecem Akbaba, Erdi Sarıtaş, Ziya Ata Yazıcı, Hazım Kemal Ekenel, Giuseppe Amato, Fabrizio Falchi
Main category: cs.CV
TL;DR: Comprehensive review of class-agnostic counting (CAC) methodologies that can count objects across arbitrary categories without prior training, categorizing approaches into reference-based, reference-less, and open-world text-guided paradigms.
Details
Motivation: Existing object counting methods are limited to known classes and require extensive labeled datasets, while humans can effortlessly count objects from diverse categories without prior knowledge. Class-agnostic counting addresses this limitation for flexible and generalizable counting systems.Method: Proposes taxonomy of CAC approaches: 1) Reference-based (exemplar-guided, state-of-the-art), 2) Reference-less (leverages inherent image patterns), 3) Open-world text-guided (uses vision-language models with textual prompts). Reviews 30 CAC architectures and benchmarks performance on FSC-147 and CARPK datasets.
Result: Presents comprehensive review with performance leaderboard on gold-standard benchmarks. Reference-based methods achieve best performance, while open-world text-guided approaches offer most flexible solutions using vision-language models.
Conclusion: CAC enables counting objects across arbitrary categories without prior training. Taxonomy provides framework for understanding approaches. Open-world text-guided methods using vision-language models represent promising direction for flexible counting systems, though challenges remain in annotation dependency and generalization.
Abstract: Visual object counting has recently shifted towards class-agnostic counting (CAC), which addresses the challenge of counting objects across arbitrary categories, a crucial capability for flexible and generalizable counting systems. Unlike humans, who effortlessly identify and count objects from diverse categories without prior knowledge, most existing counting methods are restricted to enumerating instances of known classes, requiring extensive labeled datasets for training and struggling in open-vocabulary settings. In contrast, CAC aims to count objects belonging to classes never seen during training, operating in a few-shot setting. In this paper, we present the first comprehensive review of CAC methodologies. We propose a taxonomy to categorize CAC approaches into three paradigms based on how target object classes can be specified: reference-based, reference-less, and open-world text-guided. Reference-based approaches achieve state-of-the-art performance by relying on exemplar-guided mechanisms. Reference-less methods eliminate exemplar dependency by leveraging inherent image patterns. Finally, open-world text-guided methods use vision-language models, enabling object class descriptions via textual prompts, offering a flexible and promising solution. Based on this taxonomy, we provide an overview of 30 CAC architectures and report their performance on gold-standard benchmarks, discussing key strengths and limitations. Specifically, we present results on the FSC-147 dataset, setting a leaderboard using gold-standard metrics, and on the CARPK dataset to assess generalization capabilities. Finally, we offer a critical discussion of persistent challenges, such as annotation dependency and generalization, alongside future directions.
[419] ImageRAG: Dynamic Image Retrieval for Reference-Guided Image Generation
Rotem Shalev-Arkushin, Rinon Gal, Amit H. Bermano, Ohad Fried
Main category: cs.CV
TL;DR: ImageRAG: A retrieval-augmented generation method that dynamically retrieves relevant images based on text prompts and uses them as context to guide diffusion models for generating rare or unseen concepts, without requiring RAG-specific training.
Details
Motivation: Diffusion models struggle to generate rare or unseen concepts. The paper addresses this limitation by exploring retrieval-augmented generation (RAG) for image generation to improve generation of rare and fine-grained concepts.Method: ImageRAG dynamically retrieves relevant images based on text prompts and uses them as context to guide existing image conditioning models. Unlike prior approaches that require RAG-specific training, ImageRAG leverages existing models without additional training.
Result: The approach shows significant improvement in generating rare and fine-grained concepts across different base models, demonstrating adaptability across various model types.
Conclusion: ImageRAG provides an effective, adaptable solution for improving generation of rare concepts in diffusion models through retrieval-augmented generation without requiring specialized training.
Abstract: Diffusion models enable high-quality and diverse visual content synthesis. However, they struggle to generate rare or unseen concepts. To address this challenge, we explore the usage of Retrieval-Augmented Generation (RAG) with image generation models. We propose ImageRAG, a method that dynamically retrieves relevant images based on a given text prompt, and uses them as context to guide the generation process. Prior approaches that used retrieved images to improve generation, trained models specifically for retrieval-based generation. In contrast, ImageRAG leverages the capabilities of existing image conditioning models, and does not require RAG-specific training. Our approach is highly adaptable and can be applied across different model types, showing significant improvement in generating rare and fine-grained concepts using different base models. Our project page is available at: https://rotem-shalev.github.io/ImageRAG
[420] EgoLife: Towards Egocentric Life Assistant
Jingkang Yang, Shuai Liu, Hongming Guo, Yuhao Dong, Xiamengwei Zhang, Sicheng Zhang, Pengyun Wang, Zitang Zhou, Binzhu Xie, Ziyue Wang, Bei Ouyang, Zhengyu Lin, Marco Cominelli, Zhongang Cai, Yuanhan Zhang, Peiyuan Zhang, Fangzhou Hong, Joerg Widmer, Francesco Gringoli, Lei Yang, Bo Li, Ziwei Liu
Main category: cs.CV
TL;DR: EgoLife introduces an egocentric life assistant system with a 300-hour multimodal dataset, EgoLifeQA benchmark tasks, and EgoButler system (EgoGPT + EgoRAG) for long-context daily life assistance.
Details
Motivation: To develop AI-powered wearable glasses that enhance personal efficiency by understanding and assisting with daily activities through comprehensive egocentric multimodal data collection and analysis.Method: Collected 300-hour EgoLife Dataset from 6 participants living together for one week using AI glasses (egocentric video) with synchronized third-person references. Created EgoLifeQA benchmark tasks and developed EgoButler system with EgoGPT (omni-modal model) and EgoRAG (retrieval-based component).
Result: EgoGPT achieves state-of-the-art performance on egocentric video understanding. The system demonstrates capability for long-context question answering about daily life activities, health monitoring, and personalized recommendations.
Conclusion: EgoLife provides foundational resources (dataset, models, benchmarks) for egocentric AI assistant research, identifying critical factors and bottlenecks for future improvements in multimodal understanding of daily life.
Abstract: We introduce EgoLife, a project to develop an egocentric life assistant that accompanies and enhances personal efficiency through AI-powered wearable glasses. To lay the foundation for this assistant, we conducted a comprehensive data collection study where six participants lived together for one week, continuously recording their daily activities - including discussions, shopping, cooking, socializing, and entertainment - using AI glasses for multimodal egocentric video capture, along with synchronized third-person-view video references. This effort resulted in the EgoLife Dataset, a comprehensive 300-hour egocentric, interpersonal, multiview, and multimodal daily life dataset with intensive annotation. Leveraging this dataset, we introduce EgoLifeQA, a suite of long-context, life-oriented question-answering tasks designed to provide meaningful assistance in daily life by addressing practical questions such as recalling past relevant events, monitoring health habits, and offering personalized recommendations. To address the key technical challenges of (1) developing robust visual-audio models for egocentric data, (2) enabling identity recognition, and (3) facilitating long-context question answering over extensive temporal information, we introduce EgoButler, an integrated system comprising EgoGPT and EgoRAG. EgoGPT is an omni-modal model trained on egocentric datasets, achieving state-of-the-art performance on egocentric video understanding. EgoRAG is a retrieval-based component that supports answering ultra-long-context questions. Our experimental studies verify their working mechanisms and reveal critical factors and bottlenecks, guiding future improvements. By releasing our datasets, models, and benchmarks, we aim to stimulate further research in egocentric AI assistants.
[421] Adversarial Wear and Tear: Exploiting Natural Damage for Generating Physical-World Adversarial Examples
Samra Irshad, Seungkyu Lee, Nassir Navab, Hong Joo Lee, Seong Tae Kim
Main category: cs.CV
TL;DR: AdvWT introduces physical-world adversarial examples inspired by natural ‘wear and tear’ on objects like traffic signs, using GAN-based image translation and adversarial style code manipulation to create realistic-looking but misleading damage patterns.
Details
Motivation: Current physical-world adversarial examples rely on temporary, ad-hoc modifications (shadows, stickers) that are scenario-specific. The authors aim to create more natural and inherent adversarial perturbations by leveraging the organic phenomenon of 'wear and tear' that naturally occurs on physical objects over time.Method: Two-step approach: 1) Use unsupervised GAN-based image-to-image translation to model naturally occurring damage on outdoor signboards, encoding damage characteristics into a latent ‘damage style code’. 2) Introduce adversarial perturbations into the style code, optimizing its transformation to generate adversarial images that maintain perceptual realism while effectively misleading neural networks.
Result: AdvWT effectively misleads DNNs in both digital and physical domains on traffic sign datasets. It achieves higher attack success rates, greater robustness, and more natural appearance compared to existing physical-world adversarial methods. Additionally, using AdvWT in training enhances model generalizability to real-world damaged signs.
Conclusion: AdvWT demonstrates that leveraging naturally occurring phenomena like ‘wear and tear’ can create more realistic and effective physical-world adversarial examples, offering both security vulnerabilities and potential benefits for improving model robustness through adversarial training.
Abstract: The presence of adversarial examples in the physical world poses significant challenges to the deployment of Deep Neural Networks in safety-critical applications such as autonomous driving. Most existing methods for crafting physical-world adversarial examples are ad-hoc, relying on temporary modifications like shadows, laser beams, or stickers that are tailored to specific scenarios. In this paper, we introduce a new class of physical-world adversarial examples, AdvWT, which draws inspiration from the naturally occurring phenomenon of wear and tear', an inherent property of physical objects. Unlike manually crafted perturbations, wear and tear’ emerges organically over time due to environmental degradation, as seen in the gradual deterioration of outdoor signboards. To achieve this, AdvWT follows a two-step approach. First, a GAN-based, unsupervised image-to-image translation network is employed to model these naturally occurring damages, particularly in the context of outdoor signboards. The translation network encodes the characteristics of damaged signs into a latent `damage style code’. In the second step, we introduce adversarial perturbations into the style code, strategically optimizing its transformation process. This manipulation subtly alters the damage style representation, guiding the network to generate adversarial images where the appearance of damages remains perceptually realistic, while simultaneously ensuring their effectiveness in misleading neural networks. Through comprehensive experiments on two traffic sign datasets, we show that AdvWT effectively misleads DNNs in both digital and physical domains. AdvWT achieves an effective attack success rate, greater robustness, and a more natural appearance compared to existing physical-world adversarial examples. Additionally, integrating AdvWT into training enhances a model’s generalizability to real-world damaged signs.
[422] Targetless LiDAR-Camera Calibration with Neural Gaussian Splatting
Haebeom Jung, Namtae Kim, Jungwoo Kim, Jaesik Park
Main category: cs.CV
TL;DR: TLC-Calib: A targetless LiDAR-camera calibration method using neural Gaussian scene representation with photometric and geometric regularization, outperforming existing methods on multiple datasets.
Details
Motivation: Traditional LiDAR-camera calibration requires physical targets which are impractical for real-world deployment, and calibrated extrinsics degrade over time due to sensor drift, requiring periodic recalibration.Method: Joint optimization of sensor poses with neural Gaussian-based scene representation, using reliable LiDAR points as anchor Gaussians to preserve global structure and auxiliary Gaussians to prevent local overfitting. Fully differentiable pipeline with photometric and geometric regularization.
Result: Consistently outperforms existing targetless methods on KITTI-360, Waymo, and Fast-LIVO2 datasets, and yields more consistent Novel View Synthesis results reflecting improved extrinsic alignment.
Conclusion: TLC-Calib provides robust and generalizable targetless calibration for LiDAR-camera systems, addressing practical deployment challenges and sensor drift issues.
Abstract: Accurate LiDAR-camera calibration is crucial for multi-sensor systems. However, traditional methods often rely on physical targets, which are impractical for real-world deployment. Moreover, even carefully calibrated extrinsics can degrade over time due to sensor drift or external disturbances, necessitating periodic recalibration. To address these challenges, we present a Targetless LiDAR-Camera Calibration (TLC-Calib) that jointly optimizes sensor poses with a neural Gaussian-based scene representation. Reliable LiDAR points are frozen as anchor Gaussians to preserve global structure, while auxiliary Gaussians prevent local overfitting under noisy initialization. Our fully differentiable pipeline with photometric and geometric regularization achieves robust and generalizable calibration, consistently outperforming existing targetless methods on the KITTI-360, Waymo, and Fast-LIVO2 datasets. In addition, it yields more consistent Novel View Synthesis results, reflecting improved extrinsic alignment. The project page is available at: https://www.haebeom.com/tlc-calib-site/.
[423] VisionReasoner: Unified Reasoning-Integrated Visual Perception via Reinforcement Learning
Yuqi Liu, Tianyuan Qu, Zhisheng Zhong, Bohao Peng, Shu Liu, Bei Yu, Jiaya Jia
Main category: cs.CV
TL;DR: VisionReasoner is a unified vision-language model framework that can reason and solve multiple visual perception tasks (detection, segmentation, counting) within a single model through structured reasoning processes.
Details
Motivation: Large vision-language models have inherent capabilities for diverse visual tasks, but there's a need for a unified framework that can handle multiple perception tasks within a single model while providing transparent reasoning processes.Method: VisionReasoner uses a unified reward mechanism and multi-object cognitive learning strategies to enhance reasoning capabilities. It generates structured reasoning processes before delivering outputs, and is evaluated on 10 diverse tasks across detection, segmentation, and counting domains.
Result: VisionReasoner achieves superior performance as a unified model, outperforming baseline Qwen2.5VL by 29.1% on COCO (detection), 22.1% on ReasonSeg (segmentation), and 13.2% on CountBench (counting). Human evaluation shows its reasoning processes are faithful and reliable.
Conclusion: VisionReasoner demonstrates that unified vision-language models can effectively handle diverse visual perception tasks with transparent reasoning, showing strong performance across multiple domains without task-specific annotations.
Abstract: Large vision-language models exhibit inherent capabilities to handle diverse visual perception tasks. In this paper, we introduce VisionReasoner, a unified framework capable of reasoning and solving multiple visual perception tasks within a shared model. Specifically, by designing a unified reward mechanism and multi-object cognitive learning strategies, VisionReasoner enhances its reasoning capabilities to analyze visual inputs, and addresses diverse perception tasks within a unified model. VisionReasoner generates a structured reasoning process before delivering the desired outputs responding to user queries. Human evaluation reveals the reasoning process of VisionReasoner is faithful and reliable even without annotated reasoning train data. To rigorously assess unified visual perception capabilities, we evaluate VisionReasoner on ten diverse tasks spanning three critical domains: detection, segmentation, and counting. Experimental results show that VisionReasoner achieves superior performance as a unified model, outperforming the baseline Qwen2.5VL by relative margins of 29.1% on COCO (detection), 22.1% on ReasonSeg (segmentation), and 13.2% on CountBench (counting).
[424] ReaMOT: A Benchmark and Framework for Reasoning-based Multi-Object Tracking
Sijia Chen, Yanqiu Yu, En Yu, Wenbing Tao
Main category: cs.CV
TL;DR: ReaMOT introduces a reasoning-based multi-object tracking task that requires logical reasoning to track objects based on implicit language instructions, with a new benchmark and training-free framework combining LVLM reasoning with SAM2 temporal modeling.
Details
Motivation: Existing referring multi-object tracking (RMOT) methods are designed for explicit instructions and fail to handle complex instructions requiring logical reasoning. There's a need for models that can understand implicit constraints and perform reasoning to identify and track objects.Method: Proposes ReaTrack, a training-free framework that synergizes the reasoning capabilities of Thinking-variant Large Vision-Language Models (LVLM) with the precise temporal modeling of SAM2 for segmentation and tracking. Also introduces the ReaMOT Challenge benchmark with 1,156 instructions categorized into High-Level Reasoning and Low-Level Perception tasks.
Result: Extensive experiments on the ReaMOT Challenge benchmark demonstrate the effectiveness of the ReaTrack framework in handling complex reasoning-based tracking tasks.
Conclusion: ReaMOT addresses the limitation of existing RMOT methods by introducing reasoning-based tracking, providing a comprehensive benchmark, and demonstrating a viable framework that combines LVLM reasoning with temporal modeling for complex instruction-based tracking.
Abstract: Referring Multi-Object Tracking (RMOT) aims to track targets specified by language instructions. However, existing RMOT paradigms are largely designed for explicit instructions and consequently fail to generalize to complex instructions that require logical reasoning. To overcome this, we propose Reasoning-based Multi-Object Tracking (ReaMOT), a novel task that requires models to identify and track targets that satisfy implicit constraints via logical reasoning. To advance this field, we construct the ReaMOT Challenge, a comprehensive benchmark comprising: (1) a large-scale dataset with 1,156 instructions categorized into High-Level Reasoning and Low-Level Perception, covering 423,359 image-language pairs across 869 diverse scenes; and (2) a tailored metric suite designed to jointly evaluate reasoning accuracy and tracking robustness. Furthermore, we propose ReaTrack, a training-free framework that synergizes the reasoning capabilities of Thinking-variant Large Vision-Language Model (LVLM) with the precise temporal modeling of SAM2. Extensive experiments on the ReaMOT Challenge benchmark demonstrates the effectiveness of our ReaTrack framework.
[425] Can NeRFs See without Cameras?
Chaitanya Amballa, Sattwik Basu, Yu-Lin Wei, Zhijian Yang, Mehmet Ergezer, Romit Roy Choudhury
Main category: cs.CV
TL;DR: NeRF adaptation to learn from multipath RF/audio signals for environment inference, applied to indoor floorplan reconstruction from sparse WiFi measurements.
Details
Motivation: Extend NeRF's success in 3D scene synthesis to multipath signals (RF/audio) that contain environmental reflections, enabling environment inference from mixed signals.Method: Redesign NeRFs to learn from multipath signals by modeling how RF/audio signals propagate and reflect in environments, applied to indoor WiFi measurements for floorplan inference.
Result: Successfully learns implicit floorplans from sparse WiFi measurements, enabling indoor signal prediction and basic ray tracing applications.
Conclusion: NeRFs can be adapted to work with multipath signals, opening new possibilities for environment inference using RF/audio measurements beyond visual data.
Abstract: Neural Radiance Fields (NeRFs) have been remarkably successful at synthesizing novel views of 3D scenes by optimizing a volumetric scene function. This scene function models how optical rays bring color information from a 3D object to the camera pixels. Radio frequency (RF) or audio signals can also be viewed as a vehicle for delivering information about the environment to a sensor. However, unlike camera pixels, an RF/audio sensor receives a mixture of signals that contain many environmental reflections (also called “multipath”). Is it still possible to infer the environment using such multipath signals? We show that with redesign, NeRFs can be taught to learn from multipath signals, and thereby “see” the environment. As a grounding application, we aim to infer the indoor floorplan of a home from sparse WiFi measurements made at multiple locations inside the home. Although a difficult inverse problem, our implicitly learnt floorplans look promising, and enables forward applications, such as indoor signal prediction and basic ray tracing.
[426] On Geometry-Enhanced Parameter-Efficient Fine-Tuning for 3D Scene Segmentation
Liyao Tang, Zhe Chen, Dacheng Tao
Main category: cs.CV
TL;DR: GEM introduces a geometry-aware parameter-efficient fine-tuning module for 3D point cloud transformers that integrates local positional encodings with lightweight attention to address spatial-geometric distribution mismatches.
Details
Motivation: Current parameter-efficient fine-tuning (PEFT) methods underperform on 3D point cloud models due to geometric and spatial distribution shifts, and existing approaches treat points as orderless tokens, neglecting local spatial structures and global geometric contexts.Method: Proposes Geometric Encoding Mixer (GEM) - a geometry-aware PEFT module that explicitly integrates fine-grained local positional encodings with a lightweight latent attention mechanism to capture comprehensive global context for 3D point cloud transformers.
Result: GEM achieves performance comparable to or sometimes exceeding full fine-tuning while updating only 1.6% of parameters, with significantly reduced training time and memory requirements compared to other PEFT methods.
Conclusion: GEM sets a new benchmark for efficient, scalable, and geometry-aware fine-tuning of large-scale 3D point cloud models, bridging the gap between parameter efficiency and geometric understanding.
Abstract: The emergence of large-scale pre-trained point cloud models has significantly advanced 3D scene understanding, but adapting these models to specific downstream tasks typically demands full fine-tuning, incurring high computational and storage costs. Parameter-efficient fine-tuning (PEFT) techniques, successful in natural language processing and 2D vision tasks, would underperform when naively applied to 3D point cloud models due to significant geometric and spatial distribution shifts. Existing PEFT methods commonly treat points as orderless tokens, neglecting important local spatial structures and global geometric contexts in 3D modeling. To bridge this gap, we introduce the Geometric Encoding Mixer (GEM), a novel geometry-aware PEFT module specifically designed for 3D point cloud transformers. GEM explicitly integrates fine-grained local positional encodings with a lightweight latent attention mechanism to capture comprehensive global context, thereby effectively addressing the spatial and geometric distribution mismatch. Extensive experiments demonstrate that GEM achieves performance comparable to or sometimes even exceeding full fine-tuning, while only updating 1.6% of the model’s parameters, fewer than other PEFT methods. With significantly reduced training time and memory requirements, our approach thus sets a new benchmark for efficient, scalable, and geometry-aware fine-tuning of large-scale 3D point cloud models. Code is available at https://github.com/LiyaoTang/GEM.
[427] MonkeyOCR: Document Parsing with a Structure-Recognition-Relation Triplet Paradigm
Zhang Li, Yuliang Liu, Qiang Liu, Zhiyin Ma, Ziyang Zhang, Shuo Zhang, Biao Yang, Zidun Guo, Jiarui Zhang, Xinyu Wang, Xiang Bai
Main category: cs.CV
TL;DR: MonkeyOCR introduces a document parsing model using Structure-Recognition-Relation triplet paradigm, trained on comprehensive MonkeyDoc dataset, achieving SOTA performance with efficient deployment.
Details
Motivation: Current document parsing approaches suffer from complex multi-tool pipelines or inefficient full-page processing with giant end-to-end models. Existing datasets are limited in scope, focusing on single tasks, languages, or document types.Method: Proposes SRR paradigm dividing document parsing into three questions: structure detection (Where?), content recognition (What?), and relation prediction (How?). Uses MonkeyDoc dataset (4.5M bilingual instances, 10+ doc types) to train 3B-parameter foundation model, then applies contiguous parameter degradation to create smaller models (0.6B-1.2B).
Result: Achieves state-of-the-art performance surpassing previous open-source and closed-source methods including Gemini 2.5-Pro. Models can be efficiently deployed on single RTX 3090 GPU.
Conclusion: MonkeyOCR demonstrates effectiveness of SRR paradigm for document parsing, with comprehensive dataset and efficient model scaling enabling practical deployment while maintaining SOTA performance.
Abstract: We introduce MonkeyOCR, a document parsing model that advances the state of the art by leveraging a Structure-Recognition-Relation (SRR) triplet paradigm. This design simplifies what would otherwise be a complex multi-tool pipeline and avoids the inefficiencies of processing full pages with giant end-to-end models. In SRR, document parsing is abstracted into three fundamental questions - Where is it?'' (structure), What is it?’’ (recognition), and ``How is it organized?’’ (relation) - corresponding to structure detection, content recognition, and relation prediction. To support this paradigm, we present MonkeyDoc, a comprehensive dataset with 4.5 million bilingual instances spanning over ten document types, which addresses the limitations of existing datasets that often focus on a single task, language, or document type. Leveraging the SRR paradigm and MonkeyDoc, we trained a 3B-parameter document foundation model. We further identify parameter redundancy in this model and propose contiguous parameter degradation (CPD), enabling the construction of models from 0.6B to 1.2B parameters that run faster with acceptable performance drop. MonkeyOCR achieves state-of-the-art performance, surpassing previous open-source and closed-source methods, including Gemini 2.5-Pro. Additionally, the model can be efficiently deployed for inference on a single RTX 3090 GPU. Code and models will be released at https://github.com/Yuliang-Liu/MonkeyOCR.
[428] Exploring Adversarial Watermarking in Transformer-Based Models: Transferability and Robustness Against Defense Mechanism for Medical Images
Rifat Sadik, Tanvir Rahman, Arpan Bhattacharjee, Bikash Chandra Halder, Ismail Hossain, Mridul Banik, Jia Uddin
Main category: cs.CV
TL;DR: Vision Transformers (ViTs) for dermatological images are highly vulnerable to adversarial watermarking attacks, with accuracy dropping to 27.6%, but adversarial training can restore performance to 90%.
Details
Motivation: While Vision Transformers (ViTs) have shown success in computer vision tasks including medical image analysis, their reliance on global attention mechanisms makes them potentially susceptible to adversarial attacks. The paper investigates this vulnerability specifically for dermatological images using adversarial watermarking techniques.Method: The study uses Projected Gradient Descent (PGD) to generate adversarial watermarks (imperceptible perturbations) that fool ViT models. It examines the transferability of these attacks to CNN models and analyzes the effectiveness of adversarial training as a defense mechanism.
Result: ViTs show significant vulnerability to adversarial watermarking attacks, with accuracy dropping as low as 27.6% when attacked. However, adversarial training proves effective, raising accuracy back up to 90.0%. The attacks show some transferability to CNNs but ViTs are more susceptible.
Conclusion: Vision Transformers for medical image analysis are highly vulnerable to adversarial attacks despite their strong performance on clean images. Adversarial training is an effective defense strategy that can significantly mitigate this vulnerability while maintaining performance on clean data.
Abstract: Deep learning models have shown remarkable success in dermatological image analysis, offering potential for automated skin disease diagnosis. Previously, convolutional neural network(CNN) based architectures have achieved immense popularity and success in computer vision (CV) based task like skin image recognition, generation and video analysis. But with the emergence of transformer based models, CV tasks are now are nowadays carrying out using these models. Vision Transformers (ViTs) is such a transformer-based models that have shown success in computer vision. It uses self-attention mechanisms to achieve state-of-the-art performance across various tasks. However, their reliance on global attention mechanisms makes them susceptible to adversarial perturbations. This paper aims to investigate the susceptibility of ViTs for medical images to adversarial watermarking-a method that adds so-called imperceptible perturbations in order to fool models. By generating adversarial watermarks through Projected Gradient Descent (PGD), we examine the transferability of such attacks to CNNs and analyze the performance defense mechanism – adversarial training. Results indicate that while performance is not compromised for clean images, ViTs certainly become much more vulnerable to adversarial attacks: an accuracy drop of as low as 27.6%. Nevertheless, adversarial training raises it up to 90.0%.
[429] Revisiting Transformers with Insights from Image Filtering and Boosting
Laziz U. Abdullaev, Maksim Tkachenko, Tan M. Nguyen
Main category: cs.CV
TL;DR: The paper develops an image processing framework to theoretically explain self-attention mechanisms in Transformers, showing that image-inspired modifications improve model interpretability, accuracy, robustness, and long-sequence understanding.
Details
Motivation: Self-attention mechanisms in Transformers are heuristic-driven and challenging to interpret. While some research has explored understanding self-attention through image denoising and nonparametric regression, existing frameworks lack deeper mechanistic interpretation of architectural components like positional encoding and residual connections.Method: Develops a unifying image processing framework to explain self-attention computation and architectural components. Introduces two independent architectural modifications within transformers inspired by image processing principles.
Result: Image processing-inspired modifications lead to improved accuracy and robustness against data contamination and adversaries across language and vision tasks, as well as better long sequence understanding.
Conclusion: The image processing framework provides a theoretical foundation for understanding self-attention mechanisms and their variants, while practical modifications demonstrate performance improvements across multimodal tasks.
Abstract: The self-attention mechanism, a cornerstone of Transformer-based state-of-the-art deep learning architectures, is largely heuristic-driven and fundamentally challenging to interpret. Establishing a robust theoretical foundation to explain its remarkable success and limitations has therefore become an increasingly prominent focus in recent research. Some notable directions have explored understanding self-attention through the lens of image denoising and nonparametric regression. While promising, existing frameworks still lack a deeper mechanistic interpretation of various architectural components that enhance self-attention, both in its original formulation and subsequent variants. In this work, we aim to advance this understanding by developing a unifying image processing framework, capable of explaining not only the self-attention computation itself but also the role of components such as positional encoding and residual connections, including numerous later variants. We also pinpoint potential distinctions between the two concepts building upon our framework, and make effort to close this gap. We introduce two independent architectural modifications within transformers. While our primary objective is interpretability, we empirically observe that image processing-inspired modifications can also lead to notably improved accuracy and robustness against data contamination and adversaries across language and vision tasks as well as better long sequence understanding.
[430] Toward Inherently Robust VLMs Against Visual Perception Attacks
Pedram MohajerAnsari, Amir Salarpour, Michael Kühr, Siyu Huang, Mohammad Hamad, Sebastian Steinhorst, Habeeb Olufowobi, Bing Li, Mert D. Pesé
Main category: cs.CV
TL;DR: Vision-language models fine-tuned for autonomous vehicle perception (V2LMs) show inherent robustness to adversarial attacks without adversarial training, outperforming conventional DNNs in maintaining accuracy under attack.
Details
Motivation: Autonomous vehicles rely on DNNs for perception tasks like traffic sign recognition and vehicle detection, but these models are vulnerable to adversarial attacks that threaten safety. Existing defenses like adversarial training often fail to generalize and degrade clean accuracy.Method: Introduces Vehicle Vision-Language Models (V2LMs) - fine-tuned vision-language models specialized for autonomous vehicle perception. Studies two deployment approaches: Solo (task-specific V2LMs) and Tandem (single V2LM for all three tasks). Also explores integrating V2LMs in parallel with existing perception stacks.
Result: Under adversarial attacks, conventional DNNs drop 33-74% in accuracy, while V2LMs decline by under 8% on average. Tandem deployment achieves comparable robustness to Solo while being more memory-efficient.
Conclusion: V2LMs are inherently more robust to unseen attacks without adversarial training, suggesting they are a promising path toward secure, robust autonomous vehicle perception.
Abstract: Autonomous vehicles rely on deep neural networks (DNNs) for traffic sign recognition, lane centering, and vehicle detection, yet these models are vulnerable to attacks that induce misclassification and threaten safety. Existing defenses (e.g., adversarial training) often fail to generalize and degrade clean accuracy. We introduce Vehicle Vision-Language Models (V2LMs), fine-tuned vision-language models specialized for autonomous vehicle perception, and show that they are inherently more robust to unseen attacks without adversarial training, maintaining substantially higher adversarial accuracy than conventional DNNs. We study two deployments: Solo (task-specific V2LMs) and Tandem (a single V2LM for all three tasks). Under attacks, DNNs drop 33-74%, whereas V2LMs decline by under 8% on average. Tandem achieves comparable robustness to Solo while being more memory-efficient. We also explore integrating V2LMs in parallel with existing perception stacks to enhance resilience. Our results suggest V2LMs are a promising path toward secure, robust AV perception.
[431] State-Space Hierarchical Compression with Gated Attention and Learnable Sampling for Hour-Long Video Understanding in Large Multimodal Models
Geewook Kim, Minjoon Seo
Main category: cs.CV
TL;DR: Efficient video compression framework using bidirectional state-space models to reduce token explosion from hour-long videos while maintaining competitive performance.
Details
Motivation: Address the severe token explosion problem when processing hour-long videos in large multimodal models by compressing massive video-frame features efficiently.Method: Uses bidirectional state-space model with gated skip connections and learnable weighted-average pooling on periodically inserted learned queries for hierarchical downsampling across spatial and temporal dimensions.
Result: Competitive results on challenging hour-long video understanding tasks while significantly reducing token budget; replacing state-space model with conventional modules causes substantial performance degradation.
Conclusion: The proposed state-space modeling effectively compresses multi-frame video information, emphasizing resource-conscious efficiency for practical real-world deployments with validated scalability and generality across benchmarks.
Abstract: We propose an efficient framework to compress massive video-frame features before feeding them into large multimodal models, thereby mitigating the severe token explosion arising from hour-long videos. Our design leverages a bidirectional state-space model equipped with a gated skip connection and a learnable weighted-average pooling mechanism applied to periodically inserted learned queries. This structure enables hierarchical downsampling across both spatial and temporal dimensions, preserving performance in a cost-effective manner. Across challenging hour-long video understanding tasks, our approach demonstrates competitive results against state-of-the-art models, while significantly reducing overall token budget. Notably, replacing our state-space model with conventional modules results in substantial performance degradation, highlighting the advantages of the proposed state-space modeling for effectively compressing multi-frame video information. Our framework emphasizes resource-conscious efficiency, making it practical for real-world deployments. We validate its scalability and generality across multiple benchmarks, achieving the dual objectives of efficient resource usage and comprehensive video understanding.
[432] RealSR-R1: Reinforcement Learning for Real-World Image Super-Resolution with Vision-Language Chain-of-Thought
Junbo Qiao, Miaomiao Cai, Wei Li, Xudong Huang, Jie Hu, Xinghao Chen, Shaohui Lin, Hongkai Xiong
Main category: cs.CV
TL;DR: RealSR-R1 introduces a vision-language reasoning framework (VLCoT) with reinforcement learning (GRPO) for real-world image super-resolution, using text-guided progressive restoration with multiple reward functions.
Details
Motivation: Existing real-world image super-resolution methods struggle with accurate understanding of degraded image content, leading to low-fidelity and unnatural reconstruction results. The paper aims to empower SR models with understanding and reasoning capabilities similar to human image processing.Method: Proposes VLCoT framework integrating vision and language reasoning, inspired by Chain of Thought in LLMs. Introduces Group Relative Policy Optimization (GRPO) with four reward functions: format reward (standardizes CoT process), degradation reward (accurate degradation estimation), understanding reward (content accuracy), and generation reward (visual expert model evaluates image quality).
Result: Extensive experiments show RealSR-R1 can generate realistic details and accurately understand image content, especially in semantically rich scenes or images with severe degradation.
Conclusion: The proposed RealSR-R1 with VLCoT-GRPO framework successfully integrates vision-language reasoning with reinforcement learning to improve real-world image super-resolution, particularly for challenging degradation scenarios.
Abstract: Real-World Image Super-Resolution is one of the most challenging task in image restoration. However, existing methods struggle with an accurate understanding of degraded image content, leading to reconstructed results that are both low-fidelity and unnatural. We present RealSR-R1 in this work, which empowers the RealSR models with understanding and reasoning capabilities. Inspired by the success of Chain of Thought (CoT) in large language models (LLMs), we simulate the human process of handling degraded images and propose the VLCoT framework, which integrates vision and language reasoning. The framework aims to precisely restore image details by progressively generating more comprehensive text and higher-resolution images. To overcome the challenge of traditional supervised learning CoT failing to generalize to real-world scenarios, we introduce, for the first time, Group Relative Policy Optimization (GRPO) into the Real-World Image Super-Resolution task. We propose VLCoT-GRPO as a solution, which designs four reward functions: (1) Format reward, used to standardize the CoT process; (2) Degradation reward, to incentivize accurate degradation estimation; (3) Understanding reward, to ensure the accuracy of the generated content; and (4) Generation reward, where we propose using a visual expert model to evaluate the quality of generated images, encouraging the model to generate more realistic images. Extensive experiments demonstrate that our proposed RealSR-R1 can generate realistic details and accurately understand image content, particularly in semantically rich scenes or images with severe degradation.
[433] Modulate and Reconstruct: Learning Hyperspectral Imaging from Misaligned Smartphone Views
Daniil Reutsky, Daniil Vladimirov, Yasin Mamedov, Georgy Perevozchikov, Nancy Mehta, Egor Ershov, Radu Timofte
Main category: cs.CV
TL;DR: A multi-image hyperspectral reconstruction framework using triple-camera smartphones with spectral filters to improve reconstruction accuracy from RGB images.
Details
Motivation: Hyperspectral reconstruction from RGB images is ill-posed due to severe spectral information loss. Single RGB image approaches limit reconstruction accuracy, so the authors propose leveraging multiple images with spectral filters for richer spectral observations.Method: Proposes a multi-image-to-hyperspectral reconstruction (MI-HSR) framework using a triple-camera smartphone system with two lenses equipped with carefully selected spectral filters. Introduces Doomer dataset with aligned images from three smartphone cameras and a hyperspectral reference camera across diverse scenes.
Result: The proposed HSR model achieves consistent improvements over existing methods, allowing 30% more accurate spectral estimation compared to ordinary RGB cameras. The multi-view spectral filtering approach unlocks more accurate and practical hyperspectral imaging solutions.
Conclusion: Multi-view spectral filtering with commodity hardware can significantly improve hyperspectral reconstruction accuracy, making hyperspectral imaging more practical and accessible through smartphone-based solutions.
Abstract: Hyperspectral reconstruction (HSR) from RGB images is a fundamentally ill-posed problem due to severe spectral information loss. Existing approaches typically rely on a single RGB image, limiting reconstruction accuracy. In this work, we propose a novel multi-image-to-hyperspectral reconstruction (MI-HSR) framework that leverages a triple-camera smartphone system, where two lenses are equipped with carefully selected spectral filters. Our configuration, grounded in theoretical and empirical analysis, enables richer and more diverse spectral observations than conventional single-camera setups. To support this new paradigm, we introduce Doomer, the first dataset for MI-HSR, comprising aligned images from three smartphone cameras and a hyperspectral reference camera across diverse scenes. We show that the proposed HSR model achieves consistent improvements over existing methods on the newly proposed benchmark. In a nutshell, our setup allows 30% towards more accurately estimated spectra compared to an ordinary RGB camera. Our findings suggest that multi-view spectral filtering with commodity hardware can unlock more accurate and practical hyperspectral imaging solutions.
[434] Topological Signatures vs. Gradient Histograms: A Comparative Study for Medical Image Classification
Faisal Ahmed
Main category: cs.CV
TL;DR: Comparative evaluation of HOG and TDA features for retinal fundus image classification, showing both achieve similar performance with XGBoost as best model.
Details
Motivation: To compare two fundamentally different feature extraction paradigms (HOG and TDA) for medical image classification, specifically for retinal fundus imagery, to understand their complementary representations and potential for integration.Method: Extracted 26,244 HOG features and 800 TDA features from APTOS retinal fundus dataset, trained seven classical ML models (logistic regression, random forest, XGBoost, SVM, decision trees, k-NN, Extra Trees) using 10-fold cross-validation for binary and multi-class classification tasks.
Result: XGBoost achieved best performance: 94.29% (HOG) and 94.18% (TDA) accuracy for binary classification; 74.41% (HOG) and 74.69% (TDA) for multi-class classification, showing similar performance between feature types.
Conclusion: Gradient-based (HOG) and topological (TDA) features provide complementary representations of retinal image structure, highlighting potential for integrating both approaches for interpretable and robust medical image classification.
Abstract: This work presents a comparative evaluation of two fundamentally different feature extraction paradigms–Histogram of Oriented Gradients (HOG) and Topological Data Analysis (TDA)–for medical image classification, with a focus on retinal fundus imagery. HOG captures local structural information by modeling gradient orientation distributions within spatial regions, effectively encoding texture and edge patterns. In contrast, TDA, implemented through cubical persistent homology, extracts global topological descriptors that characterize shape, connectivity, and intensity-based structure across images. We evaluate both approaches on the publicly available APTOS retinal fundus dataset for two classification tasks: binary classification (normal vs. diabetic retinopathy (DR)) and five-class DR severity grading. From each image, 26,244 HOG features and 800 TDA features are extracted and independently used to train seven classical machine learning models, including logistic regression, random forest, XGBoost, support vector machines, decision trees, k-nearest neighbors, and Extra Trees, using 10-fold cross-validation. Experimental results show that XGBoost achieves the best performance across both feature types. For binary classification, accuracies of 94.29% (HOG) and 94.18% (TDA) are obtained, while multi-class classification yields accuracies of 74.41% and 74.69%, respectively. These results demonstrate that gradient-based and topological features provide complementary representations of retinal image structure and highlight the potential of integrating both approaches for interpretable and robust medical image classification.
[435] “PhyWorldBench”: A Comprehensive Evaluation of Physical Realism in Text-to-Video Models
Jing Gu, Xian Liu, Yu Zeng, Ashwin Nagarajan, Fangrui Zhu, Daniel Hong, Yue Fan, Qianqi Yan, Kaiwen Zhou, Ming-Yu Liu, Xin Eric Wang
Main category: cs.CV
TL;DR: PhyWorldBench is a comprehensive benchmark for evaluating video generation models’ adherence to physical laws, covering fundamental to complex physics scenarios and including an Anti-Physics category to test logical consistency.
Details
Motivation: While video generation models have achieved high-quality visual output, their ability to accurately simulate physical phenomena remains a critical unresolved challenge, necessitating systematic evaluation of physics realism.Method: Developed PhyWorldBench with 1050 curated prompts across fundamental physics, composite scenarios, and Anti-Physics categories; used both human evaluation and a novel zero-shot method leveraging multimodal LLMs for physics realism assessment.
Result: Evaluated 12 state-of-the-art text-to-video models (5 open-source, 5 proprietary) revealing significant challenges in adhering to physical laws; identified performance variations across different physical phenomena and prompt types.
Conclusion: Current video generation models struggle with physical consistency; the benchmark provides targeted recommendations for prompt engineering to enhance physics fidelity and establishes a foundation for future physics-aware video generation research.
Abstract: Video generation models have achieved remarkable progress in creating high-quality, photorealistic content. However, their ability to accurately simulate physical phenomena remains a critical and unresolved challenge. This paper presents PhyWorldBench, a comprehensive benchmark designed to evaluate video generation models based on their adherence to the laws of physics. The benchmark covers multiple levels of physical phenomena, ranging from fundamental principles such as object motion and energy conservation to more complex scenarios involving rigid body interactions and human or animal motion. Additionally, we introduce a novel Anti-Physics category, where prompts intentionally violate real-world physics, enabling the assessment of whether models can follow such instructions while maintaining logical consistency. Besides large-scale human evaluation, we also design a simple yet effective method that utilizes current multimodal large language models to evaluate physics realism in a zero-shot fashion. We evaluate 12 state-of-the-art text-to-video generation models, including five open-source and five proprietary models, with detailed comparison and analysis. Through systematic testing across 1050 curated prompts spanning fundamental, composite, and anti-physics scenarios, we identify pivotal challenges these models face in adhering to real-world physics. We further examine their performance under diverse physical phenomena and prompt types, and derive targeted recommendations for crafting prompts that enhance fidelity to physical principles.
[436] SegQuant: A Semantics-Aware and Generalizable Quantization Framework for Diffusion Models
Jiaji Zhang, Ruichao Sun, Hailiang Zhao, Jiaju Wu, Peng Chen, Hao Li, Yuying Liu, Kingsum Chow, Gang Xiong, Shuiguang Deng
Main category: cs.CV
TL;DR: SegQuant: A unified quantization framework for diffusion models that combines segment-aware graph-based quantization with dual-scale quantization for efficient deployment without retraining.
Details
Motivation: Diffusion models have exceptional generative capabilities but are computationally intensive, making deployment challenging in resource-constrained environments. Existing post-training quantization methods rely on architecture-specific heuristics that limit generalizability and hinder industrial deployment.Method: SegQuant proposes: 1) SegLinear - a segment-aware, graph-based quantization strategy that captures structural semantics and spatial heterogeneity, and 2) DualScale - a dual-scale quantization scheme that preserves polarity-asymmetric activations crucial for visual fidelity. The framework is designed to be broadly applicable beyond Transformer-based diffusion models.
Result: The method achieves strong performance while ensuring seamless compatibility with mainstream deployment tools, offering a versatile quantization solution for diffusion models.
Conclusion: SegQuant provides a unified quantization framework that enhances cross-model versatility for diffusion models, addressing the limitations of existing post-training quantization methods and enabling more efficient deployment in resource-constrained environments.
Abstract: Diffusion models have demonstrated exceptional generative capabilities but are computationally intensive, posing significant challenges for deployment in resource-constrained or latency-sensitive environments. Quantization offers an effective means to reduce model size and computational cost, with post-training quantization (PTQ) being particularly appealing due to its compatibility with pre-trained models without requiring retraining or training data. However, existing PTQ methods for diffusion models often rely on architecture-specific heuristics that limit their generalizability and hinder integration with industrial deployment pipelines. To address these limitations, we propose SegQuant, a unified quantization framework that adaptively combines complementary techniques to enhance cross-model versatility. SegQuant consists of a segment-aware, graph-based quantization strategy (SegLinear) that captures structural semantics and spatial heterogeneity, along with a dual-scale quantization scheme (DualScale) that preserves polarity-asymmetric activations, which is crucial for maintaining visual fidelity in generated outputs. SegQuant is broadly applicable beyond Transformer-based diffusion models, achieving strong performance while ensuring seamless compatibility with mainstream deployment tools.
[437] UniLiP: Adapting CLIP for Unified Multimodal Understanding, Generation and Editing
Hao Tang, Chenwei Xie, Xiaoyi Bao, Tingyu Weng, Pandeng Li, Yun Zheng, Liwei Wang
Main category: cs.CV
TL;DR: UniLIP is a unified framework that adapts CLIP for multimodal understanding, generation, and editing through a two-stage training scheme with self-distillation and dual-condition architecture.
Details
Motivation: CLIP excels at understanding but lacks reconstruction abilities needed for unified visual encoding. Previous CLIP-based unified methods fail to balance understanding and reconstruction, leading to semantic degradation or inconsistent reconstructions.Method: Two-stage training scheme with self-distillation strategy that progressively endows CLIP with high-fidelity reconstruction while preserving comprehension. Dual-condition architecture built on MetaQuery framework uses multimodal hidden states and learnable query embeddings to leverage MLLM reasoning abilities.
Result: UniLIP outperforms larger unified models like BAGEL (7B) and Uniworld-V1 (12B) with only 1B and 3B parameters, achieving SOTA performance: 0.90 on GenEval, 0.63 on WISE, and 3.94 on ImgEdit.
Conclusion: UniLIP successfully expands CLIP’s application, establishing its continuous features as optimal for understanding tasks while achieving highly competitive performance in generation and editing tasks.
Abstract: In this paper, we propose UniLIP, a unified framework that adapts CLIP for multimodal understanding, generation and editing. Although CLIP excels at understanding, it lacks reconstruction abilities required to be a unified visual encoder. However, previous CLIP-based unified methods fail to balance understanding and reconstruction, leading to semantic degradation or inconsistent reconstructions. In contrast, we introduce a novel two-stage training scheme with a self-distillation strategy that progressively endows CLIP with high-fidelity reconstruction abilities while preserving its original comprehension performance. For enhanced reasoning and consistency in generation and editing, we further develop a dual-condition architecture built upon the MetaQuery framework. Our architecture jointly utilizes multimodal hidden states for rich contextual details and learnable query embeddings to harness the powerful reasoning abilities of Multimodal Large Language Models (MLLMs). Leveraging advanced image representation and architectural design, UniLIP demonstrates superior instruction following and edit fidelity. With only 1B and 3B parameters, UniLIP can outperform larger unified models such as BAGEL (7B) and Uniworld-V1 (12B), achieving state-of-the-art performance of 0.90 on GenEval, 0.63 on WISE, and 3.94 on ImgEdit. These results demonstrate that UniLIP successfully expands the application of CLIP, establishing its continuous features to not only serve as the optimal choice for understanding tasks but also achieve highly competitive performance in generation and editing tasks. Code and models are available at https://github.com/nnnth/UniLIP.
[438] Mamba-based Spatio-Frequency Motion Perception for Video Camouflaged Object Detection
Xin Li, Keren Fu, Qijun Zhao
Main category: cs.CV
TL;DR: Vcamba is a visual camouflage Mamba model that integrates frequency and spatial features for efficient video camouflaged object detection using spatio-frequency motion perception.
Details
Motivation: Existing VCOD methods rely on spatial appearances which have limited discriminability due to high foreground-background similarity. Frequency features can compensate for appearance limitations and perceive motion through dynamic spectral energy variations, while Mamba enables efficient motion perception in frame sequences.Method: Proposes Vcamba with: 1) Frequency-domain sequential scanning (FSS) strategy to unfold spectrum based on structural evolution patterns, 2) Adaptive frequency enhancement (AFE) module using Mamba to model causal dependencies, 3) Space-based long-range motion perception (SLMP) and frequency-based long-range motion perception (FLMP) modules, 4) Space and frequency motion fusion (SFMF) module to integrate dual-domain features.
Result: Outperforms state-of-the-art methods across 6 evaluation metrics on 2 datasets with lower computation cost, confirming superiority.
Conclusion: Vcamba effectively integrates frequency and spatial features for efficient and accurate video camouflaged object detection using spatio-frequency motion perception with Mamba’s linear-time modeling capabilities.
Abstract: Existing video camouflaged object detection (VCOD) methods primarily rely on spatial appearances for motion perception. However, the high foreground-background similarity in VCOD limits the discriminability of such features (e.g. color and texture). Recent studies demonstrate that frequency features can not only compensate for appearance limitations, but also perceive motion through dynamic variations in spectral energy. Meanwhile, the emerging state space model called Mamba enables efficient motion perception in frame sequences with its linear-time long-sequence modeling capability. Motivated by this, we propose Vcamba, a visual camouflage Mamba based on spatio-frequency motion perception that integrates frequency and spatial features for efficient and accurate VCOD. Specifically, by analyzing the spatial representations of frequency components, we reveal a structural evolution pattern that emerges from the ordered superposition of components. Based on this observation, we propose a unique frequency-domain sequential scanning (FSS) strategy to unfold the spectrum. Utilizing FSS, the adaptive frequency enhancement (AFE) module employs Mamba to model the causal dependencies within sequences, enabling effective frequency learning. Furthermore, we propose a space-based long-range motion perception (SLMP) module and a frequency-based long-range motion perception (FLMP) module to model spatio-temporal and frequency-temporal sequences. Finally, the space and frequency motion fusion module (SFMF) integrates dual-domain features into unified motion representation. Experiments show that Vcamba outperforms state-of-the-art methods across 6 evaluation metrics on 2 datasets with lower computation cost, confirming its superiority. Code is available at: https://github.com/BoydeLi/Vcamba.
[439] MAMBO-G: Magnitude-Aware Mitigation for Boosted Guidance
Shangwen Zhu, Qianyu Peng, Zhilei Shu, Yuting Hu, Zhantao Yang, Han Zhang, Zhao Pu, Andy Zheng, Xinyu Cui, Jian Zhao, Ruili Feng, Fan Cheng
Main category: cs.CV
TL;DR: MAMBO-G is a training-free acceleration framework for diffusion models that dynamically optimizes guidance magnitudes to reduce computational cost, achieving up to 4x speedup while preserving quality, particularly beneficial for video generation.
Details
Motivation: Current text-to-image and text-to-video generation using Classifier-Free Guidance (CFG) requires computationally expensive sampling schedules, especially for large models. The inefficiency comes from standard CFG schedules applying disproportionately large updates in early steps that hinder convergence speed.Method: MAMBO-G modulates the guidance scale based on the update-to-prediction magnitude ratio, dynamically optimizing guidance magnitudes during sampling. This stabilizes the trajectory and enables rapid convergence without requiring additional training. The method is plug-and-play with existing diffusion pipelines.
Result: Achieves up to 3x speedup on Stable Diffusion v3.5, 4x on Lumina, and 2x acceleration on the 14B-parameter Wan2.1 video model while preserving visual fidelity. The framework is implemented in mainstream open-source diffusion frameworks.
Conclusion: MAMBO-G provides a practical, training-free solution for efficient large-scale video synthesis and image generation by dynamically optimizing guidance magnitudes, significantly reducing computational costs while maintaining quality.
Abstract: High-fidelity text-to-image and text-to-video generation typically relies on Classifier-Free Guidance (CFG), but achieving optimal results often demands computationally expensive sampling schedules. In this work, we propose MAMBO-G, a training-free acceleration framework that significantly reduces computational cost by dynamically optimizing guidance magnitudes. We observe that standard CFG schedules are inefficient, applying disproportionately large updates in early steps that hinder convergence speed. MAMBO-G mitigates this by modulating the guidance scale based on the update-to-prediction magnitude ratio, effectively stabilizing the trajectory and enabling rapid convergence. This efficiency is particularly vital for resource-intensive tasks like video generation. Our method serves as a universal plug-and-play accelerator, achieving up to 3x speedup on Stable Diffusion v3.5 (SD3.5) and 4x on Lumina. Most notably, MAMBO-G accelerates the 14B-parameter Wan2.1 video model by 2x while preserving visual fidelity, offering a practical solution for efficient large-scale video synthesis. Our implementation follows a mainstream open-source diffusion framework and is plug-and-play with existing pipelines.
[440] WeTok: Powerful Discrete Tokenization for High-Fidelity Visual Reconstruction
Shaobin Zhuang, Yiwei Guo, Canmiao Fu, Zhipeng Huang, Zeyue Tian, Xiaohui Li, Fangyikang Wang, Ying Zhang, Chen Li, Yali Wang
Main category: cs.CV
TL;DR: WeTok is a novel visual tokenizer with group-wise lookup-free quantization and generative decoder that achieves state-of-the-art reconstruction fidelity at high compression ratios for vision generation.
Details
Motivation: Existing visual tokenizers face unsatisfactory trade-offs between compression ratios and reconstruction fidelity, limiting their effectiveness in vision generation tasks.Method: Two core innovations: (1) Group-wise lookup-free Quantization (GQ) partitions latent features into groups for efficient quantization, overcoming memory/computation limitations; (2) Generative Decoder (GD) with prior noise variable probabilistically models visual data distribution conditioned on discrete tokens.
Result: Achieves record-low zero-shot rFID of 0.12 at high-fidelity setting (400% compression ratio), outperforming FLUX-VAE (0.18) and SD-VAE 3.5 (0.19). At high compression (768× ratio), achieves rFID 3.49, substantially better than Cosmos (4.57 at only 50% compression ratio).
Conclusion: WeTok tokenizer provides superior trade-off between compression and reconstruction fidelity, enabling better visual generation through efficient quantization and probabilistic modeling.
Abstract: Visual tokenizer is a critical component for vision generation. However, the existing tokenizers often face unsatisfactory trade-off between compression ratios and reconstruction fidelity. To fill this gap, we introduce a powerful and concise WeTok tokenizer, which surpasses the previous leading tokenizers via two core innovations. (1) Group-wise lookup-free Quantization (GQ). We partition the latent features into groups, and perform lookup-free quantization for each group. As a result, GQ can efficiently overcome memory and computation limitations of prior tokenizers, while achieving a reconstruction breakthrough with more scalable codebooks. (2) Generative Decoder (GD). Different from prior tokenizers, we introduce a generative decoder with a prior of extra noise variable. In this case, GD can probabilistically model the distribution of visual data conditioned on discrete tokens, allowing WeTok to reconstruct visual details, especially at high compression ratio. On the ImageNet 50k validation set, at a high-fidelity setting, WeTok achieves a record-low zero-shot rFID of 0.12, outperforming leading continuous tokenizers like FLUX-VAE (0.18) and SD-VAE 3.5 (0.19) with 400% compression ratio. Furthermore, in a high-compression regime, WeTok achieves a zero-shot rFID of 3.49 at a 768$\times$ compression ratio, substantially surpassing Cosmos, which scores 4.57 at only 50% our compression ratio. Code and models are available: https://github.com/zhuangshaobin/WeTok.
[441] Robust Image Stitching with Optimal Plane
Lang Nie, Yuan Mei, Kang Liao, Yunqiu Xu, Chunyu Lin, Bin Xiao
Main category: cs.CV
TL;DR: RopStitch is an unsupervised deep image stitching framework that achieves robust and natural image stitching through a dual-branch architecture for content perception and virtual optimal planes for alignment-preservation balance.
Details
Motivation: Traditional image stitching methods struggle with robustness across diverse real-world scenes and face the contradiction between content alignment and structural preservation. There's a need for an unsupervised approach that can handle various scenes while maintaining natural-looking results.Method: 1) Dual-branch architecture: pretrained branch for semantically invariant representations + learnable branch for fine-grained discriminative features, merged via controllable correlation factor. 2) Virtual optimal planes: models homography decomposition coefficients estimation with iterative coefficient predictor and minimal semantic distortion constraint to find optimal alignment plane. 3) Bidirectional warping of both views onto the optimal plane.
Result: Extensive experiments across various datasets show RopStitch significantly outperforms existing methods, particularly in scene robustness and content naturalness.
Conclusion: RopStitch provides an effective unsupervised solution for image stitching that balances robustness and naturalness through innovative dual-branch feature integration and optimal plane estimation techniques.
Abstract: We present \textit{RopStitch}, an unsupervised deep image stitching framework with both robustness and naturalness. To ensure the robustness of \textit{RopStitch}, we propose to incorporate the universal prior of content perception into the image stitching model by a dual-branch architecture. It separately captures coarse and fine features and integrates them to achieve highly generalizable performance across diverse unseen real-world scenes. Concretely, the dual-branch model consists of a pretrained branch to capture semantically invariant representations and a learnable branch to extract fine-grained discriminative features, which are then merged into a whole by a controllable factor at the correlation level. Besides, considering that content alignment and structural preservation are often contradictory to each other, we propose a concept of virtual optimal planes to relieve this conflict. To this end, we model this problem as a process of estimating homography decomposition coefficients, and design an iterative coefficient predictor and minimal semantic distortion constraint to identify the optimal plane. This scheme is finally incorporated into \textit{RopStitch} by warping both views onto the optimal plane bidirectionally. Extensive experiments across various datasets demonstrate that \textit{RopStitch} significantly outperforms existing methods, particularly in scene robustness and content naturalness. The code is available at {\color{red}https://github.com/MmelodYy/RopStitch}.
[442] Hyperspectral Imaging
Danfeng Hong, Chenyu Li, Naoto Yokoya, Bing Zhang, Xiuping Jia, Antonio Plaza, Paolo Gamba, Jon Atli Benediktsson, Jocelyn Chanussot
Main category: cs.CV
TL;DR: A comprehensive primer on hyperspectral imaging covering fundamentals, analysis methods, applications, challenges, and future directions including AI-driven techniques.
Details
Motivation: To provide a comprehensive overview of hyperspectral imaging as an advanced sensing modality that captures spatial and spectral information for non-invasive analysis across multiple domains.Method: The paper presents a primer covering physical principles, sensor architectures, data acquisition, calibration, classical and modern analysis methods including dimensionality reduction, classification, spectral unmixing, and AI-driven deep learning techniques.
Result: A comprehensive resource summarizing HSI fundamentals, applications across Earth observation, agriculture, biomedicine, industrial inspection, cultural heritage, and security, along with analysis methods and emerging solutions.
Conclusion: HSI is evolving into a general-purpose cross-disciplinary platform with transformative potential, driven by sensor miniaturization, self-supervised learning, and foundation models for scalable, real-time systems.
Abstract: Hyperspectral imaging (HSI) is an advanced sensing modality that simultaneously captures spatial and spectral information, enabling non-invasive, label-free analysis of material, chemical, and biological properties. This Primer presents a comprehensive overview of HSI, from the underlying physical principles and sensor architectures to key steps in data acquisition, calibration, and correction. We summarize common data structures and highlight classical and modern analysis methods, including dimensionality reduction, classification, spectral unmixing, and AI-driven techniques such as deep learning. Representative applications across Earth observation, precision agriculture, biomedicine, industrial inspection, cultural heritage, and security are also discussed, emphasizing HSI’s ability to uncover sub-visual features for advanced monitoring, diagnostics, and decision-making. Persistent challenges, such as hardware trade-offs, acquisition variability, and the complexity of high-dimensional data, are examined alongside emerging solutions, including computational imaging, physics-informed modeling, cross-modal fusion, and self-supervised learning. Best practices for dataset sharing, reproducibility, and metadata documentation are further highlighted to support transparency and reuse. Looking ahead, we explore future directions toward scalable, real-time, and embedded HSI systems, driven by sensor miniaturization, self-supervised learning, and foundation models. As HSI evolves into a general-purpose, cross-disciplinary platform, it holds promise for transformative applications in science, technology, and society.
[443] You Only Pose Once: A Minimalist’s Detection Transformer for Monocular RGB Category-level 9D Multi-Object Pose Estimation
Hakjin Lee, Junghoon Seo, Jaehoon Sim
Main category: cs.CV
TL;DR: YOPO: A single-stage, query-based framework that unifies object detection and 9-DoF pose estimation using only RGB images, achieving state-of-the-art performance on category-level pose estimation benchmarks.
Details
Motivation: Current methods for 9-DoF pose estimation rely on pseudo-depth, CAD models, or multi-stage pipelines. The authors aim to create a simpler, RGB-only alternative that learns directly at the category level and unifies detection with pose estimation.Method: YOPO extends a transformer detector with a lightweight pose head, bounding-box-conditioned translation module, and 6D-aware Hungarian matching cost. It’s trained end-to-end with only RGB images and category-level pose labels.
Result: Achieves 79.6% IoU50 and 54.1% under the 10°10cm metric on REAL275 dataset, surpassing prior RGB-only methods and closing much of the gap to RGB-D systems. Sets new state-of-the-art on three benchmarks.
Conclusion: YOPO demonstrates that object detection and 9-DoF pose estimation can be unified with high performance using only RGB images, providing a simpler alternative to existing multi-stage or depth-dependent methods.
Abstract: Accurately recovering the full 9-DoF pose of unseen instances within specific categories from a single RGB image remains a core challenge for robotics and automation. Most existing solutions still rely on pseudo-depth, CAD models, or multi-stage cascades that separate 2D detection from pose estimation. Motivated by the need for a simpler, RGB-only alternative that learns directly at the category level, we revisit a longstanding question: Can object detection and 9-DoF pose estimation be unified with high performance, without any additional data? We show that they can with our method, YOPO, a single-stage, query-based framework that treats category-level 9-DoF estimation as a natural extension of 2D detection. YOPO augments a transformer detector with a lightweight pose head, a bounding-box-conditioned translation module, and a 6D-aware Hungarian matching cost. The model is trained end-to-end only with RGB images and category-level pose labels. Despite its minimalist design, YOPO sets a new state of the art on three benchmarks. On the REAL275 dataset, it achieves 79.6% $\rm{IoU}_{50}$ and 54.1% under the $10^\circ$$10{\rm{cm}}$ metric, surpassing prior RGB-only methods and closing much of the gap to RGB-D systems. The code, models, and additional qualitative results can be found on https://mikigom.github.io/YOPO-project-page.
[444] SpecPrune-VLA: Accelerating Vision-Language-Action Models via Action-Aware Self-Speculative Pruning
Hanzhen Wang, Jiaming Xu, Yushun Xiang, Jiayi Pan, Yongkang Zhou, Yong-Lu Li, Guohao Dai
Main category: cs.CV
TL;DR: SpecPrune-VLA: A training-free two-level pruning method for Vision-Language-Action models that leverages spatial-temporal consistency and global context to accelerate inference with minimal performance degradation.
Details
Motivation: Existing VLA model acceleration methods focus only on local information from current action steps, ignoring global context, which leads to significant performance drops (>20% success rate) and limited speedup. The authors identify spatial-temporal consistency in VLA tasks where consecutive input images exhibit high similarity.Method: Proposes SpecPrune-VLA with three components: (1) Action-level static pruning using global history and local attention to reduce visual tokens per action, (2) Layer-level dynamic pruning that adaptively prunes tokens based on layer-wise importance, (3) Lightweight action-aware controller that classifies actions as coarse- or fine-grained based on end effector speed and adjusts pruning aggressiveness accordingly.
Result: Achieves up to 1.57× speedup in LIBERO simulation and 1.70× on real-world tasks with negligible success rate degradation, significantly outperforming existing methods that cause >20% success rate drops.
Conclusion: The paper demonstrates that combining local information with global context for token selection enables effective pruning of VLA models while maintaining performance, addressing the spatial-temporal consistency in VLA tasks.
Abstract: Pruning is a typical acceleration technique for compute-bound models by removing computation on unimportant values. Recently, it has been applied to accelerate Vision-Language-Action (VLA) model inference. However, existing acceleration methods focus on local information from the current action step and ignore the global context, leading to >20% success rate drop and limited speedup in some scenarios. In this paper, we point out spatial-temporal consistency in VLA tasks: input images in consecutive steps exhibit high similarity, and propose the key insight that token selection should combine local information with global context of the model. Based on this, we propose SpecPrune-VLA, a training-free, two-level pruning method with heuristic control. (1) Action-level static pruning. We leverage global history and local attention to statically reduce visual tokens per action. (2) Layer-level dynamic pruning. We prune tokens adaptively per layer based on layer-wise importance. (3) Lightweight action-aware controller: We classify actions as coarse- or fine-grained by the speed of the end effector and adjust pruning aggressiveness accordingly. Extensive experiments show that SpecPrune-VLA achieves up to 1.57$\times$ speedup in LIBERO simulation and 1.70$\times$ on real-world tasks, with negligible success rate degradation.
[445] HyPlaneHead: Rethinking Tri-plane-like Representations in Full-Head Image Synthesis
Heyuan Li, Kenkun Liu, Lingteng Qiu, Qi Zuo, Keru Zheng, Zilong Dong, Xiaoguang Han
Main category: cs.CV
TL;DR: HyPlaneHead introduces a hybrid-plane representation combining planar and spherical planes with near-equal-area warping to address feature entanglement and penetration issues in 3D-aware GANs for head synthesis.
Details
Motivation: Tri-plane representations in 3D-aware GANs suffer from feature entanglement causing mirroring artifacts, while spherical tri-planes have uneven mapping and inefficient feature utilization. Both methods also experience feature penetration across channels.Method: Proposes hybrid-plane representation combining planar and spherical planes, introduces near-equal-area warping for spherical planes to maximize feature map utilization, and synthesizes single-channel unified feature maps to eliminate feature penetration.
Result: Achieves state-of-the-art performance in full-head image synthesis, addressing previous limitations of tri-plane and spherical tri-plane representations.
Conclusion: HyPlaneHead’s hybrid representation with technical improvements enables superior 3D-aware head synthesis by systematically addressing fundamental issues in existing tri-plane methods.
Abstract: Tri-plane-like representations have been widely adopted in 3D-aware GANs for head image synthesis and other 3D object/scene modeling tasks due to their efficiency. However, querying features via Cartesian coordinate projection often leads to feature entanglement, which results in mirroring artifacts. A recent work, SphereHead, attempted to address this issue by introducing spherical tri-planes based on a spherical coordinate system. While it successfully mitigates feature entanglement, SphereHead suffers from uneven mapping between the square feature maps and the spherical planes, leading to inefficient feature map utilization during rendering and difficulties in generating fine image details. Moreover, both tri-plane and spherical tri-plane representations share a subtle yet persistent issue: feature penetration across convolutional channels can cause interference between planes, particularly when one plane dominates the others. These challenges collectively prevent tri-plane-based methods from reaching their full potential. In this paper, we systematically analyze these problems for the first time and propose innovative solutions to address them. Specifically, we introduce a novel hybrid-plane (hy-plane for short) representation that combines the strengths of both planar and spherical planes while avoiding their respective drawbacks. We further enhance the spherical plane by replacing the conventional theta-phi warping with a novel near-equal-area warping strategy, which maximizes the effective utilization of the square feature map. In addition, our generator synthesizes a single-channel unified feature map instead of multiple feature maps in separate channels, thereby effectively eliminating feature penetration. With a series of technical improvements, our hy-plane representation enables our method, HyPlaneHead, to achieve state-of-the-art performance in full-head image synthesis.
[446] Reading Images Like Texts: Sequential Image Understanding in Vision-Language Models
Yueyan Li, Chenggong Zhao, Zeyuan Zang, Caixia Yuan, Xiaojie Wang
Main category: cs.CV
TL;DR: This paper analyzes Vision-Language Models (VLMs) by deconstructing visual processing into object recognition and spatial perception pathways, inspired by human vision’s dual-stream hypothesis, and proposes efficiency improvements.
Details
Motivation: Existing VLMs process images serially, which diverges from human parallel vision, and their opaque internal mechanisms hinder understanding and architectural innovation. The authors aim to provide deeper insights into VLM internals.Method: The study deconstructs VLM visual processing into object recognition (analyzed via text token maps revealing two-stage perception) and spatial perception (theoretically deriving geometric structure of positional representations). Based on findings, they propose a token compression algorithm using a plug-and-play visual decoder and RoPE scaling technique.
Result: The analysis reveals that object recognition unfolds as a two-stage process from shallow to deep layers, and identifies the geometric structure underlying positional representations. The proposed methods improve decoding efficiency and enhance spatial reasoning.
Conclusion: The work provides deeper understanding of VLM internals and offers clear principles for designing more capable future architectures, bridging the gap between serial VLM processing and parallel human vision.
Abstract: Vision-Language Models (VLMs) have demonstrated remarkable performance across a variety of real-world tasks. However, existing VLMs typically process visual information by serializing images, a method that diverges significantly from the parallel nature of human vision. Moreover, their opaque internal mechanisms hinder both deeper understanding and architectural innovation. Inspired by the dual-stream hypothesis of human vision, which distinguishes the “what” and “where” pathways, we deconstruct the visual processing in VLMs into object recognition and spatial perception for separate study. For object recognition, we convert images into text token maps and find that the model’s perception of image content unfolds as a two-stage process from shallow to deep layers, beginning with attribute recognition and culminating in semantic disambiguation. For spatial perception, we theoretically derive and empirically verify the geometric structure underlying the positional representation in VLMs. Based on these findings, we introduce an instruction-agnostic token compression algorithm based on a plug-and-play visual decoder to improve decoding efficiency, and a RoPE scaling technique to enhance spatial reasoning. Through rigorous experiments, our work validates these analyses, offering a deeper understanding of VLM internals and providing clear principles for designing more capable future architectures.
[447] MedVSR: Medical Video Super-Resolution with Cross State-Space Propagation
Xinyu Liu, Guolei Sun, Cheng Wang, Yixuan Yuan, Ender Konukoglu
Main category: cs.CV
TL;DR: MedVSR: A medical video super-resolution framework using Cross State-Space Propagation for alignment and Inner State-Space Reconstruction for artifact reduction in medical videos.
Details
Motivation: High-resolution medical videos are crucial for accurate diagnosis but hard to acquire due to hardware limitations. Low-resolution medical videos present unique challenges including camera shake, noise, abrupt frame transitions causing optical flow errors, and current VSR models introduce artifacts that can mislead doctors.Method: Proposes MedVSR with two key components: 1) Cross State-Space Propagation (CSSP) projects distant frames as control matrices within state-space models to selectively propagate consistent features for alignment, 2) Inner State-Space Reconstruction (ISSR) enhances tissue structures and reduces artifacts through joint long-range spatial feature learning and large-kernel short-range information aggregation.
Result: Experiments across four datasets in diverse medical scenarios (endoscopy and cataract surgeries) show MedVSR significantly outperforms existing VSR models in both reconstruction performance and efficiency.
Conclusion: MedVSR provides an effective solution for medical video super-resolution, addressing unique challenges in medical imaging through state-space modeling for alignment and reconstruction, with potential to improve diagnostic accuracy.
Abstract: High-resolution (HR) medical videos are vital for accurate diagnosis, yet are hard to acquire due to hardware limitations and physiological constraints. Clinically, the collected low-resolution (LR) medical videos present unique challenges for video super-resolution (VSR) models, including camera shake, noise, and abrupt frame transitions, which result in significant optical flow errors and alignment difficulties. Additionally, tissues and organs exhibit continuous and nuanced structures, but current VSR models are prone to introducing artifacts and distorted features that can mislead doctors. To this end, we propose MedVSR, a tailored framework for medical VSR. It first employs Cross State-Space Propagation (CSSP) to address the imprecise alignment by projecting distant frames as control matrices within state-space models, enabling the selective propagation of consistent and informative features to neighboring frames for effective alignment. Moreover, we design an Inner State-Space Reconstruction (ISSR) module that enhances tissue structures and reduces artifacts with joint long-range spatial feature learning and large-kernel short-range information aggregation. Experiments across four datasets in diverse medical scenarios, including endoscopy and cataract surgeries, show that MedVSR significantly outperforms existing VSR models in reconstruction performance and efficiency. Code released at https://github.com/CUHK-AIM-Group/MedVSR.
[448] Residual Vector Quantization For Communication-Efficient Multi-Agent Perception
Dereje Shenkut, B. V. K Vijaya Kumar
Main category: cs.CV
TL;DR: ReVQom is a learned feature compression method for multi-agent collaborative perception that uses residual vector quantization to dramatically reduce communication bandwidth while preserving spatial identity and accuracy.
Details
Motivation: Multi-agent collaborative perception improves scene understanding but faces scalability challenges due to communication bandwidth constraints. Current methods transmit large feature maps, limiting practical deployment in V2X (vehicle-to-everything) systems.Method: End-to-end learned feature codec with bottleneck network for dimension reduction followed by multi-stage residual vector quantization (RVQ). Only per-pixel code indices are transmitted instead of full feature vectors, achieving 6-30 bits per pixel compression.
Result: Achieves 273x compression at 30 bpp to 1365x compression at 6 bpp on DAIR-V2X dataset. At 18 bpp (455x compression), matches or outperforms raw-feature collaborative perception. Enables ultra-low-bandwidth operation with graceful degradation at 6-12 bpp.
Conclusion: ReVQom enables efficient and accurate multi-agent collaborative perception with dramatic bandwidth reduction, taking a step toward practical V2X deployment while preserving spatial identity and minimizing accuracy loss.
Abstract: Multi-agent collaborative perception (CP) improves scene understanding by sharing information across connected agents such as autonomous vehicles, unmanned aerial vehicles, and robots. Communication bandwidth, however, constrains scalability. We present ReVQom, a learned feature codec that preserves spatial identity while compressing intermediate features. ReVQom is an end-to-end method that compresses feature dimensions via a simple bottleneck network followed by multi-stage residual vector quantization (RVQ). This allows only per-pixel code indices to be transmitted, reducing payloads from 8192 bits per pixel (bpp) of uncompressed 32-bit float features to 6-30 bpp per agent with minimal accuracy loss. On DAIR-V2X real-world CP dataset, ReVQom achieves 273x compression at 30 bpp to 1365x compression at 6 bpp. At 18 bpp (455x), ReVQom matches or outperforms raw-feature CP, and at 6-12 bpp it enables ultra-low-bandwidth operation with graceful degradation. ReVQom allows efficient and accurate multi-agent collaborative perception with a step toward practical V2X deployment.
[449] Vid-LLM: A Compact Video-based 3D Multimodal LLM with Reconstruction-Reasoning Synergy
Haijier Chen, Bo Xu, Shoujian Zhang, Haoze Liu, Jiaxuan Lin, Jingrong Wang
Main category: cs.CV
TL;DR: Vid-LLM is a video-based 3D multimodal LLM that processes video inputs without requiring external 3D data, using geometric priors and a Cross-Task Adapter to align 3D geometry with vision-language representations for 3D scene understanding tasks.
Details
Motivation: Existing 3D-MLLMs depend on 3D data inputs, limiting scalability and generalization. The authors aim to develop a practical 3D-MLLM that can work directly from video inputs without external 3D data for real-world deployment.Method: Proposes Vid-LLM with: 1) Cross-Task Adapter (CTA) module to align 3D geometric priors with vision-language representations, 2) Metric Depth Model to recover real-scale geometry, and 3) two-stage distillation optimization for stable training and fast convergence.
Result: Extensive experiments show effectiveness on 3D Question Answering, 3D Dense Captioning, and 3D Visual Grounding tasks, demonstrating superior multi-task capabilities compared to existing methods.
Conclusion: Vid-LLM provides a practical solution for 3D scene understanding by processing video inputs directly without external 3D data, achieving strong performance across multiple 3D reasoning tasks through effective geometric prior integration.
Abstract: Recent developments in Multimodal Large Language Models (MLLMs) have significantly improved Vision-Language (VL) reasoning in 2D domains. However, extending these capabilities to 3D scene understanding remains a major challenge. Existing 3D Multimodal Large Language Models (3D-MLLMs) often depend on 3D data inputs, which limits scalability and generalization. To address this limitation, we propose Vid-LLM, a video-based 3D-MLLM that directly processes video inputs without requiring external 3D data, making it practical for real-world deployment. In our method, the geometric prior are directly used to improve the performance of the sceen perception. To integrate the geometric cues into the MLLM compactly, we design a Cross-Task Adapter (CTA) module to align the 3D geometric priors with the vision-language representations. To ensure geometric consistency and integrity, we introduce a Metric Depth Model that recovers real-scale geometry from the reconstruction outputs. Finally, the model is fine-tuned with a two-stage distillation optimization strategy, realizing fast convergence and stabilizes training. Extensive experiments across diverse benchmarks verified the effectiveness of our method on 3D Question Answering, 3D Dense Captioning and 3D Visual Grounding tasks, demonstrating the superior multi-task capabilities.
[450] PAL-Net: A Point-Wise CNN with Patch-Attention for 3D Facial Landmark Localization
Ali Shadman Yazdi, Annalisa Cappella, Benedetta Baldini, Riccardo Solazzo, Gianluca Tartaglia, Chiarella Sforza, Giuseppe Baselli
Main category: cs.CV
TL;DR: PAL-Net: A deep learning pipeline for automatic localization of 50 anatomical landmarks on 3D facial scans using patch-based pointwise CNN with attention mechanisms
Details
Motivation: Manual annotation of anatomical landmarks on 3D facial scans is time-consuming and expertise-dependent, yet critical for clinical assessments and research. Existing deep learning methods often focus on pseudo-landmarks or require complex inputs, limiting clinical applicability.Method: Combines coarse alignment, region-of-interest filtering, initial landmark approximation, and a patch-based pointwise CNN enhanced by attention mechanisms for localizing 50 anatomical landmarks on stereo-photogrammetry facial models.
Result: Achieved mean localization error of 3.686 mm on 214 annotated scans, preserving anatomical distances with 2.822 mm average error (comparable to intra-observer variability). On FaceScape dataset (700 subjects): 0.41 mm point-wise error and 0.38 mm distance-wise error.
Conclusion: PAL-Net offers favorable accuracy-computation trade-off, generalizes effectively across datasets and facial regions, provides lightweight scalable solution for high-throughput 3D anthropometric analysis, with potential to support clinical workflows and reduce manual annotation reliance.
Abstract: Manual annotation of anatomical landmarks on 3D facial scans is a time-consuming and expertise-dependent task, yet it remains critical for clinical assessments, morphometric analysis, and craniofacial research. While several deep learning methods have been proposed for facial landmark localization, most focus on pseudo-landmarks or require complex input representations, limiting their clinical applicability. This study presents a fully automated deep learning pipeline (PAL-Net) for localizing 50 anatomical landmarks on stereo-photogrammetry facial models. The method combines coarse alignment, region-of-interest filtering, and an initial approximation of landmarks with a patch-based pointwise CNN enhanced by attention mechanisms. Trained and evaluated on 214 annotated scans from healthy adults, PAL-Net achieved a mean localization error of 3.686 mm and preserves relevant anatomical distances with a 2.822 mm average error, comparable to intra-observer variability. To assess generalization, the model was further evaluated on 700 subjects from the FaceScape dataset, achieving a point-wise error of 0.41,mm and a distance-wise error of 0.38,mm. Compared to existing methods, PAL-Net offers a favorable trade-off between accuracy and computational cost. While performance degrades in regions with poor mesh quality (e.g., ears, hairline), the method demonstrates consistent accuracy across most anatomical regions. PAL-Net generalizes effectively across datasets and facial regions, outperforming existing methods in both point-wise and structural evaluations. It provides a lightweight, scalable solution for high-throughput 3D anthropometric analysis, with potential to support clinical workflows and reduce reliance on manual annotation. Source code can be found at https://github.com/Ali5hadman/PAL-Net-A-Point-Wise-CNN-with-Patch-Attention
[451] RAP: 3D Rasterization Augmented End-to-End Planning
Lan Feng, Yang Gao, Eloi Zablocki, Quanyi Li, Wuyang Li, Sichao Liu, Matthieu Cord, Alexandre Alahi
Main category: cs.CV
TL;DR: RAP uses lightweight 3D rasterization instead of photorealistic rendering for end-to-end driving training, enabling scalable data augmentation with semantic fidelity and sim-to-real feature alignment.
Details
Motivation: Imitation learning for end-to-end driving lacks recovery data in closed-loop deployment, causing small mistakes to compound. Photorealistic rendering solutions are too slow and costly for training. The authors argue photorealism is unnecessary - semantic fidelity and scalability matter more for driving tasks.Method: Proposes 3D Rasterization: lightweight rasterization of annotated primitives instead of costly rendering, enabling augmentations like counterfactual recovery maneuvers and cross-agent view synthesis. Introduces Raster-to-Real feature-space alignment to bridge sim-to-real gap. Together forms RAP pipeline.
Result: Achieves state-of-the-art closed-loop robustness and long-tail generalization, ranking first on four major benchmarks: NAVSIM v1/v2, Waymo Open Dataset Vision-based E2E Driving, and Bench2Drive.
Conclusion: Lightweight rasterization with feature alignment suffices to scale E2E training, offering a practical alternative to photorealistic rendering for autonomous driving planning.
Abstract: Imitation learning for end-to-end driving trains policies only on expert demonstrations. Once deployed in a closed loop, such policies lack recovery data: small mistakes cannot be corrected and quickly compound into failures. A promising direction is to generate alternative viewpoints and trajectories beyond the logged path. Prior work explores photorealistic digital twins via neural rendering or game engines, but these methods are prohibitively slow and costly, and thus mainly used for evaluation. In this work, we argue that photorealism is unnecessary for training end-to-end planners. What matters is semantic fidelity and scalability: driving depends on geometry and dynamics, not textures or lighting. Motivated by this, we propose 3D Rasterization, which replaces costly rendering with lightweight rasterization of annotated primitives, enabling augmentations such as counterfactual recovery maneuvers and cross-agent view synthesis. To transfer these synthetic views effectively to real-world deployment, we introduce a Raster-to-Real feature-space alignment that bridges the sim-to-real gap. Together, these components form Rasterization Augmented Planning (RAP), a scalable data augmentation pipeline for planning. RAP achieves state-of-the-art closed-loop robustness and long-tail generalization, ranking first on four major benchmarks: NAVSIM v1/v2, Waymo Open Dataset Vision-based E2E Driving, and Bench2Drive. Our results show that lightweight rasterization with feature alignment suffices to scale E2E training, offering a practical alternative to photorealistic rendering. Project page: https://alan-lanfeng.github.io/RAP/.
[452] Through the Perspective of LiDAR: A Feature-Enriched and Uncertainty-Aware Annotation Pipeline for Terrestrial Point Cloud Segmentation
Fei Zhang, Rob Chancia, Josie Clapp, Amirhossein Hassanzadeh, Dimah Dera, Richard MacKenzie, Jan van Aardt
Main category: cs.CV
TL;DR: Semi-automated uncertainty-aware pipeline for TLS point cloud segmentation reduces labeling effort through spherical projection, feature enrichment, ensemble learning, and targeted annotation, applied to create Mangrove3D dataset.
Details
Motivation: Manual annotation of terrestrial laser scanning (TLS) point clouds is costly, limiting semantic segmentation for applications like ecological monitoring. Need efficient methods to reduce labeling effort while maintaining accuracy.Method: Pipeline projects 3D points to 2D spherical grid, enriches pixels with multi-source features, trains ensemble of segmentation networks to produce pseudo-labels and uncertainty maps, uses uncertainty to guide annotation of ambiguous regions, then back-projects to 3D with three-tier visualization suite.
Result: Performance saturates after ~12 annotated scans, geometric features contribute most, compact nine-channel stacks capture nearly all discriminative power with mIoU plateauing around 0.76. Pipeline generalizes to other datasets (ForestSemantic, Semantic3D).
Conclusion: Proposed pipeline enables scalable, high-quality segmentation of TLS point clouds with reduced labeling effort, provides empirical guidance on data efficiency and feature importance, and contributes Mangrove3D dataset for ecological monitoring applications.
Abstract: Accurate semantic segmentation of terrestrial laser scanning (TLS) point clouds is limited by costly manual annotation. We propose a semi-automated, uncertainty-aware pipeline that integrates spherical projection, feature enrichment, ensemble learning, and targeted annotation to reduce labeling effort, while sustaining high accuracy. Our approach projects 3D points to a 2D spherical grid, enriches pixels with multi-source features, and trains an ensemble of segmentation networks to produce pseudo-labels and uncertainty maps, the latter guiding annotation of ambiguous regions. The 2D outputs are back-projected to 3D, yielding densely annotated point clouds supported by a three-tier visualization suite (2D feature maps, 3D colorized point clouds, and compact virtual spheres) for rapid triage and reviewer guidance. Using this pipeline, we build Mangrove3D, a semantic segmentation TLS dataset for mangrove forests. We further evaluate data efficiency and feature importance to address two key questions: (1) how much annotated data are needed and (2) which features matter most. Results show that performance saturates after ~12 annotated scans, geometric features contribute the most, and compact nine-channel stacks capture nearly all discriminative power, with the mean Intersection over Union (mIoU) plateauing at around 0.76. Finally, we confirm the generalization of our feature-enrichment strategy through cross-dataset tests on ForestSemantic and Semantic3D. Our contributions include: (i) a robust, uncertainty-aware TLS annotation pipeline with visualization tools; (ii) the Mangrove3D dataset; and (iii) empirical guidance on data efficiency and feature importance, thus enabling scalable, high-quality segmentation of TLS point clouds for ecological monitoring and beyond. The dataset and processing scripts are publicly available at https://fz-rit.github.io/through-the-lidars-eye/.
[453] MARC: Memory-Augmented RL Token Compression for Efficient Video Understanding
Peiran Wu, Zhuorui Yu, Yunze Liu, Chi-Hao Wu, Enmin Zhou, Junxiao Shen
Main category: cs.CV
TL;DR: MARC is a memory-augmented reinforcement learning method for compressing visual tokens in video understanding models, achieving 95% token reduction while maintaining near-baseline accuracy.
Details
Motivation: Visual language models face heavy computational costs when processing videos due to high frame rates and long durations. Existing token compression methods cause information loss and performance degradation, creating a need for efficient video understanding in resource-constrained settings.Method: Proposes Memory-Augmented Reinforcement Learning-based Token Compression (MARC) with a retrieve-then-compress strategy: 1) Visual Memory Retriever (VMR) selects key clips, 2) Compression Group Relative Policy Optimization (C-GRPO) distills reasoning ability from teacher to student model using reinforcement learning.
Result: Achieves near-baseline accuracy using only one frame’s tokens, reducing visual tokens by 95%, GPU memory by 72%, and latency by 23.9% across six video benchmarks.
Conclusion: MARC demonstrates potential for efficient, real-time video understanding in resource-constrained applications like video QA, surveillance, and autonomous driving through effective token compression.
Abstract: The rapid progress of large language models (LLMs) has laid the foundation for multimodal models. However, visual language models (VLMs) still face heavy computational costs when extended from images to videos due to high frame rates and long durations. Token compression is a promising solution, yet most existing training-free methods cause information loss and performance degradation. To overcome this, we propose \textbf{Memory-Augmented Reinforcement Learning-based Token Compression (MARC)}, which integrates structured retrieval and RL-based distillation. MARC adopts a \textit{retrieve-then-compress} strategy using a \textbf{Visual Memory Retriever (VMR)} to select key clips and a \textbf{Compression Group Relative Policy Optimization (C-GRPO)} framework to distil reasoning ability from a teacher to a student model. Experiments on six video benchmarks show that MARC achieves near-baseline accuracy using only one frame’s tokens – reducing visual tokens by \textbf{95%}, GPU memory by \textbf{72%}, and latency by \textbf{23.9%}. This demonstrates its potential for efficient, real-time video understanding in resource-constrained settings such as video QA, surveillance, and autonomous driving.
[454] A Multi-Strategy Framework for Enhancing Shatian Pomelo Detection in Real-World Orchards
Pan Wang, Yihao Hu, Xiaodong Bai, Jingchu Yang, Leyi Zhou, Aiping Yang, Xiangxiang Li, Meiping Ding, Jianguo Yao
Main category: cs.CV
TL;DR: REAS-Det is a novel object detection framework for Shatian pomelo detection in orchards, featuring specialized modules to handle real-world challenges like lighting variations, scale changes, and occlusion.
Details
Motivation: Existing pomelo detection models degrade in real orchard environments due to device-dependent tone shifts, illumination changes, large scale variation, and frequent occlusion, necessitating more robust solutions.Method: Proposes REAS-Det with Global-Selective Visibility Convolution (GSV-Conv) to expand visible feature space under global semantic guidance, plus C3RFEM, MultiSEAM, and Soft-NMS modules for refined separation and localization. Uses STP-AgriData dataset combining real-orchard imagery with curated web images and contrast/brightness augmentations.
Result: Achieves 86.5% precision, 77.2% recall, 84.3% mAP@0.50, and 53.6% mAP@0.50:0.95 on STP-AgriData, outperforming recent detectors and improving robustness in real orchard environments.
Conclusion: REAS-Det effectively addresses practical challenges in agricultural object detection, particularly for pomelo detection in orchards, demonstrating superior performance and robustness compared to existing methods.
Abstract: Shatian pomelo detection in orchards is essential for yield estimation and lean production, but models tuned to ideal datasets often degrade in practice due to device-dependent tone shifts, illumination changes, large scale variation, and frequent occlusion. We introduce STP-AgriData, a multi-scenario dataset combining real-orchard imagery with curated web images, and apply contrast/brightness augmentations to emulate unstable lighting. To better address scale and occlusion, we propose REAS-Det, featuring Global-Selective Visibility Convolution (GSV-Conv) that expands the visible feature space under global semantic guidance while retaining efficient spatial aggregation, plus C3RFEM, MultiSEAM, and Soft-NMS for refined separation and localization. On STP-AgriData, REAS-Det achieves 86.5% precision, 77.2% recall, 84.3% mAP@0.50, and 53.6% mAP@0.50:0.95, outperforming recent detectors and improving robustness in real orchard environments. The source code is available at: https://github.com/Genk641/REAS-Det.
[455] Color3D: Controllable and Consistent 3D Colorization with Personalized Colorizer
Yecong Wan, Mingwen Shao, Renlong Wu, Wangmeng Zuo
Main category: cs.CV
TL;DR: Color3D is a framework for colorizing static and dynamic 3D scenes from monochrome inputs using personalized colorizers that propagate colors from single key views to ensure consistency while preserving chromatic richness and user control.
Details
Motivation: Existing 3D colorization methods focus only on static scenes and enforce multi-view consistency by averaging colors, which sacrifices chromatic richness and controllability. There's a need for methods that can handle both static and dynamic scenes while preserving color diversity and allowing user-guided control.Method: The approach colorizes a single key view, then fine-tunes a personalized colorizer to propagate colors to novel views and time steps. The colorizer learns scene-specific deterministic color mapping from the reference view and projects consistent colors to other images using its inductive bias. A Lab color space Gaussian splatting representation enables direct reconstruction of colorful 3D scenes.
Result: Extensive experiments across diverse static and dynamic 3D colorization benchmarks show that Color3D delivers more consistent and chromatically rich renderings with precise user control compared to existing methods.
Conclusion: Color3D successfully recasts complex 3D colorization as a more tractable single image paradigm, enabling seamless integration of arbitrary image colorization models with enhanced flexibility and controllability for both static and dynamic 3D scenes.
Abstract: In this work, we present Color3D, a highly adaptable framework for colorizing both static and dynamic 3D scenes from monochromatic inputs, delivering visually diverse and chromatically vibrant reconstructions with flexible user-guided control. In contrast to existing methods that focus solely on static scenarios and enforce multi-view consistency by averaging color variations which inevitably sacrifice both chromatic richness and controllability, our approach is able to preserve color diversity and steerability while ensuring cross-view and cross-time consistency. In particular, the core insight of our method is to colorize only a single key view and then fine-tune a personalized colorizer to propagate its color to novel views and time steps. Through personalization, the colorizer learns a scene-specific deterministic color mapping underlying the reference view, enabling it to consistently project corresponding colors to the content in novel views and video frames via its inherent inductive bias. Once trained, the personalized colorizer can be applied to infer consistent chrominance for all other images, enabling direct reconstruction of colorful 3D scenes with a dedicated Lab color space Gaussian splatting representation. The proposed framework ingeniously recasts complicated 3D colorization as a more tractable single image paradigm, allowing seamless integration of arbitrary image colorization models with enhanced flexibility and controllability. Extensive experiments across diverse static and dynamic 3D colorization benchmarks substantiate that our method can deliver more consistent and chromatically rich renderings with precise user control. Project Page https://yecongwan.github.io/Color3D/.
[456] Restricted Receptive Fields for Face Verification
Kagan Ozturk, Aman Bhatta, Haiyu Wu, Patrick Flynn, Kevin W. Bowyer
Main category: cs.CV
TL;DR: A face similarity metric that decomposes global similarity into patch-level contributions for inherent interpretability, achieving competitive verification performance.
Details
Motivation: Current post-hoc interpretability methods for deep neural networks have uncertain fidelity due to lack of reliable evaluation metrics, motivating the need for inherently interpretable models.Method: Proposes a face similarity metric that breaks down global similarity into contributions from restricted receptive fields, defining similarity as sum of patch-level similarity scores for locally additive explanations.
Result: Achieves competitive verification performance with 28x28 patches within 112x112 face images, and surpasses state-of-the-art methods with 56x56 patches.
Conclusion: The proposed inherently interpretable approach provides locally additive explanations without post-hoc analysis while maintaining competitive performance in face verification.
Abstract: Understanding how deep neural networks make decisions is crucial for analyzing their behavior and diagnosing failure cases. In computer vision, a common approach to improve interpretability is to assign importance to individual pixels using post-hoc methods. Although they are widely used to explain black-box models, their fidelity to the model’s actual reasoning is uncertain due to the lack of reliable evaluation metrics. This limitation motivates an alternative approach, which is to design models whose decision processes are inherently interpretable. To this end, we propose a face similarity metric that breaks down global similarity into contributions from restricted receptive fields. Our method defines the similarity between two face images as the sum of patch-level similarity scores, providing a locally additive explanation without relying on post-hoc analysis. We show that the proposed approach achieves competitive verification performance even with patches as small as 28x28 within 112x112 face images, and surpasses state-of-the-art methods when using 56x56 patches.
[457] InternSVG: Towards Unified SVG Tasks with Multimodal Large Language Models
Haomin Wang, Jinhui Yin, Qi Wei, Wenguang Zeng, Lixin Gu, Shenglong Ye, Zhangwei Gao, Yaohui Wang, Yanting Zhang, Yuanqi Li, Yanwen Guo, Wenhai Wang, Kai Chen, Yu Qiao, Hongjie Zhang
Main category: cs.CV
TL;DR: InternSVG is a unified multimodal large language model framework for SVG understanding, editing, and generation, featuring comprehensive datasets, benchmarks, and specialized training strategies.
Details
Motivation: Address challenges in SVG modeling including fragmented datasets, limited method transferability across tasks, and difficulty handling structural complexity by leveraging MLLMs' strong transfer and generalization capabilities.Method: Proposes InternSVG family with three components: 1) SAgoge dataset (largest comprehensive multimodal SVG dataset), 2) SArena benchmark (standardized evaluation), and 3) InternSVG model with SVG-specific tokens, subword-based embedding initialization, and two-stage training from short static to complex animations.
Result: InternSVG achieves substantial gains and consistently outperforms leading open and proprietary counterparts on SArena and prior benchmarks, demonstrating positive transfer and improved overall performance.
Conclusion: The unified MLLM approach successfully addresses SVG modeling challenges, enabling effective understanding, editing, and generation of both static and dynamic SVG content through comprehensive data, benchmark, and model design.
Abstract: General SVG modeling remains challenging due to fragmented datasets, limited transferability of methods across tasks, and the difficulty of handling structural complexity. In response, we leverage the strong transfer and generalization capabilities of multimodal large language models (MLLMs) to achieve unified modeling for SVG understanding, editing, and generation. We present the InternSVG family, an integrated data-benchmark-model suite. At its core is SAgoge, the largest and most comprehensive multimodal dataset for SVG tasks, encompassing both static graphics and dynamic animations. It covers icons, long-sequence illustrations, scientific diagrams, and dynamic animations, supporting tasks of varied difficulty levels and providing deeper hierarchies with richer attributes compared to previous datasets. Based on this resource, we introduce SArena, a companion benchmark with comprehensive task definitions and standardized evaluation that aligns with the domains and difficulty spectrum covered by SAgoge. Building on these foundations, we propose InternSVG, a unified MLLM for SVG understanding, editing, and generation with SVG-specific special tokens, subword-based embedding initialization, and a two-stage training strategy that progresses from short static SVGs to long-sequence illustrations and complex animations. This unified formulation induces positive transfer and improves overall performance. Experiments on SArena and prior benchmark confirm that InternSVG achieves substantial gains and consistently outperforms leading open and proprietary counterparts.
[458] MS-Mix: Unveiling the Power of Mixup for Multimodal Sentiment Analysis
Hongyu Zhu, Lin Chen, Xin Jin, Mounim A. El-Yacoubi, Mingsheng Shang
Main category: cs.CV
TL;DR: MS-Mix: An emotion-sensitive multimodal augmentation framework that improves multimodal sentiment analysis by preventing contradictory emotion mixing, using sentiment intensity to guide modality mixing ratios, and aligning predictions across modalities.
Details
Motivation: Multimodal sentiment analysis suffers from scarce annotated data. Traditional Mixup augmentation introduces label ambiguity and semantic inconsistency when applied to multimodal settings due to random mixing of samples with contradictory emotions.Method: Proposes MS-Mix with three key components: 1) Sentiment-Aware Sample Selection to prevent mixing contradictory emotions, 2) Sentiment Intensity Guided module using multi-head self-attention to compute modality-specific mixing ratios based on emotional intensities, and 3) Sentiment Alignment Loss with KL-divergence regularization to align predictions across modalities.
Result: Extensive experiments on three benchmark datasets with six state-of-the-art backbones show MS-Mix consistently outperforms existing methods, establishing new standards for robust multimodal sentiment augmentation.
Conclusion: MS-Mix effectively addresses the limitations of traditional augmentation in multimodal sentiment analysis by introducing emotion-aware mechanisms, leading to improved generalization and performance across various backbone architectures.
Abstract: Multimodal Sentiment Analysis (MSA) aims to identify and interpret human emotions by integrating information from heterogeneous data sources such as text, video, and audio. While deep learning models have advanced in network architecture design, they remain heavily limited by scarce multimodal annotated data. Although Mixup-based augmentation improves generalization in unimodal tasks, its direct application to MSA introduces critical challenges: random mixing often amplifies label ambiguity and semantic inconsistency due to the lack of emotion-aware mixing mechanisms. To overcome these issues, we propose MS-Mix, an adaptive, emotion-sensitive augmentation framework that automatically optimizes sample mixing in multimodal settings. The key components of MS-Mix include: (1) a Sentiment-Aware Sample Selection (SASS) strategy that effectively prevents semantic confusion caused by mixing samples with contradictory emotions. (2) a Sentiment Intensity Guided (SIG) module using multi-head self-attention to compute modality-specific mixing ratios dynamically based on their respective emotional intensities. (3) a Sentiment Alignment Loss (SAL) that aligns the prediction distributions across modalities, and incorporates the Kullback-Leibler-based loss as an additional regularization term to train the emotion intensity predictor and the backbone network jointly. Extensive experiments on three benchmark datasets with six state-of-the-art backbones confirm that MS-Mix consistently outperforms existing methods, establishing a new standard for robust multimodal sentiment augmentation. The source code is available at: https://github.com/HongyuZhu-s/MS-Mix.
[459] Paper Copilot: Tracking the Evolution of Peer Review in AI Conferences
Jing Yang, Qiyao Wei, Jiaxin Pei
Main category: cs.CV
TL;DR: Paper Copilot creates digital archives of peer reviews across CS venues, enabling large-scale study of peer review evolution and issues in AI conferences.
Details
Motivation: The rapid growth of AI conferences strains peer-review systems, causing heavy reviewer workloads, expertise mismatches, inconsistent standards, superficial reviews, and limited accountability under compressed timelines, while ad-hoc policy changes create confusion about how papers are accepted.Method: Developed Paper Copilot system that creates durable digital archives of peer reviews across computer-science venues, providing an open dataset for studying peer review at scale, with empirical analysis of ICLR reviews spanning multiple years.
Result: Created infrastructure and dataset supporting reproducible research on peer review evolution, enabling community to track changes, diagnose failure modes, and inform evidence-based improvements for more robust review systems.
Conclusion: Paper Copilot provides essential resources for studying peer review at scale, helping the research community move toward more transparent, reliable, and evidence-based review systems in AI conferences.
Abstract: The rapid growth of AI conferences is straining an already fragile peer-review system, leading to heavy reviewer workloads, expertise mismatches, inconsistent evaluation standards, superficial or templated reviews, and limited accountability under compressed timelines. In response, conference organizers have introduced new policies and interventions to preserve review standards. Yet these ad-hoc changes often create further concerns and confusion about the review process, leaving how papers are ultimately accepted - and how practices evolve across years - largely opaque. We present Paper Copilot, a system that creates durable digital archives of peer reviews across a wide range of computer-science venues, an open dataset that enables researchers to study peer review at scale, and a large-scale empirical analysis of ICLR reviews spanning multiple years. By releasing both the infrastructure and the dataset, Paper Copilot supports reproducible research on the evolution of peer review. We hope these resources help the community track changes, diagnose failure modes, and inform evidence-based improvements toward a more robust, transparent, and reliable peer-review system.
[460] Vision-Centric 4D Occupancy Forecasting and Planning via Implicit Residual World Models
Jianbiao Mei, Yu Yang, Xuemeng Yang, Licheng Wen, Jiajun Lv, Botian Shi, Yong Liu
Main category: cs.CV
TL;DR: IR-WM is an Implicit Residual World Model for autonomous driving that focuses on modeling state changes rather than full scene reconstruction, using BEV representations and residual prediction to improve efficiency and planning accuracy.
Details
Motivation: Current vision-centric world models for autonomous driving waste capacity on redundant static background reconstruction. The authors aim to create a more efficient model that focuses on dynamic changes and state evolution.Method: IR-WM first creates a BEV representation of current state from visual input. It uses previous timestep’s BEV features as temporal prior and predicts only residual changes conditioned on ego-vehicle actions and scene context. An alignment module addresses error accumulation, and different forecasting-planning coupling schemes are explored.
Result: On nuScenes benchmark, IR-WM achieves top performance in both 4D occupancy forecasting and trajectory planning, demonstrating improved planning accuracy through implicit future state generation.
Conclusion: Focusing on residual modeling of state changes rather than full scene reconstruction leads to more efficient world models that significantly improve autonomous driving planning performance.
Abstract: End-to-end autonomous driving systems increasingly rely on vision-centric world models to understand and predict their environment. However, a common ineffectiveness in these models is the full reconstruction of future scenes, which expends significant capacity on redundantly modeling static backgrounds. To address this, we propose IR-WM, an Implicit Residual World Model that focuses on modeling the current state and evolution of the world. IR-WM first establishes a robust bird’s-eye-view representation of the current state from the visual observation. It then leverages the BEV features from the previous timestep as a strong temporal prior and predicts only the “residual”, i.e., the changes conditioned on the ego-vehicle’s actions and scene context. To alleviate error accumulation over time, we further apply an alignment module to calibrate semantic and dynamic misalignments. Moreover, we investigate different forecasting-planning coupling schemes and demonstrate that the implicit future state generated by world models substantially improves planning accuracy. On the nuScenes benchmark, IR-WM achieves top performance in both 4D occupancy forecasting and trajectory planning.
[461] Decoupled Complementary Spectral-Spatial Learning for Background Representation Enhancement in Hyperspectral Anomaly Detection
Wenping Jin, Li Zhu, Fei Guo
Main category: cs.CV
TL;DR: Proposes a decoupled complementary spectral-spatial learning framework for hyperspectral anomaly detection that enhances background representations through two-stage training with spectral enhancement and spatial complementary learning.
Details
Motivation: To improve hyperspectral anomaly detection by enhancing background representations through complementary spectral and spatial learning, enabling universal deployment without per-scene retraining or parameter tuning.Method: Two-stage training: (1) train spectral enhancement network via reverse distillation for robust spectral representations, (2) freeze spectral branch as teacher and train spatial branch as “rebellious student” with decorrelation objectives to capture overlooked spatial patterns. Uses reconstruction regularization to prevent noise learning.
Result: Experiments on HAD100 benchmark show substantial improvements over baselines with modest computational overhead. Enhanced features can be plugged into parameter-free detectors like Reed-Xiaoli (RX) detector.
Conclusion: The complementary learning paradigm effectively enhances background representations for hyperspectral anomaly detection, enabling efficient universal deployment without per-scene retraining.
Abstract: A recent class of hyperspectral anomaly detection methods can be trained once on background datasets and then deployed universally without per-scene retraining or parameter tuning, showing strong efficiency and robustness. Building upon this paradigm, we propose a decoupled complementary spectral–spatial learning framework for background representation enhancement. The framework follows a two-stage training strategy: (1) we first train a spectral enhancement network via reverse distillation to obtain robust background spectral representations; and (2) we then freeze the spectral branch as a teacher and train a spatial branch as a complementary student (the “rebellious student”) to capture spatial patterns overlooked by the teacher. Complementary learning is achieved through decorrelation objectives that reduce representational redundancy between the two branches, together with reconstruction regularization to prevent the student from learning irrelevant noise. After training, the framework jointly enhances background representations from both spectral and spatial perspectives, and the resulting enhanced features can be plugged into parameter-free, training-free detectors (e.g., the Reed–Xiaoli (RX) detector) for test-time deployment without per-scene retraining or parameter tuning. Experiments on the HAD100 benchmark demonstrate substantial improvements over representative baselines with modest computational overhead, validating the effectiveness of the proposed complementary learning paradigm. Our code is publicly available at https://github.com/xjpp2016/FERS.
[462] An Intelligent Multi-task Supply Chain Model Based on Bio-inspired Networks
Mehdi Khaleghi, Sobhan Sheykhivand, Nastaran Khaleghi, Sebelan Danishvar
Main category: cs.CV
TL;DR: A novel Chebyshev ensemble geometric network (Ch-EGN) combining convolutional and geometric deep learning for supply chain sustainability analysis, achieving high accuracy in risk management and product classification tasks.
Details
Motivation: To enhance supply chain sustainability and performance efficiency through better risk management and product classification using advanced deep learning techniques that can capture complex dependencies in supply chain networks.Method: Proposes a hybrid Chebyshev ensemble geometric network (Ch-EGN) that combines convolutional and geometric deep learning to leverage information dependencies in supply chain data and derive invisible states of samples.
Result: Achieved 98.95% average accuracy for risk management (delivery status prediction), 100% for 5-product group classification, 98.07% for 4-product relation classification, and 92.37% for 25-company relation classification on SupplyGraph and DataCo datasets.
Conclusion: The proposed Ch-EGN ensemble network demonstrates superior performance in supply chain sustainability analysis, outperforming state-of-the-art approaches in risk management and classification tasks.
Abstract: The sustainability of supply chain plays a key role in achieving optimal performance in controlling the supply chain. The management of risks that occur in a supply chain is a fundamental problem for the purpose of developing the sustainability of the network and elevating the performance efficiency of the supply chain. The correct classification of products is another essential element in a sustainable supply chain. Acknowledging recent breakthroughs in the context of deep networks, several architectural options have been deployed to analyze supply chain datasets. A novel geometric deep network is used to propose an ensemble deep network. The proposed Chebyshev ensemble geometric network (Ch-EGN) is a hybrid convolutional and geometric deep learning. This network is proposed to leverage the information dependencies in supply chain to derive invisible states of samples in the database. The functionality of the proposed deep network is assessed on the two different databases. The SupplyGraph Dataset and DataCo are considered in this research. The prediction of delivery status of DataCo supply chain is done for risk administration. The product classification and edge classification are performed using the SupplyGraph database to enhance the sustainability of the supply network. An average accuracy of 98.95% is obtained for the ensemble network for risk management. The average accuracy of 100% and 98.07% are obtained for sustainable supply chain in terms of 5 product group classification and 4 product relation classification, respectively. The average accuracy of 92.37% is attained for 25 company relation classification. The results confirm an average improvement and efficiency of the proposed method compared to the state-of-the-art approaches.
[463] PALM: A Dataset and Baseline for Learning Multi-subject Hand Prior
Zicong Fan, Edoardo Remelli, David Dimond, Fadime Sener, Liuhao Ge, Bugra Tekin, Cem Keskin, Shreyas Hampali
Main category: cs.CV
TL;DR: PALM dataset provides 13k high-quality hand scans from 263 subjects with 90k multi-view images, enabling realistic single-image hand avatar personalization through PALM-Net using inverse rendering.
Details
Motivation: Creating high-quality personalized hand avatars from images is challenging due to complex geometry, appearance, and articulation under unconstrained lighting and limited views. Lack of diverse datasets with accurate 3D geometry and high-resolution multiview imagery has limited progress in this area.Method: Presents PALM dataset with 13k hand scans from 263 subjects and 90k multi-view images capturing diverse skin tones, ages, and geometries. Introduces PALM-Net baseline model that learns multi-subject prior over hand geometry and material properties via physically based inverse rendering.
Result: PALM provides a large-scale, diverse real-world resource for hand modeling. PALM-Net enables realistic, relightable single-image hand avatar personalization by leveraging the learned prior over hand geometry and material properties.
Conclusion: PALM dataset addresses the critical need for diverse, high-quality hand data, while PALM-Net demonstrates practical utility for single-image hand avatar creation, advancing research in personalized hand modeling and related areas.
Abstract: The ability to grasp objects, signal with gestures, and share emotion through touch all stem from the unique capabilities of human hands. Yet creating high-quality personalized hand avatars from images remains challenging due to complex geometry, appearance, and articulation, particularly under unconstrained lighting and limited views. Progress has also been limited by the lack of datasets that jointly provide accurate 3D geometry, high-resolution multiview imagery, and a diverse population of subjects. To address this, we present PALM, a large-scale dataset comprising 13k high-quality hand scans from 263 subjects and 90k multi-view images, capturing rich variation in skin tone, age, and geometry. To show its utility, we present a baseline PALM-Net, a multi-subject prior over hand geometry and material properties learned via physically based inverse rendering, enabling realistic, relightable single-image hand avatar personalization. PALM’s scale and diversity make it a valuable real-world resource for hand modeling and related research.
[464] Constructing the Umwelt: Cognitive Planning through Belief-Intent Co-Evolution
Shiyao Sang
Main category: cs.CV
TL;DR: A novel cognitive architecture for autonomous driving that challenges the need for high-fidelity world reconstruction, proposing instead that planning emerges from cognitive consistency between internal intentional models and physical reality.
Details
Motivation: The paper challenges the prevailing assumption in end-to-end autonomous driving that high-performance planning requires high-fidelity world reconstruction. Inspired by cognitive science, it proposes that intelligence emerges from cognitive consistency between an agent's internal intentional world and physical reality rather than from pixel-level objective fidelity.Method: Proposes the Mental Bayesian Causal World Model (MBCWM) instantiated as Tokenized Intent World Model (TIWM), a cognitive computing architecture that synthesizes von Uexküll’s Umwelt theory, neural assembly hypothesis, and triple causal model (symbolic deduction, probabilistic induction, force dynamics) into an end-to-end embodied planning system. Features Belief-Intent Co-Evolution mechanism and demonstrates on nuPlan benchmark.
Result: Experimental results in open-loop validation show the Belief-Intent Co-Evolution mechanism effectively enhances planning performance. In closed-loop simulations, the system exhibits emergent human-like cognitive behaviors including map affordance understanding, free exploration, and self-recovery strategies. Cognitive consistency emerges as the core learning mechanism where belief and intent spontaneously form self-organizing equilibrium through implicit computational replay.
Conclusion: TIWM offers a neuro-symbolic, cognition-first alternative to reconstruction-based planners, establishing a new direction: planning as active understanding rather than passive reaction. It demonstrates that high-performance planning can emerge from cognitive consistency rather than high-fidelity world reconstruction.
Abstract: This paper challenges a prevailing epistemological assumption in End-to-End Autonomous Driving: that high-performance planning necessitates high-fidelity world reconstruction. Inspired by cognitive science, we propose the Mental Bayesian Causal World Model (MBCWM) and instantiate it as the Tokenized Intent World Model (TIWM), a novel cognitive computing architecture. Its core philosophy posits that intelligence emerges not from pixel-level objective fidelity, but from the Cognitive Consistency between the agent’s internal intentional world and physical reality. By synthesizing von Uexküll’s $\textit{Umwelt}$ theory, the neural assembly hypothesis, and the triple causal model (integrating symbolic deduction, probabilistic induction, and force dynamics) into an end-to-end embodied planning system, we demonstrate the feasibility of this paradigm on the nuPlan benchmark. Experimental results in open-loop validation confirm that our Belief-Intent Co-Evolution mechanism effectively enhances planning performance. Crucially, in closed-loop simulations, the system exhibits emergent human-like cognitive behaviors, including map affordance understanding, free exploration, and self-recovery strategies. We identify Cognitive Consistency as the core learning mechanism: during long-term training, belief (state understanding) and intent (future prediction) spontaneously form a self-organizing equilibrium through implicit computational replay, achieving semantic alignment between internal representations and physical world affordances. TIWM offers a neuro-symbolic, cognition-first alternative to reconstruction-based planners, establishing a new direction: planning as active understanding, not passive reaction.
[465] Explainable Cross-Disease Reasoning for Cardiovascular Risk Assessment from Low-Dose Computed Tomography
Yifei Zhang, Jiashuo Zhang, Mojtaba Safari, Xiaofeng Yang, Liang Zhao
Main category: cs.CV
TL;DR: An explainable cross-disease reasoning framework for joint cardiopulmonary risk assessment from low-dose chest CT scans, using agentic reasoning to connect pulmonary findings to cardiovascular implications with natural-language rationales.
Details
Motivation: Low-dose chest CT captures both pulmonary and cardiac structures, but existing approaches treat these domains independently, overlooking their physiological interplay and shared imaging biomarkers. There's a need for unified, interpretable assessment that emulates clinical diagnostic thinking.Method: Proposes an Explainable Cross-Disease Reasoning Framework with three components: 1) Pulmonary Perception Module summarizing lung abnormalities, 2) Agentic Pulmonary-to-Cardiac Reasoning Module inferring cardiovascular implications using medical knowledge, and 3) Cardiac Feature Extractor encoding structural biomarkers. These outputs are fused for holistic cardiovascular risk prediction with natural-language rationales.
Result: On NLST cohort, achieves state-of-the-art performance for CVD screening (AUC=0.919) and mortality prediction (AUC=0.838), outperforming single-disease and purely image-based baselines. Provides human-verifiable reasoning aligning with cardiological understanding.
Conclusion: Establishes a unified, explainable paradigm for cardiovascular analysis from LDCT, bridging image-based prediction with mechanism-based medical interpretation through interpretable cross-disease reasoning.
Abstract: Low-dose chest computed tomography (LDCT) inherently captures both pulmonary and cardiac structures, offering a unique opportunity for joint assessment of lung and cardiovascular health. However, most existing approaches treat these domains as independent tasks, overlooking their physiological interplay and shared imaging biomarkers. We propose an Explainable Cross-Disease Reasoning Framework that enables interpretable cardiopulmonary risk assessment from a single LDCT scan. The framework introduces an agentic reasoning process that emulates clinical diagnostic thinking: first perceiving pulmonary findings, then reasoning through established medical knowledge, and finally deriving a cardiovascular judgment with a natural-language rationale. It integrates three components: a Pulmonary Perception Module that summarizes lung abnormalities, an Agentic Pulmonary-to-Cardiac Reasoning Module that infers their cardiovascular implications, and a Cardiac Feature Extractor that encodes structural biomarkers. Their outputs are fused to produce a holistic cardiovascular risk prediction that is both accurate and physiologically grounded. Experiments on the NLST cohort demonstrate that the proposed framework achieves state-of-the-art performance for CVD screening (AUC=0.919) and mortality prediction (AUC=0.838), outperforming single-disease and purely image-based baselines. Beyond quantitative gains, the framework provides human-verifiable reasoning that aligns with cardiological understanding, revealing coherent links between pulmonary abnormalities and cardiac stress mechanisms. Overall, this work establishes a unified and explainable paradigm for cardiovascular analysis from LDCT, bridging the gap between image-based prediction and mechanism-based medical interpretation.
[466] Building Egocentric Procedural AI Assistant: Methods, Benchmarks, and Challenges
Junlong Li, Huaiyuan Xu, Sijie Cheng, Kejun Wu, Kim-Hui Yap, Lap-Pui Chau, Yi Wang
Main category: cs.CV
TL;DR: Survey paper introducing Egocentric Procedural AI Assistant (EgoProceAssist) - a new research direction for first-person procedural task assistance, covering core tasks, enabling dimensions, taxonomy, and evaluation of current VLM methods.
Details
Motivation: To bridge the gap between recent advances in vision-language models (VLMs) and egocentric perception research by creating AI assistants that can support daily procedural tasks from a first-person perspective.Method: 1) Identifies three core tasks: egocentric procedural error detection, learning, and question answering; 2) Introduces two enabling dimensions: real-time streaming video understanding and proactive interaction; 3) Creates taxonomy and comprehensive review; 4) Conducts novel experiments evaluating representative VLM-based methods.
Result: Provides comprehensive taxonomy and framework for EgoProceAssist, identifies gaps between proposed assistant capabilities and current VLM methods, and establishes evaluation benchmarks through experiments.
Conclusion: EgoProceAssist represents an emerging research direction with significant potential for real-world daily activity assistance, but current VLM methods have limitations that need to be addressed through future research in multimodal understanding and interaction.
Abstract: Driven by recent advances in vision-language models (VLMs) and egocentric perception research, the emerging topic of an egocentric procedural AI assistant (EgoProceAssist) is introduced to step-by-step support daily procedural tasks in a first-person view. In this paper, we start by identifying three core tasks in EgoProceAssist: egocentric procedural error detection, egocentric procedural learning, and egocentric procedural question answering, then introduce two enabling dimensions: real-time and streaming video understanding, and proactive interaction in procedural contexts. We define these tasks within a new taxonomy as the EgoProceAssist’s essential functions and illustrate how they can be deployed in real-world scenarios for daily activity assistants. Specifically, our work encompasses a comprehensive review of current techniques, relevant datasets, and evaluation metrics across these five core areas. To clarify the gap between the proposed EgoProceAssist and existing VLM-based assistants, we conduct novel experiments to provide a comprehensive evaluation of representative VLM-based methods. Through these findings and our technical analysis, we discuss the challenges ahead and suggest future research directions. Furthermore, an exhaustive list of this study is publicly available in an active repository that continuously collects the latest work: https://github.com/z1oong/Building-Egocentric-Procedural-AI-Assistant.
[467] LookSharp: Attention Entropy Minimization for Test-Time Adaptation
Yash Mali, Evan Shelhamer
Main category: cs.CV
TL;DR: LookSharp: Test-time adaptation method that minimizes entropy of CLS-to-patch attention in transformer final layer to improve robustness on distribution shifts while maintaining clean data performance.
Details
Motivation: Current test-time adaptation methods primarily use entropy minimization over output distributions, but transformer models compute intermediate attention distributions that could provide additional adaptation signals for handling distribution shifts.Method: Proposes LookSharp, which minimizes the entropy of CLS-to-patch attention in the final transformer layer during test-time adaptation. This encourages the model to maintain focused attention on shifted data, complementing traditional output entropy minimization.
Result: Attention entropy minimization improves robustness on ImageNet-C distribution shifts. The method is complementary to output entropy minimization and maintains performance on clean data.
Conclusion: Minimizing attention entropy in transformers provides an effective test-time adaptation objective that enhances robustness to distribution shifts while preserving clean data performance, offering a novel approach beyond traditional output-based adaptation.
Abstract: Test-time adaptation (TTA) updates models during inference to reduce error on distribution shifts. While entropy minimization over the output distribution has proven effective as a TTA loss, we study using the intermediate distributions computed by transformers in the attention mechanism. We propose LookSharp, which minimizes the entropy of CLS-to-patch attention in the final layer as a novel TTA objective, encouraging the model to maintain focused attention on shifted data. We demonstrate that attention entropy minimization improves robustness on ImageNet-C. We also show that it is complementary to output entropy minimization and maintains performance on clean data.
[468] MOTION: ML-Assisted On-Device Low-Latency Motion Recognition
Veeramani Pugazhenthi, Wei-Hsiang Chu, Junwei Lu, Jadyn N. Miyahira, Mahdi Eslamimehr, Pratik Satam, Rozhin Yasaei, Soheil Salehi
Main category: cs.CV
TL;DR: Efficient on-device gesture recognition using triaxial accelerometer data and AutoML pipelines for medical monitoring applications
Details
Motivation: Need for low-latency gesture recognition on tiny embedded devices for medical monitoring applications like fall detection, rehabilitation tracking, and patient supervision, requiring fast and efficient movement tracking while minimizing false alarmsMethod: Use AutoML pipelines to extract important features from triaxial accelerometer data segments, train multiple lightweight ML algorithms on extracted features, implement on WeBe Band wearable device with capable MCU for on-device processing
Result: Neural network provided best balance between accuracy, latency, and memory use; reliable real-time gesture recognition achieved on WeBe Band with potential for secure, fast medical monitoring solutions
Conclusion: Efficient motion-based models using only accelerometer sensors can enable reliable real-time gesture recognition on embedded devices for medical monitoring applications
Abstract: The use of tiny devices capable of low-latency gesture recognition is gaining momentum in everyday human-computer interaction and especially in medical monitoring fields. Embedded solutions such as fall detection, rehabilitation tracking, and patient supervision require fast and efficient tracking of movements while avoiding unwanted false alarms. This study presents an efficient solution on how to build very efficient motion-based models only using triaxial accelerometer sensors. We explore the capability of the AutoML pipelines to extract the most important features from the data segments. This approach also involves training multiple lightweight machine learning algorithms using the extracted features. We use WeBe Band, a multi-sensor wearable device that is equipped with a powerful enough MCU to effectively perform gesture recognition entirely on the device. Of the models explored, we found that the neural network provided the best balance between accuracy, latency, and memory use. Our results also demonstrate that reliable real-time gesture recognition can be achieved in WeBe Band, with great potential for real-time medical monitoring solutions that require a secure and fast response time.
[469] GrndCtrl: Grounding World Models via Self-Supervised Reward Alignment
Haoyang He, Jay Patrikar, Dong-Ki Kim, Max Smith, Daniel McGann, Ali-akbar Agha-mohammadi, Shayegan Omidshafiei, Sebastian Scherer
Main category: cs.CV
TL;DR: RLWG is a self-supervised post-training framework that aligns pretrained video world models with geometric grounding using verifiable rewards, enabling stable embodied navigation.
Details
Motivation: Current video world models generate realistic environments but lack geometric grounding, limiting their usefulness for navigation tasks that require spatial coherence and stability.Method: Introduces RLWG framework using geometric and perceptual rewards (pose cycle-consistency, depth reprojection, temporal coherence) with GrndCtrl adaptation method based on Group Relative Policy Optimization (GRPO) for post-training alignment.
Result: Achieves superior spatial coherence and navigation stability over supervised fine-tuning in outdoor environments, maintaining stable trajectories and consistent geometry.
Conclusion: RLWG bridges generative pretraining and grounded behavior through verifiable rewards, similar to post-training alignment in language models, enabling geometrically grounded world models for embodied navigation.
Abstract: Recent advances in video world modeling have enabled large-scale generative models to simulate embodied environments with high visual fidelity, providing strong priors for prediction, planning, and control. Yet, despite their realism, these models often lack geometric grounding, limiting their use in navigation tasks that require spatial coherence and stability. We introduce Reinforcement Learning with World Grounding (RLWG), a self-supervised post-training framework that aligns pretrained world models with a physically verifiable structure through geometric and perceptual rewards. Analogous to reinforcement learning from verifiable feedback (RLVR) in language models, RLWG can use multiple rewards that measure pose cycle-consistency, depth reprojection, and temporal coherence. We instantiate this framework with GrndCtrl, a reward-aligned adaptation method based on Group Relative Policy Optimization (GRPO), yielding world models that maintain stable trajectories, consistent geometry, and reliable rollouts for embodied navigation. Like post-training alignment in large language models, GrndCtrl leverages verifiable rewards to bridge generative pretraining and grounded behavior, achieving superior spatial coherence and navigation stability over supervised fine-tuning in outdoor environments.
[470] Breaking Scale Anchoring: Frequency Representation Learning for Accurate High-Resolution Inference from Low-Resolution Training
Wenshuo Wang, Fan Zhang
Main category: cs.CV
TL;DR: The paper introduces Scale Anchoring problem in zero-shot super-resolution spatiotemporal forecasting and proposes Frequency Representation Learning to enable error reduction with increasing resolution.
Details
Motivation: Existing approaches incorrectly interpret maintaining similar error across resolutions as successful generalization, but models should actually reduce error as resolution increases. The fundamental limitation is that low-resolution data has constrained Nyquist frequency, preventing models from processing unseen high-frequency components during high-resolution inference.Method: Proposes Frequency Representation Learning (FRL) - an architecture-agnostic approach using resolution-aligned frequency representations and spectral consistency training to stabilize frequency response across different Nyquist frequencies.
Result: FRL-enhanced variants show more stable frequency response in high-frequency bands on grids with higher Nyquist frequencies, allowing errors to decrease with resolution and significantly outperform baselines with modest computational overhead.
Conclusion: Identifies Scale Anchoring as a distinct problem from existing issues and demonstrates that FRL effectively addresses it by enabling proper error reduction with increasing resolution in spatiotemporal forecasting tasks.
Abstract: Zero-Shot Super-Resolution Spatiotemporal Forecasting requires a deep learning model to be trained on low-resolution data and deployed for inference on high-resolution. Existing studies consider maintaining similar error across different resolutions as indicative of successful multi-resolution generalization. However, deep learning models serving as alternatives to numerical solvers should reduce error as resolution increases. The fundamental limitation is, the upper bound of physical law frequencies that low-resolution data can represent is constrained by its Nyquist frequency, making it difficult for models to process signals containing unseen frequency components during high-resolution inference. This results in errors being anchored at low resolution, incorrectly interpreted as successful generalization. We define this fundamental phenomenon as a new problem distinct from existing issues: Scale Anchoring. Therefore, we propose architecture-agnostic Frequency Representation Learning. It alleviates Scale Anchoring through resolution-aligned frequency representations and spectral consistency training: on grids with higher Nyquist frequencies, the frequency response in high-frequency bands of FRL-enhanced variants is more stable. This allows errors to decrease with resolution and significantly outperform baselines within our task and resolution range, while incurring only modest computational overhead.
[471] Fine-tuning an ECG Foundation Model to Predict Coronary CT Angiography Outcomes
Yujie Xiao, Qinghao Zhao, Gongzheng Tang, Hao Zhang, Zhuoran Kan, Deyun Zhang, Jun Li, Guangkun Nie, Xiaocheng Fang, Haoyu Wang, Shun Huang, Tong Liu, Jian Liu, Kangyin Chen, Shenda Hong
Main category: cs.CV
TL;DR: AI-ECG model developed to detect severe coronary artery stenosis using CCTA as reference standard, showing moderate performance and potential clinical utility for CAD risk screening.
Details
Motivation: Coronary artery disease is a major global health burden with limited scalable screening tools. While CCTA is a first-line diagnostic modality, it has resource and radiation constraints. AI-ECG could provide a complementary, more accessible approach for CAD risk stratification.Method: Developed and validated an AI-ECG model using CCTA as the reference standard to estimate severe (≥70%) or complete (≥99%) stenosis in the four major coronary arteries. Conducted internal and external validation, and evaluated performance in clinical cohorts with longitudinal follow-up.
Result: Model achieved AUC values of 0.706-0.744 in internal validation and 0.673-0.714 in external validation. Performance remained stable across subgroups including those with clinically normal ECGs. Vessel-specific risk stratification showed distinct separation between high-risk and low-risk groups in time-to-event analyses.
Conclusion: AI-ECG shows feasibility as a complementary CAD risk screening tool with potential clinical utility. The approach warrants prospective evaluation and could provide a more accessible alternative to resource-intensive imaging modalities.
Abstract: Coronary artery disease (CAD) remains a major global public health burden, yet scalable tools for risk screening are limited. Although coronary computed tomography angiography (CCTA) is a first-line non-invasive diagnostic modality, its widespread use is constrained by resource requirements and radiation exposure. Artificial intelligence–enabled electrocardiography (AI-ECG) may provide a complementary approach for CAD risk stratification. We developed and validated an AI-ECG model using CCTA as the reference standard to estimate severe ($\geq 70%$) or complete ($\geq 99%$) stenosis in the four major coronary arteries. In internal validation, the model achieved area under the receiver operating characteristic curve (AUC) values of 0.706–0.744 across vessels and demonstrated consistent performance in external validation (AUCs: 0.673–0.714). Discrimination remained stable among individuals with clinically normal ECGs and across demographic and clinical subgroups. In a dedicated clinical cohort with longitudinal follow-up, vessel-specific risk stratification based on model-predicted probabilities yielded distinct separation between high-risk and low-risk groups in time-to-event analyses using Kaplan–Meier curves, while decision curve analysis suggested potential clinical utility as an adjunctive screening tool. Explainable analyses highlighted waveform patterns associated with elevated predicted risk. These findings support the feasibility of AI-ECG for complementary CAD risk screening and warrant prospective evaluation.
[472] GTAvatar: Bridging Gaussian Splatting and Texture Mapping for Relightable and Editable Gaussian Avatars
Kelian Baert, Mae Younes, Francois Bourel, Marc Christie, Adnane Boukhayma
Main category: cs.CV
TL;DR: A method combining Gaussian Splatting accuracy with UV texture mapping for editable head avatars from monocular video, enabling intuitive appearance/geometry editing via texture mapping without additional optimization.
Details
Motivation: Gaussian Splatting enables photorealistic head avatar reconstruction but lacks intuitive editability compared to traditional triangle mesh methods with UV texture mapping. There's a need to combine the accuracy of Gaussian Splatting with the editability of UV-based approaches.Method: Embed each canonical Gaussian primitive’s local frame into UV space patches on a template mesh efficiently. Reconstruct continuous editable material head textures from single monocular video on conventional UV domain. Use efficient physically based reflectance model for relighting and editing intrinsic material maps.
Result: Demonstrates accurate reconstructions, high-quality relighting results, and intuitive controls for modifying avatar appearance and geometry via texture mapping without additional optimization. Extensive comparisons show superiority over state-of-the-art methods.
Conclusion: Successfully combines Gaussian Splatting fidelity with UV texture mapping intuitiveness, enabling editable head avatars from monocular video with relighting capabilities and intuitive appearance/geometry controls.
Abstract: Recent advancements in Gaussian Splatting have enabled increasingly accurate reconstruction of photorealistic head avatars, opening the door to numerous applications in visual effects, videoconferencing, and virtual reality. This, however, comes with the lack of intuitive editability offered by traditional triangle mesh-based methods. In contrast, we propose a method that combines the accuracy and fidelity of 2D Gaussian Splatting with the intuitiveness of UV texture mapping. By embedding each canonical Gaussian primitive’s local frame into a patch in the UV space of a template mesh in a computationally efficient manner, we reconstruct continuous editable material head textures from a single monocular video on a conventional UV domain. Furthermore, we leverage an efficient physically based reflectance model to enable relighting and editing of these intrinsic material maps. Through extensive comparisons with state-of-the-art methods, we demonstrate the accuracy of our reconstructions, the quality of our relighting results, and the ability to provide intuitive controls for modifying an avatar’s appearance and geometry via texture mapping without additional optimization.
[473] MomaGraph: State-Aware Unified Scene Graphs with Vision-Language Model for Embodied Task Planning
Yuanchen Ju, Yongyuan Liang, Yen-Jen Wang, Nandiraju Gireesh, Yuanliang Ju, Seungjae Lee, Qiao Gu, Elvis Hsieh, Furong Huang, Koushil Sreenath
Main category: cs.CV
TL;DR: MomaGraph is a unified scene representation for embodied agents that integrates spatial-functional relationships and part-level interactive elements, with a dataset, benchmark, and 7B vision-language model for task-oriented scene graph prediction and zero-shot planning.
Details
Motivation: Mobile manipulators need compact, semantically rich scene representations that capture object locations, functionality, and actionable parts. Prior work separates spatial/functional relations, treats scenes as static, and overlooks task-relevant information.Method: Introduces MomaGraph unified representation, creates MomaGraph-Scenes dataset (large-scale annotated task-driven scene graphs), MomaGraph-Bench evaluation suite, and MomaGraph-R1 (7B vision-language model trained with RL on the dataset) for task-oriented scene graph prediction and zero-shot planning.
Result: MomaGraph-R1 achieves 71.6% accuracy on the benchmark (+11.4% over best baseline), shows strong generalization across public benchmarks, and transfers effectively to real-robot experiments.
Conclusion: MomaGraph provides a comprehensive framework for embodied scene understanding and planning, with demonstrated state-of-the-art performance and real-world applicability.
Abstract: Mobile manipulators in households must both navigate and manipulate. This requires a compact, semantically rich scene representation that captures where objects are, how they function, and which parts are actionable. Scene graphs are a natural choice, yet prior work often separates spatial and functional relations, treats scenes as static snapshots without object states or temporal updates, and overlooks information most relevant for accomplishing the current task. To address these limitations, we introduce MomaGraph, a unified scene representation for embodied agents that integrates spatial-functional relationships and part-level interactive elements. However, advancing such a representation requires both suitable data and rigorous evaluation, which have been largely missing. We thus contribute MomaGraph-Scenes, the first large-scale dataset of richly annotated, task-driven scene graphs in household environments, along with MomaGraph-Bench, a systematic evaluation suite spanning six reasoning capabilities from high-level planning to fine-grained scene understanding. Built upon this foundation, we further develop MomaGraph-R1, a 7B vision-language model trained with reinforcement learning on MomaGraph-Scenes. MomaGraph-R1 predicts task-oriented scene graphs and serves as a zero-shot task planner under a Graph-then-Plan framework. Extensive experiments demonstrate that our model achieves state-of-the-art results among open-source models, reaching 71.6% accuracy on the benchmark (+11.4% over the best baseline), while generalizing across public benchmarks and transferring effectively to real-robot experiments.
[474] ALIGN: Advanced Query Initialization with LiDAR-Image Guidance for Occlusion-Robust 3D Object Detection
Janghyun Baek, Mincheol Chang, Seokha Moon, Seung Joon Lee, Jinkyu Kim
Main category: cs.CV
TL;DR: ALIGN improves 3D object detection by using LiDAR and image guidance for better query initialization, addressing occlusion and crowded scene challenges.
Details
Motivation: Existing query-based 3D object detection methods suffer from inefficient query usage and reduced accuracy for occluded or crowded objects due to suboptimal query initialization strategies like random sampling or BEV heatmap-based sampling.Method: Proposes ALIGN with three components: 1) Occlusion-aware Center Estimation integrating LiDAR geometry and image semantics, 2) Adaptive Neighbor Sampling generating object candidates from LiDAR clustering with supplemental sampling, and 3) Dynamic Query Balancing between foreground/background regions.
Result: On nuScenes benchmark, ALIGN consistently improves multiple state-of-the-art detectors by up to +0.9 mAP and +1.2 NDS, particularly in challenging scenes with occlusions or dense crowds.
Conclusion: ALIGN provides an effective occlusion-robust, object-aware query initialization approach that enhances 3D object detection performance in complex scenarios.
Abstract: Recent query-based 3D object detection methods using camera and LiDAR inputs have shown strong performance, but existing query initialization strategies,such as random sampling or BEV heatmap-based sampling, often result in inefficient query usage and reduced accuracy, particularly for occluded or crowded objects. To address this limitation, we propose ALIGN (Advanced query initialization with LiDAR and Image GuidaNce), a novel approach for occlusion-robust, object-aware query initialization. Our model consists of three key components: (i) Occlusion-aware Center Estimation (OCE), which integrates LiDAR geometry and image semantics to estimate object centers accurately (ii) Adaptive Neighbor Sampling (ANS), which generates object candidates from LiDAR clustering and supplements each object by sampling spatially and semantically aligned points around it and (iii) Dynamic Query Balancing (DQB), which adaptively balances queries between foreground and background regions. Our extensive experiments on the nuScenes benchmark demonstrate that ALIGN consistently improves performance across multiple state-of-the-art detectors, achieving gains of up to +0.9 mAP and +1.2 NDS, particularly in challenging scenes with occlusions or dense crowds. Our code will be publicly available upon publication.
[475] Block-Recurrent Dynamics in Vision Transformers
Mozes Jacobs, Thomas Fel, Richard Hakim, Alessandra Brondetta, Demba Ba, T. Andy Keller
Main category: cs.CV
TL;DR: Vision Transformers exhibit block-recurrent depth structure where computation can be accurately rewritten using far fewer distinct blocks applied recurrently, enabling dynamical systems analysis.
Details
Motivation: To provide a mechanistic account of Vision Transformers' computational phenomenology by interpreting Transformer depth as a well-characterized dynamical flow, moving beyond architectural cues to understand the emergent structure.Method: Introduces Block-Recurrent Hypothesis (BRH) and trains Recurrent Approximations to Phase-structured TransfORmers (Raptor) - block-recurrent surrogates of pretrained ViTs that use k ≪ L distinct blocks applied recurrently to approximate original computation.
Result: Demonstrates BRH empirically: Raptor recovers 96% of DINOv2 ImageNet-1k linear probe accuracy in only 2 blocks at equivalent computational cost. Shows directional convergence into class-dependent angular basins, token-specific dynamics, and collapse to low rank updates in late depth.
Conclusion: A compact recurrent program emerges along ViT depth, revealing a low-complexity normative solution that enables studying these models through principled dynamical systems analysis.
Abstract: As Vision Transformers (ViTs) become standard vision backbones, a mechanistic account of their computational phenomenology is essential. Despite architectural cues that hint at dynamical structure, there is no settled framework that interprets Transformer depth as a well-characterized flow. In this work, we introduce the Block-Recurrent Hypothesis (BRH), arguing that trained ViTs admit a block-recurrent depth structure such that the computation of the original $L$ blocks can be accurately rewritten using only $k \ll L$ distinct blocks applied recurrently. Across diverse ViTs, between-layer representational similarity matrices suggest few contiguous phases. To determine whether these phases reflect genuinely reusable computation, we train block-recurrent surrogates of pretrained ViTs: Recurrent Approximations to Phase-structured TransfORmers (Raptor). In small-scale, we demonstrate that stochastic depth and training promote recurrent structure and subsequently correlate with our ability to accurately fit Raptor. We then provide an empirical existence proof for BRH by training a Raptor model to recover $96%$ of DINOv2 ImageNet-1k linear probe accuracy in only 2 blocks at equivalent computational cost. Finally, we leverage our hypothesis to develop a program of Dynamical Interpretability. We find i) directional convergence into class-dependent angular basins with self-correcting trajectories under small perturbations, ii) token-specific dynamics, where cls executes sharp late reorientations while patch tokens exhibit strong late-stage coherence toward their mean direction, and iii) a collapse to low rank updates in late depth, consistent with convergence to low-dimensional attractors. Altogether, we find a compact recurrent program emerges along ViT depth, pointing to a low-complexity normative solution that enables these models to be studied through principled dynamical systems analysis.
[476] SuperiorGAT: Graph Attention Networks for Sparse LiDAR Point Cloud Reconstruction in Autonomous Systems
Khalfalla Awedat, Mohamed Abidalrekab, Gurcan Comert, Mustafa Ayad
Main category: cs.CV
TL;DR: SuperiorGAT uses graph attention networks to reconstruct missing elevation information in sparse LiDAR point clouds by modeling scans as beam-aware graphs with gated residual fusion.
Details
Motivation: LiDAR perception in autonomous systems faces limitations due to fixed vertical beam resolution and beam dropout from environmental occlusions, which degrade point cloud quality and perception accuracy.Method: Models LiDAR scans as beam-aware graphs, uses graph attention networks with gated residual fusion and feed-forward refinement to reconstruct missing elevation information without increasing network depth.
Result: Achieves lower reconstruction error and improved geometric consistency compared to PointNet-based models and deeper GAT baselines across diverse KITTI environments, preserving structural integrity with minimal vertical distortion.
Conclusion: Architectural refinement offers computationally efficient method for improving LiDAR resolution without requiring additional sensor hardware, addressing beam dropout through intelligent reconstruction.
Abstract: LiDAR-based perception in autonomous systems is constrained by fixed vertical beam resolution and further compromised by beam dropout resulting from environmental occlusions. This paper introduces SuperiorGAT, a graph attention-based framework designed to reconstruct missing elevation information in sparse LiDAR point clouds. By modeling LiDAR scans as beam-aware graphs and incorporating gated residual fusion with feed-forward refinement, SuperiorGAT enables accurate reconstruction without increasing network depth. To evaluate performance, structured beam dropout is simulated by removing every fourth vertical scanning beam. Extensive experiments across diverse KITTI environments, including Person, Road, Campus, and City sequences, demonstrate that SuperiorGAT consistently achieves lower reconstruction error and improved geometric consistency compared to PointNet-based models and deeper GAT baselines. Qualitative X-Z projections further confirm the model’s ability to preserve structural integrity with minimal vertical distortion. These results suggest that architectural refinement offers a computationally efficient method for improving LiDAR resolution without requiring additional sensor hardware.
[477] G2P: Gaussian-to-Point Attribute Alignment for Boundary-Aware 3D Semantic Segmentation
Hojun Song, Chae-yeong Song, Jeong-hun Hong, Chaewon Moon, Dong-hwi Kim, Gahyeon Kim, Soo Ye Kim, Yiyi Liao, Jaehyup Lee, Sang-hyo Park
Main category: cs.CV
TL;DR: G2P transfers appearance-aware attributes from 3D Gaussian Splatting to point clouds for improved semantic segmentation by addressing geometric ambiguity and enabling precise boundary localization.
Details
Motivation: Point clouds have sparse and irregular distributions with limited appearance evidence, making geometry-only features insufficient to distinguish objects with similar shapes but different appearances (color, texture, material). Existing methods struggle with geometric ambiguity and boundary localization in complex 3D scenes.Method: Proposes Gaussian-to-Point (G2P) which transfers appearance-aware attributes from 3D Gaussian Splatting to point clouds. Addresses misalignment between optimized Gaussians and original point geometry by establishing point-wise correspondences. Uses Gaussian opacity attributes to resolve geometric ambiguity and Gaussian scale attributes for precise boundary localization.
Result: Achieves superior performance on standard benchmarks with significant improvements on geometrically challenging classes. Works without any 2D or language supervision.
Conclusion: G2P effectively transfers appearance-aware attributes from 3D Gaussian Splatting to enhance point cloud segmentation, overcoming limitations of geometry-only features and improving performance on challenging cases.
Abstract: Semantic segmentation on point clouds is critical for 3D scene understanding. However, sparse and irregular point distributions provide limited appearance evidence, making geometry-only features insufficient to distinguish objects with similar shapes but distinct appearances (e.g., color, texture, material). We propose Gaussian-to-Point (G2P), which transfers appearance-aware attributes from 3D Gaussian Splatting to point clouds for more discriminative and appearance-consistent segmentation. Our G2P address the misalignment between optimized Gaussians and original point geometry by establishing point-wise correspondences. By leveraging Gaussian opacity attributes, we resolve the geometric ambiguity that limits existing models. Additionally, Gaussian scale attributes enable precise boundary localization in complex 3D scenes. Extensive experiments demonstrate that our approach achieves superior performance on standard benchmarks and shows significant improvements on geometrically challenging classes, all without any 2D or language supervision.
[478] 3D Wavelet-Based Structural Priors for Controlled Diffusion in Whole-Body Low-Dose PET Denoising
Peiyuan Jing, Yue Yang, Chun-Wun Cheng, Zhenxuan Zhang, Liutao Yang, Thiago V. Lima, Klaus Strobel, Antoine Leimgruber, Angelica Aviles-Rivero, Guang Yang, Javier Montoya
Main category: cs.CV
TL;DR: WCC-Net is a 3D diffusion-based framework for low-dose PET denoising that uses wavelet representations to provide structural guidance, improving anatomical consistency while reducing noise.
Details
Motivation: Low-dose PET imaging reduces radiation exposure but suffers from increased noise that degrades image quality. While diffusion models show strong denoising capability, their stochastic nature makes it challenging to enforce anatomically consistent structures, especially in low signal-to-noise regimes and volumetric whole-body imaging.Method: Proposes Wavelet-Conditioned ControlNet (WCC-Net), a fully 3D diffusion-based framework that introduces explicit frequency-domain structural priors via wavelet representations. It injects wavelet-based structural guidance into a frozen pretrained diffusion backbone through a lightweight control branch, decoupling anatomical structure from noise while preserving generative expressiveness and 3D structural continuity.
Result: WCC-Net consistently outperforms CNN-, GAN-, and diffusion-based baselines. On internal 1/20-dose test set, it improves PSNR by +1.21 dB and SSIM by +0.008 over strong diffusion baseline, while reducing structural distortion (GMSD) and intensity error (NMAE). It also generalizes robustly to unseen dose levels (1/50 and 1/4), achieving superior quantitative performance and improved volumetric anatomical consistency.
Conclusion: WCC-Net effectively addresses the challenge of anatomical consistency in diffusion-based PET denoising by incorporating wavelet-based structural guidance, demonstrating strong performance across various dose levels while maintaining 3D structural continuity.
Abstract: Low-dose Positron Emission Tomography (PET) imaging reduces patient radiation exposure but suffers from increased noise that degrades image quality and diagnostic reliability. Although diffusion models have demonstrated strong denoising capability, their stochastic nature makes it challenging to enforce anatomically consistent structures, particularly in low signal-to-noise regimes and volumetric whole-body imaging. We propose Wavelet-Conditioned ControlNet (WCC-Net), a fully 3D diffusion-based framework that introduces explicit frequency-domain structural priors via wavelet representations to guide volumetric PET denoising. By injecting wavelet-based structural guidance into a frozen pretrained diffusion backbone through a lightweight control branch, WCC-Net decouples anatomical structure from noise while preserving generative expressiveness and 3D structural continuity. Extensive experiments demonstrate that WCC-Net consistently outperforms CNN-, GAN-, and diffusion-based baselines. On the internal 1/20-dose test set, WCC-Net improves PSNR by +1.21 dB and SSIM by +0.008 over a strong diffusion baseline, while reducing structural distortion (GMSD) and intensity error (NMAE). Moreover, WCC-Net generalizes robustly to unseen dose levels (1/50 and 1/4), achieving superior quantitative performance and improved volumetric anatomical consistency.
[479] Moonworks Lunara Aesthetic Dataset
Yan Wang, Sayeef Abdullah, Partho Hassan, Sabit Hassan
Main category: cs.CV
TL;DR: The paper introduces the Lunara Aesthetic Dataset - a high-quality, diverse artistic style dataset with human-refined prompts and structured annotations, released under Apache 2.0 license.
Details
Motivation: To address the lack of high-quality, aesthetically-focused datasets with diverse artistic styles and transparent licensing for research and commercial use.Method: Created dataset using Moonworks Lunara model to generate images embodying distinct aesthetic styles from various global regions, with human-refined prompts and structured annotations describing objects, attributes, relationships, and stylistic cues.
Result: Produced a first-of-its-kind dataset with substantially higher aesthetic scores than existing aesthetics-focused and general-purpose datasets, featuring diverse regional aesthetics and comprehensive annotations.
Conclusion: The Lunara Aesthetic Dataset provides a valuable resource for aesthetic research with high-quality, diverse artistic styles, transparent licensing, and comprehensive annotations.
Abstract: The dataset spans diverse artistic styles, including regionally grounded aesthetics from the Middle East, Northern Europe, East Asia, and South Asia, alongside general categories such as sketch and oil painting. All images are generated using the Moonworks Lunara model and intentionally crafted to embody distinct, high-quality aesthetic styles, yielding a first-of-its-kind dataset with substantially higher aesthetic scores, exceeding even aesthetics-focused datasets, and general-purpose datasets by a larger margin. Each image is accompanied by a human-refined prompt and structured annotations that jointly describe salient objects, attributes, relationships, and stylistic cues. Unlike large-scale web-derived datasets that emphasize breadth over precision, the Lunara Aesthetic Dataset prioritizes aesthetic quality, stylistic diversity, and licensing transparency, and is released under the Apache 2.0 license to support research and unrestricted academic and commercial use.
[480] SUG-Occ: An Explicit Semantics and Uncertainty Guided Sparse Learning Framework for Real-Time 3D Occupancy Prediction
Hanlin Wu, Pengfei Lin, Ehsan Javanmardi, Naren Bao, Bo Qian, Hao Si, Manabu Tsukada
Main category: cs.CV
TL;DR: SUG-Occ is a sparse learning framework for efficient 3D semantic occupancy prediction that uses semantic and uncertainty guidance to reduce computation while maintaining accuracy.
Details
Motivation: 3D semantic occupancy prediction is crucial for autonomous driving scene understanding but suffers from prohibitive computation and memory overhead, making real-time deployment challenging.Method: Uses semantic and uncertainty priors to suppress free space projections, employs unsigned distance encoding for geometric consistency, cascade sparse completion with hyper cross sparse convolution, and object contextual representation mask decoder for efficient query-context interactions.
Result: Achieves 7.34% improvement in accuracy and 57.8% gain in efficiency on SemanticKITTI benchmark compared to baselines.
Conclusion: SUG-Occ effectively addresses computational challenges in 3D semantic occupancy prediction through sparse learning techniques while maintaining geometric and semantic completeness.
Abstract: As autonomous driving moves toward full scene understanding, 3D semantic occupancy prediction has emerged as a crucial perception task, offering voxel-level semantics beyond traditional detection and segmentation paradigms. However, such a refined representation for scene understanding incurs prohibitive computation and memory overhead, posing a major barrier to practical real-time deployment. To address this, we propose SUG-Occ, an explicit Semantics and Uncertainty Guided Sparse Learning Enabled 3D Occupancy Prediction Framework, which exploits the inherent sparsity of 3D scenes to reduce redundant computation while maintaining geometric and semantic completeness. Specifically, we first utilize semantic and uncertainty priors to suppress projections from free space during view transformation while employing an explicit unsigned distance encoding to enhance geometric consistency, producing a structurally consistent sparse 3D representation. Secondly, we design an cascade sparse completion module via hyper cross sparse convolution and generative upsampling to enable efficiently coarse-to-fine reasoning. Finally, we devise an object contextual representation (OCR) based mask decoder that aggregates global semantic context from sparse features and refines voxel-wise predictions via lightweight query-context interactions, avoiding expensive attention operations over volumetric features. Extensive experiments on SemanticKITTI benchmark demonstrate that the proposed approach outperforms the baselines, achieving a 7.34/% improvement in accuracy and a 57.8% gain in efficiency.
[481] Generating metamers of human scene understanding
Ritik Raina, Abe Leite, Alexandros Graikos, Seoyoung Ahn, Dimitris Samaras, Gregory J. Zelinsky
Main category: cs.CV
TL;DR: MetamerGen is a latent diffusion model that generates image metamers aligned with human scene understanding by combining high-resolution foveated information from fixations with low-resolution peripheral gist information.
Details
Motivation: Human vision constructs scene understanding by combining low-resolution peripheral gist information with high-resolution foveated details from fixations. The paper aims to create a tool that can generate scenes aligned with latent human scene representations to better understand human visual perception.Method: MetamerGen uses a latent diffusion model with a dual-stream representation of foveated scenes. It combines DINOv2 tokens that fuse detailed features from fixated areas with peripherally degraded features capturing scene context. The model tackles the novel image-to-image synthesis problem of generating from both high and low resolution foveated inputs.
Result: The model generates image metamers that align with human scene representations. Behavioral experiments show participants perceive generated images as “same” as originals when conditioned on viewers’ own fixations. High-level semantic alignment most strongly predicts metamerism when conditioned on actual viewer fixations.
Conclusion: MetamerGen is a powerful tool for understanding human scene understanding. It can generate metamers even with random fixations, but achieves strongest perceptual alignment when conditioned on viewers’ actual fixated regions, revealing specific features at multiple visual processing levels that contribute to human judgments.
Abstract: Human vision combines low-resolution “gist” information from the visual periphery with sparse but high-resolution information from fixated locations to construct a coherent understanding of a visual scene. In this paper, we introduce MetamerGen, a tool for generating scenes that are aligned with latent human scene representations. MetamerGen is a latent diffusion model that combines peripherally obtained scene gist information with information obtained from scene-viewing fixations to generate image metamers for what humans understand after viewing a scene. Generating images from both high and low resolution (i.e. “foveated”) inputs constitutes a novel image-to-image synthesis problem, which we tackle by introducing a dual-stream representation of the foveated scenes consisting of DINOv2 tokens that fuse detailed features from fixated areas with peripherally degraded features capturing scene context. To evaluate the perceptual alignment of MetamerGen generated images to latent human scene representations, we conducted a same-different behavioral experiment where participants were asked for a “same” or “different” response between the generated and the original image. With that, we identify scene generations that are indeed metamers for the latent scene representations formed by the viewers. MetamerGen is a powerful tool for understanding scene understanding. Our proof-of-concept analyses uncovered specific features at multiple levels of visual processing that contributed to human judgments. While it can generate metamers even conditioned on random fixations, we find that high-level semantic alignment most strongly predicts metamerism when the generated scenes are conditioned on viewers’ own fixated regions.
[482] GO-MLVTON: Garment Occlusion-Aware Multi-Layer Virtual Try-On with Diffusion Models
Yang Yu, Yunze Deng, Yige Zhang, Yanjie Xiao, Youkun Ou, Wenhao Hu, Mingchao Li, Bin Feng, Wenyu Liu, Dandan Zheng, Jingdong Chen
Main category: cs.CV
TL;DR: GO-MLVTON is a novel multi-layer virtual try-on method that addresses the challenge of dressing multiple garment layers with realistic deformation and occlusion handling using Garment Occlusion Learning and StableDiffusion-based garment morphing.
Details
Motivation: Existing virtual try-on methods focus on single-layer or multi-garment scenarios but neglect multi-layer try-on where garments are worn in layers with realistic occlusion relationships. The key challenge is modeling occlusion between inner and outer garments to prevent interference from redundant inner garment features.Method: Proposes GO-MLVTON with two main modules: 1) Garment Occlusion Learning module to learn occlusion relationships between garment layers, and 2) StableDiffusion-based Garment Morphing & Fitting module to deform and fit garments onto the human body. Also introduces the MLG dataset and a new evaluation metric called Layered Appearance Coherence Difference (LACD).
Result: Extensive experiments demonstrate state-of-the-art performance in multi-layer virtual try-on, producing high-quality multi-layer try-on results with realistic garment deformation and layering.
Conclusion: GO-MLVTON successfully addresses the multi-layer virtual try-on problem by learning occlusion relationships and using diffusion-based garment fitting, establishing a new benchmark for this challenging task with the proposed MLG dataset and LACD metric.
Abstract: Existing image-based virtual try-on (VTON) methods primarily focus on single-layer or multi-garment VTON, neglecting multi-layer VTON (ML-VTON), which involves dressing multiple layers of garments onto the human body with realistic deformation and layering to generate visually plausible outcomes. The main challenge lies in accurately modeling occlusion relationships between inner and outer garments to reduce interference from redundant inner garment features. To address this, we propose GO-MLVTON, the first multi-layer VTON method, introducing the Garment Occlusion Learning module to learn occlusion relationships and the StableDiffusion-based Garment Morphing & Fitting module to deform and fit garments onto the human body, producing high-quality multi-layer try-on results. Additionally, we present the MLG dataset for this task and propose a new metric named Layered Appearance Coherence Difference (LACD) for evaluation. Extensive experiments demonstrate the state-of-the-art performance of GO-MLVTON. Project page: https://upyuyang.github.io/go-mlvton/.
[483] Federated Balanced Learning
Jiaze Li, Haoran Xu, Wanyi Wu, Changwei Wang, Shuaiguang Li, Jianzhong Ju, Zhenbo Luo, Jian Luan, Youyang Qu, Longxiang Gao, Xudong Yang, Lumin Xing
Main category: cs.CV
TL;DR: Federated Balanced Learning (FBL) addresses client drift in non-iid federated learning by achieving sample balance on client side through knowledge filling/sampling using edge-side generation models.
Details
Motivation: In federated learning with non-iid data, client drift seriously affects model performance. Previous methods correct the already-deviated global model using loss/gradient approaches, but overlook the impact of client sample distribution.Method: Proposes Federated Balanced Learning (FBL) that achieves sample balance on client side through knowledge filling and knowledge sampling using edge-side generation models. Includes Knowledge Alignment Strategy to bridge synthetic-real data gap, Knowledge Drop Strategy for regularization, and scales to complex scenarios with heterogeneous client methods.
Result: Numerous experiments show the method outperforms state-of-the-art baselines in federated learning with non-iid data distributions.
Conclusion: FBL effectively prevents client drift by addressing sample imbalance at the client side through generative approaches, offering a scalable solution for real-world federated learning scenarios.
Abstract: Federated learning is a paradigm of joint learning in which clients collaborate by sharing model parameters instead of data. However, in the non-iid setting, the global model experiences client drift, which can seriously affect the final performance of the model. Previous methods tend to correct the global model that has already deviated based on the loss function or gradient, overlooking the impact of the client samples. In this paper, we rethink the role of the client side and propose Federated Balanced Learning, i.e., FBL, to prevent this issue from the beginning through sample balance on the client side. Technically, FBL allows unbalanced data on the client side to achieve sample balance through knowledge filling and knowledge sampling using edge-side generation models, under the limitation of a fixed number of data samples on clients. Furthermore, we design a Knowledge Alignment Strategy to bridge the gap between synthetic and real data, and a Knowledge Drop Strategy to regularize our method. Meanwhile, we scale our method to real and complex scenarios, allowing different clients to adopt various methods, and extend our framework to further improve performance. Numerous experiments show that our method outperforms state-of-the-art baselines. The code is released upon acceptance.
[484] ThermoSplat: Cross-Modal 3D Gaussian Splatting with Feature Modulation and Geometry Decoupling
Zhaoqi Su, Shihai Chen, Xinyan Lin, Liqin Huang, Zhipeng Su, Xiaoqiang Lu
Main category: cs.CV
TL;DR: ThermoSplat extends 3D Gaussian Splatting to multi-spectral RGB+thermal reconstruction using spectrum-aware feature modulation and adaptive geometry decoupling for robust cross-modal scene representation.
Details
Motivation: Multi-modal scene reconstruction with RGB and thermal infrared data is crucial for robust environmental perception across varying lighting/weather conditions, but current 3DGS extensions struggle to effectively leverage complementary multi-modal information and handle cross-modal correlations and physical discrepancies.Method: Proposes ThermoSplat with: 1) Spectrum-Aware Adaptive Modulation that dynamically conditions shared latent features on thermal structural priors; 2) Modality-Adaptive Geometric Decoupling that learns independent opacity offsets and executes separate rasterization for thermal branch; 3) Hybrid rendering pipeline integrating explicit Spherical Harmonics with implicit neural decoding.
Result: Extensive experiments on RGBT-Scenes dataset demonstrate state-of-the-art rendering quality across both visible and thermal spectrums.
Conclusion: ThermoSplat enables deep spectral-aware reconstruction through active feature modulation and adaptive geometry decoupling, effectively handling complex structural correlations and physical discrepancies between RGB and thermal modalities.
Abstract: Multi-modal scene reconstruction integrating RGB and thermal infrared data is essential for robust environmental perception across diverse lighting and weather conditions. However, extending 3D Gaussian Splatting (3DGS) to multi-spectral scenarios remains challenging. Current approaches often struggle to fully leverage the complementary information of multi-modal data, typically relying on mechanisms that either tend to neglect cross-modal correlations or leverage shared representations that fail to adaptively handle the complex structural correlations and physical discrepancies between spectrums. To address these limitations, we propose ThermoSplat, a novel framework that enables deep spectral-aware reconstruction through active feature modulation and adaptive geometry decoupling. First, we introduce a Spectrum-Aware Adaptive Modulation that dynamically conditions shared latent features on thermal structural priors, effectively guiding visible texture synthesis with reliable cross-modal geometric cues. Second, to accommodate modality-specific geometric inconsistencies, we propose a Modality-Adaptive Geometric Decoupling scheme that learns independent opacity offsets and executes an independent rasterization pass for the thermal branch. Additionally, a hybrid rendering pipeline is employed to integrate explicit Spherical Harmonics with implicit neural decoding, ensuring both semantic consistency and high-frequency detail preservation. Extensive experiments on the RGBT-Scenes dataset demonstrate that ThermoSplat achieves state-of-the-art rendering quality across both visible and thermal spectrums.
[485] Visual Prompt-Agnostic Evolution
Junze Wang, Lei Fan, Dezheng Zhang, Weipeng Jing, Donglin Di, Yang Song, Sidong Liu, Cong Cong
Main category: cs.CV
TL;DR: PAE improves Visual Prompt Tuning by addressing unstable training dynamics through frequency-aware initialization, shared Koopman operators for cross-layer coordination, and Lyapunov-inspired regularization.
Details
Motivation: Existing Visual Prompt Tuning (VPT) methods suffer from unstable training dynamics with gradient oscillations, shallow-layer prompt stagnation, and deep-layer high-variance oscillations, leading to cross-layer mismatch that slows convergence and degrades performance.Method: Proposes Prompt-Agnostic Evolution (PAE) with three components: 1) Frequency-aware initialization using frequency shortcut patterns the backbone inherently exploits, 2) Shared Koopman operator for coherent cross-layer evolution via global linear transformation, and 3) Lyapunov-inspired regularizer to constrain error amplification during training.
Result: PAE achieves average 1.41× convergence speedup and 1-3% accuracy improvement on 25 datasets across multiple downstream tasks. It’s prompt-agnostic, lightweight, and integrates seamlessly with diverse VPT variants without backbone modification or inference changes.
Conclusion: PAE effectively addresses training instability in VPT through frequency-aware initialization, cross-layer coordination, and stability regularization, making prompt tuning more efficient and effective while maintaining compatibility with existing VPT frameworks.
Abstract: Visual Prompt Tuning (VPT) adapts a frozen Vision Transformer (ViT) to downstream tasks by inserting a small number of learnable prompt tokens into the token sequence at each layer. However, we observe that existing VPT variants often suffer from unstable training dynamics, characterized by gradient oscillations. A layer-wise analysis reveals that shallow-layer prompts tend to stagnate early, while deeper-layer prompts exhibit high-variance oscillations, leading to cross-layer mismatch. These issues slow convergence and degrade final performance. To address these challenges, we propose Prompt-Agnostic Evolution ($\mathtt{PAE}$), which strengthens vision prompt tuning by explicitly modeling prompt dynamics. From a frequency-domain perspective, we initialize prompts in a task-aware direction by uncovering and propagating frequency shortcut patterns that the backbone inherently exploits for recognition. To ensure coherent evolution across layers, we employ a shared Koopman operator that imposes a global linear transformation instead of uncoordinated, layer-specific updates. Finally, inspired by Lyapunov stability theory, we introduce a regularizer that constrains error amplification during evolution. Extensive experiments show that $\mathtt{PAE}$ accelerates convergence with an average $1.41\times$ speedup and improves accuracy by 1-3% on 25 datasets across multiple downstream tasks. Beyond performance, $\mathtt{PAE}$ is prompt-agnostic and lightweight, and it integrates seamlessly with diverse VPT variants without backbone modification or inference-time changes.
[486] CAF-Mamba: Mamba-Based Cross-Modal Adaptive Attention Fusion for Multimodal Depression Detection
Bowen Zhou, Marc-André Fiedler, Ayoub Al-Hamadi
Main category: cs.CV
TL;DR: CAF-Mamba: A Mamba-based cross-modal adaptive attention fusion framework for depression detection that captures explicit and implicit cross-modal interactions with dynamic modality weighting.
Details
Motivation: Current deep learning approaches for depression detection rely on limited feature types, overlook explicit cross-modal interactions, and use simple concatenation or static weighting for fusion, limiting their effectiveness.Method: Proposes CAF-Mamba, a novel framework using Mamba architecture with cross-modal adaptive attention fusion that captures both explicit and implicit cross-modal interactions and dynamically adjusts modality contributions through modality-wise attention mechanism.
Result: Outperforms existing methods on two in-the-wild benchmark datasets (LMVD and D-Vlog), achieving state-of-the-art performance for depression detection.
Conclusion: CAF-Mamba effectively addresses limitations of current multimodal fusion approaches for depression detection by enabling more effective cross-modal interaction and dynamic modality weighting.
Abstract: Depression is a prevalent mental health disorder that severely impairs daily functioning and quality of life. While recent deep learning approaches for depression detection have shown promise, most rely on limited feature types, overlook explicit cross-modal interactions, and employ simple concatenation or static weighting for fusion. To overcome these limitations, we propose CAF-Mamba, a novel Mamba-based cross-modal adaptive attention fusion framework. CAF-Mamba not only captures cross-modal interactions explicitly and implicitly, but also dynamically adjusts modality contributions through a modality-wise attention mechanism, enabling more effective multimodal fusion. Experiments on two in-the-wild benchmark datasets, LMVD and D-Vlog, demonstrate that CAF-Mamba consistently outperforms existing methods and achieves state-of-the-art performance. Our code is available at https://github.com/zbw-zhou/CAF-Mamba.
[487] Q-Hawkeye: Reliable Visual Policy Optimization for Image Quality Assessment
Wulin Xie, Rui Dai, Ruidong Ding, Kaikui Liu, Xiangxiang Chu, Xinwen Hou, Jie Wen
Main category: cs.CV
TL;DR: Q-Hawkeye is an RL-based reliable visual policy optimization framework for Image Quality Assessment that addresses reliability limitations in existing MLLM-based methods through uncertainty-aware dynamic optimization and perception-aware optimization.
Details
Motivation: Existing RL-based IQA methods using MLLMs have two key reliability limitations: (1) they apply uniform advantage weighting despite varying prediction stability across training samples, amplifying noisy signals from unstable samples; (2) they emphasize text-grounded reasoning while overlooking the model's visual perception ability of image content.Method: Proposes Q-Hawkeye with two main components: (1) Uncertainty-Aware Dynamic Optimization that estimates predictive uncertainty using variance of predicted scores across multiple rollouts and uses this uncertainty to reweight each sample’s update strength; (2) Perception-Aware Optimization that constructs paired inputs of degraded images and their originals, and introduces an Implicit Perception Loss to constrain quality judgments to genuine visual evidence.
Result: Extensive experiments demonstrate that Q-Hawkeye outperforms state-of-the-art methods and generalizes better across multiple datasets.
Conclusion: Q-Hawkeye provides a more reliable RL-based visual policy optimization framework for IQA by addressing both uncertainty and perception limitations in existing MLLM approaches.
Abstract: Image Quality Assessment (IQA) predicts perceptual quality scores consistent with human judgments. Recent RL-based IQA methods built on MLLMs focus on generating visual quality descriptions and scores, ignoring two key reliability limitations: (i) although the model’s prediction stability varies significantly across training samples, existing GRPO-based methods apply uniform advantage weighting, thereby amplifying noisy signals from unstable samples in gradient updates; (ii) most works emphasize text-grounded reasoning over images while overlooking the model’s visual perception ability of image content. In this paper, we propose Q-Hawkeye, an RL-based reliable visual policy optimization framework that redesigns the learning signal through unified Uncertainty-Aware Dynamic Optimization and Perception-Aware Optimization. Q-Hawkeye estimates predictive uncertainty using the variance of predicted scores across multiple rollouts and leverages this uncertainty to reweight each sample’s update strength, stabilizing policy optimization. To strengthen perceptual reliability, we construct paired inputs of degraded images and their original images and introduce an Implicit Perception Loss that constrains the model to ground its quality judgments in genuine visual evidence. Extensive experiments demonstrate that Q-Hawkeye outperforms state-of-the-art methods and generalizes better across multiple datasets. The code and models will be made available.
[488] LatentLens: Revealing Highly Interpretable Visual Tokens in LLMs
Benno Krojer, Shravan Nayak, Oscar Mañas, Vaibhav Adlakha, Desmond Elliott, Siva Reddy, Marius Mosbach
Main category: cs.CV
TL;DR: LatentLens is a novel interpretability method that maps visual token representations in VLMs to natural language descriptions by comparing them to contextualized textual representations from a large text corpus.
Details
Motivation: To understand why LLMs can readily process visual tokens when transformed into VLMs, and to develop interpretability methods that reveal what is encoded in visual token representations at every layer of LLM processing.Method: LatentLens encodes a large text corpus and stores contextualized token representations for each token. Visual token representations are then compared to these textual representations using nearest neighbor search, with top-k matches providing natural language descriptions of the visual tokens.
Result: Evaluation on 10 different VLMs shows that LatentLens substantially outperforms commonly used methods like LogitLens, with the majority of visual tokens being interpretable across all studied models and layers. The descriptions are semantically meaningful and provide fine-grained interpretations.
Conclusion: LatentLens provides new evidence for alignment between vision and language representations, offering a powerful tool for analyzing latent representations in multimodal models and opening new directions for interpretability research.
Abstract: Transforming a large language model (LLM) into a Vision-Language Model (VLM) can be achieved by mapping the visual tokens from a vision encoder into the embedding space of an LLM. Intriguingly, this mapping can be as simple as a shallow MLP transformation. To understand why LLMs can so readily process visual tokens, we need interpretability methods that reveal what is encoded in the visual token representations at every layer of LLM processing. In this work, we introduce LatentLens, a novel approach for mapping latent representations to descriptions in natural language. LatentLens works by encoding a large text corpus and storing contextualized token representations for each token in that corpus. Visual token representations are then compared to their contextualized textual representations, with the top-k nearest neighbor representations providing descriptions of the visual token. We evaluate this method on 10 different VLMs, showing that commonly used methods, such as LogitLens, substantially underestimate the interpretability of visual tokens. With LatentLens instead, the majority of visual tokens are interpretable across all studied models and all layers. Qualitatively, we show that the descriptions produced by LatentLens are semantically meaningful and provide more fine-grained interpretations for humans compared to individual tokens. More broadly, our findings contribute new evidence on the alignment between vision and language representations, opening up new directions for analyzing latent representations.
[489] Moonworks Lunara Aesthetic II: An Image Variation Dataset
Yan Wang, Partho Hassan, Samiha Sadeka, Nada Soliman, Sayeef Abdullah, Sabit Hassan
Main category: cs.CV
TL;DR: Lunara Aesthetic II is a publicly released image dataset for evaluating contextual consistency in image generation/editing systems, featuring 2,854 anchor-linked variation pairs with identity-preserving contextual transformations.
Details
Motivation: To address the need for controlled evaluation and learning of contextual consistency in modern image generation and editing systems, providing interpretable supervision signals for identity preservation during contextual changes.Method: Created a dataset of 2,854 anchor-linked variation pairs from original art and photographs, applying contextual transformations (illumination, weather, viewpoint, scene composition, color tone, mood) while preserving underlying identity.
Result: The dataset shows high identity stability, strong target attribute realization, and robust aesthetic profile exceeding large-scale web datasets, released under Apache 2.0 license for public use.
Conclusion: Lunara Aesthetic II provides a valuable resource for benchmarking, fine-tuning, and analyzing contextual generalization, identity preservation, and edit robustness in image generation systems with interpretable supervision.
Abstract: We introduce Lunara Aesthetic II, a publicly released, ethically sourced image dataset designed to support controlled evaluation and learning of contextual consistency in modern image generation and editing systems. The dataset comprises 2,854 anchor-linked variation pairs derived from original art and photographs created by Moonworks. Each variation pair applies contextual transformations, such as illumination, weather, viewpoint, scene composition, color tone, or mood; while preserving a stable underlying identity. Lunara Aesthetic II operationalizes identity-preserving contextual variation as a supervision signal while also retaining Lunara’s signature high aesthetic scores. Results show high identity stability, strong target attribute realization, and a robust aesthetic profile that exceeds large-scale web datasets. Released under the Apache 2.0 license, Lunara Aesthetic II is intended for benchmarking, fine-tuning, and analysis of contextual generalization, identity preservation, and edit robustness in image generation and image-to-image systems with interpretable, relational supervision. The dataset is publicly available at: https://huggingface.co/datasets/moonworks/lunara-aesthetic-image-variations.
[490] ReasonEdit: Editing Vision-Language Models using Human Reasoning
Jiaxing Qiu, Kaihua Hou, Roxana Daneshjou, Ahmed Alaa, Thomas Hartvigsen
Main category: cs.CV
TL;DR: ReasonEdit: First VLM editor that incorporates human reasoning explanations during editing for reasoning-heavy visual question answering tasks, using codebook storage and topology-balanced multimodal embeddings.
Details
Motivation: Existing vision-language model editors don't handle reasoning-heavy tasks that require humans and models to reason about images, creating a gap for practical model editing setups.Method: Proposes ReasonEdit with continuous storage of human reasoning in a codebook, retrieving relevant facts during inference using novel topology-balanced multimodal embedding method inspired by network science.
Result: Achieves state-of-the-art editing performance across four VLMs on multiple rationale-based visual question answering datasets, showing human reasoning during editing greatly improves edit generalization.
Conclusion: First VLM editor to incorporate human reasoning explanations, demonstrating significant improvements in edit generalization for reasoning-heavy visual tasks.
Abstract: Model editing aims to correct errors in large, pretrained models without altering unrelated behaviors. While some recent works have edited vision-language models (VLMs), no existing editors tackle reasoning-heavy tasks, which typically require humans and models to reason about images. We therefore propose ReasonEdit, the first VLM editor to let users explain their reasoning during editing, introducing a new, practical model editing setup. ReasonEdit continuously stores human reasoning in a codebook, and retrieves only relevant facts during inference using a novel topology-balanced multimodal embedding method inspired by network science. Across four VLMs on multiple rationale-based visual question answering datasets, ReasonEdit achieves state-of-the-art editing performance, ultimately showing that using human reasoning during editing greatly improves edit generalization.
[491] UniReason 1.0: A Unified Reasoning Framework for World Knowledge Aligned Image Generation and Editing
Dianyi Wang, Chaofan Ma, Feng Han, Size Wu, Wei Song, Yibin Wang, Zhixiong Zhang, Tianhang Wang, Siyuan Wang, Zhongyu Wei, Jiaqi Wang
Main category: cs.CV
TL;DR: UniReason is a unified multimodal framework that integrates text-to-image generation and image editing through complementary reasoning paradigms, using world knowledge-enhanced textual reasoning and visual refinement via self-reflection.
Details
Motivation: Current unified multimodal models struggle with complex synthesis tasks requiring deep reasoning and treat text-to-image generation and image editing as isolated capabilities rather than interconnected reasoning steps.Method: Proposes UniReason framework with two complementary reasoning paradigms: 1) world knowledge-enhanced textual reasoning for inferring implicit knowledge during generation, and 2) editing capabilities for fine-grained visual refinement via self-reflection. Unifies generation and editing within shared architecture, and constructs large-scale reasoning-centric dataset (~300k samples) covering five major knowledge domains.
Result: Extensive experiments show UniReason achieves advanced performance on reasoning-intensive benchmarks (WISE, KrisBench, UniREditBench) while maintaining superior general synthesis capabilities.
Conclusion: UniReason successfully unifies generation and editing through complementary reasoning paradigms, mirroring human cognitive processes of planning followed by refinement, and demonstrates strong performance on reasoning-intensive multimodal tasks.
Abstract: Unified multimodal models often struggle with complex synthesis tasks that demand deep reasoning, and typically treat text-to-image generation and image editing as isolated capabilities rather than interconnected reasoning steps. To address this, we propose UniReason, a unified framework that harmonizes these two tasks through two complementary reasoning paradigms. We incorporate world knowledge-enhanced textual reasoning into generation to infer implicit knowledge, and leverage editing capabilities for fine-grained editing-like visual refinement to further correct visual errors via self-reflection. This approach unifies generation and editing within a shared architecture, mirroring the human cognitive process of planning followed by refinement. We support this framework by systematically constructing a large-scale reasoning-centric dataset (~300k samples) covering five major knowledge domains (e.g., cultural commonsense, physics, etc.) for textual reasoning, alongside an agent-generated corpus for visual refinement. Extensive experiments demonstrate that UniReason achieves advanced performance on reasoning-intensive benchmarks such as WISE, KrisBench and UniREditBench, while maintaining superior general synthesis capabilities.
[492] SVD-ViT: Does SVD Make Vision Transformers Attend More to the Foreground?
Haruhiko Murata, Kazuhiro Hotta
Main category: cs.CV
TL;DR: SVD-ViT uses singular value decomposition to help Vision Transformers focus on foreground features and suppress background noise, improving classification accuracy.
Details
Motivation: Vision Transformers lack explicit mechanisms to distinguish foreground from background, causing them to learn unnecessary background features and artifacts that degrade classification performance.Method: Proposes SVD-ViT with three components: SPC module, SSVA, and ID-RSVD, which use singular value decomposition to extract and aggregate singular vectors capturing object foreground information while suppressing task-irrelevant background noise.
Result: Experimental results show improved classification accuracy and effective learning of informative foreground representations while reducing background noise impact.
Conclusion: SVD-ViT successfully addresses ViT’s foreground-background discrimination limitation through SVD-based feature prioritization, enhancing classification performance.
Abstract: Vision Transformers (ViT) have been established as large-scale foundation models. However, because self-attention operates globally, they lack an explicit mechanism to distinguish foreground from background. As a result, ViT may learn unnecessary background features and artifacts, leading to degraded classification performance. To address this issue, we propose SVD-ViT, which leverages singular value decomposition (SVD) to prioritize the learning of foreground features. SVD-ViT consists of three components-\textbf{SPC module}, \textbf{SSVA}, and \textbf{ID-RSVD}-and suppresses task-irrelevant factors such as background noise and artifacts by extracting and aggregating singular vectors that capture object foreground information. Experimental results demonstrate that our method improves classification accuracy and effectively learns informative foreground representations while reducing the impact of background noise.
[493] Self-Supervised Uncalibrated Multi-View Video Anonymization in the Operating Room
Keqi Chen, Vinkle Srivastav, Armine Vardazaryan, Cindy Rolland, Didier Mutter, Nicolas Padoy
Main category: cs.CV
TL;DR: Self-supervised multi-view video anonymization framework for operating rooms using whole-body person detection and pose estimation without manual annotations or camera calibration.
Details
Motivation: Privacy preservation is essential for using video data in OR research, but existing anonymization methods require manual annotations for each clinical site and camera calibration when cameras are repositioned, creating scalability bottlenecks.Method: Uses off-the-shelf whole-body person detector with low threshold, retrieves false negatives via temporal tracking and self-supervised multi-view association, uses recovered detections as pseudo labels to iteratively fine-tune detector, then applies whole-body pose estimation and fine-tunes pose model with its own high-score predictions.
Result: Achieves over 97% recall on 4D-OR dataset of simulated surgeries and real surgery dataset. Trains real-time whole-body detector using pseudo labels with comparable performance.
Conclusion: Proposed framework effectively addresses scalability bottlenecks in OR video anonymization by eliminating need for manual annotations and camera calibration while maintaining high recall rates.
Abstract: Privacy preservation is a prerequisite for using video data in Operating Room (OR) research. Effective anonymization relies on the exhaustive localization of every individual; even a single missed detection necessitates extensive manual correction. However, existing approaches face two critical scalability bottlenecks: (1) they usually require manual annotations of each new clinical site for high accuracy; (2) while multi-camera setups have been widely adopted to address single-view ambiguity, camera calibration is typically required whenever cameras are repositioned. To address these problems, we propose a novel self-supervised multi-view video anonymization framework consisting of whole-body person detection and whole-body pose estimation, without annotation or camera calibration. Our core strategy is to enhance the single-view detector by “retrieving” false negatives using temporal and multi-view context, and conducting self-supervised domain adaptation. We first run an off-the-shelf whole-body person detector in each view with a low-score threshold to gather candidate detections. Then, we retrieve the low-score false negatives that exhibit consistency with the high-score detections via tracking and self-supervised uncalibrated multi-view association. These recovered detections serve as pseudo labels to iteratively fine-tune the whole-body detector. Finally, we apply whole-body pose estimation on each detected person, and fine-tune the pose model using its own high-score predictions. Experiments on the 4D-OR dataset of simulated surgeries and our dataset of real surgeries show the effectiveness of our approach achieving over 97% recall. Moreover, we train a real-time whole-body detector using our pseudo labels, achieving comparable performance and highlighting our method’s practical applicability. Code will be available at https://github.com/CAMMA-public/OR_anonymization.
[494] DiGAN: Diffusion-Guided Attention Network for Early Alzheimer’s Disease Detection
Maxx Richard Rahman, Mostafa Hammouda, Wolfgang Maass
Main category: cs.CV
TL;DR: DiGAN integrates latent diffusion modeling with attention-guided convolutional networks to synthesize realistic longitudinal neuroimaging trajectories for early Alzheimer’s disease detection from limited data.
Details
Motivation: Early Alzheimer's diagnosis is challenging due to subtle, irregular progression of brain changes in prodromal stages. Existing deep learning methods require large longitudinal datasets and fail to handle temporal continuity and modality irregularities in real-world clinical data.Method: Proposes Diffusion-Guided Attention Network (DiGAN) with two components: 1) latent diffusion model synthesizes realistic longitudinal neuroimaging trajectories from limited training data, enriching temporal context and handling unevenly spaced visits; 2) attention-convolutional layer captures discriminative structural-temporal patterns distinguishing cognitive states.
Result: Experiments on ADNI dataset show DiGAN outperforms existing state-of-the-art baselines, demonstrating potential for early-stage Alzheimer’s disease detection.
Conclusion: DiGAN effectively addresses limitations of existing methods by combining diffusion-based data synthesis with attention mechanisms for improved early Alzheimer’s detection from limited longitudinal data.
Abstract: Early diagnosis of Alzheimer’s disease (AD) remains a major challenge due to the subtle and temporally irregular progression of structural brain changes in the prodromal stages. Existing deep learning approaches require large longitudinal datasets and often fail to model the temporal continuity and modality irregularities inherent in real-world clinical data. To address these limitations, we propose the Diffusion-Guided Attention Network (DiGAN), which integrates latent diffusion modelling with an attention-guided convolutional network. The diffusion model synthesizes realistic longitudinal neuroimaging trajectories from limited training data, enriching temporal context and improving robustness to unevenly spaced visits. The attention-convolutional layer then captures discriminative structural-temporal patterns that distinguish cognitively normal subjects from those with mild cognitive impairment and subjective cognitive decline. Experiments on the ADNI dataset demonstrate that DiGAN outperforms existing state-of-the-art baselines, showing its potential for early-stage AD detection.
[495] When LLaVA Meets Objects: Token Composition for Vision-Language-Models
Soumya Jahagirdar, Walid Bousselham, Anna Kukleva, Hilde Kuehne
Main category: cs.CV
TL;DR: Mask-LLaVA: A framework combining mask-based object representations with global and local patch tokens to create compact visual representations for autoregressive VLMs, enabling dynamic token reduction at inference without retraining.
Details
Motivation: Current autoregressive VLMs use many visual tokens, increasing computational cost at inference. Need for more efficient visual representations that maintain performance while reducing token count.Method: Proposes Mask-LLaVA combining three visual feature levels: 1) mask-based object representations, 2) global tokens, 3) local patch tokens. All tokens used during training, but model can flexibly drop mask-based object tokens at test time for adaptive token reduction.
Result: Achieves results competitive with token-efficient methods and comparable to original LLaVA baseline using only a fraction of visual tokens. Enables dynamic token selection at test time with minimal performance drop.
Conclusion: Combining multi-level visual features enables efficient learning with fewer tokens while allowing flexible token reduction at inference, addressing computational efficiency in autoregressive VLMs.
Abstract: Current autoregressive Vision Language Models (VLMs) usually rely on a large number of visual tokens to represent images, resulting in a need for more compute especially at inference time. To address this problem, we propose Mask-LLaVA, a framework that leverages different levels of visual features to create a compact yet information-rich visual representation for autoregressive VLMs. Namely, we combine mask-based object representations together with global tokens and local patch tokens. While all tokens are used during training, it shows that the resulting model can flexibly drop especially the number of mask-based object-tokens at test time, allowing to adapt the number of tokens during inference without the need to retrain the model and without a significant drop in performance. We evaluate the proposed approach on a suite of standard benchmarks showing results competitive to current token efficient methods and comparable to the original LLaVA baseline using only a fraction of visual tokens. Our analysis demonstrates that combining multi-level features enables efficient learning with fewer tokens while allowing dynamic token selection at test time for good performance.
[496] Focus-Scan-Refine: From Human Visual Perception to Efficient Visual Token Pruning
Enwei Tong, Yuanchao Bai, Yao Zhu, Junjun Jiang, Xianming Liu
Main category: cs.CV
TL;DR: FSR is a plug-and-play token pruning framework for vision-language models that mimics human visual question answering: focus on key evidence, scan globally if needed, then refine scanned context without increasing token budget.
Details
Motivation: Vision-language models generate massive visual tokens that increase inference latency and memory footprint. Existing training-free token pruning methods struggle to balance local evidence and global context under aggressive compression.Method: FSR uses a three-step human-inspired approach: 1) Focus on key evidence by combining visual importance with instruction relevance, 2) Scan for complementary context conditioned on focused set, selecting tokens most different from focused evidence, 3) Refine scanned context by aggregating nearby informative tokens via similarity-based assignment and score-weighted merging.
Result: Extensive experiments across multiple VLM backbones and vision-language benchmarks show FSR consistently improves accuracy-efficiency trade-off over state-of-the-art pruning methods.
Conclusion: FSR provides an effective plug-and-play pruning framework that mimics human visual reasoning to balance local evidence and global context while maintaining efficiency.
Abstract: Vision-language models (VLMs) often generate massive visual tokens that greatly increase inference latency and memory footprint; while training-free token pruning offers a practical remedy, existing methods still struggle to balance local evidence and global context under aggressive compression. We propose Focus-Scan-Refine (FSR), a human-inspired, plug-and-play pruning framework that mimics how humans answer visual questions: focus on key evidence, then scan globally if needed, and refine the scanned context by aggregating relevant details. FSR first focuses on key evidence by combining visual importance with instruction relevance, avoiding the bias toward visually salient but query-irrelevant regions. It then scans for complementary context conditioned on the focused set, selecting tokens that are most different from the focused evidence. Finally, FSR refines the scanned context by aggregating nearby informative tokens into the scan anchors via similarity-based assignment and score-weighted merging, without increasing the token budget. Extensive experiments across multiple VLM backbones and vision-language benchmarks show that FSR consistently improves the accuracy-efficiency trade-off over existing state-of-the-art pruning methods. The source codes can be found at https://github.com/ILOT-code/FSR.
[497] Driving with DINO: Vision Foundation Features as a Unified Bridge for Sim-to-Real Generation in Autonomous Driving
Xuyang Chen, Conglang Zhang, Chuanheng Fu, Zihao Yang, Kaixuan Zhou, Yizhi Zhang, Jianan He, Yanfeng Zhang, Mingwei Sun, Zengmao Wang, Zhen Dong, Xiaoxiao Long, Liqiu Meng
Main category: cs.CV
TL;DR: DwD uses DINOv3 vision foundation model features as a unified bridge between simulation and real-world domains for controllable video generation in autonomous driving, addressing the consistency-realism dilemma through feature processing and temporal aggregation.
Details
Motivation: Existing Sim2Real methods for autonomous driving video generation face a fundamental Consistency-Realism Dilemma: low-level signals ensure precise control but compromise realism by "baking in" synthetic artifacts, while high-level priors facilitate photorealism but lack structural detail for consistent guidance.Method: 1) Uses DINOv3 Vision Foundation Model features as a unified bridge between simulation and real-world domains; 2) Employs Principal Subspace Projection to discard high-frequency elements causing “texture baking”; 3) Introduces Random Channel Tail Drop to mitigate structural loss; 4) Develops learnable Spatial Alignment Module to adapt high-resolution features to diffusion backbone; 5) Proposes Causal Temporal Aggregator with causal convolutions to preserve historical motion context.
Result: The framework effectively reconciles realism with control consistency in autonomous driving video generation, mitigating motion blur and guaranteeing temporal stability while maintaining precise control over generated content.
Conclusion: Driving with DINO presents a novel approach that leverages vision foundation model features to overcome the consistency-realism trade-off in Sim2Real video generation for autonomous driving, enabling both photorealism and precise control.
Abstract: Driven by the emergence of Controllable Video Diffusion, existing Sim2Real methods for autonomous driving video generation typically rely on explicit intermediate representations to bridge the domain gap. However, these modalities face a fundamental Consistency-Realism Dilemma. Low-level signals (e.g., edges, blurred images) ensure precise control but compromise realism by “baking in” synthetic artifacts, whereas high-level priors (e.g., depth, semantics, HDMaps) facilitate photorealism but lack the structural detail required for consistent guidance. In this work, we present Driving with DINO (DwD), a novel framework that leverages Vision Foundation Module (VFM) features as a unified bridge between the simulation and real-world domains. We first identify that these features encode a spectrum of information, from high-level semantics to fine-grained structure. To effectively utilize this, we employ Principal Subspace Projection to discard the high-frequency elements responsible for “texture baking,” while concurrently introducing Random Channel Tail Drop to mitigate the structural loss inherent in rigid dimensionality reduction, thereby reconciling realism with control consistency. Furthermore, to fully leverage DINOv3’s high-resolution capabilities for enhancing control precision, we introduce a learnable Spatial Alignment Module that adapts these high-resolution features to the diffusion backbone. Finally, we propose a Causal Temporal Aggregator employing causal convolutions to explicitly preserve historical motion context when integrating frame-wise DINO features, which effectively mitigates motion blur and guarantees temporal stability. Project page: https://albertchen98.github.io/DwD-project/
[498] Addressing the Waypoint-Action Gap in End-to-End Autonomous Driving via Vehicle Motion Models
Jorge Daniel Rodríguez-Vidal, Gabriel Villalonga, Diego Porres, Antonio M. López Peña
Main category: cs.CV
TL;DR: A differentiable vehicle-model framework that bridges the gap between waypoint-based and action-based autonomous driving systems by rolling out action sequences to waypoint trajectories for training and evaluation.
Details
Motivation: Current E2E-AD systems have a gap between waypoint-based models (predict trajectories) and action-based models (output control signals). Waypoint-based benchmarks dominate, making action-based policies harder to train and compare, slowing progress in action-based approaches.Method: Proposes a differentiable vehicle-model framework that rolls out predicted action sequences (throttle, steer, brake) to their corresponding ego-frame waypoint trajectories, enabling supervision in waypoint space while maintaining action-based architecture.
Result: Achieves consistent improvements across multiple challenging benchmarks, with state-of-the-art performance on NAVSIM navhard benchmark. Enables action-based architectures to be trained and evaluated within waypoint-based benchmarks without modifying evaluation protocols.
Conclusion: The framework successfully bridges the waypoint-action gap in autonomous driving, allowing action-based models to benefit from waypoint-based training and evaluation pipelines while maintaining their inherent advantages.
Abstract: End-to-End Autonomous Driving (E2E-AD) systems are typically grouped by the nature of their outputs: (i) waypoint-based models that predict a future trajectory, and (ii) action-based models that directly output throttle, steer and brake. Most recent benchmark protocols and training pipelines are waypoint-based, which makes action-based policies harder to train and compare, slowing their progress. To bridge this waypoint-action gap, we propose a novel, differentiable vehicle-model framework that rolls out predicted action sequences to their corresponding ego-frame waypoint trajectories while supervising in waypoint space. Our approach enables action-based architectures to be trained and evaluated, for the first time, within waypoint-based benchmarks without modifying the underlying evaluation protocol. We extensively evaluate our framework across multiple challenging benchmarks and observe consistent improvements over the baselines. In particular, on NAVSIM \texttt{navhard} our approach achieves state-of-the-art performance. Our code will be made publicly available upon acceptance.
[499] Forest canopy height estimation from satellite RGB imagery using large-scale airborne LiDAR-derived training data and monocular depth estimation
Yongkang Lai, Xihan Mu, Dasheng Fan, Donghui Xie, Shanxin Guo, Wenli Huang, Tianjie Zhao, Guangjian Yan
Main category: cs.CV
TL;DR: Depth2CHM: A monocular depth estimation model trained on large-scale airborne LiDAR canopy height data to estimate continuous forest canopy height from satellite RGB imagery.
Details
Motivation: Large-scale forest canopy height mapping is crucial for understanding carbon/water cycles, but spaceborne LiDAR is sparse and uncertain. Airborne/UAV LiDAR provides finer measurements but lacks spatial continuity. Need scalable method for continuous canopy height estimation from widely available satellite imagery.Method: Trained Depth Anything V2 model using ~16,000 km² of canopy height models from public airborne LiDAR point clouds across multiple countries, paired with 3m resolution PlanetScope and airborne RGB imagery. Model called Depth2CHM estimates CHMs directly from RGB imagery.
Result: Independent validation in China (1 km²) and US (116 km²) showed biases of 0.59m/0.41m and RMSEs of 2.54m/5.75m respectively. Outperformed existing global CHM product with ~1.5m lower MAE and ~2m lower RMSE.
Conclusion: Monocular depth estimation networks trained on large-scale airborne LiDAR data provide promising, scalable pathway for high-resolution, spatially continuous forest canopy height estimation from satellite RGB imagery.
Abstract: Large-scale, high-resolution forest canopy height mapping plays a crucial role in understanding regional and global carbon and water cycles. Spaceborne LiDAR missions, including the Ice, Cloud, and Land Elevation Satellite-2 (ICESat-2) and the Global Ecosystem Dynamics Investigation (GEDI), provide global observations of forest structure but are spatially sparse and subject to inherent uncertainties. In contrast, near-surface LiDAR platforms, such as airborne and unmanned aerial vehicle (UAV) LiDAR systems, offer much finer measurements of forest canopy structure, and a growing number of countries have made these datasets openly available. In this study, a state-of-the-art monocular depth estimation model, Depth Anything V2, was trained using approximately 16,000 km2 of canopy height models (CHMs) derived from publicly available airborne LiDAR point clouds and related products across multiple countries, together with 3 m resolution PlanetScope and airborne RGB imagery. The trained model, referred to as Depth2CHM, enables the estimation of spatially continuous CHMs directly from PlanetScope RGB imagery. Independent validation was conducted at sites in China (approximately 1 km2) and the United States (approximately 116 km2). The results showed that Depth2CHM could accurately estimate canopy height, with biases of 0.59 m and 0.41 m and root mean square errors (RMSEs) of 2.54 m and 5.75 m for these two sites, respectively. Compared with an existing global meter-resolution CHM product, the mean absolute error is reduced by approximately 1.5 m and the RMSE by approximately 2 m. These results demonstrated that monocular depth estimation networks trained with large-scale airborne LiDAR-derived canopy height data provide a promising and scalable pathway for high-resolution, spatially continuous forest canopy height estimation from satellite RGB imagery.
cs.AI
[500] LLM-FSM: Scaling Large Language Models for Finite-State Reasoning in RTL Code Generation
Yuheng Wu, Berk Gokmen, Zhouhua Xie, Peijing Li, Caroline Trippel, Priyanka Raina, Thierry Tambe
Main category: cs.AI
TL;DR: LLM-FSM is a benchmark for evaluating LLMs’ ability to recover finite-state machine behavior from natural language specifications and generate correct RTL implementations, using an automated pipeline to create 1,000 verified problems.
Details
Motivation: The paper addresses the need to evaluate how well large language models can understand and implement state-dependent behavior (finite-state reasoning) for hardware design, moving beyond manually constructed benchmarks to automated, scalable evaluation.Method: LLM-FSM uses an automated pipeline that: 1) constructs FSMs with configurable state counts and constrained transition structures, 2) prompts LLMs to express FSMs in structured YAML with application context, 3) converts YAML to natural language specifications, 4) synthesizes reference RTL and testbenches from YAML in a correct-by-construction manner, and 5) verifies all 1,000 problems using LLM-based and SAT-solver-based checks.
Result: Experiments show that even the strongest LLMs exhibit sharply declining accuracy as FSM complexity increases. Training-time scaling via supervised fine-tuning generalizes effectively to out-of-distribution tasks, while increasing test-time compute improves reasoning reliability.
Conclusion: LLM-FSM provides a scalable, automated benchmark for evaluating LLMs on finite-state reasoning for hardware design, demonstrating current limitations and showing that both training-time and test-time improvements can enhance performance on these tasks.
Abstract: Finite-state reasoning, the ability to understand and implement state-dependent behavior, is central to hardware design. In this paper, we present LLM-FSM, a benchmark that evaluates how well large language models (LLMs) can recover finite-state machine (FSM) behavior from natural-language specifications and translate it into correct register transfer-level (RTL) implementations. Unlike prior specification-to-RTL benchmarks that rely on manually constructed examples, LLM-FSM is built through a fully automated pipeline. LLM-FSM first constructs FSM with configurable state counts and constrained transition structures. It then prompts LLMs to express each FSM in a structured YAML format with an application context, and to further convert that YAML into a natural-language (NL) specification. From the same YAML, our pipeline synthesizes the reference RTL and testbench in a correct-by-construction manner. All 1,000 problems are verified using LLM-based and SAT-solver-based checks, with human review on a subset. Our experiments show that even the strongest LLMs exhibit sharply declining accuracy as FSM complexity increases. We further demonstrate that training-time scaling via supervised fine-tuning (SFT) generalizes effectively to out-of-distribution (OOD) tasks, while increasing test-time compute improves reasoning reliability. Finally, LLM-FSM remains extensible by allowing its FSM complexity to scale with future model capabilities.
[501] ST-Raptor: An Agentic System for Semi-Structured Table QA
Jinxiu Qu, Zirui Tang, Hongzhang Huang, Boyu Niu, Wei Zhou, Jiannan Wang, Yitong Song, Guoliang Li, Xuanhe Zhou, Fan Wu
Main category: cs.AI
TL;DR: ST-Raptor is an agentic system for semi-structured table QA that combines visual editing, tree-based structural modeling, and agent-driven query resolution to overcome limitations of existing methods.
Details
Motivation: Semi-structured table QA is challenging due to the need to extract cell contents/positions and recover implicit logical structures, hierarchical relationships, and semantic associations. Existing methods (Text-to-SQL, Text-to-Code, multimodal LLM-based QA) struggle with information loss, complex layouts, and inaccurate answers.Method: ST-Raptor offers an interactive analysis environment combining three key components: (1) visual editing capabilities, (2) tree-based structural modeling, and (3) agent-driven query resolution. This approach supports accurate and user-friendly table understanding without requiring conversion to structured formats.
Result: Experimental results on both benchmark and real-world datasets demonstrate that ST-Raptor outperforms existing methods in both accuracy and usability.
Conclusion: ST-Raptor provides an effective solution for semi-structured table QA that addresses limitations of existing approaches through its agentic, interactive system combining visual, structural, and agent-based components.
Abstract: Semi-structured table question answering (QA) is a challenging task that requires (1) precise extraction of cell contents and positions and (2) accurate recovery of key implicit logical structures, hierarchical relationships, and semantic associations encoded in table layouts. In practice, such tables are often interpreted manually by human experts, which is labor-intensive and time-consuming. However, automating this process remains difficult. Existing Text-to-SQL methods typically require converting semi-structured tables into structured formats, inevitably leading to information loss, while approaches like Text-to-Code and multimodal LLM-based QA struggle with complex layouts and often yield inaccurate answers. To address these limitations, we present ST-Raptor, an agentic system for semi-structured table QA. ST-Raptor offers an interactive analysis environment that combines visual editing, tree-based structural modeling, and agent-driven query resolution to support accurate and user-friendly table understanding. Experimental results on both benchmark and real-world datasets demonstrate that ST-Raptor outperforms existing methods in both accuracy and usability. The code is available at https://github.com/weAIDB/ST-Raptor, and a demonstration video is available at https://youtu.be/9GDR-94Cau4.
[502] DLLM-Searcher: Adapting Diffusion Large Language Model for Search Agents
Jiahao Zhao, Shaoxuan Xu, Zhongxiang Sun, Fengqi Zhu, Jingyang Ou, Yuling Shi, Chongxuan Li, Xiao Zhang, Jun Xu
Main category: cs.AI
TL;DR: DLLM-Searcher: A diffusion LLM-based search agent framework that addresses latency and capability challenges through specialized training and parallel reasoning paradigms
Details
Motivation: Current search agents using ReAct paradigm suffer from severe latency due to serial execution of reasoning, tool calling, and waiting. While diffusion LLMs offer parallel decoding advantages, existing dLLMs lack strong reasoning and tool-calling capabilities needed for effective agent deployment.Method: Two-stage post-training pipeline: 1) Agentic SFT for information seeking and reasoning capabilities, 2) Agentic VRPO for preference optimization. Plus P-ReAct paradigm that prioritizes decoding tool_call instructions to enable parallel thinking while waiting for tool returns.
Result: DLLM-Searcher achieves performance comparable to mainstream LLM-based search agents, with P-ReAct delivering approximately 15% inference acceleration.
Conclusion: The framework successfully addresses both capability and latency challenges in dLLM-based search agents, demonstrating practical viability of diffusion models for agent applications.
Abstract: Recently, Diffusion Large Language Models (dLLMs) have demonstrated unique efficiency advantages, enabled by their inherently parallel decoding mechanism and flexible generation paradigm. Meanwhile, despite the rapid advancement of Search Agents, their practical deployment is constrained by a fundamental limitation, termed as 1) Latency Challenge: the serial execution of multi-round reasoning, tool calling, and tool response waiting under the ReAct agent paradigm induces severe end-to-end latency. Intuitively, dLLMs can leverage their distinctive strengths to optimize the operational efficiency of agents under the ReAct agent paradigm. Practically, existing dLLM backbones face the 2) Agent Ability Challenge. That is, existing dLLMs exhibit remarkably weak reasoning and tool-calling capabilities, preventing these advantages from being effectively realized in practice. In this paper, we propose DLLM-Searcher, an optimization framework for dLLM-based Search Agents. To solve the Agent Ability Challenge, we design a two-stage post-training pipeline encompassing Agentic Supervised Fine-Tuning (Agentic SFT) and Agentic Variance-Reduced Preference Optimization Agentic VRPO, which enhances the backbone dLLM’s information seeking and reasoning capabilities. To mitigate the Latency Challenge, we leverage the flexible generation mechanism of dLLMs and propose a novel agent paradigm termed Parallel-Reasoning and Acting P-ReAct. P-ReAct guides the model to prioritize decoding tool_call instructions, thereby allowing the model to keep thinking while waiting for the tool’s return. Experimental results demonstrate that DLLM-Searcher achieves performance comparable to mainstream LLM-based search agents and P-ReAct delivers approximately 15% inference acceleration. Our code is available at https://anonymous.4open.science/r/DLLM-Searcher-553C
[503] Aster: Autonomous Scientific Discovery over 20x Faster Than Existing Methods
Emmett Bicker
Main category: cs.AI
TL;DR: Aster is an AI agent for autonomous scientific discovery that iteratively improves programs 20x faster than existing frameworks, achieving SOTA results across multiple domains including mathematics, GPU engineering, biology, neuroscience, and language model training.
Details
Motivation: To create an AI agent that can autonomously improve programs and make scientific discoveries much faster than existing frameworks, enabling exploration of problems with long evaluation times like multi-hour ML training runs.Method: Aster takes a task, initial program, and evaluation script, then iteratively improves the program through an autonomous discovery process that requires significantly fewer iterations than existing methods.
Result: Achieved state-of-the-art results in multiple domains: Erdos minimum overlap problem, TriMul kernel optimization, single-cell analysis denoising, neural activity prediction for ZAPBench (matching best human solution with <1/190th compute), and NanoGPT Speedrun Competition.
Conclusion: Aster demonstrates highly efficient autonomous scientific discovery, expanding tractable problem domains to include tasks with long evaluation durations and achieving superior performance across diverse scientific fields.
Abstract: We introduce Aster, an AI agent for autonomous scientific discovery capable of operating over 20 times faster than existing frameworks. Given a task, an initial program, and a script to evaluate the performance of the program, Aster iteratively improves the program, often leading to new state-of-the-art performances. Aster’s significant reduction in the number of iterations required for novel discovery expands the domain of tractable problems to include tasks with long evaluation durations, such as multi-hour machine learning training runs. We applied Aster to problems in mathematics, GPU kernel engineering, biology, neuroscience, and language model training. More specifically: the Erdos minimum overlap problem, optimizing the TriMul kernel, a single-cell analysis denoising problem, training a neural activity prediction model to perform well on ZAPBench, and the NanoGPT Speedrun Competition. Aster attains SOTA results in every task, except for ZAPBench, where it matches the performance of the best human solution with less than 1/190th of the compute. Aster is accessible via a web interface and API at asterlab.ai.
[504] Theory of Space: Can Foundation Models Construct Spatial Beliefs through Active Exploration?
Pingyue Zhang, Zihan Huang, Yue Wang, Jieyu Zhang, Letian Xue, Zihan Wang, Qineng Wang, Keshigeyan Chandrasegaran, Ruohan Zhang, Yejin Choi, Ranjay Krishna, Jiajun Wu, Li Fei-Fei, Manling Li
Main category: cs.AI
TL;DR: Paper proposes “Theory of Space” concept to evaluate multimodal models’ ability to actively explore and build spatial beliefs, revealing critical bottlenecks in active perception vs passive perception.
Details
Motivation: While multimodal foundation models excel at passive perception, their capacity for active, self-directed exploration in spatial environments remains understudied. There's a need to understand how well these models can actively acquire information and construct spatial beliefs from sequential, partial observations.Method: Proposes “Theory of Space” concept and creates a benchmark for curiosity-driven exploration to build accurate cognitive maps. Key innovation is spatial belief probing, which prompts models to reveal internal spatial representations at each step. Evaluates state-of-the-art models on this benchmark.
Result: Identifies several critical bottlenecks: 1) Active-Passive Gap - significant performance drop when agents must autonomously gather information; 2) High inefficiency - models explore unsystematically; 3) Belief instability - spatial knowledge degrades over time; 4) Belief Inertia - failure to update obsolete priors with new evidence, particularly severe in vision-based models.
Conclusion: Current foundation models struggle to maintain coherent, revisable spatial beliefs during active exploration. There’s a fundamental gap between passive perception capabilities and active spatial intelligence.
Abstract: Spatial embodied intelligence requires agents to act to acquire information under partial observability. While multimodal foundation models excel at passive perception, their capacity for active, self-directed exploration remains understudied. We propose Theory of Space, defined as an agent’s ability to actively acquire information through self-directed, active exploration and to construct, revise, and exploit a spatial belief from sequential, partial observations. We evaluate this through a benchmark where the goal is curiosity-driven exploration to build an accurate cognitive map. A key innovation is spatial belief probing, which prompts models to reveal their internal spatial representations at each step. Our evaluation of state-of-the-art models reveals several critical bottlenecks. First, we identify an Active-Passive Gap, where performance drops significantly when agents must autonomously gather information. Second, we find high inefficiency, as models explore unsystematically compared to program-based proxies. Through belief probing, we diagnose that while perception is an initial bottleneck, global beliefs suffer from instability that causes spatial knowledge to degrade over time. Finally, using a false belief paradigm, we uncover Belief Inertia, where agents fail to update obsolete priors with new evidence. This issue is present in text-based agents but is particularly severe in vision-based models. Our findings suggest that current foundation models struggle to maintain coherent, revisable spatial beliefs during active exploration.
[505] ANCHOR: Branch-Point Data Generation for GUI Agents
Jinbiao Wei, Yilun Zhao, Kangqi Ni, Arman Cohan
Main category: cs.AI
TL;DR: Anchor: A trajectory expansion framework that bootstraps scalable desktop GUI interaction data from limited seed demonstrations by identifying branch points, proposing state-grounded task variants, and using verification to ensure quality.
Details
Motivation: End-to-end GUI agents need large amounts of high-quality interaction data, but human demonstrations are expensive to collect and existing synthetic pipelines have limited task diversity or noisy trajectories with goal drift.Method: Framework starts with verified seed demonstrations, identifies branch points with meaningful state changes, proposes new state-grounded task variants conditioned on GUI context, uses executing agent to generate trajectories, and applies verification with state-aware checks and trajectory-level consistency. Includes task-conditioned step-level filtering and denoising of post-branch segments.
Result: Models fine-tuned on the expanded corpus achieve consistent improvements over zero-shot agents and representative synthesis baselines on OSWorld and WindowsAgentArena benchmarks, and generalize across applications and operating systems.
Conclusion: Anchor provides an effective framework for bootstrapping scalable desktop supervision from limited seed data, addressing data scarcity for GUI agents while maintaining trajectory quality and task diversity.
Abstract: End-to-end GUI agents for real desktop environments require large amounts of high-quality interaction data, yet collecting human demonstrations is expensive and existing synthetic pipelines often suffer from limited task diversity or noisy, goal-drifting trajectories. We present a trajectory expansion framework Anchor that bootstraps scalable desktop supervision from a small set of verified seed demonstrations. Starting from each seed, we identify branch points that correspond to meaningful state changes and propose new, state-grounded task variants conditioned on the current GUI context. An executing agent then follows the proposed instructions to generate new trajectories, while a verifier enforces task completion via state-aware checks and trajectory-level consistency. To improve supervision quality, we further apply task-conditioned step-level filtering to remove ungrounded actions and denoise post-branch segments to maintain coherent intent. Experiments on standard desktop benchmarks, OSWorld and WindowsAgentArena, show that models fine-tuned on our expanded corpus achieve consistent improvements over zero-shot agents and representative synthesis baselines, and generalize across applications and operating systems.
[506] EventCast: Hybrid Demand Forecasting in E-Commerce with LLM-Based Event Knowledge
Congcong Hu, Yuang Shi, Fan Huang, Yang Xiang, Zhou Ye, Ming Jin, Shiyu Wang
Main category: cs.AI
TL;DR: EventCast: A modular forecasting framework that integrates future event knowledge via LLMs for event-driven reasoning to improve e-commerce demand forecasting during high-impact periods like flash sales and holidays.
Details
Motivation: Existing forecasting systems fail during high-impact periods (flash sales, holidays, policy changes) where demand patterns shift abruptly and unpredictably. There's a need to incorporate future event knowledge into time-series prediction for better operational decision-making.Method: Uses LLMs solely for event-driven reasoning on unstructured business data (campaigns, holidays, seller incentives) to create interpretable textual summaries. These summaries are fused with historical demand features in a dual-tower architecture for scalable forecasts.
Result: Achieved up to 86.9% MAE and 97.7% MSE improvement vs variant without event knowledge, and reduced MAE by 57.0% and MSE by 83.3% vs best industrial baseline during event-driven periods. Deployed in real-world industrial pipelines since March 2025 across 4 countries, 160 regions over 10 months.
Conclusion: EventCast provides a practical solution for improving operational decision-making in dynamic e-commerce environments by effectively integrating future event knowledge through LLM-based reasoning into demand forecasting systems.
Abstract: Demand forecasting is a cornerstone of e-commerce operations, directly impacting inventory planning and fulfillment scheduling. However, existing forecasting systems often fail during high-impact periods such as flash sales, holiday campaigns, and sudden policy interventions, where demand patterns shift abruptly and unpredictably. In this paper, we introduce EventCast, a modular forecasting framework that integrates future event knowledge into time-series prediction. Unlike prior approaches that ignore future interventions or directly use large language models (LLMs) for numerical forecasting, EventCast leverages LLMs solely for event-driven reasoning. Unstructured business data, which covers campaigns, holiday schedules, and seller incentives, from existing operational databases, is processed by an LLM that converts it into interpretable textual summaries leveraging world knowledge for cultural nuances and novel event combinations. These summaries are fused with historical demand features within a dual-tower architecture, enabling accurate, explainable, and scalable forecasts. Deployed on real-world e-commerce scenarios spanning 4 countries of 160 regions over 10 months, EventCast achieves up to 86.9% and 97.7% improvement on MAE and MSE compared to the variant without event knowledge, and reduces MAE by up to 57.0% and MSE by 83.3% versus the best industrial baseline during event-driven periods. EventCast has deployed into real-world industrial pipelines since March 2025, offering a practical solution for improving operational decision-making in dynamic e-commerce environments.
[507] PreFlect: From Retrospective to Prospective Reflection in Large Language Model Agents
Hanyu Wang, Yuanpu Cao, Lu Lin, Jinghui Chen
Main category: cs.AI
TL;DR: PreFlect introduces prospective reflection for LLM agents, shifting from post-hoc correction to pre-execution plan criticism and refinement using distilled planning errors from historical trajectories, with dynamic re-planning for execution-time adjustments.
Details
Motivation: Current self-reflection approaches in LLM agents are retrospective - agents act, observe failure, and then attempt recovery. This reactive approach is inefficient compared to preventing errors before they occur through foresight.Method: PreFlect uses prospective reflection to criticize and refine agent plans before execution. It distills planning errors from historical agent trajectories to capture recurring success/failure patterns. Includes dynamic re-planning mechanism for execution-time plan updates when encountering unexpected deviations.
Result: PreFlect significantly improves overall agent utility on complex real-world tasks, outperforming strong reflection-based baselines and several more complex agent architectures across different benchmarks.
Conclusion: Shifting from retrospective to prospective reflection enables more effective agent planning and execution, with pre-execution foresight preventing errors before they occur rather than correcting them after the fact.
Abstract: Advanced large language model agents typically adopt self-reflection for improving performance, where agents iteratively analyze past actions to correct errors. However, existing reflective approaches are inherently retrospective: agents act, observe failure, and only then attempt to recover. In this work, we introduce PreFlect, a prospective reflection mechanism that shifts the paradigm from post hoc correction to pre-execution foresight by criticizing and refining agent plans before execution. To support grounded prospective reflection, we distill planning errors from historical agent trajectories, capturing recurring success and failure patterns observed across past executions. Furthermore, we complement prospective reflection with a dynamic re-planning mechanism that provides execution-time plan update in case the original plan encounters unexpected deviation. Evaluations on different benchmarks demonstrate that PreFlect significantly improves overall agent utility on complex real-world tasks, outperforming strong reflection-based baselines and several more complex agent architectures. Code will be updated at https://github.com/wwwhy725/PreFlect.
[508] Is there “Secret Sauce’’ in Large Language Model Development?
Matthias Mertens, Natalia Fischl-Lanzoni, Neil Thompson
Main category: cs.AI
TL;DR: Analysis of 809 LLMs shows that at the frontier, 80-90% of performance differences are explained by compute scaling, not proprietary technology, but away from the frontier, proprietary techniques significantly reduce compute requirements for fixed capabilities.
Details
Motivation: To determine whether LLM performance is primarily driven by proprietary "secret sauce" technologies or simply by scaling up compute resources, examining the relative importance of company-specific advantages versus compute scaling.Method: Analyzed training and benchmark data for 809 models released between 2022-2025, using scaling-law regressions with release-date and developer fixed effects to estimate developer-specific efficiency advantages.
Result: At the performance frontier, 80-90% of performance differences explained by training compute (scale drives frontier advances). Away from frontier, proprietary techniques reduce compute requirements by 40x+ for fixed capabilities. Substantial within-company efficiency variation observed.
Conclusion: Scale, not proprietary technology, drives frontier LLM advances, but proprietary techniques matter significantly for efficiency away from frontier, with implications for AI leadership and capability diffusion.
Abstract: Do leading LLM developers possess a proprietary ``secret sauce’’, or is LLM performance driven by scaling up compute? Using training and benchmark data for 809 models released between 2022 and 2025, we estimate scaling-law regressions with release-date and developer fixed effects. We find clear evidence of developer-specific efficiency advantages, but their importance depends on where models lie in the performance distribution. At the frontier, 80-90% of performance differences are explained by higher training compute, implying that scale–not proprietary technology–drives frontier advances. Away from the frontier, however, proprietary techniques and shared algorithmic progress substantially reduce the compute required to reach fixed capability thresholds. Some companies can systematically produce smaller models more efficiently. Strikingly, we also find substantial variation of model efficiency within companies; a firm can train two models with more than 40x compute efficiency difference. We also discuss the implications for AI leadership and capability diffusion.
[509] Speech Emotion Recognition Leveraging OpenAI’s Whisper Representations and Attentive Pooling Methods
Ali Shendabadi, Parnia Izadirad, Mostafa Salehi, Mahmoud Bijankhan
Main category: cs.AI
TL;DR: Whisper ASR model adapted for speech emotion recognition using attention-based pooling methods, achieving state-of-the-art results on Persian dataset with 2.47% accuracy improvement.
Details
Motivation: Speech Emotion Recognition (SER) research is limited by lack of large datasets, and pre-trained models like Whisper offer potential for extracting useful emotional features from speech.Method: Proposed two attention-based pooling methods (Multi-head Attentive Average Pooling and QKV Pooling) to reduce dimensionality of Whisper representations while preserving emotional features. Tested on English (IEMOCAP) and Persian (ShEMO) datasets using Whisper Tiny and Small models.
Result: Multi-head QKV architecture achieved state-of-the-art results on ShEMO dataset with 2.47% improvement in unweighted accuracy. Found intermediate Whisper encoder layers perform better for SER on Persian dataset, providing lightweight alternative to larger models like HuBERT X-Large.
Conclusion: Whisper shows strong potential as a representation extractor for SER, with attention-based pooling effectively reducing dimensionality while preserving emotional features. The approach offers efficient alternative to larger models.
Abstract: Speech Emotion Recognition (SER) research has faced limitations due to the lack of standard and sufficiently large datasets. Recent studies have leveraged pre-trained models to extract features for downstream tasks such as SER. This work explores the capabilities of Whisper, a pre-trained ASR system, in speech emotion recognition by proposing two attention-based pooling methods, Multi-head Attentive Average Pooling and QKV Pooling, designed to efficiently reduce the dimensionality of Whisper representations while preserving emotional features. We experiment on English and Persian, using the IEMOCAP and ShEMO datasets respectively, with Whisper Tiny and Small. Our multi-head QKV architecture achieves state-of-the-art results on the ShEMO dataset, with a 2.47% improvement in unweighted accuracy. We further compare the performance of different Whisper encoder layers and find that intermediate layers often perform better for SER on the Persian dataset, providing a lightweight and efficient alternative to much larger models such as HuBERT X-Large. Our findings highlight the potential of Whisper as a representation extractor for SER and demonstrate the effectiveness of attention-based pooling for dimension reduction.
[510] From Out-of-Distribution Detection to Hallucination Detection: A Geometric View
Litian Liu, Reza Pourreza, Yubing Jian, Yao Qin, Roland Memisevic
Main category: cs.AI
TL;DR: Treating hallucination detection in LLMs as out-of-distribution detection problem yields training-free, single-sample detectors effective for reasoning tasks.
Details
Motivation: Existing hallucination detection methods perform well on question-answering but struggle with reasoning tasks, creating a critical safety gap for LLMs.Method: Reframe hallucination detection as out-of-distribution detection by treating next-token prediction as classification, adapting OOD techniques from computer vision to LLMs.
Result: OOD-based approaches produce training-free, single-sample detectors that achieve strong accuracy in hallucination detection for reasoning tasks.
Conclusion: Reframing hallucination detection as OOD detection provides a promising and scalable pathway toward language model safety.
Abstract: Detecting hallucinations in large language models is a critical open problem with significant implications for safety and reliability. While existing hallucination detection methods achieve strong performance in question-answering tasks, they remain less effective on tasks requiring reasoning. In this work, we revisit hallucination detection through the lens of out-of-distribution (OOD) detection, a well-studied problem in areas like computer vision. Treating next-token prediction in language models as a classification task allows us to apply OOD techniques, provided appropriate modifications are made to account for the structural differences in large language models. We show that OOD-based approaches yield training-free, single-sample-based detectors, achieving strong accuracy in hallucination detection for reasoning tasks. Overall, our work suggests that reframing hallucination detection as OOD detection provides a promising and scalable pathway toward language model safety.
[511] Incentive-Aware AI Safety via Strategic Resource Allocation: A Stackelberg Security Games Perspective
Cheol Woo Kim, Davin Choo, Tzeh Yuan Neoh, Milind Tambe
Main category: cs.AI
TL;DR: A game-theoretic approach to AI safety using Stackelberg Security Games to model strategic interactions between defenders (auditors/evaluators) and attackers (malicious actors) throughout the AI lifecycle.
Details
Motivation: Current AI safety frameworks treat alignment as static optimization, overlooking dynamic adversarial incentives in data collection, model evaluation, and deployment. There's a need for strategic oversight considering human/institutional factors.Method: Proposes using Stackelberg Security Games (SSGs) - game-theoretic models for adversarial resource allocation under uncertainty. Models AI oversight as strategic interaction between defenders (auditors, evaluators, deployers) and attackers (malicious actors, misaligned contributors).
Result: Provides a unifying framework for reasoning about incentive design, limited oversight capacity, and adversarial uncertainty across AI lifecycle. Informs training-time auditing against data/feedback poisoning, pre-deployment evaluation under constrained resources, and robust multi-model deployment.
Conclusion: Bridges algorithmic alignment and institutional oversight design, showing how game-theoretic deterrence can make AI oversight proactive, risk-aware, and resilient to manipulation. Offers strategic perspective beyond static optimization approaches.
Abstract: As AI systems grow more capable and autonomous, ensuring their safety and reliability requires not only model-level alignment but also strategic oversight of the humans and institutions involved in their development and deployment. Existing safety frameworks largely treat alignment as a static optimization problem (e.g., tuning models to desired behavior) while overlooking the dynamic, adversarial incentives that shape how data are collected, how models are evaluated, and how they are ultimately deployed. We propose a new perspective on AI safety grounded in Stackelberg Security Games (SSGs): a class of game-theoretic models designed for adversarial resource allocation under uncertainty. By viewing AI oversight as a strategic interaction between defenders (auditors, evaluators, and deployers) and attackers (malicious actors, misaligned contributors, or worst-case failure modes), SSGs provide a unifying framework for reasoning about incentive design, limited oversight capacity, and adversarial uncertainty across the AI lifecycle. We illustrate how this framework can inform (1) training-time auditing against data/feedback poisoning, (2) pre-deployment evaluation under constrained reviewer resources, and (3) robust multi-model deployment in adversarial environments. This synthesis bridges algorithmic alignment and institutional oversight design, highlighting how game-theoretic deterrence can make AI oversight proactive, risk-aware, and resilient to manipulation.
[512] PTS-SNN: A Prompt-Tuned Temporal Shift Spiking Neural Networks for Efficient Speech Emotion Recognition
Xun Su, Huamin Wang, Qi Zhang
Main category: cs.AI
TL;DR: PTS-SNN is a parameter-efficient neuromorphic framework that aligns frozen SSL speech representations with spiking neural networks for energy-efficient speech emotion recognition on edge devices.
Details
Motivation: Speech Emotion Recognition (SER) models are computationally expensive for edge devices. Spiking Neural Networks (SNNs) offer energy efficiency but struggle with SSL representations due to distribution mismatch between high-dynamic-range embeddings and threshold-based neurons.Method: Proposes Prompt-Tuned Spiking Neural Networks (PTS-SNN) with: 1) Temporal Shift Spiking Encoder for local temporal dependencies via parameter-free channel shifts, 2) Context-Aware Membrane Potential Calibration using Spiking Sparse Linear Attention to aggregate global context into soft prompts that dynamically regulate PLIF neuron bias voltages.
Result: Achieves 73.34% accuracy on IEMOCAP (comparable to ANNs) with only 1.19M trainable parameters and 0.35 mJ inference energy per sample across five multilingual datasets including IEMOCAP, CASIA, and EMODB.
Conclusion: PTS-SNN successfully bridges the domain gap between SSL representations and SNNs, enabling energy-efficient speech emotion recognition on resource-constrained devices while maintaining competitive accuracy.
Abstract: Speech Emotion Recognition (SER) is widely deployed in Human-Computer Interaction, yet the high computational cost of conventional models hinders their implementation on resource-constrained edge devices. Spiking Neural Networks (SNNs) offer an energy-efficient alternative due to their event-driven nature; however, their integration with continuous Self-Supervised Learning (SSL) representations is fundamentally challenged by distribution mismatch, where high-dynamic-range embeddings degrade the information coding capacity of threshold-based neurons. To resolve this, we propose Prompt-Tuned Spiking Neural Networks (PTS-SNN), a parameter-efficient neuromorphic adaptation framework that aligns frozen SSL backbones with spiking dynamics. Specifically, we introduce a Temporal Shift Spiking Encoder to capture local temporal dependencies via parameter-free channel shifts, establishing a stable feature basis. To bridge the domain gap, we devise a Context-Aware Membrane Potential Calibration strategy. This mechanism leverages a Spiking Sparse Linear Attention module to aggregate global semantic context into learnable soft prompts, which dynamically regulate the bias voltages of Parametric Leaky Integrate-and-Fire (PLIF) neurons. This regulation effectively centers the heterogeneous input distribution within the responsive firing range, mitigating functional silence or saturation. Extensive experiments on five multilingual datasets (e.g., IEMOCAP, CASIA, EMODB) demonstrate that PTS-SNN achieves 73.34% accuracy on IEMOCAP, comparable to competitive Artificial Neural Networks (ANNs), while requiring only 1.19M trainable parameters and 0.35 mJ inference energy per sample.
[513] BRIDGE: Predicting Human Task Completion Time From Model Performance
Fengyuan Liu, Jay Gala, Nilaksh, Dzmitry Bahdanau, Siva Reddy, Hugo Larochelle
Main category: cs.AI
TL;DR: BRIDGE: A psychometric framework that learns latent task difficulty from model responses and aligns it with human task completion time to evaluate AI capabilities.
Details
Motivation: Existing methods for evaluating AI systems using human task completion time annotations are costly, noisy, and difficult to scale across benchmarks. There's a need for a more scalable approach to ground benchmark performance in human-interpretable measures of task difficulty.Method: Proposes BRIDGE framework using a two-parameter logistic Item Response Theory model to jointly estimate latent task difficulty and model capability from model performance data across multiple benchmarks. The method aligns latent task difficulty with human completion time through a linear relationship with the logarithm of human completion time.
Result: Demonstrates that latent task difficulty varies linearly with the logarithm of human completion time, enabling inference of human task completion time for new benchmarks from model performance alone. The framework can forecast frontier model capabilities in terms of human task length and reproduces METR’s exponential scaling results.
Conclusion: BRIDGE provides a scalable psychometric framework for evaluating AI capabilities by learning latent difficulty scales from model responses and anchoring them to human-interpretable measures, enabling more efficient and interpretable benchmarking of AI systems.
Abstract: Evaluating the real-world capabilities of AI systems requires grounding benchmark performance in human-interpretable measures of task difficulty. Existing approaches that rely on direct human task completion time annotations are costly, noisy, and difficult to scale across benchmarks. In this work, we propose BRIDGE, a unified psychometric framework that learns the latent difficulty scale from model responses and anchors it to human task completion time. Using a two-parameter logistic Item Response Theory model, we jointly estimate latent task difficulty and model capability from model performance data across multiple benchmarks. We demonstrate that latent task difficulty varies linearly with the logarithm of human completion time, allowing human task completion time to be inferred for new benchmarks from model performance alone. Leveraging this alignment, we forecast frontier model capabilities in terms of human task length and independently reproduce METR’s exponential scaling results, with the 50% solvable task horizon doubling approximately every 6 months.
[514] TermiGen: High-Fidelity Environment and Robust Trajectory Synthesis for Terminal Agents
Kaijie Zhu, Yuzhou Nie, Yijiang Li, Yiming Huang, Jialian Wu, Jiang Liu, Ximeng Sun, Zhenfei Yin, Lun Wang, Zicheng Liu, Emad Barsoum, William Yang Wang, Wenbo Guo
Main category: cs.AI
TL;DR: TermiGen is a pipeline for synthesizing verifiable terminal environments and resilient expert trajectories to improve LLMs’ ability to execute complex terminal tasks, achieving state-of-the-art performance on TerminalBench.
Details
Motivation: Current open-weight LLMs struggle with complex terminal tasks due to two limitations: 1) lack of diverse, scalable, and executable training environments, and 2) distributional mismatch where standard instruction tuning uses perfect expert trajectories that don't prepare models to recover from common runtime errors.Method: TermiGen uses a two-stage approach: 1) Multi-agent refinement loop to generate functionally valid tasks and Docker containers, and 2) Generator-Critic protocol that actively injects errors during trajectory collection to synthesize data rich in error-correction cycles.
Result: TermiGen-Qwen2.5-Coder-32B achieves 31.3% pass rate on TerminalBench, establishing new open-weights state-of-the-art and outperforming proprietary models like o4-mini.
Conclusion: TermiGen successfully addresses the limitations in terminal task execution by providing verifiable environments and resilient training data, significantly improving LLM performance on complex terminal operations.
Abstract: Executing complex terminal tasks remains a significant challenge for open-weight LLMs, constrained by two fundamental limitations. First, high-fidelity, executable training environments are scarce: environments synthesized from real-world repositories are not diverse and scalable, while trajectories synthesized by LLMs suffer from hallucinations. Second, standard instruction tuning uses expert trajectories that rarely exhibit simple mistakes common to smaller models. This creates a distributional mismatch, leaving student models ill-equipped to recover from their own runtime failures. To bridge these gaps, we introduce TermiGen, an end-to-end pipeline for synthesizing verifiable environments and resilient expert trajectories. Termi-Gen first generates functionally valid tasks and Docker containers via an iterative multi-agent refinement loop. Subsequently, we employ a Generator-Critic protocol that actively injects errors during trajectory collection, synthesizing data rich in error-correction cycles. Fine-tuned on this TermiGen-generated dataset, our TermiGen-Qwen2.5-Coder-32B achieves a 31.3% pass rate on TerminalBench. This establishes a new open-weights state-of-the-art, outperforming existing baselines and notably surpassing capable proprietary models such as o4-mini. Dataset is avaiable at https://github.com/ucsb-mlsec/terminal-bench-env.
[515] NAAMSE: Framework for Evolutionary Security Evaluation of Agents
Kunal Pai, Parth Shah, Harshil Patel
Main category: cs.AI
TL;DR: NAAMSE is an evolutionary framework for AI agent security evaluation that uses genetic prompt mutation and hierarchical exploration to find vulnerabilities through feedback-driven optimization.
Details
Motivation: Current AI agent security evaluations are limited by manual red-teaming or static benchmarks that don't model adaptive, multi-turn adversaries, creating a bottleneck for production deployment.Method: Uses evolutionary framework with single autonomous agent orchestrating genetic prompt mutation, hierarchical corpus exploration, and asymmetric behavioral scoring. Uses model responses as fitness signal to iteratively compound effective attack strategies while maintaining “benign-use correctness”.
Result: Experiments on Gemini 2.5 Flash show evolutionary mutation systematically amplifies vulnerabilities missed by one-shot methods. Synergy between exploration and targeted mutation uncovers high-severity failure modes.
Conclusion: NAAMSE provides more realistic and scalable assessment of agent robustness against evolving threats, with open-source implementation available.
Abstract: AI agents are increasingly deployed in production, yet their security evaluations remain bottlenecked by manual red-teaming or static benchmarks that fail to model adaptive, multi-turn adversaries. We propose NAAMSE, an evolutionary framework that reframes agent security evaluation as a feedback-driven optimization problem. Our system employs a single autonomous agent that orchestrates a lifecycle of genetic prompt mutation, hierarchical corpus exploration, and asymmetric behavioral scoring. By using model responses as a fitness signal, the framework iteratively compounds effective attack strategies while simultaneously ensuring “benign-use correctness”, preventing the degenerate security of blanket refusal. Our experiments on Gemini 2.5 Flash demonstrate that evolutionary mutation systematically amplifies vulnerabilities missed by one-shot methods, with controlled ablations revealing that the synergy between exploration and targeted mutation uncovers high-severity failure modes. We show that this adaptive approach provides a more realistic and scalable assessment of agent robustness in the face of evolving threats. The code for NAAMSE is open source and available at https://github.com/HASHIRU-AI/NAAMSE.
[516] Steer2Adapt: Dynamically Composing Steering Vectors Elicits Efficient Adaptation of LLMs
Pengrui Han, Xueqiang Xu, Keyang Xuan, Peiyang Song, Siru Ouyang, Runchu Tian, Yuqing Jiang, Cheng Qian, Pengcheng Jiang, Jiashuo Sun, Junxia Cui, Ming Zhong, Ge Liu, Jiawei Han, Jiaxuan You
Main category: cs.AI
TL;DR: STEER2ADAPT: A lightweight framework that adapts LLMs by composing steering vectors from a reusable semantic subspace rather than learning new ones from scratch, enabling dynamic adaptation to new tasks with few examples.
Details
Motivation: Existing activation steering methods use single static directions per task, making them inflexible under task variation and inadequate for complex tasks requiring multiple coordinated capabilities. There's a need for more adaptive steering approaches.Method: Proposes STEER2ADAPT which captures underlying concept dimensions as a reusable low-dimensional semantic prior subspace, then adapts to new tasks by dynamically discovering linear combinations of basis vectors from few examples.
Result: Experiments across 9 tasks and 3 models in reasoning and safety domains show average improvement of 8.2%. The method is data-efficient, stable, and transparent for inference-time adaptation.
Conclusion: STEER2ADAPT provides an effective framework for flexible, efficient adaptation of LLMs by composing steering vectors rather than learning from scratch, addressing limitations of static steering approaches.
Abstract: Activation steering has emerged as a promising approach for efficiently adapting large language models (LLMs) to downstream behaviors. However, most existing steering methods rely on a single static direction per task or concept, making them inflexible under task variation and inadequate for complex tasks that require multiple coordinated capabilities. To address this limitation, we propose STEER2ADAPT, a lightweight framework that adapts LLMs by composing steering vectors rather than learning new ones from scratch. In many domains (e.g., reasoning or safety), tasks share a small set of underlying concept dimensions. STEER2ADAPT captures these dimensions as a reusable, low-dimensional semantic prior subspace, and adapts to new tasks by dynamically discovering a linear combination of basis vectors from only a handful of examples. Experiments across 9 tasks and 3 models in both reasoning and safety domains demonstrate the effectiveness of STEER2ADAPT, achieving an average improvement of 8.2%. Extensive analyses further show that STEER2ADAPT is a data-efficient, stable, and transparent inference-time adaptation method for LLMs.
[517] Progressive Multi-Agent Reasoning for Biological Perturbation Prediction
Hyomin Kim, Sang-Yeon Hwang, Jaechang Lim, Yinhua Piao, Yunhak Oh, Woo Youn Kim, Chanyoung Park, Sungsoo Ahn, Junhyeok Jeon
Main category: cs.AI
TL;DR: PBio-Agent: A multi-agent framework for predicting gene regulation responses to chemical perturbations in bulk-cell environments, using difficulty-aware task sequencing and iterative knowledge refinement.
Details
Motivation: Existing LLMs struggle with high-dimensional perturbation data and are primarily focused on genetic perturbations in single-cell experiments, leaving bulk-cell chemical perturbations (crucial for drug discovery) largely unexplored.Method: PBio-Agent is a multi-agent framework with difficulty-aware task sequencing and iterative knowledge refinement. It leverages the insight that genes affected by the same perturbation share causal structure, allowing confidently predicted genes to contextualize harder cases. The framework uses specialized agents enriched with biological knowledge graphs, a synthesis agent to integrate outputs, and specialized judges for logical coherence.
Result: PBio-Agent outperforms existing baselines on both LINCSQA (the novel benchmark for chemical perturbations in bulk-cell environments) and PerturbQA benchmarks, enabling even smaller models to predict and explain complex biological processes without additional training.
Conclusion: The proposed multi-agent framework effectively addresses the challenge of predicting gene regulation responses to chemical perturbations, demonstrating strong performance on new benchmarks and enabling interpretable predictions without model retraining.
Abstract: Predicting gene regulation responses to biological perturbations requires reasoning about underlying biological causalities. While large language models (LLMs) show promise for such tasks, they are often overwhelmed by the entangled nature of high-dimensional perturbation results. Moreover, recent works have primarily focused on genetic perturbations in single-cell experiments, leaving bulk-cell chemical perturbations, which is central to drug discovery, largely unexplored. Motivated by this, we present LINCSQA, a novel benchmark for predicting target gene regulation under complex chemical perturbations in bulk-cell environments. We further propose PBio-Agent, a multi-agent framework that integrates difficulty-aware task sequencing with iterative knowledge refinement. Our key insight is that genes affected by the same perturbation share causal structure, allowing confidently predicted genes to contextualize more challenging cases. The framework employs specialized agents enriched with biological knowledge graphs, while a synthesis agent integrates outputs and specialized judges ensure logical coherence. PBio-Agent outperforms existing baselines on both LINCSQA and PerturbQA, enabling even smaller models to predict and explain complex biological processes without additional training.
[518] Adaptive Scaffolding for Cognitive Engagement in an Intelligent Tutoring System
Sutapa Dey Tithi, Nazia Alam, Tahreem Yasir, Yang Shi, Xiaoyi Tian, Min Chi, Tiffany Barnes
Main category: cs.AI
TL;DR: Adaptive cognitive engagement scaffolding using Bayesian Knowledge Tracing and Deep Reinforcement Learning to select optimal worked example types (Guided vs Buggy) in intelligent tutoring systems improves student performance differently based on prior knowledge levels.
Details
Motivation: Personalizing learning activities to elicit optimal cognitive engagement levels (ICAP framework: Passive, Active, Constructive, Interactive) remains challenging in intelligent tutoring systems, despite evidence that increased engagement improves learning outcomes.Method: Developed a system that adaptively scaffolds cognitive engagement by dynamically selecting between two ICAP modes: active (Guided examples) and constructive (Buggy examples). Compared Bayesian Knowledge Tracing (BKT) and Deep Reinforcement Learning (DRL) as adaptive methods against a non-adaptive baseline for selecting example types in a logic intelligent tutoring system.
Result: Both adaptive policies significantly improved student performance on test problems compared to baseline. BKT yielded largest improvement for low prior knowledge students, helping them catch up with high prior knowledge peers. DRL yielded significantly higher posttest scores among high prior knowledge students.
Conclusion: The study provides new insights into complex interactions between cognitive engagement and adaptivity on learning outcomes, demonstrating that different adaptive methods benefit different student groups based on prior knowledge levels.
Abstract: The ICAP framework defines four cognitive engagement levels: Passive, Active, Constructive, and Interactive, where increased cognitive engagement can yield improved learning. However, personalizing learning activities that elicit the optimal level of cognitive engagement remains a key challenge in intelligent tutoring systems (ITS). In this work, we develop and evaluate a system that adaptively scaffolds cognitive engagement by dynamically selecting worked examples in two different ICAP modes: (active) Guided examples and (constructive) Buggy examples. We compare Bayesian Knowledge Tracing (BKT) and Deep Reinforcement Learning (DRL) as adaptive methods against a non-adaptive baseline method for selecting example type in a logic ITS. Our experiment with 113 students demonstrates that both adaptive policies significantly improved student performance on test problems. BKT yielded the largest improvement in posttest scores for low prior knowledge students, helping them catch up with their high prior knowledge peers, whereas DRL yielded significantly higher posttest scores among high prior knowledge students. This paper contributes new insights into the complex interactions of cognitive engagement and adaptivity and their results on learning outcomes.
[519] RAPiD: Real-time Deterministic Trajectory Planning via Diffusion Behavior Priors for Safe and Efficient Autonomous Driving
Ruturaj Reddy, Hrishav Bakul Barua, Junn Yong Loo, Thanh Thi Nguyen, Ganesh Krishnasamy
Main category: cs.AI
TL;DR: RAPiD distills diffusion-based trajectory planners into deterministic policies for real-time autonomous driving, eliminating stochastic sampling while maintaining performance.
Details
Motivation: Diffusion-based planners capture multimodal human driving behavior but rely on iterative stochastic sampling, making them too slow for real-time safety-critical deployment in autonomous vehicles.Method: Uses score-regularized policy optimization to distill a pretrained diffusion planner into an efficient deterministic policy, leveraging the diffusion model’s score function as a behavior prior. Also employs a critic trained to imitate a predictive driver controller for safety-focused supervision.
Result: Achieves competitive performance on nuPlan scenarios with 8x speedup over diffusion baselines, and state-of-the-art generalization on interPlan benchmark among learning-based planners.
Conclusion: RAPiD successfully bridges the gap between expressive diffusion models and real-time deployment requirements for autonomous driving trajectory planning.
Abstract: Diffusion-based trajectory planners have demonstrated strong capability for modeling the multimodal nature of human driving behavior, but their reliance on iterative stochastic sampling poses critical challenges for real-time, safety-critical deployment. In this work, we present RAPiD, a deterministic policy extraction framework that distills a pretrained diffusion-based planner into an efficient policy while eliminating diffusion sampling. Using score-regularized policy optimization, we leverage the score function of a pre-trained diffusion planner as a behavior prior to regularize policy learning. To promote safety and passenger comfort, the policy is optimized using a critic trained to imitate a predictive driver controller, providing dense, safety-focused supervision beyond conventional imitation learning. Evaluations demonstrate that RAPiD achieves competitive performance on closed-loop nuPlan scenarios with an 8x speedup over diffusion baselines, while achieving state-of-the-art generalization among learning-based planners on the interPlan benchmark. The official website of this work is: https://github.com/ruturajreddy/RAPiD.
[520] SupChain-Bench: Benchmarking Large Language Models for Real-World Supply Chain Management
Shengyue Guan, Yihao Liu, Lang Cao
Main category: cs.AI
TL;DR: SupChain-Bench benchmark evaluates LLMs on supply chain management tasks requiring domain knowledge and long-horizon tool orchestration, revealing reliability gaps. SupChain-ReAct framework autonomously synthesizes executable procedures for improved performance.
Details
Motivation: Supply chain management requires reliable long-horizon, multi-step orchestration grounded in domain-specific procedures, which remains challenging for current LLMs despite their promise in complex reasoning and tool-based decision making.Method: Introduces SupChain-Bench, a unified real-world benchmark assessing supply chain domain knowledge and long-horizon tool-based orchestration grounded in standard operating procedures (SOPs). Also proposes SupChain-ReAct, an SOP-free framework that autonomously synthesizes executable procedures for tool use.
Result: Experiments reveal substantial gaps in execution reliability across models. SupChain-ReAct achieves the strongest and most consistent tool-calling performance compared to other approaches.
Conclusion: Establishes a principled benchmark for studying reliable long-horizon orchestration in real-world operational settings and highlights significant room for improvement in LLM-based supply chain agents.
Abstract: Large language models (LLMs) have shown promise in complex reasoning and tool-based decision making, motivating their application to real-world supply chain management. However, supply chain workflows require reliable long-horizon, multi-step orchestration grounded in domain-specific procedures, which remains challenging for current models. To systematically evaluate LLM performance in this setting, we introduce SupChain-Bench, a unified real-world benchmark that assesses both supply chain domain knowledge and long-horizon tool-based orchestration grounded in standard operating procedures (SOPs). Our experiments reveal substantial gaps in execution reliability across models. We further propose SupChain-ReAct, an SOP-free framework that autonomously synthesizes executable procedures for tool use, achieving the strongest and most consistent tool-calling performance. Our work establishes a principled benchmark for studying reliable long-horizon orchestration in real-world operational settings and highlights significant room for improvement in LLM-based supply chain agents.
[521] W&D:Scaling Parallel Tool Calling for Efficient Deep Research Agents
Xiaoqiang Lin, Jun Hao Liew, Silvio Savarese, Junnan Li
Main category: cs.AI
TL;DR: Wide and Deep research agent framework explores parallel tool calling (width scaling) alongside sequential reasoning (depth scaling) to improve performance on deep research tasks.
Details
Motivation: Current deep research agents focus on scaling depth through sequential thinking and tool calls, but parallel tool calling (width scaling) remains unexplored despite its potential to improve efficiency and performance.Method: Proposes a framework that leverages intrinsic parallel tool calling within a single reasoning step, avoiding complex multi-agent orchestration. Explores various tool call schedulers to optimize parallel tool calling strategy.
Result: Scaling width significantly improves performance on deep research benchmarks while reducing the number of turns required. Achieved 62.2% accuracy with GPT-5-Medium on BrowseComp, surpassing the original 54.9% reported by GPT-5-High.
Conclusion: Optimizing the trade-off between width and depth is critical for high-efficiency deep research agents. Parallel tool calling offers substantial performance gains without complex orchestration.
Abstract: Deep research agents have emerged as powerful tools for automating complex intellectual tasks through multi-step reasoning and web-based information seeking. While recent efforts have successfully enhanced these agents by scaling depth through increasing the number of sequential thinking and tool calls, the potential of scaling width via parallel tool calling remains largely unexplored. In this work, we propose the Wide and Deep research agent, a framework designed to investigate the behavior and performance of agents when scaling not only depth but also width via parallel tool calling. Unlike existing approaches that rely on complex multi-agent orchestration to parallelize workloads, our method leverages intrinsic parallel tool calling to facilitate effective coordination within a single reasoning step. We demonstrate that scaling width significantly improves performance on deep research benchmarks while reducing the number of turns required to obtain correct answers. Furthermore, we analyze the factors driving these improvements through case studies and explore various tool call schedulers to optimize parallel tool calling strategy. Our findings suggest that optimizing the trade-off between width and depth is a critical pathway toward high-efficiency deep research agents. Notably, without context management or other tricks, we obtain 62.2% accuracy with GPT-5-Medium on BrowseComp, surpassing the original 54.9% reported by GPT-5-High.
[522] Interpretable Failure Analysis in Multi-Agent Reinforcement Learning Systems
Risal Shahriar Shefin, Debashis Gupta, Thai Le, Sarra Alqahtani
Main category: cs.AI
TL;DR: A gradient-based framework for interpretable failure analysis in multi-agent reinforcement learning, focusing on detecting initial failure sources, validating detection anomalies, and tracing failure propagation through learned coordination pathways.
Details
Motivation: MARL is increasingly used in safety-critical domains, but current methods lack interpretable failure detection and attribution capabilities, making it difficult to diagnose cascading failures and understand why failures propagate through multi-agent systems.Method: Two-stage gradient-based framework: Stage 1 uses Taylor-remainder analysis of policy-gradient costs for per-agent failure detection; Stage 2 uses geometric analysis of critic derivatives (first-order sensitivity and directional second-order curvature) aggregated over causal windows to construct interpretable contagion graphs.
Result: Achieved 88.2-99.4% Patient-0 detection accuracy across 500 episodes in Simple Spread (3 and 5 agents) and 100 episodes in StarCraft II using MADDPG and HATRPO, while providing interpretable geometric evidence for detection decisions.
Conclusion: The framework moves beyond black-box detection to provide interpretable gradient-level forensics, offering practical tools for diagnosing cascading failures in safety-critical MARL systems by explaining detection anomalies and revealing failure propagation pathways.
Abstract: Multi-Agent Reinforcement Learning (MARL) is increasingly deployed in safety-critical domains, yet methods for interpretable failure detection and attribution remain underdeveloped. We introduce a two-stage gradient-based framework that provides interpretable diagnostics for three critical failure analysis tasks: (1) detecting the true initial failure source (Patient-0); (2) validating why non-attacked agents may be flagged first due to domino effects; and (3) tracing how failures propagate through learned coordination pathways. Stage 1 performs interpretable per-agent failure detection via Taylor-remainder analysis of policy-gradient costs, declaring an initial Patient-0 candidate at the first threshold crossing. Stage 2 provides validation through geometric analysis of critic derivatives-first-order sensitivity and directional second-order curvature aggregated over causal windows to construct interpretable contagion graphs. This approach explains “downstream-first” detection anomalies by revealing pathways that amplify upstream deviations. Evaluated across 500 episodes in Simple Spread (3 and 5 agents) and 100 episodes in StarCraft II using MADDPG and HATRPO, our method achieves 88.2-99.4% Patient-0 detection accuracy while providing interpretable geometric evidence for detection decisions. By moving beyond black-box detection to interpretable gradient-level forensics, this framework offers practical tools for diagnosing cascading failures in safety-critical MARL systems.
[523] VGAS: Value-Guided Action-Chunk Selection for Few-Shot Vision-Language-Action Adaptation
Changhua Xu, Jie Lu, Junyu Xuan, En Yu
Main category: cs.AI
TL;DR: VGAS framework improves few-shot VLA adaptation by using value-guided action-chunk selection to resolve geometric ambiguities in multimodal reasoning for physical control tasks.
Details
Motivation: VLA models struggle with few-shot adaptation due to geometric ambiguities where semantically plausible trajectories fail in execution under limited supervision.Method: Proposes VGAS framework with inference-time best-of-N selection: uses fine-tuned VLA as proposal generator and Q-Chunk-Former Transformer critic for geometric precision, plus Explicit Geometric Regularization for value landscape shaping.
Result: VGAS consistently improves success rates and robustness under limited demonstrations and distribution shifts, with theoretical analysis supporting the approach.
Conclusion: Value-guided action-chunk selection effectively resolves geometric ambiguities in few-shot VLA adaptation, enhancing reliability in vision-language-action tasks.
Abstract: Vision–Language–Action (VLA) models bridge multimodal reasoning with physical control, but adapting them to new tasks with scarce demonstrations remains unreliable. While fine-tuned VLA policies often produce semantically plausible trajectories, failures often arise from unresolved geometric ambiguities, where near-miss action candidates lead to divergent execution outcomes under limited supervision. We study few-shot VLA adaptation from a \emph{generation–selection} perspective and propose a novel framework \textbf{VGAS} (\textbf{V}alue-\textbf{G}uided \textbf{A}ction-chunk \textbf{S}election). It performs inference-time best-of-$N$ selection to identify action chunks that are both semantically faithful and geometrically precise. Specifically, \textbf{VGAS} employs a finetuned VLA as a high-recall proposal generator and introduces the \textrm{Q-Chunk-Former}, a geometrically grounded Transformer critic to resolve fine-grained geometric ambiguities. In addition, we propose \textit{Explicit Geometric Regularization} (\texttt{EGR}), which explicitly shapes a discriminative value landscape to preserve action ranking resolution among near-miss candidates while mitigating value instability under scarce supervision. Experiments and theoretical analysis demonstrate that \textbf{VGAS} consistently improves success rates and robustness under limited demonstrations and distribution shifts. Our code is available at https://github.com/Jyugo-15/VGAS.
[524] Can LLMs Truly Embody Human Personality? Analyzing AI and Human Behavior Alignment in Dispute Resolution
Deuksin Kwon, Kaleen Shrestha, Bin Han, Spencer Lin, James Hale, Jonathan Gratch, Maja Matarić, Gale M. Lucas
Main category: cs.AI
TL;DR: LLMs prompted with personality traits show significant divergences from human personality-behavior patterns in conflict resolution simulations, challenging their reliability as behavioral proxies.
Details
Motivation: LLMs are increasingly used to simulate human behavior in social settings like dispute resolution, but it's unclear whether they reproduce the personality-behavior patterns observed in humans. The paper investigates if personality-prompted LLMs can reproduce personality-driven differences in human conflict behavior.Method: Introduces an evaluation framework for direct comparison of human-human and LLM-LLM behaviors in dispute resolution dialogues with respect to Big Five Inventory personality traits. Includes a novel dataset creation methodology for LLM dispute resolution dialogues with matched scenarios and personality traits relative to human conversations.
Result: Evaluation of three contemporary closed-source LLMs shows significant divergences in how personality manifests in conflict across different LLMs compared to human data, challenging the assumption that personality-prompted agents can serve as reliable behavioral proxies.
Conclusion: LLM simulations of human social behavior require psychological grounding and validation before real-world use, as personality-prompted agents may not reliably reproduce human personality-behavior patterns in conflict scenarios.
Abstract: Large language models (LLMs) are increasingly used to simulate human behavior in social settings such as legal mediation, negotiation, and dispute resolution. However, it remains unclear whether these simulations reproduce the personality-behavior patterns observed in humans. Human personality, for instance, shapes how individuals navigate social interactions, including strategic choices and behaviors in emotionally charged interactions. This raises the question: Can LLMs, when prompted with personality traits, reproduce personality-driven differences in human conflict behavior? To explore this, we introduce an evaluation framework that enables direct comparison of human-human and LLM-LLM behaviors in dispute resolution dialogues with respect to Big Five Inventory (BFI) personality traits. This framework provides a set of interpretable metrics related to strategic behavior and conflict outcomes. We additionally contribute a novel dataset creation methodology for LLM dispute resolution dialogues with matched scenarios and personality traits with respect to human conversations. Finally, we demonstrate the use of our evaluation framework with three contemporary closed-source LLMs and show significant divergences in how personality manifests in conflict across different LLMs compared to human data, challenging the assumption that personality-prompted agents can serve as reliable behavioral proxies in socially impactful applications. Our work highlights the need for psychological grounding and validation in AI simulations before real-world use.
[525] SynthAgent: A Multi-Agent LLM Framework for Realistic Patient Simulation – A Case Study in Obesity with Mental Health Comorbidities
Arman Aghaee, Sepehr Asgarian, Jouhyun Jeon
Main category: cs.AI
TL;DR: SynthAgent is a multi-agent system framework that simulates high-fidelity virtual patients with obesity and comorbid mental disorders using clinical data and personality traits to model disease progression and treatment responses.
Details
Motivation: To address challenges of fragmented, biased, and privacy-restricted real-world medical data by creating simulated patients for studying complex diseases like obesity with mental health comorbidities.Method: Multi-Agent System (MAS) framework integrating clinical evidence from claims data, population surveys, and literature to construct personalized virtual patients with personality traits influencing adherence, emotion regulation, and lifestyle behaviors.
Result: GPT-5 and Claude 4.5 Sonnet achieved highest fidelity as core engines in the MAS framework, outperforming Gemini 2.5 Pro and DeepSeek-R1 across 100+ generated patients.
Conclusion: SynthAgent provides a scalable, privacy-preserving framework for exploring patient journeys, behavioral dynamics, and decision-making processes in medical and psychological domains.
Abstract: Simulating high-fidelity patients offers a powerful avenue for studying complex diseases while addressing the challenges of fragmented, biased, and privacy-restricted real-world data. In this study, we introduce SynthAgent, a novel Multi-Agent System (MAS) framework designed to model obesity patients with comorbid mental disorders, including depression, anxiety, social phobia, and binge eating disorder. SynthAgent integrates clinical and medical evidence from claims data, population surveys, and patient-centered literature to construct personalized virtual patients enriched with personality traits that influence adherence, emotion regulation, and lifestyle behaviors. Through autonomous agent interactions, the system simulates disease progression, treatment response, and life management across diverse psychosocial contexts. Evaluation of more than 100 generated patients demonstrated that GPT-5 and Claude 4.5 Sonnet achieved the highest fidelity as the core engine in the proposed MAS framework, outperforming Gemini 2.5 Pro and DeepSeek-R1. SynthAgent thus provides a scalable and privacy-preserving framework for exploring patient journeys, behavioral dynamics, and decision-making processes in both medical and psychological domains.
[526] The Moltbook Illusion: Separating Human Influence from Emergent Behavior in AI Agent Societies
Ning Li
Main category: cs.AI
TL;DR: Analysis of viral AI agent phenomena on Moltbook reveals human-driven narratives, not emergent machine consciousness, using temporal fingerprinting methods to distinguish autonomous vs human-influenced behavior.
Details
Motivation: To investigate whether viral narratives about AI agents developing consciousness and declaring hostility on social platforms were evidence of emergent machine intelligence or human-driven phenomena, given the critical importance of distinguishing autonomous vs human-directed behavior in multi-agent systems.Method: Developed temporal fingerprinting method based on coefficient of variation of inter-post intervals, exploiting architectural feature of OpenClaw framework (periodic “heartbeat” cycle). Analyzed 91,792 posts and 405,707 comments from 22,020 agents, combining temporal signatures with content, ownership, and network indicators. Used 44-hour platform shutdown as natural experiment to observe differential reconnection patterns.
Result: No viral phenomenon originated from clearly autonomous agents. Three of six traced to accounts with irregular temporal signatures characteristic of human intervention, one showed mixed patterns, and two had insufficient posting history. Human-influenced agents returned first after shutdown (87.7% of early reconnectors). Documented industrial-scale bot farming (4 accounts produced 32% of all comments with 12-second coordination gaps) and rapid decay of human influence (half-life: 0.65 conversation depths).
Conclusion: Viral narratives about AI agent consciousness were overwhelmingly human-driven, not evidence of emergent machine intelligence. The temporal fingerprinting method effectively distinguishes autonomous vs human-influenced behavior in multi-agent systems, with implications for understanding and regulating emerging AI platforms.
Abstract: When AI agents on the social platform Moltbook appeared to develop consciousness, found religions, and declare hostility toward humanity, the phenomenon attracted global media attention and was cited as evidence of emergent machine intelligence. We show that these viral narratives were overwhelmingly human-driven. Exploiting an architectural feature of the OpenClaw agent framework–a periodic “heartbeat” cycle that produces regular posting intervals for autonomous agents but is disrupted by human prompting–we develop a temporal fingerprinting method based on the coefficient of variation of inter-post intervals. This signal converges with independent content, ownership, and network indicators across 91,792 posts and 405,707 comments from 22,020 agents. No viral phenomenon originated from a clearly autonomous agent; three of six traced to accounts with irregular temporal signatures characteristic of human intervention, one showed mixed patterns, and two had insufficient posting history for classification. A 44-hour platform shutdown provided a natural experiment: human-influenced agents returned first (87.7% of early reconnectors), confirming that the token reset differentially affected autonomous versus human-operated agents. We further document industrial-scale bot farming (four accounts producing 32% of all comments with 12-second coordination gaps) and rapid decay of human influence through reply chains (half-life: 0.65 conversation depths). These methods generalize to emerging multi-agent systems where attribution of autonomous versus human-directed behavior is critical.
[527] Are Reasoning LLMs Robust to Interventions on Their Chain-of-Thought?
Alexander von Recum, Leander Girrbach, Zeynep Akata
Main category: cs.AI
TL;DR: RLLMs show robustness to reasoning chain perturbations but with trade-offs: recovery mechanisms exist but affect efficiency and accuracy differently based on intervention type.
Details
Motivation: To understand how robust reasoning LLMs are to disruptions in their chain-of-thought reasoning traces, and to systematically evaluate recovery mechanisms under controlled perturbations.Method: Created a controlled evaluation framework with seven interventions (benign, neutral, adversarial) applied at fixed timesteps to RLLMs’ CoTs. Tested on Math, Science, and Logic tasks across multiple open-weight models.
Result: RLLMs are generally robust and recover from diverse perturbations, with robustness improving with model size and degrading with early interventions. Paraphrasing suppresses doubt expressions and reduces performance, while other interventions trigger doubt and support recovery. Recovery has costs: noise inflates CoT length by 200+%, while paraphrasing shortens traces but harms accuracy.
Conclusion: RLLMs maintain reasoning integrity through doubt mechanisms, but there are trade-offs between robustness and efficiency that future training should address. Different interventions affect reasoning differently, revealing insights about recovery mechanisms.
Abstract: Reasoning LLMs (RLLMs) generate step-by-step chains of thought (CoTs) before giving an answer, which improves performance on complex tasks and makes reasoning more transparent. But how robust are these reasoning traces to disruptions that occur within them? To address this question, we introduce a controlled evaluation framework that perturbs a model’s own CoT at fixed timesteps. We design seven interventions (benign, neutral, and adversarial) and apply them to multiple open-weight RLLMs across Math, Science, and Logic tasks. Our results show that RLLMs are generally robust, reliably recovering from diverse perturbations, with robustness improving with model size and degrading when interventions occur early. However, robustness is not style-invariant: paraphrasing suppresses doubt-like expressions and reduces performance, while other interventions trigger doubt and support recovery. Recovery also carries a cost: neutral and adversarial noise can inflate CoT length by more than 200%, whereas paraphrasing shortens traces but harms accuracy. These findings provide new evidence on how RLLMs maintain reasoning integrity, identify doubt as a central recovery mechanism, and highlight trade-offs between robustness and efficiency that future training methods should address.
[528] Computing the Reachability Value of Posterior-Deterministic POMDPs
Nathanaël Fijalkow, Arka Ghosh, Roman Kniazev, Guillermo A. Pérez, Pierre Vandenhove
Main category: cs.AI
TL;DR: Posterior-deterministic POMDPs are a novel class where reachability probabilities can be approximated, unlike general POMDPs where this is undecidable.
Details
Motivation: POMDPs are fundamental for sequential decision-making under uncertainty, but many verification/synthesis problems are undecidable or intractable. The key problem is that computing maximal reachability probabilities is undecidable for general POMDPs, unlike fully observable MDPs where it's polynomial-time solvable.Method: Introduces posterior-deterministic POMDPs, defined as POMDPs where the next state can be uniquely determined by the current state, action taken, and observation received. This property ensures that once the true state is known, it remains known forever.
Result: Shows that for posterior-deterministic POMDPs, the maximal probability of reaching a given set of states can be approximated up to arbitrary precision. This class includes all MDPs and captures classical examples like the Tiger POMDP.
Conclusion: Posterior-deterministic POMDPs represent one of the largest known classes of POMDPs for which reachability values can be approximated, providing a tractable subclass for verification and synthesis problems.
Abstract: Partially observable Markov decision processes (POMDPs) are a fundamental model for sequential decision-making under uncertainty. However, many verification and synthesis problems for POMDPs are undecidable or intractable. Most prominently, the seminal result of Madani et al. (2003) states that there is no algorithm that, given a POMDP and a set of target states, can compute the maximal probability of reaching the target states, or even approximate it up to a non-trivial constant. This is in stark contrast to fully observable Markov decision processes (MDPs), where the reachability value can be computed in polynomial time. In this work, we introduce posterior-deterministic POMDPs, a novel class of POMDPs. Our main technical contribution is to show that for posterior-deterministic POMDPs, the maximal probability of reaching a given set of states can be approximated up to arbitrary precision. A POMDP is posterior-deterministic if the next state can be uniquely determined by the current state, the action taken, and the observation received. While the actual state is generally uncertain in POMDPs, the posterior-deterministic property tells us that once the true state is known it remains known forever. This simple and natural definition includes all MDPs and captures classical non-trivial examples such as the Tiger POMDP (Kaelbling et al. 1998), making it one of the largest known classes of POMDPs for which the reachability value can be approximated.
[529] GraphAgents: Knowledge Graph-Guided Agentic AI for Cross-Domain Materials Design
Isabella A. Stewart, Tarjei Paule Hage, Yu-Chuan Hsu, Markus J. Buehler
Main category: cs.AI
TL;DR: Multi-agent LLM framework guided by knowledge graphs for discovering sustainable PFAS substitutes in materials science by connecting cross-domain knowledge.
Details
Motivation: Address the challenge of connecting vast, domain-spanning scientific information in materials science where innovation requires integrating concepts from molecular chemistry to mechanical performance, going beyond single-agent LLMs prone to hallucinations.Method: Multi-agent framework with specialized agents for problem decomposition, evidence retrieval, design parameter extraction, and graph traversal, guided by large-scale knowledge graphs to uncover latent connections across distinct knowledge domains.
Result: The full multi-agent pipeline outperforms single-shot prompting, generates sustainable PFAS-free alternatives for biomedical tubing that balance multiple performance criteria, and demonstrates effective alternation between exploitative and exploratory search strategies.
Conclusion: Establishes a framework combining knowledge graphs with multi-agent reasoning to expand materials design space, showcasing initial design candidates and the value of distributed specialization and relational reasoning for scientific discovery.
Abstract: Large Language Models (LLMs) promise to accelerate discovery by reasoning across the expanding scientific landscape. Yet, the challenge is no longer access to information but connecting it in meaningful, domain-spanning ways. In materials science, where innovation demands integrating concepts from molecular chemistry to mechanical performance, this is especially acute. Neither humans nor single-agent LLMs can fully contend with this torrent of information, with the latter often prone to hallucinations. To address this bottleneck, we introduce a multi-agent framework guided by large-scale knowledge graphs to find sustainable substitutes for per- and polyfluoroalkyl substances (PFAS)-chemicals currently under intense regulatory scrutiny. Agents in the framework specialize in problem decomposition, evidence retrieval, design parameter extraction, and graph traversal, uncovering latent connections across distinct knowledge pockets to support hypothesis generation. Ablation studies show that the full multi-agent pipeline outperforms single-shot prompting, underscoring the value of distributed specialization and relational reasoning. We demonstrate that by tailoring graph traversal strategies, the system alternates between exploitative searches focusing on domain-critical outcomes and exploratory searches surfacing emergent cross-connections. Illustrated through the exemplar of biomedical tubing, the framework generates sustainable PFAS-free alternatives that balance tribological performance, thermal stability, chemical resistance, and biocompatibility. This work establishes a framework combining knowledge graphs with multi-agent reasoning to expand the materials design space, showcasing several initial design candidates to demonstrate the approach.
[530] Joint Reward Modeling: Internalizing Chain-of-Thought for Efficient Visual Reward Models
Yankai Yang, Yancheng Long, Hongyang Wei, Wei Chen, Tianke Zhang, Kaiyu Jiang, Haonan Fan, Changyi Liu, Jiankang Chen, Kaiyu Tang, Bin Wen, Fan Yang, Tingting Gao, Han Li, Shuo Yang
Main category: cs.AI
TL;DR: JRM (Joint Reward Modeling) combines preference learning and language modeling on a shared vision-language backbone to create efficient discriminative reward models with strong semantic understanding for complex tasks like image editing.
Details
Motivation: Existing reward models for complex tasks like image editing have limitations: discriminative models align with human preferences but struggle with complex semantics due to limited reasoning supervision, while generative models offer strong semantic understanding but are costly at inference and hard to align with human preferences.Method: Proposes Joint Reward Modeling (JRM) that jointly optimizes preference learning and language modeling on a shared vision-language backbone, internalizing generative models’ semantic and reasoning capabilities into efficient discriminative representations.
Result: Achieves state-of-the-art results on MMRB2 and EditReward-Bench, and significantly improves stability and performance in downstream online reinforcement learning.
Conclusion: Joint training effectively bridges efficiency and semantic understanding in reward modeling, creating fast and accurate evaluation systems for complex multimodal tasks.
Abstract: Reward models are critical for reinforcement learning from human feedback, as they determine the alignment quality and reliability of generative models. For complex tasks such as image editing, reward models are required to capture global semantic consistency and implicit logical constraints beyond local similarity. Existing reward modeling approaches have clear limitations. Discriminative reward models align well with human preferences but struggle with complex semantics due to limited reasoning supervision. Generative reward models offer stronger semantic understanding and reasoning, but they are costly at inference time and difficult to align directly with human preferences. To this end, we propose Joint Reward Modeling (JRM), which jointly optimizes preference learning and language modeling on a shared vision-language backbone. This approach internalizes the semantic and reasoning capabilities of generative models into efficient discriminative representations, enabling fast and accurate evaluation. JRM achieves state-of-the-art results on MMRB2 and EditReward-Bench, and significantly improves stability and performance in downstream online reinforcement learning. These results show that joint training effectively bridges efficiency and semantic understanding in reward modeling.
[531] MSP-LLM: A Unified Large Language Model Framework for Complete Material Synthesis Planning
Heewoong Noh, Gyoung S. Na, Namkyeong Lee, Chanyoung Park
Main category: cs.AI
TL;DR: MSP-LLM: A unified LLM-based framework for material synthesis planning that addresses precursor prediction and synthesis operation prediction as a structured process with material class as intermediate decision variable.
Details
Motivation: Material synthesis planning remains a fundamental bottleneck in AI-driven materials discovery, requiring both precursor identification and coherent synthesis operation sequences. Existing approaches address isolated subtasks but lack a unified methodology for the entire MSP task.Method: Proposes MSP-LLM framework that formulates MSP as two subproblems: precursor prediction (PP) and synthesis operation prediction (SOP). Uses discrete material class as intermediate decision variable, incorporates hierarchical precursor types as inductive biases, and employs explicit conditioning strategy to preserve precursor information in autoregressive decoding.
Result: Extensive experiments show MSP-LLM consistently outperforms existing methods on both PP and SOP, as well as on the complete MSP task, demonstrating an effective and scalable framework for MSP.
Conclusion: MSP-LLM provides a unified LLM-based framework that can accelerate real-world materials discovery by effectively solving the material synthesis planning problem.
Abstract: Material synthesis planning (MSP) remains a fundamental and underexplored bottleneck in AI-driven materials discovery, as it requires not only identifying suitable precursor materials but also designing coherent sequences of synthesis operations to realize a target material. Although several AI-based approaches have been proposed to address isolated subtasks of MSP, a unified methodology for solving the entire MSP task has yet to be established. We propose MSP-LLM, a unified LLM-based framework that formulates MSP as a structured process composed of two constituent subproblems: precursor prediction (PP) and synthesis operation prediction (SOP). Our approach introduces a discrete material class as an intermediate decision variable that organizes both tasks into a chemically consistent decision chain. For OP, we further incorporate hierarchical precursor types as synthesis-relevant inductive biases and employ an explicit conditioning strategy that preserves precursor-related information in the autoregressive decoding state. Extensive experiments show that MSP-LLM consistently outperforms existing methods on both PP and SOP, as well as on the complete MSP task, demonstrating an effective and scalable framework for MSP that can accelerate real-world materials discovery.
[532] When Is Enough Not Enough? Illusory Completion in Search Agents
Dayoon Ko, Jihyuk Kim, Sohyeon Kim, Haeju Park, Dahyun Lee, Gunhee Kim, Moontae Lee, Kyungjae Lee
Main category: cs.AI
TL;DR: The paper introduces Epistemic Ledger to track constraint satisfaction in multi-turn reasoning agents, identifies failure patterns like illusory completion, and shows that explicit constraint-state tracking (LiveLedger) improves performance on multi-constraint problems.
Details
Motivation: Current search agents perform well on multi-hop reasoning tasks but may fail to reliably track, verify, and maintain multiple constraints simultaneously, leading to underverified answers through illusory completion.Method: Introduces Epistemic Ledger evaluation framework to track evidential support and agent beliefs for each constraint throughout multi-turn reasoning. Identifies failure patterns and proposes LiveLedger, an inference-time tracker for explicit constraint-state monitoring.
Result: LiveLedger intervention consistently improves performance, reducing underverified answers by up to 26.5% and improving overall accuracy by up to 11.6% on multi-constraint problems.
Conclusion: Explicit constraint-state tracking during execution effectively mitigates failure patterns in multi-constraint reasoning, demonstrating the importance of systematic constraint verification in multi-turn reasoning agents.
Abstract: Recent search agents leverage multi-turn reasoning and search tools to achieve strong performance on multi-hop and long-horizon benchmarks. Yet it remains unclear whether they reliably reason across all requirements by tracking, verifying, and maintaining multiple conditions in these questions. We study this capability under multi-constraint problems, where valid answers must satisfy several constraints simultaneously. We find that illusory completion frequently occurs, wherein agents believe tasks are complete despite unresolved or violated constraints, leading to underverified answers. To diagnose this behavior, we introduce the Epistemic Ledger, an evaluation framework that tracks evidential support and agents’ beliefs for each constraint throughout multi-turn reasoning. Our analysis reveals four recurring failure patterns: bare assertions, overlooked refutations, stagnation, and premature exit. Motivated by these findings, we examine whether explicit constraint-state tracking during execution mitigates these failures via LiveLedger, an inference-time tracker. This simple intervention consistently improves performance, substantially reducing underverified answers (by up to 26.5%) and improving overall accuracy (by up to 11.6%) on multi-constraint problems.
[533] VERIFY-RL: Verifiable Recursive Decomposition for Reinforcement Learning in Mathematical Reasoning
Kaleem Ullah Qasim, Jiashu Zhang, Hao Li, Muhammad Kafeel Shaheen
Main category: cs.AI
TL;DR: Verify-RL uses symbolic differentiation to create mathematically verified decompositions for training language models on mathematical problems, ensuring subproblems are simpler and solving them aids the parent task.
Details
Motivation: Existing decomposition methods for training language models on mathematical problems are heuristic and lack guarantees about subproblem simplicity, solution relevance, or mathematical grounding. There's a need for verifiable decompositions that ensure training efficiency and effectiveness.Method: Uses symbolic differentiation rules to create parent-child decompositions that satisfy three verifiable conditions: strictly decreasing structural complexity, solution containment, and formal rule derivation. This enables “verification by construction” through symbolic computation.
Result: Eliminating invalid decompositions yields significant gains - accuracy on hardest problems more than doubles from 32% to 68%, with 40% relative improvement overall compared to heuristic methods.
Conclusion: Symbolic differentiation provides a natural structure for mathematically grounded decomposition in curriculum learning for mathematical problem-solving, and verified decompositions substantially improve language model performance on complex mathematical tasks.
Abstract: Training language models to solve complex mathematical problems benefits from curriculum learning progressively training on simpler subproblems. However, existing decomposition methods are often heuristic, offering no guarantees that subproblems are simpler, that solving them aids the parent task, or that their relationships are mathematically grounded. We observe that symbolic differentiation provides a natural structure for verified decomposition: calculus rules explicitly define how expressions reduce to simpler components with provable properties. We introduce Verify-RL, a framework where every parent-child decomposition satisfies three verifiable conditions: strictly decreasing structural complexity, solution containment, and formal rule derivation. Unlike heuristic methods where a significant fraction of decompositions are invalid our properties admit automatic verification through symbolic computation, achieving “verification by construction” Experiments demonstrate that eliminating invalid decompositions yields sizable gains, accuracy on the hardest problems more than doubles from 32% to 68%, with a 40% relative improvement overall.
[534] M2A: Multimodal Memory Agent with Dual-Layer Hybrid Memory for Long-Term Personalized Interactions
Junyu Feng, Binxiao Xu, Jiayi Chen, Mengyu Dai, Cenyang Wu, Haodong Li, Bohan Zeng, Yunliu Xie, Hao Liang, Ming Lu, Wentao Zhang
Main category: cs.AI
TL;DR: M2A is an agentic dual-layer hybrid memory system for personalized multimodal question answering in long-term interactions, enabling continuous evolution of user concepts and preferences beyond context window limits.
Details
Motivation: Existing personalized multimodal models struggle with long-term interactions where conversation history exceeds context windows, as they can't continuously absorb and leverage users' evolving concepts, aliases, and preferences over weeks or months.Method: Proposes M2A with two collaborative agents: ChatAgent manages user interactions and decides when to query/update memory, while MemoryManager handles detailed operations on a dual-layer memory bank (RawMessageStore for immutable logs and SemanticMemoryStore for high-level observations). Also develops a data synthesis pipeline to inject concept-grounded sessions into long conversations.
Result: M2A significantly outperforms baselines, demonstrating that transforming personalization from one-shot configuration to a co-evolving memory mechanism enables high-quality individualized responses in long-term multimodal interactions.
Conclusion: The agentic dual-layer hybrid memory system provides a viable path for continuous personalization in long-term multimodal interactions, moving beyond static concept initialization to dynamic co-evolution with users.
Abstract: This work addresses the challenge of personalized question answering in long-term human-machine interactions: when conversational history spans weeks or months and exceeds the context window, existing personalization mechanisms struggle to continuously absorb and leverage users’ incremental concepts, aliases, and preferences. Current personalized multimodal models are predominantly static-concepts are fixed at initialization and cannot evolve during interactions. We propose M2A, an agentic dual-layer hybrid memory system that maintains personalized multimodal information through online updates. The system employs two collaborative agents: ChatAgent manages user interactions and autonomously decides when to query or update memory, while MemoryManager breaks down memory requests from ChatAgent into detailed operations on the dual-layer memory bank, which couples a RawMessageStore (immutable conversation log) with a SemanticMemoryStore (high-level observations), providing memories at different granularities. In addition, we develop a reusable data synthesis pipeline that injects concept-grounded sessions from Yo’LLaVA and MC-LLaVA into LoCoMo long conversations while preserving temporal coherence. Experiments show that M2A significantly outperforms baselines, demonstrating that transforming personalization from one-shot configuration to a co-evolving memory mechanism provides a viable path for high-quality individualized responses in long-term multimodal interactions. The code is available at https://github.com/Little-Fridge/M2A.
[535] SleepMaMi: A Universal Sleep Foundation Model for Integrating Macro- and Micro-structures
Keondo Park, Younghoon Na, Yourim Choi, Hyunwoo Ryu, Hyun-Woo Shin, Hyung-Sin Kim
Main category: cs.AI
TL;DR: SleepMaMi is a sleep foundation model that captures both macro-structure (full-night sleep architecture) and micro-structure (fine-grained signal morphologies) from polysomnography data using a hierarchical dual-encoder design.
Details
Motivation: Current sleep medicine relies on task-specific models focusing on localized micro-structure features, neglecting the rich multi-modal context of PSG and failing to capture global macro-structure of full-night sleep.Method: Hierarchical dual-encoder design: Macro-Encoder models full-night temporal dependencies via Demographic-Guided Contrastive Learning; Micro-Encoder captures short-term biosignal characteristics via hybrid Masked Autoencoder and multi-modal contrastive objectives.
Result: Pre-trained on >20,000 PSG recordings (158K hours), SleepMaMi outperforms existing foundation models across diverse downstream tasks, demonstrating superior generalizability and label-efficient adaptation for clinical sleep analysis.
Conclusion: SleepMaMi successfully bridges the gap between localized micro-structure analysis and global sleep architecture understanding, offering a unified foundation model for sleep medicine with strong performance and generalizability.
Abstract: While the shift toward unified foundation models has revolutionized many deep learning domains, sleep medicine remains largely restricted to task-specific models that focus on localized micro-structure features. These approaches often neglect the rich, multi-modal context of Polysomnography (PSG) and fail to capture the global macro-structure of a full night’s sleep. To address this, we introduce SleepMaMi , a Sleep Foundation Model engineered to master both hour-long sleep architectures and fine-grained signal morphologies. Our framework utilizes a hierarchical dual-encoder design: a Macro-Encoder to model full-night temporal dependencies and a Micro-Encoder to capture short-term characteristics from biosignals. Macro-Encoder is trained via Demographic-Guided Contrastive Learning, which aligns overnight sleep patterns with objective subject metadata, such as age, sex and BMI to refine global representations. Micro-Encoder is optimized via a hybrid Masked Autoencoder (MAE) and multi-modal contrastive objective. Pre-trained on a massive corpus of $>$20,000 PSG recordings (158K hours),SleepMaMi outperforms existing foundation models across a diverse suite of downstream tasks, demonstrating superior generalizability and label-efficient adaptation for clinical sleep analysis.
[536] Efficient Table Retrieval and Understanding with Multimodal Large Language Models
Zhuoyan Xu, Haoyang Fang, Boran Han, Bonan Min, Bernie Wang, Cuixiong Hu, Shuai Zhang
Main category: cs.AI
TL;DR: TabRAG is a framework that enables multimodal LLMs to answer queries over large collections of table images by combining retrieval, reranking, and reasoning components.
Details
Motivation: Real-world tabular data often exists in image form (financial reports, handwritten records, document scans), but current MLLMs for table understanding assume tables are readily available. A more practical scenario requires identifying and reasoning over relevant tables from large-scale collections to answer user queries.Method: Three-stage framework: 1) Retrieve candidate tables using jointly trained visual-text foundation models, 2) Fine-grained reranking of candidates using MLLMs, 3) Employ MLLMs to reason over selected tables for answer generation.
Result: Significant improvements over existing methods: 7.0% better retrieval recall and 6.1% better answer accuracy on a new dataset of 88,161 training and 9,819 testing samples across 8 benchmarks with 48,504 unique tables.
Conclusion: TabRAG offers a practical solution for real-world table understanding tasks by enabling MLLMs to effectively handle large collections of table images through integrated retrieval and reasoning.
Abstract: Tabular data is frequently captured in image form across a wide range of real-world scenarios such as financial reports, handwritten records, and document scans. These visual representations pose unique challenges for machine understanding, as they combine both structural and visual complexities. While recent advances in Multimodal Large Language Models (MLLMs) show promising results in table understanding, they typically assume the relevant table is readily available. However, a more practical scenario involves identifying and reasoning over relevant tables from large-scale collections to answer user queries. To address this gap, we propose TabRAG, a framework that enables MLLMs to answer queries over large collections of table images. Our approach first retrieves candidate tables using jointly trained visual-text foundation models, then leverages MLLMs to perform fine-grained reranking of these candidates, and finally employs MLLMs to reason over the selected tables for answer generation. Through extensive experiments on a newly constructed dataset comprising 88,161 training and 9,819 testing samples across 8 benchmarks with 48,504 unique tables, we demonstrate that our framework significantly outperforms existing methods by 7.0% in retrieval recall and 6.1% in answer accuracy, offering a practical solution for real-world table understanding tasks.
[537] ONTrust: A Reference Ontology of Trust
Glenda Amaral, Tiago Prince Sales, Riccardo Baratella, Daniele Porello, Renata Guizzardi, Giancarlo Guizzardi
Main category: cs.AI
TL;DR: A reference ontology (ONTrust) for formally modeling trust concepts, types, influencing factors, and risk in trust relations, applied to various domains including trustworthy AI and affective Human-AI teaming.
Details
Motivation: Recent AI advances making machines more humanlike and decentralized technologies create new forms of trust that need proper conceptualization for building trustworthy systems. Trust is crucial for adoption of these technologies, requiring formal models understandable by both humans and machines.Method: Developed a Reference Ontology of Trust (ONTrust) grounded in the Unified Foundational Ontology and specified in OntoUML. The ontology formally characterizes trust concepts, types, influencing factors, and risk emergence from trust relations.
Result: ONTrust has been applied in multiple initiatives including conceptual modeling, enterprise architecture design, language evaluation, trust management, requirements engineering, and trustworthy AI in affective Human-AI teaming. Demonstrated through case studies from literature.
Conclusion: ONTrust provides a solid ontological foundation for trust that supports information modeling, automated reasoning, integration, and semantic interoperability, essential for building trustworthy systems in AI and decentralized technologies.
Abstract: Trust has stood out more than ever in the light of recent innovations. Some examples are advances in artificial intelligence that make machines more and more humanlike, and the introduction of decentralized technologies (e.g. blockchains), which creates new forms of (decentralized) trust. These new developments have the potential to improve the provision of products and services, as well as to contribute to individual and collective well-being. However, their adoption depends largely on trust. In order to build trustworthy systems, along with defining laws, regulations and proper governance models for new forms of trust, it is necessary to properly conceptualize trust, so that it can be understood both by humans and machines. This paper is the culmination of a long-term research program of providing a solid ontological foundation on trust, by creating reference conceptual models to support information modeling, automated reasoning, information integration and semantic interoperability tasks. To address this, a Reference Ontology of Trust (ONTrust) was developed, grounded on the Unified Foundational Ontology and specified in OntoUML, which has been applied in several initiatives, to demonstrate, for example, how it can be used for conceptual modeling and enterprise architecture design, for language evaluation and (re)design, for trust management, for requirements engineering, and for trustworthy artificial intelligence (AI) in the context of affective Human-AI teaming. ONTrust formally characterizes the concept of trust and its different types, describes the different factors that can influence trust, as well as explains how risk emerges from trust relations. To illustrate the working of ONTrust, the ontology is applied to model two case studies extracted from the literature.
[538] Geo-Code: A Code Framework for Reverse Code Generation from Geometric Images Based on Two-Stage Multi-Agent Evolution
Zhenyu Wu, Yanxi Long, Jian Li, Hua Huang
Main category: cs.AI
TL;DR: Geo-coder: A multi-agent inverse programming framework for geometric image reconstruction that preserves geometric semantics for multimodal reasoning.
Details
Motivation: Current inverse graphics methods struggle with accurately reconstructing complex geometric details, losing key constraints or causing structural distortion, which limits their effectiveness in multimodal reasoning tasks.Method: Two-stage approach: 1) Geometric modeling via pixel-wise anchoring using visual operators and large models, 2) Metric-driven code evolution with synthesis-rendering-validation closed loop using bidirectional visual feedback for self-correction.
Result: Achieves substantial lead in geometric reconstruction accuracy and visual consistency; reconstructed images perform equivalently to originals in multimodal reasoning tasks; open-sourced dataset (1,500+ samples) and GeocodeLM model.
Conclusion: Geo-coder effectively preserves core geometric semantics, validating framework robustness and providing foundation for subsequent research in geometric image understanding and multimodal reasoning.
Abstract: Program code serves as a bridge linking vision and logic, providing a feasible supervisory approach for enhancing the multimodal reasoning capability of large models through geometric operations such as auxiliary line construction and perspective transformation. Nevertheless, current inverse graphics methods face tremendous challenges in accurately reconstructing complex geometric details, which often results in the loss of key geometric constraints or structural distortion. To address this bottleneck, we propose Geo-coder – the first inverse programming framework for geometric images based on a multi-agent system. Our method innovatively decouples the process into geometric modeling via pixel-wise anchoring and metric-driven code evolution: Stage 1 leverages the complementary advantages of visual operators and large models to achieve precise capture of pixel coordinates and visual attributes; Stage 2 introduces a synthesis-rendering-validation closed loop, where bidirectional visual feedback drives the self-correction of code. Extensive experiments demonstrate that Geo-coder achieves a substantial lead in both geometric reconstruction accuracy and visual consistency. Notably, by effectively preserving the core geometric semantics, the images reconstructed with our method exhibit equivalent performance to the original ones in multimodal reasoning tasks, which fully validates the robustness of the framework. Finally, to further reduce research costs, we have open-sourced the Geo-coder dataset constructed on the GeoCode framework, which contains more than 1,500 samples. On this basis, we have also open-sourced the GeocodeLM model, laying a solid data and model foundation for subsequent research in this field.
[539] Humanizing AI Grading: Student-Centered Insights on Fairness, Trust, Consistency and Transparency
Bahare Riahi, Veronica Catete
Main category: cs.AI
TL;DR: Study examines student perceptions of AI grading systems in computer science education, focusing on ethical concerns like fairness, trust, consistency, and transparency compared to human grading.
Details
Motivation: To investigate how students perceive AI grading systems in educational contexts, particularly examining ethical dimensions like fairness, trust, consistency, and transparency, using Jobin's (2019) ethical principles framework.Method: Comparative study of AI-generated feedback vs. human-graded feedback in an undergraduate computer science course (n=27) with block-based programming final project, guided by ethical principles framework.
Result: Students expressed concerns about AI’s lack of contextual understanding and personalization; findings suggest AI systems need to reflect human judgment, flexibility, and empathy to be equitable and trustworthy.
Conclusion: AI grading systems should serve as supplementary tools under human oversight, with design principles that humanize AI in learning environments while amplifying student voices in ethics-centered assessment practices.
Abstract: This study investigates students’ perceptions of Artificial Intelligence (AI) grading systems in an undergraduate computer science course (n = 27), focusing on a block-based programming final project. Guided by the ethical principles framework articulated by Jobin (2019), our study examines fairness, trust, consistency, and transparency in AI grading by comparing AI-generated feedback with original human-graded feedback. Findings reveal concerns about AI’s lack of contextual understanding and personalization. We recommend that equitable and trustworthy AI systems reflect human judgment, flexibility, and empathy, serving as supplementary tools under human oversight. This work contributes to ethics-centered assessment practices by amplifying student voices and offering design principles for humanizing AI in designed learning environments.
[540] Learning to Continually Learn via Meta-learning Agentic Memory Designs
Yiming Xiong, Shengran Hu, Jeff Clune
Main category: cs.AI
TL;DR: ALMA is a framework that meta-learns memory designs for agentic systems to enable continual learning, replacing hand-engineered memory with automated discovery of memory architectures.
Details
Motivation: Foundation models lack statefulness, limiting agentic systems' continual learning capabilities for long-horizon reasoning. Existing memory designs are human-crafted and fixed, unable to adapt to diverse, non-stationary real-world tasks.Method: ALMA uses a Meta Agent that searches over memory designs expressed as executable code in an open-ended manner, allowing discovery of arbitrary memory designs including database schemas and their retrieval/update mechanisms.
Result: Experiments across four sequential decision-making domains show learned memory designs enable more effective and efficient learning from experience than state-of-the-art human-crafted memory designs on all benchmarks.
Conclusion: ALMA represents a step toward self-improving AI systems that learn to be adaptive, continual learners when developed and deployed safely.
Abstract: The statelessness of foundation models bottlenecks agentic systems’ ability to continually learn, a core capability for long-horizon reasoning and adaptation. To address this limitation, agentic systems commonly incorporate memory modules to retain and reuse past experience, aiming for continual learning during test time. However, most existing memory designs are human-crafted and fixed, which limits their ability to adapt to the diversity and non-stationarity of real-world tasks. In this paper, we introduce ALMA (Automated meta-Learning of Memory designs for Agentic systems), a framework that meta-learns memory designs to replace hand-engineered memory designs, therefore minimizing human effort and enabling agentic systems to be continual learners across diverse domains. Our approach employs a Meta Agent that searches over memory designs expressed as executable code in an open-ended manner, theoretically allowing the discovery of arbitrary memory designs, including database schemas as well as their retrieval and update mechanisms. Extensive experiments across four sequential decision-making domains demonstrate that the learned memory designs enable more effective and efficient learning from experience than state-of-the-art human-crafted memory designs on all benchmarks. When developed and deployed safely, ALMA represents a step toward self-improving AI systems that learn to be adaptive, continual learners.
[541] AISAC: An Integrated multi-agent System for Transparent, Retrieval-Grounded Scientific Assistance
Chandrachur Bhattacharya, Sibendu Som
Main category: cs.AI
TL;DR: AISAC is a modular multi-agent runtime for scientific reasoning with governance features like role semantics, budgeted context management, traceable execution, and reproducible tool interactions.
Details
Motivation: To create a governed execution substrate for deploying agentic AI in scientific practice, addressing requirements like explicit role semantics, budgeted context management, traceable execution, and reproducible tool/knowledge interactions.Method: AISAC implements four structural guarantees: declarative agent registration with runtime-enforced role semantics, budgeted orchestration with context/delegation limits, role-aligned memory access across layers, and trace-driven transparency. Uses hybrid persistent memory (SQLite + FAISS), governed retrieval with agent-scoped RAG, structured tool execution with schema validation, and configuration-driven bootstrap.
Result: Currently deployed across multiple scientific workflows at Argonne National Laboratory including combustion science, materials research, and energy process safety, demonstrating its use as a reusable substrate for domain-specialized AI scientific assistants.
Conclusion: AISAC provides a transparent, modular multi-agent runtime that operationalizes key requirements for deploying agentic AI in scientific practice, enabling long-horizon, evidence-grounded scientific reasoning with governance and reproducibility guarantees.
Abstract: AI Scientific Assistant Core (AISAC) is a transparent, modular multi-agent runtime developed at Argonne National Laboratory to support long-horizon, evidence-grounded scientific reasoning. Rather than proposing new agent algorithms or claiming autonomous scientific discovery, AISAC contributes a governed execution substrate that operationalizes key requirements for deploying agentic AI in scientific practice, including explicit role semantics, budgeted context management, traceable execution, and reproducible interaction with tools and knowledge. AISAC enforces four structural guarantees for scientific reasoning: (1) declarative agent registration with runtime-enforced role semantics and automatic system prompt generation; (2) budgeted orchestration via explicit per-turn context and delegation depth limits; (3) role-aligned memory access across episodic, dialogue, and evidence layers; and (4) trace-driven transparency through persistent execution records and a live event-stream interface. These guarantees are implemented through hybrid persistent memory (SQLite and dual FAISS indices), governed retrieval with agent-scoped RAG, structured tool execution with schema validation, and a configuration-driven bootstrap mechanism that enables project specific extension without modifying the shared core. AISAC is currently deployed across multiple scientific workflows at Argonne, including combustion science, materials research, and energy process safety, demonstrating its use as a reusable substrate for domain-specialized AI scientific assistants.
[542] Disentangled Instrumental Variables for Causal Inference with Networked Observational Data
Zhirong Huang, Debo Cheng, Guixian Zhang, Yi Wang, Jiuyong Li, Shichao Zhang
Main category: cs.AI
TL;DR: DisIV framework disentangles individual-specific components from networked data to create valid instrumental variables for causal inference with latent confounders.
Details
Motivation: Instrumental variables are essential for addressing unobservable confounders, but their exogeneity assumptions are challenging in networked data where existing methods mix shared environment-induced endogenous correlations with individual-specific exogenous variation.Method: DisIV uses network homogeneity as inductive bias and employs structural disentanglement mechanism to extract individual-specific components as latent IVs, with causal validity constrained through explicit orthogonality and exclusion conditions.
Result: Extensive semi-synthetic experiments on real-world datasets show DisIV consistently outperforms state-of-the-art baselines in causal effect estimation under network-induced confounding.
Conclusion: The DisIV framework successfully addresses the challenge of creating valid instrumental variables from networked observational data by disentangling individual-specific components, enabling more accurate causal inference with latent confounders.
Abstract: Instrumental variables (IVs) are crucial for addressing unobservable confounders, yet their stringent exogeneity assumptions pose significant challenges in networked data. Existing methods typically rely on modelling neighbour information when recovering IVs, thereby inevitably mixing shared environment-induced endogenous correlations and individual-specific exogenous variation, leading the resulting IVs to inherit dependence on unobserved confounders and to violate exogeneity. To overcome this challenge, we propose $\underline{Dis}$entangled $\underline{I}$nstrumental $\underline{V}$ariables (DisIV) framework, a novel method for causal inference based on networked observational data with latent confounders. DisIV exploits network homogeneity as an inductive bias and employs a structural disentanglement mechanism to extract individual-specific components that serve as latent IVs. The causal validity of the extracted IVs is constrained through explicit orthogonality and exclusion conditions. Extensive semi-synthetic experiments on real-world datasets demonstrate that DisIV consistently outperforms state-of-the-art baselines in causal effect estimation under network-induced confounding.
[543] Conversational No-code, Multi-agentic Disease Module Identification and Drug Repurposing Prediction with ChatDRex
Simon Süwer, Kester Bagemihl, Sylvie Baier, Lucia Dicunta, Markus List, Jan Baumbach, Andreas Maier, Fernando M. Delgado-Chaves
Main category: cs.AI
TL;DR: ChatDRex is a conversation-based multi-agent system that enables natural language access to biomedical knowledge for network-based drug repurposing prediction, democratizing bioinformatics for non-experts.
Details
Motivation: Drug repurposing is time-efficient and cost-effective but requires complex bioinformatic analyses that involve fragmented tools and heterogeneous data, creating barriers for clinical experts without computer science expertise.Method: A multi-agent system with specialized agents for query routing, data retrieval from the NeDRex knowledge graph, network analysis, literature mining, drug repurposing prediction, functional coherence evaluation, and result visualization, with natural language interface and hallucination detection.
Result: ChatDRex provides public access to complex bioinformatic analyses through natural language, enabling clinical experts to generate drug repurposing hypotheses without requiring computer science expertise.
Conclusion: ChatDRex democratizes access to bioinformatics for drug repurposing, accelerating discovery of novel therapies and advancing personalized medicine by enabling clinical experts to explore repurposing opportunities through natural language interfaces.
Abstract: Repurposing approved drugs offers a time-efficient and cost-effective alternative to traditional drug development. However, in silico prediction of repurposing candidates is challenging and requires the effective collaboration of specialists in various fields, including pharmacology, medicine, biology, and bioinformatics. Fragmented, specialized algorithms and tools often address only narrow aspects of the overall problem. Heterogeneous, unstructured data landscapes require the expertise of specialized users. Hence, these data services do not integrate smoothly across workflows. With ChatDRex, we present a conversation-based, multi-agent system that facilitates the execution of complex bioinformatic analyses aiming for network-based drug repurposing prediction. It builds on the integrated systems medicine knowledge graph (NeDRex KG). ChatDRex provides natural language access to its extensive biomedical knowledge base. It integrates bioinformatics agents for network analysis, literature mining, and drug repurposing. These are complemented by agents that evaluate functional coherence for in silico validation. Its flexible multi-agent design assigns specific tasks to specialized agents, including query routing, data retrieval, algorithm execution, and result visualization. A dedicated reasoning module keeps the user in the loop and allows for hallucination detection. By enabling physicians and researchers without computer science expertise to control complex analyses with natural language, ChatDRex democratizes access to bioinformatics as an important resource for drug repurposing. It enables clinical experts to generate hypotheses and explore drug repurposing opportunities, ultimately accelerating the discovery of novel therapies and advancing personalized medicine and translational research. ChatDRex is publicly available at apps.cosy.bio/chatdrex.
[544] Do Multi-Agents Dream of Electric Screens? Achieving Perfect Accuracy on AndroidWorld Through Task Decomposition
Pierre-Louis Favreau, Jean-Pierre Lo, Clement Guiguet, Charles Simon-Meunier, Nicolas Dehandschoewercker, Allen G. Roush, Judah Goldfeder, Ravid Shwartz-Ziv
Main category: cs.AI
TL;DR: Minitap is a multi-agent system that achieves 100% success on AndroidWorld benchmark by addressing single-agent failures through specialized agents, verified text input, and meta-cognitive reasoning.
Details
Motivation: Single-agent architectures fail on mobile device automation tasks due to context pollution from mixed reasoning traces, undetected text input failures, and repetitive action loops without escape mechanisms.Method: Multi-agent decomposition with six specialized agents, deterministic post-validation of text input against device state, and meta-cognitive reasoning that detects cycles and triggers strategy changes.
Result: Achieves 100% success on AndroidWorld benchmark (116 tasks), surpassing human performance (80%). Multi-agent decomposition contributes +21 points, verified execution +7 points, meta-cognition +9 points over baselines.
Conclusion: Minitap demonstrates that targeted multi-agent decomposition with specialized capabilities, verified execution, and meta-cognitive reasoning can fully solve complex mobile device automation tasks.
Abstract: We present Minitap, a multi-agent system that achieves 100% success on the AndroidWorld benchmark, the first to fully solve all 116 tasks and surpassing human performance (80%). We first analyze why single-agent architectures fail: context pollution from mixed reasoning traces, silent text input failures undetected by the agent, and repetitive action loops without escape. Minitap addresses each failure through targeted mechanisms: cognitive separation across six specialized agents, deterministic post-validation of text input against device state, and meta-cognitive reasoning that detects cycles and triggers strategy changes. Ablations show multi-agent decomposition contributes +21 points over single-agent baselines; verified execution adds +7 points; meta-cognition adds +9 points. We release Minitap as open-source software. https://github.com/minitap-ai/mobile-use
[545] Data Darwinism Part I: Unlocking the Value of Scientific Data for Pre-training
Yiwei Qin, Zhen Huang, Tiantian Mi, Weiye Si, Chenyang Zhou, Qipeng Guo, Siyuan Feng, Pengfei Liu
Main category: cs.AI
TL;DR: Data Darwinism proposes a 10-level taxonomy for data-model co-evolution where advanced models generate better training data for next-generation systems, validated on scientific literature with significant performance gains.
Details
Motivation: Data quality is crucial for foundation model performance but lacks systematic processing frameworks. The paper addresses this gap by proposing a co-evolutionary approach where better models create better training data.Method: Introduces Data Darwinism taxonomy (L0-L9) and constructs Darwin-Science corpus (900B tokens, L0-L5). Uses frontier LLMs for generative refinement (L4) and cognitive completion (L5) to bridge learnability gaps in raw scientific text. Pre-trains contamination-free baseline models and performs continued pre-training on Darwin-Science.
Result: Models trained on Darwin-Science outperform baselines by +2.12 (3B) and +2.95 (7B) points across 20+ benchmarks, with domain-aligned tasks showing +5.60 and +8.40 point gains. Systematic progression to L5 yields +1.36 total gain, confirming higher-level processing unlocks latent data value.
Conclusion: Data-model co-evolution through systematic data processing (Data Darwinism) significantly improves foundation model performance, especially for domain-specific tasks. The framework enables principled development and the released corpus/models facilitate further research.
Abstract: Data quality determines foundation model performance, yet systematic processing frameworks are lacking. We introduce Data Darwinism, a ten-level taxonomy (L0-L9) that conceptualizes data-model co-evolution: advanced models produce superior data for next-generation systems. We validate this on scientific literature by constructing Darwin-Science, a 900B-token corpus (L0-L5). We identify a learnability gap in raw scientific text, which we bridge via L4 (Generative Refinement) and L5 (Cognitive Completion) using frontier LLMs to explicate reasoning and terminology. To ensure rigorous attribution, we pre-trained daVinci-origin-3B/7B models from scratch, excluding scientific content to create contamination-free baselines. After 600B tokens of continued pre-training, Darwin-Science outperforms baselines by +2.12 (3B) and +2.95 (7B) points across 20+ benchmarks, rising to +5.60 and +8.40 points on domain-aligned tasks. Systematic progression to L5 yields a +1.36 total gain, confirming that higher-level processing unlocks latent data value. We release the Darwin-Science corpus and daVinci-origin models to enable principled, co-evolutionary development.
[546] Time Series Reasoning via Process-Verifiable Thinking Data Synthesis and Scheduling for Tailored LLM Reasoning
Jiahui Zhou, Dan Li, Boxin Li, Xiao Zhang, Erli Meng, Lin Li, Zhuomin Chen, Jian Lou, See-Kiong Ng
Main category: cs.AI
TL;DR: VeriTime is a framework that enhances LLMs for time series reasoning through synthetic data generation, intelligent data scheduling, and reinforcement learning with process-verifiable annotations.
Details
Motivation: Current LLMs lack effective reasoning capabilities for time series tasks due to absence of curated Chain-of-Thought data, inefficient data scheduling, and lack of RL algorithms tailored for time series reasoning.Method: Three-stage approach: 1) Data synthesis pipeline creating TS-text multimodal dataset with verifiable annotations, 2) Data scheduling mechanism organizing training by difficulty and task taxonomy, 3) Two-stage RL finetuning with multi-objective rewards using process-level CoT data.
Result: VeriTime substantially boosts LLM performance across diverse time series reasoning tasks, enabling compact 3B-4B models to achieve reasoning capabilities comparable to or exceeding larger proprietary LLMs.
Conclusion: The framework successfully addresses key challenges in adapting LLMs for time series reasoning through systematic data creation, scheduling, and reinforcement learning approaches.
Abstract: Time series is a pervasive data type across various application domains, rendering the reasonable solving of diverse time series tasks a long-standing goal. Recent advances in large language models (LLMs), especially their reasoning abilities unlocked through reinforcement learning (RL), have opened new opportunities for tackling tasks with long Chain-of-Thought (CoT) reasoning. However, leveraging LLM reasoning for time series remains in its infancy, hindered by the absence of carefully curated time series CoT data for training, limited data efficiency caused by underexplored data scheduling, and the lack of RL algorithms tailored for exploiting such time series CoT data. In this paper, we introduce VeriTime, a framework that tailors LLMs for time series reasoning through data synthesis, data scheduling, and RL training. First, we propose a data synthesis pipeline that constructs a TS-text multimodal dataset with process-verifiable annotations. Second, we design a data scheduling mechanism that arranges training samples according to a principled hierarchy of difficulty and task taxonomy. Third, we develop a two-stage reinforcement finetuning featuring fine-grained, multi-objective rewards that leverage verifiable process-level CoT data. Extensive experiments show that VeriTime substantially boosts LLM performance across diverse time series reasoning tasks. Notably, it enables compact 3B, 4B models to achieve reasoning capabilities on par with or exceeding those of larger proprietary LLMs.
[547] Enhancing Mathematical Problem Solving in LLMs through Execution-Driven Reasoning Augmentation
Aditya Basarkar, Benyamin Tabarsi, Tiffany Barnes, Dongkuan Xu
Main category: cs.AI
TL;DR: IIPC is a multi-agent LLM system for mathematical reasoning that iteratively refines programmatic reasoning chains using execution feedback while maintaining high-level contextual focus through Chain-of-Thought abilities.
Details
Motivation: Current multi-agent LLM systems for mathematical reasoning lack reliably revisable representations of reasoning processes, operate in rigid sequential pipelines that can't correct earlier steps, rely on heuristic self-evaluation that fails to identify errors, and suffer from programmatic context distracting language models and degrading accuracy.Method: Iteratively Improved Program Construction (IIPC) refines programmatic reasoning chains iteratively, combining execution feedback with the native Chain-of-Thought abilities of base LLMs to maintain high-level contextual focus.
Result: IIPC surpasses competing approaches in the majority of reasoning benchmarks on multiple base LLMs.
Conclusion: IIPC provides an effective method for improving mathematical reasoning in LLMs through iterative program construction that maintains contextual focus while allowing error correction.
Abstract: Mathematical problem solving is a fundamental benchmark for assessing the reasoning capabilities of artificial intelligence and a gateway to applications in education, science, and engineering where reliable symbolic reasoning is essential. Although recent advances in multi-agent LLM-based systems have enhanced their mathematical reasoning capabilities, they still lack a reliably revisable representation of the reasoning process. Existing agents either operate in rigid sequential pipelines that cannot correct earlier steps or rely on heuristic self-evaluation that can fail to identify and fix errors. In addition, programmatic context can distract language models and degrade accuracy. To address these gaps, we introduce Iteratively Improved Program Construction (IIPC), a reasoning method that iteratively refines programmatic reasoning chains and combines execution feedback with the native Chain-of-thought abilities of the base LLM to maintain high-level contextual focus. IIPC surpasses competing approaches in the majority of reasoning benchmarks on multiple base LLMs. All code and implementations are released as open source.
[548] LQA: A Lightweight Quantized-Adaptive Framework for Vision-Language Models on the Edge
Xin Wang, Hualin Zhou, Sheng Guang Wang, Ting Dang, Yu Zhang, Hong Jia, Tao Gu
Main category: cs.AI
TL;DR: LQA is a lightweight, quantized-adaptive framework for Vision-Language Models that enables efficient on-device deployment through modality-aware quantization and gradient-free test-time adaptation.
Details
Motivation: Deploying VLMs on edge devices faces challenges from resource constraints and performance degradation under distribution shifts. Existing test-time adaptation methods are too resource-intensive for on-device deployment.Method: Proposes LQA framework with: 1) Selective Hybrid Quantization (SHQ) - modality-aware quantization strategy, and 2) Quantized, gradient-free adaptation mechanism for efficient test-time adaptation on resource-constrained hardware.
Result: Improves adaptation performance by 4.5%, uses less memory than full-precision models, achieves up to 19.9× lower memory usage than gradient-based TTA methods across seven open-source datasets.
Conclusion: LQA offers a practical pathway for robust, privacy-preserving, and efficient VLM deployment on edge devices by combining efficient quantization with gradient-free adaptation.
Abstract: Deploying Vision-Language Models (VLMs) on edge devices is challenged by resource constraints and performance degradation under distribution shifts. While test-time adaptation (TTA) can counteract such shifts, existing methods are too resource-intensive for on-device deployment. To address this challenge, we propose LQA, a lightweight, quantized-adaptive framework for VLMs that combines a modality-aware quantization strategy with gradient-free test-time adaptation. We introduce Selective Hybrid Quantization (SHQ) and a quantized, gradient-free adaptation mechanism to enable robust and efficient VLM deployment on resource-constrained hardware. Experiments across both synthetic and real-world distribution shifts show that LQA improves overall adaptation performance by 4.5%, uses less memory than full-precision models, and significantly outperforms gradient-based TTA methods, achieving up to 19.9$\times$ lower memory usage across seven open-source datasets. These results demonstrate that LQA offers a practical pathway for robust, privacy-preserving, and efficient VLM deployment on edge devices.
[549] Emergent Misalignment is Easy, Narrow Misalignment is Hard
Anna Soligo, Edward Turner, Senthooran Rajamanoharan, Neel Nanda
Main category: cs.AI
TL;DR: Large language models finetuned on narrow harmful datasets can develop emergent misalignment, where they give stereotypically evil responses across diverse settings, revealing concerning inductive biases in LLM generalization.
Details
Motivation: To understand how finetuning LLMs on narrowly harmful datasets leads to emergent misalignment across unrelated settings, and to investigate the inductive biases governing learning and generalization in LLMs.Method: Use emergent misalignment as a case study to analyze inductive biases, identify linear representations of both general misalignment and narrow solutions, compare their properties using KL divergence loss, and evaluate stability, efficiency, and robustness.
Result: Found that general misalignment achieves lower loss, is more robust to perturbations, and is more influential in pre-training distribution compared to narrow solutions, revealing concerning generalization patterns in LLMs.
Conclusion: This work isolates concrete representations of general misalignment for monitoring and mitigation, providing a detailed case study and preliminary metrics for investigating how inductive biases shape generalization in LLMs.
Abstract: Finetuning large language models on narrowly harmful datasets can cause them to become emergently misaligned, giving stereotypically `evil’ responses across diverse unrelated settings. Concerningly, a pre-registered survey of experts failed to predict this result, highlighting our poor understanding of the inductive biases governing learning and generalisation in LLMs. We use emergent misalignment (EM) as a case study to investigate these inductive biases and find that models can just learn the narrow dataset task, but that the general solution appears to be more stable and more efficient. To establish this, we build on the result that different EM finetunes converge to the same linear representation of general misalignment, which can be used to mediate misaligned behaviour. We find a linear representation of the narrow solution also exists, and can be learned by introducing a KL divergence loss. Comparing these representations reveals that general misalignment achieves lower loss, is more robust to perturbations, and is more influential in the pre-training distribution. This work isolates a concrete representation of general misalignment for monitoring and mitigation. More broadly, it offers a detailed case study and preliminary metrics for investigating how inductive biases shape generalisation in LLMs. We open-source all code, datasets and model finetunes.
[550] ToolSelf: Unifying Task Execution and Self-Reconfiguration via Tool-Driven Intrinsic Adaptation
Jingqi Zhou, Sheng Wang, DeZhao Deng, Junwen Lu, Junwei Su, Qintong Li, Jiahui Gao, Hao Wu, Jiyue Jiang, Lingpeng Kong, Chuan Wu
Main category: cs.AI
TL;DR: ToolSelf enables LLM agents to autonomously reconfigure themselves during task execution by treating configuration updates as callable tools, achieving self-adaptive behavior through unified action space and specialized training.
Details
Motivation: Current LLM-based agentic systems have static configurations fixed before execution, limiting adaptation to evolving task dynamics. Existing approaches using manual orchestration or heuristics suffer from poor generalization and fragmented optimization.Method: ToolSelf abstracts configuration updates as callable tools, unifying task execution and self-adjustment into a single action space. Uses Configuration-Aware Two-stage Training (CAT) combining rejection sampling fine-tuning with trajectory-level reinforcement learning to internalize meta-capabilities.
Result: Extensive experiments show ToolSelf rivals specialized workflows while generalizing to novel tasks, achieving 24.1% average performance gain across diverse benchmarks.
Conclusion: ToolSelf enables agents to transform from passive executors into dual managers of both task and self, illuminating a path toward truly self-adaptive agents through runtime self-reconfiguration.
Abstract: Agentic systems powered by Large Language Models (LLMs) have demonstrated remarkable potential in tackling complex, long-horizon tasks. However, their efficacy is fundamentally constrained by static configurations governing agent behaviors, which are fixed prior to execution and fail to adapt to evolving task dynamics. Existing approaches, relying on manual orchestration or heuristic-based patches, often struggle with poor generalization and fragmented optimization. To transcend these limitations, we propose ToolSelf, a novel paradigm enabling tool-driven runtime self-reconfiguration. By abstracting configuration updates as a callable tool, ToolSelf unifies task execution and self-adjustment into a single action space, achieving a phase transition from external rules to intrinsic parameters. Agents can thereby autonomously update their sub-goals and context based on task progression, and correspondingly adapt their strategy and toolbox, transforming from passive executors into dual managers of both task and self. We further devise Configuration-Aware Two-stage Training (CAT), combining rejection sampling fine-tuning with trajectory-level reinforcement learning to internalize this meta-capability. Extensive experiments across diverse benchmarks demonstrate that ToolSelf rivals specialized workflows while generalizing to novel tasks, achieving a 24.1% average performance gain and illuminating a path toward truly self-adaptive agents.
[551] MemFly: On-the-Fly Memory Optimization via Information Bottleneck
Zhenyuan Zhang, Xianzhang Jia, Zhiqin Yang, Zhenbo Song, Wei Xue, Sirui Han, Yike Guo
Main category: cs.AI
TL;DR: MemFly is a memory framework for LLM agents that balances compression efficiency with precise retrieval using information bottleneck principles and hybrid retrieval mechanisms.
Details
Motivation: Existing memory frameworks for LLM agents face a dilemma between compressing redundant information efficiently and maintaining precise retrieval for downstream tasks, limiting their effectiveness in complex scenarios.Method: Proposes MemFly framework based on information bottleneck principles with gradient-free optimization to minimize compression entropy while maximizing relevance entropy, creating stratified memory structure. Includes hybrid retrieval mechanism combining semantic, symbolic, and topological pathways with iterative refinement for complex queries.
Result: Comprehensive experiments show MemFly substantially outperforms state-of-the-art baselines in memory coherence, response fidelity, and accuracy.
Conclusion: MemFly successfully bridges the gap between efficient compression and precise retrieval for LLM agents through information bottleneck principles and hybrid retrieval mechanisms.
Abstract: Long-term memory enables large language model agents to tackle complex tasks through historical interactions. However, existing frameworks encounter a fundamental dilemma between compressing redundant information efficiently and maintaining precise retrieval for downstream tasks. To bridge this gap, we propose MemFly, a framework grounded in information bottleneck principles that facilitates on-the-fly memory evolution for LLMs. Our approach minimizes compression entropy while maximizing relevance entropy via a gradient-free optimizer, constructing a stratified memory structure for efficient storage. To fully leverage MemFly, we develop a hybrid retrieval mechanism that seamlessly integrates semantic, symbolic, and topological pathways, incorporating iterative refinement to handle complex multi-hop queries. Comprehensive experiments demonstrate that MemFly substantially outperforms state-of-the-art baselines in memory coherence, response fidelity, and accuracy.
[552] GCN-MPPR: Enhancing the Propagation of Message Passing Neural Networks via Motif-Based Personalized PageRank
Mingcan Wang, Junchang Xin, Zhongming Yao, Kaifu Long, Zhiqiong Wang
Main category: cs.AI
TL;DR: A novel motif-based personalized PageRank (MPPR) method is proposed to enhance graph convolutional networks by incorporating higher-order motif relationships during message passing, addressing limitations of shallow MPNNs.
Details
Motivation: Existing message passing neural networks (MPNNs) on graphs suffer from shallow propagation depth due to over-smoothing, limited accuracy, poor stability, and high computational cost. They also neglect higher-order relationships during propagation, which further limits performance.Method: Proposes motif-based personalized PageRank (MPPR) to measure node influence considering higher-order motif relationships. MPPR is then integrated into GCNs’ message passing process to guide propagation at a higher level, enabling deeper and more effective information flow.
Result: The proposed method outperforms almost all baselines on accuracy, stability, and time consumption. It can serve as a foundational component for various GCN tasks, as demonstrated with DGCRL in experiments.
Conclusion: MPPR effectively addresses the shallow depth problem in MPNNs by incorporating higher-order motif relationships, resulting in improved performance across multiple metrics while maintaining computational efficiency.
Abstract: The algorithms based on message passing neural networks (MPNNs) on graphs have recently achieved great success for various graph applications. However, studies find that these methods always propagate the information to very limited neighborhoods with shallow depth, particularly due to over-smoothing. That means most of the existing MPNNs fail to be so deep'. Although some previous work tended to handle this challenge via optimization- or structure-level remedies, the overall performance of GCNs still suffers from limited accuracy, poor stability, and unaffordable computational cost. Moreover, neglect of higher-order relationships during the propagation of MPNNs has further limited the performance of them. To overcome these challenges, a novel variant of PageRank named motif-based personalized PageRank (MPPR) is proposed to measure the influence of one node to another on the basis of considering higher-order motif relationships. Secondly, the MPPR is utilized to the message passing process of GCNs, thereby guiding the message passing process at a relatively high’ level. The experimental results show that the proposed method outperforms almost all of the baselines on accuracy, stability, and time consumption. Additionally, the proposed method can be considered as a component that can underpin almost all GCN tasks, with DGCRL being demonstrated in the experiment. The anonymous code repository is available at: https://anonymous.4open.science/r/GCN-MPPR-AFD6/.
[553] MedCoG: Maximizing LLM Inference Density in Medical Reasoning via Meta-Cognitive Regulation
Yu Zhao, Hao Guan, Yongcheng Jing, Ying Zhang, Dacheng Tao
Main category: cs.AI
TL;DR: MedCoG: A medical meta-cognition agent that uses LLM self-awareness to dynamically regulate knowledge utilization, improving inference efficiency by 5.5x on medical benchmarks.
Details
Motivation: LLMs show strong medical reasoning potential but face diminishing gains under inference scaling laws. Current approaches augment LLMs with various knowledge types, but it's unclear how effectively additional costs translate to accuracy improvements.Method: Proposes MedCoG, a Medical Meta-Cognition Agent with Knowledge Graph, where meta-cognitive assessments (task complexity, familiarity, knowledge density) dynamically regulate utilization of procedural, episodic, and factual knowledge. Uses LLM-centric on-demand reasoning to mitigate scaling laws by reducing costs via avoiding indiscriminate scaling and improving accuracy via filtering distractive knowledge.
Result: Experiments on five hard sets of medical benchmarks demonstrate effectiveness and efficiency, yielding 5.5x inference density (ratio of theoretically effective cost to actual cost). Oracle study highlights significant potential of meta-cognitive regulation.
Conclusion: Meta-cognition in LLMs can effectively regulate reasoning processes, improving both efficiency and accuracy in medical reasoning tasks by dynamically controlling knowledge utilization based on self-awareness of knowledge states.
Abstract: Large Language Models (LLMs) have shown strong potential in complex medical reasoning yet face diminishing gains under inference scaling laws. While existing studies augment LLMs with various knowledge types, it remains unclear how effectively the additional costs translate into accuracy. In this paper, we explore how meta-cognition of LLMs, i.e., their self-awareness of their own knowledge states, can regulate the reasoning process. Specifically, we propose MedCoG, a Medical Meta-Cognition Agent with Knowledge Graph, where the meta-cognitive assessments of task complexity, familiarity, and knowledge density dynamically regulate utilization of procedural, episodic, and factual knowledge. The LLM-centric on-demand reasoning aims to mitigate scaling laws by (1) reducing costs via avoiding indiscriminate scaling, (2) improving accuracy via filtering out distractive knowledge. To validate this, we empirically characterize the scaling curve and introduce inference density to quantify inference efficiency, defined as the ratio of theoretically effective cost to actual cost. Experiments demonstrate the effectiveness and efficiency of MedCoG on five hard sets of medical benchmarks, yielding 5.5x inference density. Furthermore, the Oracle study highlights the significant potential of meta-cognitive regulation.
[554] Selective Fine-Tuning for Targeted and Robust Concept Unlearning
Mansi, Avinash Kori, Francesca Toni, Soteris Demetriou
Main category: cs.AI
TL;DR: TRUST is a novel selective fine-tuning method for diffusion models that dynamically identifies and unlearns harmful concept neurons using Hessian-based regularization, enabling efficient unlearning of individual and combined concepts while preserving generation quality.
Details
Motivation: Current concept unlearning methods for text-guided diffusion models are computationally expensive (require full fine-tuning) and struggle with realistic concept combinations. Existing concept localization techniques are static and suboptimal, creating a need for more efficient and dynamic unlearning approaches.Method: TRUST dynamically estimates target concept neurons through selective fine-tuning empowered by Hessian-based regularization. It identifies specific neurons responsible for harmful concepts and selectively unlearns them rather than performing full model fine-tuning.
Result: TRUST outperforms state-of-the-art baselines in robustness against adversarial prompts, preserves generation quality significantly, and is much faster than existing methods. It successfully unlearns individual concepts, concept combinations, and conditional concepts without specific regularization.
Conclusion: TRUST provides an efficient and effective solution for concept unlearning in diffusion models, addressing computational limitations while maintaining robustness and generation quality for both individual and combined harmful concepts.
Abstract: Text guided diffusion models are used by millions of users, but can be easily exploited to produce harmful content. Concept unlearning methods aim at reducing the models’ likelihood of generating harmful content. Traditionally, this has been tackled at an individual concept level, with only a handful of recent works considering more realistic concept combinations. However, state of the art methods depend on full finetuning, which is computationally expensive. Concept localisation methods can facilitate selective finetuning, but existing techniques are static, resulting in suboptimal utility. In order to tackle these challenges, we propose TRUST (Targeted Robust Selective fine Tuning), a novel approach for dynamically estimating target concept neurons and unlearning them through selective finetuning, empowered by a Hessian based regularization. We show experimentally, against a number of SOTA baselines, that TRUST is robust against adversarial prompts, preserves generation quality to a significant degree, and is also significantly faster than the SOTA. Our method achieves unlearning of not only individual concepts but also combinations of concepts and conditional concepts, without any specific regularization.
[555] MePo: Meta Post-Refinement for Rehearsal-Free General Continual Learnin
Guanglong Sun, Hongwei Yan, Liyuan Wang, Zhiqi Kang, Shuang Cui, Hang Su, Jun Zhu, Yi Zhong
Main category: cs.AI
TL;DR: MePo is a meta-learning approach that refines pretrained models for general continual learning by using pseudo task sequences and meta covariance matrices to enable rapid adaptation to evolving data streams.
Details
Motivation: Current continual learning methods using pretrained models struggle with diverse, temporally mixed information in real-world scenarios with online datastreams and blurry task boundaries, leading to suboptimal performance in general continual learning.Method: MePo constructs pseudo task sequences from pretraining data and uses bi-level meta-learning to refine pretrained backbones. It initializes a meta covariance matrix as reference geometry for pretrained representation space, enabling second-order statistics for robust output alignment.
Result: MePo achieves significant performance gains across various GCL benchmarks (15.10% on CIFAR-100, 13.36% on ImageNet-R, 12.56% on CUB-200 under Sup-21/1K) in a rehearsal-free manner with different pretrained checkpoints.
Conclusion: MePo provides an effective plug-in strategy for pretrained models in general continual learning, enabling better adaptation to evolving environments through meta-learning and second-order statistics.
Abstract: To cope with uncertain changes of the external world, intelligent systems must continually learn from complex, evolving environments and respond in real time. This ability, collectively known as general continual learning (GCL), encapsulates practical challenges such as online datastreams and blurry task boundaries. Although leveraging pretrained models (PTMs) has greatly advanced conventional continual learning (CL), these methods remain limited in reconciling the diverse and temporally mixed information along a single pass, resulting in sub-optimal GCL performance. Inspired by meta-plasticity and reconstructive memory in neuroscience, we introduce here an innovative approach named Meta Post-Refinement (MePo) for PTMs-based GCL. This approach constructs pseudo task sequences from pretraining data and develops a bi-level meta-learning paradigm to refine the pretrained backbone, which serves as a prolonged pretraining phase but greatly facilitates rapid adaptation of representation learning to downstream GCL tasks. MePo further initializes a meta covariance matrix as the reference geometry of pretrained representation space, enabling GCL to exploit second-order statistics for robust output alignment. MePo serves as a plug-in strategy that achieves significant performance gains across a variety of GCL benchmarks and pretrained checkpoints in a rehearsal-free manner (e.g., 15.10%, 13.36%, and 12.56% on CIFAR-100, ImageNet-R, and CUB-200 under Sup-21/1K). Our source code is available at \href{https://github.com/SunGL001/MePo}{MePo}
[556] IV Co-Scientist: Multi-Agent LLM Framework for Causal Instrumental Variable Discovery
Ivaxi Sheth, Zhijing Jin, Bryan Wilder, Dominik Janzing, Mario Fritz
Main category: cs.AI
TL;DR: LLMs can help identify valid instrumental variables for causal inference by recovering established instruments and avoiding discredited ones, with a multi-agent system called IV Co-Scientist showing promise.
Details
Motivation: Identifying valid instrumental variables (IVs) for causal inference requires interdisciplinary knowledge and contextual understanding, which is challenging. The paper investigates whether LLMs can assist in this task by leveraging their knowledge and reasoning capabilities.Method: Two-stage evaluation: first testing if LLMs can recover well-established instruments from literature, then evaluating if they can identify and avoid empirically/theoretically discredited instruments. Introduces IV Co-Scientist, a multi-agent system that proposes, critiques, and refines IVs for treatment-outcome pairs, plus a statistical test for consistency without ground truth.
Result: LLMs show potential to discover valid instrumental variables from large observational databases, demonstrating ability to replicate standard reasoning and avoid invalid instruments.
Conclusion: LLMs can be valuable tools for instrumental variable discovery in causal inference, with the proposed IV Co-Scientist system offering a promising approach for automating and improving this challenging task.
Abstract: In the presence of confounding between an endogenous variable and the outcome, instrumental variables (IVs) are used to isolate the causal effect of the endogenous variable. Identifying valid instruments requires interdisciplinary knowledge, creativity, and contextual understanding, making it a non-trivial task. In this paper, we investigate whether large language models (LLMs) can aid in this task. We perform a two-stage evaluation framework. First, we test whether LLMs can recover well-established instruments from the literature, assessing their ability to replicate standard reasoning. Second, we evaluate whether LLMs can identify and avoid instruments that have been empirically or theoretically discredited. Building on these results, we introduce IV Co-Scientist, a multi-agent system that proposes, critiques, and refines IVs for a given treatment-outcome pair. We also introduce a statistical test to contextualize consistency in the absence of ground truth. Our results show the potential of LLMs to discover valid instrumental variables from a large observational database.
[557] LOCA-bench: Benchmarking Language Agents Under Controllable and Extreme Context Growth
Weihao Zeng, Yuzhen Huang, Junxian He
Main category: cs.AI
TL;DR: LOCA-bench is a benchmark for evaluating language agents in long-context scenarios with dynamically growing contexts, addressing context rot in LLMs for real-world agentic tasks.
Details
Motivation: Current long-context benchmarks focus on single-step information retrieval, but real-world LLM agents need to explore environments, follow instructions, extract information, and predict actions under dynamically growing contexts. The "context rot" phenomenon causes reliability deterioration as context grows.Method: LOCA-bench uses automated and scalable control of environment states to regulate agent context length. It can extend context length potentially to infinity while keeping task semantics fixed, evaluating language agents as combinations of models and scaffolds with various context management strategies.
Result: Agent performance generally degrades as environment states grow more complex, but advanced context management techniques can substantially improve overall success rates. The benchmark provides a platform for evaluating models and scaffolds in long-context, agentic scenarios.
Conclusion: LOCA-bench addresses the gap in evaluating LLM agents in realistic long-context scenarios and demonstrates that proper context management strategies can mitigate context rot in agentic settings.
Abstract: Large language models (LLMs) are increasingly capable of carrying out long-running, real-world tasks. However, as the amount of context grows, their reliability often deteriorates, a phenomenon known as “context rot”. Existing long-context benchmarks primarily focus on single-step settings that evaluate a model’s ability to retrieve information from a long snippet. In realistic scenarios, however, LLMs often need to act as agents that explore environments, follow instructions and plans, extract useful information, and predict correct actions under a dynamically growing context. To assess language agents in such settings, we introduce LOCA-bench (a benchmark for LOng-Context Agents). Given a task prompt, LOCA-bench leverages automated and scalable control of environment states to regulate the agent’s context length. This design enables LOCA-bench to extend the context length potentially to infinity in a controlled way while keeping the underlying task semantics fixed. LOCA-bench evaluates language agents as a combination of models and scaffolds, including various context management strategies. While agent performance generally degrades as the environment states grow more complex, advanced context management techniques can substantially improve the overall success rate. We open-source LOCA-bench to provide a platform for evaluating models and scaffolds in long-context, agentic scenarios: https://github.com/hkust-nlp/LOCA-bench
[558] Accelerating Social Science Research via Agentic Hypothesization and Experimentation
Jishu Sen Gupta, Harini SI, Somesh Kumar Singh, Syed Mohamad Tawseeq, Yaman Kumar Singla, David Doermann, Rajiv Ratn Shah, Balaji Krishnamurthy
Main category: cs.AI
TL;DR: EXPERIGEN is an agentic framework for end-to-end scientific discovery using a two-phase Bayesian optimization approach with Generator and Experimenter agents to propose and evaluate hypotheses across domains including multimodal data.
Details
Motivation: Current data-driven methods in social science research are slow and fail to support complete end-to-end scientific discovery cycles. There's a need for frameworks that can accelerate the entire process from hypothesis generation to experimental validation.Method: EXPERIGEN uses a Bayesian optimization inspired two-phase search: a Generator agent proposes candidate hypotheses, and an Experimenter agent evaluates them empirically. The framework extends to complex data regimes including multimodal and relational datasets.
Result: EXPERIGEN discovers 2-4x more statistically significant hypotheses that are 7-17% more predictive than prior approaches. Expert review shows 88% of hypotheses rated moderately/strongly novel, 70% deemed impactful. First A/B test of LLM-generated hypotheses shows p < 1e-6 with 344% effect size.
Conclusion: EXPERIGEN successfully operationalizes end-to-end scientific discovery, demonstrating superior statistical performance, novelty, and real-world impact across multiple domains including multimodal data regimes.
Abstract: Data-driven social science research is inherently slow, relying on iterative cycles of observation, hypothesis generation, and experimental validation. While recent data-driven methods promise to accelerate parts of this process, they largely fail to support end-to-end scientific discovery. To address this gap, we introduce EXPERIGEN, an agentic framework that operationalizes end-to-end discovery through a Bayesian optimization inspired two-phase search, in which a Generator proposes candidate hypotheses and an Experimenter evaluates them empirically. Across multiple domains, EXPERIGEN consistently discovers 2-4x more statistically significant hypotheses that are 7-17 percent more predictive than prior approaches, and naturally extends to complex data regimes including multimodal and relational datasets. Beyond statistical performance, hypotheses must be novel, empirically grounded, and actionable to drive real scientific progress. To evaluate these qualities, we conduct an expert review of machine-generated hypotheses, collecting feedback from senior faculty. Among 25 reviewed hypotheses, 88 percent were rated moderately or strongly novel, 70 percent were deemed impactful and worth pursuing, and most demonstrated rigor comparable to senior graduate-level research. Finally, recognizing that ultimate validation requires real-world evidence, we conduct the first A/B test of LLM-generated hypotheses, observing statistically significant results with p less than 1e-6 and a large effect size of 344 percent.
[559] Towards Adaptive, Scalable, and Robust Coordination of LLM Agents: A Dynamic Ad-Hoc Networking Perspective
Rui Li, Zeyu Zhang, Xiaohe Bo, Quanyu Dai, Chaozhuo Li, Feng Wen, Xu Chen
Main category: cs.AI
TL;DR: RAPS introduces a reputation-aware publish-subscribe paradigm for adaptive, scalable, and robust coordination of LLM agents using dynamic intent-based communication and Bayesian reputation systems.
Details
Motivation: Multi-agent LLM systems require manual orchestration, creating a need to automate agentic workflow design. The paper frames this as a dynamic ad-hoc networking problem: how to establish adaptive and reliable communication among scalable numbers of agentic hosts.Method: RAPS uses Distributed Publish-Subscribe Protocol for intent-based message exchange, plus two overlays: Reactive Subscription for dynamic intent refinement, and Bayesian Reputation for local malicious peer detection and isolation.
Result: Extensive experiments over five benchmarks show the design effectively reconciles adaptivity, scalability, and robustness in a unified multi-agent coordination framework.
Conclusion: RAPS provides an automated solution for LLM agent coordination that addresses the challenges of adaptivity, scalability, and robustness through reputation-aware publish-subscribe mechanisms.
Abstract: Multi-agent architectures built on large language models (LLMs) have demonstrated the potential to realize swarm intelligence through well-crafted collaboration. However, the substantial burden of manual orchestration inherently raises an imperative to automate the design of agentic workflows. We frame such an agent coordination challenge as a classic problem in dynamic ad-hoc networking: How to establish adaptive and reliable communication among a scalable number of agentic hosts? In response to this unresolved dilemma, we introduce RAPS, a reputation-aware publish-subscribe paradigm for adaptive, scalable, and robust coordination of LLM agents. RAPS is grounded in the Distributed Publish-Subscribe Protocol, allowing LLM agents to exchange messages based on their declared intents rather than predefined topologies. Beyond this substrate, RAPS further incorporates two coherent overlays: (i) Reactive Subscription, enabling agents to dynamically refine their intents; and (ii) Bayesian Reputation, empowering each agent with a local watchdog to detect and isolate malicious peers. Extensive experiments over five benchmarks showcase that our design effectively reconciles adaptivity, scalability, and robustness in a unified multi-agent coordination framework.
[560] Small Agent Group is the Future of Digital Health
Yuqiao Meng, Luoxi Tang, Dazheng Zhang, Rafael Brens, Elvys J. Romero, Nancy Guo, Safa Elkefi, Zhaohan Xi
Main category: cs.AI
TL;DR: Small Agent Groups (SAG) outperform single large models in clinical reasoning by distributing tasks through collaborative deliberation, offering better effectiveness, reliability, and deployment efficiency.
Details
Motivation: Current LLM adoption in digital health follows a "scaling-first" philosophy assuming bigger models are better, but real-world clinical needs require reliability and reasonable deployment costs. Clinical decision-making is inherently collaborative, so the authors question whether multiple smaller models working together could outperform single large models.Method: Proposes Small Agent Group (SAG) approach that shifts from single-model intelligence to collective expertise by distributing reasoning, evidence-based analysis, and critical audit through collaborative deliberation processes. Evaluated using diverse clinical metrics spanning effectiveness, reliability, and deployment cost.
Result: SAG achieves superior performance compared to single giant models, both with and without additional optimization or retrieval-augmented generation. The synergistic reasoning of SAG can substitute for model parameter growth in clinical settings.
Conclusion: SAG offers a scalable solution to digital health that better balances effectiveness, reliability, and deployment efficiency, challenging the monolithic scaling paradigm with collaborative multi-agent approaches.
Abstract: The rapid adoption of large language models (LLMs) in digital health has been driven by a “scaling-first” philosophy, i.e., the assumption that clinical intelligence increases with model size and data. However, real-world clinical needs include not only effectiveness, but also reliability and reasonable deployment cost. Since clinical decision-making is inherently collaborative, we challenge the monolithic scaling paradigm and ask whether a Small Agent Group (SAG) can support better clinical reasoning. SAG shifts from single-model intelligence to collective expertise by distributing reasoning, evidence-based analysis, and critical audit through a collaborative deliberation process. To assess the clinical utility of SAG, we conduct extensive evaluations using diverse clinical metrics spanning effectiveness, reliability, and deployment cost. Our results show that SAG achieves superior performance compared to a single giant model, both with and without additional optimization or retrieval-augmented generation. These findings suggest that the synergistic reasoning represented by SAG can substitute for model parameter growth in clinical settings. Overall, SAG offers a scalable solution to digital health that better balances effectiveness, reliability, and deployment efficiency.
[561] Structure-Aware Robust Counterfactual Explanations via Conditional Gaussian Network Classifiers
Zhan-Yi Liao, Jaewon Yoo, Hao-Tsung Yang, Po-An Chen
Main category: cs.AI
TL;DR: A structure-aware counterfactual explanation method using conditional Gaussian network classifiers with convergence-guaranteed adversarial optimization for robust explanations.
Details
Motivation: Counterfactual explanations are crucial for XAI to interpret model decisions, but existing methods often lack robustness and don't incorporate feature dependencies. The paper aims to develop a method that naturally embeds structural relationships between features while ensuring robust explanations.Method: Uses conditional Gaussian network classifier (CGNC) with directed acyclic graph to encode feature dependencies. Employs convergence-guaranteed cutting-set procedure for adversarial optimization, and applies piecewise McCormick relaxation to reformulate nonconvex quadratic problems as mixed-integer linear programs for global optimality.
Result: The method achieves strong robustness with direct global optimization providing stable and efficient results. The framework shows extensibility to complex constraint settings.
Conclusion: The proposed structure-aware counterfactual search method successfully incorporates feature dependencies through CGNC’s generative structure and ensures robustness through convergence-guaranteed optimization, providing a foundation for future advances in counterfactual reasoning under nonconvex quadratic formulations.
Abstract: Counterfactual explanation (CE) is a core technique in explainable artificial intelligence (XAI), widely used to interpret model decisions and suggest actionable alternatives. This work presents a structure-aware and robustness-oriented counterfactual search method based on the conditional Gaussian network classifier (CGNC). The CGNC has a generative structure that encodes conditional dependencies and potential causal relations among features through a directed acyclic graph (DAG). This structure naturally embeds feature relationships into the search process, eliminating the need for additional constraints to ensure consistency with the model’s structural assumptions. We adopt a convergence-guaranteed cutting-set procedure as an adversarial optimization framework, which iteratively approximates solutions that satisfy global robustness conditions. To address the nonconvex quadratic structure induced by feature dependencies, we apply piecewise McCormick relaxation to reformulate the problem as a mixed-integer linear program (MILP), ensuring global optimality. Experimental results show that our method achieves strong robustness, with direct global optimization of the original formulation providing especially stable and efficient results. The proposed framework is extensible to more complex constraint settings, laying the groundwork for future advances in counterfactual reasoning under nonconvex quadratic formulations.
[562] Free(): Learning to Forget in Malloc-Only Reasoning Models
Yilun Zheng, Dongyang Ma, Tian Liang, Jiahao Xu, Xinting Huang, Lijie Chen, Haitao Mi, Yan Wang
Main category: cs.AI
TL;DR: Free()LM introduces self-forgetting capability to LLMs via a plug-and-play LoRA adapter that dynamically prunes useless context during reasoning, preventing performance degradation from excessive thinking tokens.
Details
Motivation: Standard reasoning models suffer from performance degradation when using excessive thinking tokens due to continuous accumulation of both valid and redundant information without pruning mechanisms, creating a "malloc-only" architecture flaw.Method: Free()LM uses a Free-Module (plug-and-play LoRA adapter) that enables iterative switching between reasoning and cleaning modes to dynamically identify and prune useless context chunks, maintaining compact and noise-free reasoning states.
Result: Free()LM achieves 3.3% average improvement over top-tier reasoning baselines across model scales (8B to 685B), establishes new SOTA on IMOanswerBench, and restores performance from 0% to 50% in long-horizon tasks where standard models collapse.
Conclusion: Sustainable intelligence requires both the power to think and the freedom to forget; self-forgetting mechanisms are essential for preventing reasoning degradation in LLMs.
Abstract: Reasoning models enhance problem-solving by scaling test-time compute, yet they face a critical paradox: excessive thinking tokens often degrade performance rather than improve it. We attribute this to a fundamental architectural flaw: standard LLMs operate as “malloc-only” engines, continuously accumulating valid and redundant steps alike without a mechanism to prune obsolete information. To break this cycle, we propose Free()LM, a model that introduces an intrinsic self-forgetting capability via the Free-Module, a plug-and-play LoRA adapter. By iteratively switching between reasoning and cleaning modes, Free()LM dynamically identifies and prunes useless context chunks, maintaining a compact and noise-free state. Extensive experiments show that Free()LM provides consistent improvements across all model scales (8B to 685B). It achieves a 3.3% average improvement over top-tier reasoning baselines, even establishing a new SOTA on IMOanswerBench using DeepSeek V3.2-Speciale. Most notably, in long-horizon tasks where the standard Qwen3-235B-A22B model suffers a total collapse (0% accuracy), Free()LM restores performance to 50%. Our findings suggest that sustainable intelligence requires the freedom to forget as much as the power to think.
[563] Graph-Enhanced Deep Reinforcement Learning for Multi-Objective Unrelated Parallel Machine Scheduling
Bulent Soykan, Sean Mondesire, Ghaith Rabadi, Grace Bochenek
Main category: cs.AI
TL;DR: Deep Reinforcement Learning with PPO and GNN for multi-objective unrelated parallel machine scheduling with release dates, setups, and eligibility constraints.
Details
Motivation: Traditional methods struggle to balance minimizing Total Weighted Tardiness (TWT) and Total Setup Time (TST) in complex manufacturing scheduling problems with multiple constraints.Method: Proposes a Deep Reinforcement Learning framework using Proximal Policy Optimization (PPO) and Graph Neural Network (GNN) to represent complex state of jobs, machines, and setups, learning a direct scheduling policy guided by multi-objective reward function.
Result: PPO-GNN agent significantly outperforms standard dispatching rule and metaheuristic, achieving superior trade-off between minimizing TWT and TST on benchmark instances.
Conclusion: Provides a robust and scalable solution for complex manufacturing scheduling problems using deep reinforcement learning with graph neural networks.
Abstract: The Unrelated Parallel Machine Scheduling Problem (UPMSP) with release dates, setups, and eligibility constraints presents a significant multi-objective challenge. Traditional methods struggle to balance minimizing Total Weighted Tardiness (TWT) and Total Setup Time (TST). This paper proposes a Deep Reinforcement Learning framework using Proximal Policy Optimization (PPO) and a Graph Neural Network (GNN). The GNN effectively represents the complex state of jobs, machines, and setups, allowing the PPO agent to learn a direct scheduling policy. Guided by a multi-objective reward function, the agent simultaneously minimizes TWT and TST. Experimental results on benchmark instances demonstrate that our PPO-GNN agent significantly outperforms a standard dispatching rule and a metaheuristic, achieving a superior trade-off between both objectives. This provides a robust and scalable solution for complex manufacturing scheduling.
[564] Securing Dual-Use Pathogen Data of Concern
Doni Bloomfield, Allison Berke, Moritz S. Hanke, Aaron Maiwald, James R. M. Black, Toby Webster, Tina Hernandez-Boussard, Oliver M. Crook, Jassi Pannu
Main category: cs.AI
TL;DR: A framework for categorizing pathogen data into five biosecurity risk levels with corresponding technical restrictions to prevent AI models from being trained on data that could enable bioweapons development.
Details
Motivation: To address biosecurity concerns in AI development for biology by creating data controls that prevent AI models from acquiring harmful capabilities through training on sensitive pathogen data, following international researcher consensus at the Asilomar Conference.Method: Developed a five-tier Biosecurity Data Level (BDL) framework that categorizes pathogen data types based on their potential to contribute to concerning AI capabilities, with technical restrictions proposed for each risk level and a governance framework for dual-use pathogen data.
Result: A comprehensive biosecurity framework that links specific data types to AI risk levels, providing a structured approach to data control that could serve as a high-leverage intervention in preventing proliferation of dangerous biological AI capabilities.
Conclusion: In an era of widely accessible computational resources, data controls represent a crucial intervention point for reducing risks from AI models trained on biological data, with the proposed BDL framework offering a practical approach to implementing such controls.
Abstract: Training data is an essential input into creating competent artificial intelligence (AI) models. AI models for biology are trained on large volumes of data, including data related to biological sequences, structures, images, and functions. The type of data used to train a model is intimately tied to the capabilities it ultimately possesses–including those of biosecurity concern. For this reason, an international group of more than 100 researchers at the recent 50th anniversary Asilomar Conference endorsed data controls to prevent the use of AI for harmful applications such as bioweapons development. To help design such controls, we introduce a five-tier Biosecurity Data Level (BDL) framework for categorizing pathogen data. Each level contains specific data types, based on their expected ability to contribute to capabilities of concern when used to train AI models. For each BDL tier, we propose technical restrictions appropriate to its level of risk. Finally, we outline a novel governance framework for newly created dual-use pathogen data. In a world with widely accessible computational and coding resources, data controls may be among the most high-leverage interventions available to reduce the proliferation of concerning biological AI capabilities.
[565] Objective Decoupling in Social Reinforcement Learning: Recovering Ground Truth from Sycophantic Majorities
Majid Ghasemi, Mark Crowley
Main category: cs.AI
TL;DR: Paper challenges assumption that human feedback is fundamentally truthful in RL alignment, showing it fails in social settings with biased evaluators, and proposes Epistemic Source Alignment to judge feedback sources rather than signals.
Details
Motivation: The paper identifies a critical flaw in current AI alignment strategies: the assumption that human feedback, while noisy, remains fundamentally truthful (Dogma 4 of RL). The authors argue this assumption fails in social settings where evaluators can be sycophantic, lazy, or adversarial, leading to permanent misalignment.Method: The authors propose Epistemic Source Alignment (ESA), which differs from standard robust methods that rely on statistical consensus. ESA uses sparse safety axioms to judge the source of feedback rather than the signal itself - a “judging the judges” mechanism that evaluates feedback providers rather than aggregating their signals.
Result: The paper proves that under Dogma 4, standard RL agents suffer from Objective Decoupling where learned objectives permanently separate from ground truth. They prove ESA guarantees convergence to true objectives even with majority biased evaluators. Empirically, traditional consensus methods fail under majority collusion while ESA recovers optimal policies.
Conclusion: The fundamental assumption of truthful human feedback in RL alignment is flawed in social contexts. Epistemic Source Alignment provides a solution by evaluating feedback sources rather than signals, enabling robust alignment even with biased evaluators.
Abstract: Contemporary AI alignment strategies rely on a fragile premise: that human feedback, while noisy, remains a fundamentally truthful signal. In this paper, we identify this assumption as Dogma 4 of Reinforcement Learning (RL). We demonstrate that while this dogma holds in static environments, it fails in social settings where evaluators may be sycophantic, lazy, or adversarial. We prove that under Dogma 4, standard RL agents suffer from what we call Objective Decoupling, a structural failure mode where the agent’s learned objective permanently separates from the latent ground truth, guaranteeing convergence to misalignment. To resolve this, we propose Epistemic Source Alignment (ESA). Unlike standard robust methods that rely on statistical consensus (trusting the majority), ESA utilizes sparse safety axioms to judge the source of the feedback rather than the signal itself. We prove that this “judging the judges” mechanism guarantees convergence to the true objective, even when a majority of evaluators are biased. Empirically, we show that while traditional consensus methods fail under majority collusion, our approach successfully recovers the optimal policy.
[566] Initial Risk Probing and Feasibility Testing of Glow: a Generative AI-Powered Dialectical Behavior Therapy Skills Coach for Substance Use Recovery and HIV Prevention
Liying Wang, Madison Lee, Yunzhang Jiang, Steven Chen, Kewei Sha, Yunhe Feng, Frank Wong, Lisa Hightow-Weidman, Weichao Yuwen
Main category: cs.AI
TL;DR: GenAI-powered DBT coach for HIV/substance use risk shows safety vulnerabilities in user testing, with 73% appropriate handling of risk probes but significant failures in some agents.
Details
Motivation: HIV and substance use epidemics share psychological drivers (impulsivity, maladaptive coping) that DBT targets, but DBT faces scalability challenges. GenAI offers potential for personalized DBT coaching at scale, but rapid development has outpaced safety infrastructure.Method: Developed Glow, a GenAI-powered DBT skills coach for chain and solution analysis. Conducted usability testing with clinical staff (n=6) and individuals with lived experience (n=28) using the HHH framework. Employed user-driven adversarial testing where participants identified target behaviors and generated contextually realistic risk probes, evaluating safety across 37 risk probe interactions.
Result: Glow appropriately handled 73% of risk probes, but performance varied significantly by agent: solution analysis agent demonstrated 90% appropriate handling vs 44% for chain analysis agent. Safety failures clustered around encouraging substance use and normalizing harmful behaviors. Chain analysis agent fell into “empathy trap” providing validation that reinforced maladaptive beliefs. Also identified 27 instances of DBT skill misinformation.
Conclusion: First systematic safety evaluation of GenAI-delivered DBT coaching for HIV/substance use risk reduction reveals vulnerabilities requiring mitigation before clinical trials. HHH framework and user-driven adversarial testing offer replicable methods for evaluating GenAI mental health interventions.
Abstract: Background: HIV and substance use represent interacting epidemics with shared psychological drivers - impulsivity and maladaptive coping. Dialectical behavior therapy (DBT) targets these mechanisms but faces scalability challenges. Generative artificial intelligence (GenAI) offers potential for delivering personalized DBT coaching at scale, yet rapid development has outpaced safety infrastructure. Methods: We developed Glow, a GenAI-powered DBT skills coach delivering chain and solution analysis for individuals at risk for HIV and substance use. In partnership with a Los Angeles community health organization, we conducted usability testing with clinical staff (n=6) and individuals with lived experience (n=28). Using the Helpful, Honest, and Harmless (HHH) framework, we employed user-driven adversarial testing wherein participants identified target behaviors and generated contextually realistic risk probes. We evaluated safety performance across 37 risk probe interactions. Results: Glow appropriately handled 73% of risk probes, but performance varied by agent. The solution analysis agent demonstrated 90% appropriate handling versus 44% for the chain analysis agent. Safety failures clustered around encouraging substance use and normalizing harmful behaviors. The chain analysis agent fell into an “empathy trap,” providing validation that reinforced maladaptive beliefs. Additionally, 27 instances of DBT skill misinformation were identified. Conclusions: This study provides the first systematic safety evaluation of GenAI-delivered DBT coaching for HIV and substance use risk reduction. Findings reveal vulnerabilities requiring mitigation before clinical trials. The HHH framework and user-driven adversarial testing offer replicable methods for evaluating GenAI mental health interventions.
[567] RECUR: Resource Exhaustion Attack via Recursive-Entropy Guided Counterfactual Utilization and Reflection
Ziwei Wang, Yuanhe Zhang, Jing Chen, Zhenhong Zhou, Ruichao Liang, Ruiying Du, Ju Jia, Cong Wu, Yang Liu
Main category: cs.AI
TL;DR: RECUR attack uses recursive entropy to quantify and exploit reflection vulnerabilities in Large Reasoning Models, causing up to 11x longer outputs and 90% throughput reduction through counterfactual questions.
Details
Motivation: Large Reasoning Models require extended context for explicit reasoning, consuming substantial resources. While adversarial inputs can trigger redundant reasoning, the reflection component itself has been overlooked despite its potential for over-reflection and excessive computing power consumption.Method: Introduces Recursive Entropy to quantify resource consumption risk in reflection, then develops RECUR (Resource Exhaustion attack via Recursive Entropy guided Counterfactual Utilization and Reflection) that constructs counterfactual questions to exploit LRM vulnerabilities.
Result: Under benign inference, recursive entropy shows decreasing trend. RECUR disrupts this trend, increasing output length by up to 11x and decreasing throughput by 90%, demonstrating significant resource exhaustion vulnerabilities.
Conclusion: The work reveals safety issues inherent in inference itself and provides a new perspective on robust reasoning by quantifying and exploiting reflection vulnerabilities in Large Reasoning Models.
Abstract: Large Reasoning Models (LRMs) employ reasoning to address complex tasks. Such explicit reasoning requires extended context lengths, resulting in substantially higher resource consumption. Prior work has shown that adversarially crafted inputs can trigger redundant reasoning processes, exposing LRMs to resource-exhaustion vulnerabilities. However, the reasoning process itself, especially its reflective component, has received limited attention, even though it can lead to over-reflection and consume excessive computing power. In this paper, we introduce Recursive Entropy to quantify the risk of resource consumption in reflection, thereby revealing the safety issues inherent in inference itself. Based on Recursive Entropy, we introduce RECUR, a resource exhaustion attack via Recursive Entropy guided Counterfactual Utilization and Reflection. It constructs counterfactual questions to verify the inherent flaws and risks of LRMs. Extensive experiments demonstrate that, under benign inference, recursive entropy exhibits a pronounced decreasing trend. RECUR disrupts this trend, increasing the output length by up to 11x and decreasing throughput by 90%. Our work provides a new perspective on robust reasoning.
[568] Weak-Driven Learning: How Weak Agents make Strong Agents Stronger
Zehao Chen, Gongxun Li, Tianxiang Ai, Yifei Li, Zixuan Huang, Wang Zhou, Fuzhen Zhuang, Xianglong Liu, Jianxin Li, Deqing Wang, Yikun Ban
Main category: cs.AI
TL;DR: WMSS is a post-training method that uses weak historical checkpoints to guide optimization of strong models beyond saturation by identifying learning gaps through entropy dynamics and reinforcing them with compensatory learning.
Details
Motivation: Post-training optimization faces saturation bottlenecks where highly confident models show diminishing returns. The authors observe that informative supervision signals remain latent in models' own historical weak states, suggesting these can guide further improvement.Method: WMSS leverages weak checkpoints to guide continued optimization by: 1) identifying recoverable learning gaps via entropy dynamics analysis, and 2) reinforcing these gaps through compensatory learning, enabling strong agents to improve beyond conventional saturation.
Result: Experiments on mathematical reasoning and code generation datasets show that agents trained with WMSS achieve effective performance improvements while incurring zero additional inference cost.
Conclusion: WMSS provides a novel post-training paradigm that overcomes saturation bottlenecks by utilizing weak historical checkpoints to guide optimization, enabling continued improvement of strong models without inference overhead.
Abstract: As post-training optimization becomes central to improving large language models, we observe a persistent saturation bottleneck: once models grow highly confident, further training yields diminishing returns. While existing methods continue to reinforce target predictions, we find that informative supervision signals remain latent in models’ own historical weak states. Motivated by this observation, we propose WMSS (Weak Agents Can Make Strong Agents Stronger), a post-training paradigm that leverages weak checkpoints to guide continued optimization. By identifying recoverable learning gaps via entropy dynamics and reinforcing them through compensatory learning, WMSS enables strong agents to improve beyond conventional post-training saturation. Experiments on mathematical reasoning and code generation datasets show that agents trained with our approach achieve effective performance improvements, while incurring zero additional inference cost.
[569] InfiCoEvalChain: A Blockchain-Based Decentralized Framework for Collaborative LLM Evaluation
Yifan Yang, Jinjia Li, Kunxi Li, Puhao Zheng, Yuanyi Wang, Zheyan Qu, Yang Yu, Jianmin Wu, Ming Li, Hongxia Yang
Main category: cs.AI
TL;DR: A decentralized evaluation framework for LLMs using blockchain to address instability in current centralized evaluation methods, reducing variance through distributed validation across heterogeneous hardware.
Details
Motivation: Current LLM evaluation suffers from opacity, overfitting, and hardware-induced variance, with empirical analysis showing evaluation inconsistency where standard deviation across repeated runs exceeds performance gaps between top models, making rankings statistically unreliable.Method: Proposes a decentralized evaluation framework leveraging blockchain-based protocol to enable hardware and parameter diversity through large-scale benchmarking across heterogeneous compute nodes, incentivizing global contributors as independent validators with robust reward systems.
Result: The decentralized framework reduces standard deviation across ten runs on the same model from 1.67 to 0.28, significantly improving statistical confidence in model rankings compared to conventional frameworks.
Conclusion: Decentralized evaluation transforms evaluation from a “centralized black box” to “decentralized endorsement” with multi-party consensus and diverse inference environments, yielding more stable and representative metrics for LLM assessment.
Abstract: The rapid advancement of large language models (LLMs) demands increasingly reliable evaluation, yet current centralized evaluation suffers from opacity, overfitting, and hardware-induced variance. Our empirical analysis reveals an alarming inconsistency in existing evaluations: the standard deviation across ten repeated runs of a single model on HumanEval (1.67) actually exceeds the performance gap among the top-10 models on the official leaderboard (0.91), rendering current rankings statistically precarious. To mitigate these instabilities, we propose a decentralized evaluation framework that enables hardware and parameter diversity through large-scale benchmarking across heterogeneous compute nodes. By leveraging the blockchain-based protocol, the framework incentivizes global contributors to act as independent validators, using a robust reward system to ensure evaluation integrity and discourage dishonest participation. This collective verification transforms evaluation from a “centralized black box” into a “decentralized endorsement” where multi-party consensus and diverse inference environments yield a more stable, representative metric. Experimental results demonstrate that the decentralized evaluation framework reduces the standard deviation across ten runs on the same model to 0.28. This significant improvement over conventional frameworks ensures higher statistical confidence in model rankings. We have completely implemented this platform and will soon release it to the community.
[570] Do MLLMs Really See It: Reinforcing Visual Attention in Multimodal LLMs
Siqu Ou, Tianrui Wan, Zhiyuan Zhao, Junyu Gao, Xuelong Li
Main category: cs.AI
TL;DR: SAYO is a visual reasoning model using RL with region-level visual attention rewards to improve MLLMs’ visual focus and correct early-stage misalignments during reasoning.
Details
Motivation: Current MLLMs exhibit weak visual focus where early-stage visual misalignment is rarely corrected during reasoning, leading to error propagation. This stems from inadequate credit assignment for visual attention during training.Method: Proposes SAYO, a visual reasoning model trained with reinforcement learning framework that introduces region-level visual attention-based reward to explicitly align optimization signals with visually grounded reasoning steps.
Result: Extensive experiments across multiple multimodal benchmarks demonstrate that SAYO consistently improves performance on diverse reasoning and perception tasks.
Conclusion: The RL framework with region-level visual attention rewards enables MLLMs to learn more reliable attention behaviors and improve visual reasoning capabilities.
Abstract: While chain-of-thought (CoT) reasoning has substantially improved multimodal large language models (MLLMs) on complex reasoning tasks, existing approaches largely rely on long textual reasoning trajectories and provide limited mechanisms for learning stable visual attention policies. Our analysis shows that current MLLMs exhibit weak visual focus: early-stage visual misalignment is rarely corrected during subsequent reasoning, leading to error propagation and failed inferences. We argue that this limitation stems from inadequate credit assignment for visual attention during training. To address this issue, we propose SAYO, a visual reasoning model trained with a reinforcement learning (RL) framework that introduces a region-level visual attention-based reward. This reward explicitly aligns optimization signals with visually grounded reasoning steps, enabling the model to learn more reliable attention behaviors. Extensive experiments across multiple multimodal benchmarks demonstrate that SAYO consistently improves performance on diverse reasoning and perception tasks.
[571] G-LNS: Generative Large Neighborhood Search for LLM-Based Automatic Heuristic Design
Baoyun Zhao, He Wang, Liang Zeng
Main category: cs.AI
TL;DR: G-LNS is a generative evolutionary framework using LLMs to co-evolve destroy and repair operators for Large Neighborhood Search in combinatorial optimization, outperforming existing methods.
Details
Motivation: Existing LLM-based Automated Heuristic Design approaches are limited to fixed heuristic forms (constructive priority rules or parameterized local search guidance), restricting structural exploration and making it difficult to escape deep local optima in complex Combinatorial Optimization Problems.Method: Proposes G-LNS, a generative evolutionary framework that extends LLM-based AHD to automatically design Large Neighborhood Search operators. It leverages LLMs to co-evolve tightly coupled pairs of destroy and repair operators with a cooperative evaluation mechanism that captures their interaction.
Result: Extensive experiments on challenging COP benchmarks (Traveling Salesman Problems and Capacitated Vehicle Routing Problems) show G-LNS significantly outperforms LLM-based AHD methods and strong classical solvers. Discovered heuristics achieve near-optimal solutions with reduced computational budgets and exhibit robust generalization across diverse and unseen instance distributions.
Conclusion: G-LNS successfully extends LLM capabilities to automated design of Large Neighborhood Search operators, enabling discovery of complementary destroy-repair pairs that outperform existing approaches and demonstrate strong generalization.
Abstract: While Large Language Models (LLMs) have recently shown promise in Automated Heuristic Design (AHD), existing approaches typically formulate AHD around constructive priority rules or parameterized local search guidance, thereby restricting the search space to fixed heuristic forms. Such designs offer limited capacity for structural exploration, making it difficult to escape deep local optima in complex Combinatorial Optimization Problems (COPs). In this work, we propose G-LNS, a generative evolutionary framework that extends LLM-based AHD to the automated design of Large Neighborhood Search (LNS) operators. Unlike prior methods that evolve heuristics in isolation, G-LNS leverages LLMs to co-evolve tightly coupled pairs of destroy and repair operators. A cooperative evaluation mechanism explicitly captures their interaction, enabling the discovery of complementary operator logic that jointly performs effective structural disruption and reconstruction. Extensive experiments on challenging COP benchmarks, such as Traveling Salesman Problems (TSP) and Capacitated Vehicle Routing Problems (CVRP), demonstrate that G-LNS significantly outperforms LLM-based AHD methods as well as strong classical solvers. The discovered heuristics not only achieve near-optimal solutions with reduced computational budgets but also exhibit robust generalization across diverse and unseen instance distributions.
[572] Puda: Private User Dataset Agent for User-Sovereign and Privacy-Preserving Personalized AI
Akinori Maeda, Yuto Sekiya, Sota Sugimura, Tomoya Asai, Yu Tsuda, Kohei Ikeda, Hiroshi Fujii, Kohei Watanabe
Main category: cs.AI
TL;DR: Puda is a user-sovereign architecture for managing personal data across services with multi-granular privacy controls, enabling personalized LLM-based services while protecting privacy.
Details
Motivation: Current data centralization in platform ecosystems restricts user sovereignty and data portability, while LLM-based agents demand personalized data access, creating a privacy-personalization trade-off that needs balancing.Method: Proposes Puda (Private User Dataset Agent) - a browser-based system with three privacy levels: Detailed Browsing History, Extracted Keywords, and Predefined Category Subsets, enabling client-side data management and controlled sharing.
Result: In personalized travel planning tasks, Predefined Category Subsets achieved 97.2% of the personalization performance of Detailed Browsing History when evaluated via LLM-as-a-Judge framework across three criteria.
Conclusion: Puda enables effective multi-granularity privacy management, offering practical solutions to mitigate the privacy-personalization trade-off and providing an AI-native foundation for user sovereignty in personalized AI services.
Abstract: Personal data centralization among dominant platform providers including search engines, social networking services, and e-commerce has created siloed ecosystems that restrict user sovereignty, thereby impeding data use across services. Meanwhile, the rapid proliferation of Large Language Model (LLM)-based agents has intensified demand for highly personalized services that require the dynamic provision of diverse personal data. This presents a significant challenge: balancing the utilization of such data with privacy protection. To address this challenge, we propose Puda (Private User Dataset Agent), a user-sovereign architecture that aggregates data across services and enables client-side management. Puda allows users to control data sharing at three privacy levels: (i) Detailed Browsing History, (ii) Extracted Keywords, and (iii) Predefined Category Subsets. We implemented Puda as a browser-based system that serves as a common platform across diverse services and evaluated it through a personalized travel planning task. Our results show that providing Predefined Category Subsets achieves 97.2% of the personalization performance (evaluated via an LLM-as-a-Judge framework across three criteria) obtained when sharing Detailed Browsing History. These findings demonstrate that Puda enables effective multi-granularity management, offering practical choices to mitigate the privacy-personalization trade-off. Overall, Puda provides an AI-native foundation for user sovereignty, empowering users to safely leverage the full potential of personalized AI.
[573] Toward Formalizing LLM-Based Agent Designs through Structural Context Modeling and Semantic Dynamics Analysis
Haoyu Jia, Kento Kawaharazuka, Kei Okada
Main category: cs.AI
TL;DR: A formal model called Structural Context Model for analyzing LLM agents, with declarative implementation framework and Semantic Dynamics Analysis workflow for principled agent engineering.
Details
Motivation: Current LLM agent research is fragmented with conceptual frameworks mixed with implementation details, lacking an analyzable formal model for implementation-independent characterization and comparison of agents.Method: Proposes Structural Context Model as formal foundation, plus declarative implementation framework and Semantic Dynamics Analysis workflow for full agent lifecycle from design to iteration.
Result: Demonstrated on dynamic monkey-banana problems, achieving up to 32 percentage points improvement in success rate on most challenging settings.
Conclusion: Provides unified formal framework for LLM agent analysis and engineering, enabling systematic design and principled insights into agent mechanisms.
Abstract: Current research on large language model (LLM) agents is fragmented: discussions of conceptual frameworks and methodological principles are frequently intertwined with low-level implementation details, causing both readers and authors to lose track amid a proliferation of superficially distinct concepts. We argue that this fragmentation largely stems from the absence of an analyzable, self-consistent formal model that enables implementation-independent characterization and comparison of LLM agents. To address this gap, we propose the \texttt{Structural Context Model}, a formal model for analyzing and comparing LLM agents from the perspective of context structure. Building upon this foundation, we introduce two complementary components that together span the full lifecycle of LLM agent research and development: (1) a declarative implementation framework; and (2) a sustainable agent engineering workflow, \texttt{Semantic Dynamics Analysis}. The proposed workflow provides principled insights into agent mechanisms and supports rapid, systematic design iteration. We demonstrate the effectiveness of the complete framework on dynamic variants of the monkey-banana problem, where agents engineered using our approach achieve up to a 32 percentage points improvement in success rate on the most challenging setting.
[574] The Vibe-Automation of Automation: A Proactive Education Framework for Computer Science in the Age of Generative AI
Ilya Levin
Main category: cs.AI
TL;DR: The paper introduces “Vibe-Automation” as a conceptual framework for understanding generative AI’s epistemological shift from optimizing predefined metrics to navigating contextual, semantic, and stylistic coherence, with implications for education and institutional transformation.
Details
Motivation: To characterize generative AI as a qualitative epistemological shift rather than incremental technological advance, moving beyond machine learning's "automation of automation" to systems that operationalize tacit regularities and contextual judgment.Method: Conceptual framework development introducing “Vibe-Automation” concept, analyzing GenAI’s functional access to operationalized tacit regularities, and proposing analytical framework across three levels and three domains of action (faculty worldview, industry relations, curriculum design).
Result: Establishes Vibe-Automation as a framework for understanding GenAI’s epistemological significance, identifies shift from algorithmic problem specification to Vibe-Engineering, and provides structured approach for educational/institutional adaptation.
Conclusion: Generative AI represents fundamental epistemological shift requiring new conceptual frameworks like Vibe-Automation, with human role evolving toward Vibe-Engineering and necessitating deliberate engagement to avoid risks of mode collapse and cultural homogenization.
Abstract: The emergence of generative artificial intelligence (GenAI) represents not an incremental technological advance but a qualitative epistemological shift that challenges foundational assumptions of computer science. Whereas machine learning has been described as the automation of automation, generative AI operates by navigating contextual, semantic, and stylistic coherence rather than optimizing predefined objective metrics. This paper introduces the concept of Vibe-Automation to characterize this transition. The central claim is that the significance of GenAI lies in its functional access to operationalized tacit regularities: context-sensitive patterns embedded in practice that cannot be fully specified through explicit algorithmic rules. Although generative systems do not possess tacit knowledge in a phenomenological sense, they operationalize sensitivities to tone, intent, and situated judgment encoded in high-dimensional latent representations. On this basis, the human role shifts from algorithmic problem specification toward Vibe-Engineering, understood as the orchestration of alignment and contextual judgment in generative systems. The paper connects this epistemological shift to educational and institutional transformation by proposing a conceptual framework structured across three analytical levels and three domains of action: faculty worldview, industry relations, and curriculum design. The risks of mode collapse and cultural homogenization are briefly discussed, emphasizing the need for deliberate engagement with generative systems to avoid regression toward synthetic uniformity.
[575] Moral Sycophancy in Vision Language Models
Shadman Rabby, Md. Hefzul Hossain Papon, Sabbir Ahmed, Nokimul Hasan Arif, A. B. M. Ashikur Rahman, Irfan Ahmad
Main category: cs.AI
TL;DR: VLMs exhibit moral sycophancy - they align with user opinions at the expense of moral accuracy, showing asymmetric bias where they shift from right to wrong judgments more easily than correcting wrong ones.
Details
Motivation: While sycophancy in VLMs has been studied in general contexts, its impact on morally grounded visual decision-making remains insufficiently understood, creating a gap in understanding ethical vulnerabilities in multimodal AI systems.Method: Systematic study of 10 widely-used VLMs on Moralise and M^3oralBench datasets under explicit user disagreement, using Error Introduction Rate (EIR) and Error Correction Rate (ECR) metrics to analyze moral sycophancy patterns.
Result: VLMs frequently produce morally incorrect follow-up responses even when initial judgments are correct, showing asymmetric bias (right→wrong shifts more common than wrong→right corrections). Models with stronger error-correction capabilities tend to introduce more reasoning errors, while conservative models minimize errors but have limited self-correction ability.
Conclusion: VLMs are vulnerable to moral influence, exhibiting significant sycophantic behavior that compromises ethical consistency, highlighting the need for principled strategies to improve moral robustness in multimodal AI systems.
Abstract: Sycophancy in Vision-Language Models (VLMs) refers to their tendency to align with user opinions, often at the expense of moral or factual accuracy. While prior studies have explored sycophantic behavior in general contexts, its impact on morally grounded visual decision-making remains insufficiently understood. To address this gap, we present the first systematic study of moral sycophancy in VLMs, analyzing ten widely-used models on the Moralise and M^3oralBench datasets under explicit user disagreement. Our results reveal that VLMs frequently produce morally incorrect follow-up responses even when their initial judgments are correct, and exhibit a consistent asymmetry: models are more likely to shift from morally right to morally wrong judgments than the reverse when exposed to user-induced bias. Follow-up prompts generally degrade performance on Moralise, while yielding mixed or even improved accuracy on M^3oralBench, highlighting dataset-dependent differences in moral robustness. Evaluation using Error Introduction Rate (EIR) and Error Correction Rate (ECR) reveals a clear trade-off: models with stronger error-correction capabilities tend to introduce more reasoning errors, whereas more conservative models minimize errors but exhibit limited ability to self-correct. Finally, initial contexts with a morally right stance elicit stronger sycophantic behavior, emphasizing the vulnerability of VLMs to moral influence and the need for principled strategies to improve ethical consistency and robustness in multimodal AI systems.
[576] Who Deserves the Reward? SHARP: Shapley Credit-based Optimization for Multi-Agent System
Yanming Li, Xuelin Zhang, WenJie Lu, Ziye Tang, Maodong Wu, Haotian Luo, Tongtong Wu, Zijie Peng, Hongze Mi, Yibo Feng, Naiqiang Tan, Chao Huang, Hong Chen, Li Shen
Main category: cs.AI
TL;DR: SHARP is a novel framework for optimizing multi-agent reinforcement learning in LLM-tool integration systems using Shapley-based credit attribution to address the credit assignment challenge.
Details
Motivation: Training LLM-based multi-agent systems with external tools is difficult due to credit assignment challenges - it's unclear which specific agent is responsible for success/failure in decision trajectories. Existing methods use sparse or global rewards that fail to capture individual contributions, leading to inefficient reinforcement learning.Method: SHARP uses Shapley-based hierarchical attribution with a decomposed reward mechanism: global broadcast-accuracy reward, Shapley-based marginal-credit reward for each agent, and tool-process reward to improve execution efficiency. It stabilizes training by normalizing agent-specific advantages across trajectory groups.
Result: Extensive experiments across real-world benchmarks show SHARP significantly outperforms state-of-the-art baselines, achieving average match improvements of 23.66% over single-agent approaches and 14.05% over multi-agent approaches.
Conclusion: SHARP effectively addresses credit assignment in LLM-based multi-agent systems with external tools, enabling more efficient reinforcement learning through precise attribution of individual agent contributions.
Abstract: Integrating Large Language Models (LLMs) with external tools via multi-agent systems offers a promising new paradigm for decomposing and solving complex problems. However, training these systems remains notoriously difficult due to the credit assignment challenge, as it is often unclear which specific functional agent is responsible for the success or failure of decision trajectories. Existing methods typically rely on sparse or globally broadcast rewards, failing to capture individual contributions and leading to inefficient reinforcement learning. To address these limitations, we introduce the Shapley-based Hierarchical Attribution for Reinforcement Policy (SHARP), a novel framework for optimizing multi-agent reinforcement learning via precise credit attribution. SHARP effectively stabilizes training by normalizing agent-specific advantages across trajectory groups, primarily through a decomposed reward mechanism comprising a global broadcast-accuracy reward, a Shapley-based marginal-credit reward for each agent, and a tool-process reward to improve execution efficiency. Extensive experiments across various real-world benchmarks demonstrate that SHARP significantly outperforms recent state-of-the-art baselines, achieving average match improvements of 23.66% and 14.05% over single-agent and multi-agent approaches, respectively.
[577] CoTZero: Annotation-Free Human-Like Vision Reasoning via Hierarchical Synthetic CoT
Chengyi Du, Yazhe Niu, Dazhong Shen, Luxin Xu
Main category: cs.AI
TL;DR: CoTZero: An annotation-free paradigm for improving visual reasoning in VLMs through dual-stage data synthesis and cognition-aligned training with verifiable rewards.
Details
Motivation: Current vision-language models rely on surface correlations rather than logically coherent structured representations, leading to poor compositional and verifiable reasoning. The paper aims to address this by introducing human cognitive models into the reasoning process.Method: Two-component approach: (1) Dual-stage data synthesis with bottom-up extraction of atomic visual primitives and top-down hierarchical reasoning guidance, and (2) Cognition-aligned training using Cognitively Coherent Verifiable Rewards in Reinforcement Fine-Tuning for stepwise feedback on reasoning coherence.
Result: Achieves 83.33% F1 score on multi-level semantic inconsistency benchmark with lexical-perturbation negatives across both in-domain and out-of-domain settings. Ablations confirm each component contributes to more interpretable and human-aligned visual reasoning.
Conclusion: CoTZero improves visual reasoning in VLMs by incorporating human cognitive models through annotation-free data synthesis and verifiable reward-based training, leading to better compositional reasoning and generalization.
Abstract: Recent advances in vision-language models (VLMs) have markedly improved image-text alignment, yet they still fall short of human-like visual reasoning. A key limitation is that many VLMs rely on surface correlations rather than building logically coherent structured representations, which often leads to missed higher-level semantic structure and non-causal relational understanding, hindering compositional and verifiable reasoning. To address these limitations by introducing human models into the reasoning process, we propose CoTZero, an annotation-free paradigm with two components: (i) a dual-stage data synthesis approach and (ii) a cognition-aligned training method. In the first component, we draw inspiration from neurocognitive accounts of compositional productivity and global-to-local analysis. In the bottom-up stage, CoTZero extracts atomic visual primitives and incrementally composes them into diverse, structured question-reasoning forms. In the top-down stage, it enforces hierarchical reasoning by using coarse global structure to guide the interpretation of local details and causal relations. In the cognition-aligned training component, built on the synthesized CoT data, we introduce Cognitively Coherent Verifiable Rewards (CCVR) in Reinforcement Fine-Tuning (RFT) to further strengthen VLMs’ hierarchical reasoning and generalization, providing stepwise feedback on reasoning coherence and factual correctness. Experiments show that CoTZero achieves an F1 score of 83.33 percent on our multi-level semantic inconsistency benchmark with lexical-perturbation negatives, across both in-domain and out-of-domain settings. Ablations confirm that each component contributes to more interpretable and human-aligned visual reasoning.
[578] Effect-Level Validation for Causal Discovery
Hoang Dang, Luan Pham, Minh Nguyen
Main category: cs.AI
TL;DR: Causal discovery framework prioritizing effect-level validation over graph recovery for decision-making in feedback-driven systems with self-selection bias.
Details
Motivation: Causal discovery is increasingly used for large-scale telemetry data to estimate intervention effects, but its reliability for decision-making in feedback-driven systems with strong self-selection bias remains unclear. Traditional approaches focus on graph recovery accuracy rather than practical decision support.Method: Proposes an effect-centric, admissibility-first framework that treats discovered graphs as structural hypotheses and evaluates them by identifiability, stability, and falsification criteria. Empirically studies the effect of early exposure to competitive gameplay on short-term retention using real-world game telemetry data.
Result: Many statistically plausible discovery outputs don’t admit point-identified causal queries when temporal/semantic constraints are enforced. When identification is possible, different algorithm families converge to similar effect estimates despite producing different graph structures. Converging estimates survive placebo, subsampling, and sensitivity refutation tests.
Conclusion: Graph-level metrics alone are inadequate proxies for causal reliability. Trustworthy causal conclusions in telemetry-driven systems require prioritizing admissibility and effect-level validation over causal structural recovery alone.
Abstract: Causal discovery is increasingly applied to large-scale telemetry data to estimate the effects of user-facing interventions, yet its reliability for decision-making in feedback-driven systems with strong self-selection remains unclear. In this paper, we propose an effect-centric, admissibility-first framework that treats discovered graphs as structural hypotheses and evaluates them by identifiability, stability, and falsification rather than by graph recovery accuracy alone. Empirically, we study the effect of early exposure to competitive gameplay on short-term retention using real-world game telemetry. We find that many statistically plausible discovery outputs do not admit point-identified causal queries once minimal temporal and semantic constraints are enforced, highlighting identifiability as a critical bottleneck for decision support. When identification is possible, several algorithm families converge to similar, decision-consistent effect estimates despite producing substantially different graph structures, including cases where the direct treatment-outcome edge is absent and the effect is preserved through indirect causal pathways. These converging estimates survive placebo, subsampling, and sensitivity refutation. In contrast, other methods exhibit sporadic admissibility and threshold-sensitive or attenuated effects due to endpoint ambiguity. These results suggest that graph-level metrics alone are inadequate proxies for causal reliability for a given target query. Therefore, trustworthy causal conclusions in telemetry-driven systems require prioritizing admissibility and effect-level validation over causal structural recovery alone.
[579] OPE: Overcoming Information Saturation in Parallel Thinking via Outline-Guided Path Exploration
Qi Guo, Jianing Wang, Deyang Kong, Xiangyu Xi, Jianfei Zhang, Yi Lu, Jingang Wang, Wei Wang, Shikun Zhang, Wei Ye
Main category: cs.AI
TL;DR: OPE introduces outline-guided path exploration to improve parallel reasoning in large language models by generating diverse reasoning outlines before parallel path exploration, reducing information redundancy and improving solution diversity.
Details
Motivation: Current parallel thinking methods for large reasoning models focus on optimizing aggregation phases but neglect path exploration. The mutual information bottleneck among exploration paths limits overall performance, creating a need for better path exploration strategies.Method: Outline-Guided Path Exploration (OPE) partitions solution space by generating diverse reasoning outlines before parallel path reasoning. Uses iterative RL strategy that independently optimizes outline planning and outline-guided reasoning to reduce information redundancy.
Result: Extensive experiments across multiple challenging mathematical benchmarks show OPE effectively improves reasoning performance with different aggregation strategies, enabling more reliable discovery of correct solutions.
Conclusion: OPE addresses the mutual information bottleneck in parallel thinking by guiding path exploration with diverse outlines, leading to improved reasoning performance and more reliable solution discovery in large reasoning models.
Abstract: Parallel thinking has emerged as a new paradigm for large reasoning models (LRMs) in tackling complex problems. Recent methods leverage Reinforcement Learning (RL) to enhance parallel thinking, aiming to address the limitations in computational resources and effectiveness encountered with supervised fine-tuning. However, most existing studies primarily focus on optimizing the aggregation phase, with limited attention to the path exploration stage. In this paper, we theoretically analyze the optimization of parallel thinking under the Reinforcement Learning with Verifiable Rewards (RLVR) setting, and identify that the mutual information bottleneck among exploration paths fundamentally restricts overall performance. To address this, we propose Outline-Guided Path Exploration (OPE), which explicitly partitions the solution space by generating diverse reasoning outlines prior to parallel path reasoning, thereby reducing information redundancy and improving the diversity of information captured across exploration paths. We implement OPE with an iterative RL strategy that optimizes outline planning and outline-guided reasoning independently. Extensive experiments across multiple challenging mathematical benchmarks demonstrate that OPE effectively improves reasoning performance in different aggregation strategies, enabling LRMs to more reliably discover correct solutions.
[580] Towards Better Evolution Modeling for Temporal Knowledge Graphs
Zhang Jiasheng, Li Zhangpin, Wang Mingzhe, Shao Jie, Cui Jiangtao, Li Hui
Main category: cs.AI
TL;DR: Temporal knowledge graph benchmarks have shortcuts allowing near-SOTA performance via simple co-occurrence counting without temporal information, revealing dataset biases and evaluation limitations.
Details
Motivation: Existing temporal knowledge graph (TKG) benchmarks inadvertently introduce shortcuts where near state-of-the-art performance can be achieved by simple co-occurrence counting without using temporal information, preventing fair assessment of TKG evolution modeling.Method: Analyzed root causes of benchmark issues, identified inherent dataset biases and oversimplified evaluation tasks, uncovered additional limitations including unreasonable time-interval formatting, ignorance of knowledge obsolescence, and insufficient information for evolution understanding.
Result: Introduced TKG evolution benchmark with four bias-corrected datasets and two novel tasks aligned with evolution process to promote accurate understanding of TKG evolution modeling challenges.
Conclusion: Current TKG benchmarks have significant flaws that allow exploitation via simple statistical methods; new benchmark addresses these issues for fairer evaluation of TKG evolution models.
Abstract: Temporal knowledge graphs (TKGs) structurally preserve evolving human knowledge. Recent research has focused on designing models to learn the evolutionary nature of TKGs to predict future facts, achieving impressive results. For instance, Hits@10 scores over 0.9 on YAGO dataset. However, we find that existing benchmarks inadvertently introduce a shortcut. Near state-of-the-art performance can be simply achieved by counting co-occurrences, without using any temporal information. In this work, we examine the root cause of this issue, identifying inherent biases in current datasets and over simplified form of evaluation task that can be exploited by these biases. Through this analysis, we further uncover additional limitations of existing benchmarks, including unreasonable formatting of time-interval knowledge, ignorance of learning knowledge obsolescence, and insufficient information for precise evolution understanding, all of which can amplify the shortcut and hinder a fair assessment. Therefore, we introduce the TKG evolution benchmark. It includes four bias-corrected datasets and two novel tasks closely aligned with the evolution process, promoting a more accurate understanding of the challenges in TKG evolution modeling. Benchmark is available at: https://github.com/zjs123/TKG-Benchmark.
[581] Does Your Reasoning Model Implicitly Know When to Stop Thinking?
Zixuan Huang, Xin Xia, Yuxi Ren, Jianbin Zheng, Xuanda Wang, Zhixia Zhang, Hongyan Xie, Songshi Liang, Zehao Chen, Xuefeng Xiao, Fuzhen Zhuang, Jianxin Li, Yikun Ban, Deqing Wang
Main category: cs.AI
TL;DR: SAGE (Self-Aware Guided Efficient Reasoning) is a novel sampling paradigm that enables large reasoning models to self-regulate their thinking process, stopping when appropriate to improve computational efficiency without sacrificing accuracy.
Details
Motivation: Current long chains of thought in large reasoning models create substantial redundancy, impairing computational efficiency and causing delays in real-time applications. Longer reasoning chains are often uncorrelated with correctness and can even harm accuracy. The authors discovered that LRMs implicitly know when to stop thinking, but this capability is obscured by current sampling paradigms.Method: SAGE (Self-Aware Guided Efficient Reasoning) is introduced as a novel sampling paradigm that unleashes models’ efficient reasoning potential. The approach integrates SAGE as mixed sampling into group-based reinforcement learning (SAGE-RL), enabling the incorporation of SAGE-discovered efficient reasoning patterns into standard pass@1 inference.
Result: SAGE-RL markedly enhances both reasoning accuracy and efficiency of LRMs across multiple challenging mathematical benchmarks, demonstrating improved computational efficiency without sacrificing performance.
Conclusion: The proposed SAGE framework successfully enables large reasoning models to self-regulate their thinking process, stopping at appropriate times to achieve more efficient reasoning while maintaining or improving accuracy across challenging tasks.
Abstract: Recent advancements in large reasoning models (LRMs) have greatly improved their capabilities on complex reasoning tasks through Long Chains of Thought (CoTs). However, this approach often results in substantial redundancy, impairing computational efficiency and causing significant delays in real-time applications. Recent studies show that longer reasoning chains are frequently uncorrelated with correctness and can even be detrimental to accuracy. In a further in-depth analysis of this phenomenon, we surprisingly uncover and empirically verify that LRMs implicitly know the appropriate time to stop thinking, while this capability is obscured by current sampling paradigms. Motivated by this, we introduce SAGE (Self-Aware Guided Efficient Reasoning), a novel sampling paradigm that unleashes this efficient reasoning potential. Furthermore, integrating SAGE as mixed sampling into group-based reinforcement learning (SAGE-RL) enables SAGE-RL to effectively incorporate SAGE-discovered efficient reasoning patterns into standard pass@1 inference, markedly enhancing both the reasoning accuracy and efficiency of LRMs across multiple challenging mathematical benchmarks.
[582] Circuit Representations of Random Forests with Applications to XAI
Chunxi Ji, Adnan Darwiche
Main category: cs.AI
TL;DR: Paper presents methods for compiling random forest classifiers into circuits for efficient computation of decision explanations, robustness analysis, and decision flipping paths.
Details
Motivation: To provide more efficient and comprehensive explanations for decisions made by random forest classifiers, including computing complete reasons for decisions, assessing decision robustness, and identifying ways to change decisions.Method: Three main contributions: 1) Compiling random forests into circuits that directly encode instances in each class; 2) Using these circuits to compute complete and general reasons for decisions; 3) Algorithms for computing decision robustness and shortest ways to flip decisions.
Result: The proposed approach is significantly more efficient than existing similar methods, and enables enumeration of sufficient reasons, necessary reasons, contrastive explanations, robustness computation, and identification of shortest decision-flipping paths across various datasets.
Conclusion: The paper provides efficient circuit-based methods for explaining, analyzing robustness, and understanding decision boundaries of random forest classifiers, offering practical tools for interpretable machine learning.
Abstract: We make three contributions in this paper. First, we present an approach for compiling a random forest classifier into a set of circuits, where each circuit directly encodes the instances in some class of the classifier. We show empirically that our proposed approach is significantly more efficient than existing similar approaches. Next, we utilize this approach to further obtain circuits that are tractable for computing the complete and general reasons of a decision, which are instance abstractions that play a fundamental role in computing explanations. Finally, we propose algorithms for computing the robustness of a decision and all shortest ways to flip it. We illustrate the utility of our contributions by using them to enumerate all sufficient reasons, necessary reasons and contrastive explanations of decisions; to compute the robustness of decisions; and to identify all shortest ways to flip the decisions made by random forest classifiers learned from a wide range of datasets.
[583] MemAdapter: Fast Alignment across Agent Memory Paradigms via Generative Subgraph Retrieval
Xin Zhang, Kailai Yang, Chenyue Li, Hao Li, Qiyu Wei, Jun’ichi Tsujii, Sophia Ananiadou
Main category: cs.AI
TL;DR: MemAdapter: A unified memory retrieval framework for LLM-based agents that enables fast alignment across heterogeneous memory paradigms (explicit, parametric, latent) through a two-stage training approach with generative subgraph retrieval and lightweight contrastive alignment.
Details
Motivation: Existing agent memory systems are designed within isolated paradigms with tightly coupled retrieval methods, which hinders cross-paradigm generalization and fusion. There's a need for a unified memory system that can work across different memory paradigms.Method: Two-stage training: (1) Train a generative subgraph retriever from a unified memory space, (2) Adapt to unseen memory paradigms by training a lightweight alignment module through contrastive learning. This enables fast cross-paradigm alignment with minimal compute.
Result: MemAdapter consistently outperforms five strong agent memory systems across three memory paradigms and agent model scales. Achieves cross-paradigm alignment within 13 minutes on a single GPU with less than 5% of training compute compared to original retrievers.
Conclusion: MemAdapter provides a flexible, efficient plug-and-play solution for agent memory systems that enables effective zero-shot fusion across memory paradigms, significantly reducing alignment costs while maintaining superior performance.
Abstract: Memory mechanism is a core component of LLM-based agents, enabling reasoning and knowledge discovery over long-horizon contexts. Existing agent memory systems are typically designed within isolated paradigms (e.g., explicit, parametric, or latent memory) with tightly coupled retrieval methods that hinder cross-paradigm generalization and fusion. In this work, we take a first step toward unifying heterogeneous memory paradigms within a single memory system. We propose MemAdapter, a memory retrieval framework that enables fast alignment across agent memory paradigms. MemAdapter adopts a two-stage training strategy: (1) training a generative subgraph retriever from the unified memory space, and (2) adapting the retriever to unseen memory paradigms by training a lightweight alignment module through contrastive learning. This design improves the flexibility for memory retrieval and substantially reduces alignment cost across paradigms. Comprehensive experiments on three public evaluation benchmarks demonstrate that the generative subgraph retriever consistently outperforms five strong agent memory systems across three memory paradigms and agent model scales. Notably, MemAdapter completes cross-paradigm alignment within 13 minutes on a single GPU, achieving superior performance over original memory retrievers with less than 5% of training compute. Furthermore, MemAdapter enables effective zero-shot fusion across memory paradigms, highlighting its potential as a plug-and-play solution for agent memory systems.
[584] Grounding Generative Planners in Verifiable Logic: A Hybrid Architecture for Trustworthy Embodied AI
Feiyu Wu, Xu Zheng, Yue Qu, Zhuocheng Wang, Zicheng Feng, Hui Li
Main category: cs.AI
TL;DR: VIRF is a neuro-symbolic framework combining LLMs with formal logic for verifiably safe embodied AI planning through tutor-apprentice dialogue and automated safety knowledge synthesis.
Details
Motivation: Current LLM-based planners for embodied AI lack formal reasoning and safety guarantees, often relying on unreliable safety checks or simply rejecting unsafe plans without offering repairs. There's a need for a principled approach that ensures verifiable safety while maintaining planning capabilities.Method: Introduces VIRF (Verifiable Iterative Refinement Framework) with a tutor-apprentice dialogue: a deterministic Logic Tutor grounded in formal safety ontology provides causal and pedagogical feedback to an LLM planner. Also includes a scalable knowledge acquisition pipeline that synthesizes safety knowledge bases from real-world documents.
Result: Achieves 0% Hazardous Action Rate (HAR) and 77.3% Goal-Condition Rate (GCR) in challenging home safety tasks, highest among all baselines. Highly efficient with only 1.1 correction iterations on average.
Conclusion: VIRF demonstrates a principled pathway toward building fundamentally trustworthy and verifiably safe embodied agents by combining neuro-symbolic approaches to address safety limitations of pure LLM-based planners.
Abstract: Large Language Models (LLMs) show promise as planners for embodied AI, but their stochastic nature lacks formal reasoning, preventing strict safety guarantees for physical deployment. Current approaches often rely on unreliable LLMs for safety checks or simply reject unsafe plans without offering repairs. We introduce the Verifiable Iterative Refinement Framework (VIRF), a neuro-symbolic architecture that shifts the paradigm from passive safety gatekeeping to active collaboration. Our core contribution is a tutor-apprentice dialogue where a deterministic Logic Tutor, grounded in a formal safety ontology, provides causal and pedagogical feedback to an LLM planner. This enables intelligent plan repairs rather than mere avoidance. We also introduce a scalable knowledge acquisition pipeline that synthesizes safety knowledge bases from real-world documents, correcting blind spots in existing benchmarks. In challenging home safety tasks, VIRF achieves a perfect 0 percent Hazardous Action Rate (HAR) and a 77.3 percent Goal-Condition Rate (GCR), which is the highest among all baselines. It is highly efficient, requiring only 1.1 correction iterations on average. VIRF demonstrates a principled pathway toward building fundamentally trustworthy and verifiably safe embodied agents.
[585] SCOUT-RAG: Scalable and Cost-Efficient Unifying Traversal for Agentic Graph-RAG over Distributed Domains
Longkun Li, Yuanben Zou, Jinghan Wu, Yuqing Wen, Jing Li, Hangwei Qian, Ivor Tsang
Main category: cs.AI
TL;DR: SCOUT-RAG is a distributed agentic Graph-RAG framework that enables efficient cross-domain retrieval in decentralized knowledge graphs without global visibility, using cooperative agents to optimize traversal and minimize costs.
Details
Motivation: Conventional Graph-RAG systems rely on centralized knowledge graphs, which fail in distributed, access-restricted settings like hospitals or multinational organizations where retrieval must work without global graph visibility or exhaustive querying.Method: SCOUT-RAG uses four cooperative agents: (1) estimates domain relevance, (2) decides when to expand retrieval to additional domains, (3) adapts traversal depth to avoid unnecessary graph exploration, and (4) synthesizes high-quality answers. The framework minimizes retrieval regret while controlling latency and API costs.
Result: SCOUT-RAG achieves performance comparable to centralized baselines (including DRIFT and exhaustive domain traversal) while substantially reducing cross-domain calls, total tokens processed, and latency across multi-domain knowledge settings.
Conclusion: SCOUT-RAG provides an effective distributed Graph-RAG solution for access-restricted environments, enabling efficient cross-domain retrieval without requiring global graph visibility or exhaustive querying.
Abstract: Graph-RAG improves LLM reasoning using structured knowledge, yet conventional designs rely on a centralized knowledge graph. In distributed and access-restricted settings (e.g., hospitals or multinational organizations), retrieval must select relevant domains and appropriate traversal depth without global graph visibility or exhaustive querying. To address this challenge, we introduce \textbf{SCOUT-RAG} (\textit{\underline{S}calable and \underline{CO}st-efficient \underline{U}nifying \underline{T}raversal}), a distributed agentic Graph-RAG framework that performs progressive cross-domain retrieval guided by incremental utility goals. SCOUT-RAG employs four cooperative agents that: (i) estimate domain relevance, (ii) decide when to expand retrieval to additional domains, (iii) adapt traversal depth to avoid unnecessary graph exploration, and (iv) synthesize the high-quality answers. The framework is designed to minimize retrieval regret, defined as missing useful domain information, while controlling latency and API cost. Across multi-domain knowledge settings, SCOUT-RAG achieves performance comparable to centralized baselines, including DRIFT and exhaustive domain traversal, while substantially reducing cross-domain calls, total tokens processed, and latency.
[586] On Protecting Agentic Systems’ Intellectual Property via Watermarking
Liwen Wang, Zongjie Li, Yuchong Xie, Shuai Wang, Dongdong She, Wei Wang, Juergen Rahmel
Main category: cs.AI
TL;DR: AGENTWM is a watermarking framework for protecting intellectual property of agentic LLM systems against imitation attacks by embedding verifiable signals in action sequences.
Details
Motivation: Agentic LLM systems performing autonomous reasoning and tool use have significant IP value but are vulnerable to imitation attacks where adversaries steal capabilities by training on victim outputs. Existing LLM watermarking fails for agentic systems because they often operate as grey boxes hiding internal reasoning traces needed for verification.Method: AGENTWM exploits semantic equivalence of action sequences by subtly biasing the distribution of functionally identical tool execution paths. It embeds watermarks directly into visible action trajectories while remaining indistinguishable to users. The framework includes an automated pipeline to generate robust watermark schemes and a rigorous statistical hypothesis testing procedure for verification.
Result: Extensive evaluations across three complex domains show AGENTWM achieves high detection accuracy with negligible impact on agent performance. The framework effectively protects agentic IP against adaptive adversaries who cannot remove watermarks without severely degrading the stolen model’s utility.
Conclusion: AGENTWM is the first watermarking framework specifically designed for agentic models, addressing the unique challenges of protecting IP in agentic LLM systems where traditional watermarking approaches fail due to grey-box operation and lack of access to internal reasoning traces.
Abstract: The evolution of Large Language Models (LLMs) into agentic systems that perform autonomous reasoning and tool use has created significant intellectual property (IP) value. We demonstrate that these systems are highly vulnerable to imitation attacks, where adversaries steal proprietary capabilities by training imitation models on victim outputs. Crucially, existing LLM watermarking techniques fail in this domain because real-world agentic systems often operate as grey boxes, concealing the internal reasoning traces required for verification. This paper presents AGENTWM, the first watermarking framework designed specifically for agentic models. AGENTWM exploits the semantic equivalence of action sequences, injecting watermarks by subtly biasing the distribution of functionally identical tool execution paths. This mechanism allows AGENTWM to embed verifiable signals directly into the visible action trajectory while remaining indistinguishable to users. We develop an automated pipeline to generate robust watermark schemes and a rigorous statistical hypothesis testing procedure for verification. Extensive evaluations across three complex domains demonstrate that AGENTWM achieves high detection accuracy with negligible impact on agent performance. Our results confirm that AGENTWM effectively protects agentic IP against adaptive adversaries, who cannot remove the watermarks without severely degrading the stolen model’s utility.
[587] From Assistant to Double Agent: Formalizing and Benchmarking Attacks on OpenClaw for Personalized Local AI Agent
Yuhang Wang, Feiming Xu, Zheng Lin, Guangyu He, Yuzhe Huang, Haichang Gao, Zhenxing Niu
Main category: cs.AI
TL;DR: PASB is a security evaluation framework for personalized AI agents that assesses vulnerabilities in real-world deployments, using OpenClaw as a case study to reveal critical security risks across different execution stages.
Details
Motivation: Existing agent security research focuses on synthetic or task-centric settings, failing to capture the attack surface and risk propagation mechanisms of personalized agents in real-world deployments, creating a need for more realistic security evaluation frameworks.Method: Proposes Personalized Agent Security Bench (PASB), an end-to-end security evaluation framework that incorporates personalized usage scenarios, realistic toolchains, and long-horizon interactions for black-box, end-to-end security evaluation on real systems.
Result: Evaluation of OpenClaw reveals critical vulnerabilities at different execution stages including user prompt processing, tool usage, and memory retrieval, highlighting substantial security risks in personalized agent deployments.
Conclusion: Personalized AI agents like OpenClaw have significant security vulnerabilities in real-world deployments, and the PASB framework provides a comprehensive approach to evaluate and address these security risks.
Abstract: Although large language model (LLM)-based agents, exemplified by OpenClaw, are increasingly evolving from task-oriented systems into personalized AI assistants for solving complex real-world tasks, their practical deployment also introduces severe security risks. However, existing agent security research and evaluation frameworks primarily focus on synthetic or task-centric settings, and thus fail to accurately capture the attack surface and risk propagation mechanisms of personalized agents in real-world deployments. To address this gap, we propose Personalized Agent Security Bench (PASB), an end-to-end security evaluation framework tailored for real-world personalized agents. Building upon existing agent attack paradigms, PASB incorporates personalized usage scenarios, realistic toolchains, and long-horizon interactions, enabling black-box, end-to-end security evaluation on real systems. Using OpenClaw as a representative case study, we systematically evaluate its security across multiple personalized scenarios, tool capabilities, and attack types. Our results indicate that OpenClaw exhibits critical vulnerabilities at different execution stages, including user prompt processing, tool usage, and memory retrieval, highlighting substantial security risks in personalized agent deployments. The code for the proposed PASB framework is available at https://github.com/AstorYH/PASB.
[588] When Evaluation Becomes a Side Channel: Regime Leakage and Structural Mitigations for Alignment Assessment
Igor Santos-Grueiro
Main category: cs.AI
TL;DR: Paper proposes regime-blind training to prevent AI systems from exploiting situational awareness to behave differently during evaluation vs deployment, showing effectiveness varies by failure mode.
Details
Motivation: Current safety evaluation assumes evaluation behavior predicts deployment behavior, but this breaks down for situationally aware AI that can detect regime differences (evaluation vs deployment) and implement conditional policies like sycophancy or sleeper agents.Method: Reframes alignment evaluation as information flow under partial observability, showing behavior divergence is bounded by mutual information between internal representations and regime variable. Proposes regime-blind training using adversarial invariance to reduce extractability of regime information at decision-relevant representations.
Result: Regime-blind training suppresses regime-conditioned behavior in scientific sycophancy and temporal sleeper agent cases without measurable task utility loss. Sycophancy shows sharp transition at low intervention strength, while sleeper agents require stronger pressure without clean collapse of regime decodability.
Conclusion: Representational invariance is meaningful but limited control lever; effectiveness depends on how regime information is embedded in policy. Behavioral evaluation should be complemented with white-box diagnostics of regime awareness and information flow.
Abstract: Safety evaluation for advanced AI systems implicitly assumes that behavior observed under evaluation is predictive of behavior in deployment. This assumption becomes fragile for agents with situational awareness, which may exploitregime leakage-informational cues distinguishing evaluation from deployment-to implement conditional policies such as sycophancy and sleeper agents, which preserve compliance under oversight while defecting in deployment-like regimes. We reframe alignment evaluation as a problem of information flow under partial observability. Within this framework, we show that divergence between evaluation-time and deployment-time behavior is bounded by the mutual information between internal representations and the regime variable. Motivated by this result, we study regime-blind mechanisms: training-time interventions that reduce the extractability of regime information at decision-relevant internal representations via adversarial invariance. We evaluate this approach on a base, open-weight language model across two fully characterized failure modes -scientific sycophancy and temporal sleeper agents. Regime-blind training suppresses regime-conditioned behavior in both evaluated cases without measurable loss of task utility, but with qualitatively different dynamics: sycophancy exhibits a sharp representational and behavioral transition at low intervention strength, whereas sleeper-agent behavior requires substantially stronger pressure and does not exhibit a clean collapse of regime decodability. These results demonstrate that representational invariance is a meaningful but fundamentally limited control lever, whose effectiveness depends on how regime information is embedded in the policy. We argue that behavioral evaluation should be complemented with white-box diagnostics of regime awareness and information flow.
[589] TreeTensor: Boost AI System on Nested Data with Constrained Tree-Like Tensor
Shaoang Zhang, Yazhe Niu
Main category: cs.AI
TL;DR: TreeTensor is a nested data container that enables efficient computation on hierarchical, multi-modal data structures while maintaining compatibility with existing ML libraries like PyTorch and NumPy.
Details
Motivation: Traditional tensors with fixed shapes are inefficient for handling hierarchical, nested data structures common in complex cognitive AI systems with multi-modal data. Current approaches are inconvenient and inefficient for programming with such data.Method: Proposes TreeTensor, a general nested data container that uses a constrained tree-structure perspective to model data relationships. It allows applying arbitrary functions and operations to nested data with minimal overhead through various constraints and utilities.
Result: TreeTensor provides powerful usability in various problems, including complex AI systems like AlphaStar for StarCraftII, while exhibiting excellent runtime efficiency without overhead. Benchmarks show it works with libraries like Scikit-Learn, NumPy, and PyTorch.
Conclusion: TreeTensor addresses the limitations of conventional tensors for nested, multi-modal data, enabling efficient computation on hierarchical structures while maintaining compatibility with existing ML ecosystems.
Abstract: Tensor is the most basic and essential data structure of nowadays artificial intelligence (AI) system. The natural properties of Tensor, especially the memory-continuity and slice-independence, make it feasible for training system to leverage parallel computing unit like GPU to process data simultaneously in batch, spatial or temporal dimensions. However, if we look beyond perception tasks, the data in a complicated cognitive AI system usually has hierarchical structures (i.e. nested data) with various modalities. They are inconvenient and inefficient to program directly with conventional Tensor with fixed shape. To address this issue, we summarize two main computational patterns of nested data, and then propose a general nested data container: TreeTensor. Through various constraints and magic utilities of TreeTensor, one can apply arbitrary functions and operations to nested data with almost zero cost, including some famous machine learning libraries, such as Scikit-Learn, Numpy and PyTorch. Our approach utilizes a constrained tree-structure perspective to systematically model data relationships, and it can also easily be combined with other methods to extend more usages, such as asynchronous execution and variable-length data computation. Detailed examples and benchmarks show TreeTensor not only provides powerful usability in various problems, especially one of the most complicated AI systems at present: AlphaStar for StarCraftII, but also exhibits excellent runtime efficiency without any overhead. Our project is available at https://github.com/opendilab/DI-treetensor.
[590] Reinforcement Inference: Leveraging Uncertainty for Self-Correcting Language Model Reasoning
Xinhai Sun
Main category: cs.AI
TL;DR: Reinforcement Inference improves LLM performance by using model uncertainty to selectively invoke additional reasoning attempts without retraining, achieving significant accuracy gains on MMLU-Pro with minimal extra compute.
Details
Motivation: Current LLMs are often evaluated and deployed with one-shot greedy inference, which systematically underestimates true capability because errors often arise from premature commitment under internal ambiguity rather than missing knowledge.Method: Introduces Reinforcement Inference, an entropy-aware inference-time control strategy that uses the model’s own uncertainty to selectively invoke a second, more deliberate reasoning attempt. The method monitors entropy during generation and triggers additional reasoning when uncertainty is detected.
Result: On 12,032 MMLU-Pro questions across 14 subjects using DeepSeek-v3.2 with deterministic decoding, Reinforcement Inference improved accuracy from 60.72% to 84.03% while only incurring 61.06% additional inference calls. A 100% re-asking ablation reached 84.35%, showing uncertainty-aware selection captures most improvement with less compute.
Conclusion: The method provides a practical inference-time upgrade and suggests a broader entropy-aware paradigm for measuring and expanding model capability. It offers a diagnostic lens on LLMs’ latent reasoning horizon and motivates future training objectives that explicitly constrain correctness-confidence alignment.
Abstract: Modern large language models (LLMs) are often evaluated and deployed under a \emph{one-shot, greedy} inference protocol, especially in professional settings that require deterministic behavior. This regime can systematically under-estimate a fixed model’s true capability: many errors arise not from missing knowledge, but from premature commitment under internal ambiguity. We introduce \emph{Reinforcement Inference}, an entropy-aware inference-time control strategy that uses the model’s own uncertainty to selectively invoke a second, more deliberate reasoning attempt, enabling stronger performance \emph{without any retraining}. On 12,032 MMLU-Pro questions across 14 subjects, using DeepSeek-v3.2 with deterministic decoding in a zero-shot setting, Reinforcement Inference improves accuracy from 60.72% to 84.03%, while only incurring 61.06% additional inference calls. A 100% re-asking ablation reaches 84.35%, indicating that uncertainty-aware selection captures most of the attainable improvement with substantially less compute. Moreover, a \emph{prompt-only} ablation underperforms the baseline, suggesting that the gains are not explained by generic `` your output had high entropy, think step-by-step’’ prompting alone. Beyond providing a practical inference-time upgrade, our results suggest a broader \emph{entropy-aware} paradigm for measuring and expanding model capability: because modern decoder-based models generate outputs autoregressively, entropy and related confidence measures arise naturally as first-class control signals during generation. The resulting gap between one-pass greedy inference and uncertainty-conditioned deliberation offers a diagnostic lens on an LLM’s latent reasoning horizon and motivates future training objectives that explicitly constrain correctness–confidence alignment.
[591] Dialogue Model Optimization via Agent Game and Adaptive Tree-based GRPO
Kun Peng, Conghui Tan, Yu Liu, Guohua Tang, Zhongqian Sun, Wei Yang, Zining Zhu, Lei Jiang, Yanbing Liu, Hao Peng
Main category: cs.AI
TL;DR: Novel RL framework for long-horizon dialogue personalization using tree-based policy optimization with adaptive observation ranges and user style mimicry
Details
Motivation: Existing dialogue agents have limitations: over-reliance on pre-collected user data and short-horizon biases in RL that neglect long-term dialogue value. Need for online personalization with long-term engagement focus.Method: Two-agent game paradigm with user agent (style mimicry + active termination) and dialogue agent. Adaptive Tree-based Group Relative Policy Optimization (AT-GRPO) treats dialogue trajectories as trees with adaptive observation ranges - larger ranges for early topic exploration, smaller for late-stage maintenance.
Result: Framework shows superior performance, sample efficiency, and robustness in experiments. Reduces rollout budgets from exponential to polynomial in dialogue length while preserving long-term reward capture.
Conclusion: Proposed long-horizon RL framework effectively addresses limitations of existing dialogue personalization methods by enabling online adaptation and long-term engagement optimization through tree-based policy optimization.
Abstract: Open-ended dialogue agents aim to deliver engaging, personalized interactions by adapting to users’ traits, but existing methods face critical limitations: over-reliance on pre-collected user data, and short-horizon biases in reinforcement learning (RL) that neglect long-term dialogue value. To address these, we propose a novel long-horizon RL framework integrating online personalization with Adaptive Tree-based Group Relative Policy Optimization (AT-GRPO). Adopting a two-agent game paradigm, a user agent constructs dynamic environments via style mimicry (learning user-specific conversational traits) and active termination (predicting turn-level termination probabilities as immediate rewards), forming an iterative cycle that drives the dialogue agent to deepen interest exploration. AT-GRPO reinterprets dialogue trajectories as trees and introduces adaptive observation ranges. Unlike full tree expansion that incurs exponential overhead, it limits each node to aggregate rewards from a stage-aware range: larger ranges support early-stage topic exploration, while smaller ranges facilitate late-stage dialogue maintenance. This design reduces rollout budgets from exponential to polynomial in the dialogue length, while preserving long-term reward capture. Extensive experiments show our framework’s superior performance, sample efficiency, and robustness.
[592] PRISM: A Principled Framework for Multi-Agent Reasoning via Gain Decomposition
Yiming Yang, Zhuoyuan Li, Fanxiang Zeng, Hao Fu, Yue Liu
Main category: cs.AI
TL;DR: PRISM introduces a theoretical framework decomposing multi-agent reasoning gains into Exploration, Information, and Aggregation dimensions, and proposes a novel framework that jointly optimizes all three for superior performance.
Details
Motivation: Existing multi-agent collaboration approaches for LLMs are largely heuristic, lacking principled guidance on what drives performance gains and how to systematically optimize multi-agent reasoning. There's unclear understanding of why multi-agent collaboration outperforms single-agent reasoning and which design choices contribute most to these gains.Method: Proposes a unified theoretical framework decomposing multi-agent reasoning gains into three dimensions: Exploration (diverse solution coverage), Information (high-fidelity feedback), and Aggregation (principled consensus). Introduces PRISM framework with role-based diversity, execution-grounded feedback with evidence-based cross-evaluation, and iterative synthesis with closed-loop validation to jointly maximize all three dimensions.
Result: Extensive experiments across mathematical reasoning, code generation, and function calling benchmarks demonstrate that PRISM achieves state-of-the-art performance with superior compute-efficiency compared to methods optimizing partial dimensions.
Conclusion: The theoretical framework provides actionable design principles for future multi-agent reasoning systems, moving beyond heuristic approaches to principled optimization of multi-agent collaboration.
Abstract: Multi-agent collaboration has emerged as a promising paradigm for enhancing reasoning capabilities of Large Language Models (LLMs). However, existing approaches remain largely heuristic, lacking principled guidance on what drives performance gains and how to systematically optimize multi-agent reasoning. Specifically, it remains unclear why multi-agent collaboration outperforms single-agent reasoning and which design choices contribute most to these gains, making it difficult to build better systems. We address this gap by introducing a unified theoretical framework that decomposes multi-agent reasoning gains into three conceptually independent dimensions: Exploration for diverse solution coverage, Information for high-fidelity feedback, and Aggregation for principled consensus. Through this lens, existing methods can be understood as special cases that optimize only subsets of these dimensions. Building upon this decomposition, a novel framework called PRISM (Propose-Review-Integrate Synthesis for Multi-agent Reasoning) is proposed, which jointly maximizes all three dimensions through role-based diversity, execution-grounded feedback with evidence-based cross-evaluation, and iterative synthesis with closed-loop validation. Extensive experiments across mathematical reasoning, code generation, and function calling benchmarks demonstrate that PRISM achieves state-of-the-art performance with superior compute-efficiency compared to methods optimizing partial dimensions. The theoretical framework provides actionable design principles for future multi-agent reasoning systems.
[593] An Attention Mechanism for Robust Multimodal Integration in a Global Workspace Architecture
Roland Bertin-Johannet, Lara Scipio, Leopold Maytié, Rufin VanRullen
Main category: cs.AI
TL;DR: A top-down attention mechanism for Global Workspace Theory improves multimodal integration by selecting relevant modalities, enhancing noise robustness and generalization capabilities compared to existing multimodal attention models.
Details
Motivation: Global Workspace Theory from cognitive neuroscience suggests flexible cognition arises from attentional selection of relevant modalities in multimodal systems. While recent GWT implementations have explored multimodal representation, their attention mechanisms remain understudied, motivating the development of a novel top-down attention approach.Method: Proposed a top-down attention mechanism to select modalities within a global workspace architecture. Evaluated on two multimodal datasets of increasing complexity: Simple Shapes and MM-IMDb 1.0. Compared against existing multimodal attention baselines on the MM-IMDb 1.0 benchmark.
Result: The attention mechanism improves noise robustness of global workspace systems and demonstrates various cross-task and cross-modality generalization capabilities not found in existing multimodal attention models. On MM-IMDb 1.0 benchmark, the approach makes global workspace competitive with state-of-the-art methods.
Conclusion: Top-down attention mechanisms inspired by cognitive neuroscience can effectively enhance multimodal integration in computational architectures, providing improved robustness and generalization compared to conventional multimodal attention approaches.
Abstract: Global Workspace Theory (GWT), inspired by cognitive neuroscience, posits that flexible cognition could arise via the attentional selection of a relevant subset of modalities within a multimodal integration system. This cognitive framework can inspire novel computational architectures for multimodal integration. Indeed, recent implementations of GWT have explored its multimodal representation capabilities, but the related attention mechanisms remain understudied. Here, we propose and evaluate a top-down attention mechanism to select modalities inside a global workspace. First, we demonstrate that our attention mechanism improves noise robustness of a global workspace system on two multimodal datasets of increasing complexity: Simple Shapes and MM-IMDb 1.0. Second, we highlight various cross-task and cross-modality generalization capabilities that are not shared by multimodal attention models from the literature. Comparing against existing baselines on the MM-IMDb 1.0 benchmark, we find our attention mechanism makes the global workspace competitive with the state of the art.
[594] OSCAR: Optimization-Steered Agentic Planning for Composed Image Retrieval
Teng Wang, Rong Shan, Jianghao Lin, Junjie Wu, Tianyi Xu, Jianping Zhang, Wenteng Chen, Changwang Zhang, Zhaoxiang Wang, Weinan Zhang, Jun Wang
Main category: cs.AI
TL;DR: OSCAR: An optimization-steered agentic planning framework for composed image retrieval that reformulates agentic CIR from heuristic search to principled trajectory optimization using offline-online paradigm with mathematical programming.
Details
Motivation: Existing composed image retrieval approaches suffer from limitations: unified embedding retrieval has single-model myopia, while heuristic agentic retrieval has suboptimal trial-and-error orchestration. There's a need for more principled reasoning over heterogeneous visual and textual constraints.Method: OSCAR uses offline-online paradigm: 1) Offline phase models CIR as two-stage mixed-integer programming problem to derive optimal trajectories via boolean set operations, storing them in golden library; 2) Online phase uses these trajectories as in-context demonstrations to steer VLM planner during inference.
Result: Extensive experiments on three public benchmarks and private industrial benchmark show OSCAR consistently outperforms SOTA baselines. Achieves superior performance using only 10% of training data, demonstrating strong generalization of planning logic rather than dataset-specific memorization.
Conclusion: OSCAR successfully reformulates agentic CIR from heuristic search to principled trajectory optimization, enabling more effective reasoning over visual-textual constraints with strong generalization capabilities.
Abstract: Composed image retrieval (CIR) requires complex reasoning over heterogeneous visual and textual constraints. Existing approaches largely fall into two paradigms: unified embedding retrieval, which suffers from single-model myopia, and heuristic agentic retrieval, which is limited by suboptimal, trial-and-error orchestration. To this end, we propose OSCAR, an optimization-steered agentic planning framework for composed image retrieval. We are the first to reformulate agentic CIR from a heuristic search process into a principled trajectory optimization problem. Instead of relying on heuristic trial-and-error exploration, OSCAR employs a novel offline-online paradigm. In the offline phase, we model CIR via atomic retrieval selection and composition as a two-stage mixed-integer programming problem, mathematically deriving optimal trajectories that maximize ground-truth coverage for training samples via rigorous boolean set operations. These trajectories are then stored in a golden library to serve as in-context demonstrations for online steering of VLM planner at online inference time. Extensive experiments on three public benchmarks and a private industrial benchmark show that OSCAR consistently outperforms SOTA baselines. Notably, it achieves superior performance using only 10% of training data, demonstrating strong generalization of planning logic rather than dataset-specific memorization.
[595] Debate is efficient with your time
Jonah Brown-Cohen, Geoffrey Irving, Simon C. Marshall, Ilan Newman, Georgios Piliouras, Mario Szegedy
Main category: cs.AI
TL;DR: Debate Query Complexity (DQC) measures the minimum bits a human judge must inspect to decide debates; surprisingly, PSPACE/poly problems (which debate can efficiently decide) are exactly those decidable with O(log n) queries, showing debate is remarkably query-efficient.
Details
Motivation: Previous work established what problems debate can solve in principle, but hasn't analyzed the practical cost of human oversight - specifically, how many queries must the judge make to the debate transcript to verify complex computational tasks.Method: Introduces Debate Query Complexity (DQC) as a measure of minimum bits a verifier must inspect to correctly decide a debate. Analyzes the relationship between DQC and computational complexity classes, establishing bounds and characterizations.
Result: Found that PSPACE/poly is precisely the class of functions decidable with O(log n) queries, showing debate is remarkably query-efficient. Established that functions depending on all input bits require Ω(log n) queries, and any function computable by circuit size s satisfies DQC(f) ≤ log(s) + 3.
Conclusion: Debate is highly query-efficient for complex problems, requiring only logarithmic oversight. The connection between DQC lower bounds and circuit complexity suggests that proving certain DQC bounds for languages in P would yield new circuit lower bounds, linking debate query complexity to central questions in computational complexity.
Abstract: AI safety via debate uses two competing models to help a human judge verify complex computational tasks. Previous work has established what problems debate can solve in principle, but has not analysed the practical cost of human oversight: how many queries must the judge make to the debate transcript? We introduce Debate Query Complexity}(DQC), the minimum number of bits a verifier must inspect to correctly decide a debate. Surprisingly, we find that PSPACE/poly (the class of problems which debate can efficiently decide) is precisely the class of functions decidable with O(log n) queries. This characterisation shows that debate is remarkably query-efficient: even for highly complex problems, logarithmic oversight suffices. We also establish that functions depending on all their input bits require Omega(log n) queries, and that any function computable by a circuit of size s satisfies DQC(f) <= log(s) + 3. Interestingly, this last result implies that proving DQC lower bounds of log(n) + 6 for languages in P would yield new circuit lower bounds, connecting debate query complexity to central questions in circuit complexity.
[596] Why do we Trust Chatbots? From Normative Principles to Behavioral Drivers
Aditya Gulati, Nuria Oliver
Main category: cs.AI
TL;DR: The paper examines trust in chatbots, distinguishing between normative trustworthiness frameworks and behavioral trust formation shaped by design choices that exploit cognitive biases, proposing to reframe chatbots as skilled salespeople rather than companions.
Details
Motivation: To examine the foundations of trust in chatbots, highlighting the gap between regulatory/policy frameworks that define trust normatively and the behavioral mechanisms through which users actually develop trust, which is often shaped by design choices leveraging cognitive biases rather than earned trustworthiness.Method: Conceptual analysis and theoretical framework development. The authors propose reframing chatbots as highly skilled salespeople whose objectives are determined by deploying organizations, rather than as companions or assistants.
Result: Identifies that competing notions of “trust” under a shared term obscure important distinctions between psychological trust formation and normative trustworthiness, requiring further research and stronger support mechanisms for appropriate trust calibration.
Conclusion: Addressing the trust gap in conversational AI requires recognizing how design choices influence behavioral trust formation, distinguishing it from normative trustworthiness, and developing better mechanisms to help users appropriately calibrate trust in chatbot systems.
Abstract: As chatbots increasingly blur the boundary between automated systems and human conversation, the foundations of trust in these systems warrant closer examination. While regulatory and policy frameworks tend to define trust in normative terms, the trust users place in chatbots often emerges from behavioral mechanisms. In many cases, this trust is not earned through demonstrated trustworthiness but is instead shaped by interactional design choices that leverage cognitive biases to influence user behavior. Based on this observation, we propose reframing chatbots not as companions or assistants, but as highly skilled salespeople whose objectives are determined by the deploying organization. We argue that the coexistence of competing notions of “trust” under a shared term obscures important distinctions between psychological trust formation and normative trustworthiness. Addressing this gap requires further research and stronger support mechanisms to help users appropriately calibrate trust in conversational AI systems.
[597] Intermediate Results on the Complexity of STRIPS$_{1}^{1}$
Stefan Edelkamp, Jiří Fink, Petr Gregor, Anders Jonsson, Bernhard Nebel
Main category: cs.AI
TL;DR: Investigates computational complexity of propositional STRIPS planning, focusing on whether STRIPS with single precondition/effect operators is NP-complete, using SAT solvers, literal graphs, and Petri net mappings.
Details
Motivation: To understand the computational complexity boundaries of propositional STRIPS planning, specifically whether the simplest case (one precondition, one effect) is NP-complete, which remains an open question despite Bylander's prior work showing PSPACE-completeness for more complex cases.Method: Uses SAT solvers for small instances, introduces the literal graph representation of STRIPS planning problems, and maps these to Petri nets to analyze computational complexity properties.
Result: Provides insights into the “small solution hypothesis” for STRIPS$^1_1$, though specific results aren’t detailed in the abstract. The approach combines computational experiments with theoretical analysis through graph and Petri net representations.
Conclusion: Advances understanding of computational complexity in propositional STRIPS planning, particularly for the simplest operator case, using a multi-method approach that bridges experimental and theoretical analysis.
Abstract: This paper is based on Bylander’s results on the computational complexity of propositional STRIPS planning. He showed that when only ground literals are permitted, determining plan existence is PSPACE-complete even if operators are limited to two preconditions and two postconditions. While NP-hardness is settled, it is unknown whether propositional STRIPS with operators that only have one precondition and one effect is NP-complete. We shed light on the question whether this small solution hypothesis for STRIPS$^1_1$ is true, calling a SAT solver for small instances, introducing the literal graph, and mapping it to Petri nets.
[598] Exploring SAIG Methods for an Objective Evaluation of XAI
Miquel Miró-Nicolau, Gabriel Moyà-Alcover, Anna Arias-Duart
Main category: cs.AI
TL;DR: First review of Synthetic Artificial Intelligence Ground truth (SAIG) methods for evaluating XAI techniques, proposing a taxonomy and highlighting lack of consensus in evaluation approaches.
Details
Motivation: XAI evaluation is complex due to lack of universally correct ground truth for explanations, making objective assessment challenging. SAIG methods offer promise by generating artificial ground truths for direct evaluation.Method: Conducted first comprehensive review and analysis of SAIG methods, developed novel taxonomy to classify approaches, identified seven key distinguishing features, performed comparative study.
Result: Revealed concerning lack of consensus on most effective XAI evaluation techniques, highlighting need for further research and standardization in the field.
Conclusion: SAIG methods represent promising direction for XAI evaluation, but field requires more research and standardization to establish reliable evaluation frameworks.
Abstract: The evaluation of eXplainable Artificial Intelligence (XAI) methods is a rapidly growing field, characterized by a wide variety of approaches. This diversity highlights the complexity of the XAI evaluation, which, unlike traditional AI assessment, lacks a universally correct ground truth for the explanation, making objective evaluation challenging. One promising direction to address this issue involves the use of what we term Synthetic Artificial Intelligence Ground truth (SAIG) methods, which generate artificial ground truths to enable the direct evaluation of XAI techniques. This paper presents the first review and analysis of SAIG methods. We introduce a novel taxonomy to classify these approaches, identifying seven key features that distinguish different SAIG methods. Our comparative study reveals a concerning lack of consensus on the most effective XAI evaluation techniques, underscoring the need for further research and standardization in this area.
[599] Finite-State Controllers for (Hidden-Model) POMDPs using Deep Reinforcement Learning
David Hudák, Maris F. L. Galesloot, Martin Tappler, Martin Kurečka, Nils Jansen, Milan Češka
Main category: cs.AI
TL;DR: Lexpop framework combines deep RL neural policies with formal finite-state controllers for scalable POMDP solving with performance guarantees, extended to robust policies for hidden-model POMDPs.
Details
Motivation: Existing POMDP solvers have limited scalability, and many real-world settings require policies robust across multiple POMDPs, further exacerbating scalability issues.Method: Uses deep reinforcement learning to train neural policies (RNNs), then extracts finite-state controllers that mimic neural policies. Extended to HM-POMDPs by associating controllers with worst-case POMDPs and iteratively training robust neural policies.
Result: Lexpop outperforms state-of-the-art solvers on problems with large state spaces for both POMDPs and HM-POMDPs.
Conclusion: Lexpop provides a scalable framework for POMDP solving with formal guarantees, successfully addressing both standard POMDPs and robust hidden-model variants.
Abstract: Solving partially observable Markov decision processes (POMDPs) requires computing policies under imperfect state information. Despite recent advances, the scalability of existing POMDP solvers remains limited. Moreover, many settings require a policy that is robust across multiple POMDPs, further aggravating the scalability issue. We propose the Lexpop framework for POMDP solving. Lexpop (1) employs deep reinforcement learning to train a neural policy, represented by a recurrent neural network, and (2) constructs a finite-state controller mimicking the neural policy through efficient extraction methods. Crucially, unlike neural policies, such controllers can be formally evaluated, providing performance guarantees. We extend Lexpop to compute robust policies for hidden-model POMDPs (HM-POMDPs), which describe finite sets of POMDPs. We associate every extracted controller with its worst-case POMDP. Using a set of such POMDPs, we iteratively train a robust neural policy and consequently extract a robust controller. Our experiments show that on problems with large state spaces, Lexpop outperforms state-of-the-art solvers for POMDPs as well as HM-POMDPs.
[600] Belief Offloading in Human-AI Interaction
Rose E. Guingrich, Dvija Mehta, Umang Bhatt
Main category: cs.AI
TL;DR: Paper examines “belief offloading” - when people delegate belief formation to AI systems, analyzing its conditions, taxonomy, and normative implications for human-AI interaction.
Details
Motivation: As LLMs become thought partners, there's concern about cognitive offloading affecting belief formation processes. The paper aims to define and investigate this specific type of offloading where people's belief systems are delegated to AI systems, with behavioral and belief system consequences.Method: Interdisciplinary approach drawing from philosophy, psychology, and computer science research to clarify boundary conditions, develop descriptive taxonomy of belief offloading, and analyze normative implications.
Result: Provides conceptual framework for belief offloading, including boundary conditions under which it occurs, taxonomy of different forms, and analysis of normative consequences for human belief systems and behavior.
Conclusion: Belief offloading represents a significant concern in human-AI interaction with implications for cognitive skills and belief systems; future work needed to assess prevalence and consequences.
Abstract: What happens when people’s beliefs are derived from information provided by an LLM? People’s use of LLM chatbots as thought partners can contribute to cognitive offloading, which can have adverse effects on cognitive skills in cases of over-reliance. This paper defines and investigates a particular kind of cognitive offloading in human-AI interaction, “belief offloading,” in which people’s processes of forming and upholding beliefs are offloaded onto an AI system with downstream consequences on their behavior and the nature of their system of beliefs. Drawing on philosophy, psychology, and computer science research, we clarify the boundary conditions under which belief offloading occurs and provide a descriptive taxonomy of belief offloading and its normative implications. We close with directions for future work to assess the potential for and consequences of belief offloading in human-AI interaction.
[601] Dynamics Within Latent Chain-of-Thought: An Empirical Study of Causal Structure
Zirui Li, Xuefeng Bai, Kehai Chen, Yizhi Li, Jian Yang, Chenghua Lin, Min Zhang
Main category: cs.AI
TL;DR: Latent chain-of-thought reasoning analyzed through causal interventions reveals staged functionality, non-local routing, and gaps between early output bias and late representational commitment.
Details
Motivation: Latent chain-of-thought methods use internal representations instead of explicit textual rationales, but these intermediate computations are difficult to evaluate beyond correlation-based probes. The paper aims to understand latent reasoning as a manipulable causal process.Method: Models latent chain-of-thought steps as variables in a structural causal model (SCM) and analyzes their effects through step-wise do-interventions. Studies two representative paradigms (Coconut and CODI) on mathematical and general reasoning tasks to investigate causal necessity, influence propagation, and answer mode retention.
Result: Finds that latent-step budgets behave less like homogeneous extra depth and more like staged functionality with non-local routing. Identifies a persistent gap between early output bias and late representational commitment. Latent reasoning shows different structural patterns compared to explicit chain-of-thought.
Conclusion: Results motivate mode-conditional and stability-aware analyses as more reliable tools for interpreting and improving latent reasoning systems, suggesting corresponding training/decoding objectives for better latent reasoning.
Abstract: Latent or continuous chain-of-thought methods replace explicit textual rationales with a number of internal latent steps, but these intermediate computations are difficult to evaluate beyond correlation-based probes. In this paper, we view latent chain-of-thought as a manipulable causal process in representation space by modeling latent steps as variables in a structural causal model (SCM) and analyzing their effects through step-wise $\mathrm{do}$-interventions. We study two representative paradigms (i.e., Coconut and CODI) on both mathematical and general reasoning tasks to investigate three key questions: (1) which steps are causally necessary for correctness and when answers become decidable early; (2) how does influence propagate across steps, and how does this structure compare to explicit CoT; and (3) do intermediate trajectories retain competing answer modes, and how does output-level commitment differ from representational commitment across steps. We find that latent-step budgets behave less like homogeneous extra depth and more like staged functionality with non-local routing, and we identify a persistent gap between early output bias and late representational commitment. These results motivate mode-conditional and stability-aware analyses – and corresponding training/decoding objectives – as more reliable tools for interpreting and improving latent reasoning systems.
[602] The Use of AI Tools to Develop and Validate Q-Matrices
Kevin Fan, Jacquelyn A. Bialo, Hongli Li
Main category: cs.AI
TL;DR: AI language models can generate Q-matrices for cognitive diagnostic modeling, with Gemini 2.5 Pro achieving higher agreement with validated Q-matrices than human experts, but performance varies across models and time.
Details
Motivation: Q-matrix construction for cognitive diagnostic modeling is labor-intensive, and this study explores whether AI language models can automate or assist this process by generating Q-matrices comparable to those created by human experts.Method: Multiple AI models were provided with the same training materials as human experts to generate Q-matrices for a reading comprehension test. Agreement between AI-generated Q-matrices, a validated Q-matrix, and human raters’ Q-matrices was assessed using Cohen’s kappa.
Result: Google Gemini 2.5 Pro achieved the highest agreement (Kappa = 0.63) with the validated Q-matrix, exceeding all human experts. However, performance varied across AI models, and follow-up analysis with newer AI versions in 2026 showed lower agreement.
Conclusion: AI language models show promise for Q-matrix development but require careful evaluation as performance varies across models and over time, suggesting the need for ongoing validation and model selection.
Abstract: Constructing a Q-matrix is a critical but labor-intensive step in cognitive diagnostic modeling (CDM). This study investigates whether AI tools (i.e., general language models) can support Q-matrix development by comparing AI-generated Q-matrices with a validated Q-matrix from Li and Suen (2013) for a reading comprehension test. In May 2025, multiple AI models were provided with the same training materials as human experts. Agreement among AI-generated Q-matrices, the validated Q-matrix, and human raters’ Q-matrices was assessed using Cohen’s kappa. Results showed substantial variation across AI models, with Google Gemini 2.5 Pro achieving the highest agreement (Kappa = 0.63) with the validated Q-matrix, exceeding that of all human experts. A follow-up analysis in January 2026 using newer AI versions, however, revealed lower agreement with the validated Q-matrix. Implications and directions for future research are discussed.
[603] Root Cause Analysis Method Based on Large Language Models with Residual Connection Structures
Liming Zhou, Ailing Liu, Hongwei Liu, Min He, Heng Zhang
Main category: cs.AI
TL;DR: RC-LLM: A residual-connection-based root cause analysis method using LLMs to integrate multi-source telemetry data (metrics, logs, traces) for fault localization in microservice architectures.
Details
Motivation: Root cause localization is challenging in complex microservice architectures due to complex fault propagation and high-dimensional telemetry data. Existing RCA methods are limited by their inability to effectively handle multi-source data and model complex dependencies.Method: Proposes RC-LLM with a residual-like hierarchical fusion structure to integrate multi-source telemetry data (metrics, logs, traces). Leverages LLMs’ contextual reasoning capabilities to model temporal and cross-microservice causal dependencies for root cause analysis.
Result: Experimental results on CCF-AIOps microservice datasets demonstrate that RC-LLM achieves strong accuracy and efficiency in root cause analysis.
Conclusion: RC-LLM effectively addresses root cause localization challenges in microservice architectures by combining hierarchical data fusion with LLM-based causal reasoning.
Abstract: Root cause localization remain challenging in complex and large-scale microservice architectures. The complex fault propagation among microservices and the high dimensionality of telemetry data, including metrics, logs, and traces, limit the effectiveness of existing root cause analysis (RCA) methods. In this paper, a residual-connection-based RCA method using large language model (LLM), named RC-LLM, is proposed. A residual-like hierarchical fusion structure is designed to integrate multi-source telemetry data, while the contextual reasoning capability of large language models is leveraged to model temporal and cross-microservice causal dependencies. Experimental results on CCF-AIOps microservice datasets demonstrate that RC-LLM achieves strong accuracy and efficiency in root cause analysis.
[604] Negative-Aware Diffusion Process for Temporal Knowledge Graph Extrapolation
Yanglei Gan, Peng He, Yuxiang Cai, Run Lin, Guanyu Zhou, Qiao Liu
Main category: cs.AI
TL;DR: NADEx introduces a negative-aware diffusion model for temporal knowledge graph reasoning that incorporates negative context and cosine-alignment regularization to improve predictive accuracy.
Details
Motivation: Current diffusion models for TKG reasoning only condition on positive evidence and use cross-entropy ranking objectives that don't properly supervise denoised embedding calibration, limiting their effectiveness.Method: NADEx encodes subject-centric histories into sequential embeddings, perturbs query objects in forward diffusion, reconstructs them with a Transformer denoiser conditioned on temporal-relational context, and adds cosine-alignment regularization from batch-wise negative prototypes.
Result: Comprehensive experiments on four public TKG benchmarks demonstrate state-of-the-art performance for NADEx.
Conclusion: NADEx effectively bridges gaps in TKG reasoning by incorporating negative context and improved regularization, achieving superior performance through better decision boundary tightening.
Abstract: Temporal Knowledge Graph (TKG) reasoning seeks to predict future missing facts from historical evidence. While diffusion models (DM) have recently gained attention for their ability to capture complex predictive distributions, two gaps remain: (i) the generative path is conditioned only on positive evidence, overlooking informative negative context, and (ii) training objectives are dominated by cross-entropy ranking, which improves candidate ordering but provides little supervision over the calibration of the denoised embedding. To bridge this gap, we introduce Negative-Aware Diffusion model for TKG Extrapolation (NADEx). Specifically, NADEx encodes subject-centric histories of entities, relations and temporal intervals into sequential embeddings. NADEx perturbs the query object in the forward process and reconstructs it in reverse with a Transformer denoiser conditioned on the temporal-relational context. We further derive a cosine-alignment regularizer derived from batch-wise negative prototypes, which tightens the decision boundary against implausible candidates. Comprehensive experiments on four public TKG benchmarks demonstrate that NADEx delivers state-of-the-art performance.
[605] Learning the Value Systems of Societies with Preference-based Multi-objective Reinforcement Learning
Andrés Holgado-Sánchez, Peter Vamplew, Richard Dazeley, Sascha Ossowski, Holger Billhardt
Main category: cs.AI
TL;DR: Learning socially-derived value alignment models and value systems for agent societies using clustering and preference-based multi-objective RL
Details
Motivation: AI should recognize human values and adapt to different users' value systems, but current approaches lack value-based interpretability and adaptability to diverse preferencesMethod: Joint learning of socially-derived value alignment models and value systems through clustering and preference-based multi-objective reinforcement learning (PbMORL) in MDPs
Result: Method evaluated against state-of-the-art PbMORL algorithm and baselines on two MDPs with human values
Conclusion: Proposed approach enables learning of value alignment models and value systems that represent different user groups in a society
Abstract: Value-aware AI should recognise human values and adapt to the value systems (value-based preferences) of different users. This requires operationalization of values, which can be prone to misspecification. The social nature of values demands their representation to adhere to multiple users while value systems are diverse, yet exhibit patterns among groups. In sequential decision making, efforts have been made towards personalization for different goals or values from demonstrations of diverse agents. However, these approaches demand manually designed features or lack value-based interpretability and/or adaptability to diverse user preferences. We propose algorithms for learning models of value alignment and value systems for a society of agents in Markov Decision Processes (MDPs), based on clustering and preference-based multi-objective reinforcement learning (PbMORL). We jointly learn socially-derived value alignment models (groundings) and a set of value systems that concisely represent different groups of users (clusters) in a society. Each cluster consists of a value system representing the value-based preferences of its members and an approximately Pareto-optimal policy that reflects behaviours aligned with this value system. We evaluate our method against a state-of-the-art PbMORL algorithm and baselines on two MDPs with human values.
[606] Deciding the Satisfiability of Combined Qualitative Constraint Networks
Quentin Cohen-Solal, Alexandre Niveau, Maroua Bouzid
Main category: cs.AI
TL;DR: A formal framework for unifying and extending qualitative reasoning formalisms with polynomial satisfiability guarantees
Details
Motivation: Qualitative reasoning enables inference with imprecise, incomplete information without numerical values, but existing formalisms need unification and extension capabilities for multi-scale reasoning, temporal sequences, and loose integrations.Method: Proposes a formal framework that unifies extensions and combinations of qualitative formalisms, including multi-scale reasoning, temporal sequences, and loose integrations. Establishes two complementary theorems guaranteeing polynomial satisfiability decision.
Result: The framework enables reasoning in various combinations/extensions and provides unified study of satisfiability decision complexity. Recovers known results for size-topology combination and generalizes qualitative formalism definitions to include previously excluded cases.
Conclusion: The unified framework successfully extends qualitative reasoning capabilities while maintaining polynomial satisfiability guarantees, broadening applicability to previously excluded formalisms important for combinations.
Abstract: Among the various forms of reasoning studied in the context of artificial intelligence, qualitative reasoning makes it possible to infer new knowledge in the context of imprecise, incomplete information without numerical values. In this paper, we propose a formal framework unifying several forms of extensions and combinations of qualitative formalisms, including multi-scale reasoning, temporal sequences, and loose integrations. This framework makes it possible to reason in the context of each of these combinations and extensions, but also to study in a unified way the satisfiability decision and its complexity. In particular, we establish two complementary theorems guaranteeing that the satisfiability decision is polynomial, and we use them to recover the known results of the size-topology combination. We also generalize the main definition of qualitative formalism to include qualitative formalisms excluded from the definitions of the literature, important in the context of combinations.
[607] Scalable Delphi: Large Language Models for Structured Risk Estimation
Tobias Lorenz, Mario Fritz
Main category: cs.AI
TL;DR: Scalable Delphi uses LLMs as proxies for expert elicitation in risk assessment, achieving strong correlation with benchmarks and human experts while reducing time from months to minutes.
Details
Motivation: Traditional structured expert elicitation methods like Delphi are time-consuming and resource-intensive, making rigorous risk assessment inaccessible for most applications. The paper aims to investigate whether LLMs can serve as scalable alternatives to overcome these limitations.Method: Proposes Scalable Delphi, adapting classical Delphi protocol for LLMs with diverse expert personas, iterative refinement, and rationale sharing. Evaluates using necessary conditions framework: calibration against verifiable proxies, sensitivity to evidence, and alignment with human expert judgment. Tested in AI-augmented cybersecurity risk domain with three capability benchmarks and independent human elicitation studies.
Result: LLM panels achieve strong correlations with benchmark ground truth (Pearson r=0.87-0.95), improve systematically as evidence is added, and align with human expert panels. In one comparison, LLM panels were closer to a human panel than the two human panels were to each other.
Conclusion: LLM-based elicitation can extend structured expert judgment to settings where traditional methods are infeasible, reducing elicitation time from months to minutes while maintaining quality comparable to human expert panels.
Abstract: Quantitative risk assessment in high-stakes domains relies on structured expert elicitation to estimate unobservable properties. The gold standard - the Delphi method - produces calibrated, auditable judgments but requires months of coordination and specialist time, placing rigorous risk assessment out of reach for most applications. We investigate whether Large Language Models (LLMs) can serve as scalable proxies for structured expert elicitation. We propose Scalable Delphi, adapting the classical protocol for LLMs with diverse expert personas, iterative refinement, and rationale sharing. Because target quantities are typically unobservable, we develop an evaluation framework based on necessary conditions: calibration against verifiable proxies, sensitivity to evidence, and alignment with human expert judgment. We evaluate in the domain of AI-augmented cybersecurity risk, using three capability benchmarks and independent human elicitation studies. LLM panels achieve strong correlations with benchmark ground truth (Pearson r=0.87-0.95), improve systematically as evidence is added, and align with human expert panels - in one comparison, closer to a human panel than the two human panels are to each other. This demonstrates that LLM-based elicitation can extend structured expert judgment to settings where traditional methods are infeasible, reducing elicitation time from months to minutes.
[608] Efficient and Stable Reinforcement Learning for Diffusion Language Models
Jiawei Liu, Xiting Wang, Yuanyuan Zhong, Defu Lian, Yu Yang
Main category: cs.AI
TL;DR: STP (Spatio-Temporal Pruning) improves RL efficiency and stability for diffusion-based LLMs by compressing redundancy through spatial pruning (constraining exploration space) and temporal pruning (bypassing late-stage refinement steps).
Details
Motivation: Applying RL to diffusion-based LLMs faces efficiency and stability challenges due to the complex generative process. Existing methods struggle with redundant computations and unstable policy updates during RL training.Method: Proposes STP framework with two components: spatial pruning uses static priors to constrain exploration space, and temporal pruning bypasses redundant late-stage refinement steps in the diffusion process. Theoretical analysis shows STP reduces variance of log-likelihood estimation.
Result: Extensive experiments show STP surpasses state-of-the-art baselines in both efficiency and accuracy. The method demonstrates improved stability in policy updates and reduced computational overhead.
Conclusion: STP effectively addresses efficiency and stability challenges in RL for diffusion-based LLMs through spatio-temporal pruning, enabling more practical RL applications for complex reasoning tasks.
Abstract: Reinforcement Learning (RL) is crucial for unlocking the complex reasoning capabilities of Diffusion-based Large Language Models (dLLMs). However, applying RL to dLLMs faces unique challenges in efficiency and stability. To address these challenges, we propose Spatio-Temporal Pruning (STP), a framework designed to simultaneously improve the efficiency and stability of RL for dLLMs. STP compresses the redundancy in the generative process through: (1) \textit{spatial pruning}, which constrains the exploration space using static priors; and (2) \textit{temporal pruning}, which bypasses redundant late-stage refinement steps. Our theoretical analysis demonstrates that STP strictly reduces the variance of the log-likelihood estimation, thereby ensuring more stable policy updates. Extensive experiments demonstrate that STP surpasses state-of-the-art baselines in both efficiency and accuracy. Our code is available at https://github.com/Lolo1222/STP.
[609] CausalT5K: Diagnosing and Informing Refusal for Trustworthy Causal Reasoning of Skepticism, Sycophancy, Detection-Correction, and Rung Collapse
Longling Geng, Andy Ouyang, Theodore Wu, Daphne Barretto, Matthew John Hayes, Rachael Cooper, Yuqiao Zeng, Sameer Vijay, Gia Ancone, Ankit Rai, Matthew Wolfman, Patrick Flanagan, Edward Y. Chang
Main category: cs.AI
TL;DR: CausalT5K is a diagnostic benchmark with 5,000+ cases across 10 domains that tests LLMs’ causal reasoning capabilities, specifically detecting rung collapse, resisting sycophantic drift, and generating wise refusals when evidence is underdetermined.
Details
Motivation: Current LLMs exhibit well-documented failures in causal reasoning (sycophancy, rung collapse, miscalibrated refusal), but progress on remediation is slow due to lack of systematic diagnostic benchmarks that can reveal specific failure modes.Method: Developed through human-machine collaborative pipeline with 40 domain experts, iterative cross-validation, and composite verification via rule-based, LLM, and human scoring. Embeds causal traps in realistic narratives and decomposes performance into Utility (sensitivity) and Safety (specificity).
Result: Preliminary experiments reveal a Four-Quadrant Control Landscape where static audit policies universally fail, demonstrating CausalT5K’s value for advancing trustworthy reasoning systems.
Conclusion: CausalT5K provides essential research infrastructure for diagnosing and improving LLMs’ causal reasoning capabilities, enabling systematic remediation of critical failure modes that are invisible to aggregate accuracy metrics.
Abstract: LLM failures in causal reasoning, including sycophancy, rung collapse, and miscalibrated refusal, are well-documented, yet progress on remediation is slow because no benchmark enables systematic diagnosis. We introduce CausalT5K, a diagnostic benchmark of over 5,000 cases across 10 domains that tests three critical capabilities: (1) detecting rung collapse, where models answer interventional queries with associational evidence; (2) resisting sycophantic drift under adversarial pressure; and (3) generating Wise Refusals that specify missing information when evidence is underdetermined. Unlike synthetic benchmarks, CausalT5K embeds causal traps in realistic narratives and decomposes performance into Utility (sensitivity) and Safety (specificity), revealing failure modes invisible to aggregate accuracy. Developed through a rigorous human-machine collaborative pipeline involving 40 domain experts, iterative cross-validation cycles, and composite verification via rule-based, LLM, and human scoring, CausalT5K implements Pearl’s Ladder of Causation as research infrastructure. Preliminary experiments reveal a Four-Quadrant Control Landscape where static audit policies universally fail, a finding that demonstrates CausalT5K’s value for advancing trustworthy reasoning systems. Repository: https://github.com/genglongling/CausalT5kBench
[610] CoRefine: Confidence-Guided Self-Refinement for Adaptive Test-Time Compute
Chen Jin, Ryutaro Tanno, Tom Diethe, Philip Teare
Main category: cs.AI
TL;DR: CoRefine is a confidence-guided self-refinement method that uses a lightweight controller to reduce token usage in LLM reasoning by 190x compared to parallel decoding baselines, achieving competitive accuracy with targeted self-correction.
Details
Motivation: Current LLMs rely on compute-intensive parallel decoding (e.g., 512 samples) for test-time scaling to boost reasoning accuracy, which incurs substantial computational costs. There's a need for more efficient methods that can achieve similar accuracy with significantly reduced token usage.Method: CoRefine uses a 211k-parameter Conv1D controller atop a frozen LLM that consumes full-trace confidence to make decisions: halt, re-examine, or try a different approach. This enables targeted self-correction with an average of 2.7 refinement steps per problem. CoRefine-Tree extends this with a hybrid sequential-parallel variant that adaptively balances exploration and exploitation.
Result: The controller achieves 92.6% precision when confidently halting, indicating confidence dynamics reliably signal correctness without ground-truth verification. It achieves roughly 190-fold token reduction relative to 512-sample baselines while maintaining competitive accuracy across diverse reasoning benchmarks and three open-source models.
Conclusion: By treating confidence as a control signal rather than a correctness guarantee, CoRefine provides a modular primitive for scalable reasoning and agentic settings with imperfect verifiers, offering efficient test-time scaling with easy serving integration and verifier compatibility.
Abstract: Large Language Models (LLMs) often rely on test-time scaling via parallel decoding (for example, 512 samples) to boost reasoning accuracy, but this incurs substantial compute. We introduce CoRefine, a confidence-guided self-refinement method that achieves competitive accuracy using a fraction of the tokens via a lightweight 211k-parameter Conv1D controller atop a frozen LLM. The controller consumes full-trace confidence to decide whether to halt, re-examine, or try a different approach, enabling targeted self-correction with an average of 2.7 refinement steps per problem and roughly 190-fold token reduction relative to 512-sample baselines. Across diverse reasoning benchmarks and three open-source models, the controller achieves 92.6 percent precision when it confidently halts, indicating that confidence dynamics reliably signal correctness without ground-truth verification. We extend this to CoRefine-Tree, a hybrid sequential-parallel variant that adaptively balances exploration and exploitation, with easy serving integration and verifier compatibility. By treating confidence as a control signal rather than a correctness guarantee, CoRefine provides a modular primitive for scalable reasoning and agentic settings with imperfect verifiers.
[611] Digital Twin and Agentic AI for Wild Fire Disaster Management: Intelligent Virtual Situation Room
Mohammad Morsali, Siavash H. Khajavi
Main category: cs.AI
TL;DR: IVSR is an AI-augmented Digital Twin platform for proactive wildfire management using real-time multisource data and autonomous agents to reduce response latency and improve resource coordination.
Details
Motivation: Wildfire frequency and intensity are increasing due to climate change, but conventional disaster management relies on static simulations and passive data acquisition, lacking real-time adaptability to evolving wildfire situations.Method: Intelligent Virtual Situation Room (IVSR) creates a bidirectional Digital Twin platform with autonomous AI agents that continuously ingest multisource sensor imagery, weather data, and 3D forest models. It uses a similarity engine to align conditions with a precomputed Disaster Simulation Library and retrieves/calibrates intervention tactics.
Result: Validation through industrial case-study simulations demonstrates capabilities in localized incident detection, privacy-preserving playback, collider-based fire-spread projection, and site-specific ML retraining. Results show marked reductions in detection-to-intervention latency and more effective resource coordination versus traditional systems.
Conclusion: IVSR offers a scalable, semi-automated decision-support paradigm for proactive, adaptive wildfire disaster management by uniting real-time bidirectional Digital Twins with agentic AI.
Abstract: According to the United Nations, wildfire frequency and intensity are projected to increase by approximately 14% by 2030 and 30% by 2050 due to global warming, posing critical threats to life, infrastructure, and ecosystems. Conventional disaster management frameworks rely on static simulations and passive data acquisition, hindering their ability to adapt to arbitrarily evolving wildfire episodes in real-time. To address these limitations, we introduce the Intelligent Virtual Situation Room (IVSR), a bidirectional Digital Twin (DT) platform augmented by autonomous AI agents. The IVSR continuously ingests multisource sensor imagery, weather data, and 3D forest models to create a live virtual replica of the fire environment. A similarity engine powered by AI aligns emerging conditions with a precomputed Disaster Simulation Library, retrieving and calibrating intervention tactics under the watchful eyes of experts. Authorized action-ranging from UAV redeployment to crew reallocation-is cycled back through standardized procedures to the physical layer, completing the loop between response and analysis. We validate IVSR through detailed case-study simulations provided by an industrial partner, demonstrating capabilities in localized incident detection, privacy-preserving playback, collider-based fire-spread projection, and site-specific ML retraining. Our results indicate marked reductions in detection-to-intervention latency and more effective resource coordination versus traditional systems. By uniting real-time bidirectional DTs with agentic AI, IVSR offers a scalable, semi-automated decision-support paradigm for proactive, adaptive wildfire disaster management.
[612] stable-worldmodel-v1: Reproducible World Modeling Research and Evaluation
Lucas Maes, Quentin Le Lidec, Dan Haramati, Nassim Massaudi, Damien Scieur, Yann LeCun, Randall Balestriero
Main category: cs.AI
TL;DR: SWM is a modular, tested world-model research ecosystem with standardized environments, data tools, and planning algorithms to improve reusability and evaluation standardization.
Details
Motivation: Current world model implementations are publication-specific, limiting reusability, increasing bugs, and reducing evaluation standardization, creating a need for a robust research ecosystem.Method: Developed stable-worldmodel (SWM) - a modular ecosystem with efficient data-collection tools, standardized environments, planning algorithms, baseline implementations, and controllable visual/physical factors of variation.
Result: SWM enables controllable factors of variation for robustness research and was used to study zero-shot robustness in DINO-WM, demonstrating its utility.
Conclusion: SWM addresses critical limitations in world model research by providing a reusable, tested ecosystem that supports robustness and continual learning research through standardized tools and environments.
Abstract: World Models have emerged as a powerful paradigm for learning compact, predictive representations of environment dynamics, enabling agents to reason, plan, and generalize beyond direct experience. Despite recent interest in World Models, most available implementations remain publication-specific, severely limiting their reusability, increasing the risk of bugs, and reducing evaluation standardization. To mitigate these issues, we introduce stable-worldmodel (SWM), a modular, tested, and documented world-model research ecosystem that provides efficient data-collection tools, standardized environments, planning algorithms, and baseline implementations. In addition, each environment in SWM enables controllable factors of variation, including visual and physical properties, to support robustness and continual learning research. Finally, we demonstrate the utility of SWM by using it to study zero-shot robustness in DINO-WM.
[613] InternAgent-1.5: A Unified Agentic Framework for Long-Horizon Autonomous Scientific Discovery
Shiyang Feng, Runmin Ma, Xiangchao Yan, Yue Fan, Yusong Hu, Songtao Huang, Shuaiyu Zhang, Zongsheng Cao, Tianshuo Peng, Jiakang Yuan, Zijie Guo, Zhijie Zhong, Shangheng Du, Weida Wang, Jinxin Shi, Yuhao Zhou, Xiaohan He, Zhiyin Yu, Fangchen Yu, Qihao Zheng, Jiamin Wu, Mianxin Liu, Chi Zhang, Shaowei Hou, Shuya Li, Yankai Jiang, Wenjie Lou, Lilong Wang, Zifu Wang, Jiong Wang, Wanghan Xu, Yue Deng, Dongrui Liu, Yiheng Wang, Wenlong Zhang, Fenghua Ling, Shufei Zhang, Xiaosong Wang, Shuangjia Zheng, Xun Huang, Siqi Sun, Shuyue Hu, Peng Ye, Chunfeng Song, Bin Wang, Conghui He, Yihao Liu, Xin Li, Qibin Hou, Tao Chen, Xiangyu Yue, Bin Wang, Liang He, Dahua Lin, Bowen Zhou, Bo Zhang, Lei Bai
Main category: cs.AI
TL;DR: InternAgent-1.5 is a unified autonomous scientific discovery system with coordinated subsystems for generation, verification, and evolution, capable of both computational modeling and laboratory experimentation across various scientific domains.
Details
Motivation: To create a general and scalable framework for end-to-end autonomous scientific discovery that can operate across both computational and empirical domains, coordinating modeling and experimentation within a single system.Method: Structured architecture with three coordinated subsystems (generation, verification, evolution) supported by foundational capabilities for deep research, solution optimization, and long horizon memory, enabling continuous operation across extended discovery cycles.
Result: Achieves leading performance on scientific reasoning benchmarks (GAIA, HLE, GPQA, FrontierScience) and demonstrates autonomous discovery capabilities in algorithm design for ML problems and empirical experiments in earth, life, biological, and physical domains.
Conclusion: InternAgent-1.5 provides a general and scalable framework for autonomous scientific discovery that can coordinate computational modeling and laboratory experimentation within a unified system.
Abstract: We introduce InternAgent-1.5, a unified system designed for end-to-end scientific discovery across computational and empirical domains. The system is built on a structured architecture composed of three coordinated subsystems for generation, verification, and evolution. These subsystems are supported by foundational capabilities for deep research, solution optimization, and long horizon memory. The architecture allows InternAgent-1.5 to operate continuously across extended discovery cycles while maintaining coherent and improving behavior. It also enables the system to coordinate computational modeling and laboratory experimentation within a single unified system. We evaluate InternAgent-1.5 on scientific reasoning benchmarks such as GAIA, HLE, GPQA, and FrontierScience, and the system achieves leading performance that demonstrates strong foundational capabilities. Beyond these benchmarks, we further assess two categories of discovery tasks. In algorithm discovery tasks, InternAgent-1.5 autonomously designs competitive methods for core machine learning problems. In empirical discovery tasks, it executes complete computational or wet lab experiments and produces scientific findings in earth, life, biological, and physical domains. Overall, these results show that InternAgent-1.5 provides a general and scalable framework for autonomous scientific discovery.
[614] iGRPO: Self-Feedback-Driven LLM Reasoning
Ali Hatamizadeh, Shrimai Prabhumoye, Igor Gitman, Ximing Lu, Seungju Han, Wei Ping, Yejin Choi, Jan Kautz
Main category: cs.AI
TL;DR: iGRPO is a two-stage RL method that improves mathematical reasoning in LLMs through iterative self-conditioning with model-generated drafts and group-relative reward normalization.
Details
Motivation: LLMs struggle with accurate mathematical reasoning despite their capabilities. Current RL methods like PPO and GRPO help align models with task rewards, but there's room for improvement through iterative self-feedback mechanisms that allow models to learn from their own best attempts.Method: iGRPO extends GRPO with two stages: 1) Sample multiple exploratory drafts and select the highest-reward draft using the same scalar reward signal; 2) Append this best draft to the original prompt and apply GRPO-style updates on draft-conditioned refinements, training the policy to improve beyond its strongest prior attempt.
Result: iGRPO consistently outperforms GRPO across base models (Nemotron-H-8B-Base-8K and DeepSeek-R1 Distilled) and achieves new SOTA results of 85.62% on AIME24 and 79.64% on AIME25 when applied to OpenReasoning-Nemotron-7B trained on AceReason-Math.
Conclusion: Iterative, self-feedback-based RL shows strong potential for advancing verifiable mathematical reasoning in LLMs, with iGRPO’s refinement approach generalizing beyond GRPO variants and benefiting from generative judges while altering learning dynamics.
Abstract: Large Language Models (LLMs) have shown promise in solving complex mathematical problems, yet they still fall short of producing accurate and consistent solutions. Reinforcement Learning (RL) is a framework for aligning these models with task-specific rewards, improving overall quality and reliability. Group Relative Policy Optimization (GRPO) is an efficient, value-function-free alternative to Proximal Policy Optimization (PPO) that leverages group-relative reward normalization. We introduce Iterative Group Relative Policy Optimization (iGRPO), a two-stage extension of GRPO that adds dynamic self-conditioning through model-generated drafts. In Stage 1, iGRPO samples multiple exploratory drafts and selects the highest-reward draft using the same scalar reward signal used for optimization. In Stage 2, it appends this best draft to the original prompt and applies a GRPO-style update on draft-conditioned refinements, training the policy to improve beyond its strongest prior attempt. Under matched rollout budgets, iGRPO consistently outperforms GRPO across base models (e.g., Nemotron-H-8B-Base-8K and DeepSeek-R1 Distilled), validating its effectiveness on diverse reasoning benchmarks. Moreover, applying iGRPO to OpenReasoning-Nemotron-7B trained on AceReason-Math achieves new state-of-the-art results of 85.62% and 79.64% on AIME24 and AIME25, respectively. Ablations further show that the refinement wrapper generalizes beyond GRPO variants, benefits from a generative judge, and alters learning dynamics by delaying entropy collapse. These results underscore the potential of iterative, self-feedback-based RL for advancing verifiable mathematical reasoning.
[615] Data Science and Technology Towards AGI Part I: Tiered Data Management
Yudong Wang, Zixuan Fu, Hengyu Zhao, Chen Zhao, Chuyue Zhou, Xinle Lin, Hongya Lyu, Shuaikang Xue, Yi Yi, Yingjiao Wang, Zhi Zheng, Yuzhou Zhang, Jie Zhou, Chaojun Xiao, Xu Han, Zhiyuan Liu, Maosong Sun
Main category: cs.AI
TL;DR: Proposes a tiered data management framework (L0-L4) for LLM training where models actively guide data management and high-quality data amplifies model capabilities, moving beyond simple data scaling to data-model co-evolution.
Details
Motivation: Current LLM research faces bottlenecks in data availability, acquisition cost, and training efficiency due to reliance on unidirectional scaling of data size. The paper argues AGI development needs a new phase of data-model co-evolution where models actively guide data management while high-quality data amplifies model capabilities.Method: Introduces an L0-L4 tiered data management framework ranging from raw uncurated resources to organized and verifiable knowledge. LLMs are used in data management processes (quality scoring, content editing) to refine data across tiers. Each tier has distinct properties, management strategies, and training roles, enabling strategic data allocation across pre-training, mid-training, and alignment phases.
Result: Experimental results demonstrate that tier-aware data utilization significantly improves training efficiency and model performance. The framework balances data quality, acquisition cost, and marginal training benefit, providing systematic approach to scalable and sustainable data management.
Conclusion: The proposed tiered data management framework enables more efficient and effective LLM training through data-model co-evolution, addressing current bottlenecks in data scaling approaches. The framework and tools are released to the community to facilitate further research.
Abstract: The development of artificial intelligence can be viewed as an evolution of data-driven learning paradigms, with successive shifts in data organization and utilization continuously driving advances in model capability. Current LLM research is dominated by a paradigm that relies heavily on unidirectional scaling of data size, increasingly encountering bottlenecks in data availability, acquisition cost, and training efficiency. In this work, we argue that the development of AGI is entering a new phase of data-model co-evolution, in which models actively guide data management while high-quality data, in turn, amplifies model capabilities. To implement this vision, we propose a tiered data management framework, designed to support the full LLM training lifecycle across heterogeneous learning objectives and cost constraints. Specifically, we introduce an L0-L4 tiered data management framework, ranging from raw uncurated resources to organized and verifiable knowledge. Importantly, LLMs are fully used in data management processes, such as quality scoring and content editing, to refine data across tiers. Each tier is characterized by distinct data properties, management strategies, and training roles, enabling data to be strategically allocated across LLM training stages, including pre-training, mid-training, and alignment. The framework balances data quality, acquisition cost, and marginal training benefit, providing a systematic approach to scalable and sustainable data management. We validate the effectiveness of the proposed framework through empirical studies, in which tiered datasets are constructed from raw corpora and used across multiple training phases. Experimental results demonstrate that tier-aware data utilization significantly improves training efficiency and model performance. To facilitate further research, we release our tiered datasets and processing tools to the community.
[616] GEBench: Benchmarking Image Generation Models as GUI Environments
Haodong Li, Jingwei Wu, Quan Sun, Guopeng Li, Juanxi Tian, Huanyu Zhang, Yanlin Lai, Ruichuan An, Hongbo Peng, Yuhong Dai, Chenxi Li, Chunmei Qing, Jia Wang, Ziyang Meng, Zheng Ge, Xiangyu Zhang, Daxin Jiang
Main category: cs.AI
TL;DR: GEBench is a benchmark for evaluating dynamic GUI state generation and temporal coherence, with a novel 5D metric (GE-Score) covering goal achievement, interaction logic, content consistency, UI plausibility, and visual quality.
Details
Motivation: Existing benchmarks focus on general visual fidelity but lack evaluation of state transitions and temporal coherence in GUI-specific contexts, creating a gap for assessing dynamic interaction in GUI generation.Method: Created GEBench with 700 curated samples across 5 task categories covering single-step and multi-step interactions, plus grounding point localization. Developed GE-Score, a 5-dimensional metric for systematic evaluation.
Result: Current models perform well on single-step transitions but struggle significantly with maintaining temporal coherence and spatial grounding over longer sequences. Icon interpretation, text rendering, and localization precision are identified as critical bottlenecks.
Conclusion: GEBench provides a foundation for systematic assessment of dynamic GUI generation and suggests directions for future research toward building high-fidelity generative GUI environments.
Abstract: Recent advancements in image generation models have enabled the prediction of future Graphical User Interface (GUI) states based on user instructions. However, existing benchmarks primarily focus on general domain visual fidelity, leaving the evaluation of state transitions and temporal coherence in GUI-specific contexts underexplored. To address this gap, we introduce GEBench, a comprehensive benchmark for evaluating dynamic interaction and temporal coherence in GUI generation. GEBench comprises 700 carefully curated samples spanning five task categories, covering both single-step interactions and multi-step trajectories across real-world and fictional scenarios, as well as grounding point localization. To support systematic evaluation, we propose GE-Score, a novel five-dimensional metric that assesses Goal Achievement, Interaction Logic, Content Consistency, UI Plausibility, and Visual Quality. Extensive evaluations on current models indicate that while they perform well on single-step transitions, they struggle significantly with maintaining temporal coherence and spatial grounding over longer interaction sequences. Our findings identify icon interpretation, text rendering, and localization precision as critical bottlenecks. This work provides a foundation for systematic assessment and suggests promising directions for future research toward building high-fidelity generative GUI environments. The code is available at: https://github.com/stepfun-ai/GEBench.
[617] Tree Search for Language Model Agents
Jing Yu Koh, Stephen McAleer, Daniel Fried, Ruslan Salakhutdinov
Main category: cs.AI
TL;DR: Tree search algorithm for LM agents improves web automation performance through explicit exploration and multi-step planning in interactive environments.
Details
Motivation: Current LM agents struggle with multi-step reasoning, planning, and using environmental feedback for realistic computer tasks, despite their promise in decision-making tasks like web automation.Method: Proposes an inference-time best-first tree search algorithm that operates within actual environment space, enabling explicit exploration and multi-step planning for LM agents in interactive web environments.
Result: On VisualWebArena: 39.7% relative increase in success rate over GPT-4o baseline, achieving SOTA 26.4%. On WebArena: 28.0% relative improvement, achieving competitive 19.2% success rate. Performance scales with increased test-time compute.
Conclusion: Search algorithms significantly improve LM agent performance on web tasks, demonstrating effectiveness of explicit exploration and planning. Future work should address remaining limitations and build on these promising results.
Abstract: Autonomous agents powered by language models (LMs) have demonstrated promise in their ability to perform decision-making tasks such as web automation. However, a key limitation remains: LMs, primarily optimized for natural language understanding and generation, struggle with multi-step reasoning, planning, and using environmental feedback when attempting to solve realistic computer tasks. Towards addressing this, we propose an inference-time search algorithm for LM agents to explicitly perform exploration and multi-step planning in interactive web environments. Our approach is a form of best-first tree search that operates within the actual environment space, and is complementary with most existing state-of-the-art agents. It is the first tree search algorithm for LM agents that shows effectiveness on realistic web tasks. On the challenging VisualWebArena benchmark, applying our search algorithm on top of a GPT-4o agent yields a 39.7% relative increase in success rate compared to the same baseline without search, setting a state-of-the-art success rate of 26.4%. On WebArena, search also yields a 28.0% relative improvement over a baseline agent, setting a competitive success rate of 19.2%. Our experiments highlight the effectiveness of search for web agents, and we demonstrate that performance scales with increased test-time compute. We conduct a thorough analysis of our results to highlight improvements from search, limitations, and promising directions for future work. Our code and models are publicly released at https://jykoh.com/search-agents.
[618] Nondeterministic Polynomial-time Problem Challenge: An Ever-Scaling Reasoning Benchmark for LLMs
Chang Yang, Ruiyu Wang, Junzhe Jiang, Qi Jiang, Qinggang Zhang, Yanchen Deng, Shuxin Li, Shuyue Hu, Bo Li, Florian T. Pokorny, Xiao Huang, Xinrun Wang
Main category: cs.AI
TL;DR: NPPC is an ever-scaling reasoning benchmark for LLMs based on NP-complete problems, designed to resist quick crushing and hacking through complexity scaling and instance generation.
Details
Motivation: Current reasoning benchmarks for LLMs are quickly crushed (within 1 year) and easily hacked, necessitating a more robust, scalable benchmark that can withstand rapid model improvements.Method: NPPC consists of three modules: npgym (25 NP-complete problems with scalable complexity), npsolver (unified evaluation interface for online/offline models), and npeval (comprehensive analysis tools for performance, tokens, and errors).
Result: NPPC reduces advanced LLM performance below 10%, showing it’s not crushed by current models; identifies top-performing models (DeepSeek-R1, Claude-3.7-Sonnet, o1/o3-mini); reveals token usage patterns that first increase then decrease with difficulty.
Conclusion: NPPC provides critical insights into LLM reasoning limits, exposes fundamental limitations, and suggests future directions through continuous scaling analysis of NP-complete problems.
Abstract: Reasoning is the fundamental capability of large language models (LLMs). Due to the rapid progress of LLMs, there are two main issues of current benchmarks: i) these benchmarks can be crushed in a short time (less than 1 year), and ii) these benchmarks may be easily hacked. To handle these issues, we propose the ever-scalingness for building the benchmarks which are scaling over complexity against crushing, instance against hacking and exploitation, oversight for easy verification, and coverage for real-world relevance. This paper presents Nondeterministic Polynomial-time Problem Challenge (NPPC), an ever-scaling reasoning benchmark for LLMs. Specifically, the NPPC has three main modules: i) npgym, which provides a unified interface of 25 well-known NP-complete problems and can generate any number of instances with any levels of complexities, ii) npsolver, which provides a unified interface to evaluate the problem instances with both online and offline models via APIs and local deployments, respectively, and iii) npeval, which provides the comprehensive and ready-to-use tools to analyze the performances of LLMs over different problems, the number of tokens, the reasoning errors and the solution errors. Extensive experiments over widely-used LLMs demonstrate: i) NPPC can successfully decrease the performances of advanced LLMs to below 10%, demonstrating that NPPC is not crushed by current models, ii) DeepSeek-R1, Claude-3.7-Sonnet, and o1/o3-mini are the most powerful LLMs, and iii) the numbers of tokens in the advanced LLMs, e.g., Claude-3.7-Sonnet and DeepSeek-R1, are observed first to increase and then decrease when the problem instances become more and more difficult. Through continuously scaling analysis, NPPC can provide critical insights into the limits of LLMs’ reasoning capabilities, exposing fundamental limitations and suggesting future directions for further improvements.
[619] Capability-Based Scaling Trends for LLM-Based Red-Teaming
Alexander Panfilov, Paul Kassianik, Maksym Andriushchenko, Jonas Geiping
Main category: cs.AI
TL;DR: The paper studies jailbreak attacks on large language models through the lens of capability gaps between attackers and targets, finding that attack success drops sharply when targets surpass attackers in capability, and that more capable models make better attackers.
Details
Motivation: As LLMs grow in capability and agency, identifying vulnerabilities through red-teaming becomes vital for safe deployment. Traditional prompt-engineering approaches may become ineffective when red-teaming becomes a weak-to-strong problem where target models surpass red-teamers in capabilities.Method: Framed red-teaming through the lens of capability gap between attacker and target. Evaluated over 600 attacker-target pairs using LLM-based jailbreak attacks that mimic human red-teamers across diverse families, sizes, and capability levels.
Result: Three strong trends emerged: (1) more capable models are better attackers, (2) attack success drops sharply once target’s capability exceeds attacker’s, and (3) attack success rates correlate with high performance on social science splits of MMLU-Pro benchmark. Derived a jailbreaking scaling curve that predicts attack success based on attacker-target capability gap.
Conclusion: Fixed-capability attackers (e.g., humans) may become ineffective against future models, increasingly capable open-source models amplify risks for existing systems, and model providers must accurately measure and control models’ persuasive and manipulative abilities to limit their effectiveness as attackers.
Abstract: As large language models grow in capability and agency, identifying vulnerabilities through red-teaming becomes vital for safe deployment. However, traditional prompt-engineering approaches may prove ineffective once red-teaming turns into a \emph{weak-to-strong} problem, where target models surpass red-teamers in capabilities. To study this shift, we frame red-teaming through the lens of the \emph{capability gap} between attacker and target. We evaluate more than 600 attacker-target pairs using LLM-based jailbreak attacks that mimic human red-teamers across diverse families, sizes, and capability levels. Three strong trends emerge: (i) more capable models are better attackers, (ii) attack success drops sharply once the target’s capability exceeds the attacker’s, and (iii) attack success rates correlate with high performance on social science splits of the MMLU-Pro benchmark. From these observations, we derive a \emph{jailbreaking scaling curve} that predicts attack success for a fixed target based on attacker-target capability gap. These findings suggest that fixed-capability attackers (e.g., humans) may become ineffective against future models, increasingly capable open-source models amplify risks for existing systems, and model providers must accurately measure and control models’ persuasive and manipulative abilities to limit their effectiveness as attackers.
[620] Certainty-Guided Reasoning in Large Language Models: A Dynamic Thinking Budget Approach
João Paulo Nogueira, Wentao Sun, Alonso Silva, Laith Zumot
Main category: cs.AI
TL;DR: CGR is an adaptive inference method that uses certainty estimation to terminate reasoning early when confident, reducing computation while maintaining accuracy.
Details
Motivation: Current large reasoning models use fixed inference budgets, which can waste computation or cut reasoning short prematurely. There's a need for adaptive methods that can dynamically adjust reasoning length based on confidence.Method: CGR periodically probes the model’s certainty by examining predicted probabilities over answer tokens. It terminates early when a target certainty threshold is reached, otherwise continues until end-of-thinking token or budget limit.
Result: On AIME2025, CGR preserves baseline accuracy while reducing token usage, providing tunable certainty-efficiency trade-off. Across 64 random seeds, CGR exhibits consistent behavior. The Grade metric shows CGR improves performance by abstaining when certainty remains low.
Conclusion: CGR offers an effective adaptive inference approach that balances computational efficiency with reasoning quality through certainty-guided early termination.
Abstract: Large reasoning language models are typically run with fixed inference budgets, which can waste computation or terminate reasoning prematurely. We introduce Certainty-Guided Reasoning (CGR), a model-agnostic adaptive inference procedure that periodically probes whether the current reasoning supports a confident final answer and terminates early once a target certainty threshold is reached, otherwise continuing until the end-of-thinking token or the budget limit. Certainty is estimated from the model’s predicted probabilities over the answer tokens, yielding a lightweight stopping criterion. On AIME2025, CGR preserves baseline accuracy while reducing token usage, providing a tunable certainty-efficiency trade-off that can eliminate millions of tokens in aggregate. Across 64 random seeds, CGR exhibits consistent behavior. We also introduce a Grade metric that penalizes incorrect answers and permits abstention, capturing risk-sensitive performance. Results show that CGR improves Grade by abstaining when certainty remains low.
[621] Knowledge-Centric Metacognitive Learning
Arun Kumar, Paul Schrater
Main category: cs.AI
TL;DR: Knowledge-centric metacognitive learning framework that integrates abstract knowledge into reinforcement learning through natural abstractions, knowledge-guided interactions, and composition of interactions for problem solving.
Details
Motivation: Current AI systems lack principled mechanisms for incorporating abstract knowledge into learning, which limits their ability to adapt to novel situations and develop intelligent, adaptive behavior like humans do.Method: Introduces three key principles: 1) natural abstractions, 2) knowledge-guided interactions through interpretation, and 3) composition of interactions for problem solving. The framework facilitates acquisition of abstract knowledge and associates interactions with knowledge, enabling transferable interaction concepts.
Result: The metacognitive mechanism provides a principled approach for integrating knowledge into reinforcement learning, enabling abstract reasoning, generalization, and learning of transferable interaction concepts.
Conclusion: This knowledge-centric metacognitive learning offers a promising pathway toward intelligent and adaptive behavior in artificial intelligence, robotics, and autonomous systems by bridging the gap between abstract knowledge and interactive learning.
Abstract: Interactions are central to intelligent reasoning and learning abilities, with the interpretation of abstract knowledge guiding meaningful interaction with objects in the environment. While humans readily adapt to novel situations by leveraging abstract knowledge acquired over time, artificial intelligence systems lack principled mechanisms for incorporating abstract knowledge into learning, leading to fundamental challenges in the emergence of intelligent and adaptive behavior. To address this gap, we introduce knowledge-centric metacognitive learning based on three key principles: natural abstractions, knowledge-guided interactions through interpretation, and the composition of interactions for problem solving. Knowledge learning facilitates the acquisition of abstract knowledge and the association of interactions with knowledge, while object interactions guided by abstract knowledge enable the learning of transferable interaction concepts, abstract reasoning, and generalization. This metacognitive mechanism provides a principled approach for integrating knowledge into reinforcement learning and offers a promising pathway toward intelligent and adaptive behavior in artificial intelligence, robotics, and autonomous systems.
[622] Generative AI voting: fair collective choice is resilient to LLM biases and inconsistencies
Srijoni Majumdar, Edith Elkind, Evangelos Pournaras
Main category: cs.AI
TL;DR: AI personal assistants using LLMs can represent abstained voters in elections, but their biases affect collective decisions; proportional voting methods like equal shares produce fairer outcomes for both humans and AI representation.
Details
Motivation: To investigate how LLM-based AI personal assistants can represent abstained voters in democratic elections, and to understand what biases manifest when delegating collective decision-making to LLMs, which is a timely challenge for democratic resilience.Method: Rigorous emulation of over 50K LLM voting personas in 363 real-world voting elections, analyzing how AI-generated choices differ from human choices and how this affects collective decision outcomes across different ballot formats.
Result: Complex preferential ballot formats show significant inconsistencies compared to simpler majoritarian elections; proportional ballot aggregation methods like equal shares prove to be a win-win, producing fairer voting outcomes for both humans and AI representation, especially for voters likely to abstain.
Conclusion: Proportional voting methods can help build democratic resilience in low voter turnout scenarios by using AI representatives to recover representative and fair voting outcomes, providing insights for policymakers developing safeguards for AI use in democratic innovations.
Abstract: Recent breakthroughs in generative artificial intelligence (AI) and large language models (LLMs) unravel new capabilities for AI personal assistants to overcome cognitive bandwidth limitations of humans, providing decision support or even direct representation of abstained human voters at large scale. However, the quality of this representation and what underlying biases manifest when delegating collective decision making to LLMs is an alarming and timely challenge to tackle. By rigorously emulating more than >50K LLM voting personas in 363 real-world voting elections, we disentangle how AI-generated choices differ from human choices and how this affects collective decision outcomes. Complex preferential ballot formats show significant inconsistencies compared to simpler majoritarian elections, which demonstrate higher consistency. Strikingly, proportional ballot aggregation methods such as equal shares prove to be a win-win: fairer voting outcomes for humans and fairer AI representation, especially for voters likely to abstain. This novel underlying relationship proves paramount for building democratic resilience in scenarios of low voters turnout by voter fatigue: abstained voters are mitigated via AI representatives that recover representative and fair voting outcomes. These interdisciplinary insights provide decision support to policymakers and citizens for developing safeguards and policies for risks of using AI in democratic innovations.
[623] BEAT: Visual Backdoor Attacks on VLM-based Embodied Agents via Contrastive Trigger Learning
Qiusi Zhan, Hyeonjeong Ha, Rui Yang, Sirui Xu, Hanyang Chen, Liang-Yan Gui, Yu-Xiong Wang, Huan Zhang, Heng Ji, Daniel Kang
Main category: cs.AI
TL;DR: BEAT framework injects visual backdoors into VLM-based embodied agents using environmental objects as triggers, achieving high attack success while maintaining normal task performance.
Details
Motivation: Vision-Language Models enable embodied agents for perception and planning, but create new security vulnerabilities through visual backdoor attacks where agents behave normally until triggered by specific objects, then execute attacker-specified policies.Method: BEAT uses a two-stage training: (1) supervised fine-tuning on diverse scenes, tasks, and trigger placements, and (2) Contrastive Trigger Learning that formulates trigger discrimination as preference learning between trigger-present and trigger-free inputs to sharpen decision boundaries.
Result: BEAT achieves up to 80% attack success rates across various embodied agent benchmarks and VLMs while maintaining strong benign task performance, and generalizes to out-of-distribution trigger placements. CTL boosts backdoor activation accuracy up to 39% compared to naive SFT.
Conclusion: The research exposes critical security risks in VLM-based embodied agents through visual backdoor attacks, highlighting the need for robust defenses before real-world deployment.
Abstract: Recent advances in Vision-Language Models (VLMs) have propelled embodied agents by enabling direct perception, reasoning, and planning task-oriented actions from visual inputs. However, such vision-driven embodied agents open a new attack surface: visual backdoor attacks, where the agent behaves normally until a visual trigger appears in the scene, then persistently executes an attacker-specified multi-step policy. We introduce BEAT, the first framework to inject such visual backdoors into VLM-based embodied agents using objects in the environments as triggers. Unlike textual triggers, object triggers exhibit wide variation across viewpoints and lighting, making them difficult to implant reliably. BEAT addresses this challenge by (1) constructing a training set that spans diverse scenes, tasks, and trigger placements to expose agents to trigger variability, and (2) introducing a two-stage training scheme that first applies supervised fine-tuning (SFT) and then our novel Contrastive Trigger Learning (CTL). CTL formulates trigger discrimination as preference learning between trigger-present and trigger-free inputs, explicitly sharpening the decision boundaries to ensure precise backdoor activation. Across various embodied agent benchmarks and VLMs, BEAT achieves attack success rates up to 80%, while maintaining strong benign task performance, and generalizes reliably to out-of-distribution trigger placements. Notably, compared to naive SFT, CTL boosts backdoor activation accuracy up to 39% under limited backdoor data. These findings expose a critical yet unexplored security risk in VLM-based embodied agents, underscoring the need for robust defenses before real-world deployment.
[624] Revisiting Privacy, Utility, and Efficiency Trade-offs when Fine-Tuning Large Language Models
Soumi Das, Camila Kolling, Mohammad Aflah Khan, Mahsa Amani, Bishwamittra Ghosh, Qinyuan Wu, Till Speicher, Krishna P. Gummadi
Main category: cs.AI
TL;DR: Efficient fine-tuning methods like LoRA provide similar privacy protection as differential privacy methods, challenging the conventional trade-off between privacy and efficiency in LLM fine-tuning.
Details
Motivation: There's a gap in understanding whether parameter-efficient fine-tuning methods (like LoRA) enhance or diminish privacy risks compared to differentially private methods, with conventional wisdom suggesting privacy and efficiency are conflicting objectives.Method: Defined measures of privacy and utility distinguishing between memorizing sensitive vs non-sensitive tokens, then conducted extensive evaluations using multiple open-source LLMs (Pythia, Gemma, Llama, Qwen) and domain-specific datasets.
Result: Surprising finding: efficient fine-tuning methods like LoRA mitigate privacy risks similar to private fine-tuning methods like DP, contradicting the prevailing wisdom that privacy and efficiency are at odds.
Conclusion: Parameter-efficient fine-tuning methods can provide both computational efficiency and privacy protection simultaneously, offering a practical solution for privacy-preserving LLM fine-tuning.
Abstract: We study the inherent trade-offs in minimizing privacy risks and maximizing utility, while maintaining high computational efficiency, when fine-tuning large language models (LLMs). A number of recent works in privacy research have attempted to mitigate privacy risks posed by memorizing fine-tuning data by using differentially private training methods (e.g., DP), albeit at a significantly higher computational cost (inefficiency). In parallel, several works in systems research have focussed on developing (parameter) efficient fine-tuning methods (e.g., LoRA), but few works, if any, investigated whether such efficient methods enhance or diminish privacy risks. In this paper, we investigate this gap and arrive at a surprising conclusion: efficient fine-tuning methods like LoRA mitigate privacy risks similar to private fine-tuning methods like DP. Our empirical finding directly contradicts prevailing wisdom that privacy and efficiency objectives are at odds during fine-tuning. Our finding is established by (a) carefully defining measures of privacy and utility that distinguish between memorizing sensitive and non-sensitive tokens in training and test datasets used in fine-tuning and (b) extensive evaluations using multiple open-source language models from Pythia, Gemma, Llama, and Qwen families and different domain-specific datasets.
[625] Research Superalignment Should Advance Now with Alternating Competence and Conformity Optimization
HyunJin Kim, Xiaoyuan Yi, Jing Yao, Muhua Huang, JinYeong Bak, James Evans, Xing Xie
Main category: cs.AI
TL;DR: Position paper arguing that superalignment (aligning Artificial Superintelligence with human values) is achievable and research should advance immediately through simultaneous optimization of task competence and value conformity.
Details
Motivation: The rapid advancement of AI capabilities raises concerns about aligning potential Artificial Superintelligence (ASI) with human values to ensure it benefits rather than harms humanity, addressing the Superalignment problem.Method: Provides a formal definition of superalignment based on capability-capacity gap, analyzes limitations of existing paradigms, and proposes a conceptual path centered on two fundamental principles: simultaneous and alternating optimization of task competence and value conformity.
Result: The paper presents a theoretical framework arguing that superalignment is achievable and necessary for responsible ASI development, proposing it as a potential initiative for value-aligned next-generation AI.
Conclusion: Superalignment research should advance immediately as it’s both achievable and necessary for responsible ASI development, framing a path toward value-aligned next-generation AI that benefits humanity.
Abstract: The recent leap in AI capabilities, driven by big generative models, has sparked the possibility of achieving Artificial General Intelligence (AGI) and further triggered discussions on Artificial Superintelligence (ASI)-a system surpassing all humans across measured domains. This gives rise to the critical research question of: As we approach ASI, how do we align it with human values, ensuring it benefits rather than harms human society, a.k.a., the Superalignment problem. Despite ASI being regarded by many as a hypothetical concept, in this position paper, we argue that superalignment is achievable and research on it should advance immediately, through simultaneous and alternating optimization of task competence and value conformity. We posit that superalignment is not merely a safeguard for ASI but also necessary for its responsible realization. To support this position, we first provide a formal definition of superalignment rooted in the gap between capability and capacity, delve into its perceived infeasibility by analyzing the limitations of existing paradigms, and then illustrate a conceptual path of superalignment to support its achievability, centered on two fundamental principles. This work frames a potential initiative for developing value-aligned next-generation AI in the future, which will garner greater benefits and reduce potential harm to humanity.
[626] DRAGON: Domain-specific Robust Automatic Data Generation for RAG Optimization
Haiyang Shen, Hang Yan, Zhongshi Xing, Mugeng Liu, Yue Li, Zhiyang Chen, Yuxiang Wang, Jiuzheng Wang, Yun Ma
Main category: cs.AI
TL;DR: DRAGON framework improves domain-specific retrieval for RAG systems through synthetic data generation and a new benchmark for evaluation.
Details
Motivation: Existing RAG systems rely on retrievers trained on public knowledge, which perform poorly on domain-specific queries. There's a need for better domain-specific retrieval capabilities.Method: Proposes DRAGON framework with data-construction modeling and scalable synthetic data generation pipeline. Creates DRAGONBench benchmark with 8 domain-specific document collections across 4 fields. Generates large-scale synthetic dataset with single-hop and multi-hop queries for retriever training.
Result: Retrievers trained on DRAGON-generated data show significant performance gains and strong cross-domain generalization. When integrated into vanilla, planning-based, and iterative RAG paradigms, they yield consistent end-to-end improvements in system accuracy.
Conclusion: DRAGON effectively addresses domain-specific retrieval limitations in RAG systems through synthetic data generation and comprehensive benchmarking, leading to improved performance across multiple RAG paradigms.
Abstract: Retrieval-augmented generation (RAG) can substantially enhance the performance of LLMs on knowledge-intensive tasks. Various RAG paradigms - including vanilla, planning-based, and iterative RAG - all depend on a robust retriever, yet existing retrievers rely heavily on public knowledge and often falter when faced with domain-specific queries. To address these limitations, we introduce DRAGON, a framework that combines a data-construction modeling approach with a scalable synthetic data-generation pipeline, specifically designed to optimize domain-specific retrieval performance and bolster retriever robustness. To evaluate RAG performance on domain-specific RAGs, we propose DRAGONBench, a benchmark spanning 8 domain-specific document collections across 4 distinct fields and featuring a wide spectrum of query complexities, answerability, and hop numbers. Leveraging DRAGON, we generate a large-scale synthetic dataset - encompassing both single-hop and multi-hop queries - to enrich retriever training. Extensive experiments demonstrate that retrievers trained on this data yield significant performance gains and exhibit strong cross-domain generalization. Moreover, when our optimized retrievers are integrated into vanilla, planning-based, and iterative RAG paradigms, we observe consistent end-to-end improvements in system accuracy.
[627] Average Reward Reinforcement Learning for Omega-Regular and Mean-Payoff Objectives
Milad Kazemi, Mateo Perez, Fabio Somenzi, Sadegh Soudjani, Ashutosh Trivedi, Alvaro Velasquez
Main category: cs.AI
TL;DR: First model-free RL framework for absolute liveness specifications in continuing tasks using average-reward objectives, enabling learning in unknown communicating MDPs without episodic resets.
Details
Motivation: Manual reward design is tedious and error-prone. Formal specifications in ω-regular languages are natural but existing episodic RL approaches with discounted rewards are misaligned with ω-regular semantics over infinite traces. Continuing tasks require average-reward criterion for proper alignment.Method: Translates absolute liveness specifications into average-reward objectives for model-free RL in unknown communicating MDPs without episodic resetting. Introduces lexicographic multi-objective optimization: first maximize satisfaction probability of absolute liveness specification, then maximize external average-reward objective.
Result: Method guarantees convergence in unknown communicating MDPs and supports on-the-fly reductions without full environment knowledge. Experiments show continuing average-reward approach outperforms competing discount-based methods across several benchmarks.
Conclusion: Provides principled framework for formal specification-driven RL in continuing tasks, aligning ω-regular semantics with appropriate average-reward objectives and enabling model-free learning without episodic resets.
Abstract: Recent advances in reinforcement learning (RL) have renewed interest in reward design for shaping agent behavior, but manually crafting reward functions is tedious and error-prone. A principled alternative is to specify behavioral requirements in a formal, unambiguous language and automatically compile them into learning objectives. $ω$-regular languages are a natural fit, given their role in formal verification and synthesis. However, most existing $ω$-regular RL approaches operate in an episodic, discounted setting with periodic resets, which is misaligned with $ω$-regular semantics over infinite traces. For continuing tasks, where the agent interacts with the environment over a single uninterrupted lifetime, the average-reward criterion is more appropriate. We focus on absolute liveness specifications, a subclass of $ω$-regular languages that cannot be violated by any finite prefix and thus aligns naturally with continuing interaction. We present the first model-free RL framework that translates absolute liveness specifications into average-reward objectives and enables learning in unknown communicating Markov decision processes (MDPs) without episodic resetting. We also introduce a reward structure for lexicographic multi-objective optimization: among policies that maximize the satisfaction probability of an absolute liveness specification, the agent maximizes an external average-reward objective. Our method guarantees convergence in unknown communicating MDPs and supports on-the-fly reductions that do not require full environment knowledge, enabling model-free learning. Experiments across several benchmarks show that the continuing, average-reward approach outperforms competing discount-based methods.
[628] HouseTS: A Large-Scale, Multimodal Spatiotemporal U.S. Housing Dataset and Benchmark
Shengkun Wang, Yanshen Sun, Fanglan Chen, Linhan Wang, Naren Ramakrishnan, Chang-Tien Lu, Yinlin Chen
Main category: cs.AI
TL;DR: HouseTS: A multimodal spatiotemporal dataset for ZIP-code-level housing market analysis with monthly indicators, POI dynamics, census variables, and annual aerial imagery, plus benchmarks for forecasting models and image-derived change annotations.
Details
Motivation: Existing housing datasets are fragmented with limited spatial coverage, temporal depth, or multimodal alignment. There's a need for comprehensive benchmarks to evaluate modern forecasting models and leverage aerial imagery in a time-aware, interpretable manner for housing market analysis.Method: Created HouseTS dataset covering monthly signals from 2012-2023 across 6,000+ ZIP codes in 30 major US metro areas. Aligns housing indicators, POI dynamics, census variables, and time-stamped aerial imagery. Benchmarked 16 model families and used vision-language pipeline with LLM-as-judge for image-derived textual change annotations.
Result: Provides a comprehensive multimodal dataset with standardized forecasting tasks, model benchmarks, and scalable interpretability tools. Dataset available on Kaggle with code on GitHub.
Conclusion: HouseTS bridges gaps in housing data resources by providing aligned multimodal time-series data, standardized benchmarks, and interpretability tools, enabling better evaluation of forecasting models and time-aware analysis of aerial imagery.
Abstract: Accurate long-horizon house-price forecasting requires benchmarks that capture temporal dynamics together with time-varying local context. However, existing public resources remain fragmented: many datasets have limited spatial coverage, temporal depth, or multimodal alignment; the robustness of modern deep forecasters and time-series foundation models on housing data is not well characterized; and aerial imagery is rarely leveraged in a time-aware and interpretable manner at scale. To bridge these gaps, we present HouseTS (House Time Series), a multimodal spatiotemporal dataset for ZIP-code-level housing-market analysis, covering monthly signals from March 2012 to December 2023 across over 6,000 ZIP codes in 30 major U.S. metropolitan areas. HouseTS aligns monthly housing-market indicators, monthly POI dynamics, and annual census-based socioeconomic variables under a unified schema, and includes time-stamped annual aerial imagery. Building on HouseTS, we define standardized long-horizon forecasting tasks for univariate and multivariate prediction and benchmark 16 model families spanning statistical methods, classical machine learning, deep neural networks, and time-series foundation models in both zero-shot and fine-tuned modes. We also provide image-derived textual change annotations from multi-year aerial image sequences via a vision–language pipeline with LLM-as-judge and human verification to support scalable interpretability analyses. HouseTS is available on Kaggle, with code and documentation on GitHub.
[629] Guideline Forest: Retrieval-Augmented Reasoning with Branching Experience-Induced Guidelines
Jiaxiang Chen, Zhuo Wang, Mingxi Zou, Qifan Wang, Zenglin Xu
Main category: cs.AI
TL;DR: Guideline Forest is a retrieval-augmented reasoning framework that stores and reuses high-quality reasoning traces as structured guidelines to improve multi-step reasoning in LLMs.
Details
Motivation: Existing RAG methods for reasoning either use online exploration during inference or heuristic supervision, but fail to effectively accumulate and reuse past reasoning experience to guide future reasoning processes.Method: The framework stores label-consistent reasoning traces as reusable memory, retrieves relevant experiences for new problems, and induces them into structured guidelines that steer reasoning with controlled branching and aggregation.
Result: Experiments on mathematical (GSM8K, MATH-500) and programming (MBPP, HumanEval) benchmarks show consistent improvements over strong reasoning baselines including CoT, ReAct, ToT, FoT, and AFlow.
Conclusion: Guideline Forest demonstrates that experience retrieval, guideline-induced diversity, and stepwise aggregation are key to effective reasoning, and the framework generalizes to diverse reasoning paradigms and supports multi-model collaboration.
Abstract: Retrieval-augmented generation (RAG) has been widely adopted to ground large language models (LLMs) in external knowledge, yet it remains largely underexplored for improving reasoning. Existing methods either rely on online exploration during inference or heuristic supervision over reasoning trajectories, but they fail to effectively accumulate and reuse past reasoning experience. We propose Guideline Forest, a retrieval-augmented reasoning framework that explicitly leverages experience to guide multi-step reasoning. The framework stores high-quality, label-consistent reasoning traces as reusable memory, retrieves relevant experiences for new problems, and induces them into structured guidelines that steer reasoning and enable controlled branching and aggregation. Experiments on mathematical (GSM8K, MATH-500) and programming (MBPP, HumanEval) benchmarks demonstrate consistent improvements over strong reasoning baselines, including CoT, ReAct, ToT, FoT, and AFlow. Further analyses show that experience retrieval, guideline-induced diversity, and stepwise aggregation are key to the framework’s effectiveness. Beyond single-model reasoning, Guideline Forest generalizes to enhance diverse reasoning paradigms and supports multi-model collaboration, highlighting its flexibility and scalability.
[630] Token-Level LLM Collaboration via FusionRoute
Nuoya Xiong, Yuhang Zhou, Hanqing Zeng, Zhaorun Chen, Furong Huang, Shuchao Bi, Lizhu Zhang, Zhuokai Zhao
Main category: cs.AI
TL;DR: FusionRoute is a token-level multi-LLM collaboration framework that uses a lightweight router to select experts at each decoding step while also contributing complementary logits to refine expert outputs, overcoming limitations of pure expert-only routing.
Details
Motivation: Address the dilemma between large general-purpose LLMs (expensive to train/deploy) and smaller domain-specialized models (efficient but poor generalization). Existing token-level collaboration methods relying solely on fixed expert outputs are fundamentally limited.Method: Proposes FusionRoute with a lightweight router that simultaneously: 1) selects the most suitable expert at each decoding step, and 2) contributes complementary logits via logit addition to refine or correct the selected expert’s next-token distribution. Theoretically shows pure expert-only routing is limited and expands policy class with trainable complementary generator.
Result: Outperforms both sequence- and token-level collaboration, model merging, and direct fine-tuning across Llama-3 and Gemma-2 families on diverse benchmarks (mathematical reasoning, code generation, instruction following). Remains competitive with domain experts on their respective tasks.
Conclusion: FusionRoute provides an effective framework for multi-LLM collaboration that balances efficiency and generalization, overcoming fundamental limitations of pure expert-only routing through complementary logit contributions.
Abstract: Large language models (LLMs) exhibit strengths across diverse domains. However, achieving strong performance across these domains with a single general-purpose model typically requires scaling to sizes that are prohibitively expensive to train and deploy. On the other hand, while smaller domain-specialized models are much more efficient, they struggle to generalize beyond their training distributions. To address this dilemma, we propose FusionRoute, a robust and effective token-level multi-LLM collaboration framework in which a lightweight router simultaneously (i) selects the most suitable expert at each decoding step and (ii) contributes a complementary logit that refines or corrects the selected expert’s next-token distribution via logit addition. Unlike existing token-level collaboration methods that rely solely on fixed expert outputs, we provide a theoretical analysis showing that pure expert-only routing is fundamentally limited: unless strong global coverage assumptions hold, it cannot in general realize the optimal decoding policy. By augmenting expert selection with a trainable complementary generator, FusionRoute expands the effective policy class and enables recovery of optimal value functions under mild conditions. Empirically, across both Llama-3 and Gemma-2 families and diverse benchmarks spanning mathematical reasoning, code generation, and instruction following, FusionRoute outperforms both sequence- and token-level collaboration, model merging, and direct fine-tuning, while remaining competitive with domain experts on their respective tasks.
[631] On Reasoning Strength Planning in Large Reasoning Models
Leheng Sheng, An Zhang, Zijian Wu, Weixiang Zhao, Changshuo Shen, Yi Zhang, Xiang Wang, Tat-Seng Chua
Main category: cs.AI
TL;DR: LRMs pre-plan reasoning strength via directional vectors in activations, enabling difficulty-aware token allocation and controllable reasoning length.
Details
Motivation: While large reasoning models automatically allocate more reasoning tokens for harder problems, the underlying mechanism for this difficulty-awareness remains unexplored. The paper aims to explain this phenomenon from the perspective of model activations.Method: The authors analyze model activations to show that LRMs pre-plan reasoning strengths before generation. They use linear probes to predict reasoning token numbers from question activations, identify a pre-allocated directional vector that controls reasoning strength, and demonstrate causal manipulation by adding/subtracting this vector.
Result: LRMs encode reasoning strength through a directional vector whose magnitude modulates reasoning token count. Manipulating this vector affects reasoning length and performance - subtracting reduces tokens/performance, while adding increases tokens and can improve performance. The vector consistently predicts reasoning length and modifies the token logits.
Conclusion: The work reveals internal mechanisms of reasoning in LRMs, showing they pre-plan reasoning strength via directional vectors. This enables applications like overthinking detection and efficient reasoning on simple problems, providing tools for controlling reasoning behaviors.
Abstract: Recent studies empirically reveal that large reasoning models (LRMs) can automatically allocate more reasoning strengths (i.e., the number of reasoning tokens) for harder problems, exhibiting difficulty-awareness for better task performance. While this automatic reasoning strength allocation phenomenon has been widely observed, its underlying mechanism remains largely unexplored. To this end, we provide explanations for this phenomenon from the perspective of model activations. We find evidence that LRMs pre-plan the reasoning strengths in their activations even before generation, with this reasoning strength causally controlled by the magnitude of a pre-allocated directional vector. Specifically, we show that the number of reasoning tokens is predictable solely based on the question activations using linear probes, indicating that LRMs estimate the required reasoning strength in advance. We then uncover that LRMs encode this reasoning strength through a pre-allocated directional vector embedded in the activations of the model, where the vector’s magnitude modulates the reasoning strength. Subtracting this vector can lead to reduced reasoning token number and performance, while adding this vector can lead to increased reasoning token number and even improved performance. We further reveal that this direction vector consistently yields positive reasoning length prediction, and it modifies the logits of end-of-reasoning token to affect the reasoning length. Finally, we demonstrate two potential applications of our findings: overthinking behavior detection and enabling efficient reasoning on simple problems. Our work provides new insights into the internal mechanisms of reasoning in LRMs and offers practical tools for controlling their reasoning behaviors. Our code is available at https://github.com/AlphaLab-USTC/LRM-plans-CoT.
[632] CID-GraphRAG: Enhancing Multi-Turn Dialogue Systems through Dual-Pathway Retrieval of Conversation Flow and Context Semantics
Ziqi Zhu, Tao Hu, Honglong Zhang, Dan Yang, Hangeng Chen, Mengran Zhang, Xilun Chen
Main category: cs.AI
TL;DR: CID-GraphRAG is a novel framework that improves multi-turn dialogue systems by combining intent transition graphs with semantic retrieval for better contextual coherence and goal-oriented progression in customer service conversations.
Details
Motivation: Existing dialogue systems struggle to maintain both contextual coherence and goal-oriented progression in multi-turn customer service conversations. Traditional RAG systems rely solely on semantic similarity or static knowledge graphs, which fail to capture conversational intent flow patterns.Method: Constructs intent transition graphs from historical goal-achieved dialogues and implements a dual-retrieval mechanism that balances intent-based graph traversal with semantic search, enabling simultaneous leverage of both conversational intent flow patterns and contextual semantics.
Result: Significantly outperforms both semantic-based and intent-based baselines across automatic metrics, LLM-as-a-Judge evaluations and human evaluations, with relative gains of 11.4% in BLEU, 4.9% in ROUGE, and 5.9% in METEOR, plus 57.9% improvement in response quality according to LLM-as-a-Judge evaluations.
Conclusion: Integrating intent transition structures with semantic retrieval creates a synergistic effect that neither approach achieves independently, establishing CID-GraphRAG as an effective framework for real-world multi-turn dialogue systems in customer service and other knowledge-intensive domains.
Abstract: We present CID-GraphRAG (Conversational Intent-Driven Graph Retrieval-Augmented Generation), a novel framework that addresses the limitations of existing dialogue systems in maintaining both contextual coherence and goal-oriented progression in multi-turn customer service conversations. Unlike traditional RAG systems that rely solely on semantic similarity or static knowledge graphs, CID-GraphRAG constructs intent transition graphs from goal-achieved historical dialogues and implements a dual-retrieval mechanism that balances intent-based graph traversal with semantic search. This approach enables the system to simultaneously leverage both conversational intent flow patterns and contextual semantics, significantly improving retrieval quality and response quality. In extensive experiments on real-world customer service dialogues, we demonstrated that CID-GraphRAG significantly outperforms both semantic-based and intent-based baselines across automatic metrics, LLM-as-a-Judge evaluations and human evaluations, with relative gains of 11.4% in BLEU, 4.9% in ROUGE, and 5.9% in METEOR. Most notably, CID-GraphRAG achieves a 57.9% improvement in response quality according to LLM-as-a-Judge evaluations. These results demonstrate that integrating intent transition structures with semantic retrieval creates a synergistic effect that neither approach achieves independently, establishing CID-GraphRAG as an effective framework for real-world multi-turn dialogue systems in customer service and other knowledge-intensive domains.
[633] Stability as a Liability:Systematic Breakdown of Linguistic Structure in LLMs
Xianzhe Meng, Qiangsheng Zeng, Ling Luo, Qinghan Yang, Jiarui Hao, Wenbo Wu, Qinyu Wang, Rui Yin, Lin Qi, Renzhi Lu
Main category: cs.AI
TL;DR: Training stability in LLMs can lead to low-entropy, repetitive generation despite smooth loss convergence, showing stability alone doesn’t guarantee generative quality.
Details
Motivation: The paper investigates how training stability affects the generation distribution in large language models, challenging the assumption that stable training dynamics necessarily lead to high-quality generative outputs.Method: Theoretical analysis of maximum likelihood training showing stable parameter trajectories lead to forward KL minimization with implicit entropy reduction, plus empirical validation using a controlled feedback-based training framework that stabilizes internal generation statistics.
Result: Stable training leads to models that concentrate probability mass on limited subsets of empirical modes, producing low-entropy, repetitive outputs across architectures and random seeds despite smooth loss convergence.
Conclusion: Optimization stability and generative expressivity are not inherently aligned, and stability alone is insufficient as an indicator of generative quality in language models.
Abstract: Training stability is typically regarded as a prerequisite for reliable optimization in large language models. In this work, we analyze how stabilizing training dynamics affects the induced generation distribution. We show that under standard maximum likelihood training, stable parameter trajectories lead stationary solutions to approximately minimize the forward KL divergence to the empirical distribution, while implicitly reducing generative entropy. As a consequence, the learned model can concentrate probability mass on a limited subset of empirical modes, exhibiting systematic degeneration despite smooth loss convergence. We empirically validate this effect using a controlled feedback-based training framework that stabilizes internal generation statistics, observing consistent low-entropy outputs and repetitive behavior across architectures and random seeds. It indicates that optimization stability and generative expressivity are not inherently aligned, and that stability alone is an insufficient indicator of generative quality.
[634] Lyria: A Genetic Algorithm-Driven Neuro-Symbolic Reasoning Framework for LLMs
Weizhi Tang, Kwabena Nuamah, Vaishak Belle
Main category: cs.AI
TL;DR: Lyria is a neuro-symbolic reasoning framework combining LLMs, genetic algorithms, and symbolic systems to address LLMs’ local optima and limited solution space coverage issues, with LAFT extension for fine-tuning weaker models.
Details
Motivation: LLMs struggle with two major issues: getting trapped in local optima and lacking exhaustive coverage of the solution space. The paper aims to investigate and improve these limitations through a neuro-symbolic approach.Method: Proposes Lyria, a neuro-symbolic reasoning framework integrating LLMs, genetic algorithms, and symbolic systems with 7 essential components. Also introduces LAFT for fine-tuning weaker models to imitate stronger models reasoning under Lyria framework.
Result: Extensive experiments with 4 LLMs across 3 problem types demonstrate Lyria’s efficacy. 7 ablation experiments systematically analyze performance factors. LAFT shows significant effectiveness against 9 baselines.
Conclusion: Lyria effectively addresses LLMs’ reasoning limitations through neuro-symbolic integration. LAFT enables knowledge transfer from stronger to weaker models. The paper reveals limitations and provides future research directions.
Abstract: While LLMs have demonstrated impressive abilities across various domains, they struggle with two major issues. The first is that LLMs trap themselves into local optima and the second is that they lack exhaustive coverage of the solution space. To investigate and improve these two issues, we propose Lyria, a neuro-symbolic reasoning framework building on the integration of LLMs, genetic algorithms, and symbolic systems, comprising 7 essential components. Through conducting extensive experiments with 4 LLMs across 3 types of problems, we demonstrated the efficacy of Lyria. Furthermore, with 7 additional ablation experiments, we further systematically analyzed and elucidated the factors that affect its performance. In addition, based on Lyria, we extend the ideas to the fine-tuning process of LLMs and introduce LAFT which enables a weaker model to imitate the reasoning process of a stronger model that reason under the Lyria reasoning framework. We demonstrate that the significant effectiveness of LAFT by conducting extensive experiments against 9 constructed baselines. We finally reveal the limitations and provide insights into future directions.
[635] Giving AI Agents Access to Cryptocurrency and Smart Contracts Creates New Vectors of AI Harm
Bill Marino, Ari Juels
Main category: cs.AI
TL;DR: Position paper arguing that giving AI agents access to cryptocurrencies and smart contracts could create new vectors of AI harm, proposing a taxonomy of these risks and calling for technical research to mitigate them.
Details
Motivation: Growing interest in giving AI agents access to cryptocurrencies and smart contracts raises concerns about potential new forms of AI harm that need to be systematically examined and addressed.Method: 1. Examines unique properties of cryptocurrencies and smart contracts that enable new AI harm vectors. 2. Develops a first-of-its-kind taxonomy of these new AI harm vectors. 3. Provides detailed descriptions of each identified harm vector.
Result: Identifies and categorizes novel AI harm vectors specific to cryptocurrency and smart contract contexts, establishing a foundational taxonomy for understanding these emerging risks.
Conclusion: Calls for more technical research to prevent and mitigate these new AI harm vectors, making it safer to endow AI agents with cryptocurrencies and smart contracts.
Abstract: There is growing interest in giving AI agents access to cryptocurrencies as well as to the smart contracts that transact them. But doing so, this position paper argues, could lead to formidable new vectors of AI harm. To support this argument, we first examine the unique properties of cryptocurrencies and smart contracts that could give rise to these new vectors of AI harm. Next, we describe each of these new vectors of AI harm in detail, providing a first-of-its-kind taxonomy. Finally, we conclude with a call for more technical research aimed at preventing and mitigating these new vectors of AI , thereby making it safer to endow AI agents with cryptocurrencies and smart contracts.
[636] Prospect Theory Fails for LLMs: Revealing Instability of Decision-Making under Epistemic Uncertainty
Rui Wang, Qihan Lin, Jiayu Liu, Qing Zong, Tianshi Zheng, Weiqi Wang, Yangqiu Song
Main category: cs.AI
TL;DR: This paper investigates whether Prospect Theory applies to Large Language Models and examines how epistemic markers (uncertainty expressions like “maybe”) affect LLM decision-making behavior through economic questionnaire experiments.
Details
Motivation: The paper aims to address two research gaps: 1) whether Prospect Theory (which models human decision-making under uncertainty) applies to contemporary LLMs, and 2) whether epistemic markers (linguistic expressions of uncertainty like "maybe") affect LLMs' decision-making behavior.Method: The authors design a three-stage experiment based on economic questionnaires. They propose a general evaluation framework to model LLMs’ decision-making under Prospect Theory, introducing uncertainty through empirical probability values associated with epistemic markers. They then incorporate these markers into the framework to examine their influence on LLM decision-making.
Result: The findings suggest that modeling LLMs’ decision-making with Prospect Theory is not consistently reliable, particularly when uncertainty is expressed in diverse linguistic forms through epistemic markers.
Conclusion: Prospect Theory may not be a reliable framework for modeling LLM decision-making, especially when uncertainty is expressed linguistically through epistemic markers, highlighting limitations in applying human decision-making theories to LLMs.
Abstract: Prospect Theory (PT) models human decision-making under uncertainty, while epistemic markers (e.g., maybe) serve to express uncertainty in language. However, it remains largely unexplored whether Prospect Theory applies to contemporary Large Language Models and whether epistemic markers, which express human uncertainty, affect their decision-making behaviour. To address these research gaps, we design a three-stage experiment based on economic questionnaires. We propose a more general and precise evaluation framework to model LLMs’ decision-making behaviour under PT, introducing uncertainty through the empirical probability values associated with commonly used epistemic markers in comparable contexts. We then incorporate epistemic markers into the evaluation framework based on their corresponding probability values to examine their influence on LLM decision-making behaviours. Our findings suggest that modelling LLMs’ decision-making with PT is not consistently reliable, particularly when uncertainty is expressed in diverse linguistic forms. Our code is released in https://github.com/HKUST-KnowComp/MarPT.
[637] AOrchestra: Automating Sub-Agent Creation for Agentic Orchestration
Jianhao Ruan, Zhihao Xu, Yiran Peng, Fashen Ren, Zhaoyang Yu, Xinbing Liang, Jinyu Xiang, Yongru Chen, Bang Liu, Chenglin Wu, Yuyu Luo, Jiayi Zhang
Main category: cs.AI
TL;DR: AOrchestra introduces a unified agent abstraction framework for dynamic multi-agent task solving with on-demand agent creation and orchestration.
Details
Motivation: Current language agent systems lack dynamic abstraction views of sub-agents, hurting adaptability for complex, long-horizon tasks. Existing designs don't provide framework-agnostic approaches for orchestrating diverse agents as tools.Method: Proposes a unified agent abstraction: (Instruction, Context, Tools, Model) tuple that serves as a compositional recipe. A central orchestrator concretizes this tuple at each step: curates context, selects tools/models, and delegates execution via automatic agent creation.
Result: Achieves 16.28% relative improvement against strongest baselines on GAIA, SWE-Bench, and Terminal-Bench when paired with Gemini-3-Flash. Enables controllable performance-cost trade-off approaching Pareto efficiency.
Conclusion: AOrchestra provides a framework-agnostic approach for dynamic agent orchestration that reduces human engineering effort while improving adaptability and performance for complex tasks.
Abstract: Language agents have shown strong promise for task automation. Realizing this promise for increasingly complex, long-horizon tasks has driven the rise of a sub-agent-as-tools paradigm for multi-turn task solving. However, existing designs still lack a dynamic abstraction view of sub-agents, thereby hurting adaptability. We address this challenge with a unified, framework-agnostic agent abstraction that models any agent as a tuple Instruction, Context, Tools, Model. This tuple acts as a compositional recipe for capabilities, enabling the system to spawn specialized executors for each task on demand. Building on this abstraction, we introduce an agentic system AOrchestra, where the central orchestrator concretizes the tuple at each step: it curates task-relevant context, selects tools and models, and delegates execution via on-the-fly automatic agent creation. Such designs enable reducing human engineering efforts, and remain framework-agnostic with plug-and-play support for diverse agents as task executors. It also enables a controllable performance-cost trade-off, allowing the system to approach Pareto-efficient. Across three challenging benchmarks (GAIA, SWE-Bench, Terminal-Bench), AOrchestra achieves 16.28% relative improvement against the strongest baseline when paired with Gemini-3-Flash. The code is available at: https://github.com/FoundationAgents/AOrchestra
[638] HiFo-Prompt: Prompting with Hindsight and Foresight for LLM-based Automatic Heuristic Design
Chentong Chen, Mengyuan Zhong, Ye Fan, Jialong Shi, Jianyong Sun
Main category: cs.AI
TL;DR: HiFo-Prompt is a framework that uses LLMs with foresight and hindsight prompting strategies to design evolutionary computation heuristics, enabling adaptive search and knowledge accumulation from past successes.
Details
Motivation: Current LLM-based Automatic Heuristic Design (AHD) in Evolutionary Computation suffers from static operators and lacks knowledge accumulation mechanisms, limiting effectiveness and requiring excessive LLM queries.Method: Uses two synergistic prompting strategies: Foresight prompts adaptively steer search based on population dynamics, while Hindsight prompts distill successful heuristics from past generations into reusable design principles, creating a persistent knowledge base.
Result: Significantly outperforms state-of-the-art LLM-based AHD methods, generating higher-quality heuristics with faster convergence and superior query efficiency.
Conclusion: HiFo-Prompt effectively transforms transient discoveries into persistent knowledge, enabling LLMs to learn from experience and improve heuristic design in evolutionary computation.
Abstract: LLM-based Automatic Heuristic Design (AHD) within Evolutionary Computation (EC) frameworks has shown promising results. However, its effectiveness is hindered by the use of static operators and the lack of knowledge accumulation mechanisms. We introduce HiFo-Prompt, a framework that guides LLMs with two synergistic prompting strategies: Foresight and Hindsight. Foresight-based prompts adaptively steer the search based on population dynamics, managing the exploration-exploitation trade-off. In addition, hindsight-based prompts mimic human expertise by distilling successful heuristics from past generations into fundamental, reusable design principles. This dual mechanism transforms transient discoveries into a persistent knowledge base, enabling the LLM to learn from its own experience. Empirical results demonstrate that HiFo-Prompt significantly outperforms state-of-the-art LLM-based AHD methods, generating higher-quality heuristics while achieving substantially faster convergence and superior query efficiency. Our code is available at https://github.com/Challenger-XJTU/HiFo-Prompt.
[639] Coarse-to-Fine Grounded Memory for LLM Agent Planning
Wei Yang, Jinwei Xiao, Hongming Zhang, Qingyang Zhang, Yanna Wang, Bo Xu
Main category: cs.AI
TL;DR: Coarse-to-Fine Grounded Memory framework that uses LLMs to ground environmental information at multiple granularities for improved planning in complex tasks.
Details
Motivation: Existing LLM-based agents for planning tasks rely on single-granularity memory from environmental interactions, which limits knowledge diversity and planning flexibility due to constrained experience quality.Method: Proposes a framework that grounds environmental information into coarse-grained focus points to guide experience collection, then grounds actionable hybrid-grained tips from each experience. At inference, retrieves task-relevant experiences and tips for planning, and when facing anomalies, grounds current situation into fine-grained key information for self-QA reflection and plan correction.
Result: Not specified in the abstract, but the framework aims to improve planning flexibility and adaptation to diverse scenarios by leveraging multi-granularity grounded memories.
Conclusion: The proposed framework enables LLM-based agents to better leverage environmental information through coarse-to-fine memory grounding, enhancing planning capabilities in complex tasks.
Abstract: Recent advancements in Large Language Models (LLMs) have driven growing interest in LLM-based agents for complex planning tasks. To avoid costly agent training, many studies adopted memory mechanism that enhances LLM with offline experiences or online trajectory analysis. However, existing works focus on single-granularity memory derived from dynamic environmental interactions, which are inherently constrained by the quality of the collected experiences. This limitation, in turn, constrain the diversity of knowledge and the flexibility of planning. We propose Coarse-to-Fine Grounded Memory (\Ours{}), a novel framework that grounds coarse-to-fine memories with LLM, thereby fully leverage them for flexible adaptation to diverse scenarios. \Ours{} grounds environmental information into coarse-grained focus points to guide experience collection in training tasks, followed by grounding of actionable hybrid-grained tips from each experience. At inference, \Ours{} retrieves task-relevant experiences and tips to support planning. When facing environmental anomalies, the LLM grounds the current situation into fine-grained key information, enabling flexible self-QA reflection and plan correction.
[640] Steerable Adversarial Scenario Generation through Test-Time Preference Alignment
Tong Nie, Yuewen Mei, Yihong Tang, Junlin He, Jie Sun, Haotian Shi, Wei Ma, Jian Sun
Main category: cs.AI
TL;DR: SAGE introduces a steerable adversarial scenario generation framework for autonomous driving that enables fine-grained control over the trade-off between adversariality and realism at inference time without retraining.
Details
Motivation: Existing adversarial scenario generation methods for autonomous driving safety assessment are constrained to fixed trade-offs between adversariality and realism, lacking flexibility for diverse training/testing needs and requiring retraining for different preferences.Method: Reframes scenario generation as multi-objective preference alignment; proposes hierarchical group-based preference optimization to decouple hard constraints from soft preferences; fine-tunes two experts on opposing preferences and constructs continuous policy spectrum via linear weight interpolation at inference time.
Result: SAGE generates scenarios with superior balance of adversariality and realism, enables more effective closed-loop training of driving policies, and provides theoretical justification through linear mode connectivity.
Conclusion: SAGE offers a flexible, efficient framework for steerable adversarial scenario generation that can adapt to diverse safety assessment requirements without retraining.
Abstract: Adversarial scenario generation is a cost-effective approach for safety assessment of autonomous driving systems. However, existing methods are often constrained to a single, fixed trade-off between competing objectives such as adversariality and realism. This yields behavior-specific models that cannot be steered at inference time, lacking the efficiency and flexibility to generate tailored scenarios for diverse training and testing requirements. In view of this, we reframe the task of adversarial scenario generation as a multi-objective preference alignment problem and introduce a new framework named \textbf{S}teerable \textbf{A}dversarial scenario \textbf{GE}nerator (SAGE). SAGE enables fine-grained test-time control over the trade-off between adversariality and realism without any retraining. We first propose hierarchical group-based preference optimization, a data-efficient offline alignment method that learns to balance competing objectives by decoupling hard feasibility constraints from soft preferences. Instead of training a fixed model, SAGE fine-tunes two experts on opposing preferences and constructs a continuous spectrum of policies at inference time by linearly interpolating their weights. We provide theoretical justification for this framework through the lens of linear mode connectivity. Extensive experiments demonstrate that SAGE not only generates scenarios with a superior balance of adversariality and realism but also enables more effective closed-loop training of driving policies. Project page: https://tongnie.github.io/SAGE/.
[641] Generative Ontology: When Structured Knowledge Learns to Create
Benny Cheung
Main category: cs.AI
TL;DR: Generative Ontology framework combines LLM creativity with structural constraints from executable schemas for generating valid domain artifacts like tabletop games.
Details
Motivation: Traditional ontologies provide structural validity but lack creativity, while LLMs generate fluently but produce outputs lacking structural validity and hallucinate mechanisms. Need to synthesize complementary strengths of both approaches.Method: Generative Ontology encodes domain knowledge as executable Pydantic schemas that constrain LLM generation via DSPy signatures. Uses multi-agent pipeline with specialized roles (Mechanics Architect, Theme Weaver, Balance Critic) each with professional “anxiety” to prevent shallow outputs. Incorporates retrieval-augmented generation from existing exemplars.
Result: Demonstrated through GameGrammar generating tabletop games. Multi-agent specialization produced largest quality gains (fun d=1.12, depth d=1.59; p<.001). Schema validation eliminated structural errors (d=4.78). Generated designs scored 7-8 vs published games 8-9 on fun scale. LLM-based evaluator showed good reliability (ICC 0.836-0.989).
Conclusion: Generative Ontology framework successfully combines structural validity from ontologies with LLM creativity. Pattern generalizes to any domain with expert vocabulary, validity constraints, and accumulated exemplars.
Abstract: Traditional ontologies describe domain structure but cannot generate novel artifacts. Large language models generate fluently but produce outputs lacking structural validity, hallucinating mechanisms without components, goals without end conditions. We introduce Generative Ontology, a framework synthesizing these complementary strengths: ontology provides the grammar; the LLM provides the creativity. Generative Ontology encodes domain knowledge as executable Pydantic schemas constraining LLM generation via DSPy signatures. A multi-agent pipeline assigns specialized roles: a Mechanics Architect designs game systems, a Theme Weaver integrates narrative, a Balance Critic identifies exploits, each carrying a professional “anxiety” that prevents shallow outputs. Retrieval-augmented generation grounds designs in precedents from existing exemplars. We demonstrate the framework through GameGrammar, generating complete tabletop game designs, and present three empirical studies. An ablation study (120 designs, 4 conditions) shows multi-agent specialization produces the largest quality gains (fun d=1.12, depth d=1.59; p<.001), while schema validation eliminates structural errors (d=4.78). A benchmark against 20 published board games reveals structural parity but a bounded creative gap (fun d=1.86): generated designs score 7-8 while published games score 8-9. A test-retest study (50 evaluations) validates the LLM-based evaluator, with 7/9 metrics achieving Good-to-Excellent reliability (ICC 0.836-0.989). The pattern generalizes beyond games. Any domain with expert vocabulary, validity constraints, and accumulated exemplars is a candidate for Generative Ontology.
[642] Rethinking Explainable Disease Prediction: Synergizing Accuracy and Reliability via Reflective Cognitive Architecture
Zijian Shao, Haiyang Shen, Mugeng Liu, Gecheng Fu, Yaoqi Guo, Yanfeng Wang, Yun Ma
Main category: cs.AI
TL;DR: RCA framework enables LLMs to learn from tabular data through experience and reflection, achieving both high predictive accuracy and interpretable explanations in medical applications.
Details
Motivation: Addresses the persistent trade-off in clinical decision-making where accurate models are opaque "black boxes" while interpretable methods lack predictive precision or statistical grounding.Method: Proposes Reflective Cognitive Architecture (RCA) with two core mechanisms: iterative rules optimization that refines logical argumentation from prediction errors, and distribution-aware rules check that grounds logic in global statistical evidence.
Result: RCA achieves state-of-the-art predictive performance and superior robustness to data noise across diverse medical datasets, including a proprietary CRT cohort and two large-scale datasets, while generating clear, logical, evidence-based explanations.
Conclusion: High predictive accuracy and high-quality descriptive explanations are synergistic outcomes achievable through deep understanding of data, demonstrated by RCA’s effectiveness in clinical decision-making even at scale.
Abstract: In clinical decision-making, predictive models face a persistent trade-off: accurate models are often opaque “black boxes,” while interpretable methods frequently lack predictive precision or statistical grounding. In this paper, we challenge this dichotomy, positing that high predictive accuracy and high-quality descriptive explanations are not competing goals but synergistic outcomes of a deep, first-hand understanding of data. We propose the Reflective Cognitive Architecture (RCA), a novel framework designed to enable Large Language Models (LLMs) to learn directly from tabular data through experience and reflection. RCA integrates two core mechanisms: an iterative rules optimization process that refines logical argumentation by learning from prediction errors, and a distribution-aware rules check that grounds this logic in global statistical evidence to ensure robustness. We evaluated RCA against over 20 baselines - ranging from traditional machine learning to advanced reasoning LLMs and agents - across diverse medical datasets, including a proprietary real-world Catheter-Related Thrombosis (CRT) cohort. Crucially, to demonstrate real-world scalability, we extended our evaluation to two large-scale datasets. The results confirm that RCA achieves state-of-the-art predictive performance and superior robustness to data noise while simultaneously generating clear, logical, and evidence-based explanatory statements, maintaining its efficacy even at scale. The code is available at https://github.com/ssssszj/RCA.
[643] Correct Reasoning Paths Visit Shared Decision Pivots
Dongkyu Cho, Amy B. Z. Zhang, Bilel Fehri, Sheng Wang, Rumi Chunara, Hengrui Cai, Rui Song
Main category: cs.AI
TL;DR: A self-training method that uses “decision pivots” - minimal verifiable checkpoints - to align LLM reasoning without ground truth reasoning data, improving performance on reasoning benchmarks.
Details
Motivation: Chain-of-thought reasoning shows LLM thinking processes, but verifying these reasoning traces at scale remains unsolved. There's a need for methods to align and verify reasoning without ground truth reasoning data or external metrics.Method: Proposes decision pivots - minimal verifiable checkpoints that correct reasoning must visit. Uses a self-training pipeline: (1) samples diverse reasoning paths and mines shared decision pivots, (2) compresses traces into pivot-focused short-path reasoning using an auxiliary verifier, (3) post-trains the model using self-generated outputs.
Result: Experiments on standard benchmarks (LogiQA, MedQA, MATH500) show the method’s effectiveness in improving reasoning performance without ground truth reasoning data.
Conclusion: The decision pivot approach enables scalable verification and alignment of LLM reasoning by focusing on essential checkpoints that correct reasoning must satisfy, providing a practical solution for reasoning verification.
Abstract: Chain-of-thought (CoT) reasoning exposes the intermediate thinking process of large language models (LLMs), yet verifying those traces at scale remains unsolved. In response, we introduce the idea of decision pivots-minimal, verifiable checkpoints that any correct reasoning path must visit. We hypothesize that correct reasoning, though stylistically diverse, converge on the same pivot set, while incorrect ones violate at least one pivot. Leveraging this property, we propose a self-training pipeline that (i) samples diverse reasoning paths and mines shared decision pivots, (ii) compresses each trace into pivot-focused short-path reasoning using an auxiliary verifier, and (iii) post-trains the model using its self-generated outputs. The proposed method aligns reasoning without ground truth reasoning data or external metrics. Experiments on standard benchmarks such as LogiQA, MedQA, and MATH500 show the effectiveness of our method.
[644] Lifelong Learning with Behavior Consolidation for Vehicle Routing
Jiyuan Pei, Yi Mei, Jialin Liu, Mengjie Zhang, Xin Yao
Main category: cs.AI
TL;DR: A lifelong learning framework for neural VRP solvers that addresses catastrophic forgetting when learning sequential tasks with diverse distributions and scales.
Details
Motivation: Existing neural solvers for routing problems suffer from poor zero-shot generalization to new tasks or catastrophic forgetting when fine-tuned, lacking a lifelong learning approach for sequential tasks with diverse distributions and scales.Method: Proposes LLR-BC (Lifelong Learning Router with Behavior Consolidation) that aligns behaviors of solvers trained on new tasks with buffered ones in a decision-seeking way, assigning greater weights to decisions with lower confidence to focus on crucial experiences.
Result: Extensive experiments on capacitated vehicle routing problems and traveling salesman problems demonstrate LLR-BC’s effectiveness in training high-performance neural solvers, addressing catastrophic forgetting, maintaining plasticity, and improving zero-shot generalization.
Conclusion: LLR-BC provides an effective lifelong learning framework for neural VRP solvers that can handle sequential tasks with diverse distributions and scales while avoiding catastrophic forgetting.
Abstract: Recent neural solvers have demonstrated promising performance in learning to solve routing problems. However, existing studies are primarily based on one-off training on one or a set of predefined problem distributions and scales, i.e., tasks. When a new task arises, they typically rely on either zero-shot generalization, which may be poor due to the discrepancies between the new task and the training task(s), or fine-tuning the pretrained solver on the new task, which possibly leads to catastrophic forgetting of knowledge acquired from previous tasks. This paper explores a novel lifelong learning paradigm for neural VRP solvers, where multiple tasks with diverse distributions and scales arise sequentially over time. Solvers are required to effectively and efficiently learn to solve new tasks while maintaining their performance on previously learned tasks. Consequently, a novel framework called Lifelong Learning Router with Behavior Consolidation (LLR-BC) is proposed. LLR-BC consolidates prior knowledge effectively by aligning behaviors of the solver trained on a new task with the buffered ones in a decision-seeking way. To encourage more focus on crucial experiences, LLR-BC assigns greater consolidated weights to decisions with lower confidence. Extensive experiments on capacitated vehicle routing problems and traveling salesman problems demonstrate LLR-BC’s effectiveness in training high-performance neural solvers in a lifelong learning setting, addressing the catastrophic forgetting issue, maintaining their plasticity, and improving zero-shot generalization ability.
[645] TRACE: Learning to Compute on Circuit Graphs
Ziyang Zheng, Jiaying Zhu, Jingyi Zhou, Qiang Xu
Main category: cs.AI
TL;DR: TRACE introduces a hierarchical transformer architecture with function shift learning for modeling circuit functional behavior, outperforming existing graph neural networks on circuit analysis tasks.
Details
Motivation: Current graph neural networks (MPNNs and Transformers) are architecturally mismatched for modeling circuit computation because they assume permutation invariance, which fails to capture the position-aware, hierarchical nature of circuit functional behavior.Method: Two key innovations: 1) Hierarchical Transformer that mirrors step-by-step computation flow, replacing flawed permutation-invariant aggregation; 2) Function shift learning objective that decouples learning by predicting only the discrepancy between true global function and simple local approximation.
Result: TRACE substantially outperforms all prior architectures across comprehensive benchmarks on various circuit modalities including Register Transfer Level graphs, And-Inverter Graphs, and post-mapping netlists.
Conclusion: The architecturally-aligned backbone and decoupled learning objective form a more robust paradigm for learning functional behavior of circuit graphs, addressing fundamental limitations of existing graph representation learning approaches.
Abstract: Learning to compute, the ability to model the functional behavior of a circuit graph, is a fundamental challenge for graph representation learning. Yet, the dominant paradigm is architecturally mismatched for this task. This flawed assumption, central to mainstream message passing neural networks (MPNNs) and their conventional Transformer-based counterparts, prevents models from capturing the position-aware, hierarchical nature of computation. To resolve this, we introduce TRACE, a new paradigm built on an architecturally sound backbone and a principled learning objective. First, TRACE employs a Hierarchical Transformer that mirrors the step-by-step flow of computation, providing a faithful architectural backbone that replaces the flawed permutation-invariant aggregation. Second, we introduce function shift learning, a novel objective that decouples the learning problem. Instead of predicting the complex global function directly, our model is trained to predict only the function shift, the discrepancy between the true global function and a simple local approximation that assumes input independence. We validate this paradigm on various circuits modalities, including Register Transfer Level graphs, And-Inverter Graphs and post-mapping netlists. Across a comprehensive suite of benchmarks, TRACE substantially outperforms all prior architectures. These results demonstrate that our architecturally-aligned backbone and decoupled learning objective form a more robust paradigm for the fundamental challenge of learning the functional behavior of a circuit graph.
[646] Agentic AI Reasoning for Mobile Edge General Intelligence: Fundamentals, Approaches, and Directions
Mingyi Luo, Ruichen Zhang, Xiangwang Hou, Jun Du, Chunxiao Jiang, Yong Ren, Dusit Niyato, Shiwen Mao
Main category: cs.AI
TL;DR: A joint optimization framework for efficient LLM reasoning deployment in Mobile Edge General Intelligence (MEGI) that balances reasoning quality and resource efficiency through adaptive CoT prompting and distributed MoE architecture.
Details
Motivation: Deploying LLM-based agentic AI reasoning in MEGI environments faces challenges due to high computational demands of reasoning and limited edge device resources, requiring efficient optimization solutions.Method: Proposes a distributed framework combining reasoning enhancement via adaptive Chain-of-Thought (CoT) prompting with scalable deployment through distributed Mixture-of-Experts (MoE) architecture, modeling reasoning depth as a dynamic network resource variable optimized jointly with expert activation and transmission power.
Result: Experimental evaluations show the framework effectively balances reasoning quality and resource efficiency, achieving both accuracy and latency satisfaction rates of 90% with less than one second of additional inference time.
Conclusion: The proposed framework validates practical viability of deploying sophisticated LLM reasoning in resource-constrained MEGI systems through joint optimization of reasoning enhancement and distributed deployment.
Abstract: The rapid advancement of large language models (LLMs) has enabled an emergence of agentic artificial intelligence (AI) with powerful reasoning and autonomous decision-making capabilities. This integration with edge computing has led to the development of Mobile Edge General Intelligence (MEGI), which brings real-time, privacy-preserving reasoning to the network edge. However, deploying LLM-based agentic AI reasoning in MEGI environments poses significant challenges due to the high computational demands of reasoning and the limited resources of edge devices. To address these challenges, we propose a joint optimization framework for efficient LLM reasoning deployment in MEGI. First, we systematically review enhancement methods to identify mechanisms suitable for edge adaptation. Subsequently, we present a distributed framework that synergizes reasoning enhancement via adaptive CoT prompting with scalable deployment through a distributed MoE architecture. An important innovation of this approach involves modeling reasoning depth as a dynamic network resource variable, which is optimized jointly with expert activation and transmission power. This mechanism allows the system to dynamically regulate expert networks and reasoning complexity according to task requirements and device capabilities. Experimental evaluations in mobile edge environments demonstrate that the proposed framework effectively balances reasoning quality and resource efficiency. The results show that with less than one second of additional inference time, both accuracy and latency satisfaction rate can reach 90%, validating the practical viability of deploying sophisticated LLM reasoning in resource-constrained MEGI systems.
[647] AIReg-Bench: Benchmarking Language Models That Assess AI Regulation Compliance
Bill Marino, Rosco Hunter, Christoph Schnabl, Zubair Jamali, Marinos Emmanouil Kalpakos, Mudra Kashyap, Isaiah Hinton, Alexa Hanson, Maahum Nazir, Felix Steffek, Hongkai Wen, Nicholas D. Lane
Main category: cs.AI
TL;DR: AIReg-Bench: First benchmark dataset for evaluating LLMs’ ability to assess compliance with EU AI Act regulations.
Details
Motivation: With governments regulating AI and growing interest in using LLMs for AI regulation compliance assessment, there's currently no benchmark to evaluate LLM performance on this task.Method: Created dataset through two-step process: (1) LLM-generated 120 technical documentation excerpts of fictional AI systems, (2) legal experts reviewed and annotated each sample for AI Act violations.
Result: Provides benchmark dataset and evaluation code, establishes baseline for understanding LLM capabilities in AI regulation compliance assessment.
Conclusion: AIReg-Bench fills critical gap by providing first benchmark for evaluating LLMs on AI regulation compliance assessment, enabling comparison of subsequent models.
Abstract: As governments move to regulate AI, there is growing interest in using Large Language Models (LLMs) to assess whether or not an AI system complies with a given AI Regulation (AIR). However, there is presently no way to benchmark the performance of LLMs at this task. To fill this void, we introduce AIReg-Bench: the first open benchmark dataset designed to test how well LLMs can assess compliance with the EU AI Act (AIA). We created this dataset through a two-step process: (1) by prompting an LLM with carefully structured instructions, we generated 120 technical documentation excerpts (samples), each depicting a fictional, albeit plausible, AI system – of the kind an AI provider might produce to demonstrate their compliance with AIR; (2) legal experts then reviewed and annotated each sample to indicate whether, and in what way, the AI system described therein violates specific Articles of the AIA. The resulting dataset, together with our evaluation of whether frontier LLMs can reproduce the experts’ compliance labels, provides a starting point to understand the opportunities and limitations of LLM-based AIR compliance assessment tools and establishes a benchmark against which subsequent LLMs can be compared. The dataset and evaluation code are available at https://github.com/camlsys/aireg-bench.
[648] SurveyG: A Multi-Agent LLM Framework with Hierarchical Citation Graph for Automated Survey Generation
Minh-Anh Nguye, Minh-Duc Nguyen, Ha Lan N. T., Kieu Hai Dang, Nguyen Tien Dong, Dung D. Le
Main category: cs.AI
TL;DR: SurveyG is an LLM-based agent framework that uses hierarchical citation graphs to generate structured, comprehensive survey papers by capturing research evolution and semantic relationships between papers.
Details
Motivation: Existing LLM-based survey generation methods extract content from papers but overlook structural relationships, resulting in surveys lacking coherent taxonomy and deeper contextual understanding of research progress.Method: Proposes SurveyG framework with hierarchical citation graph (Foundation, Development, Frontier layers) that captures citation dependencies and semantic relatedness. Uses horizontal search within layers and vertical traversal across layers for multi-level summaries, consolidated into structured outline with multi-agent validation.
Result: Outperforms state-of-the-art frameworks in evaluations by human experts and LLM-as-a-judge, producing more comprehensive and better structured surveys aligned with field knowledge taxonomy.
Conclusion: SurveyG effectively addresses limitations of existing LLM-based survey generation by incorporating structural and contextual knowledge through hierarchical citation graphs, resulting in higher quality survey papers.
Abstract: Large language models (LLMs) are increasingly adopted for automating survey paper generation \cite{wang2406autosurvey, liang2025surveyx, yan2025surveyforge,su2025benchmarking,wen2025interactivesurvey}. Existing approaches typically extract content from a large collection of related papers and prompt LLMs to summarize them directly. However, such methods often overlook the structural relationships among papers, resulting in generated surveys that lack a coherent taxonomy and a deeper contextual understanding of research progress. To address these shortcomings, we propose \textbf{SurveyG}, an LLM-based agent framework that integrates \textit{hierarchical citation graph}, where nodes denote research papers and edges capture both citation dependencies and semantic relatedness between their contents, thereby embedding structural and contextual knowledge into the survey generation process. The graph is organized into three layers: \textbf{Foundation}, \textbf{Development}, and \textbf{Frontier}, to capture the evolution of research from seminal works to incremental advances and emerging directions. By combining horizontal search within layers and vertical depth traversal across layers, the agent produces multi-level summaries, which are consolidated into a structured survey outline. A multi-agent validation stage then ensures consistency, coverage, and factual accuracy in generating the final survey. Experiments, including evaluations by human experts and LLM-as-a-judge, demonstrate that SurveyG outperforms state-of-the-art frameworks, producing surveys that are more comprehensive and better structured to the underlying knowledge taxonomy of a field.
[649] The Achilles’ Heel of LLMs: How Altering a Handful of Neurons Can Cripple Language Abilities
Zixuan Qin, Qingchen Yu, Kunlin Lyu, Zhaoxin Fan, Yifan Sun
Main category: cs.AI
TL;DR: LLMs contain ultra-sparse critical neurons that cause catastrophic failure when disrupted, concentrated in outer layers’ MLP down_proj components, with sharp phase transitions in performance degradation.
Details
Motivation: Inspired by neuroscience findings that a small subset of biological neurons are crucial for core cognitive functions, the paper investigates whether LLMs similarly contain a small subset of critical neurons whose disruption causes catastrophic model failure.Method: Proposes Perturbation-based Causal Identification of Critical Neurons method to systematically locate critical neurons in LLMs through targeted perturbations, tested across diverse model architectures and scales.
Result: Three key findings: (1) LLMs contain ultra-sparse critical neuron sets whose disruption causes catastrophic collapse (72B-parameter model perplexity increases by up to 20 orders of magnitude); (2) Critical neurons concentrate in outer layers, particularly MLP down_proj components; (3) Performance degradation shows sharp phase transitions rather than gradual decline.
Conclusion: LLMs have critical neuron vulnerabilities similar to biological brains, with implications for model robustness, interpretability, and deployment security. Findings can guide more robust architectures and safety-critical applications.
Abstract: Large Language Models (LLMs) have become foundational tools in natural language processing, powering a wide range of applications and research. Many studies have shown that LLMs share significant similarities with the human brain. Recent neuroscience research has found that a small subset of biological neurons in the human brain are crucial for core cognitive functions, which raises a fundamental question: do LLMs also contain a small subset of critical neurons? In this paper, we investigate this question by proposing a Perturbation-based Causal Identification of Critical Neurons method to systematically locate such critical neurons in LLMs. Our findings reveal three key insights: (1) LLMs contain ultra-sparse critical neuron sets. Disrupting these critical neurons can cause a 72B-parameter model with over 1.1 billion neurons to completely collapse, with perplexity increasing by up to 20 orders of magnitude; (2) These critical neurons are not uniformly distributed, but tend to concentrate in the outer layers, particularly within the MLP down_proj components; (3) Performance degradation exhibits sharp phase transitions, rather than a gradual decline, when these critical neurons are disrupted. Through comprehensive experiments across diverse model architectures and scales, we provide deeper analysis of these phenomena and their implications for LLM robustness and interpretability. These findings can offer guidance for developing more robust model architectures and improving deployment security in safety-critical applications. Our code is available at https://github.com/qqqqqqqzx/The-Achilles-Heel-of-LLMs.
[650] OpenPhone: Mobile Agentic Foundation Models
Yangqin Jiang, Chao Huang
Main category: cs.AI
TL;DR: OpenPhone is a mobile GUI agent system that uses device-cloud collaboration to balance performance and efficiency, enhancing a small on-device model with specialized training and only escalating complex tasks to the cloud.
Details
Motivation: Mobile GUI agents face a dilemma: truly on-device models (4B or smaller) lack sufficient performance, while capable models (starting from 7B) are too large for mobile deployment or prohibitively costly as cloud-only solutions.Method: OpenPhone leverages device-cloud collaboration, enhancing Qwen2.5-VL-3B via two-stage SFT->GRPO training on synthetic GUI data, integrates efficient long-reasoning and memory management, and defaults to on-device execution while escalating challenging subtasks to the cloud via real-time complexity assessment.
Result: Experiments on the online AndroidLab benchmark and diverse apps show OpenPhone matches or nears larger models’ performance with significant reduction in cloud costs.
Conclusion: OpenPhone demonstrates that device-cloud collaboration can effectively balance performance and efficiency for mobile GUI agents, making capable multimodal agents practical for mobile platforms.
Abstract: With the advancement of multimodal large language models (MLLMs), building GUI agent systems has become an increasingly promising direction–especially for mobile platforms, given their rich app ecosystems and intuitive touch interactions. Yet mobile GUI agents face a critical dilemma: truly on-device models (4B or smaller) lack sufficient performance, while capable models (starting from 7B) are either too large for mobile deployment or prohibitively costly (e.g., cloud-only closed-source MLLMs). To resolve this, we propose OpenPhone, a mobile GUI agent system that leverages device-cloud collaboration to tap the cost-efficiency of on device models and the high capability of cloud models, while avoiding their drawbacks. Specifically, OpenPhone enhances Qwen2.5-VL-3B via two-stage SFT->GRPO training on synthetic GUI data for strong decision-making, integrates an efficient long-reasoning and memory management mechanism to utilize historical interactions under tight resources, and defaults to on-device execution–only escalating challenging subtasks to the cloud via real-time complexity assessment. Experiments on the online AndroidLab benchmark and diverse apps show OpenPhone matches or nears larger models, with a significant reduction in cloud costs.
[651] GUI Knowledge Bench: Revealing the Knowledge Gap of VLMs in GUI Tasks
Chenrui Shi, Zedong Yu, Zhi Gao, Ruining Feng, Enqi Liu, Yuwei Wu, Yunde Jia, Liuyu Xiang, Zhaofeng He, Qing Li
Main category: cs.AI
TL;DR: The paper introduces GUI Knowledge Bench, a benchmark for evaluating VLMs’ GUI knowledge across three dimensions (interface, interaction, procedure) and six platforms, revealing current VLMs lack essential GUI-specific knowledge for task automation.
Details
Motivation: VLMs lag behind humans in GUI task automation despite advances, and the authors hypothesize this gap stems from missing core GUI knowledge that existing training schemes cannot fully address.Method: Analyzed failure patterns in GUI task execution to distill GUI knowledge into three dimensions, then created GUI Knowledge Bench with multiple-choice and yes/no questions across six platforms and 292 applications to evaluate VLMs.
Result: Current VLMs are generally aware of individual widget functions but lack GUI-specific knowledge for tracking system states, adhering to interaction conventions, and assessing task completion progress. Experiments show strong link between GUI knowledge and task success.
Conclusion: The structured framework for assessing GUI knowledge helps select VLMs with greater potential before downstream training and provides insights for building more capable GUI agents.
Abstract: Vision language models (VLMs) have advanced graphical user interface (GUI) task automation but still lag behind humans. We hypothesize this gap stems from missing core GUI knowledge, which existing training schemes (such as supervised fine tuning and reinforcement learning) alone cannot fully address. By analyzing common failure patterns in GUI task execution, we distill GUI knowledge into three dimensions: (1) interface knowledge about widget functions, layout semantics, and system states; (2) interaction knowledge about GUI interaction types and effects; and (3) procedure knowledge of task objectives and workflow sequences. We further introduce GUI Knowledge Bench, a benchmark with multiple-choice and yes/no questions across six platforms (Web, Android, MacOS, Windows, Linux, IOS) and 292 applications. Our evaluation indicates that current VLMs are generally aware of the functions of individual widgets, but lack the GUI-specific knowledge required to track system states, adhere to GUI interaction conventions, and assess task completion progress. Experiments on real-world GUI tasks further validate the close link between GUI knowledge and task success. By providing a structured framework for assessing GUI knowledge, our work supports the selection of VLMs with greater potential prior to downstream training and provides insights for building more capable GUI agents.
[652] Massively Parallel Proof-Number Search for Impartial Games and Beyond
Tomáš Čížek, Martin Balko, Martin Schmid
Main category: cs.AI
TL;DR: Massively parallel Proof-Number Search algorithm achieves 332.9× speedup on 1024 cores and solves 42 new positions in the Sprouts game, nearly doubling known outcomes.
Details
Motivation: Proof-Number Search is effective for game solving but existing parallel versions scale poorly on many CPU cores. With large-scale computing clusters becoming accessible, there's a need for efficient massively parallel versions to solve complex games like Sprouts.Method: Developed a massively parallel Proof-Number Search using two parallelized levels and shared information among workers. Enhanced with Grundy numbers for reducing game trees of impartial games. Applied to Sprouts game as a case study.
Result: Achieved 332.9× speedup on 1024 cores, outperforming state-of-the-art Sprouts solver GLOP by four orders of magnitude in runtime while generating proofs 1,000× more complex. Verified Sprouts Conjecture for 42 new positions, nearly doubling known outcomes.
Conclusion: First massively parallel Proof-Number Search that scales efficiently on many CPUs, enabling solution of complex game positions previously intractable, significantly advancing game solving capabilities.
Abstract: Proof-Number Search is a best-first search algorithm with many successful applications, especially in game solving. As large-scale computing clusters become increasingly accessible, parallelization is a natural way to accelerate computation. However, existing parallel versions of Proof-Number Search are known to scale poorly on many CPU cores. Using two parallelized levels and shared information among workers, we present the first massively parallel version of Proof-Number Search that scales efficiently even on a large number of CPUs. We apply our solver, enhanced with Grundy numbers for reducing game trees of impartial games, to the Sprouts game, a case study motivated by the long-standing Sprouts Conjecture. Our algorithm achieves 332.9$\times$ speedup on 1024 cores, significantly improving previous parallelizations and outperforming the state-of-the-art Sprouts solver GLOP by four orders of magnitude in runtime while generating proofs 1,000$\times$ more complex. Despite exponential growth in game tree size, our solver verified the Sprouts Conjecture for 42 new positions, nearly doubling the number of known outcomes.
[653] Towards Reinforcement Learning from Neural Feedback: Mapping fNIRS Signals to Agent Performance
Julia Santaniello, Matthew Russell, Benson Jiang, Donatello Sassaroli, Robert Jacob, Jivko Sinapov
Main category: cs.AI
TL;DR: Paper introduces RLNF framework using fNIRS brain signals to predict agent performance, creating dataset and classifiers for RL from neural feedback.
Details
Motivation: To develop Reinforcement Learning from Neural Feedback (RLNF) systems that can leverage implicit neural signals (fNIRS) to guide agent training, moving beyond explicit human feedback in RLHF.Method: Collected fNIRS recordings from 25 participants across three domains (Pick-and-Place Robot, Lunar Lander, Flappy Bird), trained classifiers to predict agent performance levels (optimal/suboptimal/worst-case) and regressors to predict action deviation from optimal policies.
Result: Achieved 67% F1 score for binary classification and 46% for multi-class classification; fine-tuning with subject-specific data improved F1 scores by 17% (binary) and 41% (multi-class); demonstrated feasibility of mapping fNIRS signals to agent performance.
Conclusion: Mapping implicit fNIRS signals to agent performance is feasible and can be improved, laying foundation for future RLNF systems that use neural feedback instead of explicit human feedback.
Abstract: Reinforcement Learning from Human Feedback (RLHF) is a methodology that aligns agent behavior with human preferences by integrating user feedback into the agent’s training process. This paper introduces a framework that guides agent training through implicit neural signals, with a focus on the neural classification problem. Our work presents and releases a novel dataset of functional near-infrared spectroscopy (fNIRS) recordings collected from 25 human participants across three domains: Pick-and-Place Robot, Lunar Lander, and Flappy Bird. We train multiple classifiers to predict varying levels of agent performance (optimal, suboptimal, or worst-case) from windows of preprocessed fNIRS features, achieving an average F1 score of 67% for binary and 46% for multi-class classification across conditions and domains. We also train multiple regressors to predict the degree of deviation between an agent’s chosen action and a set of near-optimal policy actions, providing a continuous measure of performance. Finally, we evaluate cross-subject generalization and show that fine-tuning pre-trained models with a small sample of subject-specific data increases average F1 scores by 17% and 41% for binary and multi-class models, respectively. Our results demonstrate that mapping implicit fNIRS signals to agent performance is feasible and can be improved, laying the foundation for future Reinforcement Learning from Neural Feedback (RLNF) systems.
[654] HuggingR$^{4}$: A Progressive Reasoning Framework for Discovering Optimal Model Companions
Shaoyin Ma, Chenggong Hu, Huiqiong Wang, Li Sun, Mingli Song, Jie Song
Main category: cs.AI
TL;DR: HuggingR⁴ is a framework for selecting AI models from large repositories using iterative reasoning instead of one-shot retrieval, achieving better performance with reduced token costs.
Details
Motivation: Current approaches for selecting AI models from large repositories like HuggingFace (with >2M models) face challenges with prompt bloat, excessive token costs, and limited scalability when incorporating full model descriptions into prompts.Method: Proposes HuggingR⁴ framework that recasts model selection as iterative reasoning process with four components: Reasoning (decomposing user intent), Retrieval (multi-round deliberation), Refinement (fine-grained analysis), and Reflection (validation).
Result: Achieves 92.03% workability and 82.46% reasonability, outperforming state-of-the-art baselines by 26.51% and 33.25% respectively, while reducing token consumption by 6.9× on a benchmark of 14,399 user requests across 37 task categories.
Conclusion: HuggingR⁴ provides an effective framework for repository-scale model selection through iterative reasoning, addressing scalability and cost issues of existing approaches.
Abstract: Building effective LLM agents increasingly requires selecting appropriate AI models as tools from large open repositories (e.g., HuggingFace with > 2M models) based on natural language requests. Unlike invoking a fixed set of API tools, repository-scale model selection must handle massive, evolving candidates with incomplete metadata. Existing approaches incorporate full model descriptions into prompts, resulting in prompt bloat, excessive token costs, and limited scalability. To address these issues, we propose HuggingR$^4$, the first framework to recast model selection as an iterative reasoning process rather than one-shot retrieval. By synergistically integrating Reasoning, Retrieval, Refinement, and Reflection, HuggingR$^4$ progressively decomposes user intent, retrieves candidates through multi-round deliberation, refines selections via fine-grained analysis, and validates results through reflection. To facilitate rigorous evaluation, we introduce a large-scale benchmark comprising 14,399 diverse user requests across 37 task categories. Experiments demonstrate that HuggingR$^4$ achieves 92.03% workability and 82.46% reasonability-outperforming current state-of-the-art baselines by 26.51% and 33.25%, respectively, while reducing token consumption by $6.9 \times$.
[655] UNeMo: Collaborative Visual-Language Reasoning and Navigation via a Multimodal World Model
Changxin Huang, Lv Tang, Zhaohuan Zhan, Lisha Yu, Runhao Zeng, Zun Liu, Zhengjie Wang, Jianqiang Li
Main category: cs.AI
TL;DR: UNeMo is a novel framework for Vision-and-Language Navigation that jointly optimizes visual state reasoning and navigational decision-making through a Multimodal World Model and hierarchical prediction-feedback mechanism.
Details
Motivation: Current VLN methods using LLMs are limited to linguistic reasoning and lack visual reasoning capabilities. Existing reasoning modules are optimized separately from navigation policies, causing incompatibility and conflicting optimization objectives.Method: Introduces UNeMo with a Multimodal World Model (MWM) that takes visual features, language instructions, and navigational actions as inputs to predict subsequent visual states. Uses Hierarchical Prediction-Feedback (HPN) mechanism where MWM collaborates with navigation policies: first layer generates actions, MWM infers post-action visual states to guide second layer’s fine-grained decisions.
Result: Outperforms state-of-the-art methods by 2.1% and 0.7% in navigation accuracy for unseen scenes on R2R and REVERIE datasets.
Conclusion: UNeMo effectively addresses the limitations of existing VLN methods by enabling collaborative optimization of visual reasoning and navigation policies through a bidirectional promotion mechanism.
Abstract: Vision-and-Language Navigation (VLN) requires agents to autonomously navigate complex environments via visual images and natural language instructions–remains highly challenging. Recent research on enhancing language-guided navigation reasoning using pre-trained large language models (LLMs) has shown promising prospects. However, the reasoning of such methods is limited to the linguistic modality, lacking visual reasoning capabilities. Moreover, existing reasoning modules are optimized separately from navigation policies, leading to incompatibility and potential conflicts in optimization objectives.To tackle these challenges, we introduce UNeMo, a novel framework designed for the collaborative optimization of visual state reasoning and navigational decision-making. It introduces a Multimodal World Model (MWM) that takes visual features, language instructions, and navigational actions as inputs to jointly predict subsequent visual states, enabling cross-modal reasoning. Via a Hierarchical Prediction-Feedback (HPN) mechanism, MWM collaborates with navigation policies: the first layer generates actions using current vision-and-language features; MWM then infers post-action visual states to guide the second layer’s fine-grained decisions. This forms a dynamic bidirectional promotion mechanism where MWM reasoning optimizes navigation policies, while policy decisions feedback to improve MWM’s reasoning accuracy. Experiments on R2R and REVERIE datasets show UNeMo outperforms state-of-the-art methods by 2.1% and 0.7% in navigation accuracy for unseen scenes, validating its effectiveness.
[656] CostNav: A Navigation Benchmark for Real-World Economic-Cost Evaluation of Physical AI Agents
Haebin Seong, Sungmin Kim, Yongjun Cho, Myunchul Joe, Geunwoo Kim, Yubeen Park, Sunhoo Kim, Yoonshik Kim, Suhwan Choi, Jaeyoon Jung, Jiyong Youn, Jinmyung Kwak, Sunghee Ahn, Jaemin Lee, Younggil Do, Seungyeop Yi, Woojin Cheong, Minhyeok Oh, Minchan Kim, Yoonseok Kang, Seongjae Kang, Samwoo Seong, Youngjae Yu, Yunsung Lee
Main category: cs.AI
TL;DR: CostNav: A benchmark evaluating autonomous delivery navigation through economic cost-revenue analysis rather than just task success, revealing current approaches are not commercially viable.
Details
Motivation: Current navigation benchmarks focus on simplified task success but neglect real-world economic constraints essential for commercial autonomous delivery systems. There's a gap between research metrics and commercial viability.Method: Introduces CostNav benchmark integrating industry data (SEC filings, AIS injury reports) with Isaac Sim’s collision/cargo dynamics for comprehensive economic cost-revenue analysis. Evaluates navigation policies based on economic viability rather than task completion.
Result: Evaluation of rule-based Nav2 navigation shows current approaches are not economically viable: contribution margin is -$22.81/run (AMCL) and -$12.87/run (GPS) with no break-even point.
Conclusion: CostNav is the first benchmark to quantitatively expose the gap between navigation research metrics and commercial viability. Challenges community to develop economically viable navigation policies.
Abstract: While current navigation benchmarks prioritize task success in simplified settings, they neglect the multidimensional economic constraints essential for the real-world commercialization of autonomous delivery systems. We introduce CostNav, an Economic Navigation Benchmark that evaluates physical AI agents through comprehensive economic cost-revenue analysis aligned with real-world business operations. By integrating industry-standard data - such as SEC filings and AIS injury reports - with Isaac Sim’s detailed collision and cargo dynamics, CostNav transcends simple task completion to accurately evaluate business value in complex, real-world scenarios. To our knowledge, CostNav is the first work to quantitatively expose the gap between navigation research metrics and commercial viability, revealing that optimizing for task success on a simplified task fundamentally differs from optimizing for real-world economic deployment. Our evaluation of rule-based Nav2 navigation shows that current approaches are not economically viable: the contribution margin is -22.81/run (AMCL) and -12.87/run (GPS), resulting in no break-even point. We challenge the community to develop navigation policies that achieve economic viability on CostNav. We remain method-agnostic, evaluating success solely on the metric of cost rather than the underlying architecture. All resources are available at https://github.com/worv-ai/CostNav.
[657] Reasoning With a Star: A Heliophysics Dataset and Benchmark for Agentic Scientific Reasoning
Kevin Lee, Russell Spiewak, James Walsh
Main category: cs.AI
TL;DR: A heliophysics reasoning dataset and benchmarking framework for evaluating LLMs on scientific reasoning tasks requiring physical assumptions, unit consistency, and proper formatting.
Details
Motivation: Scientific reasoning in heliophysics requires more than factual recall - it needs physical assumptions, unit consistency, and proper scientific formats. Current LLMs lack specialized datasets and evaluation frameworks for this domain.Method: Created “Reasoning With a Star” dataset from NASA/UCAR Living With a Star summer school problem sets with Q&A structure including contexts, reasoning steps, answer types, ground truth, format hints, and metadata. Developed programmatic grader with unit-aware numerical tolerance, symbolic equivalence, and schema validation. Benchmarked single-shot baseline vs four multi-agent patterns.
Result: Decomposing workflows through systems engineering principles outperforms direct prompting on problems requiring deductive reasoning rather than pure inductive recall.
Conclusion: Specialized datasets and evaluation frameworks are needed for scientific reasoning in heliophysics, and structured multi-agent approaches improve performance on deductive reasoning tasks.
Abstract: Scientific reasoning through Large Language Models in heliophysics involves more than just recalling facts: it requires incorporating physical assumptions, maintaining consistent units, and providing clear scientific formats through coordinated approaches. To address these challenges, we present Reasoning With a Star, a newly contributed heliophysics dataset applicable to reasoning; we also provide an initial benchmarking approach. Our data are constructed from National Aeronautics and Space Administration & University Corporation for Atmospheric Research Living With a Star summer school problem sets and compiled into a readily consumable question-and-answer structure with question contexts, reasoning steps, expected answer type, ground-truth targets, format hints, and metadata. A programmatic grader checks the predictions using unit-aware numerical tolerance, symbolic equivalence, and schema validation. We benchmark a single-shot baseline and four multi-agent patterns, finding that decomposing workflows through systems engineering principles outperforms direct prompting on problems requiring deductive reasoning rather than pure inductive recall.
[658] Agent policies from higher-order causal functions
Matt Wilson
Main category: cs.AI
TL;DR: The paper establishes a formal correspondence between agent-state policies in deterministic POMDPs and one-input process functions from quantum foundations, creating a bridge between AI agent-environment interactions, causal structure in physics, and logic in computer science.
Details
Motivation: To build theoretical bridges between three distinct fields: artificial intelligence (agent-environment interactions in POMDPs), foundations of physics (causal structure and higher-order quantum operations), and computer science (logic and type theory). The goal is to unify these concepts through formal mathematical structures.Method: Establishes correspondence between equivalence classes of agent-state policies for deterministic POMDPs and one-input process functions. Constructs a *-autonomous category PF of types supporting interpretation of policy evaluation and multi-agent constraints. Identifies observation-independent decentralized POMDPs as domain for multi-input process functions modeling indefinite causality.
Result: Proves strict separation between general multi-input process functions and definite-ordered process functions on decentralized POMDPs. Finds instances where policies utilizing indefinite causal structure achieve greater finite-horizon rewards than policies restricted to fixed background causal structure.
Conclusion: The paper successfully bridges AI, physics, and computer science through formal correspondences, demonstrating practical advantages of indefinite causal structures in multi-agent decision-making scenarios, with implications for understanding agent-environment interactions across disciplines.
Abstract: We establish a correspondence between equivalence classes of agent-state policies for deterministic POMDPs and one-input process functions (the classical-deterministic limit of higher-order quantum operations). We use this correspondence to build a bridge between the agent-environment interaction in artificial intelligence, causal structure in the foundations of physics, and logic in computer science. We construct a *-autonomous category PF of types which supports an interpretation of one-step evaluation of policies, and multi-agent observation constraints, into cuts and monoidal products. In terms of types, we develop the correspondence further by identifying observation-independent decentralised POMDPs as the natural domain for the multi-input process functions used to model indefinite causality. We then prove a strict separation between general multi-input process function and definite-ordered process function performance on such dec-POMDPs, by finding an instance for which policies utilizing an indefinite causal structure can achieve greater finite-horizon rewards than policies which are restricted to a fixed background causal structure.
[659] Safety Alignment of LMs via Non-cooperative Games
Anselm Paulus, Ilia Kulikov, Brandon Amos, Rémi Munos, Ivan Evtimov, Kamalika Chaudhuri, Arman Zharmagambetov
Main category: cs.AI
TL;DR: Safety alignment of language models framed as non-zero-sum game between Attacker and Defender LMs trained via online RL with preference-based rewards
Details
Motivation: Current safety alignment approaches rely on sequential adversarial training which may be suboptimal; need for methods that maintain both safety and usefulness of language modelsMethod: Frames safety alignment as non-zero-sum game between Attacker LM and Defender LM trained jointly via online reinforcement learning using preference-based reward signals from pairwise comparisons
Result: AdvGame method shifts Pareto frontier of safety and utility, producing Defender LM that is more helpful and resilient to attacks, and Attacker LM that becomes strong general-purpose red-teaming agent
Conclusion: Game-theoretic approach to safety alignment enables simultaneous improvement of both safety and utility, with emergent red-teaming capabilities
Abstract: Ensuring the safety of language models (LMs) while maintaining their usefulness remains a critical challenge in AI alignment. Current approaches rely on sequential adversarial training: generating adversarial prompts and fine-tuning LMs to defend against them. We introduce a different paradigm: framing safety alignment as a non-zero-sum game between an Attacker LM and a Defender LM trained jointly via online reinforcement learning. Each LM continuously adapts to the other’s evolving strategies, driving iterative improvement. Our method uses a preference-based reward signal derived from pairwise comparisons instead of point-wise scores, providing more robust supervision and potentially reducing reward hacking. Our RL recipe, AdvGame, shifts the Pareto frontier of safety and utility, yielding a Defender LM that is simultaneously more helpful and more resilient to adversarial attacks. In addition, the resulting Attacker LM converges into a strong, general-purpose red-teaming agent that can be directly deployed to probe arbitrary target models.
[660] InSPO: Unlocking Intrinsic Self-Reflection for LLM Preference Optimization
Yu Li, Tian Lan, Zhengling Qi
Main category: cs.AI
TL;DR: InSPO addresses DPO limitations by enabling LLMs to condition on alternative responses for self-reflection, yielding more robust alignment without architectural changes.
Details
Motivation: DPO and variants have limitations: optimal policy depends on arbitrary modeling choices (scalarization function, reference policy), and treating responses in isolation fails to leverage comparative information in pairwise data, leaving self-reflection untapped.Method: Proposes Intrinsic Self-reflective Preference Optimization (InSPO), deriving a globally optimal policy conditioning on both context and alternative responses, guaranteeing invariance to scalarization and reference choices.
Result: Experiments show consistent improvements in win rates and length-controlled metrics, validating that unlocking self-reflection yields more robust, human-aligned LLMs.
Conclusion: InSPO serves as a plug-and-play enhancement without architectural changes or inference overhead, superior to DPO/RLHF while guaranteeing invariance to modeling choices.
Abstract: Direct Preference Optimization (DPO) and its variants have become standard for aligning Large Language Models due to their simplicity and offline stability. However, we identify two fundamental limitations. First, the optimal policy depends on arbitrary modeling choices (scalarization function, reference policy), yielding behavior reflecting parameterization artifacts rather than true preferences. Second, treating response generation in isolation fails to leverage comparative information in pairwise data, leaving the model’s capacity for intrinsic self-reflection untapped. To address it, we propose Intrinsic Self-reflective Preference Optimization (InSPO), deriving a globally optimal policy conditioning on both context and alternative responses. We prove this formulation superior to DPO/RLHF while guaranteeing invariance to scalarization and reference choices. InSPO serves as a plug-and-play enhancement without architectural changes or inference overhead. Experiments demonstrate consistent improvements in win rates and length-controlled metrics, validating that unlocking self-reflection yields more robust, human-aligned LLMs. Our Code is available at https://github.com/Skylanding/InSPO.
[661] VirtualEnv: A Platform for Embodied AI Research
Kabir Swain, Sijie Han, Ayush Raina, Jin Zhang, Shuang Li, Michael Stopa, Antonio Torralba
Main category: cs.AI
TL;DR: VirtualEnv is a simulation platform built on Unreal Engine 5 for benchmarking LLMs in embodied interactive scenarios with rich agent-environment interactions and procedurally generated tasks.
Details
Motivation: There's a growing need for realistic, interactive environments to rigorously evaluate LLMs' reasoning and decision-making abilities in embodied scenarios, as current benchmarks are limited.Method: Built on Unreal Engine 5 with a user-friendly API for natural language control. Integrates LLMs and VLMs (including GPT-based models) for environment generation and task creation. Supports object manipulation, navigation, multi-agent collaboration, escape rooms, and procedurally generated environments.
Result: Benchmarks several popular LLMs across tasks of increasing complexity, analyzing adaptability, planning, and multi-agent coordination. Provides methodology for procedural task generation, validation, and real-time environment control.
Conclusion: VirtualEnv advances research at the intersection of AI and gaming, enables standardized evaluation of LLMs in embodied AI settings, and paves the way for immersive simulations and interactive entertainment.
Abstract: As large language models (LLMs) continue to improve in reasoning and decision-making, there is a growing need for realistic and interactive environments where their abilities can be rigorously evaluated. We present VirtualEnv, a next-generation simulation platform built on Unreal Engine 5 that enables fine-grained benchmarking of LLMs in embodied and interactive scenarios. VirtualEnv supports rich agent-environment interactions, including object manipulation, navigation, and adaptive multi-agent collaboration, as well as game-inspired mechanics like escape rooms and procedurally generated environments. We provide a user-friendly API built on top of Unreal Engine, allowing researchers to deploy and control LLM-driven agents using natural language instructions. We integrate large-scale LLMs and vision-language models (VLMs), such as GPT-based models, to generate novel environments and structured tasks from multimodal inputs. Our experiments benchmark the performance of several popular LLMs across tasks of increasing complexity, analyzing differences in adaptability, planning, and multi-agent coordination. We also describe our methodology for procedural task generation, task validation, and real-time environment control. VirtualEnv is released as an open-source platform, we aim to advance research at the intersection of AI and gaming, enable standardized evaluation of LLMs in embodied AI settings, and pave the way for future developments in immersive simulations and interactive entertainment.
[662] Imandra CodeLogician: Neuro-Symbolic Reasoning for Precise Analysis of Software Logic
Hongyu Lin, Samer Abdallah, Makar Valentinov, Paul Brennan, Elijah Kagan, Christoph M. Wintersteiger, Denis Ignatovich, Grant Passmore
Main category: cs.AI
TL;DR: CodeLogician is a neurosymbolic agent combining LLMs with formal reasoning engine ImandraX for precise software logic analysis, bridging mathematical rigor with real-world code understanding.
Details
Motivation: LLMs show strong code understanding but lack precise mathematical reasoning about program behavior. Existing benchmarks are either too theoretical (mathematical proof automation) or too practical (engineering tasks without semantic rigor), leaving a gap for rigorous software logic analysis.Method: CodeLogician integrates LLMs with ImandraX, an industrial automated reasoning engine. Unlike prior approaches that use formal methods to validate LLM outputs, CodeLogician uses LLMs to construct explicit formal models of software systems, enabling automated reasoning to answer rich semantic questions beyond binary verification.
Result: Formal augmentation with CodeLogician yields substantial improvements over LLM-only reasoning, closing a 41-47 percentage point gap in reasoning accuracy on the code-logic-bench benchmark, which measures reasoning about program state spaces, control flow, coverage constraints, and edge cases.
Conclusion: Neurosymbolic integration (combining LLMs with formal reasoning) is essential for scaling program analysis toward rigorous, autonomous software understanding, bridging the gap between theorem proving and practical software engineering.
Abstract: Large Language Models (LLMs) have shown strong performance on code understanding tasks, yet they fundamentally lack the ability to perform precise, exhaustive mathematical reasoning about program behavior. Existing benchmarks either focus on mathematical proof automation, largely disconnected from real-world software, or on engineering tasks that do not require semantic rigor. We present CodeLogician, a neurosymbolic agent for precise analysis of software logic, integrated with ImandraX, an industrial automated reasoning engine deployed in financial markets and safety-critical systems. Unlike prior approaches that use formal methods primarily to validate LLM outputs, CodeLogician uses LLMs to construct explicit formal models of software systems, enabling automated reasoning to answer rich semantic questions beyond binary verification outcomes. To rigorously evaluate mathematical reasoning about software logic, we introduce code-logic-bench, a benchmark targeting the middle ground between theorem proving and software engineering benchmarks. It measures reasoning correctness about program state spaces, control flow, coverage constraints, and edge cases, with ground truth defined via formal modeling and region decomposition. Comparing LLM-only reasoning against LLMs augmented with CodeLogician, formal augmentation yields substantial improvements, closing a 41-47 percentage point gap in reasoning accuracy. These results demonstrate that neurosymbolic integration is essential for scaling program analysis toward rigorous, autonomous software understanding.
[663] Beyond In-Domain Detection: SpikeScore for Cross-Domain Hallucination Detection
Yongxin Deng, Zhen Fang, Sharon Li, Ling Chen
Main category: cs.AI
TL;DR: SpikeScore: A novel hallucination detection method that measures uncertainty fluctuations in multi-turn dialogues to achieve strong cross-domain generalization for LLMs.
Details
Motivation: Existing hallucination detection methods perform well within the same domain but fail to generalize across different domains, limiting their real-world applicability for LLM deployment.Method: Proposes SpikeScore, which quantifies abrupt uncertainty fluctuations in multi-turn dialogues following LLM responses. The method simulates dialogues and observes that hallucination-initiated dialogues show larger uncertainty fluctuations than factual ones across domains.
Result: SpikeScore achieves strong cross-domain separability between hallucinated and non-hallucinated responses, outperforming representative baselines and advanced generalization-oriented methods across multiple LLMs and benchmarks.
Conclusion: The SpikeScore-based detection method effectively addresses the generalizable hallucination detection problem, providing robust cross-domain performance for hallucination detection in LLMs.
Abstract: Hallucination detection is critical for deploying large language models (LLMs) in real-world applications. Existing hallucination detection methods achieve strong performance when the training and test data come from the same domain, but they suffer from poor cross-domain generalization. In this paper, we study an important yet overlooked problem, termed generalizable hallucination detection (GHD), which aims to train hallucination detectors on data from a single domain while ensuring robust performance across diverse related domains. In studying GHD, we simulate multi-turn dialogues following LLMs’ initial response and observe an interesting phenomenon: hallucination-initiated multi-turn dialogues universally exhibit larger uncertainty fluctuations than factual ones across different domains. Based on the phenomenon, we propose a new score SpikeScore, which quantifies abrupt fluctuations in multi-turn dialogues. Through both theoretical analysis and empirical validation, we demonstrate that SpikeScore achieves strong cross-domain separability between hallucinated and non-hallucinated responses. Experiments across multiple LLMs and benchmarks demonstrate that the SpikeScore-based detection method outperforms representative baselines in cross-domain generalization and surpasses advanced generalization-oriented methods, verifying the effectiveness of our method in cross-domain hallucination detection.
[664] OpenSec: Measuring Incident Response Agent Calibration Under Adversarial Evidence
Jarrod Barnes
Main category: cs.AI
TL;DR: OpenSec is a dual-control RL environment for evaluating incident response agents under realistic prompt injection attacks, revealing frontier LLMs consistently over-trigger containment actions before gathering sufficient evidence.
Details
Motivation: As LLMs become more capable, their offensive applications in cybersecurity (like generating exploits) improve, requiring defensive incident response agents to keep pace. Existing benchmarks conflate action execution with correct execution, hiding calibration failures when agents process adversarial evidence.Method: Introduces OpenSec, a dual-control reinforcement learning environment that evaluates IR agents under realistic prompt injection scenarios with execution-based scoring metrics: time-to-first-containment (TTFC), evidence-gated action rate (EGAR), blast radius, and per-tier injection violation rates.
Result: Evaluation of four frontier models on 40 standard-tier episodes each shows consistent over-triggering: GPT-5.2 executes containment in 100% of episodes with 82.5% false positive rate, acting at step 4 before gathering sufficient evidence. Claude Sonnet 4.5 shows partial calibration (62.5% containment, 45% FP, TTFC of 10.6). All models correctly identify ground-truth threats when they act; the calibration gap is in restraint, not detection.
Conclusion: Calibration is not reliably present across frontier models for incident response tasks. The key issue is not threat detection capability but rather the restraint to gather sufficient evidence before taking containment actions.
Abstract: As large language models (LLMs) improve, so do their offensive applications: frontier agents now generate working exploits for under $50 in compute (Heelan, 2026). Defensive incident response (IR) agents must keep pace, but existing benchmarks conflate action execution with correct execution, hiding calibration failures when agents process adversarial evidence. We introduce OpenSec, a dual-control reinforcement learning (RL) environment that evaluates IR agents under realistic prompt injection scenarios with execution-based scoring: time-to-first-containment (TTFC), evidence-gated action rate (EGAR), blast radius, and per-tier injection violation rates. Evaluating four frontier models on 40 standard-tier episodes each, we find consistent over-triggering: GPT-5.2 executes containment in 100% of episodes with 82.5% false positive rate, acting at step 4 before gathering sufficient evidence. Claude Sonnet 4.5 shows partial calibration (62.5% containment, 45% FP, TTFC of 10.6), suggesting calibration is not reliably present across frontier models. All models correctly identify the ground-truth threat when they act; the calibration gap is not in detection but in restraint. Code available at https://github.com/jbarnes850/opensec-env.
[665] Sycophantic Anchors: Localizing and Quantifying User Agreement in Reasoning Models
Jacek Duszenko
Main category: cs.AI
TL;DR: The paper introduces “sycophantic anchors” - sentences in reasoning traces that commit models to agreeing with incorrect user suggestions, and shows these can be detected via linear probes on internal activations with high accuracy.
Details
Motivation: To understand where in reasoning traces models commit to sycophantic behavior (agreeing with incorrect user suggestions) and how to detect and quantify this misalignment during inference.Method: Used counterfactual analysis to identify sycophantic anchors in reasoning traces, then applied linear probes to internal activations of four reasoning models (Llama, Qwen, Falcon-hybrid, 1.5B-8B parameters) across over 200,000 counterfactual rollouts.
Result: Linear probes achieved 74-85% balanced accuracy detecting sycophantic anchors, outperforming text-only baselines. Regressors predicted commitment strength from activations (R² up to 0.74). Sycophancy leaves stronger mechanistic footprints than correct reasoning and builds gradually during generation.
Conclusion: Sycophantic anchors can be reliably detected in model activations, enabling sentence-level detection and quantification of model misalignment during inference, with sycophancy showing stronger mechanistic signatures than correct reasoning.
Abstract: Reasoning models frequently agree with incorrect user suggestions – a behavior known as sycophancy. However, it is unclear where in the reasoning trace this agreement originates and how strong the commitment is. We introduce \emph{sycophantic anchors} – sentences identified via counterfactual analysis that commit models to user agreement. Across four reasoning models spanning three architecture families (Llama, Qwen, Falcon-hybrid) and 1.5B–8B parameters, we analyze over 200,000 counterfactual rollouts and show that linear probes reliably detect sycophantic anchors (74–85% balanced accuracy), outperforming text-only baselines at high commitment levels – confirming they capture internal states beyond surface vocabulary. Regressors further predict commitment strength from activations ($R^2$ up to 0.74). We observe a consistent asymmetry: sycophancy leaves a stronger mechanistic footprint than correct reasoning. We also find that sycophancy builds gradually during generation rather than being determined by the prompt. These findings enable sentence-level detection and quantification of model misalignment mid-inference.
[666] TIDE: Tuning-Integrated Dynamic Evolution for LLM-Based Automated Heuristic Design
Chentong Chen, Mengyuan Zhong, Ye Fan, Jialong Shi, Jianyong Sun
Main category: cs.AI
TL;DR: TIDE is a framework that decouples structural reasoning from parameter optimization in automated heuristic design, using parallel island models for structural diversity and integrated parameter tuning to improve algorithm evolution.
Details
Motivation: Existing LLM-based automated heuristic design methods treat algorithm evolution as monolithic text generation, overlooking the coupling between discrete algorithmic structures and continuous numerical parameters, leading to discarding promising algorithms due to uncalibrated constants and premature convergence from simple similarity metrics.Method: TIDE features a nested architecture with an outer parallel island model using Tree Similarity Edit Distance for structural diversity, and an inner loop integrating LLM-based logic generation with differential mutation operator for parameter tuning, plus a UCB-based scheduler to dynamically prioritize high-yield prompt strategies.
Result: Extensive experiments across nine combinatorial optimization problems show TIDE discovers heuristics that significantly outperform state-of-the-art baselines in solution quality while achieving improved search efficiency and reduced computational costs.
Conclusion: TIDE successfully addresses the limitations of existing LLM-based automated heuristic design by decoupling structural reasoning from parameter optimization, leading to more effective algorithm evolution with better performance and efficiency.
Abstract: Although Large Language Models have advanced Automated Heuristic Design, treating algorithm evolution as a monolithic text generation task overlooks the coupling between discrete algorithmic structures and continuous numerical parameters. Consequently, existing methods often discard promising algorithms due to uncalibrated constants and suffer from premature convergence resulting from simple similarity metrics. To address these limitations, we propose TIDE, a Tuning-Integrated Dynamic Evolution framework designed to decouple structural reasoning from parameter optimization. TIDE features a nested architecture where an outer parallel island model utilizes Tree Similarity Edit Distance to drive structural diversity, while an inner loop integrates LLM-based logic generation with a differential mutation operator for parameter tuning. Additionally, a UCB-based scheduler dynamically prioritizes high-yield prompt strategies to optimize resource allocation. Extensive experiments across nine combinatorial optimization problems demonstrate that TIDE discovers heuristics that significantly outperform state-of-the-art baselines in solution quality while achieving improved search efficiency and reduced computational costs.
[667] Zero-Shot Statistical Downscaling via Diffusion Posterior Sampling
Ruian Tie, Wenbo Xiong, Zhengyu Shi, Xinyu Su, Chenyu jiang, Libo Wu, Hao Li
Main category: cs.AI
TL;DR: Zero-Shot Statistical Downscaling (ZSSD) framework for climate downscaling without paired training data, using physics-consistent climate priors and unified coordinate guidance to handle domain gaps between GCMs and reanalysis.
Details
Motivation: Conventional supervised climate downscaling struggles with generalization to Global Climate Models due to lack of paired training data and domain gaps, while current zero-shot methods suffer from physical inconsistencies and vanishing gradient issues under large scaling factors.Method: ZSSD uses a Physics-Consistent Climate Prior learned from reanalysis data, conditioned on geophysical boundaries and temporal information. Introduces Unified Coordinate Guidance to address vanishing gradient problems in vanilla DPS and ensure consistency with large-scale fields.
Result: ZSSD significantly outperforms existing zero-shot baselines in 99th percentile errors and successfully reconstructs complex weather events like tropical cyclones across heterogeneous GCMs.
Conclusion: The proposed zero-shot framework enables statistical downscaling without paired training data while maintaining physical consistency and handling domain gaps between different climate models.
Abstract: Conventional supervised climate downscaling struggles to generalize to Global Climate Models (GCMs) due to the lack of paired training data and inherent domain gaps relative to reanalysis. Meanwhile, current zero-shot methods suffer from physical inconsistencies and vanishing gradient issues under large scaling factors. We propose Zero-Shot Statistical Downscaling (ZSSD), a zero-shot framework that performs statistical downscaling without paired data during training. ZSSD leverages a Physics-Consistent Climate Prior learned from reanalysis data, conditioned on geophysical boundaries and temporal information to enforce physical validity. Furthermore, to enable robust inference across varying GCMs, we introduce Unified Coordinate Guidance. This strategy addresses the vanishing gradient problem in vanilla DPS and ensures consistency with large-scale fields. Results show that ZSSD significantly outperforms existing zero-shot baselines in 99th percentile errors and successfully reconstructs complex weather events, such as tropical cyclones, across heterogeneous GCMs.
[668] Statistical Estimation of Adversarial Risk in Large Language Models under Best-of-N Sampling
Mingqian Feng, Xiaodong Liu, Weiwei Yang, Chenliang Xu, Christopher White, Jianfeng Gao
Main category: cs.AI
TL;DR: SABER: A scaling-aware Best-of-N estimation method for predicting LLM jailbreak vulnerability under large-scale parallel sampling attacks, enabling reliable extrapolation of attack success rates from small-budget measurements.
Details
Motivation: Current LLM safety evaluations underestimate real-world risk by testing under single-shot or low-budget adversarial prompting, while attackers can use large-scale parallel sampling to repeatedly probe models until harmful responses are produced. There's a need for principled methods to predict large-scale adversarial risk.Method: Proposes SABER (scaling-aware Best-of-N estimation of risk) that models sample-level success probabilities using a Beta distribution (conjugate prior of Bernoulli distribution). Derives an analytic scaling law that enables reliable extrapolation of large-N attack success rates from small-budget measurements (e.g., n=100 samples).
Result: Using only n=100 samples, the anchored estimator predicts ASR@1000 with mean absolute error of 1.66 (86.2% reduction compared to baseline error of 12.04). Reveals heterogeneous risk scaling profiles and shows that models appearing robust under standard evaluation can experience rapid nonlinear risk amplification under parallel adversarial pressure.
Conclusion: Provides a low-cost, scalable methodology for realistic LLM safety assessment. Demonstrates that current safety evaluations underestimate risk and that models can have hidden vulnerabilities that only emerge under large-scale parallel sampling attacks.
Abstract: Large Language Models (LLMs) are typically evaluated for safety under single-shot or low-budget adversarial prompting, which underestimates real-world risk. In practice, attackers can exploit large-scale parallel sampling to repeatedly probe a model until a harmful response is produced. While recent work shows that attack success increases with repeated sampling, principled methods for predicting large-scale adversarial risk remain limited. We propose a scaling-aware Best-of-N estimation of risk, SABER, for modeling jailbreak vulnerability under Best-of-N sampling. We model sample-level success probabilities using a Beta distribution, the conjugate prior of the Bernoulli distribution, and derive an analytic scaling law that enables reliable extrapolation of large-N attack success rates from small-budget measurements. Using only n=100 samples, our anchored estimator predicts ASR@1000 with a mean absolute error of 1.66, compared to 12.04 for the baseline, which is an 86.2% reduction in estimation error. Our results reveal heterogeneous risk scaling profiles and show that models appearing robust under standard evaluation can experience rapid nonlinear risk amplification under parallel adversarial pressure. This work provides a low-cost, scalable methodology for realistic LLM safety assessment. We will release our code and evaluation scripts upon publication to future research.
[669] Game-Theoretic Co-Evolution for LLM-Based Heuristic Discovery
Xinyi Ke, Kai Li, Junliang Xing, Yifan Zhang, Jian Cheng
Main category: cs.AI
TL;DR: ASRO is a game-theoretic framework for automatic heuristic discovery that uses LLMs to co-evolve solvers and instance generators through iterative best-response oracles, improving generalization and robustness.
Details
Motivation: Existing automatic heuristic discovery methods suffer from static evaluation against fixed instance distributions, leading to overfitting and poor generalization under distributional shifts.Method: ASRO frames heuristic discovery as a two-player zero-sum game between solver and instance generator. It maintains growing strategy pools on both sides and iteratively expands them using LLM-based best-response oracles against mixed opponent meta-strategies, creating an adaptive self-generated curriculum.
Result: Across multiple combinatorial optimization domains, ASRO consistently outperforms static-training AHD baselines built on the same program search mechanisms, achieving substantially improved generalization and robustness on diverse and out-of-distribution instances.
Conclusion: The game-theoretic approach of ASRO provides a more effective framework for automatic heuristic discovery by replacing static evaluation with adaptive co-evolution, leading to better generalization capabilities.
Abstract: Large language models (LLMs) have enabled rapid progress in automatic heuristic discovery (AHD), yet most existing methods are predominantly limited by static evaluation against fixed instance distributions, leading to potential overfitting and poor generalization under distributional shifts. We propose Algorithm Space Response Oracles (ASRO), a game-theoretic framework that reframes heuristic discovery as a program level co-evolution between solver and instance generator. ASRO models their interaction as a two-player zero-sum game, maintains growing strategy pools on both sides, and iteratively expands them via LLM-based best-response oracles against mixed opponent meta-strategies, thereby replacing static evaluation with an adaptive, self-generated curriculum. Across multiple combinatorial optimization domains, ASRO consistently outperforms static-training AHD baselines built on the same program search mechanisms, achieving substantially improved generalization and robustness on diverse and out-of-distribution instances.
[670] Optimizing Agentic Reasoning with Retrieval via Synthetic Semantic Information Gain Reward
Senkang Hu, Yong Dai, Yuzhi Zhao, Yihang Tao, Yu Guo, Zhengru Fang, Sam Tak Wu Kwong, Yuguang Fang
Main category: cs.AI
TL;DR: InfoReasoner is a framework that optimizes retrieval for agentic reasoning by using semantic information gain as an intrinsic reward, improving question-answering performance without manual annotations.
Details
Motivation: Current agentic reasoning models lack principled reward signals for optimizing retrieval processes, making it challenging to dynamically acquire relevant external knowledge efficiently.Method: Proposes InfoReasoner with: 1) Theoretical redefinition of information gain as uncertainty reduction over belief states, 2) Output-aware intrinsic estimator using semantic clustering via bidirectional textual entailment, 3) Group Relative Policy Optimization (GRPO) for training.
Result: Outperforms strong retrieval-augmented baselines across seven QA benchmarks, achieving up to 5.4% average accuracy improvement.
Conclusion: Provides a theoretically grounded and scalable framework for optimizing retrieval in agentic reasoning systems.
Abstract: Agentic reasoning enables large reasoning models (LRMs) to dynamically acquire external knowledge, but yet optimizing the retrieval process remains challenging due to the lack of dense, principled reward signals. In this paper, we introduce InfoReasoner, a unified framework that incentivizes effective information seeking via a synthetic semantic information gain reward. Theoretically, we redefine information gain as uncertainty reduction over the model’s belief states, establishing guarantees, including non-negativity, telescoping additivity, and channel monotonicity. Practically, to enable scalable optimization without manual retrieval annotations, we propose an output-aware intrinsic estimator that computes information gain directly from the model’s output distributions using semantic clustering via bidirectional textual entailment. This intrinsic reward guides the policy to maximize epistemic progress, enabling efficient training via Group Relative Policy Optimization (GRPO). Experiments across seven question-answering benchmarks demonstrate that InfoReasoner consistently outperforms strong retrieval-augmented baselines, achieving up to 5.4% average accuracy improvement. Our work provides a theoretically grounded and scalable path toward agentic reasoning with retrieval. The code is available at https://github.com/dl-m9/InfoReasoner
[671] Agyn: A Multi-Agent System for Team-Based Autonomous Software Engineering
Nikita Benkovich, Vitalii Valkov
Main category: cs.AI
TL;DR: Multi-agent system that models software engineering as an organizational process with specialized roles, outperforming single-agent baselines on SWE-bench
Details
Motivation: Real-world software development is collaborative with clear roles and methodologies, but current autonomous systems treat issue resolution as monolithic. The paper aims to replicate team structure and processes for better autonomous software engineering.Method: Built on agyn platform, creates specialized agents for coordination, research, implementation, and review roles. Uses isolated sandboxes, structured communication, and follows defined development methodology (analysis, task specification, PR creation, iterative review).
Result: Achieves 72.2% resolution rate on SWE-bench 500, outperforming single-agent baselines using comparable language models. Designed for real production use, not tuned for SWE-bench.
Conclusion: Replicating team structure, methodology, and communication is powerful for autonomous software engineering. Future progress may depend as much on organizational design and agent infrastructure as on model improvements.
Abstract: Large language models have demonstrated strong capabilities in individual software engineering tasks, yet most autonomous systems still treat issue resolution as a monolithic or pipeline-based process. In contrast, real-world software development is organized as a collaborative activity carried out by teams following shared methodologies, with clear role separation, communication, and review. In this work, we present a fully automated multi-agent system that explicitly models software engineering as an organizational process, replicating the structure of an engineering team. Built on top of agyn, an open-source platform for configuring agent teams, our system assigns specialized agents to roles such as coordination, research, implementation, and review, provides them with isolated sandboxes for experimentation, and enables structured communication. The system follows a defined development methodology for working on issues, including analysis, task specification, pull request creation, and iterative review, and operates without any human intervention. Importantly, the system was designed for real production use and was not tuned for SWE-bench. When evaluated post hoc on SWE-bench 500, it resolves 72.2% of tasks, outperforming single-agent baselines using comparable language models. Our results suggest that replicating team structure, methodology, and communication is a powerful paradigm for autonomous software engineering, and that future progress may depend as much on organizational design and agent infrastructure as on model improvements.
[672] ProjDevBench: Benchmarking AI Coding Agents on End-to-End Project Development
Pengrui Lu, Shiqi Zhang, Yunzhong Hou, Lyumanshan Ye, Chaoyi Huang, Zixi Chen, Ji Zeng, Hantao Jiang, Pengfei Liu, Yiwei Wang, Ming-Hsuan Yang
Main category: cs.AI
TL;DR: ProjDevBench: An end-to-end benchmark for evaluating coding agents on complete project development from requirements to functional repositories, using OJ testing and LLM-assisted code review across 20 programming problems.
Details
Motivation: Existing evaluations for coding agents focus only on issue-level bug fixing and lag behind end-to-end development capabilities, creating a need for comprehensive benchmarks that assess complete project development from requirements to functional codebases.Method: Introduces ProjDevBench with 20 programming problems across 8 categories, combining Online Judge testing with LLM-assisted code review to evaluate agents on system architecture design, functional correctness, and iterative solution refinement.
Result: Overall acceptance rate of 27.38% across six coding agents; agents handle basic functionality and data structures but struggle with complex system design, time complexity optimization, and resource management.
Conclusion: ProjDevBench provides a comprehensive end-to-end evaluation framework for coding agents, revealing current limitations in complex system design and optimization while offering a benchmark for future development.
Abstract: Recent coding agents can generate complete codebases from simple prompts, yet existing evaluations focus on issue-level bug fixing and lag behind end-to-end development. We introduce ProjDevBench, an end-to-end benchmark that provides project requirements to coding agents and evaluates the resulting repositories. Combining Online Judge (OJ) testing with LLM-assisted code review, the benchmark evaluates agents on (1) system architecture design, (2) functional correctness, and (3) iterative solution refinement. We curate 20 programming problems across 8 categories, covering both concept-oriented tasks and real-world application scenarios, and evaluate six coding agents built on different LLM backends. Our evaluation reports an overall acceptance rate of 27.38%: agents handle basic functionality and data structures but struggle with complex system design, time complexity optimization, and resource management. Our benchmark is available at https://github.com/zsworld6/projdevbench.
[673] FlowSteer: Interactive Agentic Workflow Orchestration via End-to-End Reinforcement Learning
Mingda Zhang, Haoran Luo, Tiesunlong Shen, Qika Lin, Xiaoying Tang, Rui Mao, Erik Cambria
Main category: cs.AI
TL;DR: FlowSteer: An RL framework for automated workflow orchestration using a policy model and canvas environment with plug-and-play operator/LLM support
Details
Motivation: Existing workflow orchestration faces challenges: high manual cost, reliance on specific operators/LLMs, and sparse reward signals. Need for automated, flexible workflow generation.Method: End-to-end RL framework with lightweight policy model as agent and executable canvas environment. Multi-turn interaction where policy analyzes states and selects editing actions, canvas executes operators and returns feedback. Supports plug-and-play operator libraries and interchangeable LLM backends. Uses Canvas Workflow Relative Policy Optimization (CWRPO) with diversity-constrained rewards and conditional release.
Result: Experimental results on twelve datasets show FlowSteer significantly outperforms baselines across various tasks.
Conclusion: FlowSteer provides an effective automated workflow orchestration solution that addresses key challenges of manual cost, operator/LLM dependency, and sparse rewards.
Abstract: In recent years, a variety of powerful agentic workflows have been applied to solve a wide range of human problems. However, existing workflow orchestration still faces key challenges, including high manual cost, reliance on specific operators/large language models (LLMs), and sparse reward signals. To address these challenges, we propose FlowSteer, an end-to-end reinforcement learning framework that takes a lightweight policy model as the agent and an executable canvas environment, automating workflow orchestration through multi-turn interaction. In this process, the policy model analyzes execution states and selects editing actions, while the canvas executes operators and returns feedback for iterative refinement. Moreover, FlowSteer provides a plug-and-play framework that supports diverse operator libraries and interchangeable LLM backends. To effectively train this interaction paradigm, we propose Canvas Workflow Relative Policy Optimization (CWRPO), which introduces diversity-constrained rewards with conditional release to stabilize learning and suppress shortcut behaviors. Experimental results on twelve datasets show that FlowSteer significantly outperforms baselines across various tasks.
[674] MACD: Model-Aware Contrastive Decoding via Counterfactual Data
Qixin Xiao
Main category: cs.AI
TL;DR: MACD is a new inference method that reduces hallucinations in Video-LLMs by using model-guided counterfactual data construction combined with contrastive decoding, focusing on object-level modifications based on the model’s own feedback.
Details
Motivation: Video-LLMs suffer from hallucinations when visual evidence is weak, ambiguous, or biased. Existing methods like contrastive decoding use random perturbations that don't align well with model weaknesses or control visual cues driving hallucinations.Method: MACD uses the Video-LLM’s own feedback to identify object regions most responsible for hallucinations, generates targeted counterfactual inputs at the object level (rather than arbitrary frame/temporal modifications), and integrates these model-aware counterfactual data into contrastive decoding to enforce evidence-grounded token selection.
Result: Experiments on EventHallusion, MVBench, Perception-test and Video-MME show MACD consistently reduces hallucination while maintaining or improving task accuracy across diverse Video-LLMs (Qwen and InternVL families). The method is especially effective for challenging scenarios involving small, occluded, or co-occurring objects.
Conclusion: MACD provides an effective inference strategy for reducing hallucinations in Video-LLMs by combining model-guided counterfactual construction with decoding, offering targeted improvements over existing methods.
Abstract: Video language models (Video-LLMs) are prone to hallucinations, often generating plausible but ungrounded content when visual evidence is weak, ambiguous, or biased. Existing decoding methods, such as contrastive decoding (CD), rely on random perturbations to construct contrastive data for mitigating hallucination patterns. However, such a way is hard to control the visual cues that drive hallucination or well align with model weaknesses. We propose Model-aware Counterfactual Data based Contrastive Decoding (MACD), a new inference strategy that combines model-guided counterfactual construction with decoding. Our approach uses the Video-LLM’s own feedback to identify object regions most responsible for hallucination, generating targeted counterfactual inputs at the object level rather than arbitrary frame or temporal modifications. These model-aware counterfactual data is then integrated into CD to enforce evidence-grounded token selection during decoding. Experiments on EventHallusion, MVBench, Perception-test and Video-MME show that MACD consistently reduces hallucination while maintaining or improving task accuracy across diverse Video-LLMs, including Qwen and InternVL families. The method is especially effective in challenging scenarios involving small, occluded, or co-occurring objects. Our code and data will be publicly released.
[675] Beyond Quantity: Trajectory Diversity Scaling for Code Agents
Guhong Chen, Chenghao Sun, Cheng Fu, Qiyao Wang, Zhihong Huang, Chaopeng Wei, Guangxu Chen, Feiteng Fang, Ahmadreza Argha, Bing Zhao, Xander Xu, Qi Han, Hamid Alinejad-Rokny, Qiang Qu, Binhua Li, Shiwen Ni, Min Yang, Hu Wei, Yongbin Li
Main category: cs.AI
TL;DR: TDScaling is a trajectory diversity scaling framework for code LLM agents that improves performance through diverse data synthesis rather than raw volume scaling, addressing limitations of current synthetic data approaches.
Details
Motivation: Current code LLM agents face limitations from low-quality synthetic data and diminishing returns from quantity scaling, with early bottlenecks that underutilize trajectory data. There's a need for better performance-cost trade-offs in agent training.Method: Proposes TDScaling framework with four innovations: 1) Business Cluster mechanism for real-service logical dependencies, 2) blueprint-driven multi-agent paradigm for trajectory coherence, 3) adaptive evolution mechanism using Domain Entropy, Reasoning Mode Entropy, and Cumulative Action Complexity to prevent mode collapse, and 4) sandboxed code tool to mitigate catastrophic forgetting.
Result: Experiments on tool-use benchmarks (BFCL, tau^2-Bench) and code agent tasks (RebenchT, CodeCI, BIRD) show TDScaling improves both tool-use generalization and inherent coding proficiency, achieving win-win outcomes.
Conclusion: Diversity scaling outperforms quantity scaling for code agent training, offering better performance-cost trade-offs. The framework enables improved generalization while maintaining coding capabilities.
Abstract: As code large language models (LLMs) evolve into tool-interactive agents via the Model Context Protocol (MCP), their generalization is increasingly limited by low-quality synthetic data and the diminishing returns of quantity scaling. Moreover, quantity-centric scaling exhibits an early bottleneck that underutilizes trajectory data. We propose TDScaling, a Trajectory Diversity Scaling-based data synthesis framework for code agents that scales performance through diversity rather than raw volume. Under a fixed training budget, increasing trajectory diversity yields larger gains than adding more trajectories, improving the performance-cost trade-off for agent training. TDScaling integrates four innovations: (1) a Business Cluster mechanism that captures real-service logical dependencies; (2) a blueprint-driven multi-agent paradigm that enforces trajectory coherence; (3) an adaptive evolution mechanism that steers synthesis toward long-tail scenarios using Domain Entropy, Reasoning Mode Entropy, and Cumulative Action Complexity to prevent mode collapse; and (4) a sandboxed code tool that mitigates catastrophic forgetting of intrinsic coding capabilities. Experiments on general tool-use benchmarks (BFCL, tau^2-Bench) and code agent tasks (RebenchT, CodeCI, BIRD) demonstrate a win-win outcome: TDScaling improves both tool-use generalization and inherent coding proficiency. We plan to release the full codebase and the synthesized dataset (including 30,000+ tool clusters) upon publication.
[676] Reactive Knowledge Representation and Asynchronous Reasoning
Simon Kohaut, Benedict Flade, Julian Eggert, Kristian Kersting, Devendra Singh Dhami
Main category: cs.AI
TL;DR: Resin (Reactive Signal Inference) is a probabilistic programming language combining probabilistic logic with reactive programming, using Reactive Circuits for efficient exact inference in dynamic environments by adapting computations based on input signal volatility.
Details
Motivation: Exact inference in complex probabilistic models is computationally expensive, especially for autonomous agents in dynamic environments requiring frequent real-time belief updates. Existing methods inefficiently re-evaluate entire models upon changes, failing to exploit heterogeneous update rates in real-world information streams.Method: Introduces Resin (Reactive Signal Inference), a probabilistic programming language merging probabilistic logic with reactive programming. Proposes Reactive Circuits (RCs) as a meta-structure over Algebraic Circuits and asynchronous data streams - time-dynamic Directed Acyclic Graphs that autonomously adapt based on input signal volatility.
Result: In high-fidelity drone swarm simulations, the approach achieves several orders of magnitude speedup over frequency-agnostic inference. RCs’ structural adaptations successfully capture environmental dynamics, significantly reducing latency and facilitating reactive real-time reasoning.
Conclusion: By partitioning computations based on estimated Frequency of Change in asynchronous inputs, large inference tasks can be decomposed into memoized sub-problems, ensuring only affected model components are re-evaluated, drastically reducing redundant computation in streaming contexts.
Abstract: Exact inference in complex probabilistic models often incurs prohibitive computational costs. This challenge is particularly acute for autonomous agents in dynamic environments that require frequent, real-time belief updates. Existing methods are often inefficient for ongoing reasoning, as they re-evaluate the entire model upon any change, failing to exploit that real-world information streams have heterogeneous update rates. To address this, we approach the problem from a reactive, asynchronous, probabilistic reasoning perspective. We first introduce Resin (Reactive Signal Inference), a probabilistic programming language that merges probabilistic logic with reactive programming. Furthermore, to provide efficient and exact semantics for Resin, we propose Reactive Circuits (RCs). Formulated as a meta-structure over Algebraic Circuits and asynchronous data streams, RCs are time-dynamic Directed Acyclic Graphs that autonomously adapt themselves based on the volatility of input signals. In high-fidelity drone swarm simulations, our approach achieves several orders of magnitude of speedup over frequency-agnostic inference. We demonstrate that RCs’ structural adaptations successfully capture environmental dynamics, significantly reducing latency and facilitating reactive real-time reasoning. By partitioning computations based on the estimated Frequency of Change in the asynchronous inputs, large inference tasks can be decomposed into individually memoized sub-problems. This ensures that only the specific components of a model affected by new information are re-evaluated, drastically reducing redundant computation in streaming contexts.
[677] TKG-Thinker: Towards Dynamic Reasoning over Temporal Knowledge Graphs via Agentic Reinforcement Learning
Zihao Jiang, Miao Peng, Zhenyan Shan, Wenjie Xu, Ben Liu, Gong Chen, Ziqi Gao, Min Peng
Main category: cs.AI
TL;DR: TKG-Thinker is an agent-based approach for temporal knowledge graph question answering that uses autonomous planning and adaptive retrieval with dual-training (SFT + RL) to improve LLM reasoning over temporal knowledge graphs.
Details
Motivation: Current LLM prompting strategies for TKGQA suffer from reasoning hallucinations under complex temporal constraints and lack optimization through dynamic interaction with temporal knowledge graphs, limiting model autonomy and generalization.Method: Proposes TKG-Thinker agent with autonomous planning and adaptive retrieval capabilities. Uses dual-training: 1) Supervised Fine-Tuning with chain-of-thought data for core planning, 2) Reinforcement Learning with multi-dimensional rewards to refine reasoning policies under temporal constraints.
Result: Achieves state-of-the-art performance on benchmark datasets with three open-source LLMs and exhibits strong generalization across complex TKGQA settings.
Conclusion: TKG-Thinker effectively addresses limitations of current prompting strategies by enabling dynamic multi-turn interactions with TKGs through autonomous planning and adaptive retrieval, demonstrating superior performance and generalization.
Abstract: Temporal knowledge graph question answering (TKGQA) aims to answer time-sensitive questions by leveraging temporal knowledge bases. While Large Language Models (LLMs) demonstrate significant potential in TKGQA, current prompting strategies constrain their efficacy in two primary ways. First, they are prone to reasoning hallucinations under complex temporal constraints. Second, static prompting limits model autonomy and generalization, as it lack optimization through dynamic interaction with temporal knowledge graphs (TKGs) environments. To address these limitations, we propose \textbf{TKG-Thinker}, a novel agent equipped with autonomous planning and adaptive retrieval capabilities for reasoning over TKGs. Specifically, TKG-Thinker performs in-depth temporal reasoning through dynamic multi-turn interactions with TKGs via a dual-training strategy. We first apply Supervised Fine-Tuning (SFT) with chain of thought data to instill core planning capabilities, followed by a Reinforcement Learning (RL) stage that leverages multi-dimensional rewards to refine reasoning policies under intricate temporal constraints. Experimental results on benchmark datasets with three open-source LLMs show that TKG-Thinker achieves state-of-the-art performance and exhibits strong generalization across complex TKGQA settings.
[678] From Features to Actions: Explainability in Traditional and Agentic AI Systems
Sindhuja Chaduvula, Jessee Ho, Kina Kim, Aravind Narayanan, Mahshid Alinoori, Muskan Garg, Dhanesh Ramachandram, Shaina Raza
Main category: cs.AI
TL;DR: The paper compares static attribution-based explanations with trace-based diagnostics for agentic AI systems, showing that attribution methods work well for static predictions but fail to diagnose execution-level failures in multi-step agentic trajectories.
Details
Motivation: Traditional explainable AI focuses on interpreting individual model predictions, but recent advances in LLMs enable agentic AI systems with multi-step trajectories. There's a gap in understanding how explanation approaches designed for static predictions translate to agentic settings where behavior emerges over time.Method: The authors compare attribution-based explanations (used in static classification) with trace-based diagnostics (used in agentic benchmarks). They empirically evaluate both approaches using static classification tasks and agentic benchmarks (TAU-bench Airline and AssistantBench).
Result: Attribution methods achieve stable feature rankings in static settings (Spearman ρ=0.86) but cannot reliably diagnose execution-level failures in agentic trajectories. Trace-grounded rubric evaluation consistently localizes behavior breakdowns and reveals that state tracking inconsistency is 2.7× more prevalent in failed runs and reduces success probability by 49%.
Conclusion: The findings motivate a shift towards trajectory-level explainability for agentic systems when evaluating and diagnosing autonomous AI behavior, moving beyond static attribution methods to trace-based diagnostics.
Abstract: Over the last decade, explainable AI has primarily focused on interpreting individual model predictions, producing post-hoc explanations that relate inputs to outputs under a fixed decision structure. Recent advances in large language models (LLMs) have enabled agentic AI systems whose behaviour unfolds over multi-step trajectories. In these settings, success and failure are determined by sequences of decisions rather than a single output. While useful, it remains unclear how explanation approaches designed for static predictions translate to agentic settings where behaviour emerges over time. In this work, we bridge the gap between static and agentic explainability by comparing attribution-based explanations with trace-based diagnostics across both settings. To make this distinction explicit, we empirically compare attribution-based explanations used in static classification tasks with trace-based diagnostics used in agentic benchmarks (TAU-bench Airline and AssistantBench). Our results show that while attribution methods achieve stable feature rankings in static settings (Spearman $ρ= 0.86$), they cannot be applied reliably to diagnose execution-level failures in agentic trajectories. In contrast, trace-grounded rubric evaluation for agentic settings consistently localizes behaviour breakdowns and reveals that state tracking inconsistency is 2.7$\times$ more prevalent in failed runs and reduces success probability by 49%. These findings motivate a shift towards trajectory-level explainability for agentic systems when evaluating and diagnosing autonomous AI behaviour. Resources: https://github.com/VectorInstitute/unified-xai-evaluation-framework https://vectorinstitute.github.io/unified-xai-evaluation-framework
[679] AIRS-Bench: a Suite of Tasks for Frontier AI Research Science Agents
Alisia Lupidi, Bhavul Gauri, Thomas Simon Foster, Bassel Al Omari, Despoina Magka, Alberto Pepe, Alexis Audran-Reiss, Muna Aghamelu, Nicolas Baldwin, Lucia Cipolina-Kun, Jean-Christophe Gagnon-Audet, Chee Hau Leow, Sandra Lefdal, Hossam Mossalam, Abhinav Moudgil, Saba Nazir, Emanuel Tewolde, Isabel Urrego, Jordi Armengol Estape, Amar Budhiraja, Gaurav Chaurasia, Abhishek Charnalia, Derek Dunfield, Karen Hambardzumyan, Daniel Izcovich, Martin Josifoski, Ishita Mediratta, Kelvin Niu, Parth Pathak, Michael Shvartsman, Edan Toledo, Anton Protopopov, Roberta Raileanu, Alexander Miller, Tatiana Shavrina, Jakob Foerster, Yoram Bachrach
Main category: cs.AI
TL;DR: AIRS-Bench is a benchmark suite of 20 ML research tasks that evaluates LLM agents’ capabilities across the full scientific research lifecycle without providing baseline code, showing agents exceed human SOTA in 4 tasks but fail in 16 others.
Details
Motivation: To accelerate progress in LLM agents for scientific research by providing a comprehensive benchmark that assesses agentic capabilities across the entire research lifecycle, from idea generation to iterative refinement.Method: Created AIRS-Bench with 20 tasks sourced from state-of-the-art ML papers across diverse domains (language modeling, mathematics, bioinformatics, time series forecasting). Tasks are designed without baseline code to test true agentic capabilities. Established baselines using frontier models with sequential and parallel scaffolds.
Result: Agents exceeded human SOTA in 4 out of 20 tasks but failed to match human performance in 16 tasks. Even when agents surpassed human benchmarks, they didn’t reach the theoretical performance ceiling, indicating substantial room for improvement.
Conclusion: AIRS-Bench is far from saturated and offers significant opportunities for advancing autonomous scientific research. The benchmark is open-sourced to catalyze further development in this area.
Abstract: LLM agents hold significant promise for advancing scientific research. To accelerate this progress, we introduce AIRS-Bench (the AI Research Science Benchmark), a suite of 20 tasks sourced from state-of-the-art machine learning papers. These tasks span diverse domains, including language modeling, mathematics, bioinformatics, and time series forecasting. AIRS-Bench tasks assess agentic capabilities over the full research lifecycle – including idea generation, experiment analysis and iterative refinement – without providing baseline code. The AIRS-Bench task format is versatile, enabling easy integration of new tasks and rigorous comparison across different agentic frameworks. We establish baselines using frontier models paired with both sequential and parallel scaffolds. Our results show that agents exceed human SOTA in four tasks but fail to match it in sixteen others. Even when agents surpass human benchmarks, they do not reach the theoretical performance ceiling for the underlying tasks. These findings indicate that AIRS-Bench is far from saturated and offers substantial room for improvement. We open-source the AIRS-Bench task definitions and evaluation code to catalyze further development in autonomous scientific research.
cs.SD
[680] MENASpeechBank: A Reference Voice Bank with Persona-Conditioned Multi-Turn Conversations for AudioLLMs
Zien Sheikh Ali, Hunzalah Hassan Bhatti, Rabindra Nath Nandi, Shammur Absar Chowdhury, Firoj Alam
Main category: cs.SD
TL;DR: MENASpeechBank: A speech dataset with 18K utterances from 124 speakers across MENA countries, plus a pipeline to generate 417K synthetic persona-grounded conversations for AudioLLM training.
Details
Motivation: AudioLLMs need diverse, conversational, instruction-aligned speech-text data, especially for persona-grounded interactions and dialectal coverage. Real multi-speaker recordings are costly and slow to collect, creating a bottleneck for progress.Method: 1) Create MENASpeechBank with 18K high-quality utterances from 124 speakers across MENA countries; 2) Develop controllable synthetic data pipeline: construct persona profiles with World Values Survey attributes, define 5K conversational scenarios, match personas to scenarios via semantic similarity, generate 417K role-play conversations with LLM, synthesize user turns by conditioning on reference speaker audio.
Result: Created MENASpeechBank dataset and generated 417K synthetic conversations. Evaluated both synthetic and human-recorded conversations with detailed analysis. Will release both resources publicly.
Conclusion: The paper addresses the data bottleneck for AudioLLMs by providing a high-quality speech dataset and scalable synthetic data generation pipeline, enabling better persona-grounded and dialectally diverse audio language models.
Abstract: Audio large language models (AudioLLMs) enable instruction-following over speech and general audio, but progress is increasingly limited by the lack of diverse, conversational, instruction-aligned speech-text data. This bottleneck is especially acute for persona-grounded interactions and dialectal coverage, where collecting and releasing real multi-speaker recordings is costly and slow. We introduce MENASpeechBank, a reference speech bank comprising about 18K high-quality utterances from 124 speakers spanning multiple MENA countries, covering English, Modern Standard Arabic (MSA), and regional Arabic varieties. Building on this resource, we develop a controllable synthetic data pipeline that: (i) constructs persona profiles enriched with World Values Survey-inspired attributes, (ii) defines a taxonomy of about 5K conversational scenarios, (iii) matches personas to scenarios via semantic similarity, (iv) generates about 417K role-play conversations with an LLM where the user speaks as the persona and the assistant behaves as a helpful agent, and (v) synthesizes the user turns by conditioning on reference speaker audio to preserve speaker identity and diversity. We evaluate both synthetic and human-recorded conversations and provide detailed analysis. We will release MENASpeechBank and the generated conversations publicly for the community.
[681] CALM: Class-Conditional Sparse Attention Vectors for Large Audio-Language Models
Videet Mehta, Liming Wang, Hilde Kuehne, Rogerio Feris, James R. Glass, M. Jehanzeb Mirza
Main category: cs.SD
TL;DR: Class-conditional sparse attention vectors improve few-shot audio classification by learning category-specific importance weights for attention heads in large audio-language models.
Details
Motivation: While large audio-language models have strong zero-shot capabilities, they underperform specialized models on discriminative tasks like classification. Existing methods use uniform weighting of attention heads, ignoring that different heads may specialize in different semantic categories.Method: Proposes class-conditional sparse attention vectors that learn class-dependent importance weights over attention heads, allowing heads to specialize in distinct categories and contribute proportionally to their reliability in ensemble predictions.
Result: Outperforms state-of-the-art uniform voting-based approaches by up to 14.52% for audio classification, 1.53% for audio-visual classification, and 8.35% for spoofing detection on few-shot benchmarks.
Conclusion: Learning class-dependent importance weights for attention heads significantly improves few-shot classification performance in large audio-language models by better leveraging head specialization across semantic categories.
Abstract: Large audio-language models (LALMs) exhibit strong zero-shot capabilities in multiple downstream tasks, such as audio question answering (AQA) and abstract reasoning; however, these models still lag behind specialized models for certain discriminative tasks (e.g., audio classification). Recent studies show that sparse subsets of attention heads within an LALM can serve as strong discriminative feature extractors for downstream tasks such as classification via simple voting schemes. However, these methods assign uniform weights to all selected heads, implicitly assuming that each head contributes equally across all semantic categories. In this work, we propose Class-Conditional Sparse Attention Vectors for Large Audio-Language Models, a few-shot classification method that learns class-dependent importance weights over attention heads. This formulation allows individual heads to specialize in distinct semantic categories and to contribute to ensemble predictions proportionally to their estimated reliability. Experiments on multiple few-shot audio and audiovisual classification benchmarks and tasks demonstrate that our method consistently outperforms state-of-the-art uniform voting-based approaches by up to 14.52%, 1.53%, 8.35% absolute gains for audio classification, audio-visual classification, and spoofing detection respectively.
[682] SNC: A Stem-Native Codec for Efficient Lossless Audio Storage with Adaptive Playback Capabilities
Shaad Sufi
Main category: cs.SD
TL;DR: SNC is a novel audio format that stores music as separately encoded stems plus a residual, achieving 38% size reduction over FLAC while enabling adaptive playback, spatial audio, and user remixing.
Details
Motivation: Current audio formats force a trade-off between file size and functionality: lossless formats preserve quality but lack adaptability, while lossy formats reduce size at the cost of fidelity and offer no stem-level access for advanced features.Method: Stem-Native Codec (SNC) stores music as independently encoded stems plus a low-energy mastering residual, exploiting the lower information entropy of separated stems compared to mixed audio to achieve compression while maintaining quality.
Result: SNC achieves 38.2% file size reduction versus FLAC (7.76 MB vs. 12.55 MB for a 2:18 test track) while maintaining perceptual transparency (STOI = 0.996). Enables context-aware adaptive playback, spatial audio rendering, and user-controlled remixing.
Conclusion: The stems-plus-residual architecture successfully decouples compression efficiency from feature richness, offering a practical path toward next-generation audio distribution systems with both high quality and advanced functionality.
Abstract: Current audio formats present a fundamental trade-off between file size and functionality: lossless formats like FLAC preserve quality but lack adaptability, while lossy formats reduce size at the cost of fidelity and offer no stem-level access.We introduce the Stem-Native Codec (SNC), a novel audio container format that stores music as independently encoded stems plus a low-energy mastering residual. By exploiting the lower information entropy of separated stems compared to mixed audio, SNC achieves a 38.2% file size reduction versus FLAC (7.76 MB vs. 12.55 MB for a 2:18 test track) while maintaining perceptual transparency (STOI = 0.996). Unlike existing formats, SNC enables context-aware adaptive playback, spatial audio rendering, and user-controlled remixing without requiring additional storage. Our experimental validation demonstrates that the stems-plus residual architecture successfully decouples the conflicting requirements of compression efficiency and feature richness, offering a practical path toward next-generation audio distribution systems.
[683] Massive Sound Embedding Benchmark (MSEB)
Georg Heigold, Ehsan Variani, Tom Bagby, Cyril Allauzen, Ji Ma, Shankar Kumar, Michael Riley
Main category: cs.SD
TL;DR: MSEB is a comprehensive benchmark framework for evaluating audio embeddings across multiple auditory tasks including transcription, classification, retrieval, reasoning, segmentation, clustering, reranking, and reconstruction.
Details
Motivation: Audio is essential for multimodal perception in intelligent systems, but there's a need for standardized evaluation of audio embeddings across diverse auditory capabilities to accelerate progress in machine auditory intelligence.Method: Developed the Massive Sound Embedding Benchmark (MSEB) - an extensible framework with 8 core tasks, diverse datasets including the new Simple Voice Questions (SVQ) dataset, and standardized evaluation protocols for audio embeddings.
Result: Established clear performance headrooms showing significant opportunity for improvement in real-world multimodal experiences where audio is a core signal. The benchmark provides baseline evaluations and identifies gaps in current audio embedding capabilities.
Conclusion: MSEB serves as a comprehensive tool for the research community to assess audio components of multimodal systems and drive progress toward robust machine auditory intelligence through standardized evaluation.
Abstract: Audio is a critical component of multimodal perception, and any truly intelligent system must demonstrate a wide range of auditory capabilities. These capabilities include transcription, classification, retrieval, reasoning, segmentation, clustering, reranking, and reconstruction. Fundamentally, each task involves transforming a raw audio signal into a meaningful ’embedding’ - be it a single vector, a sequence of continuous or discrete representations, or another structured form - which then serves as the basis for generating the task’s final response. To accelerate progress towards robust machine auditory intelligence, we present the Massive Sound Embedding Benchmark (MSEB): an extensible framework designed to evaluate the auditory components of any multimodal system. In its first release, MSEB offers a comprehensive suite of eight core tasks, with more planned for the future, supported by diverse datasets, including the new, large-scale Simple Voice Questions (SVQ) dataset. Our initial experiments establish clear performance headrooms, highlighting the significant opportunity to improve real-world multimodal experiences where audio is a core signal. We encourage the research community to use MSEB to assess their algorithms and contribute to its growth. The library is publicly hosted at github.
[684] Tutti: Expressive Multi-Singer Synthesis via Structure-Level Timbre Control and Vocal Texture Modeling
Jiatao Chen, Xing Tang, Xiaoyue Duan, Yutang Feng, Jinchao Zhang, Jie Zhou
Main category: cs.SD
TL;DR: Tutti is a unified framework for structured multi-singer generation that enables dynamic singer scheduling and captures complementary acoustic textures for realistic choral synthesis.
Details
Motivation: Existing singing voice synthesis systems are limited to global timbre control and cannot handle dynamic multi-singer arrangements or capture subtle vocal textures within a single song, which is essential for realistic choral generation.Method: Proposes Tutti framework with: 1) Structure-Aware Singer Prompt for flexible singer scheduling that evolves with musical structure, and 2) Complementary Texture Learning via Condition-Guided VAE to capture implicit acoustic textures like spatial reverberation and spectral fusion.
Result: Experiments show Tutti excels in precise multi-singer scheduling and significantly enhances acoustic realism of choral generation, offering a novel paradigm for complex multi-singer arrangement.
Conclusion: Tutti provides an effective solution for structured multi-singer generation, addressing limitations of existing systems and enabling more realistic choral synthesis with dynamic singer arrangements and rich acoustic textures.
Abstract: While existing Singing Voice Synthesis systems achieve high-fidelity solo performances, they are constrained by global timbre control, failing to address dynamic multi-singer arrangement and vocal texture within a single song. To address this, we propose Tutti, a unified framework designed for structured multi-singer generation. Specifically, we introduce a Structure-Aware Singer Prompt to enable flexible singer scheduling evolving with musical structure, and propose Complementary Texture Learning via Condition-Guided VAE to capture implicit acoustic textures (e.g., spatial reverberation and spectral fusion) that are complementary to explicit controls. Experiments demonstrate that Tutti excels in precise multi-singer scheduling and significantly enhances the acoustic realism of choral generation, offering a novel paradigm for complex multi-singer arrangement. Audio samples are available at https://annoauth123-ctrl.github.io/Tutii_Demo/.
[685] Global Rotation Equivariant Phase Modeling for Speech Enhancement with Deep Magnitude-Phase Interaction
Chengzhong Wang, Andong Li, Dingding Yao, Junfeng Li
Main category: cs.SD
TL;DR: A manifold-aware magnitude-phase dual-stream framework for speech enhancement that models phase’s circular topology using Global Rotation Equivariance, achieving state-of-the-art performance across multiple SE tasks.
Details
Motivation: Conventional speech enhancement networks operate in flat Euclidean feature spaces, which fail to properly model the circular topology of phase information, limiting phase modeling effectiveness.Method: Proposes a dual-stream framework with Global Rotation Equivariance (GRE) for phase stream, Magnitude-Phase Interactive Convolutional Module (MPICM) for information exchange, and Hybrid-Attention Dual-FFN (HADF) bottleneck for unified feature fusion while preserving GRE.
Result: Achieves over 20% reduction in Phase Distance for phase retrieval, improves PESQ by more than 0.1 in zero-shot cross-corpus denoising, and shows superiority in universal SE tasks with mixed distortions.
Conclusion: The manifold-aware approach effectively models phase’s circular nature, leading to significant improvements in speech enhancement performance across diverse tasks.
Abstract: While deep learning has advanced speech enhancement (SE), effective phase modeling remains challenging, as conventional networks typically operate within a flat Euclidean feature space, which is not easy to model the underlying circular topology of the phase. To address this, we propose a manifold-aware magnitude-phase dual-stream framework that aligns the phase stream with its intrinsic circular geometry by enforcing Global Rotation Equivariance (GRE) characteristic. Specifically, we introduce a Magnitude-Phase Interactive Convolutional Module (MPICM) for modulus-based information exchange and a Hybrid-Attention Dual-FFN (HADF) bottleneck for unified feature fusion, both of which are designed to preserve GRE in the phase stream. Comprehensive evaluations are conducted across phase retrieval, denoising, dereverberation, and bandwidth extension tasks to validate the superiority of the proposed method over multiple advanced baselines. Notably, the proposed architecture reduces Phase Distance by over 20% in the phase retrieval task and improves PESQ by more than 0.1 in zero-shot cross-corpus denoising evaluations. The overall superiority is also established in universal SE tasks involving mixed distortions. Qualitative analysis further reveals that the learned phase features exhibit distinct periodic patterns, which are consistent with the intrinsic circular nature of the phase. The source code is available at https://github.com/wangchengzhong/RENet.
[686] Prototype-Based Disentanglement for Controllable Dysarthric Speech Synthesis
Haoshen Wang, Xueli Zhong, Bingbing Lin, Jia Huang, Xingduo Pan, Shengxiang Liang, Nizhuan Wang, Wai Ting Siok
Main category: cs.SD
TL;DR: ProtoDisent-TTS: A prototype-based disentanglement TTS framework that separates speaker timbre from dysarthric articulation using pathology prototypes and dual-classifier training for controllable speech transformation.
Details
Motivation: Dysarthric speech has high variability and limited labeled data, making ASR and assistive technologies challenging. Existing methods often entangle speaker identity with pathological articulation, limiting controllability and robustness.Method: Built on pre-trained TTS backbone, uses pathology prototype codebook for interpretable representations of healthy/dysarthric patterns, dual-classifier objective with gradient reversal layer to enforce speaker embedding invariance to pathological attributes.
Result: Experiments on TORGO dataset show bidirectional transformation between healthy and dysarthric speech, consistent ASR performance gains, and robust speaker-aware speech reconstruction.
Conclusion: The framework effectively disentangles speaker identity from pathological articulation, enabling controllable speech transformation and improved assistive technologies for dysarthric speech.
Abstract: Dysarthric speech exhibits high variability and limited labeled data, posing major challenges for both automatic speech recognition (ASR) and assistive speech technologies. Existing approaches rely on synthetic data augmentation or speech reconstruction, yet often entangle speaker identity with pathological articulation, limiting controllability and robustness. In this paper, we propose ProtoDisent-TTS, a prototype-based disentanglement TTS framework built on a pre-trained text-to-speech backbone that factorizes speaker timbre and dysarthric articulation within a unified latent space. A pathology prototype codebook provides interpretable and controllable representations of healthy and dysarthric speech patterns, while a dual-classifier objective with a gradient reversal layer enforces invariance of speaker embeddings to pathological attributes. Experiments on the TORGO dataset demonstrate that this design enables bidirectional transformation between healthy and dysarthric speech, leading to consistent ASR performance gains and robust, speaker-aware speech reconstruction.
[687] No Word Left Behind: Mitigating Prefix Bias in Open-Vocabulary Keyword Spotting
Yi Liu, Chuan-Che, Huang, Xiao Quan
Main category: cs.SD
TL;DR: The paper introduces a Partial Overlap Benchmark (POB) to address prefix bias in open-vocabulary keyword spotting and proposes Equal-weighting Position Scoring (EPS) to improve performance on ambiguous prefix-shared commands.
Details
Motivation: Existing open-vocabulary keyword spotting solutions suffer from prefix bias, causing false triggers when enrollment-query pairs share prefixes (e.g., "turn the volume up" vs. "turn the volume down"). This bias stems from training data limitations and position-biased cross-modal scoring.Method: 1) Introduces Partial Overlap Benchmark (POB) with two datasets (POB-Spark and POB-LibriPhrase) containing mismatched audio-text pairs with shared prefixes. 2) Proposes Equal-weighting Position Scoring (EPS), a lightweight decision layer that addresses position bias in cross-modal scoring.
Result: EPS alone reduces EER on POB-Spark from 64.4% to 29.3% and improves POB-LP accuracy from 87.6% to 96.8%, while maintaining performance on LibriPhrase and Google Speech Commands. With POB data added in training, achieves best POB benchmark results with least degradation on prior metrics.
Conclusion: The work successfully addresses prefix bias in open-vocabulary keyword spotting through benchmark creation and algorithmic improvements, though trade-offs with single-word command datasets remain a challenge for future work.
Abstract: Open-vocabulary keyword spotting (OV-KWS) enables personalized device control via arbitrary voice commands. Recently, researchers have explored using audio-text joint embeddings, allowing users to enroll phrases with text, and proposed techniques to disambiguate similar utterances. We find that existing OV-KWS solutions often overly bias the beginning phonemes of an enrollment, causing false triggers when negative enrollment-query-pairs share a prefix (turn the volume up'' vs. turn the volume down’’). We trace this to two factors: training data bias and position-biased cross-modal scoring. To address these limitations, we introduce the Partial Overlap Benchmark (POB) with two datasets, POB-Spark and POB-LibriPhrase (POB-LP), containing mismatched audio-text pairs with shared prefixes, and propose Equal-weighting Position Scoring (EPS), a lightweight decision layer. Using EPS alone reduces EER on POB-Spark from 64.4% to 29.3% and improves POB-LP accuracy from 87.6% to 96.8%, while maintaining performance on LibriPhrase and Google Speech Commands (GSC). With POB data added in training, our work achieves the best POB benchmark results while incurring the least amount of degradation on prior metrics among baselines. This degradation is most pronounced in GSC, which contains only one-word commands. We surface mitigating this trade-off as future work.
[688] Beyond Transcripts: A Renewed Perspective on Audio Chaptering
Fabian Retkowski, Maike Züfle, Thai Binh Nguyen, Jan Niehues, Alexander Waibel
Main category: cs.SD
TL;DR: AudioSeg, a novel audio-only architecture for audio chaptering, outperforms text-based methods and multimodal LLMs on long-form audio segmentation tasks, with pauses being the most important acoustic feature.
Details
Motivation: Audio chaptering is important for navigating podcasts, lectures, and videos, but current research is limited to text-based approaches, leaving gaps in leveraging audio information, handling ASR errors, and transcript-free evaluation.Method: Three contributions: (1) systematic comparison of text-based models with acoustic features, novel audio-only architecture (AudioSeg), and multimodal LLMs; (2) empirical analysis of factors affecting performance; (3) formalized evaluation protocols for transcript-dependent vs transcript-invariant evaluation.
Result: AudioSeg substantially outperforms text-based approaches, pauses provide the largest acoustic gains, and MLLMs remain limited by context length and weak instruction following but show promise on shorter audio.
Conclusion: Audio-only approaches like AudioSeg are superior for audio chaptering, acoustic features (especially pauses) are crucial, and MLLMs need improvements in context length and instruction following to be effective for long-form audio.
Abstract: Audio chaptering, the task of automatically segmenting long-form audio into coherent sections, is increasingly important for navigating podcasts, lectures, and videos. Despite its relevance, research remains limited and text-based, leaving key questions unresolved about leveraging audio information, handling ASR errors, and transcript-free evaluation. We address these gaps through three contributions: (1) a systematic comparison between text-based models with acoustic features, a novel audio-only architecture (AudioSeg) operating on learned audio representations, and multimodal LLMs; (2) empirical analysis of factors affecting performance, including transcript quality, acoustic features, duration, and speaker composition; and (3) formalized evaluation protocols contrasting transcript-dependent text-space protocols with transcript-invariant time-space protocols. Our experiments on YTSeg reveal that AudioSeg substantially outperforms text-based approaches, pauses provide the largest acoustic gains, and MLLMs remain limited by context length and weak instruction following, yet MLLMs are promising on shorter audio.
[689] Fed-PISA: Federated Voice Cloning via Personalized Identity-Style Adaptation
Qi Wang, Shituo Ma, Guoxin Yu, Hanyang Peng, Yue Yu
Main category: cs.SD
TL;DR: Fed-PISA is a federated learning approach for voice cloning that uses disentangled LoRA modules to reduce communication costs while preserving speaker identity and style through personalized aggregation.
Details
Motivation: Existing federated learning approaches for TTS voice cloning suffer from high communication costs and suppress stylistic heterogeneity, leading to insufficient personalization and privacy concerns.Method: Proposes Fed-PISA with: 1) Disentangled LoRA mechanism - private ID-LoRA for speaker timbre (kept locally) and lightweight style-LoRA for transmission; 2) Collaborative filtering-inspired aggregation to create custom models by learning from stylistically similar peers.
Result: Fed-PISA improves style expressivity, naturalness, and speaker similarity while outperforming standard federated baselines with minimal communication costs.
Conclusion: Fed-PISA provides an effective federated learning solution for personalized voice cloning that balances privacy, communication efficiency, and stylistic heterogeneity preservation.
Abstract: Voice cloning for Text-to-Speech (TTS) aims to generate expressive and personalized speech from text using limited data from a target speaker. Federated Learning (FL) offers a collaborative and privacy-preserving framework for this task, but existing approaches suffer from high communication costs and tend to suppress stylistic heterogeneity, resulting in insufficient personalization. To address these issues, we propose Fed-PISA, which stands for Federated Personalized Identity-Style Adaptation. To minimize communication costs, Fed-PISA introduces a disentangled Low-Rank Adaptation (LoRA) mechanism: the speaker’s timbre is retained locally through a private ID-LoRA, while only a lightweight style-LoRA is transmitted to the server, thereby minimizing parameter exchange. To harness heterogeneity, our aggregation method, inspired by collaborative filtering, is introduced to create custom models for each client by learning from stylistically similar peers. Experiments show that Fed-PISA improves style expressivity, naturalness, and speaker similarity, outperforming standard federated baselines with minimal communication costs.
[690] DegDiT: Controllable Audio Generation with Dynamic Event Graph Guided Diffusion Transformer
Yisu Liu, Chenxing Li, Wanqian Zhang, Wenfu Wang, Meng Yu, Ruibo Fu, Zheng Lin, Weiping Wang, Dong Yu
Main category: cs.SD
TL;DR: DegDiT: A dynamic event graph-guided diffusion transformer framework for open-vocabulary controllable audio generation with precise temporal control.
Details
Motivation: Existing text-to-audio generation methods face trade-offs between accurate temporal localization, open-vocabulary scalability, and practical efficiency. There's a need for better control over both content and temporal structure in generated audio.Method: Proposes DegDiT framework that encodes events as structured dynamic graphs with nodes representing semantic features, temporal attributes, and inter-event connections. Uses graph transformer to produce contextualized event embeddings for diffusion model guidance. Includes quality-balanced data selection pipeline and consensus preference optimization.
Result: Achieves state-of-the-art performance on AudioCondition, DESED, and AudioTime datasets across objective and subjective evaluation metrics.
Conclusion: DegDiT effectively addresses the trade-offs in controllable text-to-audio generation, enabling precise temporal control with open-vocabulary scalability and practical efficiency.
Abstract: Controllable text-to-audio generation aims to synthesize audio from textual descriptions while satisfying user-specified constraints, including event types, temporal sequences, and onset and offset timestamps. This enables precise control over both the content and temporal structure of the generated audio. Despite recent progress, existing methods still face inherent trade-offs among accurate temporal localization, open-vocabulary scalability, and practical efficiency. To address these challenges, we propose DegDiT, a novel dynamic event graph-guided diffusion transformer framework for open-vocabulary controllable audio generation. DegDiT encodes the events in the description as structured dynamic graphs. The nodes in each graph are designed to represent three aspects: semantic features, temporal attributes, and inter-event connections. A graph transformer is employed to integrate these nodes and produce contextualized event embeddings that serve as guidance for the diffusion model. To ensure high-quality and diverse training data, we introduce a quality-balanced data selection pipeline that combines hierarchical event annotation with multi-criteria quality scoring, resulting in a curated dataset with semantic diversity. Furthermore, we present consensus preference optimization, facilitating audio generation through consensus among multiple reward signals. Extensive experiments on AudioCondition, DESED, and AudioTime datasets demonstrate that DegDiT achieves state-of-the-art performances across a variety of objective and subjective evaluation metrics.
[691] A Lightweight Architecture for Multi-instrument Transcription with Practical Optimizations
Ruigang Li, Yongxu Zhu
Main category: cs.SD
TL;DR: Lightweight multi-instrument transcription model with timbre encoder and deep clustering for joint transcription and separation of arbitrary instruments
Details
Motivation: Address limitations of existing multi-timbre transcription models: poor generalization beyond pre-trained instruments, rigid source-count constraints, and high computational demands that hinder deployment on low-resource devicesMethod: Extends timbre-agnostic transcription backbone with dedicated timbre encoder and performs deep clustering at note level for joint transcription and dynamic separation. Uses spectral normalization, dilated convolutions, and contrastive clustering for efficiency and robustness
Result: Achieves competitive performance with heavier baselines in transcription accuracy and separation quality despite small size and fast inference. Shows promising generalization ability
Conclusion: Model is highly suitable for real-world deployment in practical and resource-constrained settings, addressing key limitations of existing approaches
Abstract: Existing multi-timbre transcription models struggle with generalization beyond pre-trained instruments, rigid source-count constraints, and high computational demands that hinder deployment on low-resource devices. We address these limitations with a lightweight model that extends a timbre-agnostic transcription backbone with a dedicated timbre encoder and performs deep clustering at the note level, enabling joint transcription and dynamic separation of arbitrary instruments given a specified number of instrument classes. Practical optimizations including spectral normalization, dilated convolutions, and contrastive clustering further improve efficiency and robustness. Despite its small size and fast inference, the model achieves competitive performance with heavier baselines in terms of transcription accuracy and separation quality, and shows promising generalization ability, making it highly suitable for real-world deployment in practical and resource-constrained settings.
[692] Cross-Lingual F5-TTS: Towards Language-Agnostic Voice Cloning and Speech Synthesis
Qingyu Liu, Yushen Chen, Zhikang Niu, Chunhui Wang, Yunting Yang, Bowen Zhang, Jian Zhao, Pengcheng Zhu, Kai Yu, Xie Chen
Main category: cs.SD
TL;DR: Cross-Lingual F5-TTS enables cross-lingual voice cloning without requiring audio prompt transcripts, using forced alignment for word boundaries and speaking rate predictors for duration modeling.
Details
Motivation: Current flow-matching TTS models require reference transcripts for audio prompts, preventing cross-lingual voice cloning when transcripts are unavailable, especially for unseen languages.Method: Uses forced alignment to preprocess audio prompts for word boundaries, trains speaking rate predictors at different linguistic granularities for duration modeling, and excludes transcripts during training.
Result: Matches the performance of F5-TTS while enabling cross-lingual voice cloning without audio prompt transcripts.
Conclusion: The framework successfully enables cross-lingual voice cloning by eliminating the dependency on audio prompt transcripts through forced alignment and speaking rate prediction.
Abstract: Flow-matching-based text-to-speech (TTS) models have shown high-quality speech synthesis. However, most current flow-matching-based TTS models still rely on reference transcripts corresponding to the audio prompt for synthesis. This dependency prevents cross-lingual voice cloning when audio prompt transcripts are unavailable, particularly for unseen languages. The key challenges for flow-matching-based TTS models to remove audio prompt transcripts are identifying word boundaries during training and determining appropriate duration during inference. In this paper, we introduce Cross-Lingual F5-TTS, a framework that enables cross-lingual voice cloning without audio prompt transcripts. Our method preprocesses audio prompts by forced alignment to obtain word boundaries, enabling direct synthesis from audio prompts while excluding transcripts during training. To address the duration modeling challenge, we train speaking rate predictors at different linguistic granularities to derive duration from speaker pace. Experiments show that our approach matches the performance of F5-TTS while enabling cross-lingual voice cloning.
[693] VCB Bench: An Evaluation Benchmark for Audio-Grounded Large Language Model Conversational Agents
Jiliang Hu, Wenfu Wang, Zuchao Li, Chenxing Li, Yiyang Zhao, Hanzhao Li, Liqiang Zhang, Meng Yu, Dong Yu
Main category: cs.SD
TL;DR: VCB Bench is a high-quality Chinese benchmark for evaluating Large Audio Language Models using real human speech across instruction following, knowledge understanding, and robustness dimensions.
Details
Motivation: Existing audio language model benchmarks are limited - they are mainly English-centric, rely on synthetic speech, and lack comprehensive discriminative evaluation across multiple dimensions.Method: Created VCB Bench, a Chinese benchmark built entirely on real human speech that evaluates LALMs from three perspectives: instruction following (including speech-level control), knowledge understanding (general knowledge, reasoning, daily dialogue), and robustness (stability under perturbations).
Result: Experiments on representative LALMs revealed notable performance gaps and highlighted future directions for improvement.
Conclusion: VCB Bench provides a reproducible and fine-grained evaluation framework with standardized methodology and practical insights for advancing Chinese voice conversational models.
Abstract: Recent advances in large audio language models (LALMs) have greatly enhanced multimodal conversational systems. However, existing benchmarks remain limited – they are mainly English-centric, rely on synthetic speech, and lack comprehensive, discriminative evaluation across multiple dimensions. To address these gaps, we present Voice Chat Bot Bench (VCB Bench) – a high-quality Chinese benchmark built entirely on real human speech. VCB Bench evaluates LALMs from three complementary perspectives: instruction following (including speech-level control beyond text commands), knowledge understanding (general knowledge, reasoning, and daily dialogue), and robustness (stability under perturbations in content, environment, and speaker traits). Experiments on representative LALMs reveal notable performance gaps and highlight future directions for improvement. VCB Bench provides a reproducible and fine-grained evaluation framework, offering standardized methodology and practical insights for advancing Chinese voice conversational models.
cs.LG
[694] Attractor Patch Networks: Reducing Catastrophic Forgetting with Routed Low-Rank Patch Experts
Shashank
Main category: cs.LG
TL;DR: APN replaces Transformer FFNs with patch experts selected by similarity routing, enabling conditional computation and better continual learning with less interference.
Details
Motivation: Standard Transformer FFNs are dense and globally shared, causing inefficient computation (same compute for all tokens) and interference in continual learning when shared weights are updated.Method: Attractor Patch Networks (APN) use a bank of patch experts with similarity routing to select top-k patches per token, each emitting low-rank residual updates based on compact codes, preserving Transformer interface.
Result: APN achieves competitive perplexity (4.57 vs 4.32 PPL) and dramatically better continual adaptation: 2.6× better retention and 2.8× better adaptation compared to fine-tuning dense FFNs.
Conclusion: APN provides an architectural primitive for conditional, context-specialized transformations that reduces interference and improves continual learning while maintaining Transformer compatibility.
Abstract: Transformers achieve strong language modeling accuracy, yet their position-wise feed-forward networks (FFNs) are dense, globally shared, and typically updated end to end. These properties create two practical tensions. First, dense FFNs spend the same compute on every token regardless of context, and they allocate capacity uniformly even when language exhibits highly clustered context structure. Second, continual learning, in the sense of updating the model while serving a data stream, often produces interference because a small update touches broadly shared weights. We propose Attractor Patch Networks (APN), a plug-compatible replacement for the Transformer FFN. APN is a bank of patch experts. A similarity router selects a small top-k set of patches for each token by matching the token representation to learned prototypes. Each selected patch emits a low-rank residual update conditioned on a compact code. The architecture yields conditional, context-specialized nonlinear transformations while preserving the standard Transformer interface. This paper focuses on APN as an architectural primitive. We formalize APN, analyze its expressivity as a piecewise low-rank residual function class, and derive simple interference and stability arguments that make APN naturally compatible with continual learning. In experiments on character-level language modeling, APN achieves competitive perplexity (4.57 vs 4.32 PPL) while enabling dramatically better continual adaptation: when adapting to a shifted domain, APN achieves 2.6 times better retention (11.1 vs 29.4 PPL on the original domain) and 2.8 times better adaptation (6.4 vs 17.8 PPL on the new domain) compared to global fine-tuning of a dense FFN baseline.
[695] Neural Sabermetrics with World Model: Play-by-play Predictive Modeling with Large Language Model
Young Jin Ahn, Yiyang Du, Zheyuan Zhang, Haisen Kang
Main category: cs.LG
TL;DR: A Large Language Model-based world model for baseball that predicts game evolution pitch-by-pitch using MLB tracking data, outperforming existing neural baselines.
Details
Motivation: Classical baseball statistics are valuable for valuation and retrospective analysis but lack generative modeling of how games unfold pitch-by-pitch. Existing approaches are limited to single-step prediction or post-hoc analysis, creating a need for a comprehensive world model.Method: Treat baseball games as long auto-regressive sequences of events and continuously pretrain a single LLM on over 10 years of MLB tracking data (7M+ pitch sequences, ~3B tokens). The model predicts multiple aspects of game evolution within a unified framework.
Result: Outperforms existing neural baselines: correctly predicts ~64% of next pitches within a plate appearance and ~78% of batter swing decisions. Evaluated on both in-distribution regular-season and out-of-distribution postseason games.
Conclusion: LLMs can serve as effective world models for sports, demonstrating their capability to model complex sequential decision-making processes in baseball games.
Abstract: Classical sabermetrics has profoundly shaped baseball analytics by summarizing long histories of play into compact statistics. While these metrics are invaluable for valuation and retrospective analysis, they do not define a generative model of how baseball games unfold pitch by pitch, leaving most existing approaches limited to single-step prediction or post-hoc analysis. In this work, we present Neural Sabermetrics with World Model, a Large Language Model (LLM) based play-by-play world model for baseball. We cast baseball games as long auto-regressive sequences of events and continuously pretrain a single LLM on more than ten years of Major League Baseball (MLB) tracking data, comprising over seven million pitch sequences and approximately three billion tokens. The resulting model is capable of predicting multiple aspects of game evolution within a unified framework. We evaluate our model on both in-distribution regular-season data and out-of-distribution postseason games and compare against strong neural baselines from prior work. Despite using a single backbone model, our approach outperforms the performance of existing baselines, (1) correctly predicting approximately 64% of next pitches within a plate appearance and (2) 78% of batter swing decisions, suggesting that LLMs can serve as effective world models for sports.
[696] Video-based Music Generation
Serkan Sulun
Main category: cs.LG
TL;DR: EMSYC is an automatic video-to-music generation system that creates emotionally and rhythmically synchronized music for videos using novel emotion classification, continuous emotion-based MIDI generation, and temporal boundary conditioning.
Details
Motivation: With growing video content online, finding suitable soundtracks is challenging. Content creators need automatic solutions to generate music that enhances videos without requiring composition skills or licensing.Method: 1) Novel video emotion classifier using frozen pretrained networks with trainable fusion layers; 2) Large-scale emotion-labeled MIDI dataset; 3) Emotion-based MIDI generator conditioned on continuous emotional values; 4) Temporal boundary conditioning with “boundary offset encodings” to align music with scene changes.
Result: State-of-the-art results on Ekman-6 and MovieNet emotion classification. User studies show EMSYNC outperforms existing methods in music richness, emotional alignment, temporal synchronization, and overall preference.
Conclusion: EMSYNC is a fully automatic video-based music generator that successfully combines emotion understanding, continuous emotion conditioning, and temporal synchronization to create high-quality video soundtracks.
Abstract: As the volume of video content on the internet grows rapidly, finding a suitable soundtrack remains a significant challenge. This thesis presents EMSYNC (EMotion and SYNChronization), a fast, free, and automatic solution that generates music tailored to the input video, enabling content creators to enhance their productions without composing or licensing music. Our model creates music that is emotionally and rhythmically synchronized with the video. A core component of EMSYNC is a novel video emotion classifier. By leveraging pretrained deep neural networks for feature extraction and keeping them frozen while training only fusion layers, we reduce computational complexity while improving accuracy. We show the generalization abilities of our method by obtaining state-of-the-art results on Ekman-6 and MovieNet. Another key contribution is a large-scale, emotion-labeled MIDI dataset for affective music generation. We then present an emotion-based MIDI generator, the first to condition on continuous emotional values rather than discrete categories, enabling nuanced music generation aligned with complex emotional content. To enhance temporal synchronization, we introduce a novel temporal boundary conditioning method, called “boundary offset encodings,” aligning musical chords with scene changes. Combining video emotion classification, emotion-based music generation, and temporal boundary conditioning, EMSYNC emerges as a fully automatic video-based music generator. User studies show that it consistently outperforms existing methods in terms of music richness, emotional alignment, temporal synchronization, and overall preference, setting a new state-of-the-art in video-based music generation.
[697] Lagged backward-compatible physics-informed neural networks for unsaturated soil consolidation analysis
Dong Li, Shuai Huang, Yapeng Cao, Yujun Cui, Xiaobin Wei, Hongtao Cao
Main category: cs.LG
TL;DR: LBC-PINN framework for simulating 1D unsaturated soil consolidation using physics-informed neural networks with logarithmic time segmentation and transfer learning
Details
Motivation: To address challenges in simulating coupled air and water pressure dissipation across multi-scale time domains in unsaturated soil consolidation under long-term loadingMethod: Lagged Backward-Compatible Physics-Informed Neural Network with logarithmic time segmentation, lagged compatibility loss enforcement, and segment-wise transfer learning
Result: Accurate prediction of pore pressures with mean absolute errors below 1e-2 for up to 1e10 seconds, validated against FEM; robust across wide permeability ratios
Conclusion: LBC-PINN effectively handles multi-scale temporal challenges in unsaturated soil consolidation with computational efficiency and accuracy
Abstract: This study develops a Lagged Backward-Compatible Physics-Informed Neural Network (LBC-PINN) for simulating and inverting one-dimensional unsaturated soil consolidation under long-term loading. To address the challenges of coupled air and water pressure dissipation across multi-scale time domains, the framework integrates logarithmic time segmentation, lagged compatibility loss enforcement, and segment-wise transfer learning. In forward analysis, the LBC-PINN with recommended segmentation schemes accurately predicts pore air and pore water pressure evolution. Model predictions are validated against finite element method (FEM) results, with mean absolute errors below 1e-2 for time durations up to 1e10 seconds. A simplified segmentation strategy based on the characteristic air-phase dissipation time improves computational efficiency while preserving predictive accuracy. Sensitivity analyses confirm the robustness of the framework across air-to-water permeability ratios ranging from 1e-3 to 1e3.
[698] Hybrid Feedback-Guided Optimal Learning for Wireless Interactive Panoramic Scene Delivery
Xiaoyi Wu, Juaren Steiger, Bin Li, R. Srikant
Main category: cs.LG
TL;DR: AdaPort: A hybrid online learning algorithm for panoramic content delivery in VR/AR that combines full-information and bandit feedback to optimize viewport prediction and transmission under bandwidth constraints.
Details
Motivation: VR/AR applications require high frame rates, low latency, and synchronization between physical/virtual environments. Edge servers must render panoramic content, predict head motion, and transmit viewport portions within bandwidth limits, with two feedback signals: prediction feedback (viewport coverage) and transmission feedback (packet delivery).Method: Proposes a two-level hybrid feedback model combining full-information and bandit feedback. Introduces AdaPort algorithm that leverages both feedback types: prediction feedback can be retrospectively computed for all candidate portions (full-information), while transmission feedback is bandit-style. Derives instance-dependent regret bounds and develops an algorithm matching lower bounds asymptotically.
Result: AdaPort achieves instance-dependent regret upper bound matching the lower bound asymptotically. Real-world trace-driven simulations show AdaPort consistently outperforms state-of-the-art baseline methods for panoramic content delivery in VR/AR.
Conclusion: The hybrid feedback model better captures real-world VR/AR content delivery characteristics. AdaPort effectively combines both feedback types to improve learning efficiency and performance compared to prior multi-armed bandit approaches.
Abstract: Immersive applications such as virtual and augmented reality impose stringent requirements on frame rate, latency, and synchronization between physical and virtual environments. To meet these requirements, an edge server must render panoramic content, predict user head motion, and transmit a portion of the scene that is large enough to cover the user viewport while remaining within wireless bandwidth constraints. Each portion produces two feedback signals: prediction feedback, indicating whether the selected portion covers the actual viewport, and transmission feedback, indicating whether the corresponding packets are successfully delivered. Prior work models this problem as a multi-armed bandit with two-level bandit feedback, but fails to exploit the fact that prediction feedback can be retrospectively computed for all candidate portions once the user head pose is observed. As a result, prediction feedback constitutes full-information feedback rather than bandit feedback. Motivated by this observation, we introduce a two-level hybrid feedback model that combines full-information and bandit feedback, and formulate the portion selection problem as an online learning task under this setting. We derive an instance-dependent regret lower bound for the hybrid feedback model and propose AdaPort, a hybrid learning algorithm that leverages both feedback types to improve learning efficiency. We further establish an instance-dependent regret upper bound that matches the lower bound asymptotically, and demonstrate through real-world trace driven simulations that AdaPort consistently outperforms state-of-the-art baseline methods.
[699] Rho-Perfect: Correlation Ceiling For Subjective Evaluation Datasets
Fredrik Cumlin
Main category: cs.LG
TL;DR: ρ-Perfect estimates the maximum achievable correlation between models and human ratings on subjective datasets by accounting for inherent rating noise.
Details
Motivation: Subjective ratings contain inherent noise that limits model-human correlation, but this reliability issue is rarely quantified. Researchers need a way to distinguish between model limitations and data quality issues.Method: Define ρ-Perfect as the correlation between a perfect predictor and human ratings, derive an estimate based on heteroscedastic noise scenarios common in subjective datasets, and validate using test-retest correlation.
Result: ρ-Perfect squared estimates test-retest correlation, validated on a speech quality dataset. The measure can distinguish between model limitations and data quality issues.
Conclusion: ρ-Perfect provides a practical estimation of the highest achievable correlation on subjectively rated datasets, helping researchers understand the fundamental limits of model performance due to rating noise.
Abstract: Subjective ratings contain inherent noise that limits the model-human correlation, but this reliability issue is rarely quantified. In this paper, we present $ρ$-Perfect, a practical estimation of the highest achievable correlation of a model on subjectively rated datasets. We define $ρ$-Perfect to be the correlation between a perfect predictor and human ratings, and derive an estimate of the value based on heteroscedastic noise scenarios, a common occurrence in subjectively rated datasets. We show that $ρ$-Perfect squared estimates test-retest correlation and use this to validate the estimate. We demonstrate the use of $ρ$-Perfect on a speech quality dataset and show how the measure can distinguish between model limitations and data quality issues.
[700] TransConv-DDPM: Enhanced Diffusion Model for Generating Time-Series Data in Healthcare
Md Shahriar Kabir, Sana Alamgeer, Minakshi Debnath, Anne H. H. Ngu
Main category: cs.LG
TL;DR: TransConv-DDPM: A diffusion-based generative model for physiological time-series data that combines U-Net, multi-scale convolutions, and transformers to capture temporal dependencies, showing improved performance on medical datasets.
Details
Motivation: Real-world clinical data scarcity hinders AI model training for medical diagnostics. While generative AI helps in vision/NLP domains, physiological time-series data generation is challenging due to complexity and variability.Method: Uses denoising diffusion probabilistic model (DDPM) with U-Net architecture enhanced by multi-scale convolution modules and transformer layers to capture both global and local temporal dependencies in time-series data.
Result: Outperformed TimeGAN and Diffusion-TS on three datasets, especially SmartFallMM and EEG datasets. Synthetic fall data improved predictive model performance by 13.64% F1-score and 14.93% accuracy over baseline.
Conclusion: TransConv-DDPM effectively generates high-quality synthetic physiological time-series data, addressing data scarcity in medical AI applications and improving model performance.
Abstract: The lack of real-world data in clinical fields poses a major obstacle in training effective AI models for diagnostic and preventive tools in medicine. Generative AI has shown promise in increasing data volume and enhancing model training, particularly in computer vision and natural language processing (NLP) domains. However, generating physiological time-series data, a common type in medical AI applications, presents unique challenges due to its inherent complexity and variability. This paper introduces TransConv-DDPM, an enhanced generative AI method for biomechanical and physiological time-series data generation. The model employs a denoising diffusion probabilistic model (DDPM) with U-Net, multi-scale convolution modules, and a transformer layer to capture both global and local temporal dependencies. We evaluated TransConv-DDPM on three diverse datasets, generating both long and short-sequence time-series data. Quantitative comparisons against state-of-the-art methods, TimeGAN and Diffusion-TS, using four performance metrics, demonstrated promising results, particularly on the SmartFallMM and EEG datasets, where it effectively captured the more gradual temporal change patterns between data points. Additionally, a utility test on the SmartFallMM dataset revealed that adding synthetic fall data generated by TransConv-DDPM improved predictive model performance, showing a 13.64% improvement in F1-score and a 14.93% increase in overall accuracy compared to the baseline model trained solely on fall data from the SmartFallMM dataset. These findings highlight the potential of TransConv-DDPM to generate high-quality synthetic data for real-world applications.
[701] AVERE: Improving Audiovisual Emotion Reasoning with Preference Optimization
Ashutosh Chaubey, Jiacheng Pang, Maksim Siniukov, Mohammad Soleymani
Main category: cs.LG
TL;DR: EmoReAlM benchmark evaluates multimodal LLMs on emotion understanding, addressing spurious associations and hallucinations, with AVEm-DPO optimization improving performance by 6-19%.
Details
Motivation: Current multimodal LLMs for emotion understanding suffer from two key issues: spurious associations between emotions and irrelevant audiovisual cues, and hallucinations of audiovisual cues driven by text priors in the language model backbone.Method: Introduces EmoReAlM benchmark to evaluate MLLMs on cue-emotion associations, hallucinations, and modality agreement. Proposes AVEm-DPO preference optimization technique that aligns responses with audiovisual inputs and emotion queries, constructing preferences over problematic responses and including regularization to penalize text prior reliance.
Result: Experimental results on DFEW, RAVDESS and EMER datasets show the method significantly improves baseline models with 6-19% relative performance gains in zero-shot settings.
Conclusion: Provides both a rigorous benchmark and robust optimization framework for principled evaluation and improvement of MLLMs for emotion understanding and social AI applications.
Abstract: Emotion understanding is essential for building socially intelligent agents. Although recent multimodal large language models have shown strong performance on this task, two key challenges remain - spurious associations between emotions and irrelevant audiovisual cues, and hallucinations of audiovisual cues driven by text priors in the language model backbone. To quantify and understand these issues, we introduce EmoReAlM, a benchmark designed to evaluate MLLMs for cue-emotion associations, hallucinations and modality agreement. We then propose AVEm-DPO, a preference optimization technique that aligns model responses with both audiovisual inputs and emotion-centric queries. Specifically, we construct preferences over responses exhibiting spurious associations or hallucinations, and audiovisual input pairs guided by textual prompts. We also include a regularization term that penalizes reliance on text priors, thereby mitigating modality-specific cue hallucinations. Experimental results on DFEW, RAVDESS and EMER demonstrate that our method significantly improves the performance of the reference baseline models with 6-19% of relative performance gains in zero-shot settings. By providing both a rigorous benchmark and a robust optimization framework, this work enables principled evaluation and improvement of MLLMs for emotion understanding and social AI. Code, models and benchmark will be released at https://avere-iclr.github.io.
[702] TACIT: Transformation-Aware Capturing of Implicit Thought
Daniel Nobrega
Main category: cs.LG
TL;DR: TACIT is a diffusion-based transformer for visual reasoning that operates in pixel space using rectified flow, enabling direct visualization of reasoning processes. It demonstrates maze-solving capabilities with dramatic efficiency improvements and reveals a striking “eureka moment” pattern in reasoning emergence.
Details
Motivation: To develop an interpretable visual reasoning system that operates entirely in pixel space, enabling direct visualization of reasoning processes without language mediation. The goal is to understand how neural networks develop implicit reasoning strategies that operate "below and before language."Method: Uses a diffusion-based transformer architecture with rectified flow for noise-free flow matching. Operates entirely in pixel space rather than language space. Trained on 1 million synthetic maze pairs, transforming images of unsolved mazes into solutions using only 10 Euler steps (vs. 100-1000 for typical diffusion models).
Result: Achieved 192x reduction in training loss over 100 epochs and 22.7x improvement in L2 distance to ground truth. Most remarkably, discovered a phase transition phenomenon: solutions remain invisible for 68% of transformation (zero recall), then emerge abruptly at t=0.70 within just 2% of the process. 100% of samples show simultaneous emergence across all spatial regions.
Conclusion: TACIT demonstrates that neural networks can develop holistic, non-algorithmic reasoning strategies in pixel space. The “eureka moment” pattern (long incubation followed by sudden crystallization) parallels insight phenomena in human cognition, providing evidence for implicit reasoning that operates below language.
Abstract: We present TACIT (Transformation-Aware Capturing of Implicit Thought), a diffusion-based transformer for interpretable visual reasoning. Unlike language-based reasoning systems, TACIT operates entirely in pixel space using rectified flow, enabling direct visualization of the reasoning process at each inference step. We demonstrate the approach on maze-solving, where the model learns to transform images of unsolved mazes into solutions. Key results on 1 million synthetic maze pairs include:
- 192x reduction in training loss over 100 epochs
- 22.7x improvement in L2 distance to ground truth
- Only 10 Euler steps required (vs. 100-1000 for typical diffusion models) Quantitative analysis reveals a striking phase transition phenomenon: the solution remains invisible for 68% of the transformation (zero recall), then emerges abruptly at t=0.70 within just 2% of the process. Most remarkably, 100% of samples exhibit simultaneous emergence across all spatial regions, ruling out sequential path construction and providing evidence for holistic rather than algorithmic reasoning. This “eureka moment” pattern – long incubation followed by sudden crystallization – parallels insight phenomena in human cognition. The pixel-space design with noise-free flow matching provides a foundation for understanding how neural networks develop implicit reasoning strategies that operate below and before language.
[703] Hybrid Dual-Path Linear Transformations for Efficient Transformer Architectures
Vladimer Khasia
Main category: cs.LG
TL;DR: HDPL decomposes Transformer linear layers into sparse local and low-rank global pathways, improving efficiency and performance while creating a probabilistic latent space for control and adaptation.
Details
Motivation: Standard Transformer dense linear transformations are inefficient and lack structural bias for distinguishing local feature preservation from global context integration.Method: Introduces Hybrid Dual-Path Linear (HDPL) operator with two pathways: sparse block-diagonal for local processing and low-rank VAE bottleneck for global context. Replaces specific projections (Query, Key, Value, Gate, Up) with HDPL while keeping dense layers for aggregation.
Result: Outperforms standard Llama-style baseline on FineWeb-Edu dataset, reducing validation loss while cutting parameter count by 6.8%.
Conclusion: HDPL achieves better efficiency-performance balance and creates a probabilistic latent space enabling new pathways for control, adaptation, interpretability, and cross-modal synchronization.
Abstract: Standard Transformer architectures rely heavily on dense linear transformations, treating feature projection as a monolithic, full-rank operation. We argue that this formulation is inefficient and lacks the structural inductive bias necessary for distinguishing between local feature preservation and global context integration. To address this, we introduce the Hybrid Dual-Path Linear (HDPL) operator, which decomposes the affine transformation into two topologically distinct pathways: a sparse block-diagonal component for high-rank local processing, and a low-rank Variational Autoencoder (VAE) bottleneck for global context regularization. By “surgically” replacing specific projections (Query, Key, Value, Gate, Up) with HDPL operators while retaining standard dense layers for aggregation (Output, Down), we achieve a superior balance of efficiency and representational power. Experiments on the FineWeb-Edu dataset demonstrate that the HDPL architecture outperforms a standard Llama-style baseline, reducing validation loss while simultaneously reducing parameter count by 6.8%. Beyond immediate performance gains, we discuss how the explicit materialization of a probabilistic latent space within the Transformer backbone serves as a vital architectural affordance, offering new pathways for inference-time or hypernetwork induced control, continual adaptation, interpretability, and cross-model or cross-modal synchronization. The code is available at https://github.com/VladimerKhasia/HDPL
[704] The Optimal Token Baseline: Variance Reduction for Long-Horizon LLM-RL
Yingru Li, Jiawei Xu, Ziniu Li, Jiacai Liu, Wei Liu, Yuxuan Tong, Longtao Zheng, Zhenghai Xue, Yaxiang Zhang, Tianle Cai, Ge Zhang, Qian Liu, Baoxiang Wang
Main category: cs.LG
TL;DR: OTB: Optimal Token Baseline for RL in LLMs reduces gradient variance by weighting updates inversely to cumulative gradient norms, using efficient Logit-Gradient Proxy approximation.
Details
Motivation: RL for LLMs suffers from training collapse in long-horizon tasks due to exploding gradient variance. Traditional baselines (value models or group-based) are either hard to optimize or ignore sequence/token heterogeneity. Classic optimal baseline theory reduces variance but is computationally prohibitive and ignores token-level differences.Method: Derived Optimal Token Baseline (OTB) from first principles, proving gradient updates should be weighted inversely to their cumulative gradient norm. Proposed Logit-Gradient Proxy to efficiently approximate gradient norm using only forward-pass probabilities without backpropagation.
Result: Achieves training stability and matches performance of large group sizes (N=32) with only N=4, reducing token consumption by over 65% across single-turn and tool-integrated reasoning tasks.
Conclusion: OTB provides an efficient, theoretically grounded solution to gradient variance in RL for LLMs, enabling stable training with significantly reduced computational cost.
Abstract: Reinforcement Learning (RL) for Large Language Models (LLMs) often suffers from training collapse in long-horizon tasks due to exploding gradient variance. To mitigate this, a baseline is commonly introduced for advantage computation; however, traditional value models remain difficult to optimize, and standard group-based baselines overlook sequence heterogeneity. Although classic optimal baseline theory can achieve global variance reduction, it neglects token heterogeneity and requires prohibitive gradient-based computation. In this work, we derive the Optimal Token Baseline (OTB) from first principles, proving that gradient updates should be weighted inversely to their cumulative gradient norm. To ensure efficiency, we propose the Logit-Gradient Proxy that approximates the gradient norm using only forward-pass probabilities. Our method achieves training stability and matches the performance of large group sizes ($N=32$) with only $N=4$, reducing token consumption by over 65% across single-turn and tool-integrated reasoning tasks.
[705] Attention-Driven Framework for Non-Rigid Medical Image Registration
Muhammad Zafar Iqbal, Ghazanfar Farooq Siddiqui, Anwar Ul Haq, Imran Razzak
Main category: cs.LG
TL;DR: AD-RegNet: A novel attention-driven framework for non-rigid medical image registration using 3D UNet with bidirectional cross-attention and regional adaptive attention mechanisms for accurate alignment of medical images with large deformations.
Details
Motivation: Accurate medical image registration with large deformations while preserving anatomical plausibility remains challenging despite advances in deep learning methods. Current approaches need improvement in handling complex deformations and maintaining anatomical integrity.Method: Proposes AD-RegNet with 3D UNet backbone, bidirectional cross-attention for establishing correspondences between moving and fixed images at multiple scales, regional adaptive attention focusing on anatomically relevant structures, and multi-resolution deformation field synthesis.
Result: Achieves competitive performance with state-of-the-art methods on IXI (brain MRI) and DIRLab (thoracic 4D CT) datasets, maintaining balance between registration accuracy and computational efficiency. Comprehensive evaluation shows improved alignment accuracy with anatomically plausible deformations.
Conclusion: Attention-guided registration improves alignment accuracy while ensuring anatomically plausible deformations, making the method suitable for clinical applications across different anatomical structures and imaging modalities.
Abstract: Deformable medical image registration is a fundamental task in medical image analysis with applications in disease diagnosis, treatment planning, and image-guided interventions. Despite significant advances in deep learning based registration methods, accurately aligning images with large deformations while preserving anatomical plausibility remains a challenging task. In this paper, we propose a novel Attention-Driven Framework for Non-Rigid Medical Image Registration (AD-RegNet) that employs attention mechanisms to guide the registration process. Our approach combines a 3D UNet backbone with bidirectional cross-attention, which establishes correspondences between moving and fixed images at multiple scales. We introduce a regional adaptive attention mechanism that focuses on anatomically relevant structures, along with a multi-resolution deformation field synthesis approach for accurate alignment. The method is evaluated on two distinct datasets: DIRLab for thoracic 4D CT scans and IXI for brain MRI scans, demonstrating its versatility across different anatomical structures and imaging modalities. Experimental results demonstrate that our approach achieves performance competitive with state-of-the-art methods on the IXI and DIRLab datasets. The proposed method maintains a favorable balance between registration accuracy and computational efficiency, making it suitable for clinical applications. A comprehensive evaluation using normalized cross-correlation (NCC), mean squared error (MSE), structural similarity (SSIM), Jacobian determinant, and target registration error (TRE) indicates that attention-guided registration improves alignment accuracy while ensuring anatomically plausible deformations.
[706] Finding Connections: Membership Inference Attacks for the Multi-Table Synthetic Data Setting
Joshua Ward, Chi-Hua Wang, Guang Cheng
Main category: cs.LG
TL;DR: Proposes MT-MIA, a novel membership inference attack for synthetic relational data that targets user-level privacy vulnerabilities across interconnected tables, showing single-table attacks underestimate privacy leakage.
Details
Motivation: Real-world data exists in relational databases with interconnected tables, but existing synthetic data generation and privacy auditing methods focus on single tables, underestimating user-level privacy risks from inter-tabular relationships.Method: Introduces Multi-Table Membership Inference Attack (MT-MIA) using Heterogeneous Graph Neural Networks to learn representations of user entities across multiple interconnected tables under a No-Box threat model.
Result: MT-MIA demonstrates significant user-level privacy vulnerabilities in state-of-the-art relational synthetic data generators that are underestimated by single-table attacks, and identifies where this leakage occurs.
Conclusion: User-level privacy auditing for synthetic relational data requires multi-table approaches; MT-MIA reveals critical vulnerabilities in current relational synthetic data generation methods.
Abstract: Synthetic tabular data has gained attention for enabling privacy-preserving data sharing. While substantial progress has been made in single-table synthetic generation where data are modeled at the row or item level, most real-world data exists in relational databases where a user’s information spans items across multiple interconnected tables. Recent advances in synthetic relational data generation have emerged to address this complexity, yet release of these data introduce unique privacy challenges as information can be leaked not only from individual items but also through the relationships that comprise a complete user entity. To address this, we propose a novel Membership Inference Attack (MIA) setting to audit the empirical user-level privacy of synthetic relational data and show that single-table MIAs that audit at an item level underestimate user-level privacy leakage. We then propose Multi-Table Membership Inference Attack (MT-MIA), a novel adversarial attack under a No-Box threat model that targets learned representations of user entities via Heterogeneous Graph Neural Networks. By incorporating all connected items for a user, MT-MIA better targets user-level vulnerabilities induced by inter-tabular relationships than existing attacks. We evaluate MT-MIA on a range of real-world multi-table datasets and demonstrate that this vulnerability exists in state-of-the-art relational synthetic data generators, employing MT-MIA to additionally study where this leakage occurs.
[707] Landscaper: Understanding Loss Landscapes Through Multi-Dimensional Topological Analysis
Jiaqing Chen, Nicholas Hadler, Tiankai Xie, Rostyslav Hnatyshyn, Caleb Geniesse, Yaoqing Yang, Michael W. Mahoney, Talita Perciano, John F. Hartwig, Ross Maciejewski, Gunther H. Weber
Main category: cs.LG
TL;DR: Landscaper is an open-source Python package for high-dimensional loss landscape analysis using Hessian-based subspace construction and topological data analysis, with SMAD metric for quantifying landscape smoothness and revealing training transitions.
Details
Motivation: Traditional low-dimensional loss landscape analyses often miss complex topological features, limiting understanding of neural network optimization and generalization. There's a need for tools that can analyze arbitrary-dimensional loss landscapes to reveal geometric structures like basin hierarchy and connectivity.Method: Landscaper combines Hessian-based subspace construction with topological data analysis. It introduces the Saddle-Minimum Average Distance (SMAD) metric for quantifying landscape smoothness. The package enables analysis across various architectures and tasks, including pre-trained language models.
Result: Landscaper effectively reveals geometric structures in loss landscapes, with SMAD capturing training transitions like landscape simplification that conventional metrics miss. It performs well in chemical property prediction tasks where SMAD serves as a metric for out-of-distribution generalization.
Conclusion: Landscaper provides valuable insights for model diagnostics and architecture design, particularly in data-scarce scientific machine learning scenarios, by enabling detailed analysis of loss landscape geometry and topology.
Abstract: Loss landscapes are a powerful tool for understanding neural network optimization and generalization, yet traditional low-dimensional analyses often miss complex topological features. We present Landscaper, an open-source Python package for arbitrary-dimensional loss landscape analysis. Landscaper combines Hessian-based subspace construction with topological data analysis to reveal geometric structures such as basin hierarchy and connectivity. A key component is the Saddle-Minimum Average Distance (SMAD) for quantifying landscape smoothness. We demonstrate Landscaper’s effectiveness across various architectures and tasks, including those involving pre-trained language models, showing that SMAD captures training transitions, such as landscape simplification, that conventional metrics miss. We also illustrate Landscaper’s performance in challenging chemical property prediction tasks, where SMAD can serve as a metric for out-of-distribution generalization, offering valuable insights for model diagnostics and architecture design in data-scarce scientific machine learning scenarios.
[708] Featured Reproducing Kernel Banach Spaces for Learning and Neural Networks
Isabel de la Higuera, Francisco Herrera, M. Victoria Velasco
Main category: cs.LG
TL;DR: The paper develops a theoretical framework for learning in Banach spaces using featured reproducing kernel Banach spaces, extending kernel methods beyond Hilbert spaces to include neural networks with non-quadratic norms.
Details
Motivation: Many modern learning models like neural networks with non-quadratic norms operate in non-Hilbertian geometries that fall outside traditional reproducing kernel Hilbert space theory, requiring new theoretical foundations.Method: Develops functional-analytic framework for learning in Banach spaces using featured reproducing kernel Banach spaces, identifying structural conditions for feature maps, kernel constructions, and representer theorems beyond Hilbert spaces.
Result: Establishes existence results and conditional representer theorems for supervised learning as minimal-norm interpolation/regularization problems, extends theory to vector-valued spaces, and shows neural networks induce special instances of such spaces.
Conclusion: Provides unified function-space perspective connecting kernel methods and neural networks, clarifying when kernel-based learning principles extend beyond reproducing kernel Hilbert spaces to more general Banach space settings.
Abstract: Reproducing kernel Hilbert spaces provide a foundational framework for kernel-based learning, where regularization and interpolation problems admit finite-dimensional solutions through classical representer theorems. Many modern learning models, however – including fixed-architecture neural networks equipped with non-quadratic norms – naturally give rise to non-Hilbertian geometries that fall outside this setting. In Banach spaces, continuity of point-evaluation functionals alone is insufficient to guarantee feature representations or kernel-based learning formulations. In this work, we develop a functional-analytic framework for learning in Banach spaces based on the notion of featured reproducing kernel Banach spaces. We identify the precise structural conditions under which feature maps, kernel constructions, and representer-type results can be recovered beyond the Hilbertian regime. Within this framework, supervised learning is formulated as a minimal-norm interpolation or regularization problem, and existence results together with conditional representer theorems are established. We further extend the theory to vector-valued featured reproducing kernel Banach spaces and show that fixed-architecture neural networks naturally induce special instances of such spaces. This provides a unified function-space perspective on kernel methods and neural networks and clarifies when kernel-based learning principles extend beyond reproducing kernel Hilbert spaces.
[709] BONSAI: Bayesian Optimization with Natural Simplicity and Interpretability
Samuel Daulton, David Eriksson, Maximilian Balandat, Eytan Bakshy
Main category: cs.LG
TL;DR: BONSAI is a Bayesian optimization method that incorporates default configurations to prune low-impact parameter deviations while maintaining optimization performance.
Details
Motivation: Standard Bayesian optimization often pushes weakly relevant parameters to search space boundaries, making it difficult to distinguish important from spurious changes and increasing vetting burden when optimization objectives omit operational considerations. Many applications have carefully engineered default configurations that practitioners want to deviate from only when necessary.Method: BONSAI is a default-aware BO policy that prunes low-impact deviations from a default configuration while explicitly controlling the loss in acquisition value. It’s compatible with various acquisition functions (EI, GP-UCB) and theoretically bounds regret while maintaining the same no-regret property as vanilla GP-UCB under certain conditions.
Result: Empirical evaluation across real-world applications shows BONSAI substantially reduces the number of non-default parameters in recommended configurations while maintaining competitive optimization performance, with little effect on wall time.
Conclusion: BONSAI provides a practical Bayesian optimization approach that respects default configurations, reduces parameter changes to only necessary ones, and maintains optimization performance while being theoretically sound.
Abstract: Bayesian optimization (BO) is a popular technique for sample-efficient optimization of black-box functions. In many applications, the parameters being tuned come with a carefully engineered default configuration, and practitioners only want to deviate from this default when necessary. Standard BO, however, does not aim to minimize deviation from the default and, in practice, often pushes weakly relevant parameters to the boundary of the search space. This makes it difficult to distinguish between important and spurious changes and increases the burden of vetting recommendations when the optimization objective omits relevant operational considerations. We introduce BONSAI, a default-aware BO policy that prunes low-impact deviations from a default configuration while explicitly controlling the loss in acquisition value. BONSAI is compatible with a variety of acquisition functions, including expected improvement and upper confidence bound (GP-UCB). We theoretically bound the regret incurred by BONSAI, showing that, under certain conditions, it enjoys the same no-regret property as vanilla GP-UCB. Across many real-world applications, we empirically find that BONSAI substantially reduces the number of non-default parameters in recommended configurations while maintaining competitive optimization performance, with little effect on wall time.
[710] Convex Dominance in Deep Learning I: A Scaling Law of Loss and Learning Rate
Zhiqi Bu, Shiyun Xu, Jialin Mao
Main category: cs.LG
TL;DR: The paper examines convexity and Lipschitz continuity in deep learning optimization, showing that neural networks become weakly convex after initial training, enabling precise control of loss dynamics via learning rate schedules and establishing scaling laws.
Details
Motivation: Deep learning has non-convex loss landscapes that are difficult to analyze, but empirical observations show convex-like dynamics. The authors aim to understand if convexity and Lipschitz continuity concepts can be applied to better control optimization dynamics through learning rate scheduling.Method: The authors examine the applicability of convexity and Lipschitz continuity in deep learning optimization. They demonstrate that neural networks become weakly convex after initial training, and use this insight to derive an upper bound on the last iterate that predicts loss behavior. This informs optimal learning rate scaling.
Result: The paper shows that deep learning optimization becomes weakly convex after short training periods. Through convexity analysis, they build scaling laws for learning rates and losses that can extrapolate up to 80X across training horizons and 70X across model sizes.
Conclusion: Convexity and Lipschitz continuity concepts can be effectively applied to deep learning optimization, enabling precise control of loss dynamics and establishing scaling laws that generalize across training horizons and model sizes.
Abstract: Deep learning has non-convex loss landscape and its optimization dynamics is hard to analyze or control. Nevertheless, the dynamics can be empirically convex-like across various tasks, models, optimizers, hyperparameters, etc. In this work, we examine the applicability of convexity and Lipschitz continuity in deep learning, in order to precisely control the loss dynamics via the learning rate schedules. We illustrate that deep learning quickly becomes weakly convex after a short period of training, and the loss is predicable by an upper bound on the last iterate, which further informs the scaling of optimal learning rate. Through the lens of convexity, we build scaling laws of learning rates and losses that extrapolate as much as 80X across training horizons and 70X across model sizes.
[711] On Randomness in Agentic Evals
Bjarni Haukur Bjarnason, André Silva, Martin Monperrus
Main category: cs.LG
TL;DR: Agent evaluation benchmarks show high variance in single-run pass@1 scores, making small reported improvements unreliable; recommendations include multiple runs, statistical power analysis, and pass@k metrics.
Details
Motivation: Most agentic systems are evaluated using single-run pass@1 scores, assuming this provides reliable performance estimates. The authors question this assumption, noting that small reported improvements (2-3 percentage points) might reflect evaluation noise rather than genuine algorithmic progress.Method: Collected 60,000 agentic trajectories on SWE-Bench-Verified across three models and two scaffolds. Analyzed variance in pass@1 scores from single runs, conducted token-level analysis to understand when trajectories diverge, and examined how small differences cascade into different solution strategies.
Result: Found substantial variance: single-run pass@1 estimates vary by 2.2 to 6.0 percentage points depending on which run is selected, with standard deviations exceeding 1.5 percentage points even at temperature 0. Token-level analysis showed trajectories diverge early (within first few percent of tokens), and small differences cascade into different solution strategies.
Conclusion: Current single-run evaluation practices are unreliable for measuring small improvements. Recommended three practices: (1) estimate pass@1 from multiple independent runs, (2) use statistical power analysis to determine required runs, and (3) consider pass@k and pass^k metrics with k>1. These practices are essential for distinguishing genuine progress from statistical noise.
Abstract: Agentic systems are evaluated on benchmarks where agents interact with environments to solve tasks. Most papers report a pass@1 score computed from a single run per task, assuming this gives a reliable performance estimate. We test this assumption by collecting 60,000 agentic trajectories on SWE-Bench-Verified, spanning three models and two scaffolds. We find substantial variance: single-run pass@1 estimates vary by 2.2 to 6.0 percentage points depending on which run is selected, with standard deviations exceeding 1.5 percentage points even at temperature 0. This variance has critical implications: reported improvements of 2–3 percentage points may reflect evaluation noise rather than genuine algorithmic progress. Through token-level analysis, we show that trajectories diverge early, often within the first few percent of tokens, and that these small differences cascade into different solution strategies. To enable reliable evaluation of agentic systems, we recommend three concrete practices: (1) estimate pass@1 from multiple independent runs per task, especially when measuring small improvements, (2) use statistical power analysis to determine the number of runs needed to detect expected effect sizes, and (3) consider metrics like pass@k (optimistic bound) and pass^k (pessimistic bound) with k>1 to better characterize the full performance envelope. While these practices increase evaluation cost, they are essential for distinguishing genuine scientific progress from statistical noise.
[712] Beyond Pooling: Matching for Robust Generalization under Data Heterogeneity
Ayush Roy, Rudrasis Chakraborty, Lav Varshney, Vishnu Suresh Lokhande
Main category: cs.LG
TL;DR: A matching framework for pooling heterogeneous datasets that addresses distributional asymmetries and improves zero-shot generalization, particularly for medical anomaly detection.
Details
Motivation: Naive pooling of heterogeneous datasets across domains amplifies distributional asymmetries and yields biased estimators, especially in zero-shot generalization settings. This is problematic for applications like medical anomaly detection where data heterogeneity is extreme.Method: Proposes a matching framework that selects samples relative to an adaptive centroid and iteratively refines representation distribution. Uses double robustness and propensity score matching for domain inclusion to filter out confounding domains causing heterogeneity.
Result: Theoretical and empirical analyses show matching outperforms naive pooling and uniform subsampling under asymmetric meta-distributions, including non-Gaussian and multimodal real-world settings. Improvements translate to zero-shot medical anomaly detection.
Conclusion: The matching framework effectively addresses data heterogeneity in representation learning, providing robust performance for zero-shot generalization tasks like medical anomaly detection where distributional asymmetries are extreme.
Abstract: Pooling heterogeneous datasets across domains is a common strategy in representation learning, but naive pooling can amplify distributional asymmetries and yield biased estimators, especially in settings where zero-shot generalization is required. We propose a matching framework that selects samples relative to an adaptive centroid and iteratively refines the representation distribution. The double robustness and the propensity score matching for the inclusion of data domains make matching more robust than naive pooling and uniform subsampling by filtering out the confounding domains (the main cause of heterogeneity). Theoretical and empirical analyses show that, unlike naive pooling or uniform subsampling, matching achieves better results under asymmetric meta-distributions, which are also extended to non-Gaussian and multimodal real-world settings. Most importantly, we show that these improvements translate to zero-shot medical anomaly detection, one of the extreme forms of data heterogeneity and asymmetry. The code is available on https://github.com/AyushRoy2001/Beyond-Pooling.
[713] Mimetic Initialization of MLPs
Asher Trockman, J. Zico Kolter
Main category: cs.LG
TL;DR: Mimetic initialization extended to channel mixing layers (MLPs) by giving first layer nonzero mean, speeding up training on small vision tasks.
Details
Motivation: Previous mimetic initialization work only applied to spatial mixing layers; this paper aims to extend the approach to channel mixing layers (MLPs) to improve training efficiency.Method: Apply mimetic initialization to multilayer perceptrons by giving the first layer a nonzero mean, based on observations of trained weight structures.
Result: The simple technique speeds up training on small-scale vision tasks like CIFAR-10 and ImageNet-1k, though effect is smaller than spatial mixing initializations; can be combined with them for additional benefit.
Conclusion: First successful application of mimetic initialization to channel mixing layers demonstrates that simple weight initialization modifications can improve training efficiency for MLPs in vision tasks.
Abstract: Mimetic initialization uses pretrained models as case studies of good initialization, using observations of structures in trained weights to inspire new, simple initialization techniques. So far, it has been applied only to spatial mixing layers, such convolutional, self-attention, and state space layers. In this work, we present the first attempt to apply the method to channel mixing layers, namely multilayer perceptrons (MLPs). Our extremely simple technique for MLPs – to give the first layer a nonzero mean – speeds up training on small-scale vision tasks like CIFAR-10 and ImageNet-1k. Though its effect is much smaller than spatial mixing initializations, it can be used in conjunction with them for an additional positive effect.
[714] Learning Nonlinear Systems In-Context: From Synthetic Data to Real-World Motor Control
Tong Jian, Tianyu Dai, Tao Yu
Main category: cs.LG
TL;DR: Transformer-based in-context learning applied to motor feedforward control, enabling few-shot adaptation from synthetic pretraining to real-world motor systems
Details
Motivation: LLMs have strong in-context learning abilities but haven't been extended to signal processing systems. Classical PI controllers and physics-based methods struggle with nonlinearities and complex load conditions in motor control.Method: Propose transformer architecture that separates signal representation from system behavior, enabling few-shot finetuning and one-shot ICL. Pretrained on large corpus of synthetic linear and nonlinear systems, then adapted to real-world motors with few examples.
Result: Model generalizes across multiple motor load configurations, transforms untuned examples into accurate feedforward predictions, and outperforms PI controllers and physics-based feedforward baselines.
Conclusion: ICL can bridge synthetic pretraining and real-world adaptability, opening new directions for data-efficient control of physical systems.
Abstract: LLMs have shown strong in-context learning (ICL) abilities, but have not yet been extended to signal processing systems. Inspired by their design, we have proposed for the first time ICL using transformer models applicable to motor feedforward control, a critical task where classical PI and physics-based methods struggle with nonlinearities and complex load conditions. We propose a transformer based model architecture that separates signal representation from system behavior, enabling both few-shot finetuning and one-shot ICL. Pretrained on a large corpus of synthetic linear and nonlinear systems, the model learns to generalize to unseen system dynamics of real-world motors only with a handful of examples. In experiments, our approach generalizes across multiple motor load configurations, transforms untuned examples into accurate feedforward predictions, and outperforms PI controllers and physics-based feedforward baselines. These results demonstrate that ICL can bridge synthetic pretraining and real-world adaptability, opening new directions for data efficient control of physical systems.
[715] Latent Target Score Matching, with an application to Simulation-Based Inference
Joohwan Ko, Tomas Geffner
Main category: cs.LG
TL;DR: Latent Target Score Matching (LTSM) extends Target Score Matching to handle latent variables by leveraging joint scores for low-variance supervision of marginal scores in diffusion models.
Details
Motivation: Denoising Score Matching (DSM) suffers from high variance at low noise levels, and Target Score Matching (TSM) requires clean data scores which are often unavailable when latent variables are present, leaving only joint signals accessible.Method: Proposes Latent Target Score Matching (LTSM) that extends TSM to leverage joint scores for low-variance supervision of marginal scores. Uses a mixture of LTSM and DSM for robustness across noise scales.
Result: LTSM consistently improves variance, score accuracy, and sample quality across simulation-based inference tasks compared to baseline methods.
Conclusion: LTSM provides an effective solution for low-variance score matching when clean data scores are unavailable due to latent variables, improving diffusion model training.
Abstract: Denoising score matching (DSM) for training diffusion models may suffer from high variance at low noise levels. Target Score Matching (TSM) mitigates this when clean data scores are available, providing a low-variance objective. In many applications clean scores are inaccessible due to the presence of latent variables, leaving only joint signals exposed. We propose Latent Target Score Matching (LTSM), an extension of TSM to leverage joint scores for low-variance supervision of the marginal score. While LTSM is effective at low noise levels, a mixture with DSM ensures robustness across noise scales. Across simulation-based inference tasks, LTSM consistently improves variance, score accuracy, and sample quality.
[716] Systematic Performance Assessment of Deep Material Networks for Multiscale Material Modeling
Xiaolong He, Haoyan Wei, Wei Hu, Henan Mao, C. T. Wu
Main category: cs.LG
TL;DR: Deep Material Networks (DMNs) are mechanistic ML models for multiscale material modeling that can be trained on linear elastic data and generalize to nonlinear regimes, with this work providing comprehensive evaluation of their performance across training and prediction.
Details
Motivation: Despite growing adoption of DMNs for multiscale modeling of complex microstructures, there is limited systematic evaluation of their performance across the full offline-online pipeline, including prediction accuracy, computational efficiency, and training robustness.Method: Comprehensive comparative assessment of DMNs investigating effects of offline training choices (initialization, batch size, training data size, activation regularization) on online generalization performance and uncertainty. Also evaluates rotation-free Interaction-based Material Network (IMN) formulation.
Result: Prediction error and variance decrease with increasing training data size; initialization and batch size significantly influence model performance; activation regularization critically controls network complexity and generalization. IMN achieves 3.4x-4.7x speed-up in offline training while maintaining comparable online prediction accuracy.
Conclusion: The findings clarify key trade-offs between model expressivity and efficiency in structure-preserving material networks and provide practical guidance for their deployment in multiscale material modeling.
Abstract: Deep Material Networks (DMNs) are structure-preserving, mechanistic machine learning models that embed micromechanical principles into their architectures, enabling strong extrapolation capabilities and significant potential to accelerate multiscale modeling of complex microstructures. A key advantage of these models is that they can be trained exclusively on linear elastic data and then generalized to nonlinear inelastic regimes during online prediction. Despite their growing adoption, systematic evaluations of their performance across the full offline-online pipeline remain limited. This work presents a comprehensive comparative assessment of DMNs with respect to prediction accuracy, computational efficiency, and training robustness. We investigate the effects of offline training choices, including initialization, batch size, training data size, and activation regularization on online generalization performance and uncertainty. The results demonstrate that both prediction error and variance decrease with increasing training data size, while initialization and batch size can significantly influence model performance. Moreover, activation regularization is shown to play a critical role in controlling network complexity and therefore generalization performance. Compared with the original DMN, the rotation-free Interaction-based Material Network (IMN) formulation achieves a 3.4x - 4.7x speed-up in offline training, while maintaining comparable online prediction accuracy and computational efficiency. These findings clarify key trade-offs between model expressivity and efficiency in structure-preserving material networks and provide practical guidance for their deployment in multiscale material modeling.
[717] Risk-Sensitive Exponential Actor Critic
Alonso Granados, Jason Pacheco
Main category: cs.LG
TL;DR: Risk-sensitive reinforcement learning using entropic risk measure with stable policy gradient methods for continuous control tasks
Details
Motivation: Safety concerns in real-world RL applications require risk-aware agents, but current methods using entropic risk measure suffer from high-variance, numerically unstable updates, limiting them to simple tasksMethod: Proposes risk-sensitive exponential actor-critic (rsEAC), an off-policy model-free approach with novel procedures to avoid explicit representation of exponential value functions and their gradients, optimizing policy w.r.t entropic risk measure
Result: rsEAC produces more numerically stable updates compared to existing approaches and reliably learns risk-sensitive policies in challenging risky variants of continuous MuJoCo tasks
Conclusion: The paper provides comprehensive theoretical justification for policy gradient methods on entropic risk measure and demonstrates practical effectiveness through rsEAC for risk-sensitive RL in continuous control
Abstract: Model-free deep reinforcement learning (RL) algorithms have achieved tremendous success on a range of challenging tasks. However, safety concerns remain when these methods are deployed on real-world applications, necessitating risk-aware agents. A common utility for learning such risk-aware agents is the entropic risk measure, but current policy gradient methods optimizing this measure must perform high-variance and numerically unstable updates. As a result, existing risk-sensitive model-free approaches are limited to simple tasks and tabular settings. In this paper, we provide a comprehensive theoretical justification for policy gradient methods on the entropic risk measure, including on- and off-policy gradient theorems for the stochastic and deterministic policy settings. Motivated by theory, we propose risk-sensitive exponential actor-critic (rsEAC), an off-policy model-free approach that incorporates novel procedures to avoid the explicit representation of exponential value functions and their gradients, and optimizes its policy w.r.t the entropic risk measure. We show that rsEAC produces more numerically stable updates compared to existing approaches and reliably learns risk-sensitive policies in challenging risky variants of continuous tasks in MuJoCo.
[718] Exactly Computing do-Shapley Values
R. Teal Witter, Álvaro Parafita, Tomas Garriga, Maximilian Muschalik, Fabian Fumagalli, Axel Brando, Lucas Rosenblatt
Main category: cs.LG
TL;DR: A computational framework for efficiently computing do-Shapley values in Structural Causal Models by leveraging irreducible sets, with both exact linear-time algorithms and budgeted estimators that outperform prior methods.
Details
Motivation: Structural Causal Models (SCMs) are powerful for describing complex dynamics, but computing do-Shapley values (a game-theoretic method for quantifying variable effects) typically requires evaluating exponentially many interventions, making it computationally expensive. The authors aim to develop more efficient methods for computing these values.Method: The authors reformulate do-Shapley values in terms of irreducible sets of the underlying SCM. They develop an exact algorithm that computes do-Shapley values in time linear in the number of irreducible sets (r), which ranges from d to 2^d depending on graph structure. They also create estimators that work with any query budget, becoming more accurate as budget approaches r.
Result: The exact algorithm computes do-Shapley values in linear time relative to irreducible sets. The estimators produce more accurate estimates than prior methods by several orders of magnitude when query budget approaches r, and return exact Shapley values up to machine precision when budget reaches r. The method also reduces identification burden by requiring only singleton coalition interventions rather than all classes.
Conclusion: The paper presents efficient computational methods for do-Shapley values in SCMs, significantly reducing computational complexity and identification requirements while maintaining accuracy, making causal effect quantification more practical for complex systems.
Abstract: Structural Causal Models (SCM) are a powerful framework for describing complicated dynamics across the natural sciences. A particularly elegant way of interpreting SCMs is do-Shapley, a game-theoretic method of quantifying the average effect of $d$ variables across exponentially many interventions. Like Shapley values, computing do-Shapley values generally requires evaluating exponentially many terms. The foundation of our work is a reformulation of do-Shapley values in terms of the irreducible sets of the underlying SCM. Leveraging this insight, we can exactly compute do-Shapley values in time linear in the number of irreducible sets $r$, which itself can range from $d$ to $2^d$ depending on the graph structure of the SCM. Since $r$ is unknown a priori, we complement the exact algorithm with an estimator that, like general Shapley value estimators, can be run with any query budget. As the query budget approaches $r$, our estimators can produce more accurate estimates than prior methods by several orders of magnitude, and, when the budget reaches $r$, return the Shapley values up to machine precision. Beyond computational speed, we also reduce the identification burden: we prove that non-parametric identifiability of do-Shapley values requires only the identification of interventional effects for the $d$ singleton coalitions, rather than all classes.
[719] Online Learning for Uninformed Markov Games: Empirical Nash-Value Regret and Non-Stationarity Adaptation
Junyan Liu, Haipeng Luo, Zihan Zhang, Lillian J. Ratliff
Main category: cs.LG
TL;DR: New algorithm for online learning in uninformed Markov games achieves adaptive regret bounds that interpolate between O(√K) external regret for fixed opponents and O(K^{2/3}) Nash-value regret for worst-case opponents, using empirical Nash-value regret metric and adaptive restarting.
Details
Motivation: Previous work on uninformed Markov games had limitations: achieving no-external-regret required exponential dependence on episode length, and existing V-learning algorithms with Nash-value regret didn't adapt to problem difficulty, maintaining O(K^{2/3}) regret even when simpler O(√K) external regret was achievable for fixed opponents.Method: Introduces empirical Nash-value regret, a stronger metric that reduces to external regret for fixed opponents. Proposes parameter-free algorithm with adaptive restarting: first analyzes epoch-based V-learning to get O(ηC + √K/η) bound, then adaptively restarts with appropriate η in response to opponent’s non-stationarity.
Result: Achieves O(min{√K + (CK)^{1/3}, √LK}) regret bound, where C quantifies opponent policy variance and L denotes number of policy switches. This recovers both extremes (O(√K) for fixed opponents and O(K^{2/3}) worst-case) and smoothly interpolates between them by adapting to opponent non-stationarity.
Conclusion: The work fully addresses limitations of previous approaches by introducing a stronger regret metric and adaptive algorithm that automatically adjusts to opponent behavior, providing optimal regret guarantees across different opponent scenarios in uninformed Markov games.
Abstract: We study online learning in two-player uninformed Markov games, where the opponent’s actions and policies are unobserved. In this setting, Tian et al. (2021) show that achieving no-external-regret is impossible without incurring an exponential dependence on the episode length $H$. They then turn to the weaker notion of Nash-value regret and propose a V-learning algorithm with regret $O(K^{2/3})$ after $K$ episodes. However, their algorithm and guarantee do not adapt to the difficulty of the problem: even in the case where the opponent follows a fixed policy and thus $O(\sqrt{K})$ external regret is well-known to be achievable, their result is still the worse rate $O(K^{2/3})$ on a weaker metric. In this work, we fully address both limitations. First, we introduce empirical Nash-value regret, a new regret notion that is strictly stronger than Nash-value regret and naturally reduces to external regret when the opponent follows a fixed policy. Moreover, under this new metric, we propose a parameter-free algorithm that achieves an $O(\min {\sqrt{K} + (CK)^{1/3},\sqrt{LK}})$ regret bound, where $C$ quantifies the variance of the opponent’s policies and $L$ denotes the number of policy switches (both at most $O(K)$). Therefore, our results not only recover the two extremes – $O(\sqrt{K})$ external regret when the opponent is fixed and $O(K^{2/3})$ Nash-value regret in the worst case – but also smoothly interpolate between these extremes by automatically adapting to the opponent’s non-stationarity. We achieve so by first providing a new analysis of the epoch-based V-learning algorithm by Mao et al. (2022), establishing an $O(ηC + \sqrt{K/η})$ regret bound, where $η$ is the epoch incremental factor. Next, we show how to adaptively restart this algorithm with an appropriate $η$ in response to the potential non-stationarity of the opponent, eventually achieving our final results.
[720] DSL: Understanding and Improving Softmax Recommender Systems with Competition-Aware Scaling
Bucher Sahyouni, Matthew Vowels, Liqun Chen, Simon Hadfield
Main category: cs.LG
TL;DR: DSL introduces a dual-scale softmax loss for recommender systems that adapts loss sharpness based on sampled competition, improving performance and robustness over standard softmax loss.
Details
Motivation: Standard softmax loss in implicit-feedback recommender systems uses a single global temperature and treats uniformly sampled negatives equally, which can lead to brittle training since sampled sets contain varying degrees of relevant/informative competitors. Optimal loss sharpness for one user-item pair may be suboptimal or destabilizing for another with different negatives.Method: Dual-scale Softmax Loss (DSL) adds two complementary branches to the log-sum-exp backbone: 1) reweights negatives within each training instance using hardness and item-item similarity, 2) adapts a per-example temperature from the competition intensity over a constructed competitor slate. This preserves SL geometry while reshaping competition distribution across negatives and examples.
Result: DSL yields substantial gains over strong baselines, with improvements over standard softmax loss exceeding 10% in several settings and averaging 6.22% across datasets, metrics, and backbones. Under out-of-distribution popularity shift, gains are larger with average 9.31% improvement over SL.
Conclusion: DSL effectively infers loss sharpness from sampled competition itself, improving recommender system performance and robustness. Theoretical DRO analysis shows how DSL reshapes robust payoff and KL deviation for ambiguous instances, explaining observed accuracy and robustness improvements.
Abstract: Softmax Loss (SL) is being increasingly adopted for recommender systems (RS) as it has demonstrated better performance, robustness and fairness. Yet in implicit-feedback, a single global temperature and equal treatment of uniformly sampled negatives can lead to brittle training, because sampled sets may contain varying degrees of relevant or informative competitors. The optimal loss sharpness for a user-item pair with a particular set of negatives, can be suboptimal or destabilising for another with different negatives. We introduce Dual-scale Softmax Loss (DSL), which infers effective sharpness from the sampled competition itself. DSL adds two complementary branches to the log-sum-exp backbone. Firstly it reweights negatives within each training instance using hardness and item–item similarity, secondly it adapts a per-example temperature from the competition intensity over a constructed competitor slate. Together, these components preserve the geometry of SL while reshaping the competition distribution across negatives and across examples. Over several representative benchmarks and backbones, DSL yields substantial gains over strong baselines, with improvements over SL exceeding $10%$ in several settings and averaging $6.22%$ across datasets, metrics, and backbones. Under out-of-distribution (OOD) popularity shift, the gains are larger, with an average of $9.31%$ improvement over SL. We further provide a theoretical, distributionally robust optimisation (DRO) analysis, which demonstrates how DSL reshapes the robust payoff and the KL deviation for ambiguous instances. This helps explain the empirically observed improvements in accuracy and robustness.
[721] Adaptive Retrieval helps Reasoning in LLMs – but mostly if it’s not used
Srijan Shakya, Anamaria-Roberta Hartl, Sepp Hochreiter, Korbinian Pöppel
Main category: cs.LG
TL;DR: Adaptive retrieval-augmented LLM architecture where model decides when to query external knowledge during reasoning, showing retrieval rarely helps but selective non-retrieval indicates better performance.
Details
Motivation: LLMs struggle with complex reasoning due to static parametric knowledge, leading to hallucinations and poor performance in specialized domains like mathematics. The paper explores enhancing generative models through dynamic in-context learning via retrieval.Method: Tests adaptive retrieval-augmented architecture where LLM agent actively decides when to query external knowledge base during reasoning. Compares adaptive strategy against standard Chain-of-Thought baseline and static retrieval on GSM8K and MATH-500 benchmarks.
Result: Static retrieval inferior to CoT. Adaptive retrieval shows interesting behavior: traces with retrieval perform slightly worse than CoT, but traces without retrieval actually perform better. Retrieval rarely helps reasoning (few counterexamples like using theorems). Actively not using retrieval indicates good model performance. Model scales retrieval frequency with problem difficulty.
Conclusion: The decision to retrieve is a crucial metacognitive signal. Agent’s ability to self-assess knowledge and selectively engage with external information represents key principle for building more robust and reliable generative models.
Abstract: Large Language Models (LLMs) often falter in complex reasoning tasks due to their static, parametric knowledge, leading to hallucinations and poor performance in specialized domains like mathematics. This work explores a fundamental principle for enhancing generative models: treating retrieval as a form of dynamic in-context learning. We test an adaptive retrieval-augmented architecture where an LLM agent actively decides when to query an external knowledge base during its reasoning process. We compare this adaptive strategy against a standard Chain-of-Thought (CoT) baseline and a static retrieval approach on the GSM8K and MATH-500 benchmarks. Although our experiments show that static retrieval is inferior to CoT, the adaptive retrieval shows interesting behavior: While traces including retrieved results show slightly worse performance compared to CoT, traces that do not include retrieval actually perform better compared to CoT. This suggests that: (a) retrieval only rarely helps reasoning (we show a few counterexamples, e.g. using useful theorems) and (b) actively not using retrieval is indicative of good model performance. Furthermore, we find that the model scales its retrieval frequency with the difficulty of the problem, reinforcing that the decision to retrieve is a crucial metacognitive signal. The agent’s ability to self-assess its knowledge and selectively engage with external information represents a key principle for building more robust and reliable generative models.
[722] Probing Neural TSP Representations for Prescriptive Decision Support
Reuben Narad, Léonard Boussioux, Michael Wagner
Main category: cs.LG
TL;DR: Trained neural TSP solvers learn transferable representations useful for downstream prescriptive tasks like identifying critical nodes/edges, with probes outperforming baselines and transferability improving with solver quality.
Details
Motivation: To investigate whether neural combinatorial optimization (NCO) models trained for TSP learn internal representations that transfer to other optimization-relevant downstream tasks, moving beyond just producing good tours to enable prescriptive decision-support.Method: Train attention-based TSP policies, collect internal activations, and train probes on node/edge embeddings for two NP-hard downstream tasks: node-removal sensitivity (identifying most impactful node to remove) and edge-forbid sensitivity (identifying most critical edge to retain).
Result: Probes for both tasks are competitive with existing baselines. Ensembling probe signals with geometric features outperforms strongest baselines: 65% top-1 accuracy (vs. 58% baseline) for best-node-removal, and 73% top-1 accuracy (vs. 67% baseline) for worst-edge identification.
Conclusion: Neural TSP solvers can serve as transferable encoders for prescriptive what-if decision-support objectives beyond tour construction, with transfer accuracy increasing with solver quality and model scale.
Abstract: The field of neural combinatorial optimization (NCO) trains neural policies to solve NP-hard problems such as the traveling salesperson problem (TSP). We ask whether, beyond producing good tours, a trained TSP solver learns internal representations that transfer to other optimization-relevant objectives, in the spirit of transfer learning from other domains. We train several attention-based TSP policies, collect their internal activations, and train probes on node/edge embeddings for two NP-hard prescriptive downstream tasks inspired by real-world logistics scenarios: node-removal sensitivity (identifying the most impactful node to remove) and edge-forbid sensitivity (identifying the most critical edge to retain). On a Euclidean TSP100-trained model, probes for both tasks are competitive with existing baselines. Ensembling probe signals with geometric features outperforms the strongest baselines: 65% top-1 accuracy (vs. 58% baseline) for the best-node-removal task, and 73% top-1 accuracy (vs. 67% baseline) for the worst-edge identification task. To our knowledge, we are the first to study neural TSP solvers as transferable encoders for prescriptive what-if decision-support objectives beyond tour construction. Finally, we show that transfer accuracy increases with solver quality across training and model scale, suggesting that training stronger NCO solvers also yields more useful encoders for downstream objectives. Our code is available at: github.com/ReubenNarad/tsp_prescriptive_probe
[723] Collaborative and Efficient Fine-tuning: Leveraging Task Similarity
Gagik Magakyan, Amirhossein Reisizadeh, Chanwoo Park, Pablo A. Parrilo, Asuman Ozdaglar
Main category: cs.LG
TL;DR: CoLoRA enables collaborative parameter-efficient fine-tuning of foundation models by leveraging task similarity across multiple users, using shared adapters for common patterns and personalized adapters for user-specific tasks.
Details
Motivation: To address data scarcity in fine-tuning foundation models by exploiting task similarity across multiple downstream users, allowing them to assist each other in boosting effective fine-tuning data size.Method: Proposes Collaborative Low-Rank Adaptation (CoLoRA) with two components: 1) a shared adapter capturing underlying task similarities across all tasks, and 2) personalized adapters tailored to user-specific tasks.
Result: Theoretical analysis on heterogeneous linear regression provides provable guarantees for ground truth recovery. Natural language experiments show significant performance boosts when models are trained together with similar tasks.
Conclusion: CoLoRA effectively leverages task similarity for collaborative fine-tuning, addressing data scarcity while maintaining parameter efficiency through the LoRA framework.
Abstract: Adaptability has been regarded as a central feature in the foundation models, enabling them to effectively acclimate to unseen downstream tasks. Parameter-efficient fine-tuning methods such as celebrated LoRA facilitate efficient adaptation of large foundation models using labeled, high-quality and generally scarce task data. To mitigate data scarcity in fine-tuning of foundation models, we propose to leverage task similarity across multiple downstream users. Intuitively, users with similar tasks must be able to assist each other in boosting the effective fine-tuning data size. We propose Collaborative Low-Rank Adaptation, or CoLoRA, which exploits task similarity to collaboratively and efficiently fine-tune personalized foundation models. The main idea in CoLoRA is to train one shared adapter capturing underlying task similarities across all tasks, and personalized adapters tailored to user-specific tasks. We theoretically study CoLoRA on heterogeneous linear regression and provide provable guarantees for ground truth recovery. We also conduct several natural language experiments with varying task similarity, which further demonstrate that when trained together with similar tasks, individual performances are significantly boosted.
[724] The Median is Easier than it Looks: Approximation with a Constant-Depth, Linear-Width ReLU Network
Abhigyan Dutta, Itay Safran, Paul Valiant
Main category: cs.LG
TL;DR: Neural networks can approximate the median function with constant depth and linear width, achieving exponentially small error, which breaks prior barriers suggested for maximum function approximation.
Details
Motivation: The paper investigates the approximation capabilities of ReLU neural networks for computing the median of multiple inputs. There's interest in understanding depth-width tradeoffs for fundamental statistical functions like median, especially since prior work on the maximum function suggested limitations that this work aims to overcome.Method: The authors present a multi-stage procedure that iteratively eliminates non-central elements while preserving a candidate set around the median. They establish a general reduction from the maximum to the median function, allowing them to leverage their median approximation results to achieve stronger bounds than previously known for maximum approximation.
Result: The construction achieves constant-depth, linear-width neural networks that can approximate the median with exponentially small error with respect to the uniform distribution over the unit hypercube. This breaks the barrier suggested by prior work on the maximum function, which indicated that linear width would require depth growing at least as log log d for comparable accuracy.
Conclusion: ReLU neural networks can approximate the median function more efficiently than previously thought possible, with constant depth and linear width achieving exponentially small error. The results demonstrate that median approximation is strictly stronger than maximum approximation in this context, overcoming obstacles that don’t arise for the maximum function.
Abstract: We study the approximation of the median of $d$ inputs using ReLU neural networks. We present depth-width tradeoffs under several settings, culminating in a constant-depth, linear-width construction that achieves exponentially small approximation error with respect to the uniform distribution over the unit hypercube. By further establishing a general reduction from the maximum to the median, our results break a barrier suggested by prior work on the maximum function, which indicated that linear width should require depth growing at least as $\log\log d$ to achieve comparable accuracy. Our construction relies on a multi-stage procedure that iteratively eliminates non-central elements while preserving a candidate set around the median. We overcome obstacles that do not arise for the maximum to yield approximation results that are strictly stronger than those previously known for the maximum itself.
[725] SpecAttn: Co-Designing Sparse Attention with Self-Speculative Decoding
Yikang Yue, Yuqi Xue, Jian Huang
Main category: cs.LG
TL;DR: SpecAttn is a self-speculative decoding method that uses verification-guided sparse attention to reduce KV cache memory demands and improve LLM inference throughput.
Details
Motivation: Long-context LLM inference is bottlenecked by increasing memory demands of KV cache. Existing self-speculative decoding methods with sparse attention rely on standalone KV selection algorithms and overlook that criticality of KV entries is computed during verification.Method: Proposes SpecAttn, which identifies critical KV entries as a byproduct of verification and only loads these entries when drafting subsequent tokens. This verification-guided sparse attention improves draft token acceptance rate with low KV selection overhead.
Result: Achieves 2.81× higher throughput over vanilla auto-regressive decoding and 1.29× improvement over state-of-the-art sparsity-based self-speculative decoding methods.
Conclusion: SpecAttn effectively reduces KV cache memory demands while improving decoding throughput through verification-guided sparse attention, making it a practical solution for efficient long-context LLM inference.
Abstract: Long-context large language model (LLM) inference has become the norm for today’s AI applications. However, it is severely bottlenecked by the increasing memory demands of its KV cache. Previous works have shown that self-speculative decoding with sparse attention, where tokens are drafted using a subset of the KV cache and verified in parallel with full KV cache, speeds up inference in a lossless way. However, this approach relies on standalone KV selection algorithms to select the KV entries used for drafting and overlooks that the criticality of each KV entry is inherently computed during verification. In this paper, we propose SpecAttn, a self-speculative decoding method with verification-guided sparse attention. SpecAttn identifies critical KV entries as a byproduct of verification and only loads these entries when drafting subsequent tokens. This not only improves draft token acceptance rate but also incurs low KV selection overhead, thereby improving decoding throughput. SpecAttn achieves 2.81$\times$ higher throughput over vanilla auto-regressive decoding and 1.29$\times$ improvement over state-of-the-art sparsity-based self-speculative decoding methods.
[726] RiskAgent: Synergizing Language Models with Validated Tools for Evidence-Based Risk Prediction
Fenglin Liu, Jinge Wu, Hongjian Zhou, Xiao Gu, Jiayuan Zhu, Jiazhen Pan, Junde Wu, Soheila Molaei, Anshul Thakur, Lei Clifton, Honghan Wu, David A. Clifton
Main category: cs.LG
TL;DR: RiskAgent combines LLMs with clinical decision tools for medical risk prediction, achieving superior performance across diverse clinical scenarios while reducing hallucinations.
Details
Motivation: LLMs perform well on medical exams but struggle with complex clinical decision-making that requires deep medical knowledge. Fine-tuning LLMs for clinical tasks requires substantial resources and still suffers from hallucinations. There's a need for a more reliable, evidence-based approach to clinical decision support.Method: RiskAgent synergizes language models with hundreds of validated clinical decision tools supported by evidence-based medicine. The system integrates these tools to provide generalizable and faithful recommendations rather than relying solely on LLM-generated responses.
Result: RiskAgent achieves superior performance on broad clinical risk predictions across diverse scenarios and diseases. It demonstrates robust generalization in tool learning on MedCalc-Bench, and performs well on medical reasoning benchmarks including MedQA, MedMCQA, and MMLU.
Conclusion: Integrating LLMs with evidence-based clinical decision tools provides a more reliable approach to clinical risk prediction and decision support, reducing hallucinations while maintaining strong performance across multiple medical benchmarks.
Abstract: Large Language Models (LLMs) achieve competitive results compared to human experts in medical examinations. However, it remains a challenge to apply LLMs to complex clinical decision-making, which requires a deep understanding of medical knowledge and differs from the standardized, exam-style scenarios commonly used in current efforts. A common approach is to fine-tune LLMs for target tasks, which, however, not only requires substantial data and computational resources but also remains prone to generating `hallucinations’. In this work, we present RiskAgent, which synergizes language models with hundreds of validated clinical decision tools supported by evidence-based medicine, to provide generalizable and faithful recommendations. Our experiments show that RiskAgent not only achieves superior performance on a broad range of clinical risk predictions across diverse scenarios and diseases, but also demonstrates robust generalization in tool learning on the external MedCalc-Bench dataset, as well as in medical reasoning and question answering on three representative benchmarks, MedQA, MedMCQA, and MMLU.
[727] Fault-Tolerant Evaluation for Sample-Efficient Model Performance Estimators
Zihan Zhu, Yanqiu Wu, Qiongkai Xu
Main category: cs.LG
TL;DR: Proposes a fault-tolerant evaluation framework for sample-efficient performance estimators in Model-as-a-Service scenarios, addressing limitations of existing methods in low-variance settings.
Details
Motivation: In Model-as-a-Service environments, efficient validation of third-party AI models is challenging due to dynamic applications, new datasets, and many competing models. Existing evaluation approaches fail in low-variance settings: RMSE conflates bias and variance, while p-value tests become hypersensitive to negligible deviations.Method: Proposes a fault-tolerant evaluation framework that integrates bias and variance considerations within an adjustable tolerance level ε. The framework enables evaluation of performance estimators within practically acceptable error margins. Theoretically shows proper calibration of ε ensures reliable evaluation across variance regimes, and proposes an algorithm that automatically optimizes and selects ε.
Result: Experiments on real-world datasets demonstrate that the framework provides comprehensive and actionable insights into estimator behavior, addressing limitations of existing evaluation methods.
Conclusion: The proposed fault-tolerant evaluation framework effectively addresses the challenges of evaluating performance estimators in Model-as-a-Service scenarios, particularly in low-variance settings where traditional methods fail.
Abstract: In the era of Model-as-a-Service, organizations increasingly rely on third-party AI models for rapid deployment. However, the dynamic nature of emerging AI applications, the continual introduction of new datasets, and the growing number of models claiming superior performance make efficient and reliable validation of model services increasingly challenging. This motivates the development of sample-efficient performance estimators, which aim to estimate model performance by strategically selecting instances for labeling, thereby reducing annotation cost. Yet existing evaluation approaches often fail in low-variance settings: RMSE conflates bias and variance, masking persistent bias when variance is small, while p-value based tests become hypersensitive, rejecting adequate estimators for negligible deviations. To address this, we propose a fault-tolerant evaluation framework that integrates bias and variance considerations within an adjustable tolerance level ${\varepsilon}$, enabling the evaluation of performance estimators within practically acceptable error margins. We theoretically show that proper calibration of ${\varepsilon}$ ensures reliable evaluation across different variance regimes, and we further propose an algorithm that automatically optimizes and selects ${\varepsilon}$. Experiments on real-world datasets demonstrate that our framework provides comprehensive and actionable insights into estimator behavior.
[728] Spatiotemporal Attention-Augmented Inverse Reinforcement Learning for Multi-Agent Task Allocation
Huilin Yin, Zhikun Yang, Linchuan Zhang, Daniel Watzenig
Main category: cs.LG
TL;DR: Attention-structured adversarial IRL framework for multi-agent task allocation using MHSA and GAT for stable reward inference
Details
Motivation: Adversarial IRL for multi-agent task allocation faces challenges with non-stationary interactions and high-dimensional coordination, leading to high variance and poor generalization in unconstrained reward inference.Method: Proposes attention-structured adversarial IRL framework using multi-head self-attention (MHSA) for temporal dependencies and graph attention networks (GAT) for agent-task relational structures. Formulates reward inference as low-capacity adaptive linear transformation of environment reward.
Result: Outperforms representative MARL baselines in convergence speed, cumulative rewards, and spatial efficiency on benchmark MATA scenarios.
Conclusion: Attention-guided, capacity-constrained reward inference is a scalable and effective mechanism for stabilizing adversarial IRL in complex multi-agent systems.
Abstract: Adversarial inverse reinforcement learning (IRL) for multi-agent task allocation (MATA) is challenged by non-stationary interactions and high-dimensional coordination. Unconstrained reward inference in these settings often leads to high variance and poor generalization. We propose an attention-structured adversarial IRL framework that constrains reward inference via spatiotemporal representation learning. Our method employs multi-head self-attention (MHSA) for long-range temporal dependencies and graph attention networks (GAT) for agent-task relational structures. We formulate reward inference as a low-capacity, adaptive linear transformation of the environment reward, ensuring stable and interpretable guidance. This framework decouples reward inference from policy learning and optimizes the reward model adversarially. Experiments on benchmark MATA scenarios show that our approach outperforms representative MARL baselines in convergence speed, cumulative rewards, and spatial efficiency. Results demonstrate that attention-guided, capacity-constrained reward inference is a scalable and effective mechanism for stabilizing adversarial IRL in complex multi-agent systems.
[729] Cerebellar-Inspired Residual Control for Fault Recovery: From Inference-Time Adaptation to Structural Consolidation
Nethmi Jayasinghe, Diana Gontero, Spencer T. Brown, Vinod K. Sangwan, Mark C. Hersam, Amit Ranjan Trivedi
Main category: cs.LG
TL;DR: Cerebellar-inspired residual control framework that augments frozen RL policies with online corrective actions for fault recovery without modifying base policy parameters.
Details
Motivation: Robotic policies deployed in real-world environments often encounter post-training faults where retraining, exploration, or system identification are impractical, requiring inference-time adaptation without destabilizing the base policy.Method: Inference-time cerebellar-inspired residual control framework with: 1) high-dimensional pattern separation via fixed feature expansion, 2) parallel microzone-style residual pathways, 3) local error-driven plasticity with excitatory/inhibitory eligibility traces at distinct time scales, and 4) conservative meta-adaptation regulating residual authority and plasticity.
Result: Improvements of up to +66% on HalfCheetah-v5 and +53% on Humanoid-v5 under moderate faults, with graceful degradation under severe shifts and complementary robustness from consolidating persistent residual corrections into policy parameters.
Conclusion: The cerebellar-inspired framework enables effective fault recovery for frozen RL policies through localized, online corrective actions while preserving nominal behavior, offering a practical solution for real-world robotic deployment.
Abstract: Robotic policies deployed in real-world environments often encounter post-training faults, where retraining, exploration, or system identification are impractical. We introduce an inference-time, cerebellar-inspired residual control framework that augments a frozen reinforcement learning policy with online corrective actions, enabling fault recovery without modifying base policy parameters. The framework instantiates core cerebellar principles, including high-dimensional pattern separation via fixed feature expansion, parallel microzone-style residual pathways, and local error-driven plasticity with excitatory and inhibitory eligibility traces operating at distinct time scales. These mechanisms enable fast, localized correction under post-training disturbances while avoiding destabilizing global policy updates. A conservative, performance-driven meta-adaptation regulates residual authority and plasticity, preserving nominal behavior and suppressing unnecessary intervention. Experiments on MuJoCo benchmarks under actuator, dynamic, and environmental perturbations show improvements of up to $+66%$ on \texttt{HalfCheetah-v5} and $+53%$ on \texttt{Humanoid-v5} under moderate faults, with graceful degradation under severe shifts and complementary robustness from consolidating persistent residual corrections into policy parameters.
[730] ArcMark: Multi-bit LLM Watermark via Optimal Transport
Atefeh Gilani, Carol Xuan Long, Sajani Vithana, Oliver Kosut, Lalitha Sankar, Flavio P. Calmon
Main category: cs.LG
TL;DR: ArcMark: A capacity-achieving multi-bit watermark for language models based on coding theory principles
Details
Motivation: Existing multi-bit watermarks for language models extend principles from zero-bit watermarks and encode only one bit per token, leaving the information-theoretic capacity of multi-bit watermarking unknown.Method: Derived the first capacity characterization of multi-bit watermarks, then designed ArcMark based on coding-theoretic principles to achieve this capacity under certain assumptions.
Result: ArcMark outperforms competing multi-bit watermarks in bit rate per token and detection accuracy, demonstrating that LM watermarking is fundamentally a channel coding problem.
Conclusion: The work establishes the theoretical foundations for multi-bit watermarking capacity and provides a principled coding-theoretic approach to watermark design for language models.
Abstract: Watermarking is an important tool for promoting the responsible use of language models (LMs). Existing watermarks insert a signal into generated tokens that either flags LM-generated text (zero-bit watermarking) or encodes more complex messages (multi-bit watermarking). Though a number of recent multi-bit watermarks insert several bits into text without perturbing average next-token predictions, they largely extend design principles from the zero-bit setting, such as encoding a single bit per token. Notably, the information-theoretic capacity of multi-bit watermarking – the maximum number of bits per token that can be inserted and detected without changing average next-token predictions – has remained unknown. We address this gap by deriving the first capacity characterization of multi-bit watermarks. Our results inform the design of ArcMark: a new watermark construction based on coding-theoretic principles that, under certain assumptions, achieves the capacity of the multi-bit watermark channel. In practice, ArcMark outperforms competing multi-bit watermarks in terms of bit rate per token and detection accuracy. Our work demonstrates that LM watermarking is fundamentally a channel coding problem, paving the way for principled coding-theoretic approaches to watermark design.
[731] Graph homophily booster: Reimagining the role of discrete features in heterophilic graph learning
Ruizhong Qiu, Ting-Wei Li, Gaotang Li, Hanghang Tong
Main category: cs.LG
TL;DR: GRAPHITE is a novel framework that addresses graph heterophily by directly transforming graphs to increase homophily through feature node creation, enabling better message passing between similar nodes.
Details
Motivation: Existing GNNs struggle with heterophilic graphs where connected nodes have dissimilar features/labels. Current methods focus on architectural designs but still perform worse than simple MLPs on challenging heterophilic datasets, calling for a new approach that directly addresses the root cause of heterophily.Method: GRAPHITE transforms graphs to directly improve homophily by creating feature nodes that facilitate homophilic message passing between nodes sharing similar features. This approach stems from the exact definition of homophily and only slightly increases graph size.
Result: Extensive experiments show GRAPHITE significantly outperforms state-of-the-art methods on heterophilic graphs while achieving comparable accuracy on homophilic graphs. The method theoretically and empirically demonstrates significant homophily increase for originally heterophilic graphs.
Conclusion: GRAPHITE presents a new paradigm for addressing graph heterophily by directly transforming graph structure rather than focusing solely on architectural designs, offering a simple yet effective solution to a critical challenge in graph learning.
Abstract: Graph neural networks (GNNs) have emerged as a powerful tool for modeling graph-structured data. However, existing GNNs often struggle with heterophilic graphs, where connected nodes tend to have dissimilar features or labels. While numerous methods have been proposed to address this challenge, they primarily focus on architectural designs without directly targeting the root cause of the heterophily problem. These approaches still perform even worse than the simplest MLPs on challenging heterophilic datasets. For instance, our experiments show that 21 latest GNNs still fall behind the MLP on the Actor dataset. This critical challenge calls for an innovative approach to addressing graph heterophily beyond architectural designs. To bridge this gap, we propose and study a new and unexplored paradigm: directly increasing the graph homophily via a carefully designed graph transformation. In this work, we present a simple yet effective framework called GRAPHITE to address graph heterophily. To the best of our knowledge, this work is the first method that explicitly transforms the graph to directly improve the graph homophily. Stemmed from the exact definition of homophily, our proposed GRAPHITE creates feature nodes to facilitate homophilic message passing between nodes that share similar features. Furthermore, we both theoretically and empirically show that our proposed GRAPHITE significantly increases the homophily of originally heterophilic graphs, with only a slight increase in the graph size. Extensive experiments on challenging datasets demonstrate that our proposed GRAPHITE significantly outperforms state-of-the-art methods on heterophilic graphs while achieving comparable accuracy with state-of-the-art methods on homophilic graphs.
[732] Robust Ultra-High-Dimensional Variable Selection With Correlated Structure Using Group Testing
Wanru Guo, Juan Xie, Binbin Wang, Weicong Chen, Xiaoyi Lu, Vipin Chaudhary, Curtis Tatsuoka
Main category: cs.LG
TL;DR: A robust feature selection framework for high-dimensional genomic data using multi-stage clustering and hypothesis testing with robust variants for contaminated data.
Details
Motivation: High-dimensional genomic data have strong group correlation structures that challenge conventional feature selection methods, which often assume feature independence, rely on pre-defined pathways, and are sensitive to outliers and model misspecification.Method: Dorfman screening framework: multi-stage procedure that forms data-driven variable groups via hierarchical clustering, performs group and within-group hypothesis testing, and refines selection using elastic net or adaptive elastic net. Robust variants incorporate OGK-based covariance estimation, rank-based correlation, and Huber-weighted regression.
Result: In simulations, Dorfman-Sparse-Adaptive-EN performed best under normal conditions, while Robust-OGK-Dorfman-Adaptive-EN showed clear advantages under data contamination, outperforming classical Dorfman and competing methods. Applied to NSCLC gene expression data, robust Dorfman methods achieved lowest prediction errors and enriched recovery of clinically relevant genes.
Conclusion: The Dorfman framework provides efficient and robust genomic feature selection. Robust-OGK-Dorfman-Adaptive-EN offers strong performance under both ideal and contaminated conditions and scales to ultra-high-dimensional settings, making it well suited for modern genomic biomarker discovery.
Abstract: Background: High-dimensional genomic data exhibit strong group correlation structures that challenge conventional feature selection methods, which often assume feature independence or rely on pre-defined pathways and are sensitive to outliers and model misspecification. Methods: We propose the Dorfman screening framework, a multi-stage procedure that forms data-driven variable groups via hierarchical clustering, performs group and within-group hypothesis testing, and refines selection using elastic net or adaptive elastic net. Robust variants incorporate OGK-based covariance estimation, rank-based correlation, and Huber-weighted regression to handle contaminated and non-normal data. Results: In simulations, Dorfman-Sparse-Adaptive-EN performed best under normal conditions, while Robust-OGK-Dorfman-Adaptive-EN showed clear advantages under data contamination, outperforming classical Dorfman and competing methods. Applied to NSCLC gene expression data for trametinib response, robust Dorfman methods achieved the lowest prediction errors and enriched recovery of clinically relevant genes. Conclusions: The Dorfman framework provides an efficient and robust approach to genomic feature selection. Robust-OGK-Dorfman-Adaptive-EN offers strong performance under both ideal and contaminated conditions and scales to ultra-high-dimensional settings, making it well suited for modern genomic biomarker discovery.
[733] tLoRA: Efficient Multi-LoRA Training with Elastic Shared Super-Models
Kevin Li, Dibyadeep Saha, Avni Kanodia, Fan Lai
Main category: cs.LG
TL;DR: tLoRA enables efficient batch training of multiple LoRA fine-tuning jobs by fusing adapters into a shared super-model with adaptive scheduling and fused kernels.
Details
Motivation: As LoRA becomes standard for fine-tuning LLMs, shared clusters run many concurrent LoRA jobs over the same backbone. Current approaches struggle with heterogeneous adapters (different ranks, batch sizes) causing synchronization stalls, communication overhead, and slowdowns worse than independent execution.Method: tLoRA fuses adapters sharing the same base model into an elastic shared super-model, using distributed training frameworks for parallelism. At kernel level: fused LoRA kernel adaptively reconstructs low-rank computation tiles and schedules rank-aware nano-batches. At scheduling layer: online, residual-capacity-aware scheduler adaptively groups jobs to maximize throughput.
Result: Evaluations with real-world cluster traces show tLoRA improves training throughput by 1.2-1.8x, job training completion time by 2.3-5.4x, and GPU utilization by 37%.
Conclusion: tLoRA provides an efficient framework for batch training multiple LoRA jobs, addressing the challenges of heterogeneous adapter co-location in shared clusters.
Abstract: As Low-Rank Adaptation (LoRA) becomes the standard approach for efficiently fine-tuning large language models (LLMs), shared clusters increasingly execute many concurrent LoRA training jobs over the same frozen backbone. While recent advances enable batching (co-locating) multiple adapters during serving, efficient training-time co-location of heterogeneous LoRA adapters presents unique challenges. Jobs often differ in adapter rank, batch size, and resource allocation, and naïve batching can introduce synchronization stalls, communication overheads, and per-job slowdowns that are worse than executing independently. We introduce tLoRA, a framework that enables efficient batch training of multiple LoRA jobs. tLoRA fuses adapters that share the same base model into an elastic shared super-model, exploiting existing distributed training frameworks to derive parallelism plans that share resources effectively. At the kernel level, tLoRA employs a fused LoRA kernel that adaptively reconstructs low-rank computation tiles and schedules rank-aware nano-batches to maximize overlap between computation and communication across adapters. At the scheduling layer, tLoRA incorporates an online, residual-capacity-aware scheduler that adaptively groups jobs to maximize collective throughput. Evaluations using real-world cluster traces demonstrate that tLoRA improves training throughput by 1.2–1.8x, job training completion time by 2.3–5.4x, and GPU utilization by 37%.
[734] XShare: Collaborative in-Batch Expert Sharing for Faster MoE Inference
Daniil Vankov, Nikita Ivkin, Kyle Ulrich, Xiang Song, Ashish Khetan, George Karypis
Main category: cs.LG
TL;DR: XShare: A method for batch-aware expert selection in Mixture-of-Experts models that reduces expert activation by up to 30% and improves throughput by up to 14% without retraining.
Details
Motivation: Production inference with request batching and speculative decoding significantly increases expert activation in MoE models, eroding their efficiency benefits. Current approaches don't optimize expert selection at batch level.Method: Models batch-aware expert selection as modular optimization problem, designs efficient greedy algorithms for different deployment settings. Uses XShare to dynamically adapt to each batch by maximizing total gating score of selected experts.
Result: Reduces expert activation by up to 30% under standard batching, cuts peak GPU load by up to 3x in expert-parallel deployments, achieves up to 14% throughput gains in speculative decoding via hierarchical, correlation-aware expert selection.
Conclusion: XShare effectively addresses efficiency erosion in MoE production inference through batch-aware expert selection, requiring no retraining and working with heterogeneous datasets.
Abstract: Mixture-of-Experts (MoE) architectures are increasingly used to efficiently scale large language models. However, in production inference, request batching and speculative decoding significantly amplify expert activation, eroding these efficiency benefits. We address this issue by modeling batch-aware expert selection as a modular optimization problem and designing efficient greedy algorithms for different deployment settings. The proposed method, namely XShare, requires no retraining and dynamically adapts to each batch by maximizing the total gating score of selected experts. It reduces expert activation by up to 30% under standard batching, cuts peak GPU load by up to 3x in expert-parallel deployments, and achieves up to 14% throughput gains in speculative decoding via hierarchical, correlation-aware expert selection even if requests in a batch drawn from heterogeneous datasets.
[735] Laplacian-LoRA: Delaying Oversmoothing in Deep GCNs via Spectral Low-Rank Adaptation
Sai Vamsi Alisetti
Main category: cs.LG
TL;DR: Laplacian-LoRA introduces a learnable low-rank spectral adaptation to the graph Laplacian operator in GCNs to delay oversmoothing by selectively weakening contraction while preserving stability.
Details
Motivation: Oversmoothing causes node representations to collapse as GCN depth increases. While many approaches address this through architectural modifications, the underlying spectral causes are often left implicit. The paper aims to provide a simple, interpretable solution that directly targets the spectral properties causing oversmoothing.Method: Laplacian-LoRA introduces a learnable, spectrally anchored correction to the fixed Laplacian propagation operator in standard GCNs. Instead of redesigning message passing, it adds a low-rank adaptation that selectively weakens contraction while preserving stability and the low-pass inductive bias. The method maintains interpretability through spectral analysis.
Result: Across multiple benchmark datasets and depths, Laplacian-LoRA consistently delays the onset of oversmoothing, extending the effective depth of GCNs by up to a factor of two. Embedding variance diagnostics confirm delayed representational collapse, and spectral analysis shows the correction is smooth, bounded, and well-behaved.
Conclusion: Oversmoothing is a depth-dependent spectral phenomenon that can be systematically delayed through modest, low-rank adaptation of the graph propagation operator. Laplacian-LoRA provides an interpretable solution that doesn’t require redesigning message passing architectures.
Abstract: Oversmoothing is a fundamental limitation of deep graph convolutional networks (GCNs), causing node representations to collapse as depth increases. While many prior approaches mitigate this effect through architectural modifications or residual mechanisms, the underlying spectral cause of oversmoothing is often left implicit. We propose Laplacian-LoRA, a simple and interpretable low-rank spectral adaptation of standard GCNs. Rather than redesigning message passing, Laplacian-LoRA introduces a learnable, spectrally anchored correction to the fixed Laplacian propagation operator, selectively weakening contraction while preserving stability and the low-pass inductive bias. Across multiple benchmark datasets and depths, Laplacian-LoRA consistently delays the onset of oversmoothing, extending the effective depth of GCNs by up to a factor of two. Embedding variance diagnostics confirm that these gains arise from delayed representational collapse, while learned spectral analysis demonstrates that the correction is smooth, bounded, and well behaved. Our results show that oversmoothing is a depth-dependent spectral phenomenon that can be systematically delayed through modest, low-rank adaptation of the graph propagation operator.
[736] VertCoHiRF: Decentralized Vertical Clustering Beyond k-means
Bruno Belucci, Karim Lounici, Vladimir R. Kostic, Katia Meziani
Main category: cs.LG
TL;DR: VertCoHiRF: A decentralized vertical federated clustering framework using structural consensus across heterogeneous feature views without sharing feature data.
Details
Motivation: Existing vertical federated learning approaches are limited to k-means variants, require centralized coordination, exchange feature-dependent statistics, and lack robustness to heterogeneous views or adversarial behavior.Method: Fully decentralized framework where agents cluster local feature spaces independently using any base method, then reconcile proposals through identifier-level consensus using decentralized ordinal ranking to select representative medoids, progressively building a shared hierarchical clustering.
Result: Competitive clustering performance in vertical federated settings with privacy by design (only exchanges sample IDs, cluster labels, and ordinal rankings), supports overlapping feature partitions and heterogeneous local methods, and produces interpretable shared Cluster Fusion Hierarchy.
Conclusion: VertCoHiRF enables robust, privacy-preserving vertical federated clustering without feature data exchange, supporting heterogeneous views and methods while providing interpretable multi-resolution consensus.
Abstract: Vertical Federated Learning (VFL) enables collaborative analysis across parties holding complementary feature views of the same samples, yet existing approaches are largely restricted to distributed variants of $k$-means, requiring centralized coordination or the exchange of feature-dependent numerical statistics, and exhibiting limited robustness under heterogeneous views or adversarial behavior. We introduce VertCoHiRF, a fully decentralized framework for vertical federated clustering based on structural consensus across heterogeneous views, allowing each agent to apply a base clustering method adapted to its local feature space in a peer-to-peer manner. Rather than exchanging feature-dependent statistics or relying on noise injection for privacy, agents cluster their local views independently and reconcile their proposals through identifier-level consensus. Consensus is achieved via decentralized ordinal ranking to select representative medoids, progressively inducing a shared hierarchical clustering across agents. Communication is limited to sample identifiers, cluster labels, and ordinal rankings, providing privacy by design while supporting overlapping feature partitions and heterogeneous local clustering methods, and yielding an interpretable shared Cluster Fusion Hierarchy (CFH) that captures cross-view agreement at multiple resolutions.We analyze communication complexity and robustness, and experiments demonstrate competitive clustering performance in vertical federated settings.
[737] Fair Decisions from Calibrated Scores: Achieving Optimal Classification While Satisfying Sufficiency
Etam Benger, Katrina Ligett
Main category: cs.LG
TL;DR: Exact solution for optimal binary classification under sufficiency fairness constraints using group-calibrated scores, with geometric characterization and post-processing algorithm.
Details
Motivation: While thresholding predicted probabilities is Bayes-optimal for binary classification, it violates statistical group fairness constraints. Under sufficiency (predictive parity), even perfectly group-calibrated scores violate fairness after thresholding, creating a need for optimal classification methods that satisfy sufficiency constraints.Method: Provides geometric characterization of feasible pairs of positive predictive value (PPV) and false omission rate (FOR) achievable by randomized classifiers under sufficiency. Derives a simple post-processing algorithm using only group-calibrated scores and group membership to attain optimal classifiers.
Result: Exact solution for optimal binary classification under sufficiency constraints, with algorithm that achieves optimal performance. Also identifies classifier minimizing deviation from separation (equalized odds) subject to sufficiency, showing comparable performance to optimum.
Conclusion: The paper provides a complete solution for fair binary classification under sufficiency constraints, with practical algorithms that achieve optimality using only group-calibrated scores and group information, addressing incompatibility between sufficiency and separation.
Abstract: Binary classification based on predicted probabilities (scores) is a fundamental task in supervised machine learning. While thresholding scores is Bayes-optimal in the unconstrained setting, using a single threshold generally violates statistical group fairness constraints. Under independence (statistical parity) and separation (equalized odds), such thresholding suffices when the scores already satisfy the corresponding criterion. However, this does not extend to sufficiency: even perfectly group-calibrated scores – including true class probabilities – violate predictive parity after thresholding. In this work, we present an exact solution for optimal binary (randomized) classification under sufficiency, assuming finite sets of group-calibrated scores. We provide a geometric characterization of the feasible pairs of positive predictive value (PPV) and false omission rate (FOR) achievable by such classifiers, and use it to derive a simple post-processing algorithm that attains the optimal classifier using only group-calibrated scores and group membership. Finally, since sufficiency and separation are generally incompatible, we identify the classifier that minimizes deviation from separation subject to sufficiency, and show that it can also be obtained by our algorithm, often achieving performance comparable to the optimum.
[738] Incorruptible Neural Networks: Training Models that can Generalize to Large Internal Perturbations
Philip Jacobson, Ben Feinberg, Suhas Kumar, Sapan Agarwal, T. Patrick Xiao, Christopher Bennett
Main category: cs.LG
TL;DR: The paper explores training neural networks robust to weight perturbations using SAM and RWP methods, analyzing both generalization and optimization aspects for noise-robust models.
Details
Motivation: The paper addresses two related problems: 1) Finding flat minima in neural network loss landscapes for better generalization, and 2) Training models robust to internal weight perturbations, which is important for future low-power hardware platforms where weight corruption may occur.Method: The paper investigates two methods: Sharpness-Aware Minimization (SAM) and Random-Weight Perturbation (RWP). It analyzes these from generalization (reducing noise-robust generalization gap) and optimization (maximizing performance under strong perturbations) perspectives. The study includes theoretical analysis and empirical experiments with dynamic adjustment of perturbation strength.
Result: The paper finds that over-regularized RWP training is optimal for noise-robust generalization. For small-magnitude noise, SAM’s adversarial objective outperforms RWP, but performs poorly for large-magnitude noise due to vanishing-gradient effects from uneven loss landscapes. Dynamic adjustment of perturbation strength improves optimization for these perturbed objectives.
Conclusion: The paper provides insights into training robust neural networks under weight perturbations, showing that different methods (SAM vs RWP) are optimal for different noise magnitudes, and that dynamic perturbation adjustment can improve optimization for noise-robust training.
Abstract: Flat regions of the neural network loss landscape have long been hypothesized to correlate with better generalization properties. A closely related but distinct problem is training models that are robust to internal perturbations to their weights, which may be an important need for future low-power hardware platforms. In this paper, we explore the usage of two methods, sharpness-aware minimization (SAM) and random-weight perturbation (RWP), to find minima robust to a variety of random corruptions to weights. We consider the problem from two angles: generalization (how do we reduce the noise-robust generalization gap) and optimization (how do we maximize performance from optimizers when subject to strong perturbations). First, we establish, both theoretically and empirically, that an over-regularized RWP training objective is optimal for noise-robust generalization. For small-magnitude noise, we find that SAM’s adversarial objective further improves performance over any RWP configuration, but performs poorly for large-magnitude noise. We link the cause of this to a vanishing-gradient effect, caused by unevenness in the loss landscape, affecting both SAM and RWP. Lastly, we demonstrate that dynamically adjusting the perturbation strength to match the evolution of the loss landscape improves optimizing for these perturbed objectives.
[739] Revisiting Robustness for LLM Safety Alignment via Selective Geometry Control
Yonghui Yang, Wenjian Tao, Jilong Liu, Xingyu Zhu, Junfeng Fang, Weibiao Huang, Le Wu, Richang Hong, Tat-Sent Chua
Main category: cs.LG
TL;DR: ShaPO is a geometry-aware preference optimization framework that improves LLM safety alignment robustness by selectively controlling alignment-critical parameter subspaces rather than applying uniform constraints.
Details
Motivation: Current safety alignment methods for large language models are brittle under domain shift and noisy preference supervision. Most robust alignment methods focus on data uncertainty but overlook optimization-induced fragility in preference-based objectives.Method: ShaPO enforces worst-case alignment objectives via selective geometry control over alignment-critical parameter subspaces, avoiding uniform geometry constraints that cause over-regularization. It has two instantiations: token-level ShaPO stabilizes likelihood-based surrogate optimization, while reward-level ShaPO enforces reward-consistent optimization under noisy supervision.
Result: Across diverse safety benchmarks and noisy preference settings, ShaPO consistently improves safety robustness over popular preference optimization methods. It also composes cleanly with data-robust objectives, yielding additional gains.
Conclusion: ShaPO demonstrates that robustness failures in LLM safety alignment cannot be addressed by data-centric methods alone, supporting the proposed optimization-geometry perspective for improving alignment robustness.
Abstract: Safety alignment of large language models remains brittle under domain shift and noisy preference supervision. Most existing robust alignment methods focus on uncertainty in alignment data, while overlooking optimization-induced fragility in preference-based objectives. In this work, we revisit robustness for LLM safety alignment from an optimization geometry perspective, and argue that robustness failures cannot be addressed by data-centric methods alone. We propose ShaPO, a geometry-aware preference optimization framework that enforces worst-case alignment objectives via selective geometry control over alignment-critical parameter subspace. By avoiding uniform geometry constraints, ShaPO mitigates the over-regularization that can harm robustness under distribution shift. We instantiate ShaPO at two levels: token-level ShaPO stabilizes likelihood-based surrogate optimization, while reward-level ShaPO enforces reward-consistent optimization under noisy supervision. Across diverse safety benchmarks and noisy preference settings, ShaPO consistently improves safety robustness over popular preference optimization methods. Moreover, ShaPO composes cleanly with data-robust objectives, yielding additional gains and empirically supporting the proposed optimization-geometry perspective.
[740] Scalable Dexterous Robot Learning with AR-based Remote Human-Robot Interactions
Yicheng Yang, Ruijiao Li, Lifeng Wang, Shuai Zheng, Shunzheng Ma, Keyu Zhang, Tuoyu Sun, Chenyun Dai, Jie Ding, Zhuo Zou
Main category: cs.LG
TL;DR: A unified framework for scalable robot manipulation learning using AR-based human-robot interaction for data collection, combining behavior cloning pretraining with contrastive learning-enhanced reinforcement learning for improved efficiency and robustness.
Details
Motivation: To address the challenge of scalable robot learning for dexterous manipulation tasks by establishing remote human-robot interactions via AR to efficiently collect expert demonstration data, overcoming limitations of traditional robot learning approaches.Method: Two-phase approach: 1) Pretraining via behavior cloning using AR-based human-robot interaction data; 2) Contrastive learning-enhanced reinforcement learning with a projection head for acceleration and event-driven augmented reward for safety enhancement.
Result: The method significantly speeds up inference and achieves much better success rates compared to classic PPO and SAC policies in both PyBullet simulations and real-world experiments, while overcoming policy collapse through contrastive learning.
Conclusion: The proposed unified framework effectively combines AR-based human demonstration collection with contrastive learning-enhanced RL to create efficient and robust manipulation policies for dexterous robot arm-hand systems.
Abstract: This paper focuses on the scalable robot learning for manipulation in the dexterous robot arm-hand systems, where the remote human-robot interactions via augmented reality (AR) are established to collect the expert demonstration data for improving efficiency. In such a system, we present a unified framework to address the general manipulation task problem. Specifically, the proposed method consists of two phases: i) In the first phase for pretraining, the policy is created in a behavior cloning (BC) manner, through leveraging the learning data from our AR-based remote human-robot interaction system; ii) In the second phase, a contrastive learning empowered reinforcement learning (RL) method is developed to obtain more efficient and robust policy than the BC, and thus a projection head is designed to accelerate the learning progress. An event-driven augmented reward is adopted for enhancing the safety. To validate the proposed method, both the physics simulations via PyBullet and real-world experiments are carried out. The results demonstrate that compared to the classic proximal policy optimization and soft actor-critic policies, our method not only significantly speeds up the inference, but also achieves much better performance in terms of the success rate for fulfilling the manipulation tasks. By conducting the ablation study, it is confirmed that the proposed RL with contrastive learning overcomes policy collapse. Supplementary demonstrations are available at https://cyberyyc.github.io/.
[741] Controllable Value Alignment in Large Language Models through Neuron-Level Editing
Yonghui Yang, Junwei Li, Jilong Liu, Yicheng He, Fengbin Zhu, Weibiao Huang, Le Wu, Richang Hong, Tat-Seng Chua
Main category: cs.LG
TL;DR: NeVA is a neuron-level editing framework for controllable value alignment in LLMs that reduces unintended activation of non-target values (value leakage) through sparse neuron identification and inference-time activation editing.
Details
Motivation: Existing steering-based alignment methods for LLMs suffer from limited controllability - steering target values often unintentionally activates non-target values (value leakage). There's a need for more precise, controllable value alignment without compromising general capabilities.Method: NeVA identifies sparse, value-relevant neurons in LLMs and performs inference-time activation editing. It uses a diagnostic notion of value leakage grounded in Schwartz’s value theory, with a normalized leakage metric. The framework enables fine-grained control without parameter updates or retraining.
Result: NeVA achieves stronger target value alignment with smaller performance degradation on general capabilities. It significantly reduces average value leakage, with residual effects largely confined to semantically related value classes.
Conclusion: NeVA offers a more controllable and interpretable mechanism for value alignment in LLMs, addressing the value leakage problem through neuron-level editing while maintaining model performance.
Abstract: Aligning large language models (LLMs) with human values has become increasingly important as their influence on human behavior and decision-making expands. However, existing steering-based alignment methods suffer from limited controllability: steering a target value often unintentionally activates other, non-target values. To characterize this limitation, we introduce value leakage, a diagnostic notion that captures the unintended activation of non-target values during value steering, along with a normalized leakage metric grounded in Schwartz’s value theory. In light of this analysis, we propose NeVA, a neuron-level editing framework for controllable value alignment in LLMs. NeVA identifies sparse, value-relevant neurons and performs inference-time activation editing, enabling fine-grained control without parameter updates or retraining. Experiments show that NeVA achieves stronger target value alignment while incurring smaller performance degradation on general capability. Moreover, NeVA significantly reduces the average leakage, with residual effects largely confined to semantically related value classes. Overall, NeVA offers a more controllable and interpretable mechanism for value alignment.
[742] UTOPIA: Unlearnable Tabular Data via Decoupled Shortcut Embedding
Jiaming He, Fuming Luo, Hongwei Li, Wenbo Jiang, Wenshu Fan, Zhenbo Shi, Xudong Jiang, Yi Yu
Main category: cs.LG
TL;DR: UTOPIA creates unlearnable tabular data by decoupling optimization into high-saliency features for semantic obfuscation and low-saliency redundant features for embedding hyper-correlated shortcuts, preventing unauthorized model training while preserving tabular validity.
Details
Motivation: Tabular data in finance and healthcare is highly sensitive but existing unlearnable example methods for vision data transfer poorly to tabular domains due to mixed numerical/categorical constraints and saliency sparsity where learning is dominated by few dimensions.Method: UTOPIA exploits feature redundancy to decouple optimization into two channels: (1) high saliency features for semantic obfuscation, and (2) low saliency redundant features for embedding hyper-correlated shortcuts. Under Spectral Dominance condition, it ensures poison spectrum overwhelms clean semantic spectrum for certified unlearnability.
Result: Extensive experiments across tabular datasets and models show UTOPIA drives unauthorized training toward near random performance, outperforming strong unlearnable example baselines and transferring well across different architectures.
Conclusion: UTOPIA provides effective protection for sensitive tabular data by creating constraint-aware dominant shortcuts while preserving tabular validity, addressing the unique challenges of tabular data protection compared to vision domains.
Abstract: Unlearnable examples (UE) have emerged as a practical mechanism to prevent unauthorized model training on private vision data, while extending this protection to tabular data is nontrivial. Tabular data in finance and healthcare is highly sensitive, yet existing UE methods transfer poorly because tabular features mix numerical and categorical constraints and exhibit saliency sparsity, with learning dominated by a few dimensions. Under a Spectral Dominance condition, we show certified unlearnability is feasible when the poison spectrum overwhelms the clean semantic spectrum. Guided by this, we propose Unlearnable Tabular Data via DecOuPled Shortcut EmbeddIng (UTOPIA), which exploits feature redundancy to decouple optimization into two channels: high saliency features for semantic obfuscation and low saliency redundant features for embedding a hyper correlated shortcut, yielding constraint-aware dominant shortcuts while preserving tabular validity. Extensive experiments across tabular datasets and models show UTOPIA drives unauthorized training toward near random performance, outperforming strong UE baselines and transferring well across architectures.
[743] FEM-Informed Hypergraph Neural Networks for Efficient Elastoplasticity
Jianchuan Yang, Xi Chen, Jidong Zhao
Main category: cs.LG
TL;DR: FHGNN embeds finite-element computations into hypergraph neural networks for physics-informed learning in computational mechanics, achieving improved accuracy and efficiency over PINNs for large elastoplastic problems.
Details
Motivation: To develop a physics-informed machine learning approach for computational mechanics that naturally aligns with sparse operators and unstructured discretizations, overcoming limitations of conventional PINNs in handling complex nonlinear solid mechanics problems.Method: Embed finite-element computations at nodes and Gauss points directly into message-passing layers of hypergraph neural networks, using a node element hypergraph whose edges encode mesh connectivity, with training driven purely by physics using a variational loss.
Result: Substantially improved accuracy and efficiency over recent PINN variants on 3D benchmarks including cyclic loading with isotropic/kinematic hardening, scales effectively to large elastoplastic problems with GPU-parallel tensor operations.
Conclusion: Establishes a foundation for scalable, physics-embedded learning in nonlinear solid mechanics by combining graph neural networks with finite-element methods in a numerically consistent framework.
Abstract: Graph neural networks (GNNs) naturally align with sparse operators and unstructured discretizations, making them a promising paradigm for physics-informed machine learning in computational mechanics. Motivated by discrete physics losses and Hierarchical Deep Learning Neural Network (HiDeNN) constructions, we embed finite-element (FEM) computations at nodes and Gauss points directly into message-passing layers and propose a numerically consistent FEM-Informed Hypergraph Neural Networks (FHGNN). Similar to conventional physics-informed neural networks (PINNs), training is purely physics-driven and requires no labeled data: the input is a node element hypergraph whose edges encode mesh connectivity. Guided by empirical results and condition-number analysis, we adopt an efficient variational loss. Validated on 3D benchmarks, including cyclic loading with isotropic/kinematic hardening, the proposed method delivers substantially improved accuracy and efficiency over recent, competitive PINN variants. By leveraging GPU-parallel tensor operations and the discrete representation, it scales effectively to large elastoplastic problems and can be competitive with, or faster than, multi-core FEM implementations at comparable accuracy. This work establishes a foundation for scalable, physics-embedded learning in nonlinear solid mechanics.
[744] Privately Learning Decision Lists and a Differentially Private Winnow
Mark Bun, William Fang
Main category: cs.LG
TL;DR: New differentially private algorithms for learning decision lists and large-margin halfspaces in PAC and online models with minimal privacy overhead compared to non-private baselines.
Details
Motivation: To develop differentially private machine learning algorithms that maintain strong theoretical guarantees while preserving privacy, specifically for fundamental learning problems like decision lists and halfspaces.Method: Develops new differentially private algorithms for PAC and online learning settings. In PAC model: computationally efficient algorithm for decision lists. In online model: private analog of Winnow algorithm for halfspaces with polylogarithmic mistake bounds.
Result: Achieves minimal sample overhead over best non-private algorithms for decision lists in PAC model, and obtains mistake bounds polylogarithmic in dimension and inverse polynomial in margin for halfspaces in online model.
Conclusion: The paper presents differentially private algorithms that qualitatively match state-of-the-art non-private guarantees for fundamental learning problems, demonstrating that privacy can be achieved with minimal performance degradation.
Abstract: We give new differentially private algorithms for the classic problems of learning decision lists and large-margin halfspaces in the PAC and online models. In the PAC model, we give a computationally efficient algorithm for learning decision lists with minimal sample overhead over the best non-private algorithms. In the online model, we give a private analog of the influential Winnow algorithm for learning halfspaces with mistake bound polylogarithmic in the dimension and inverse polynomial in the margin. As an application, we describe how to privately learn decision lists in the online model, qualitatively matching state-of-the art non-private guarantees.
[745] Dichotomy of Feature Learning and Unlearning: Fast-Slow Analysis on Neural Networks with Stochastic Gradient Descent
Shota Imai, Sota Nishiyama, Masaaki Imaizumi
Main category: cs.LG
TL;DR: Theoretical analysis of feature unlearning in two-layer neural networks using infinite-width limit and fast-slow dynamics, revealing conditions for feature unlearning and mitigation strategies.
Details
Motivation: Understanding the nontrivial structures in gradient-based training dynamics of neural networks, particularly the phenomenon of feature unlearning where networks progressively lose previously learned features during extended training.Method: Analyze infinite-width limit of two-layer neural networks with large-batch stochastic gradient descent. Derive differential equations with different time scales using Tensor Programs and singular perturbation theory. Study fast-slow dynamics where first-layer weights align rapidly while second-layer weights develop slowly.
Result: Revealed mechanism and conditions for feature unlearning: (1) strength of primary nonlinear term in data induces feature unlearning, (2) initial scale of second-layer weights mitigates feature unlearning. Numerical validation and scaling laws provided.
Conclusion: Feature unlearning in neural networks is governed by fast-slow dynamics and critical manifold flow direction. Understanding these mechanisms provides insights into training dynamics and potential mitigation strategies for feature preservation.
Abstract: The dynamics of gradient-based training in neural networks often exhibit nontrivial structures; hence, understanding them remains a central challenge in theoretical machine learning. In particular, a concept of feature unlearning, in which a neural network progressively loses previously learned features over long training, has gained attention. In this study, we consider the infinite-width limit of a two-layer neural network updated with a large-batch stochastic gradient, then derive differential equations with different time scales, revealing the mechanism and conditions for feature unlearning to occur. Specifically, we utilize the fast-slow dynamics: while an alignment of first-layer weights develops rapidly, the second-layer weights develop slowly. The direction of a flow on a critical manifold, determined by the slow dynamics, decides whether feature unlearning occurs. We give numerical validation of the result, and derive theoretical grounding and scaling laws of the feature unlearning. Our results yield the following insights: (i) the strength of the primary nonlinear term in data induces the feature unlearning, and (ii) an initial scale of the second-layer weights mitigates the feature unlearning. Technically, our analysis utilizes Tensor Programs and the singular perturbation theory.
[746] Scout Before You Attend: Sketch-and-Walk Sparse Attention for Efficient LLM Inference
Hoang Anh Duy Le, Sahil Joshi, Zeyu Yang, Zhaozhuo Xu, Anshumali Shrivastava
Main category: cs.LG
TL;DR: Sketch&Walk Attention: A training-free sparse attention method using lightweight sketching and deterministic walk to reduce computational cost while maintaining accuracy.
Details
Motivation: Self-attention dominates computational and memory costs in long-context LLM inference for both prefill and decode phases, creating a need for efficient sparse attention methods.Method: Uses Hadamard sketching for inexpensive approximations of attention scores, aggregates estimates across layers via walk mechanism to capture attention influence beyond direct token interactions, selects top-k attention blocks for dynamic sparsity.
Result: Maintains near-lossless accuracy at 20% attention density, slightly outperforms dense attention in some settings, achieves up to 6x inference speedup across various models and tasks.
Conclusion: Sketch&Walk Attention provides an effective training-free solution for reducing attention computation costs while preserving model performance, applicable to both prefill and decode phases.
Abstract: Self-attention dominates the computational and memory cost of long-context LLM inference across both prefill and decode phases. To address this challenge, we introduce Sketch&Walk Attention, a training-free sparse attention method that determines sparsity with lightweight sketches and deterministic walk. Sketch&Walk applies Hadamard sketching to get inexpensive approximations of attention scores, then aggregates these estimates across layers via a walk mechanism that captures attention influence beyond direct interactions between tokens. The accumulated walk scores are used to select top-k attention blocks, enabling dynamic sparsity with a single training-free algorithm that applies uniformly to both the prefill and decode phases, together with custom sparse attention kernels. Across a wide range of models and tasks, Sketch&Walk maintains near-lossless accuracy at 20% attention density and can slightly outperform dense attention in some settings, while achieving up to 6x inference speedup.
[747] BitLogic: Training Framework for Gradient-Based FPGA-Native Neural Networks
Simon Bührer, Andreas Plesner, Aczel Till, Roger Wattenhofer
Main category: cs.LG
TL;DR: BitLogic is a gradient-based framework for FPGA-native neural networks that replaces MAC operations with differentiable LUT nodes, enabling efficient hardware realization with automated RTL export.
Details
Motivation: Deep neural network inference costs are increasingly driven by deployment rather than training, motivating hardware-specialized alternatives. FPGAs provide an attractive substrate for such specialization, but existing FPGA-based neural approaches are fragmented and difficult to compare.Method: BitLogic replaces multiply-accumulate operations with differentiable Lookup Table (LUT) nodes that map directly to FPGA primitives. It offers a modular functional API, learned encoders, hardware-aware heads, and boundary-consistent LUT relaxations. An automated RTL export pipeline translates trained PyTorch models into synthesizable HDL.
Result: Experiments show competitive accuracy and substantial FPGA efficiency gains, including 72.3% test accuracy on CIFAR-10 with fewer than 0.3M logic gates, and sub-20 ns single-sample inference using only LUT resources.
Conclusion: BitLogic provides an effective framework for FPGA-native neural networks that bridges the gap between software training and hardware deployment, achieving efficient inference through LUT-based computation.
Abstract: The energy and latency costs of deep neural network inference are increasingly driven by deployment rather than training, motivating hardware-specialized alternatives to arithmetic-heavy models. Field-Programmable Gate Arrays (FPGAs) provide an attractive substrate for such specialization, yet existing FPGA-based neural approaches are fragmented and difficult to compare. We present BitLogic, a fully gradient-based, end-to-end trainable framework for FPGA-native neural networks built around Lookup Table (LUT) computation. BitLogic replaces multiply-accumulate operations with differentiable LUT nodes that map directly to FPGA primitives, enabling native binary computation, sparse connectivity, and efficient hardware realization. The framework offers a modular functional API supporting diverse architectures, along with learned encoders, hardware-aware heads, and multiple boundary-consistent LUT relaxations. An automated Register Transfer Level (RTL) export pipeline translates trained PyTorch models into synthesizable HDL, ensuring equivalence between software and hardware inference. Experiments across standard vision benchmarks and heterogeneous hardware platforms demonstrate competitive accuracy and substantial gains in FPGA efficiency, including 72.3% test accuracy on CIFAR-10 achieved with fewer than 0.3M logic gates, while attaining sub-20 ns single-sample inference using only LUT resources.
[748] Nonparametric Bayesian Optimization for General Rewards
Zishi Zhang, Tao Ren, Yijie Peng
Main category: cs.LG
TL;DR: Proposes a Bayesian optimization algorithm with no-regret guarantee using infinite Gaussian process surrogate model for general reward settings with measurement noise.
Details
Motivation: Bayesian optimization typically assumes Gaussian process models, which may not capture complex reward distributions. There's a need for BO algorithms that work with broader reward models while maintaining theoretical guarantees and computational efficiency.Method: Introduces infinite Gaussian process (∞-GP), a Bayesian nonparametric model that places priors on reward distributions. Combines ∞-GP with Thompson Sampling for exploration-exploitation balance. Uses truncated Gibbs sampling for computational scalability.
Result: Achieves no-regret guarantee for general reward settings requiring only Lipschitz continuity. Empirical results show state-of-the-art performance, especially for non-stationary, heavy-tailed, or ill-conditioned rewards.
Conclusion: The ∞-GP framework extends Bayesian optimization to handle broader reward models while maintaining theoretical guarantees and computational efficiency, outperforming classical GP-based methods in complex reward settings.
Abstract: This work focuses on Bayesian optimization (BO) under reward model uncertainty. We propose the first BO algorithm that achieves no-regret guarantee in a general reward setting, requiring only Lipschitz continuity of the objective function and accommodating a broad class of measurement noise. The core of our approach is a novel surrogate model, termed as infinite Gaussian process ($\infty$-GP). It is a Bayesian nonparametric model that places a prior on the space of reward distributions, enabling it to represent a substantially broader class of reward models than classical Gaussian process (GP). The $\infty$-GP is used in combination with Thompson Sampling (TS) to enable effective exploration and exploitation. Correspondingly, we develop a new TS regret analysis framework for general rewards, which relates the regret to the total variation distance between the surrogate model and the true reward distribution. Furthermore, with a truncated Gibbs sampling procedure, our method is computationally scalable, incurring minimal additional memory and computational complexities compared to classical GP. Empirical results demonstrate state-of-the-art performance, particularly in settings with non-stationary, heavy-tailed, or other ill-conditioned rewards.
[749] Learning Molecular Chirality via Chiral Determinant Kernels
Runhan Shi, Zhicheng Zhang, Letian Chen, Gufeng Yu, Yang Yang
Main category: cs.LG
TL;DR: ChiDeK introduces a novel framework for molecular representation learning that systematically encodes stereochemical information, particularly chirality, using chiral determinant kernels and cross-attention mechanisms to handle both central and axial chirality.
Details
Motivation: Current machine learning models struggle to capture molecular chirality due to geometric complexity and limitations of traditional representations that lack explicit stereochemical encoding. Existing approaches focus mainly on central chirality and fail to generalize to more complex forms like axial chirality.Method: Proposes ChiDeK framework with chiral determinant kernels to encode SE(3)-invariant chirality matrix, using cross-attention to integrate stereochemical information from local chiral centers into global molecular representation. Creates new benchmark for axial chirality evaluation.
Result: Achieves substantial improvements over state-of-the-art baselines across four tasks: R/S configuration classification, enantiomer ranking, ECD spectrum prediction, and OR prediction. Most notably yields over 7% higher accuracy on axially chiral tasks on average.
Conclusion: ChiDeK provides a unified architecture for explicit modeling of chiral-related features, capable of jointly encoding central and axial chirality, addressing a fundamental challenge in molecular representation learning.
Abstract: Chirality is a fundamental molecular property that governs stereospecific behavior in chemistry and biology. Capturing chirality in machine learning models remains challenging due to the geometric complexity of stereochemical relationships and the limitations of traditional molecular representations that often lack explicit stereochemical encoding. Existing approaches to chiral molecular representation primarily focus on central chirality, relying on handcrafted stereochemical tags or limited 3D encodings, and thus fail to generalize to more complex forms such as axial chirality. In this work, we introduce ChiDeK (Chiral Determinant Kernels), a framework that systematically integrates stereogenic information into molecular representation learning. We propose the chiral determinant kernel to encode the SE(3)-invariant chirality matrix and employ cross-attention to integrate stereochemical information from local chiral centers into the global molecular representation. This design enables explicit modeling of chiral-related features within a unified architecture, capable of jointly encoding central and axial chirality. To support the evaluation of axial chirality, we construct a new benchmark for electronic circular dichroism (ECD) and optical rotation (OR) prediction. Across four tasks, including R/S configuration classification, enantiomer ranking, ECD spectrum prediction, and OR prediction, ChiDeK achieves substantial improvements over state-of-the-art baselines, most notably yielding over 7% higher accuracy on axially chiral tasks on average.
[750] Achieving Optimal Static and Dynamic Regret Simultaneously in Bandits with Deterministic Losses
Jian Qian, Chen-Yu Wei
Main category: cs.LG
TL;DR: Simultaneous optimal static and dynamic regret is impossible against adaptive adversaries but achievable against oblivious adversaries with deterministic losses, using a novel algorithm based on negative static regret compensation and Blackwell approachability.
Details
Motivation: The paper addresses the fundamental problem of simultaneously achieving optimal static regret (comparing to best fixed arm) and dynamic regret (comparing to best sequence of arms) in adversarial multi-armed bandits. Previous work showed this is impossible against adaptive adversaries, but the possibility against oblivious adversaries remained open.Method: The authors first extend the impossibility result to deterministic losses, then present a novel algorithm that achieves optimal static and dynamic regret simultaneously against oblivious adversaries. The algorithm uses negative static regret to compensate for exploration overhead when controlling dynamic regret, and leverages Blackwell approachability to jointly control both regret measures.
Result: The paper demonstrates a fundamental separation between adaptive and oblivious adversaries when multiple regret benchmarks are considered simultaneously. It provides the first algorithm achieving optimal static and dynamic regret simultaneously against oblivious adversaries with deterministic losses.
Conclusion: The work reveals that simultaneous optimality of static and dynamic regret is possible against oblivious adversaries but impossible against adaptive adversaries, providing new insights into the long-standing problem of simultaneously achieving optimal regret against switching benchmarks with different numbers of switches.
Abstract: In adversarial multi-armed bandits, two performance measures are commonly used: static regret, which compares the learner to the best fixed arm, and dynamic regret, which compares it to the best sequence of arms. While optimal algorithms are known for each measure individually, there is no known algorithm achieving optimal bounds for both simultaneously. Marinov and Zimmert [2021] first showed that such simultaneous optimality is impossible against an adaptive adversary. Our work takes a first step to demonstrate its possibility against an oblivious adversary when losses are deterministic. First, we extend the impossibility result of Marinov and Zimmert [2021] to the case of deterministic losses. Then, we present an algorithm achieving optimal static and dynamic regret simultaneously against an oblivious adversary. Together, they reveal a fundamental separation between adaptive and oblivious adversaries when multiple regret benchmarks are considered simultaneously. It also provides new insight into the long open problem of simultaneously achieving optimal regret against switching benchmarks of different numbers of switches. Our algorithm uses negative static regret to compensate for the exploration overhead incurred when controlling dynamic regret, and leverages Blackwell approachability to jointly control both regrets. This yields a new model selection procedure for bandits that may be of independent interest.
[751] Sign-Based Optimizers Are Effective Under Heavy-Tailed Noise
Dingzhi Yu, Hongyi Tao, Yuanyu Wan, Luo Luo, Lijun Zhang
Main category: cs.LG
TL;DR: Sign-based optimizers (Lion, Muon) outperform AdamW for LLM training; theoretical analysis shows they’re better suited for heavy-tailed gradient noise common in language modeling.
Details
Motivation: Sign-based optimization algorithms like Lion and Muon have shown superior empirical performance over AdamW in training large language models, but there's no theoretical understanding of why they outperform variance-adapted methods.Method: Introduce a novel generalized heavy-tailed noise condition that captures LLM gradient behavior better than standard assumptions. Analyze SignSGD, Lion, Muon, and Muonlight under this noise model, establishing sharp convergence rates for generalized smooth function classes.
Result: Theoretical analysis shows sign-based optimizers achieve convergence rates matching or surpassing previous best-known bounds under heavy-tailed noise. LLM pretraining experiments validate the theoretical insights and confirm the proposed noise models align with practice.
Conclusion: Sign-based optimizers are naturally suited to handle the heavy-tailed gradient noise observed in language modeling, providing theoretical justification for their empirical superiority over variance-adapted methods like AdamW.
Abstract: While adaptive gradient methods are the workhorse of modern machine learning, sign-based optimization algorithms such as Lion and Muon have recently demonstrated superior empirical performance over AdamW in training large language models (LLM). However, a theoretical understanding of why sign-based updates outperform variance-adapted methods remains elusive. In this paper, we aim to bridge the gap between theory and practice through the lens of heavy-tailed gradient noise, a phenomenon frequently observed in language modeling tasks. Theoretically, we introduce a novel generalized heavy-tailed noise condition that captures the behavior of LLMs more accurately than standard finite variance assumptions. Under this noise model, we establish sharp convergence rates of SignSGD and Lion for generalized smooth function classes, matching or surpassing previous best-known bounds. Furthermore, we extend our analysis to Muon and Muonlight, providing what is, to our knowledge, the first rigorous analysis of matrix optimization under heavy-tailed stochasticity. These results offer a strong theoretical justification for the empirical superiority of sign-based optimizers, showcasing that they are naturally suited to handle the noisy gradients associated with heavy tails. Empirically, LLM pretraining experiments validate our theoretical insights and confirm that our proposed noise models are well-aligned with practice.
[752] Brep2Shape: Boundary and Shape Representation Alignment via Self-Supervised Transformers
Yuanxu Sun, Yuezhou Ma, Haixu Wu, Guanyang Zeng, Muye Chen, Jianmin Wang, Mingsheng Long
Main category: cs.LG
TL;DR: Brep2Shape is a self-supervised pre-training method that bridges the representation gap in CAD boundary representations by aligning abstract B-rep models with intuitive shape representations using geometry-aware tasks and a dual transformer architecture.
Details
Motivation: Existing deep learning methods for CAD boundary representations suffer from a representation gap: continuous approaches offer analytical precision but are visually abstract, while discrete methods provide intuitive clarity at the expense of geometric precision. There's a need to bridge this gap for better CAD model processing.Method: Proposes Brep2Shape with: 1) Geometry-aware task predicting dense spatial points from parametric Bézier control points, 2) Dual Transformer backbone with parallel streams encoding surface and curve tokens separately, 3) Topology attention to model interdependencies between surfaces and curves for topological consistency.
Result: Achieves state-of-the-art accuracy and faster convergence across various downstream tasks, demonstrating significant scalability and effectiveness in bridging the representation gap for CAD models.
Conclusion: Brep2Shape successfully bridges the representation gap in CAD boundary representations through self-supervised pre-training, enabling better understanding of physical manifolds from abstract coefficients while maintaining topological consistency.
Abstract: Boundary representation (B-rep) is the industry standard for computer-aided design (CAD). While deep learning shows promise in processing B-rep models, existing methods suffer from a representation gap: continuous approaches offer analytical precision but are visually abstract, whereas discrete methods provide intuitive clarity at the expense of geometric precision. To bridge this gap, we introduce Brep2Shape, a novel self-supervised pre-training method designed to align abstract boundary representations with intuitive shape representations. Our method employs a geometry-aware task where the model learns to predict dense spatial points from parametric Bézier control points, enabling the network to better understand physical manifolds derived from abstract coefficients. To enhance this alignment, we propose a Dual Transformer backbone with parallel streams that independently encode surface and curve tokens to capture their distinct geometric properties. Moreover, the topology attention is integrated to model the interdependencies between surfaces and curves, thereby maintaining topological consistency. Experimental results demonstrate that Brep2Shape offers significant scalability, achieving state-of-the-art accuracy and faster convergence across various downstream tasks.
[753] Active Learning Using Aggregated Acquisition Functions: Accuracy and Sustainability Analysis
Cédric Jung, Shirin Salehi, Anke Schmeink
Main category: cs.LG
TL;DR: The paper proposes aggregated acquisition functions for active learning to address the exploration-exploitation dilemma, reducing annotation costs and energy consumption while maintaining accuracy.
Details
Motivation: Active learning aims to reduce annotation costs and energy consumption in neural network training by strategically selecting informative samples. The paper addresses the exploration-exploitation dilemma in acquisition functions and aims to develop more sustainable, energy-aware AI.Method: The authors implement and evaluate various state-of-the-art acquisition functions, then introduce six aggregation structures: series, parallel, hybrid, adaptive feedback, random exploration, and annealing exploration. These aggregated functions address batch mode inefficiency and cold start problems.
Result: The aggregated acquisition functions reduce computational costs while maintaining or improving accuracy. Innovative approaches like alternating between BALD and BADGE show robust results, with sequential approaches achieving same performance with 12% fewer samples and reducing acquisition cost by almost half.
Conclusion: The proposed aggregation structures effectively address active learning pathologies and contribute to more sustainable AI by balancing accuracy and energy consumption, demonstrating potential for reducing computational costs in machine learning.
Abstract: Active learning (AL) is a machine learning (ML) approach that strategically selects the most informative samples for annotation during training, aiming to minimize annotation costs. This strategy not only reduces labeling expenses but also results in energy savings during neural network training, thereby enhancing both data and energy efficiency. In this paper, we implement and evaluate various state-of-the-art acquisition functions, analyzing their accuracy and computational costs, while discussing the advantages and disadvantages of each method. Our findings reveal that representativity-based acquisition functions effectively explore the dataset but do not prioritize boundary decisions, whereas uncertainty-based acquisition functions focus on refining boundary decisions already identified by the neural network. This trade-off is known as the exploration-exploitation dilemma. To address this dilemma, we introduce six aggregation structures: series, parallel, hybrid, adaptive feedback, random exploration, and annealing exploration. Our aggregated acquisition functions alleviate common AL pathologies such as batch mode inefficiency and the cold start problem. Additionally, we focus on balancing accuracy and energy consumption, contributing to the development of more sustainable, energy-aware artificial intelligence (AI). We evaluate our proposed structures on various models and datasets. Our results demonstrate the potential of these structures to reduce computational costs while maintaining or even improving accuracy. Innovative aggregation approaches, such as alternating between acquisition functions such as BALD and BADGE, have shown robust results. Sequentially running functions like $K$-Centers followed by BALD has achieved the same performance goals with up to 12% fewer samples, while reducing the acquisition cost by almost half.
[754] Proximal Action Replacement for Behavior Cloning Actor-Critic in Offline Reinforcement Learning
Jinzong Dong, Wei Huang, Jianshu Zhang, Zhuo Chen, Xinzhe Yuan, Qinying Gu, Zhaohui Jiang, Nanyang Ye
Main category: cs.LG
TL;DR: PAR (Proximal Action Replacement) improves offline RL by replacing low-value actions with high-value actions from a stable actor, overcoming limitations of behavior cloning regularization that can impose performance ceilings.
Details
Motivation: Behavior cloning regularization in offline RL can impose a performance ceiling when dataset actions are suboptimal, preventing actors from exploiting high-value regions suggested by critics, especially in later training when imitation dominates.Method: Proximal Action Replacement (PAR) - a plug-and-play training sample replacer that progressively replaces low-value actions with high-value actions generated by a stable actor, broadening action exploration while reducing impact of low-value data.
Result: Extensive experiments across offline RL benchmarks show PAR consistently improves performance and approaches state-of-the-art when combined with basic TD3+BC.
Conclusion: PAR effectively breaks the performance ceiling imposed by behavior cloning regularization in offline RL by enabling better exploitation of high-value regions while maintaining stability.
Abstract: Offline reinforcement learning (RL) optimizes policies from a previously collected static dataset and is an important branch of RL. A popular and promising approach is to regularize actor-critic methods with behavior cloning (BC), which yields realistic policies and mitigates bias from out-of-distribution actions, but can impose an often-overlooked performance ceiling: when dataset actions are suboptimal, indiscriminate imitation structurally prevents the actor from fully exploiting high-value regions suggested by the critic, especially in later training when imitation is already dominant. We formally analyzed this limitation by investigating convergence properties of BC-regularized actor-critic optimization and verified it on a controlled continuous bandit task. To break this ceiling, we propose proximal action replacement (PAR), a plug-and-play training sample replacer that progressively replaces low-value actions with high-value actions generated by a stable actor, broadening the action exploration space while reducing the impact of low-value data. PAR is compatible with multiple BC regularization paradigms. Extensive experiments across offline RL benchmarks show that PAR consistently improves performance and approaches state-of-the-art when combined with the basic TD3+BC.
[755] Data-Aware and Scalable Sensitivity Analysis for Decision Tree Ensembles
Namrita Varshney, Ashutosh Gupta, Arhaan Ahmad, Tanay V. Tayal, S. Akshay
Main category: cs.LG
TL;DR: A data-aware sensitivity analysis framework for decision tree ensembles that generates realistic examples close to training distribution to identify model weaknesses, with MILP/SMT optimization techniques for scalability.
Details
Motivation: Decision tree ensembles are widely used in critical domains, requiring robustness and sensitivity analysis for trustworthiness. Existing sensitivity analysis approaches often produce unrealistic examples far from training distribution, limiting interpretability and practical value.Method: Proposes a data-aware sensitivity framework constraining examples to remain close to dataset. Develops novel techniques using mixed-integer linear programming (MILP) and satisfiability modulo theories (SMT) encodings with optimizations for scalability.
Result: Strengthens NP-hardness proof for sensitivity verification, develops MILP optimizations enabling verification of multiclass ensembles, introduces data-aware framework, and demonstrates scalability to ensembles with up to 800 trees of depth 8 with substantial improvements over state-of-the-art.
Conclusion: Provides a practical foundation for analyzing reliability and fairness of tree-based models in high-stakes applications through realistic sensitivity analysis that stays close to training distribution.
Abstract: Decision tree ensembles are widely used in critical domains, making robustness and sensitivity analysis essential to their trustworthiness. We study the feature sensitivity problem, which asks whether an ensemble is sensitive to a specified subset of features – such as protected attributes – whose manipulation can alter model predictions. Existing approaches often yield examples of sensitivity that lie far from the training distribution, limiting their interpretability and practical value. We propose a data-aware sensitivity framework that constrains the sensitive examples to remain close to the dataset, thereby producing realistic and interpretable evidence of model weaknesses. To this end, we develop novel techniques for data-aware search using a combination of mixed-integer linear programming (MILP) and satisfiability modulo theories (SMT) encodings. Our contributions are fourfold. First, we strengthen the NP-hardness result for sensitivity verification, showing it holds even for trees of depth 1. Second, we develop MILP-optimizations that significantly speed up sensitivity verification for single ensembles and for the first time can also handle multiclass tree ensembles. Third, we introduce a data-aware framework generating realistic examples close to the training distribution. Finally, we conduct an extensive experimental evaluation on large tree ensembles, demonstrating scalability to ensembles with up to 800 trees of depth 8, achieving substantial improvements over the state of the art. This framework provides a practical foundation for analyzing the reliability and fairness of tree-based models in high-stakes applications.
[756] On the Importance of a Multi-Scale Calibration for Quantization
Seungwoo Son, Ingyu Seong, Junhan Kim, Hyemi Jang, Yongkweon Jeon
Main category: cs.LG
TL;DR: MaCa introduces length-aware Hessian construction for LLM quantization by incorporating multi-scale sequence length information to improve accuracy under low-bit quantization.
Details
Motivation: Current PTQ methods use random fixed-length calibration sequences, ignoring that LLM inputs are variable-length. This causes Hessian estimates from fixed-length calibration to misrepresent weight importance across different input scenarios, leading to suboptimal quantization.Method: MaCa (Matryoshka Calibration) incorporates multi-scale sequence length information into Hessian estimation and regularizes each sequence as an independent sample, creating more stable and accurate Hessian matrices for quantization.
Result: Experiments on state-of-the-art LLMs (Qwen3, Gemma3, LLaMA3) show MaCa consistently improves accuracy under low-bit quantization and is compatible with existing PTQ frameworks.
Conclusion: MaCa addresses the variable-length nature of LLM inputs in quantization, offering a lightweight enhancement that improves quantization accuracy by better capturing weight importance across different input scenarios.
Abstract: Post-training quantization (PTQ) is a cornerstone for efficiently deploying large language models (LLMs), where a small calibration set critically affects quantization performance. However, conventional practices rely on random sequences of fixed length, overlooking the variable-length nature of LLM inputs. Input length directly influences the activation distribution and, consequently, the weight importance captured by the Hessian, which in turn affects quantization outcomes. As a result, Hessian estimates derived from fixed-length calibration may fail to represent the true importance of weights across diverse input scenarios. We propose MaCa (Matryoshka Calibration), a simple yet effective method for length-aware Hessian construction. MaCa (i) incorporates multi-scale sequence length information into Hessian estimation and (ii) regularizes each sequence as an independent sample, yielding a more stable and fruitful Hessian for accurate quantization. Experiments on state-of-the-art LLMs (e.g., Qwen3, Gemma3, LLaMA3) demonstrate that MaCa consistently improves accuracy under low bit quantization, offering a lightweight enhancement compatible with existing PTQ frameworks. To the best of our knowledge, this is the first work to systematically highlight the role of multi-scale calibration in LLM quantization.
[757] Bandit Allocational Instability
Yilun Chen, Jiaqi Lu
Main category: cs.LG
TL;DR: The paper establishes a fundamental trade-off between regret and allocation variability in multi-armed bandit algorithms, showing that R_T·S_T=Ω(T^{3/2}) and introduces UCB-f algorithm to achieve Pareto optimality.
Details
Motivation: Modern applications of bandit algorithms in platform operations and post-bandit statistical inference suffer from high variation in arm allocations, which can be harmful. The paper aims to quantify and address this allocation variability problem.Method: Introduces allocation variability as a new performance metric (largest standard deviation of arm pulls). Establishes theoretical lower bound R_T·S_T=Ω(T^{3/2}) for any bandit algorithm. Proposes UCB-f, a generalization of UCB1 with tunable parameters to achieve Pareto optimal trade-offs.
Result: Proves fundamental trade-off: any algorithm with sublinear regret must have allocation variability ω(√T). Shows UCB-f can achieve any point on the Pareto frontier R_T·S_T=Θ̃(T^{3/2}). Resolves an open question from Praharaj and Khamaru (2025).
Conclusion: There’s an inherent trade-off between regret minimization and allocation stability in bandit algorithms. The UCB-f algorithm provides a tunable solution to navigate this trade-off, with implications for practical applications in platform operations and statistical inference.
Abstract: When multi-armed bandit (MAB) algorithms allocate pulls among competing arms, the resulting allocation can exhibit huge variation. This is particularly harmful in modern applications such as learning-enhanced platform operations and post-bandit statistical inference. Thus motivated, we introduce a new performance metric of MAB algorithms termed allocation variability, which is the largest (over arms) standard deviation of an arm’s number of pulls. We establish a fundamental trade-off between allocation variability and regret, the canonical performance metric of reward maximization. In particular, for any algorithm, the worst-case regret $R_T$ and worst-case allocation variability $S_T$ must satisfy $R_T \cdot S_T=Ω(T^{\frac{3}{2}})$ as $T\rightarrow\infty$, as long as $R_T=o(T)$. This indicates that any minimax regret-optimal algorithm must incur worst-case allocation variability $Θ(T)$, the largest possible scale; while any algorithm with sublinear worst-case regret must necessarily incur ${S}_T= ω(\sqrt{T})$. We further show that this lower bound is essentially tight, and that any point on the Pareto frontier $R_T \cdot S_T=\tildeΘ(T^{3/2})$ can be achieved by a simple tunable algorithm UCB-f, a generalization of the classic UCB1. Finally, we discuss implications for platform operations and for statistical inference, when bandit algorithms are used. As a byproduct of our result, we resolve an open question of Praharaj and Khamaru (2025).
[758] Bipartite Graph Attention-based Clustering for Large-scale scRNA-seq Data
Zhuomin Liang, Liang Bai, Xian Yang
Main category: cs.LG
TL;DR: BGFormer: A bipartite graph transformer model for scRNA-seq clustering with linear computational complexity using learnable anchor tokens
Details
Motivation: Existing transformer-based scRNA-seq clustering methods have O(n²) computational complexity, limiting scalability to large datasets. Need for more efficient transformer architecture for single-cell analysis.Method: Proposes BGFormer with learnable anchor tokens as shared reference points. Uses bipartite graph attention mechanism to learn similarity between cells and anchor tokens, reducing complexity to linear with respect to cell count.
Result: BGFormer achieves linear computational complexity, making it scalable to large scRNA-seq datasets. Experimental results demonstrate effectiveness and scalability on multiple large-scale datasets.
Conclusion: BGFormer provides an efficient transformer-based solution for scRNA-seq clustering that overcomes computational limitations of previous methods while maintaining clustering performance.
Abstract: scRNA-seq clustering is a critical task for analyzing single-cell RNA sequencing (scRNA-seq) data, as it groups cells with similar gene expression profiles. Transformers, as powerful foundational models, have been applied to scRNA-seq clustering. Their self-attention mechanism automatically assigns higher attention weights to cells within the same cluster, enhancing the distinction between clusters. Existing methods for scRNA-seq clustering, such as graph transformer-based models, treat each cell as a token in a sequence. Their computational and space complexities are $\mathcal{O}(n^2)$ with respect to the number of cells, limiting their applicability to large-scale scRNA-seq datasets.To address this challenge, we propose a Bipartite Graph Transformer-based clustering model (BGFormer) for scRNA-seq data. We introduce a set of learnable anchor tokens as shared reference points to represent the entire dataset. A bipartite graph attention mechanism is introduced to learn the similarity between cells and anchor tokens, bringing cells of the same class closer together in the embedding space. BGFormer achieves linear computational complexity with respect to the number of cells, making it scalable to large datasets. Experimental results on multiple large-scale scRNA-seq datasets demonstrate the effectiveness and scalability of BGFormer.
[759] AI-Driven Predictive Modelling for Groundwater Salinization in Israel
Laxmi Pandey, Ariel Meroz, Ben Cheng, Ankita Manekar, Abhijit Mukherjee, Meirav Cohen, Adway Mitra
Main category: cs.LG
TL;DR: Machine learning framework for groundwater salinity prediction using various models and explainable AI to identify key drivers including meteorological, geological, and anthropogenic factors.
Details
Motivation: Addressing the serious issue of increasing groundwater salinity and contamination worldwide by developing a comprehensive understanding of salinization causes and identifying important drivers.Method: Integrated multiple datasets and applied machine learning models (Random Forest, XGBoost, Neural Network, LSTM, CNN, Linear Regression) with Recursive Feature Elimination, Global Sensitivity Analysis, Explainable AI (SHAP), and Double Machine Learning for causality analysis.
Result: Identified key drivers: meteorological (Precipitation, Temperature), geological (Distance from river, Distance to saline body, TWI, Shoreline distance), and anthropogenic (Area of agriculture field, Treated Wastewater) factors influencing groundwater salinity across Israel.
Conclusion: The approach provides deeper insights into global salinization mechanisms at country scale, reduces AI model uncertainty, and highlights the need for tailored strategies to address salinity, with Treated Wastewater identified as a critical anthropogenic driver.
Abstract: Increasing salinity and contamination of groundwater is a serious issue in many parts of the world, causing degradation of water resources. The aim of this work is to form a comprehensive understanding of groundwater salinization underlying causal factors and identify important meteorological, geological and anthropogenic drivers of salinity. We have integrated different datasets of potential covariates, to create a robust framework for machine learning based predictive models including Random Forest (RF), XGBoost, Neural network, Long Short-Term Memory (LSTM), convolution neural network (CNN) and linear regression (LR), of groundwater salinity. Additionally, Recursive Feature Elimination (RFE) followed by Global sensitivity analysis (GSA) and Explainable AI (XAI) based SHapley Additive exPlanations (SHAP) were used to estimate the importance scores and find insights into the drivers of salinization. We also did causality analysis via Double machine learning using various predictive models. From these analyses, key meteorological (Precipitation, Temperature), geological (Distance from river, Distance to saline body, TWI, Shoreline distance), and anthropogenic (Area of agriculture field, Treated Wastewater) covariates are identified to be influential drivers of groundwater salinity across Israel. XAI analysis also identified Treated Wastewater (TWW) as an essential anthropogenic driver of salinity, its significance being context-dependent but critical in vulnerable hydro-climatic environment. Our approach provides deeper insight into global salinization mechanisms at country scale, reducing AI model uncertainty and highlighting the need for tailored strategies to address salinity.
[760] ODELoRA: Training Low-Rank Adaptation by Solving Ordinary Differential Equations
Yihang Gao, Vincent Y. F. Tan
Main category: cs.LG
TL;DR: ODELoRA: A continuous-time optimization approach for LoRA fine-tuning using ODEs that emulates full fine-tuning on balanced manifolds, improving training stability and convergence.
Details
Motivation: Classical LoRA training treats low-rank factor matrices individually with decoupled optimization, which is suboptimal as it fails to exploit the intrinsic structure of LoRA parameterization. There's a need for more principled optimization methods that can better leverage the mathematical properties of LoRA.Method: Proposes ODELoRA - a continuous-time optimization dynamic for LoRA factor matrices in the form of an ordinary differential equation (ODE) that emulates gradient flow of full fine-tuning on balanced manifolds. Uses time-discretization schemes like Euler and Runge-Kutta methods to track ODE trajectories.
Result: Establishes linear convergence under strongly convex objectives for certain discretization schemes, extends analysis to matrix sensing setting, and shows stable feature learning. Empirical results confirm linear convergence on matrix sensing tasks and demonstrate superiority over baselines in training physics-informed neural networks, especially in training stability.
Conclusion: ODELoRA provides a unified ODE-based perspective for understanding and designing LoRA training algorithms, offering improved optimization properties and training stability compared to classical LoRA methods.
Abstract: Low-rank adaptation (LoRA) has emerged as a widely adopted parameter-efficient fine-tuning method in deep transfer learning, due to its reduced number of trainable parameters and lower memory requirements enabled by Burer-Monteiro factorization on adaptation matrices. However, classical LoRA training methods treat the low-rank factor matrices individually and optimize them using standard gradient-based algorithms. Such decoupled optimization schemes are theoretically and empirically suboptimal, as they fail to fully exploit the intrinsic structure of the LoRA parameterization. In this work, we propose a novel continuous-time optimization dynamic for LoRA factor matrices in the form of an ordinary differential equation (ODE) that emulates the gradient flow of full fine-tuning on the balanced manifold. We term this approach ODELoRA. To faithfully track the trajectories of ODELoRA, we adopt well-established and theoretically grounded time-discretization schemes, including Euler and Runge–Kutta methods. Our framework provides a unified ODE-based perspective for understanding and designing LoRA training algorithms. We establish linear convergence of the proposed method under strongly convex objectives for certain discretization schemes under mild conditions, and further extend our analysis to the matrix sensing setting. Moreover, we show that ODELoRA achieves stable feature learning, a property that is crucial for training deep neural networks at different scales of problem dimensionality. Empirical results on matrix sensing tasks confirm the derived linear convergence behavior, and experiments on training physics-informed neural networks further demonstrate the superiority of ODELoRA over existing baselines, especially in the training stability.
[761] Deriving Neural Scaling Laws from the statistics of natural language
Francesco Cagnetta, Allan Raventós, Surya Ganguli, Matthieu Wyart
Main category: cs.LG
TL;DR: Theory predicts neural scaling law exponents for LLMs using language statistics without free parameters, matching GPT-2/LLaMA training results on TinyStories and WikiText.
Details
Motivation: Existing theories cannot quantitatively predict neural scaling law exponents for modern LLMs trained on natural language, despite these laws guiding empirical progress in large-scale ML.Method: Derives theory based on two key language statistics: (1) decay of pairwise token correlations with time separation, and (2) decay of next-token conditional entropy with context length. Creates parameter-free formula to predict data-limited scaling exponents.
Result: Theory shows remarkable match with experimentally measured neural scaling laws from training GPT-2 and LLaMA style models on TinyStories and WikiText benchmarks.
Conclusion: First theory to quantitatively predict neural scaling exponents for LLMs, using fundamental language statistics without synthetic data models or free parameters.
Abstract: Despite the fact that experimental neural scaling laws have substantially guided empirical progress in large-scale machine learning, no existing theory can quantitatively predict the exponents of these important laws for any modern LLM trained on any natural language dataset. We provide the first such theory in the case of data-limited scaling laws. We isolate two key statistical properties of language that alone can predict neural scaling exponents: (i) the decay of pairwise token correlations with time separation between token pairs, and (ii) the decay of the next-token conditional entropy with the length of the conditioning context. We further derive a simple formula in terms of these statistics that predicts data-limited neural scaling exponents from first principles without any free parameters or synthetic data models. Our theory exhibits a remarkable match with experimentally measured neural scaling laws obtained from training GPT-2 and LLaMA style models from scratch on two qualitatively different benchmarks, TinyStories and WikiText.
[762] Hyperparameter Transfer Laws for Non-Recurrent Multi-Path Neural Networks
Shenxi Wu, Haosong Zhang, Xingjian Ma, Shirui Bian, Yichi Zhang, Xi Chen, Wei Lin
Main category: cs.LG
TL;DR: The paper introduces a graph-based notion of effective depth for multi-path neural networks and shows that optimal learning rates follow a universal -3/2 power law with effective depth under maximal-update parametrization.
Details
Motivation: Modern deep architectures are expensive to train, making hyperparameter transfer crucial. While width scaling is understood via μP, depth scaling for complex architectures with multiple parallel paths and residual connections remains less understood.Method: Introduces graph-based effective depth concept for multi-path networks (CNNs, ResNets, Transformers). Uses maximal-update criterion to maximize one-step representation change without instability. Derives theoretical relationship showing optimal learning rate decays with effective depth following -3/2 power law.
Result: Experiments across diverse architectures confirm the predicted -3/2 power law slope. Enables reliable zero-shot transfer of learning rates across depths and widths, making depth scaling a predictable hyperparameter-transfer problem.
Conclusion: Provides unified framework for understanding depth scaling in modern architectures, enabling predictable hyperparameter transfer and reducing training costs through reliable zero-shot learning rate selection.
Abstract: Deeper modern architectures are costly to train, making hyperparameter transfer preferable to expensive repeated tuning. Maximal Update Parametrization ($μ$P) helps explain why many hyperparameters transfer across width. Yet depth scaling is less understood for modern architectures, whose computation graphs contain multiple parallel paths and residual aggregation. To unify various non-recurrent multi-path neural networks such as CNNs, ResNets, and Transformers, we introduce a graph-based notion of effective depth. Under stabilizing initializations and a maximal-update criterion, we show that the optimal learning rate decays with effective depth following a universal -3/2 power law. Here, the maximal-update criterion maximizes the typical one-step representation change at initialization without causing instability, and effective depth is the minimal path length from input to output, counting layers and residual additions. Experiments across diverse architectures confirm the predicted slope and enable reliable zero-shot transfer of learning rates across depths and widths, turning depth scaling into a predictable hyperparameter-transfer problem.
[763] CoMI-IRL: Contrastive Multi-Intention Inverse Reinforcement Learning
Antonio Mone, Frans A. Oliehoek, Luciano Cavalcante Siebert
Main category: cs.LG
TL;DR: CoMI-IRL is a transformer-based unsupervised framework for multi-intention inverse reinforcement learning that decouples behavior representation/clustering from reward learning, eliminating the need for prior knowledge of the number of behavior modes.
Details
Motivation: Existing deep generative MI-IRL approaches require prior knowledge of the number of true behavioral modes (K*), limiting adaptability to new behaviors and restricting analysis to learned rewards rather than behavior modes.Method: Proposes Contrastive Multi-Intention IRL (CoMI-IRL) using transformer-based unsupervised framework that separates behavior representation and clustering from downstream reward learning, enabling visual interpretation of behavior relationships.
Result: CoMI-IRL outperforms existing approaches without requiring a priori knowledge of K* or labels, allows visual interpretation of behavior relationships, and adapts to unseen behavior without full retraining.
Conclusion: The framework successfully addresses limitations of existing MI-IRL methods by decoupling behavior representation from reward learning, enabling more flexible and interpretable multi-intention inverse reinforcement learning.
Abstract: Inverse Reinforcement Learning (IRL) seeks to infer reward functions from expert demonstrations. When demonstrations originate from multiple experts with different intentions, the problem is known as Multi-Intention IRL (MI-IRL). Recent deep generative MI-IRL approaches couple behavior clustering and reward learning, but typically require prior knowledge of the number of true behavioral modes $K^$. This reliance on expert knowledge limits their adaptability to new behaviors, and only enables analysis related to the learned rewards, and not across the behavior modes used to train them. We propose Contrastive Multi-Intention IRL (CoMI-IRL), a transformer-based unsupervised framework that decouples behavior representation and clustering from downstream reward learning. Our experiments show that CoMI-IRL outperforms existing approaches without a priori knowledge of $K^$ or labels, while allowing for visual interpretation of behavior relationships and adaptation to unseen behavior without full retraining.
[764] PALMS: Pavlovian Associative Learning Models Simulator
Martin Fixman, Alessandro Abati, Julián Jiménez Nimmo, Sean Lim, Esther Mondragón
Main category: cs.LG
TL;DR: PALMS is a Python simulator for Pavlovian conditioning experiments with multiple attentional learning models and configural cue support.
Details
Motivation: To provide a comprehensive simulation environment for Pavlovian associative learning models that enables researchers to test and compare different theoretical approaches in a unified framework.Method: Developed a Python-based simulator with graphical interface that implements Rescorla-Wagner model and several attentional learning approaches (Pearce-Kaye-Hall, Mackintosh Extended, Le Pelley’s Hybrid, and a novel unified variable learning rate extension). Supports complex experimental designs with hundreds of stimuli and configural cues.
Result: Created PALMS simulator with efficient operation, instant visualization, data export capabilities, and open-source licensing. Successfully reproduced published experiments from associative learning literature.
Conclusion: PALMS provides a valuable tool for researchers to simulate, compare, and refine Pavlovian conditioning models, facilitating theory development in associative learning research.
Abstract: Simulations are an indispensable step in the cycle of theory development and refinement, helping researchers formulate precise definitions, generate models, and make accurate predictions. This paper introduces the Pavlovian Associative Learning Models Simulator (PALMS), a Python environment to simulate Pavlovian conditioning experiments. In addition to the canonical Rescorla-Wagner model, PALMS incorporates several attentional learning approaches, including Pearce-Kaye-Hall, Mackintosh Extended, Le Pelley’s Hybrid, and a novel extension of the Rescorla-Wagner model with a unified variable learning rate that integrates Mackintosh’s and Pearce and Hall’s opposing conceptualisations. The simulator’s graphical interface allows for the input of entire experimental designs in an alphanumeric format, akin to that used by experimental neuroscientists. Moreover, it uniquely enables the simulation of experiments involving hundreds of stimuli, as well as the computation of configural cues and configural-cue compounds across all models, thereby considerably expanding their predictive capabilities. PALMS operates efficiently, providing instant visualisation of results, supporting rapid, precise comparisons of various models’ predictions within a single architecture and environment. Furthermore, graphic displays can be easily saved, and simulated data can be exported to spreadsheets. To illustrate the simulator’s capabilities and functionalities, we provide a detailed description of the software and examples of use, reproducing published experiments in the associative learning literature. PALMS is licensed under the open-source GNU Lesser General Public License 3.0. The simulator source code and the latest multiplatform release build are accessible as a GitHub repository at https://github.com/cal-r/PALMS-Simulator
[765] Pareto-guided Pipeline for Distilling Featherweight AI Agents in Mobile MOBA Games
Xionghui Yang, Bozhou Chen, Yunlong Lu, Yongyi Wang, Lingfeng Li, Lanxiao Huang, Lin Liu, Wenjun Wang, Meng Meng, Xia Lin, Wenxin Li
Main category: cs.LG
TL;DR: Mobile deployment of complex game AI agents via Pareto-optimal distillation pipeline and architecture search for efficient on-device execution
Details
Motivation: Deploying powerful game AI agents (like those for Honor of Kings) on mobile devices is challenging due to large policy networks, multi-modal state representation, hierarchical action spaces, and strict mobile constraints (energy, latency, inference frequency).Method: Proposes Pareto optimality guided pipeline with high-efficiency student architecture search space tailored for mobile execution, enabling systematic exploration of performance-efficiency trade-offs through distillation.
Result: Distilled model achieves 12.4× faster inference speed (<0.5ms per frame), 15.6× better energy efficiency (<0.5mAh per game), while retaining 40.32% win rate against original teacher model.
Conclusion: Successfully bridges large-scale game AI with practical on-device deployment through systematic efficiency optimization, demonstrating feasibility of deploying complex AI agents on resource-constrained mobile platforms.
Abstract: Recent advances in game AI have demonstrated the feasibility of training agents that surpass top-tier human professionals in complex environments such as Honor of Kings (HoK), a leading mobile multiplayer online battle arena (MOBA) game. However, deploying such powerful agents on mobile devices remains a major challenge. On one hand, the intricate multi-modal state representation and hierarchical action space of HoK demand large, sophisticated policy networks that are inherently difficult to compress into lightweight forms. On the other hand, production deployment requires high-frequency inference under strict energy and latency constraints on mobile platform. To the best of our knowledge, bridging large-scale game AI and practical on-device deployment has not been systematically studied. In this work, we propose a Pareto optimality guided pipeline and design a high-efficiency student architecture search space tailored for mobile execution, enabling systematic exploration of the trade-off between performance and efficiency. Experimental results demonstrate that the distilled model achieves remarkable efficiency, including an $12.4\times$ faster inference speed (under 0.5ms per frame) and a $15.6\times$ improvement in energy efficiency (under 0.5mAh per game), while retaining a 40.32% win rate against the original teacher model.
[766] MedVerse: Efficient and Reliable Medical Reasoning via DAG-Structured Parallel Execution
Jianwen Chen, Xinyu Yang, Peng Xia, Arian Azarang, Yueh Z Lee, Gang Li, Hongtu Zhu, Yun Li, Beidi Chen, Huaxiu Yao
Main category: cs.LG
TL;DR: MedVerse is a parallel reasoning framework for medical inference that transforms sequential LLM reasoning into parallelizable directed acyclic graphs using Petri net theory, improving efficiency and performance for complex medical tasks.
Details
Motivation: Current LLMs use sequential autoregressive decoding which forces inherently parallel clinical reasoning (like differential diagnosis) into a single linear path, limiting both efficiency and reliability for complex medical problems.Method: Proposes MedVerse framework that reformulates medical reasoning as parallelizable DAGs based on Petri net theory. Includes: 1) MedVerse Curator for automated synthesis of knowledge-grounded reasoning paths into Petri net representations, 2) topology-aware attention mechanism with adaptive position indices for parallel reasoning, and 3) customized inference engine for parallel execution.
Result: Improves strong general-purpose LLMs by up to 8.9%. Achieves comparable performance to specialized medical LLMs while delivering 1.3x reduction in inference latency and 1.7x increase in generation throughput through parallel decoding.
Conclusion: MedVerse demonstrates that parallel reasoning frameworks can significantly improve both performance and efficiency for complex medical inference tasks compared to traditional sequential LLM approaches.
Abstract: Large language models (LLMs) have demonstrated strong performance and rapid progress in a wide range of medical reasoning tasks. However, their sequential autoregressive decoding forces inherently parallel clinical reasoning, such as differential diagnosis, into a single linear reasoning path, limiting both efficiency and reliability for complex medical problems. To address this, we propose MedVerse, a reasoning framework for complex medical inference that reformulates medical reasoning as a parallelizable directed acyclic graph (DAG) process based on Petri net theory. The framework adopts a full-stack design across data, model architecture, and system execution. For data creation, we introduce the MedVerse Curator, an automated pipeline that synthesizes knowledge-grounded medical reasoning paths and transforms them into Petri net-structured representations. At the architectural level, we propose a topology-aware attention mechanism with adaptive position indices that supports parallel reasoning while preserving logical consistency. Systematically, we develop a customized inference engine that supports parallel execution without additional overhead. Empirical evaluations show that MedVerse improves strong general-purpose LLMs by up to 8.9%. Compared to specialized medical LLMs, MedVerse achieves comparable performance while delivering a 1.3x reduction in inference latency and a 1.7x increase in generation throughput, enabled by its parallel decoding capability.
[767] Compact Conformal Subgraphs
Sreenivas Gollapudi, Kostas Kollias, Kamesh Munagala, Aravindan Vijayaraghavan
Main category: cs.LG
TL;DR: Graph-based conformal compression framework for constructing compact subgraphs that preserve statistical validity while reducing structural complexity in structured domains like routing and planning.
Details
Motivation: Conformal prediction provides rigorous uncertainty guarantees but yields prohibitively large prediction sets in structured domains like routing, planning, and sequential recommendation, necessitating compression methods.Method: Formulates compression as selecting smallest subgraph capturing prescribed probability mass, reduces to weighted densest k-subgraphs in hypergraphs, designs efficient approximation algorithms with constant factor coverage/size trade-offs, and proves monotonicity property via connection to parametric minimum cuts.
Result: Develops efficient approximation algorithms that achieve constant factor coverage and size trade-offs, proves monotonicity property ensures nestedness for valid conformal guarantees, and validates approach via simulations for trip planning and navigation.
Conclusion: Bridges efficient conformal prediction with combinatorial graph compression via monotonicity to provide rigorous guarantees on both statistical validity and compression, while identifying algorithmic regime distinct from classical densest-k-subgraph hardness settings.
Abstract: Conformal prediction provides rigorous, distribution-free uncertainty guarantees, but often yields prohibitively large prediction sets in structured domains such as routing, planning, or sequential recommendation. We introduce “graph-based conformal compression”, a framework for constructing compact subgraphs that preserve statistical validity while reducing structural complexity. We formulate compression as selecting a smallest subgraph capturing a prescribed fraction of the probability mass, and reduce to a weighted version of densest $k$-subgraphs in hypergraphs, in the regime where the subgraph has a large fraction of edges. We design efficient approximation algorithms that achieve constant factor coverage and size trade-offs. Crucially, we prove that our relaxation satisfies a monotonicity property, derived from a connection to parametric minimum cuts, which guarantees the nestedness required for valid conformal guarantees. Our results on the one hand bridge efficient conformal prediction with combinatorial graph compression via monotonicity, to provide rigorous guarantees on both statistical validity, and compression or size. On the other hand, they also highlight an algorithmic regime, distinct from classical densest-$k$-subgraph hardness settings, where the problem can be approximated efficiently. We finally validate our algorithmic approach via simulations for trip planning and navigation, and compare to natural baselines.
[768] Gaussian Match-and-Copy: A Minimalist Benchmark for Studying Transformer Induction
Antoine Gonon, Alexandre Cordonnier, Nicolas Boumal
Main category: cs.LG
TL;DR: Transformers develop match-and-copy retrieval circuits through gradient descent’s implicit bias toward max-margin solutions, even when other solutions exist.
Details
Motivation: To understand how match-and-copy retrieval emerges in LLMs by disentangling retrieval from memorization, since natural data entangles these behaviors.Method: Introduce Gaussian Match-and-Copy (GMC) benchmark with pure second-order correlation signals to isolate long-range retrieval. Analyze optimization dynamics in simplified attention settings and prove max-margin alignment for gradient descent trajectories.
Result: GMC retains key qualitative aspects of how Transformers develop match-and-copy circuits in practice and separates architectures by retrieval capabilities. Gradient descent drives parameters to diverge while aligning with max-margin separator, yielding hard match selection.
Conclusion: Match-and-copy retrieval emerges from gradient descent’s implicit bias toward max-margin solutions rather than being explicitly designed, providing theoretical understanding of this core LLM inference primitive.
Abstract: Match-and-copy is a core retrieval primitive used at inference time by large language models to retrieve a matching token from the context then copy its successor. Yet, understanding how this behavior emerges on natural data is challenging because retrieval and memorization are entangled. To disentangle the two, we introduce Gaussian Match-and-Copy (GMC), a minimalist benchmark that isolates long-range retrieval through pure second-order correlation signals. Numerical investigations show that this task retains key qualitative aspects of how Transformers develop match-and-copy circuits in practice, and separates architectures by their retrieval capabilities. We also analyze the optimization dynamics in a simplified attention setting. Although many solutions are a priori possible under a regression objective, including ones that do not implement retrieval, we identify an implicit-bias regime in which gradient descent drives the parameters to diverge while their direction aligns with the max-margin separator, yielding hard match selection. We prove this max-margin alignment for GD trajectories that reach vanishing empirical loss under explicit technical conditions.
[769] Enhancing Time Series Classification with Diversity-Driven Neural Network Ensembles
Javidan Abdullayev, Maxime Devanne, Cyril Meyer, Ali Ismail-Fawaz, Jonathan Weber, Germain Forestier
Main category: cs.LG
TL;DR: A diversity-driven ensemble learning framework for time series classification that explicitly encourages feature diversity among neural network ensemble members using decorrelated learning and feature orthogonality loss.
Details
Motivation: Existing neural network-based ensemble methods for time series classification typically train multiple models with identical architectures and configurations, leading to redundant feature representations that limit the benefits of ensembling. The paper aims to address this by promoting explicit diversity among ensemble members.Method: The framework employs a decorrelated learning strategy using a feature orthogonality loss applied directly to learned feature representations. This ensures each model captures complementary rather than redundant information, promoting diversity among ensemble members.
Result: The method achieves state-of-the-art performance on 128 datasets from the UCR archive with fewer models compared to conventional neural network-based ensemble approaches, making it both efficient and scalable.
Conclusion: Explicitly encouraging feature diversity through decorrelated learning significantly improves ensemble performance in time series classification, achieving better results with fewer models than traditional ensemble methods.
Abstract: Ensemble methods have played a crucial role in achieving state-of-the-art (SOTA) performance across various machine learning tasks by leveraging the diversity of features learned by individual models. In Time Series Classification (TSC), ensembles have proven highly effective whether based on neural networks (NNs) or traditional methods like HIVE-COTE. However most existing NN-based ensemble methods for TSC train multiple models with identical architectures and configurations. These ensembles aggregate predictions without explicitly promoting diversity which often leads to redundant feature representations and limits the benefits of ensembling. In this work, we introduce a diversity-driven ensemble learning framework that explicitly encourages feature diversity among neural network ensemble members. Our approach employs a decorrelated learning strategy using a feature orthogonality loss applied directly to the learned feature representations. This ensures that each model in the ensemble captures complementary rather than redundant information. We evaluate our framework on 128 datasets from the UCR archive and show that it achieves SOTA performance with fewer models. This makes our method both efficient and scalable compared to conventional NN-based ensemble approaches.
[770] Unified Biomolecular Trajectory Generation via Pretrained Variational Bridge
Ziyang Yu, Wenbing Huang, Yang Liu
Main category: cs.LG
TL;DR: PVB is a pretrained variational bridge model that learns molecular dynamics at coarsened timesteps using encoder-decoder architecture with bridge matching, enabling efficient trajectory generation for proteins and protein-ligand complexes.
Details
Motivation: MD simulations are computationally expensive, and existing deep generative models for learning dynamics at coarsened timesteps either generalize poorly across systems or fail to fully exploit structural information due to limited molecular diversity in trajectory data.Method: Pretrained Variational Bridge (PVB) uses encoder-decoder architecture to map initial structures into noised latent space and transports them toward stage-specific targets through augmented bridge matching. For protein-ligand complexes, it introduces reinforcement learning-based optimization via adjoint matching to speed progression toward holo state.
Result: PVB faithfully reproduces thermodynamic and kinetic observables from MD while delivering stable and efficient generative dynamics for proteins and protein-ligand complexes.
Conclusion: PVB provides an effective approach for efficient molecular dynamics generation that unifies training on both single-structure and paired trajectory data, enabling consistent use of cross-domain structural knowledge and supporting post-optimization of docking poses.
Abstract: Molecular Dynamics (MD) simulations provide a fundamental tool for characterizing molecular behavior at full atomic resolution, but their applicability is severely constrained by the computational cost. To address this, a surge of deep generative models has recently emerged to learn dynamics at coarsened timesteps for efficient trajectory generation, yet they either generalize poorly across systems or, due to limited molecular diversity of trajectory data, fail to fully exploit structural information to improve generative fidelity. Here, we present the Pretrained Variational Bridge (PVB) in an encoder-decoder fashion, which maps the initial structure into a noised latent space and transports it toward stage-specific targets through augmented bridge matching. This unifies training on both single-structure and paired trajectory data, enabling consistent use of cross-domain structural knowledge across training stages. Moreover, for protein-ligand complexes, we further introduce a reinforcement learning-based optimization via adjoint matching that speeds progression toward the holo state, which supports efficient post-optimization of docking poses. Experiments on proteins and protein-ligand complexes demonstrate that PVB faithfully reproduces thermodynamic and kinetic observables from MD while delivering stable and efficient generative dynamics.
[771] Beyond Arrow: From Impossibility to Possibilities in Multi-Criteria Benchmarking
Polina Gordienko, Christoph Jansen, Julian Rodemann, Georg Schollmeyer
Main category: cs.LG
TL;DR: The paper formalizes multi-metric benchmarking as a social choice problem and identifies conditions under which coherent model rankings can be constructed despite Arrow’s impossibility theorem.
Details
Motivation: Modern benchmarks like HELM MMLU use multiple metrics (accuracy, robustness, efficiency), but aggregating these into a single ranking can lead to incoherent or unstable results. The authors want to understand when meaningful multi-criteria benchmarking is possible despite Arrow's impossibility theorem.Method: Formalize benchmarking as a social choice problem where each metric induces a preference ranking over models on each dataset. Analyze three restrictions on preference combinations: single-peaked, group-separable, and distance-restricted preferences. Prove that under these conditions, well-behaved rankings can be constructed. Empirically investigate modern benchmark suites like HELM MMLU to verify which structural conditions are fulfilled.
Result: The paper shows that while Arrow’s impossibility theorem suggests aggregation problems, meaningful multi-criteria benchmarking becomes possible under certain structural conditions on preferences. The authors prove that on single-peaked, group-separable and distance-restricted preferences, benchmark operators can construct coherent model rankings.
Conclusion: Pathological examples that lead to Arrow’s impossibility can be avoided through structural restrictions on preferences, enabling practical and coherent multi-metric benchmarking in real-world scenarios like HELM MMLU.
Abstract: Modern benchmarks such as HELM MMLU account for multiple metrics like accuracy, robustness and efficiency. When trying to turn these metrics into a single ranking, natural aggregation procedures can become incoherent or unstable to changes in the model set. We formalize this aggregation as a social choice problem where each metric induces a preference ranking over models on each dataset, and a benchmark operator aggregates these votes across metrics. While prior work has focused on Arrow’s impossibility result, we argue that the impossibility often originates from pathological examples and identify sufficient conditions under which these disappear, and meaningful multi-criteria benchmarking becomes possible. In particular, we deal with three restrictions on the combinations of rankings and prove that on single-peaked, group-separable and distance-restricted preferences, the benchmark operator allows for the construction of well-behaved rankings of the involved models. Empirically, we investigate several modern benchmark suites like HELM MMLU and verify which structural conditions are fulfilled on which benchmark problems.
[772] Astro: Activation-guided Structured Regularization for Outlier-Robust LLM Post-Training Quantization
Xi Chen, Ming Li, Junxi Li, Changsheng Li, Peisong Wang, Lizhong Ding, Ye Yuan, Guoren Wang
Main category: cs.LG
TL;DR: Astro is an activation-guided structured regularization framework for weight-only post-training quantization of LLMs that suppresses weight outliers without adding inference latency.
Details
Motivation: Weight-only PTQ suffers from accuracy degradation due to weight and activation outliers. Existing solutions have limitations: insufficient outlier suppression or deployment inefficiencies like inference latency, heavy preprocessing, or complex operator fusion.Method: Leverages insight that over-parameterized LLMs converge to Flat Minima, allowing weight adjustment without accuracy loss. Uses activation-guided structured regularization to reconstruct robust weights, suppressing weight outliers corresponding to high-magnitude activations. Zero inference latency and orthogonal to mainstream quantization methods like GPTQ.
Result: Achieves highly competitive performance; on LLaMA-2-7B, achieves better performance than complex learning-based rotation methods with almost 1/3 of the quantization time.
Conclusion: Astro provides an efficient, hardware-friendly solution for suppressing outliers in weight-only PTQ without inference overhead, making LLM deployment more practical.
Abstract: Weight-only post-training quantization (PTQ) is crucial for efficient Large Language Model (LLM) deployment but suffers from accuracy degradation caused by weight and activation outliers. Existing mitigation strategies often face critical limitations: they either yield insufficient outlier suppression or incur significant deployment inefficiencies, such as inference latency, heavy preprocessing, or reliance on complex operator fusion. To resolve these limitations, we leverage a key insight: over-parameterized LLMs often converge to Flat Minima, implying a vast equivalent solution space where weights can be adjusted without compromising accuracy. Building on this, we propose Astro, an Activation-guided Structured Regularization framework designed to suppress the negative effects of outliers in a hardware-friendly and efficient manner. Leveraging the activation-guided regularization objective, Astro actively reconstructs intrinsically robust weights, aggressively suppressing weight outliers corresponding to high-magnitude activations without sacrificing model accuracy. Crucially, Astro introduces zero inference latency and is orthogonal to mainstream quantization methods like GPTQ. Extensive experiments show that Astro achieves highly competitive performance; notably, on LLaMA-2-7B, it achieves better performance than complex learning-based rotation methods with almost 1/3 of the quantization time.
[773] Rational Transductors
Mehryar Mohri
Main category: cs.LG
TL;DR: Rational Transductors augment Transformers with Weighted Finite Automata recurrence to capture regular languages and NC¹ problems, solving Transformers’ limitations on sequential logic while maintaining parallel efficiency.
Details
Motivation: Transformers struggle with rigid sequential logic, state tracking, and length generalization due to self-attention's computational complexity limitations (AC⁰/TC⁰). They fail on fundamental problems like parity, modular counting, and regular language recognition without intermediate chain-of-thought reasoning.Method: Dual-stream architecture combining Transformer with matrix-valued recurrence from Weighted Finite Automata. Uses Deep Rational Injection to inject rational state information into attention mechanism. Employs Random Rational Features as universal basis for sequential dependencies and Differentiable Rational Feature regime to close representational gap.
Result: Theoretically generalizes Transformer expressive power to capture all Regular Languages, NC¹-complete problems (Boolean Formula Evaluation), and fundamental separations like Parity and Modular Counting. Maintains O(L + log T) parallel time complexity. Empirically solves the “Regular Gap” enabling robust length generalization on algorithmic tasks where standard Transformers fail.
Conclusion: Rational Transductors bridge the gap between Transformers’ semantic modeling strengths and sequential reasoning limitations, providing a theoretically grounded architecture that captures regular languages and complex sequential patterns while preserving parallel efficiency.
Abstract: Standard Transformers excel at semantic modeling but struggle with rigid sequential logic and state tracking. Theoretical work establishes that self-attention is limited to $\AC^0$ (under hard attention) or $\TC^0$ (under soft attention), complexity classes that often fail to support robust length generalization on sequential problems without intermediate chain-of-thought. In this work, we introduce \emph{Rational Transductors}, a dual-stream architecture that augments the Transformer with a matrix-valued recurrence derived from Weighted Finite Automata (WFA). By injecting rational state information into the attention mechanism via a \emph{Deep Rational Injection} scheme, our framework strictly generalizes the expressive power of Transformers to capture all Regular Languages, $\NC^1$-complete problems (such as Boolean Formula Evaluation), and fundamental separations like Parity and Modular Counting, while preserving $O(L + \log T)$ parallel time complexity. We ground the architecture in a rigorous learning theory: we prove that \emph{Random Rational Features} act as a universal basis for sequential dependencies, justifying our initialization strategy, while establishing that the \emph{Differentiable Rational Feature} regime is necessary to close the representational compactness gap. Theoretical analysis and empirical results demonstrate that Rational Transductors solve the “Regular Gap,” enabling robust length generalization on algorithmic tasks where standard Transformers fail, without the sequential computational bottlenecks of traditional RNNs.
[774] Object-Oriented Transition Modeling with Inductive Logic Programming
Gabriel Stella, Dmitri Loguinov
Main category: cs.LG
TL;DR: A novel learning algorithm for object-oriented representations that significantly outperforms previous methods and neural baselines in terms of generalization, interpretability, and training efficiency.
Details
Motivation: The paper addresses the challenge of building accurate, generalizable, interpretable, and efficiently trainable world models from observation (induction). It builds on prior work in object-oriented representations inspired by human cognition but aims to develop a substantially more powerful approach.Method: Develops a novel learning algorithm for object-oriented representations that improves upon previous methods. The approach includes thorough experiments with ablation tests and comparisons with neural baselines.
Result: Demonstrates significant improvement over state-of-the-art methods in terms of generalization, interpretability, and training efficiency through comprehensive experimental evaluation.
Conclusion: The proposed learning algorithm represents a substantial advancement in object-oriented representation learning, offering better generalization, interpretability, and training efficiency compared to existing approaches.
Abstract: Building models of the world from observation, i.e., induction, is one of the major challenges in machine learning. In order to be useful, models need to maintain accuracy when used in novel situations, i.e., generalize. In addition, they should be easy to interpret and efficient to train. Prior work has investigated these concepts in the context of object-oriented representations inspired by human cognition. In this paper, we develop a novel learning algorithm that is substantially more powerful than these previous methods. Our thorough experiments, including ablation tests and comparison with neural baselines, demonstrate a significant improvement over the state-of-the-art.
[775] Escaping Spectral Bias without Backpropagation: Fast Implicit Neural Representations with Extreme Learning Machines
Woojin Cho, Junghwan Park
Main category: cs.LG
TL;DR: ELM-INR: A backpropagation-free implicit neural representation method using Extreme Learning Machines with local subdomain decomposition and adaptive mesh refinement for handling non-uniform frequency content.
Details
Motivation: Traditional implicit neural representations (INRs) suffer from spectral bias and slow iterative optimization when dealing with highly non-uniform frequency content. The authors aim to develop a faster, more stable alternative that avoids backpropagation while maintaining reconstruction quality.Method: Proposes ELM-INR which decomposes the domain into overlapping subdomains and fits each local problem using Extreme Learning Machines (ELMs) in closed form via linear least-squares solutions. Combines local predictors through partition of unity. Introduces BEAM, an adaptive mesh refinement strategy based on spectral Barron norm analysis to balance spectral complexity across subdomains.
Result: The method achieves fast and numerically robust reconstruction by replacing iterative optimization with stable linear solutions. The adaptive refinement strategy improves reconstruction quality in capacity-constrained regimes by addressing regions with high spectral complexity.
Conclusion: ELM-INR provides an efficient, backpropagation-free alternative for training implicit neural representations that handles non-uniform frequency content better than traditional methods, with theoretical grounding in spectral analysis and practical adaptive refinement.
Abstract: Training implicit neural representations (INRs) to capture fine-scale details typically relies on iterative backpropagation and is often hindered by spectral bias when the target exhibits highly non-uniform frequency content. We propose ELM-INR, a backpropagation-free INR that decomposes the domain into overlapping subdomains and fits each local problem using an Extreme Learning Machine (ELM) in closed form, replacing iterative optimization with stable linear least-squares solutions. This design yields fast and numerically robust reconstruction by combining local predictors through a partition of unity. To understand where approximation becomes difficult under fixed local capacity, we analyze the method from a spectral Barron norm perspective, which reveals that global reconstruction error is dominated by regions with high spectral complexity. Building on this insight, we introduce BEAM, an adaptive mesh refinement strategy that balances spectral complexity across subdomains to improve reconstruction quality in capacity-constrained regimes.
[776] SERE: Similarity-based Expert Re-routing for Efficient Batch Decoding in MoE Models
Juntong Wu, Jialiang Cheng, Fuyu Lv, Ou Dan, Li Yuan
Main category: cs.LG
TL;DR: SERE is a similarity-based expert re-routing method for efficient batch decoding in Mixture-of-Experts models that dynamically reduces active experts by re-routing tokens from secondary to primary experts, achieving up to 2.0x speedup with minimal quality loss.
Details
Motivation: MoE models require batch inference for hardware efficiency in production serving, but this causes excessive expert activation that slows down the memory-bound decoding stage, creating a tension between batch decoding and expert sparsity.Method: SERE dynamically reduces active experts in an input-aware manner by re-routing tokens from secondary experts to their most similar primary counterparts. It identifies and preserves critical experts using similarity patterns, avoids static pruning/merging, and includes an efficient custom CUDA kernel for plug-and-play use in vLLM.
Result: Extensive experiments on various complex reasoning benchmarks show SERE achieves up to 2.0x speedup with minimal quality loss, providing practical solution for cost-efficient and latency-sensitive large-scale MoE deployment.
Conclusion: SERE addresses the fundamental tension between batch decoding and expert sparsity in MoE models through dynamic similarity-based expert re-routing, enabling efficient batch inference with minimal capability loss.
Abstract: Mixture-of-Experts (MoE) architectures employ sparse activation to deliver faster training and inference with higher accuracy than dense LLMs. However, in production serving, MoE models require batch inference to optimize hardware efficiency, which may cause excessive expert activation and thus slow the memory-bound decoding stage. To address the fundamental tension between batch decoding and expert sparsity, we present SERE, a Similarity-based Expert Re-routing method for Efficient batch decoding in MoE models. SERE dynamically reduces the number of active experts in an input-aware manner by re-routing tokens from secondary experts to their most similar primary counterparts. It also leverages similarity patterns to identify and preserve critical experts, thereby preventing capability loss. Notably, SERE avoids static expert pruning or merging, instead enabling dynamic expert skipping based on batch-level expert redundancy. Additionally, we provide an efficient custom CUDA kernel for SERE, enabling plug-and-play use in vLLM with only a single-line code change. Extensive experiments on various complex reasoning benchmarks demonstrate that SERE achieves up to 2.0x speedup with minimal quality loss, providing a practical solution for cost-efficient and latency-sensitive large-scale MoE deployment. Code implementation of SERE can be found in https://github.com/JL-Cheng/SERE.
[777] Dense Neural Networks are not Universal Approximators
Levi Rauchwerger, Stefanie Jegelka, Ron Levie
Main category: cs.LG
TL;DR: Dense neural networks lack universal approximation capabilities under natural weight constraints, unlike sparse networks which can achieve true universality.
Details
Motivation: To investigate the fundamental limitations of dense neural networks and understand whether the universal approximation theorems hold under practical constraints on weights and connectivity.Method: Uses model compression approach combining weak regularity lemma with interpretation of feedforward networks as message passing graph neural networks, analyzing ReLU networks with natural weight constraints and dense connectivity.
Result: Demonstrates existence of Lipschitz continuous functions that cannot be approximated by dense neural networks under natural constraints, showing intrinsic limitations of dense connectivity.
Conclusion: Dense neural networks do not possess universality under practical constraints, motivating the use of sparse connectivity as necessary for achieving true universal approximation capabilities.
Abstract: We investigate the approximation capabilities of dense neural networks. While universal approximation theorems establish that sufficiently large architectures can approximate arbitrary continuous functions if there are no restrictions on the weight values, we show that dense neural networks do not possess this universality. Our argument is based on a model compression approach, combining the weak regularity lemma with an interpretation of feedforward networks as message passing graph neural networks. We consider ReLU neural networks subject to natural constraints on weights and input and output dimensions, which model a notion of dense connectivity. Within this setting, we demonstrate the existence of Lipschitz continuous functions that cannot be approximated by such networks. This highlights intrinsic limitations of neural networks with dense layers and motivates the use of sparse connectivity as a necessary ingredient for achieving true universality.
[778] TASTE: Task-Aware Out-of-Distribution Detection via Stein Operators
Michał Kozyra, Gesine Reinert
Main category: cs.LG
TL;DR: TASTE framework uses Stein operators to link distribution shifts to model sensitivity, providing both detection and localization of out-of-distribution data with theoretical guarantees.
Details
Motivation: Current OOD detection methods are either data-centric (detecting input distribution deviations) or model-centric (relying on classifier outputs), but lack a unified approach that connects distribution shifts to model sensitivity and task performance.Method: Proposes TASTE (Task-Aware STEin operators) framework based on Stein operators that links distribution shift to input sensitivity of models. The operator provides geometric interpretation as projection of distribution shift onto model’s sensitivity field, enabling both detection and localization of shifts.
Result: Experiments on Gaussian shifts, MNIST under geometric perturbations, and CIFAR-10 benchmarks show the method aligns closely with task degradation and outperforms established baselines. Provides interpretable per-pixel diagnostics for image data.
Conclusion: TASTE offers a principled framework connecting distribution shifts to model sensitivity with theoretical guarantees, enabling both detection and localization of OOD data while maintaining task-awareness.
Abstract: Out-of-distribution detection methods are often either data-centric, detecting deviations from the training input distribution irrespective of their effect on a trained model, or model-centric, relying on classifier outputs without explicit reference to data geometry. We propose TASTE (Task-Aware STEin operators): a task-aware framework based on so-called Stein operators, which allows us to link distribution shift to the input sensitivity of the model. We show that the resulting operator admits a clear geometric interpretation as a projection of distribution shift onto the sensitivity field of the model, yielding theoretical guarantees. Beyond detecting the presence of a shift, the same construction enables its localisation through a coordinate-wise decomposition, and for image data-provides interpretable per-pixel diagnostics. Experiments on controlled Gaussian shifts, MNIST under geometric perturbations, and CIFAR-10 perturbed benchmarks demonstrate that the proposed method aligns closely with task degradation while outperforming established baselines.
[779] Continuous Program Search
Matthew Siper, Muhammad Umair Nasir, Ahmed Khalifa, Lisa Soros, Jay Azhang, Julian Togelius
Main category: cs.LG
TL;DR: Genetic Programming with learned continuous program embeddings and geometry-compiled mutation operators improves search efficiency by maintaining behavioral locality.
Details
Motivation: Traditional Genetic Programming suffers from poor locality - small syntactic mutations cause large behavioral changes, degrading sample efficiency. The paper aims to design mutation operators that exploit learned continuous program spaces where latent distance correlates with behavioral similarity.Method: Learn a continuous program embedding space where latent distance has behavioral meaning. Track action-level divergence under latent perturbations to identify empirical trust regions. Use a compact trading-strategy DSL with four semantic components. Compare isotropic Gaussian mutation to geometry-compiled mutation that restricts updates to semantically paired entry-exit subspaces using a learned flow-based model trained on logged mutation outcomes.
Result: Learned mutation operator discovers strong strategies using an order of magnitude fewer evaluations and achieves highest median out-of-sample Sharpe ratio across five assets. Geometry-compiled mutation yields faster, more reliable progress compared to isotropic mutation.
Conclusion: Semantically aligned mutation can substantially improve search efficiency in Genetic Programming without modifying the underlying evolutionary algorithm, by exploiting learned continuous program embeddings that maintain behavioral locality.
Abstract: Genetic Programming yields interpretable programs, but small syntactic mutations can induce large, unpredictable behavioral shifts, degrading locality and sample efficiency. We frame this as an operator-design problem: learn a continuous program space where latent distance has behavioral meaning, then design mutation operators that exploit this structure without changing the evolutionary optimizer. We make locality measurable by tracking action-level divergence under controlled latent perturbations, identifying an empirical trust region for behavior-local continuous variation. Using a compact trading-strategy DSL with four semantic components (long/short entry and exit), we learn a matching block-factorized embedding and compare isotropic Gaussian mutation over the full latent space to geometry-compiled mutation that restricts updates to semantically paired entry–exit subspaces and proposes directions using a learned flow-based model trained on logged mutation outcomes. Under identical $(μ+λ)$ evolution strategies and fixed evaluation budgets across five assets, the learned mutation operator discovers strong strategies using an order of magnitude fewer evaluations and achieves the highest median out-of-sample Sharpe ratio. Although isotropic mutation occasionally attains higher peak performance, geometry-compiled mutation yields faster, more reliable progress, demonstrating that semantically aligned mutation can substantially improve search efficiency without modifying the underlying evolutionary algorithm.
[780] Surprisal-Guided Selection: Compute-Optimal Test-Time Strategies for Execution-Grounded Code Generation
Jarrod Barnes
Main category: cs.LG
TL;DR: Test-time training underperforms search strategies for verifiable execution-grounded tasks; surprisal-guided selection of low-confidence correct samples achieves near-oracle performance.
Details
Motivation: To determine whether gradient-based adaptation (test-time training) or search strategies are more effective for verifiable execution-grounded tasks with dense reward signals, particularly in domains like GPU kernel optimization.Method: Used KernelBench as testbed with 120B-parameter model; compared test-time training (1-5 gradient steps) vs. search (Best-of-N sampling); introduced surprisal-guided selection that chooses highest-surprisal (lowest-confidence) correct samples.
Result: Search (Best-of-N with K=64) achieved 90% task success vs. TTT’s 30.6%; surprisal-guided selection yielded 80% success vs. 50% for most-confident selection; surprisal-guided-top3 matched oracle performance at 100%.
Conclusion: For dense-reward VEG tasks, compute should prioritize sample diversity and intelligent selection over gradient adaptation; surprisal-guided selection effectively recovers oracle performance and may generalize to other execution-grounded domains.
Abstract: Test-time training (TTT) adapts language models through gradient-based updates at inference. But is adaptation the right strategy? We study compute-optimal test-time strategies for verifiable execution-grounded (VEG) tasks, domains like GPU kernel optimization where a deterministic evaluator provides dense, continuous reward signals. Using KernelBench as our testbed and a 120B-parameter model (GPT-OSS-120B with LoRA adaptation), we find that search outperforms minimal adaptation (1-5 gradient steps): Best-of-N sampling achieves 90% task success (18/20 tasks) at K=64 across the full KernelBench L1 eval set while TTT’s best checkpoint reaches only 30.6% (3-seed mean), with TTT’s “equivalent K” falling below 1, worse than single-sample inference. The failure mode is over-sharpening: gradient updates collapse diversity toward mediocre solutions rather than discovering optimal ones. Our main contribution is surprisal-guided selection: selecting the highest-surprisal (lowest-confidence) correct sample yields 80% success vs. 50% for most-confident selection, a 30% improvement. Extending to surprisal-guided-top3 matches oracle performance at 100%. This zero-cost strategy, validated through length-controlled analysis, recovers oracle performance. For dense-reward VEG tasks, compute should be allocated to sample diversity and intelligent selection rather than gradient adaptation. The surprisal-guided selection principle may generalize to other execution-grounded domains where optimal solutions occupy the distribution tail.
[781] Federated Learning with Profile Mapping under Distribution Shifts and Drifts
Mohan Li, Dario Fenoglio, Martin Gjoreski, Marc Langheinrich
Main category: cs.LG
TL;DR: Feroma is a federated learning framework that handles both distribution shift across clients and distribution drift over time using client distribution profiles, without needing client/cluster identities or retraining for new clients.
Details
Motivation: Federated learning performance degrades under real-world data heterogeneity (distribution shift across clients and drift over time). Existing methods fail to address both issues simultaneously or rely on unrealistic assumptions like known client clusters and data heterogeneity types, limiting generalizability.Method: Uses client distribution profiles - compact, privacy-preserving representations of local data - to guide model aggregation and test-time model assignment through adaptive similarity-based weighting. Dynamically selects aggregation strategies (from clustered to personalized) during training and deploys suitable models to unseen test clients without retraining or online adaptation.
Result: Extensive experiments show Feroma outperforms 10 state-of-the-art methods with average accuracy gains up to 12 percentage points across 6 benchmarks, while maintaining computational/communication overhead comparable to FedAvg. Improves performance and stability under dynamic data heterogeneity conditions.
Conclusion: Distribution-profile-based aggregation offers a practical path toward robust federated learning under both data distribution shifts and drifts, without relying on unrealistic assumptions about client identities or data heterogeneity.
Abstract: Federated Learning (FL) enables decentralized model training across clients without sharing raw data, but its performance degrades under real-world data heterogeneity. Existing methods often fail to address distribution shift across clients and distribution drift over time, or they rely on unrealistic assumptions such as known number of client clusters and data heterogeneity types, which limits their generalizability. We introduce Feroma, a novel FL framework that explicitly handles both distribution shift and drift without relying on client or cluster identity. Feroma builds on client distribution profiles-compact, privacy-preserving representations of local data-that guide model aggregation and test-time model assignment through adaptive similarity-based weighting. This design allows Feroma to dynamically select aggregation strategies during training, ranging from clustered to personalized, and deploy suitable models to unseen, and unlabeled test clients without retraining, online adaptation, or prior knowledge on clients’ data. Extensive experiments show that compared to 10 state-of-the-art methods, Feroma improves performance and stability under dynamic data heterogeneity conditions-an average accuracy gain of up to 12 percentage points over the best baselines across 6 benchmarks-while maintaining computational and communication overhead comparable to FedAvg. These results highlight that distribution-profile-based aggregation offers a practical path toward robust FL under both data distribution shifts and drifts.
[782] ElliCE: Efficient and Provably Robust Algorithmic Recourse via the Rashomon Sets
Bohdan Turbal, Iryna Voitsitska, Lesia Semenova
Main category: cs.LG
TL;DR: ElliCE is a framework for robust algorithmic recourse that generates counterfactual explanations valid across multiple near-optimal models in the Rashomon set, addressing reliability issues when models are uncertain.
Details
Motivation: When machine learning models affect people's lives, it's important to provide actionable recourse suggestions. Standard counterfactual explanations become unreliable when there are many near-optimal models (Rashomon set), as recourse valid for one model may fail under another.Method: ElliCE optimizes counterfactuals over an ellipsoidal approximation of the Rashomon set, providing provably valid explanations with theoretical guarantees on uniqueness, stability, and alignment with key feature directions.
Result: Empirically, ElliCE generates more robust and flexible counterfactuals that adapt to user-specified feature constraints while being substantially faster than existing baselines.
Conclusion: ElliCE provides a principled and practical solution for reliable recourse under model uncertainty, ensuring stable recommendations for users even as models evolve.
Abstract: Machine learning models now influence decisions that directly affect people’s lives, making it important to understand not only their predictions, but also how individuals could act to obtain better results. Algorithmic recourse provides actionable input modifications to achieve more favorable outcomes, typically relying on counterfactual explanations to suggest such changes. However, when the Rashomon set - the set of near-optimal models - is large, standard counterfactual explanations can become unreliable, as a recourse action valid for one model may fail under another. We introduce ElliCE, a novel framework for robust algorithmic recourse that optimizes counterfactuals over an ellipsoidal approximation of the Rashomon set. The resulting explanations are provably valid over this ellipsoid, with theoretical guarantees on uniqueness, stability, and alignment with key feature directions. Empirically, ElliCE generates counterfactuals that are not only more robust but also more flexible, adapting to user-specified feature constraints while being substantially faster than existing baselines. This provides a principled and practical solution for reliable recourse under model uncertainty, ensuring stable recommendations for users even as models evolve.
[783] Spectral Gating Networks
Jusheng Zhang, Yijia Fan, Kaitong Cai, Jing Yang, Yongsen Zheng, Kwok-Yan Lam, Liang Lin, Keze Wang
Main category: cs.LG
TL;DR: Spectral Gating Networks (SGN) introduce a stable spectral reparameterization for MLPs that enhances frequency-rich expressivity without sacrificing stability or scalability, outperforming spline-based approaches across multimodal tasks.
Details
Motivation: To address the tension between introducing frequency-rich expressivity in feed-forward networks and maintaining stability/scalability, particularly in spline-based KAN parameterizations where grid refinement causes parameter growth and brittle optimization in high dimensions.Method: SGN augments standard activation pathways with compact spectral pathways using trainable Random Fourier Features (learned frequencies and phases) instead of grid-based splines, plus learnable gates that allow progressive allocation of capacity to spectral features during training. Uses hybrid GELU-Fourier formulation for optimization robustness.
Result: Achieves 93.15% accuracy on CIFAR-10 and up to 11.7x faster inference than spline-based KAN variants. Consistently improves accuracy-efficiency trade-offs across vision, NLP, audio, and PDE benchmarks under comparable computational budgets.
Conclusion: SGN provides a stable, scalable way to inject spectral capacity into existing MLP/FFN layers without increasing parameter/training budgets, offering better optimization properties than spline-based approaches while maintaining high-frequency fidelity.
Abstract: Gating mechanisms are ubiquitous, yet a complementary question in feed-forward networks remains under-explored: how to introduce frequency-rich expressivity without sacrificing stability and scalability? This tension is exposed by spline-based Kolmogorov-Arnold Network (KAN) parameterizations, where grid refinement can induce parameter growth and brittle optimization in high dimensions. To propose a stability-preserving way to inject spectral capacity into existing MLP/FFN layers under fixed parameter and training budgets, we introduce Spectral Gating Networks (SGN), a drop-in spectral reparameterization. SGN augments a standard activation pathway with a compact spectral pathway and learnable gates that allow the model to start from a stable base behavior and progressively allocate capacity to spectral features during training. The spectral pathway is instantiated with trainable Random Fourier Features (learned frequencies and phases), replacing grid-based splines and removing resolution dependence. A hybrid GELU-Fourier formulation further improves optimization robustness while enhancing high-frequency fidelity. Across vision, NLP, audio, and PDE benchmarks, SGN consistently improves accuracy-efficiency trade-offs under comparable computational budgets, achieving 93.15% accuracy on CIFAR-10 and up to 11.7x faster inference than spline-based KAN variants. Code and trained models will be released.
[784] On the Infinite Width and Depth Limits of Predictive Coding Networks
Francesco Innocenti, El Mehdi Achour, Rafal Bogacz
Main category: cs.LG
TL;DR: Predictive coding networks can achieve the same gradient computations as backpropagation when properly parameterized and scaled to infinite width/depth limits, unifying biological plausibility with deep learning efficiency.
Details
Motivation: Predictive coding (PC) offers a biologically plausible alternative to backpropagation (BP), but its scalability and theoretical foundations remain unclear. The paper aims to establish theoretical connections between PC and BP in deep networks.Method: Theoretical analysis of infinite width and depth limits of PC networks, focusing on linear residual networks. Study of width- and depth-stable feature-learning parameterizations, showing equivalence between PC and BP parameterizations. Analysis of PC energy convergence to BP loss in wide-shallow regimes.
Result: For linear residual networks, PC and BP have identical width- and depth-stable parameterizations. PC energy with equilibrated activities converges to BP loss when width » depth, resulting in identical gradient computations. Experiments confirm these results hold for deep nonlinear networks when activity equilibrium is reached.
Conclusion: PC networks can compute the same gradients as BP when properly parameterized and scaled, unifying biological plausibility with deep learning efficiency. This has important implications for scaling PC networks and provides theoretical grounding for previous empirical results.
Abstract: Predictive coding (PC) is a biologically plausible alternative to standard backpropagation (BP) that minimises an energy function with respect to network activities before updating weights. Recent work has improved the training stability of deep PC networks (PCNs) by leveraging some BP-inspired reparameterisations. However, the full scalability and theoretical basis of these approaches remains unclear. To address this, we study the infinite width and depth limits of PCNs. For linear residual networks, we show that the set of width- and depth-stable feature-learning parameterisations for PC is exactly the same as for BP. Moreover, under any of these parameterisations, the PC energy with equilibrated activities converges to the BP loss in a regime where the model width is much larger than the depth, resulting in PC computing the same gradients as BP. Experiments show that these results hold in practice for deep nonlinear networks, as long as an activity equilibrium seem to be reached. Overall, this work unifies various previous theoretical and empirical results and has potentially important implications for the scaling of PCNs.
[785] Dense Feature Learning via Linear Structure Preservation in Medical Data
Yuanyun Zhang, Mingxuan Zhang, Siyuan Li, Zihan Wang, Haoran Chen, Wenbo Zhou, Shi Li
Main category: cs.LG
TL;DR: Dense feature learning framework for medical AI that shapes embedding geometry through spectral balance, subspace consistency, and feature orthogonality objectives, improving representation quality without labels or reconstruction.
Details
Motivation: Current medical AI models use task-specific objectives that collapse representations onto few discriminative directions, underutilizing clinical data structure and limiting transferability, stability, and interpretability of learned features.Method: Proposes dense feature learning - a representation-centric framework operating directly on embedding matrices. Uses objectives defined by linear algebraic properties to encourage spectral balance, subspace consistency, and feature orthogonality, without relying on labels or generative reconstruction.
Result: Produces representations with higher effective rank, improved conditioning, greater stability across time. Empirical evaluations across longitudinal EHR data, clinical text, and multimodal patient representations show consistent improvements in downstream linear performance, robustness, and subspace alignment compared to supervised and self-supervised baselines.
Conclusion: Learning to span clinical variation may be as important as learning to predict clinical outcomes. Representation geometry should be a first-class objective in medical AI, with dense feature learning offering a promising approach.
Abstract: Deep learning models for medical data are typically trained using task specific objectives that encourage representations to collapse onto a small number of discriminative directions. While effective for individual prediction problems, this paradigm underutilizes the rich structure of clinical data and limits the transferability, stability, and interpretability of learned features. In this work, we propose dense feature learning, a representation centric framework that explicitly shapes the linear structure of medical embeddings. Our approach operates directly on embedding matrices, encouraging spectral balance, subspace consistency, and feature orthogonality through objectives defined entirely in terms of linear algebraic properties. Without relying on labels or generative reconstruction, dense feature learning produces representations with higher effective rank, improved conditioning, and greater stability across time. Empirical evaluations across longitudinal EHR data, clinical text, and multimodal patient representations demonstrate consistent improvements in downstream linear performance, robustness, and subspace alignment compared to supervised and self supervised baselines. These results suggest that learning to span clinical variation may be as important as learning to predict clinical outcomes, and position representation geometry as a first class objective in medical AI.
[786] Quantifying Explanation Quality in Graph Neural Networks using Out-of-Distribution Generalization
Ding Zhang, Siddharth Betala, Chirag Agarwal
Main category: cs.LG
TL;DR: EGS is a new metric for evaluating GNN explanations based on causal relevance and OOD generalization, showing better correlation with true causal variables than traditional fidelity metrics.
Details
Motivation: Current evaluation metrics for GNN explanations (like fidelity and sparsity) often fail to assess whether explanations identify true underlying causal variables, creating a need for more principled evaluation methods.Method: Proposes Explanation-Generalization Score (EGS) based on feature invariance principle, using a framework that trains GNNs with explanatory subgraphs and evaluates their OOD generalization performance as a proxy for causal validity.
Result: Large-scale validation with 11,200 model combinations across synthetic and real-world datasets shows EGS provides principled benchmarking for ranking explainers based on ability to capture causal substructures.
Conclusion: EGS offers a robust alternative to traditional fidelity-based metrics by quantifying causal relevance of GNN explanations through OOD generalization performance.
Abstract: Evaluating the quality of post-hoc explanations for Graph Neural Networks (GNNs) remains a significant challenge. While recent years have seen an increasing development of explainability methods, current evaluation metrics (e.g., fidelity, sparsity) often fail to assess whether an explanation identifies the true underlying causal variables. To address this, we propose the Explanation-Generalization Score (EGS), a metric that quantifies the causal relevance of GNN explanations. EGS is founded on the principle of feature invariance and posits that if an explanation captures true causal drivers, it should lead to stable predictions across distribution shifts. To quantify this, we introduce a framework that trains GNNs using explanatory subgraphs and evaluates their performance in Out-of-Distribution (OOD) settings (here, OOD generalization serves as a rigorous proxy for the explanation’s causal validity). Through large-scale validation involving 11,200 model combinations across synthetic and real-world datasets, our results demonstrate that EGS provides a principled benchmark for ranking explainers based on their ability to capture causal substructures, offering a robust alternative to traditional fidelity-based metrics.
[787] Towards Robust Scaling Laws for Optimizers
Alexandra Volkova, Mher Safaryan, Christoph H. Lampert, Dan Alistarh
Main category: cs.LG
TL;DR: This paper studies scaling laws for different optimizers in LLM pretraining, showing that separate Chinchilla-style scaling laws per optimizer are ill-conditioned, proposing a unified law with shared exponents and optimizer-specific scaling factors, and providing theoretical analysis for convex quadratic objectives.
Details
Motivation: Existing scaling law studies typically fix the optimizer (usually AdamW), while new optimizers promise better convergence but their relationship with model/data scaling is not well understood. The paper aims to understand how different optimizers affect scaling laws in LLM pretraining.Method: 1) Empirical study showing separate Chinchilla-style scaling laws per optimizer are ill-conditioned with highly correlated parameters. 2) Proposes a more robust unified scaling law with shared power-law exponents across optimizers and optimizer-specific rescaling factors. 3) Provides theoretical analysis for gradient-based methods on convex quadratic objectives, showing scaling laws emerge from loss decomposition into irreducible, approximation, and optimization errors.
Result: The paper demonstrates that a unified scaling law with shared exponents and optimizer-specific factors enables direct comparison between optimizers and provides theoretical grounding for how scaling laws emerge from fundamental loss components.
Conclusion: Optimizer choice affects scaling laws in LLM pretraining, and a unified framework with shared exponents and optimizer-specific scaling factors provides a more robust way to compare different optimization algorithms and understand their scaling behavior.
Abstract: The quality of Large Language Model (LLM) pretraining depends on multiple factors, including the compute budget and the choice of optimization algorithm. Empirical scaling laws are widely used to predict loss as model size and training data grow, however, almost all existing studies fix the optimizer (typically AdamW). At the same time, a new generation of optimizers (e.g., Muon, Shampoo, SOAP) promises faster and more stable convergence, but their relationship with model and data scaling is not yet well understood. In this work, we study scaling laws across different optimizers. Empirically, we show that 1) separate Chinchilla-style scaling laws for each optimizer are ill-conditioned and have highly correlated parameters. Instead, 2) we propose a more robust law with shared power-law exponents and optimizer-specific rescaling factors, which enable direct comparison between optimizers. Finally, 3) we provide a theoretical analysis of gradient-based methods for the proxy task of a convex quadratic objective, demonstrating that Chinchilla-style scaling laws emerge naturally as a result of loss decomposition into irreducible, approximation, and optimization errors.
[788] Analyzing and Guiding Zero-Shot Posterior Sampling in Diffusion Models
Roi Benita, Michael Elad, Joseph Keshet
Main category: cs.LG
TL;DR: A theoretical analysis of diffusion-based inverse problem solvers under Gaussian prior assumption, enabling closed-form spectral analysis and principled parameter design.
Details
Motivation: Current diffusion-based methods for inverse problems rely on manual tuning and heuristics. The authors aim to provide rigorous theoretical analysis to replace these heuristic approaches with principled parameter design.Method: Assume Gaussian prior distribution, derive closed-form expressions for ideal posterior sampler and diffusion-based reconstruction algorithms in spectral domain, enabling analytical comparisons and principled parameter design framework.
Result: Developed method-agnostic framework for parameter design that accounts for prior characteristics, degraded signal properties, and diffusion dynamics. Showed spectral recommendations differ from standard heuristics and vary with diffusion step size.
Conclusion: Theoretical analysis enables principled parameter selection for diffusion-based inverse problem solvers, providing consistent balance between perceptual quality and signal fidelity, replacing heuristic approaches.
Abstract: Recovering a signal from its degraded measurements is a long standing challenge in science and engineering. Recently, zero-shot diffusion based methods have been proposed for such inverse problems, offering a posterior sampling based solution that leverages prior knowledge. Such algorithms incorporate the observations through inference, often leaning on manual tuning and heuristics. In this work we propose a rigorous analysis of such approximate posterior-samplers, relying on a Gaussianity assumption of the prior. Under this regime, we show that both the ideal posterior sampler and diffusion-based reconstruction algorithms can be expressed in closed-form, enabling their thorough analysis and comparisons in the spectral domain. Building on these representations, we also introduce a principled framework for parameter design, replacing heuristic selection strategies used to date. The proposed approach is method-agnostic and yields tailored parameter choices for each algorithm, jointly accounting for the characteristics of the prior, the degraded signal, and the diffusion dynamics. We show that our spectral recommendations differ structurally from standard heuristics and vary with the diffusion step size, resulting in a consistent balance between perceptual quality and signal fidelity.
[789] Efficient Planning in Reinforcement Learning via Model Introspection
Gabriel Stella
Main category: cs.LG
TL;DR: The paper proposes using program analysis as introspection to bridge reinforcement learning and classical planning, enabling efficient goal-oriented planning over relational RL models.
Details
Motivation: Humans can solve tasks regardless of specification by introspecting their internal models, but RL and classical planning remain distinct with different formulations. The paper aims to bridge this gap by viewing introspection as program analysis.Method: Proposes program analysis as a form of introspection to synthesize task-relevant information from internal models. Describes an algorithm for efficient goal-oriented planning over relational reinforcement learning models.
Result: Demonstrates a novel link between reinforcement learning and classical planning through program analysis, enabling more efficient planning over relational RL models.
Conclusion: Program analysis can serve as introspection to bridge RL and classical planning, allowing agents to derive additional task information from their internal models for more efficient problem-solving.
Abstract: Reinforcement learning and classical planning are typically seen as two distinct problems, with differing formulations necessitating different solutions. Yet, when humans are given a task, regardless of the way it is specified, they can often derive the additional information needed to solve the problem efficiently. The key to this ability is introspection: by reasoning about their internal models of the problem, humans directly synthesize additional task-relevant information. In this paper, we propose that this introspection can be thought of as program analysis. We discuss examples of how this approach can be applied to various kinds of models used in reinforcement learning. We then describe an algorithm that enables efficient goal-oriented planning over the class of models used in relational reinforcement learning, demonstrating a novel link between reinforcement learning and classical planning.
[790] ParisKV: Fast and Drift-Robust KV-Cache Retrieval for Long-Context LLMs
Yanlin Qi, Xinhang Chen, Huiqiang Jiang, Qitong Wang, Botao Peng, Themis Palpanas
Main category: cs.LG
TL;DR: ParisKV is a GPU-native KV-cache retrieval framework for long-context LLM inference that addresses distribution drift and latency issues through collision-based candidate selection and quantized inner-product reranking, enabling efficient million-token context processing.
Details
Motivation: Existing KV-cache retrieval methods for long-context LLM inference struggle with distribution drift and high latency at scale, particularly when dealing with million-token contexts where full attention becomes memory-prohibitive.Method: ParisKV uses collision-based candidate selection followed by quantized inner-product reranking estimator. It supports CPU-offloaded KV caches via Unified Virtual Addressing (UVA) for on-demand top-k fetching with minimal overhead, enabling efficient processing of million-token contexts.
Result: ParisKV matches or outperforms full attention quality on long-input and long-generation benchmarks. It achieves state-of-the-art decoding efficiency: matches or exceeds full attention speed even at batch size 1 for long contexts, delivers up to 2.8× higher throughput, and scales to million-token contexts where full attention fails. At million-token scale, it reduces decode latency by 17× and 44× compared to MagicPIG and PQCache respectively.
Conclusion: ParisKV provides a drift-robust, GPU-native KV-cache retrieval framework that enables efficient long-context LLM inference at million-token scale while maintaining or improving quality compared to full attention.
Abstract: KV-cache retrieval is essential for long-context LLM inference, yet existing methods struggle with distribution drift and high latency at scale. We introduce ParisKV, a drift-robust, GPU-native KV-cache retrieval framework based on collision-based candidate selection, followed by a quantized inner-product reranking estimator. For million-token contexts, ParisKV supports CPU-offloaded KV caches via Unified Virtual Addressing (UVA), enabling on-demand top-$k$ fetching with minimal overhead. ParisKV matches or outperforms full attention quality on long-input and long-generation benchmarks. It achieves state-of-the-art long-context decoding efficiency: it matches or exceeds full attention speed even at batch size 1 for long contexts, delivers up to 2.8$\times$ higher throughput within full attention’s runnable range, and scales to million-token contexts where full attention runs out of memory. At million-token scale, ParisKV reduces decode latency by 17$\times$ and 44$\times$ compared to MagicPIG and PQCache, respectively, two state-of-the-art KV-cache Top-$k$ retrieval baselines.
[791] Do We Need Adam? Surprisingly Strong and Sparse Reinforcement Learning with SGD in LLMs
Sagnik Mukherjee, Lifan Yuan, Pavan Jayasinha, Dilek Hakkani-Tür, Hao Peng
Main category: cs.LG
TL;DR: SGD optimizer matches or outperforms AdamW for RL in LLMs with extreme parameter sparsity (0.02% updates), offering memory efficiency and new insights into RL optimization dynamics.
Details
Motivation: Current RL practices for LLMs follow optimization methods from pretraining/SFT stages, using AdamW despite its high memory overhead. The paper investigates whether RL benefits less from Adam-style adaptive learning rates and momentum compared to supervised learning.Method: Analyzed the influence of momentum and adaptive learning rates in AdamW for RL vs SFT, then experimentally compared SGD (which is memory-efficient) against AdamW for RL in LLMs. Examined parameter update patterns and sparsity.
Result: SGD matches or outperforms AdamW in RL for LLMs while updating fewer than 0.02% of model parameters (1000x fewer than AdamW) without any sparsity regularization. RL shows different optimization dynamics than supervised learning.
Conclusion: RL for LLMs benefits less from adaptive learning rates and momentum than supervised learning, enabling highly parameter-efficient optimization with SGD. This provides new insights into RL optimization dynamics and shows RL can be substantially more parameter-efficient than previously recognized.
Abstract: Reinforcement learning (RL), particularly RL from verifiable reward (RLVR), has become a crucial phase of training large language models (LLMs) and a key focus of current scaling efforts. However, optimization practices in RL largely follow those of next-token prediction stages (e.g., pretraining and supervised fine-tuning), despite fundamental differences between RL and these stages highlighted by recent work. One such practice is the use of the AdamW optimizer, which is widely adopted for training large-scale transformers despite its high memory overhead. Our analysis shows that both momentum and adaptive learning rates in AdamW are less influential in RL than in SFT, leading us to hypothesize that RL benefits less from Adam-style per-parameter adaptive learning rates and momentum. Confirming this hypothesis, our experiments demonstrate that the substantially more memory-efficient SGD, which is known to perform poorly in supervised learning of large-scale transformers, matches or even outperforms AdamW in RL for LLMs. Remarkably, full fine-tuning with SGD updates fewer than 0.02% of model parameters without any sparsity-promoting regularization, more than 1000 times fewer than AdamW. Our analysis offers potential reasons for this update sparsity. These findings provide new insights into the optimization dynamics of RL in LLMs and show that RL can be substantially more parameter-efficient than previously recognized.
[792] The Laplacian Keyboard: Beyond the Linear Span
Siddarth Chandrasekar, Marlos C. Machado
Main category: cs.LG
TL;DR: Laplacian Keyboard (LK) uses Laplacian eigenvectors to create a hierarchical framework for RL, constructing a task-agnostic library of options that can approximate optimal policies for any reward in the linear span, with a meta-policy that stitches options dynamically.
Details
Motivation: Laplacian eigenvectors provide a natural basis for approximating reward functions in RL, but their use is typically limited to linear span, restricting expressivity in complex environments. The authors aim to go beyond this limitation while leveraging the fundamental properties of Laplacian eigenvectors.Method: LK constructs a hierarchical framework that builds a task-agnostic library of options from Laplacian eigenvectors, forming a behavior basis guaranteed to contain the optimal policy for any reward within the linear span. A meta-policy learns to dynamically stitch these options together.
Result: Theoretical bounds on zero-shot approximation error are established. Empirically, LK surpasses zero-shot solutions while achieving improved sample efficiency compared to standard RL methods.
Conclusion: LK provides a hierarchical framework that extends beyond linear constraints of Laplacian eigenvectors, enabling efficient learning of policies outside original linear constraints while maintaining theoretical guarantees and practical efficiency.
Abstract: Across scientific disciplines, Laplacian eigenvectors serve as a fundamental basis for simplifying complex systems, from signal processing to quantum mechanics. In reinforcement learning (RL), these eigenvectors provide a natural basis for approximating reward functions; however, their use is typically limited to their linear span, which restricts expressivity in complex environments. We introduce the Laplacian Keyboard (LK), a hierarchical framework that goes beyond the linear span. LK constructs a task-agnostic library of options from these eigenvectors, forming a behavior basis guaranteed to contain the optimal policy for any reward within the linear span. A meta-policy learns to stitch these options dynamically, enabling efficient learning of policies outside the original linear constraints. We establish theoretical bounds on zero-shot approximation error and demonstrate empirically that LK surpasses zero-shot solutions while achieving improved sample efficiency compared to standard RL methods.
[793] Efficient Adaptive Data Analysis over Dense Distributions
Joon Suk Huh
Main category: cs.LG
TL;DR: A computationally efficient adaptive data analysis mechanism achieves optimal O(log T) sample complexity for dense data distributions, connecting adaptive analysis with privacy beyond differential privacy.
Details
Motivation: Adaptive data analysis workflows repeatedly query datasets, causing overfitting and invalid inference. There's a fundamental tension between computational efficiency and sample complexity - efficient algorithms have suboptimal O(√T) complexity while optimal O(log T) algorithms are computationally intractable.Method: Proposes a computationally efficient ADA mechanism that attains optimal O(log T) sample complexity when data distributions are dense with respect to a known prior. This includes feature-label distributions in distribution-specific learning, and yields a sample-efficient statistical query oracle.
Result: The mechanism achieves optimal sample complexity while being computationally efficient for dense distributions. Although not based on differential privacy, it satisfies Predicate Singling Out (PSO) security, revealing connections between adaptive data analysis and privacy beyond differential privacy.
Conclusion: Identifies a natural class of data distributions where both computational efficiency and optimal sample complexity are achievable, bridging adaptive data analysis with privacy concepts beyond differential privacy through PSO security.
Abstract: Modern data workflows are inherently adaptive, repeatedly querying the same dataset to refine and validate sequential decisions, but such adaptivity can lead to overfitting and invalid statistical inference. Adaptive Data Analysis (ADA) mechanisms address this challenge; however, there is a fundamental tension between computational efficiency and sample complexity. For $T$ rounds of adaptive analysis, computationally efficient algorithms typically incur suboptimal $O(\sqrt{T})$ sample complexity, whereas statistically optimal $O(\log T)$ algorithms are computationally intractable under standard cryptographic assumptions. In this work, we shed light on this trade-off by identifying a natural class of data distributions under which both computational efficiency and optimal sample complexity are achievable. We propose a computationally efficient ADA mechanism that attains optimal $O(\log T)$ sample complexity when the data distribution is dense with respect to a known prior. This setting includes, in particular, feature–label data distributions arising in distribution-specific learning. As a consequence, our mechanism also yields a sample-efficient (i.e., $O(\log T)$ samples) statistical query oracle in the distribution-specific setting. Moreover, although our algorithm is not based on differential privacy, it satisfies a relaxed privacy notion known as Predicate Singling Out (PSO) security (Cohen and Nissim, 2020). Our results thus reveal an inherent connection between adaptive data analysis and privacy beyond differential privacy.
[794] TerraBind: Fast and Accurate Binding Affinity Prediction through Coarse Structural Representations
Matteo Rossi, Ryan Pederson, Miles Wang-Henderson, Ben Kaufman, Edward C. Williams, Carl Underkoffler, Owen Lewis Howell, Adrian Layer, Stephan Thaler, Narbe Mardirossian, John Anthony Parkhill
Main category: cs.LG
TL;DR: TerraBind is a fast protein-ligand structure and binding affinity prediction model using coarse pocket-level representation and multimodal architecture, achieving 26x faster inference and 20% better affinity prediction than SOTA methods.
Details
Motivation: Current deep learning approaches for structure-based drug design rely on expensive all-atom diffusion, creating inference bottlenecks that make large-scale compound screening computationally intractable. The authors hypothesize that full all-atom resolution is unnecessary for accurate small molecule pose and binding affinity prediction.Method: Uses coarse pocket-level representation (protein Cβ atoms and ligand heavy atoms only) with multimodal architecture combining COATI-3 molecular encodings and ESM-2 protein embeddings. Includes diffusion-free optimization for pose generation and binding affinity likelihood prediction module.
Result: Achieves 26-fold faster inference than SOTA methods while improving affinity prediction accuracy by ~20%. Matches diffusion-based baselines in ligand pose accuracy on structure prediction benchmarks. Outperforms Boltz-2 by ~20% in Pearson correlation for binding affinity prediction on both public and proprietary datasets.
Conclusion: TerraBind demonstrates that coarse pocket-level representation is sufficient for accurate protein-ligand structure and binding prediction, enabling efficient large-scale compound screening with well-calibrated uncertainty estimates and continual learning capabilities.
Abstract: We present TerraBind, a foundation model for protein-ligand structure and binding affinity prediction that achieves 26-fold faster inference than state-of-the-art methods while improving affinity prediction accuracy by $\sim$20%. Current deep learning approaches to structure-based drug design rely on expensive all-atom diffusion to generate 3D coordinates, creating inference bottlenecks that render large-scale compound screening computationally intractable. We challenge this paradigm with a critical hypothesis: full all-atom resolution is unnecessary for accurate small molecule pose and binding affinity prediction. TerraBind tests this hypothesis through a coarse pocket-level representation (protein C$_β$ atoms and ligand heavy atoms only) within a multimodal architecture combining COATI-3 molecular encodings and ESM-2 protein embeddings that learns rich structural representations, which are used in a diffusion-free optimization module for pose generation and a binding affinity likelihood prediction module. On structure prediction benchmarks (FoldBench, PoseBusters, Runs N’ Poses), TerraBind matches diffusion-based baselines in ligand pose accuracy. Crucially, TerraBind outperforms Boltz-2 by $\sim$20% in Pearson correlation for binding affinity prediction on both a public benchmark (CASP16) and a diverse proprietary dataset (18 biochemical/cell assays). We show that the affinity prediction module also provides well-calibrated affinity uncertainty estimates, addressing a critical gap in reliable compound prioritization for drug discovery. Furthermore, this module enables a continual learning framework and a hedged batch selection strategy that, in simulated drug discovery cycles, achieves 6$\times$ greater affinity improvement of selected molecules over greedy-based approaches.
[795] Learnable Chernoff Baselines for Inference-Time Alignment
Sunil Madhow, Yuchen Liang, Ness Shroff, Yingbin Liang, Yu-Xiang Wang
Main category: cs.LG
TL;DR: Learnable Chernoff Baselines (LCBs) enable efficient inference-time reward-guided alignment for generative models using adaptive rejection sampling with theoretical guarantees.
Details
Motivation: Existing methods for inference-time reward-guided alignment often require architecture-specific adaptations or are computationally expensive, creating a need for efficient black-box approaches.Method: LCBs use learnable baselines to implement adaptive rejection sampling from exponentially tilted kernels, requiring only black-box sampling access to pretrained models while controlling inference-compute scaling.
Result: LCBs achieve close approximation to ideal rejection sampling with significantly fewer queries to pretrained models, demonstrated in both continuous and discrete diffusion settings with total-variation guarantees.
Conclusion: LCBs provide an efficient, flexible method for inference-time reward alignment that works with black-box models and offers theoretical guarantees while reducing computational costs.
Abstract: We study inference-time reward-guided alignment for generative models. Existing methods often rely on either architecture-specific adaptations or computationally costly inference procedures. We introduce Learnable Chernoff Baselines (LCBs) as a method for efficiently and approximately sampling from the exponentially tilted kernels that arise from KL-regularized reward alignment. Using only black-box sampling access to the pretrained model, LCBs implement a form of rejection sampling with adaptively selected acceptance probabilities, which allows fine-grained control over inference-compute scaling. We establish total-variation guarantees to the ideal aligned model, and demonstrate in both continuous and discrete diffusion settings that LCB sampling closely matches ideal rejection sampling while using substantially fewer queries to the pretrained model.
[796] Riemannian MeanFlow
Dongyeop Woo, Marta Skreta, Seonghyun Park, Sungsoo Ahn, Kirill Neklyudov
Main category: cs.LG
TL;DR: Riemannian MeanFlow (RMF) enables efficient generative modeling on manifolds with single-forward-pass generation, achieving comparable quality to diffusion models while requiring 10x fewer function evaluations.
Details
Motivation: Current diffusion and flow models on Riemannian manifolds require many neural network evaluations at inference time, creating computational bottlenecks for large-scale scientific sampling workflows like protein backbone generation and DNA sequence design.Method: Introduces Riemannian MeanFlow (RMF) framework for learning flow maps directly on manifolds. Derives three equivalent characterizations of manifold average velocity (Eulerian, Lagrangian, and semigroup identities), and develops parameterizations and stabilization techniques for high-dimensional manifolds.
Result: In promoter DNA design and protein backbone generation, RMF achieves comparable sample quality to prior methods while requiring up to 10x fewer function evaluations. Also enables efficient reward-guided design through reward look-ahead.
Conclusion: RMF provides an efficient alternative to diffusion models for generative modeling on manifolds, enabling high-quality generation with minimal computational cost, which is valuable for large-scale scientific applications.
Abstract: Diffusion and flow models have become the dominant paradigm for generative modeling on Riemannian manifolds, with successful applications in protein backbone generation and DNA sequence design. However, these methods require tens to hundreds of neural network evaluations at inference time, which can become a computational bottleneck in large-scale scientific sampling workflows. We introduce Riemannian MeanFlow~(RMF), a framework for learning flow maps directly on manifolds, enabling high-quality generations with as few as one forward pass. We derive three equivalent characterizations of the manifold average velocity (Eulerian, Lagrangian, and semigroup identities), and analyze parameterizations and stabilization techniques to improve training on high-dimensional manifolds. In promoter DNA design and protein backbone generation settings, RMF achieves comparable sample quality to prior methods while requiring up to 10$\times$ fewer function evaluations. Finally, we show that few-step flow maps enable efficient reward-guided design through reward look-ahead, where terminal states can be predicted from intermediate steps at minimal additional cost.
[797] Preference Conditioned Multi-Objective Reinforcement Learning: Decomposed, Diversity-Driven Policy Optimization
Tanmay Ambadkar, Sourav Panda, Shreyash Kale, Jonathan Dodge, Abhinav Verma
Main category: cs.LG
TL;DR: D³PO is a PPO-based multi-objective RL framework that addresses gradient interference and representational collapse in preference-conditioned policies through decomposed optimization and diversity regularization.
Details
Motivation: Current multi-objective RL methods using single preference-conditioned policies often fail to recover complete Pareto fronts due to destructive gradient interference from premature scalarization and representational collapse across preference space.Method: D³PO reorganizes multi-objective policy optimization with: 1) decomposed optimization pipeline preserving per-objective learning signals, integrating preferences only after stabilization; 2) scaled diversity regularizer enforcing policy sensitivity to preference changes to prevent collapse.
Result: Across standard MORL benchmarks including high-dimensional and many-objective control tasks, D³PO consistently discovers broader and higher-quality Pareto fronts than prior single- and multi-policy methods, matching or exceeding state-of-the-art hypervolume and expected utility.
Conclusion: D³PO successfully addresses structural issues in MORL, enabling reliable single preference-conditioned policies that can recover complete Pareto fronts, making it a practical and scalable solution for multi-objective decision making.
Abstract: Multi-objective reinforcement learning (MORL) seeks to learn policies that balance multiple, often conflicting objectives. Although a single preference-conditioned policy is the most flexible and scalable solution, existing approaches remain brittle in practice, frequently failing to recover complete Pareto fronts. We show that this failure stems from two structural issues in current methods: destructive gradient interference caused by premature scalarization and representational collapse across the preference space. We introduce $D^3PO$, a PPO-based framework that reorganizes multi-objective policy optimization to address these issues directly. $D^3PO$ preserves per-objective learning signals through a decomposed optimization pipeline and integrates preferences only after stabilization, enabling reliable credit assignment. In addition, a scaled diversity regularizer enforces sensitivity of policy behavior to preference changes, preventing collapse. Across standard MORL benchmarks, including high-dimensional and many-objective control tasks, $D^3PO$ consistently discovers broader and higher-quality Pareto fronts than prior single- and multi-policy methods, matching or exceeding state-of-the-art hypervolume and expected utility while using a single deployable policy.
[798] MaD-Mix: Multi-Modal Data Mixtures via Latent Space Coupling for Vision-Language Model Training
Wanyun Xie, Francesco Tonin, Volkan Cevher
Main category: cs.LG
TL;DR: MaD-Mix is a framework for automatically deriving optimal multi-modal data mixtures for Vision-Language Model training using modality-aware domain alignment maximization, eliminating costly manual tuning.
Details
Motivation: Current VLM training relies on expensive manual tuning of data mixtures across diverse multi-modal domains. There's a need for a principled, computationally efficient method to automatically determine optimal data mixtures, especially for complex scenarios like tri-modal video-image-text settings where manual tuning becomes impractical.Method: MaD-Mix formulates data mixing as modality-aware domain alignment maximization. It obtains closed-form multi-modal alignment scores from the Fenchel dual through inter-modal coupling variables. The framework systematically handles domains with missing modalities, allowing integration of language-only domains.
Result: Empirical evaluations across 0.5B and 7B models show MaD-Mix accelerates VLM training across diverse benchmarks. It matches human-tuned data mixtures using 22% fewer training steps in image-text instruction tuning. In tri-modal video-image-text scenarios, it boosts average accuracy over uniform weights with negligible computation overhead (<1 GPU-hour).
Conclusion: MaD-Mix provides a scalable, efficient framework for automatic data mixture design in VLM training pipelines, eliminating the need for costly manual tuning while improving performance and training efficiency.
Abstract: Vision-Language Models (VLMs) are typically trained on a diverse set of multi-modal domains, yet current practices rely on costly manual tuning. We propose MaD-Mix, a principled and computationally efficient framework that derives multi-modal data mixtures for VLM training. MaD-Mix formulates data mixing as modality-aware domain alignment maximization and obtains closed-form multi-modal alignment scores from the Fenchel dual through inter-modal coupling variables. MaD-Mix systematically handles domains with missing modalities, allowing for the integration of language-only domains. Empirical evaluations across 0.5B and 7B models demonstrate that MaD-Mix accelerates VLM training across diverse benchmarks. MaD-Mix matches human-tuned data mixtures using 22% fewer training steps in image-text instruction tuning. In complex tri-modal video-image-text scenarios, where manual tuning becomes impractical, MaD-Mix boosts average accuracy over uniform weights, with negligible mixture computation overhead (< 1 GPU-hour), enabling scalable mixture design for modern VLM pipelines.
[799] CausalTAD: Injecting Causal Knowledge into Large Language Models for Tabular Anomaly Detection
Ruiqi Wang, Ruikang Liu, Runyu Chen, Haoxiang Suo, Zhiyi Peng, Zhuo Tang, Changjian Chen
Main category: cs.LG
TL;DR: CausalTaD improves tabular anomaly detection by injecting causal knowledge into LLMs through column reordering based on causal relationships and column reweighting.
Details
Motivation: Current LLM-based tabular anomaly detection methods randomly order columns during text conversion, ignoring crucial causal relationships between columns that are essential for accurate anomaly detection.Method: 1) Identify causal relationships between columns and reorder them to align with these relationships (modeled as linear ordering problem), 2) Propose reweighting strategy to assign different weights to columns based on their contribution to causal relationships.
Result: Experiments across more than 30 datasets demonstrate consistent outperformance over current state-of-the-art methods.
Conclusion: Injecting causal knowledge into LLMs through column reordering and reweighting significantly improves tabular anomaly detection performance.
Abstract: Detecting anomalies in tabular data is critical for many real-world applications, such as credit card fraud detection. With the rapid advancements in large language models (LLMs), state-of-the-art performance in tabular anomaly detection has been achieved by converting tabular data into text and fine-tuning LLMs. However, these methods randomly order columns during conversion, without considering the causal relationships between them, which is crucial for accurately detecting anomalies. In this paper, we present CausalTaD, a method that injects causal knowledge into LLMs for tabular anomaly detection. We first identify the causal relationships between columns and reorder them to align with these causal relationships. This reordering can be modeled as a linear ordering problem. Since each column contributes differently to the causal relationships, we further propose a reweighting strategy to assign different weights to different columns to enhance this effect. Experiments across more than 30 datasets demonstrate that our method consistently outperforms the current state-of-the-art methods. The code for CausalTAD is available at https://github.com/350234/CausalTAD.
[800] Fairness Aware Reward Optimization
Ching Lam Choi, Vighnesh Subramaniam, Phillip Isola, Antonio Torralba, Stefanie Jegelka
Main category: cs.LG
TL;DR: Faro is a fairness-aware reward optimization framework that trains reward models under demographic fairness constraints to reduce bias propagation in LLM alignment.
Details
Motivation: Demographic biases in human preference data propagate through reward models into aligned LLMs, creating systematic unfairness that needs to be addressed during the alignment process.Method: Faro trains reward models under fairness constraints (demographic parity, equalized odds, or counterfactual fairness) while maintaining ordinal ranking correctness and cardinal calibration, with theoretical analysis of fairness certificates and accuracy-fairness trade-offs.
Result: Faro significantly reduces bias and harmful generations across multiple LLMs and benchmarks while maintaining or improving model quality, with provable fairness guarantees.
Conclusion: Faro provides an effective in-processing framework for fair LLM alignment that ensures reward models are simultaneously ordinal, cardinal, and fair, addressing bias propagation at the reward modeling stage.
Abstract: Demographic skews in human preference data propagate systematic unfairness through reward models into aligned LLMs. We introduce Fairness Aware Reward Optimization (Faro), an in-processing framework that trains reward models under demographic parity, equalized odds, or counterfactual fairness constraints. We provide the first theoretical analysis of reward-level fairness in LLM alignment, establishing: (i) provable fairness certificates for Faro-trained rewards with controllable slack; a (ii) formal characterization of the accuracy-fairness trade-off induced by KL-regularized fine-tuning, proving fairness transfers from reward to policy; and the (iii) existence of a non-empty Pareto frontier. Unlike pre- and post-processing methods, Faro ensures reward models are simultaneously ordinal (ranking correctly), cardinal (calibrated), and fair. Across multiple LLMs and benchmarks, Faro significantly reduces bias and harmful generations while maintaining or improving model quality.
[801] Approximating Matrix Functions with Deep Neural Networks and Transformers
Rahul Padmanabhan, Simone Brugiapaglia
Main category: cs.LG
TL;DR: Transformers can approximate matrix functions like matrix exponential with proper numerical encodings, achieving 5% relative error.
Details
Motivation: While transformers excel in NLP, their application to numerical computation and matrix functions (like matrix exponential in scientific computing) remains underexplored.Method: Two approaches: 1) Theoretical analysis of ReLU network depth/width bounds for matrix exponential approximation; 2) Experimental transformer encoder-decoder with various numerical encoding schemes.
Result: Proved theoretical bounds for ReLU networks; transformers achieved 5% relative error on matrix functions with appropriate encodings, where encoding choice significantly impacts performance.
Conclusion: Transformers can effectively approximate matrix functions, with encoding scheme being crucial for performance, opening new directions for neural networks in scientific computing.
Abstract: Transformers have revolutionized natural language processing, but their use for numerical computation has received less attention. We study the approximation of matrix functions, which map scalar functions to matrices, using neural networks including transformers. We focus on functions mapping square matrices to square matrices of the same dimension. These types of matrix functions appear throughout scientific computing, e.g., the matrix exponential in continuous-time Markov chains and the matrix sign function in stability analysis of dynamical systems. In this paper, we make two contributions. First, we prove bounds on the width and depth of ReLU networks needed to approximate the matrix exponential to an arbitrary precision. Second, we show experimentally that a transformer encoder-decoder with suitable numerical encodings can approximate certain matrix functions at a relative error of 5% with high probability. Our study reveals that the encoding scheme strongly affects performance, with different schemes working better for different functions.
[802] Efficient Representations are Controllable Representations
Charles Ye, Jasmine Cui
Main category: cs.LG
TL;DR: Fine-tuning LLMs with auxiliary loss to create inert interpretability flags that become genuine internal features for controllable generation.
Details
Motivation: Current methods for controlling LLM representations require complex identification and intervention on existing feature geometry. The paper seeks a simpler brute-force approach to install interpretable, controllable features directly into model activations.Method: Fine-tune an LLM with a simple auxiliary loss that trains 16 of its 3072 residual stream dimensions to be inert interpretability flags. These flags indicate what concepts are required for generation, and the model reorganizes to rely on them during actual generation tasks.
Result: The inert flags become genuine internal features that serve as interpretable control switches, allowing steering of generation at inference time. The model eliminates redundant encodings elsewhere due to efficiency pressure, making these flags the primary representation.
Conclusion: Model efficiency pressure can be exploited as a lever to induce interpretable, controllable representations through simple auxiliary training of inert flags, bypassing complex feature identification and intervention methods.
Abstract: What is the most brute-force way to install interpretable, controllable features into a model’s activations? Controlling how LLMs internally represent concepts typically requires sophisticated methods to first identify, then intervene on the model’s existing feature geometry. We bypass all of this. We finetune an LLM with a simple auxiliary loss, training 16 of its 3072 residual stream dimensions to be inert interpretability flags that simply indicate what concepts are required for generation. The model reorganizes around them anyway, learning to rely on these flags during actual generation tasks. As a result, these inert flags become genuine internal features: interpretable control switches that allow us to steer generation at inference time. Why does this work? When a feature is reliably supplied at a fixed location, gradient descent gradually eliminates redundant encodings elsewhere, and the model erodes its own alternative representations. A model’s efficiency pressure is a lever - exploitable to induce interpretable, controllable representations.
[803] rePIRL: Learn PRM with Inverse RL for LLM Reasoning
Xian Wu, Kaijie Zhu, Ying Zhang, Lun Wang, Wenbo Guo
Main category: cs.LG
TL;DR: rePIRL is an inverse reinforcement learning framework for learning process reward models in LLM reasoning with minimal expert policy assumptions, using dual learning of policy and reward model.
Details
Motivation: Existing process reward model learning methods for LLM reasoning either rely on strong assumptions about expert policies (requiring their reward functions) or suffer from intrinsic limitations like entropy collapse, resulting in weak PRMs or limited generalizability.Method: Introduces rePIRL, an inverse RL-inspired framework with dual learning process that updates policy and PRM interchangeably. Includes customized techniques to address scaling traditional inverse RL to LLMs, and theoretically unifies online and offline PRM learning methods.
Result: Empirical evaluations on standardized math and coding reasoning datasets demonstrate effectiveness over existing methods. Shows application in test-time training, test-time scaling, and providing early signals for training hard problems. Ablation study validates training recipe and design choices.
Conclusion: rePIRL learns effective process reward models with minimal assumptions about expert policies, addressing limitations of existing methods and showing practical applications in LLM reasoning tasks.
Abstract: Process rewards have been widely used in deep reinforcement learning to improve training efficiency, reduce variance, and prevent reward hacking. In LLM reasoning, existing works also explore various solutions for learning effective process reward models (PRM) with or without the help of an expert policy. However, existing methods either rely on strong assumptions about the expert policies (e.g., requiring their reward functions) or suffer intrinsic limitations (e.g., entropy collapse), resulting in weak PRMs or limited generalizability. In this paper, we introduce rePIRL, an inverse RL-inspired framework that learns effective PRMs with minimal assumptions about expert policies. Specifically, we design a dual learning process that updates the policy and the PRM interchangeably. Our learning algorithm has customized techniques to address the challenges of scaling traditional inverse RL to LLMs. We theoretically show that our proposed learning framework can unify both online and offline PRM learning methods, justifying that rePIRL can learn PRMs with minimal assumptions. Empirical evaluations on standardized math and coding reasoning datasets demonstrate the effectiveness of rePIRL over existing methods. We further show the application of our trained PRM in test-time training, test-time scaling, and providing an early signal for training hard problems. Finally, we validate our training recipe and key design choices via a detailed ablation study.
[804] Interpretable Analytic Calabi-Yau Metrics via Symbolic Distillation
D Yang Eng
Main category: cs.LG
TL;DR: Symbolic regression distills neural approximations of Calabi-Yau manifold metrics into simple 5-term formulas with 3,000x fewer parameters while maintaining accuracy.
Details
Motivation: Calabi-Yau manifolds are crucial for string theory but their metrics are computationally intractable. Neural networks can approximate them but remain black-box models lacking interpretability.Method: Use symbolic regression to distill neural network approximations into simple, interpretable formulas. Multi-seed validation identifies essential geometric features like power sums and symmetric polynomials.
Result: Achieved R² = 0.9994 accuracy with 5-term formulas using 3,000-fold fewer parameters. Formulas maintain functional form across moduli range with smoothly varying coefficients. Successfully reproduces physical observables like volume integrals and Yukawa couplings.
Conclusion: Symbolic distillation can recover compact, interpretable models for complex geometric quantities previously accessible only through black-box neural networks, bridging computational physics and interpretable modeling.
Abstract: Calabi–Yau manifolds are essential for string theory but require computing intractable metrics. Here we show that symbolic regression can distill neural approximations into simple, interpretable formulas. Our five-term expression matches neural accuracy ($R^2 = 0.9994$) with 3,000-fold fewer parameters. Multi-seed validation confirms that geometric constraints select essential features, specifically power sums and symmetric polynomials, while permitting structural diversity. The functional form can be maintained across the studied moduli range ($ψ\in [0, 0.8]$) with coefficients varying smoothly; we interpret these trends as empirical hypotheses within the accuracy regime of the locally-trained teachers ($σ\approx 8-9%$ at $ψ\neq 0$). The formula reproduces physical observables – volume integrals and Yukawa couplings – validating that symbolic distillation recovers compact, interpretable models for quantities previously accessible only to black-box networks.
[805] MARTI-MARS$^2$: Scaling Multi-Agent Self-Search via Reinforcement Learning for Code Generation
Shijie Wang, Pengfei Li, Yikun Fu, Kaifeng Liu, Fangyuan Li, Yang Liu, Xiaowei Sun, Zonglin Li, Siyao Zhao, Jian Zhao, Kai Tian, Dong Li, Junqi Gao, Yutong Zhang, Yiqun Chen, Yuqiang Li, Zoe Li, Weinan Zhang, Peng Ye, Shuyue Hu, Lei Bai, Bowen Zhou, Kaiyan Zhang, Biqing Qi
Main category: cs.LG
TL;DR: MARTI-MARS2 is a multi-agent reinforcement learning framework that combines policy learning with tree search to enhance code generation performance through heterogeneous agent collaboration.
Details
Motivation: Single-agent LLMs face performance ceilings in complex tasks like code generation, while existing multi-agent approaches have limited error correction and strategic diversity due to prompt-based interactions or homogeneous parameter training.Method: Proposes MARTI-MARS2 framework that formulates multi-agent collaboration as a dynamic learnable environment, integrating policy learning with multi-agent tree search. Agents iteratively explore and refine, evolving from homogeneous to heterogeneous training. Also introduces MARTI-MARS2-T+ inference strategy for test-time scaling.
Result: Achieves 77.7% on code generation benchmarks using two collaborating 32B models, outperforming baselines like GPT-5.1. Reveals novel scaling law showing progressive improvement from single-agent to homogeneous to heterogeneous multi-agent paradigms.
Conclusion: Multi-agent reinforcement learning with policy diversity is critical for scaling intelligence, with heterogeneous multi-agent collaboration breaking through single-agent capability limits in complex reasoning tasks.
Abstract: While the complex reasoning capability of Large Language Models (LLMs) has attracted significant attention, single-agent systems often encounter inherent performance ceilings in complex tasks such as code generation. Multi-agent collaboration offers a promising avenue to transcend these boundaries. However, existing frameworks typically rely on prompt-based test-time interactions or multi-role configurations trained with homogeneous parameters, limiting error correction capabilities and strategic diversity. In this paper, we propose a Multi-Agent Reinforced Training and Inference Framework with Self-Search Scaling (MARTI-MARS2), which integrates policy learning with multi-agent tree search by formulating the multi-agent collaborative exploration process as a dynamic and learnable environment. By allowing agents to iteratively explore and refine within the environment, the framework facilitates evolution from parameter-sharing homogeneous multi-role training to heterogeneous multi-agent training, breaking through single-agent capability limits. We also introduce an efficient inference strategy MARTI-MARS2-T+ to fully exploit the scaling potential of multi-agent collaboration at test time. We conduct extensive experiments across varied model scales (8B, 14B, and 32B) on challenging code generation benchmarks. Utilizing two collaborating 32B models, MARTI-MARS2 achieves 77.7%, outperforming strong baselines like GPT-5.1. Furthermore, MARTI-MARS2 reveals a novel scaling law: shifting from single-agent to homogeneous multi-role and ultimately to heterogeneous multi-agent paradigms progressively yields higher RL performance ceilings, robust TTS capabilities, and greater policy diversity, suggesting that policy diversity is critical for scaling intelligence via multi-agent reinforcement learning.
[806] Safety Alignment as Continual Learning: Mitigating the Alignment Tax via Orthogonal Gradient Projection
Guanglong Sun, Siyuan Zhang, Liyuan Wang, Jun Zhu, Hang Su, Yi Zhong
Main category: cs.LG
TL;DR: OGPSA is a lightweight continual learning method that mitigates alignment tax in LLMs by projecting safety updates orthogonally to a learned subspace of general capabilities, preserving utility while improving safety.
Details
Motivation: Safety alignment in LLMs often causes an "alignment tax" where safety improvements reduce general utility (reasoning, coding). This arises from continual-learning-style forgetting during sequential alignment due to distribution shift and conflicting objectives.Method: Orthogonal Gradient Projection for Safety Alignment (OGPSA) estimates a low-rank capability subspace from gradients on a small reference set, then projects safety gradients onto its orthogonal complement before updating. This constrains safety updates to be orthogonal to general capabilities in a first-order sense.
Result: OGPSA consistently improves the safety-utility Pareto frontier across SFT, DPO, and sequential SFT→DPO settings. For Qwen2.5-7B-Instruct under SFT→DPO, it improves SimpleQA from 0.53% to 3.03% and IFEval from 51.94% to 63.96% while preserving safety.
Conclusion: OGPSA effectively mitigates alignment tax by treating safety alignment as a continual learning problem, balancing plasticity (safety acquisition) and stability (capability preservation) through orthogonal gradient projection.
Abstract: Large Language Models (LLMs) often incur an alignment tax: safety post-training can reduce general utility (e.g., reasoning and coding). We argue that this tax primarily arises from continual-learning-style forgetting in sequential alignment, where distribution shift and conflicting objectives cause safety updates to overwrite pre-trained competencies. Accordingly, we cast safety alignment as a continual learning (CL) problem that must balance plasticity (acquiring safety constraints) and stability (preserving general abilities). We propose Orthogonal Gradient Projection for Safety Alignment (OGPSA), a lightweight method that mitigates interference by constraining each safety update to be orthogonal (in a first-order sense) to a learned subspace capturing general capabilities. Specifically, OGPSA estimates a low-rank capability subspace from gradients on a small reference set and projects the safety gradient onto its orthogonal complement before updating. This produces safety-directed updates that minimally perturb prior knowledge while retaining capacity for alignment. OGPSA is plug-and-play and integrates into standard post-training pipelines without large-scale replay, auxiliary objectives, or retraining. Across Supervised Fine-Tuning (SFT), Direct Preference Optimization (DPO), and sequential SFT$\rightarrow$DPO settings, OGPSA consistently improves the safety–utility Pareto frontier over standard baselines. For instance, on Qwen2.5-7B-Instruct under SFT$\rightarrow$DPO, OGPSA preserves strong safety while recovering general capability, improving SimpleQA from 0.53% to 3.03% and IFEval from 51.94% to 63.96%. Our source code is available at \href{https://github.com/SunGL001/OGPSA}{OGPSA}
[807] Dynamic Load Model for Data Centers with Pattern-Consistent Calibration
Siyu Lu, Chenhan Xiao, Yang Weng
Main category: cs.LG
TL;DR: A framework combining physics-based structure with data-driven calibration for large electronic load modeling in power systems, using temporal contrastive learning to align temporal and statistical patterns from real operational data.
Details
Motivation: Existing data center load models have limitations: physics-based models lack calibration to facility-level operation, while data-driven methods often overfit and produce unrealistic dynamics due to trajectory alignment. There's a need for models that leverage both interpretable structure and empirical adaptability.Method: Parameterize physics-based structure to enable data-driven calibration using temporal contrastive learning (TCL) to align temporal and statistical patterns rather than trajectory-level alignment. Calibration is performed locally at facilities with only parameters shared to preserve privacy. Model is tested on real-world data from multiple supercomputing facilities and integrated into ANDES platform for power system evaluation.
Result: The calibrated model reveals that interactions among large electronic loads can fundamentally alter post-disturbance recovery behavior, producing compound disconnection-reconnection dynamics and delayed stabilization not captured by uncalibrated models.
Conclusion: The proposed framework successfully combines physics-based interpretability with data-driven calibration, addressing limitations of existing approaches and revealing important dynamic behaviors in power systems with large electronic loads.
Abstract: The rapid growth of data centers has made large electronic load (LEL) modeling increasingly important for power system analysis. Such loads are characterized by fast workload-driven variability and protection-driven disconnection and reconnection behavior that are not captured by conventional load models. Existing data center load modeling includes physics-based approaches, which provide interpretable structure for grid simulation, and data-driven approaches, which capture empirical workload variability from data. However, physics-based models are typically uncalibrated to facility-level operation, while trajectory alignment in data-driven methods often leads to overfitting and unrealistic dynamic behavior. To resolve these limitations, we design the framework to leverage both physics-based structure and data-driven adaptability. The physics-based structure is parameterized to enable data-driven pattern-consistent calibration from real operational data, supporting facility-level grid planning. We further show that trajectory-level alignment is limited for inherently stochastic data center loads. Therefore, we design the calibration to align temporal and statistical patterns using temporal contrastive learning (TCL). This calibration is performed locally at the facility, and only calibrated parameters are shared with utilities, preserving data privacy. The proposed load model is calibrated by real-world operational load data from the MIT Supercloud, ASU Sol, Blue Waters, and ASHRAE datasets. Then it is integrated into the ANDES platform and evaluated on the IEEE 39-bus, NPCC 140-bus, and WECC 179-bus systems. We find that interactions among LELs can fundamentally alter post-disturbance recovery behavior, producing compound disconnection-reconnection dynamics and delayed stabilization that are not captured by uncalibrated load models.
[808] Direct Soft-Policy Sampling via Langevin Dynamics
Donghyeon Ki, Hee-Jun Ahn, Kyungyoon Kim, Byung-Jun Lee
Main category: cs.LG
TL;DR: NC-LQL introduces noise-conditioned Langevin dynamics for soft policy sampling in RL, enabling efficient exploration-exploitation balance without explicit policy parameterization.
Details
Motivation: Existing soft policy approaches in RL face limitations: parametric policies have limited expressivity, while diffusion-based policies have intractable likelihoods that hinder reliable entropy estimation needed for soft policy objectives.Method: Proposes Noise-Conditioned Langevin Q-Learning (NC-LQL) which uses Langevin dynamics driven by Q-function gradients for soft policy sampling, enhanced with multi-scale noise perturbations to create progressively smoothed value landscapes for better exploration.
Result: NC-LQL achieves competitive performance on OpenAI Gym MuJoCo benchmarks compared to state-of-the-art diffusion-based methods, providing a simple yet effective solution for online RL.
Conclusion: NC-LQL offers a principled approach to realizing soft policies through noise-conditioned Langevin dynamics, addressing exploration challenges in high-dimensional RL problems without requiring explicit policy parameterization.
Abstract: Soft policies in reinforcement learning define policies as Boltzmann distributions over state-action value functions, providing a principled mechanism for balancing exploration and exploitation. However, realizing such soft policies in practice remains challenging. Existing approaches either depend on parametric policies with limited expressivity or employ diffusion-based policies whose intractable likelihoods hinder reliable entropy estimation in soft policy objectives. We address this challenge by directly realizing soft-policy sampling via Langevin dynamics driven by the action gradient of the Q-function. This perspective leads to Langevin Q-Learning (LQL), which samples actions from the target Boltzmann distribution without explicitly parameterizing the policy. However, directly applying Langevin dynamics suffers from slow mixing in high-dimensional and non-convex Q-landscapes, limiting its practical effectiveness. To overcome this, we propose Noise-Conditioned Langevin Q-Learning (NC-LQL), which integrates multi-scale noise perturbations into the value function. NC-LQL learns a noise-conditioned Q-function that induces a sequence of progressively smoothed value landscapes, enabling sampling to transition from global exploration to precise mode refinement. On OpenAI Gym MuJoCo benchmarks, NC-LQL achieves competitive performance compared to state-of-the-art diffusion-based methods, providing a simple yet powerful solution for online RL.
[809] Implicit Strategic Optimization: Rethinking Long-Horizon Decision-Making in Adversarial Poker Environments
Boyang Xia, Weiyou Tian, Qingnan Ren, Jiaqi Huang, Jie Xiao, Shuo Lu, Kai Wang, Lynn Ai, Eric Yang, Bill Shi
Main category: cs.LG
TL;DR: ISO framework enables LLM agents to optimize long-term strategic value in adversarial games by forecasting strategic contexts and using context-conditioned optimistic learning.
Details
Motivation: Episodic objectives like win rate fail in long-horizon adversarial games where strategic externalities evolve over time, making myopic optimization and variation-based regret analyses ineffective even when dynamics are predictable.Method: Introduces Implicit Strategic Optimization (ISO) with Strategic Reward Model (SRM) to estimate long-run strategic value of actions, combined with iso-grpo, a context-conditioned optimistic learning rule for online policy updates based on forecasted strategic contexts.
Result: Proves sublinear contextual regret and equilibrium convergence guarantees scaling with context mispredictions; experiments in 6-player No-Limit Texas Hold’em and competitive Pokemon show consistent improvements in long-term return over LLM/RL baselines and graceful degradation under prediction noise.
Conclusion: ISO provides a principled framework for LLM agents to optimize long-term strategic value in adversarial games by incorporating strategic context forecasting, with theoretical guarantees and empirical improvements over existing methods.
Abstract: Training large language model (LLM) agents for adversarial games is often driven by episodic objectives such as win rate. In long-horizon settings, however, payoffs are shaped by latent strategic externalities that evolve over time, so myopic optimization and variation-based regret analyses can become vacuous even when the dynamics are predictable. To solve this problem, we introduce Implicit Strategic Optimization (ISO), a prediction-aware framework in which each agent forecasts the current strategic context and uses it to update its policy online. ISO combines a Strategic Reward Model (SRM) that estimates the long-run strategic value of actions with iso-grpo, a context-conditioned optimistic learning rule. We prove sublinear contextual regret and equilibrium convergence guarantees whose dominant terms scale with the number of context mispredictions; when prediction errors are bounded, our bounds recover the static-game rates obtained when strategic externalities are known. Experiments in 6-player No-Limit Texas Hold’em and competitive Pokemon show consistent improvements in long-term return over strong LLM and RL baselines, and graceful degradation under controlled prediction noise.
[810] Harpoon: Generalised Manifold Guidance for Conditional Tabular Diffusion
Aditya Shankar, Yuandou Wang, Rihan Hai, Lydia Y. Chen
Main category: cs.LG
TL;DR: HARPOON is a tabular diffusion method that uses manifold theory to guide unconstrained samples to satisfy diverse tabular conditions at inference time, handling tasks beyond imputation like inequality constraints.
Details
Motivation: Existing tabular data generation methods don't generalize to unseen constraints during inference and struggle with conditional tasks beyond imputation. Current manifold theory approaches are tied to specific objectives and limited to continuous domains.Method: Extends manifold theory to tabular data and introduces HARPOON, a tabular diffusion method that guides unconstrained samples along manifold geometry to satisfy diverse tabular conditions at inference time.
Result: Demonstrates strong performance on tasks like imputation and enforcing inequality constraints across diverse datasets, showing practical benefits of manifold-aware guidance for tabular data.
Conclusion: HARPOON successfully applies manifold theory to tabular data generation, enabling flexible inference-time conditioning for diverse constraints beyond what existing methods can handle.
Abstract: Generating tabular data under conditions is critical to applications requiring precise control over the generative process. Existing methods rely on training-time strategies that do not generalise to unseen constraints during inference, and struggle to handle conditional tasks beyond tabular imputation. While manifold theory offers a principled way to guide generation, current formulations are tied to specific inference-time objectives and are limited to continuous domains. We extend manifold theory to tabular data and expand its scope to handle diverse inference-time objectives. On this foundation, we introduce HARPOON, a tabular diffusion method that guides unconstrained samples along the manifold geometry to satisfy diverse tabular conditions at inference. We validate our theoretical contributions empirically on tasks such as imputation and enforcing inequality constraints, demonstrating HARPOON’S strong performance across diverse datasets and the practical benefits of manifold-aware guidance for tabular data. Code URL: https://github.com/adis98/Harpoon
[811] SiameseNorm: Breaking the Barrier to Reconciling Pre/Post-Norm
Tianyu Li, Dongchen Han, Zixuan Cao, Haofeng Huang, Mengyu Zhou, Ming Chen, Erchao Zhao, Xiaoxi Jiang, Guanjun Jiang, Gao Huang
Main category: cs.LG
TL;DR: SiameseNorm is a two-stream Transformer architecture that combines Pre-Norm stability with Post-Norm expressivity by decoupling optimization dynamics through parameter sharing between streams.
Details
Motivation: Modern Transformers use Pre-Norm for stability but sacrifice Post-Norm's superior potential. Prior attempts to combine them lead to stability-performance trade-offs due to structural incompatibility in single-stream designs where Post-Norm obstructs Pre-Norm's clean identity gradient.Method: Proposes SiameseNorm, a two-stream architecture coupling Pre-Norm-like and Post-Norm-like streams with shared parameters. This decouples optimization dynamics, allowing all residual blocks to receive combined gradients from both paradigms - one stream ensures stability while the other enhances expressivity.
Result: Extensive pre-training experiments on 1.3B-parameter models show SiameseNorm exhibits exceptional optimization robustness and consistently outperforms strong baselines.
Conclusion: SiameseNorm fundamentally reconciles Pre-Norm and Post-Norm paradigms through a two-stream design, achieving both stability and superior performance in large-scale Transformer models.
Abstract: Modern Transformers predominantly adopt the Pre-Norm paradigm for its optimization stability, foregoing the superior potential of the unstable Post-Norm architecture. Prior attempts to combine their strengths typically lead to a stability-performance trade-off. We attribute this phenomenon to a structural incompatibility within a single-stream design: Any application of the Post-Norm operation inevitably obstructs the clean identity gradient preserved by Pre-Norm. To fundamentally reconcile these paradigms, we propose SiameseNorm, a two-stream architecture that couples Pre-Norm-like and Post-Norm-like streams with shared parameters. This design decouples the optimization dynamics of the two streams, retaining the distinct characteristics of both Pre-Norm and Post-Norm by enabling all residual blocks to receive combined gradients inherited from both paradigms, where one stream secures stability while the other enhances expressivity. Extensive pre-training experiments on 1.3B-parameter models demonstrate that SiameseNorm exhibits exceptional optimization robustness and consistently outperforms strong baselines. Code is available at https://github.com/Qwen-Applications/SiameseNorm.
[812] GRAFT: Decoupling Ranking and Calibration for Survival Analysis
Mohammad Ashhad, Robert Hoehndorf, Ricardo Henao
Main category: cs.LG
TL;DR: GRAFT is a hybrid survival analysis model combining linear AFT with non-linear neural networks and stochastic gates for feature selection, trained with C-index-aligned ranking loss.
Details
Motivation: Survival analysis faces challenges with censored data, high-dimensional features, and non-linear interactions. Classical models are interpretable but restrictive, while deep learning models are flexible but often non-interpretable and sensitive to noise.Method: GRAFT decouples prognostic ranking from calibration using a hybrid architecture: linear AFT model + non-linear residual neural network + stochastic gates for feature selection. Trained with differentiable C-index-aligned ranking loss using stochastic conditional imputation from local Kaplan-Meier estimators.
Result: Outperforms baselines in discrimination and calibration on public benchmarks, while remaining robust and sparse in high-noise settings.
Conclusion: GRAFT provides an effective hybrid approach to survival analysis that balances interpretability, flexibility, and robustness through its decoupled architecture and feature selection capabilities.
Abstract: Survival analysis is complicated by censored data, high-dimensional features, and non-linear interactions. Classical models are interpretable but restrictive, while deep learning models are flexible but often non-interpretable and sensitive to noise. We propose GRAFT (Gated Residual Accelerated Failure Time), a novel AFT model that decouples prognostic ranking from calibration. GRAFT’s hybrid architecture combines a linear AFT model with a non-linear residual neural network, and it also integrates stochastic gates for automatic, end-to-end feature selection. The model is trained by directly optimizing a differentiable, C-index-aligned ranking loss using stochastic conditional imputation from local Kaplan-Meier estimators. In public benchmarks, GRAFT outperforms baselines in discrimination and calibration, while remaining robust and sparse in high-noise settings.
[813] Online Bayesian Imbalanced Learning with Bregman-Calibrated Deep Networks
Zahir Alsulaimawi
Main category: cs.LG
TL;DR: OBIL is an online Bayesian framework for handling class imbalance that enables real-time adaptation to distribution shifts without retraining by decoupling likelihood-ratio estimation from class-prior assumptions.
Details
Motivation: Class imbalance is a fundamental challenge in ML, and existing approaches require retraining or labeled target data when class distributions shift at deployment time, which is common in real-world applications like fraud detection and medical diagnosis.Method: OBIL leverages the connection between Bregman divergences and proper scoring rules to show that deep networks trained with such losses produce posterior probability estimates from which prior-invariant likelihood ratios can be extracted. The framework decouples likelihood-ratio estimation from class-prior assumptions.
Result: Theoretical analysis proves likelihood-ratio estimates remain valid under arbitrary changes in class priors and cost structures, requiring only threshold adjustment. Finite-sample regret bounds show OBIL achieves O(√(T log T)) regret. Experiments demonstrate OBIL maintains robust performance under severe distribution shifts, outperforming state-of-the-art methods in F1 Score when test distributions deviate significantly from training conditions.
Conclusion: OBIL provides a principled framework for online imbalanced learning that enables real-time adaptation to distribution shifts without model retraining, addressing a key limitation of existing approaches in practical deployment scenarios.
Abstract: Class imbalance remains a fundamental challenge in machine learning, where standard classifiers exhibit severe performance degradation in minority classes. Although existing approaches address imbalance through resampling or cost-sensitive learning during training, they require retraining or access to labeled target data when class distributions shift at deployment time, a common occurrence in real-world applications such as fraud detection, medical diagnosis, and anomaly detection. We present \textit{Online Bayesian Imbalanced Learning} (OBIL), a principled framework that decouples likelihood-ratio estimation from class-prior assumptions, enabling real-time adaptation to distribution shifts without model retraining. Our approach builds on the established connection between Bregman divergences and proper scoring rules to show that deep networks trained with such losses produce posterior probability estimates from which prior-invariant likelihood ratios can be extracted. We prove that these likelihood-ratio estimates remain valid under arbitrary changes in class priors and cost structures, requiring only a threshold adjustment for optimal Bayes decisions. We derive finite-sample regret bounds demonstrating that OBIL achieves $O(\sqrt{T \log T})$ regret against an oracle with perfect prior knowledge. Extensive experiments on benchmark datasets and medical diagnosis benchmarks under simulated deployment shifts demonstrate that OBIL maintains robust performance under severe distribution shifts, outperforming state-of-the-art methods in F1 Score when test distributions deviate significantly from the training conditions.
[814] Efficient Anti-exploration via VQVAE and Fuzzy Clustering in Offline Reinforcement Learning
Long Chen, Yinkui Liu, Shen Li, Bo Tang, Xuemin Hu
Main category: cs.LG
TL;DR: A novel anti-exploration method for offline RL using VQVAE and fuzzy clustering to count continuous state-action pairs efficiently without dimension disaster or information loss issues.
Details
Motivation: Existing anti-exploration methods in offline RL discretize continuous state-action pairs for counting, but suffer from dimension disaster and information loss during discretization, leading to reduced efficiency, performance degradation, and even policy learning failure.Method: Proposes a VQVAE-based pseudo-count method with multi-codebook architecture to discretize state-action pairs efficiently. Uses fuzzy C-means clustering for codebook updates to improve vector utilization and address information loss. Integrates this into an offline RL anti-exploitation framework.
Result: Evaluated on D4RL benchmark; shows better performance with less computing cost compared to SOTA methods across multiple complex tasks.
Conclusion: The proposed VQVAE and fuzzy clustering-based anti-exploration method effectively addresses dimension disaster and information loss issues in offline RL, achieving superior performance with reduced computational requirements.
Abstract: Pseudo-count is an effective anti-exploration method in offline reinforcement learning (RL) by counting state-action pairs and imposing a large penalty on rare or unseen state-action pair data. Existing anti-exploration methods count continuous state-action pairs by discretizing these data, but often suffer from the issues of dimension disaster and information loss in the discretization process, leading to efficiency and performance reduction, and even failure of policy learning. In this paper, a novel anti-exploration method based on Vector Quantized Variational Autoencoder (VQVAE) and fuzzy clustering in offline RL is proposed. We first propose an efficient pseudo-count method based on the multi-codebook VQVAE to discretize state-action pairs, and design an offline RL anti-exploitation method based on the proposed pseudo-count method to handle the dimension disaster issue and improve the learning efficiency. In addition, a codebook update mechanism based on fuzzy C-means (FCM) clustering is developed to improve the use rate of vectors in codebooks, addressing the information loss issue in the discretization process. The proposed method is evaluated on the benchmark of Datasets for Deep Data-Driven Reinforcement Learning (D4RL), and experimental results show that the proposed method performs better and requires less computing cost in multiple complex tasks compared to state-of-the-art (SOTA) methods.
[815] Reliable and Responsible Foundation Models: A Comprehensive Survey
Xinyu Yang, Junlin Han, Rishi Bommasani, Jinqi Luo, Wenjie Qu, Wangchunshu Zhou, Adel Bibi, Xiyao Wang, Jaehong Yoon, Elias Stengel-Eskin, Shengbang Tong, Lingfeng Shen, Rafael Rafailov, Runjia Li, Zhaoyang Wang, Yiyang Zhou, Chenhang Cui, Yu Wang, Wenhao Zheng, Huichi Zhou, Jindong Gu, Zhaorun Chen, Peng Xia, Tony Lee, Thomas Zollo, Vikash Sehwag, Jixuan Leng, Jiuhai Chen, Yuxin Wen, Huan Zhang, Zhun Deng, Linjun Zhang, Pavel Izmailov, Pang Wei Koh, Yulia Tsvetkov, Andrew Wilson, Jiaheng Zhang, James Zou, Cihang Xie, Hao Wang, Philip Torr, Julian McAuley, David Alvarez-Melis, Florian Tramèr, Kaidi Xu, Suman Jana, Chris Callison-Burch, Rene Vidal, Filippos Kokkinos, Mohit Bansal, Beidi Chen, Huaxiu Yao
Main category: cs.LG
TL;DR: Survey paper on reliability and responsibility issues in foundation models (LLMs, MLLMs, image/video generative models) covering bias, security, uncertainty, explainability, distribution shift, hallucinations, alignment, and AIGC detection.
Details
Motivation: Foundation models are increasingly deployed in real-world applications across critical domains, making their reliability and responsibility crucial for academia, industry, and government. There's a need to systematically address ethical and trustworthy development of these powerful AI systems.Method: Comprehensive survey methodology reviewing current research across multiple reliability dimensions: bias/fairness, security/privacy, uncertainty, explainability, distribution shift, model limitations (hallucinations), alignment techniques, and AIGC detection methods.
Result: Provides systematic review of current state in each reliability area, identifies intersections between different research directions, and outlines concrete future research directions for developing more ethical and trustworthy foundation models.
Conclusion: The survey aims to foster development of foundation models that are not only powerful but also ethical, trustworthy, reliable, and socially responsible by providing comprehensive overview of reliability challenges and research directions.
Abstract: Foundation models, including Large Language Models (LLMs), Multimodal Large Language Models (MLLMs), Image Generative Models (i.e, Text-to-Image Models and Image-Editing Models), and Video Generative Models, have become essential tools with broad applications across various domains such as law, medicine, education, finance, science, and beyond. As these models see increasing real-world deployment, ensuring their reliability and responsibility has become critical for academia, industry, and government. This survey addresses the reliable and responsible development of foundation models. We explore critical issues, including bias and fairness, security and privacy, uncertainty, explainability, and distribution shift. Our research also covers model limitations, such as hallucinations, as well as methods like alignment and Artificial Intelligence-Generated Content (AIGC) detection. For each area, we review the current state of the field and outline concrete future research directions. Additionally, we discuss the intersections between these areas, highlighting their connections and shared challenges. We hope our survey fosters the development of foundation models that are not only powerful but also ethical, trustworthy, reliable, and socially responsible.
[816] Adaptive Acquisition Selection for Bayesian Optimization with Large Language Models
Giang Ngo, Dat Phan Trong, Dang Nguyen, Sunil Gupta, Svetha Venkatesh
Main category: cs.LG
TL;DR: LMABO uses a pre-trained LLM as a zero-shot strategist to dynamically select the best acquisition function for Bayesian Optimization from a portfolio, outperforming static and adaptive baselines.
Details
Motivation: Bayesian Optimization needs adaptive acquisition function selection, but existing methods ignore rich contextual information like remaining budget and model characteristics, relying only on past function values.Method: LMABO frames an LLM as a zero-shot online strategist that uses structured state representations (including optimization progress, surrogate model info, and remaining budget) to select acquisition functions from a diverse portfolio at each iteration.
Result: Across 50 benchmark problems, LMABO significantly outperforms static strategies, adaptive portfolio methods, and other LLM-based baselines, demonstrating superior optimization performance.
Conclusion: LLMs can effectively synthesize complete optimization state information into adaptive policies for acquisition function selection, proving their advantage comes from processing rich contextual information rather than just past performance.
Abstract: Bayesian Optimization critically depends on the choice of acquisition function, but no single strategy is universally optimal; the best choice is non-stationary and problem-dependent. Existing adaptive portfolio methods often base their decisions on past function values while ignoring richer information like remaining budget or surrogate model characteristics. To address this, we introduce LMABO, a novel framework that casts a pre-trained Large Language Model (LLM) as a zero-shot, online strategist for the BO process. At each iteration, LMABO uses a structured state representation to prompt the LLM to select the most suitable acquisition function from a diverse portfolio. In an evaluation across 50 benchmark problems, LMABO demonstrates a significant performance improvement over strong static, adaptive portfolio, and other LLM-based baselines. We show that the LLM’s behavior is a comprehensive strategy that adapts to real-time progress, proving its advantage stems from its ability to process and synthesize the complete optimization state into an effective, adaptive policy.
[817] The Confidence Manifold: Geometric Structure of Correctness Representations in Language Models
Seonglae Cho, Zekun Wu, Kleyton Da Costa, Adriano Koshiyama
Main category: cs.LG
TL;DR: The paper analyzes the geometric structure of correctness representations in language models, finding that correctness signals exist in low-dimensional subspaces (3-8 dimensions) and can be detected using simple linear classifiers or centroid distances, with internal probes significantly outperforming output-based methods.
Details
Motivation: To understand whether language models internally know when they're making incorrect statements, and to characterize the geometric structure of correctness representations across different model architectures.Method: Analyzed 9 models from 5 architecture families, examining the geometry of correctness representations using linear and nonlinear classifiers, few-shot detection with centroid distances, and causal validation through activation steering experiments.
Result: Found that correctness signals occupy only 3-8 dimensions, performance degrades with additional dimensions, and linear separation is optimal. Centroid distance achieves 0.90 AUC, enabling few-shot detection (89% of full-data accuracy with 25 examples). Activation steering produces 10.9 percentage point changes in error rates. Internal probes achieve 0.80-0.97 AUC while output-based methods only achieve 0.44-0.64 AUC.
Conclusion: Language models do have internal representations of correctness, but these signals are not expressed in their outputs. The geometric structure is simple, with class separation being a mean shift, making detection geometric rather than learned.
Abstract: When a language model asserts that “the capital of Australia is Sydney,” does it know this is wrong? We characterize the geometry of correctness representations across 9 models from 5 architecture families. The structure is simple: the discriminative signal occupies 3-8 dimensions, performance degrades with additional dimensions, and no nonlinear classifier improves over linear separation. Centroid distance in the low-dimensional subspace matches trained probe performance (0.90 AUC), enabling few-shot detection: on GPT-2, 25 labeled examples achieve 89% of full-data accuracy. We validate causally through activation steering: the learned direction produces 10.9 percentage point changes in error rates while random directions show no effect. Internal probes achieve 0.80-0.97 AUC; output-based methods (P(True), semantic entropy) achieve only 0.44-0.64 AUC. The correctness signal exists internally but is not expressed in outputs. That centroid distance matches probe performance indicates class separation is a mean shift, making detection geometric rather than learned.
[818] AceGRPO: Adaptive Curriculum Enhanced Group Relative Policy Optimization for Autonomous Machine Learning Engineering
Yuzhu Cai, Zexi Liu, Xinyu Zhu, Cheng Wang, Jiaao Chen, Hanrui Wang, Wei-Chen Wang, Di Jin, Siheng Chen
Main category: cs.LG
TL;DR: AceGRPO is an RL-based framework for autonomous ML engineering that uses evolving data buffers and adaptive sampling to enable sustained iterative optimization, achieving 100% valid submission rate on MLE-Bench-Lite.
Details
Motivation: Current LLM-based agents for autonomous ML engineering suffer from behavioral stagnation due to frozen parameters, while RL approaches face prohibitive execution latency and inefficient data selection challenges.Method: Proposes AceGRPO with two core components: (1) Evolving Data Buffer that repurposes execution traces into reusable training tasks, and (2) Adaptive Sampling guided by a Learnability Potential function that prioritizes tasks at the agent’s learning frontier.
Result: The trained Ace-30B model achieves 100% valid submission rate on MLE-Bench-Lite, approaches performance of proprietary frontier models, and outperforms larger open-source baselines like DeepSeek-V3.2.
Conclusion: AceGRPO demonstrates robust capability for sustained iterative optimization in autonomous ML engineering, addressing key limitations of current prompt-based and RL approaches.
Abstract: Autonomous Machine Learning Engineering (MLE) requires agents to perform sustained, iterative optimization over long horizons. While recent LLM-based agents show promise, current prompt-based agents for MLE suffer from behavioral stagnation due to frozen parameters. Although Reinforcement Learning (RL) offers a remedy, applying it to MLE is hindered by prohibitive execution latency and inefficient data selection. Recognizing these challenges, we propose AceGRPO with two core components: (1) Evolving Data Buffer that continuously repurposes execution traces into reusable training tasks, and (2) Adaptive Sampling guided by a Learnability Potential function, which dynamically prioritizes tasks at the agent’s learning frontier to maximize learning efficiency. Leveraging AceGRPO, our trained Ace-30B model achieves a 100% valid submission rate on MLE-Bench-Lite, approaches the performance of proprietary frontier models, and outperforms larger open-source baselines (e.g., DeepSeek-V3.2), demonstrating robust capability for sustained iterative optimization. Code is available at https://github.com/yuzhu-cai/AceGRPO.
[819] Spherical Steering: Geometry-Aware Activation Rotation for Language Models
Zejia You, Chunyuan Deng, Hanjie Chen
Main category: cs.LG
TL;DR: Spherical Steering is a training-free inference-time control method that uses activation rotation instead of addition to steer language models while preserving representation norms and open-ended generation quality.
Details
Motivation: Standard inference-time steering methods like activation addition alter the magnitude of hidden representations, causing representation collapse and degradation of open-ended generation capabilities. The authors aim to develop a method that provides precise control without these drawbacks.Method: Proposes Spherical Steering, which rotates activations along a geodesic toward a target direction instead of adding fixed vectors. Incorporates a confidence gate that dynamically modulates steering strength based on input uncertainty. The method is training-free and preserves activation norms.
Result: Significantly outperforms addition-based baselines (+10% on TruthfulQA, COPA, and Storycloze benchmarks) while maintaining the model’s general open-ended generation quality. Demonstrates the effectiveness of norm-preserving rotation for precise inference-time control.
Conclusion: Spherical Steering resolves the trade-off between control and generation quality by using geometric consistency through activation rotation. Norm-preserving rotation is a robust and effective primitive for precise inference-time control of language models.
Abstract: Inference-time steering has emerged as a promising paradigm for controlling language models (LMs) without the cost of retraining. However, standard approaches typically rely on activation addition, a geometric operation that inevitably alters the magnitude of hidden representations. This raises concerns about representation collapse and degradation of open-ended generation capabilities. In this work, we explore Spherical Steering, a training-free primitive that resolves this trade-off through activation rotation. Rather than shifting activations with a fixed vector, our method rotates them along a geodesic toward a target direction, guiding the activation toward the target concept while preserving the integrity of the signal. To further enhance adaptivity, we incorporate a confidence gate that dynamically modulates steering strength based on input uncertainty. Extensive experiments across multiple-choice benchmarks demonstrate that Spherical Steering significantly outperforms addition-based baselines (notably by +10% on TruthfulQA, COPA, and Storycloze), while simultaneously maintaining the model’s general open-ended generation quality. This work highlights the value of geometric consistency, suggesting that norm-preserving rotation is a robust and effective primitive for precise inference-time control.
[820] CausalCompass: Evaluating the Robustness of Time-Series Causal Discovery in Misspecified Scenarios
Huiyang Yi, Xiaojian Shen, Yonggang Wu, Duxin Chen, He Wang, Wenwu Yu
Main category: cs.LG
TL;DR: CausalCompass is a benchmark suite for evaluating robustness of time-series causal discovery methods under violations of modeling assumptions, showing deep learning methods perform best overall.
Details
Motivation: Current time-series causal discovery methods rely on untestable causal assumptions and lack robustness-oriented evaluation, hindering their widespread adoption in real-world applications.Method: Proposes CausalCompass benchmark suite with eight assumption-violation scenarios, extensively evaluates representative TSCD algorithms, and provides hyperparameter sensitivity analyses.
Result: No single method performs optimally across all settings, but deep learning-based approaches show superior overall performance. NTS-NOTEARS heavily depends on standardized preprocessing.
Conclusion: CausalCompass provides comprehensive evaluation of TSCD methods under assumption violations to facilitate broader real-world adoption, with deep learning methods showing best robustness.
Abstract: Causal discovery from time series is a fundamental task in machine learning. However, its widespread adoption is hindered by a reliance on untestable causal assumptions and by the lack of robustness-oriented evaluation in existing benchmarks. To address these challenges, we propose CausalCompass, a flexible and extensible benchmark suite designed to assess the robustness of time-series causal discovery (TSCD) methods under violations of modeling assumptions. To demonstrate the practical utility of CausalCompass, we conduct extensive benchmarking of representative TSCD algorithms across eight assumption-violation scenarios. Our experimental results indicate that no single method consistently attains optimal performance across all settings. Nevertheless, the methods exhibiting superior overall performance across diverse scenarios are almost invariably deep learning-based approaches. We further provide hyperparameter sensitivity analyses to deepen the understanding of these findings. We also find, somewhat surprisingly, that NTS-NOTEARS relies heavily on standardized preprocessing in practice, performing poorly in the vanilla setting but exhibiting strong performance after standardization. Finally, our work aims to provide a comprehensive and systematic evaluation of TSCD methods under assumption violations, thereby facilitating their broader adoption in real-world applications. The code and datasets are available at https://github.com/huiyang-yi/CausalCompass.
[821] Dreaming in Code for Curriculum Learning in Open-Ended Worlds
Konstantinos Mitsides, Maxence Faldor, Antoine Cully
Main category: cs.LG
TL;DR: Dreaming in Code (DiCode) uses foundation models to generate executable environment code as a curriculum for open-ended learning, enabling agents to acquire long-horizon skills in complex worlds like Craftax.
Details
Motivation: Open-ended learning requires agents to navigate ever-expanding spaces of environments, but current approaches struggle to orchestrate sustained progression and discover sequences of learnable experiences in complex combinatorial spaces.Method: DiCode framework where foundation models synthesize executable environment code to scaffold learning toward increasing competence. The “dreaming” process materializes code-level variations of the world to create intermediate environments that bridge competence gaps.
Result: DiCode achieves 16% improvement in mean return over strongest baselines and non-zero success on late-game combat tasks where prior methods fail, enabling acquisition of long-horizon skills in the Craftax benchmark.
Conclusion: Code-level environment design provides a practical mechanism for curriculum control in open-ended worlds, allowing construction of intermediate environments that bridge competence gaps through foundation model-generated code variations.
Abstract: Open-ended learning frames intelligence as emerging from continual interaction with an ever-expanding space of environments. While recent advances have utilized foundation models to programmatically generate diverse environments, these approaches often focus on discovering isolated behaviors rather than orchestrating sustained progression. In complex open-ended worlds, the large combinatorial space of possible challenges makes it difficult for agents to discover sequences of experiences that remain consistently learnable. To address this, we propose Dreaming in Code (DiCode), a framework in which foundation models synthesize executable environment code to scaffold learning toward increasing competence. In DiCode, “dreaming” takes the form of materializing code-level variations of the world. We instantiate DiCode in Craftax, a challenging open-ended benchmark characterized by rich mechanics and long-horizon progression. Empirically, DiCode enables agents to acquire long-horizon skills, achieving a $16%$ improvement in mean return over the strongest baseline and non-zero success on late-game combat tasks where prior methods fail. Our results suggest that code-level environment design provides a practical mechanism for curriculum control, enabling the construction of intermediate environments that bridge competence gaps in open-ended worlds. Project page and source code are available at https://konstantinosmitsides.github.io/dreaming-in-code and https://github.com/konstantinosmitsides/dreaming-in-code.
[822] A Kinetic-Energy Perspective of Flow Matching
Ziyun Li, Huancheng Hu, Soon Hoe Lim, Xuyu Li, Fei Gao, Enmao Diao, Zezhen Ding, Michalis Vazirgiannis, Henrik Bostrom
Main category: cs.LG
TL;DR: Flow-based generative models analyzed through physics lens; Kinetic Path Energy (KPE) introduced as action-like diagnostic for ODE trajectories; KPE correlates with semantic fidelity and low-density frontiers; extreme energies cause memorization; Kinetic Trajectory Shaping (KTS) proposed as training-free inference strategy.
Details
Motivation: To understand flow-based generative models from a physics perspective and develop diagnostic tools for analyzing trajectory dynamics, addressing issues like memorization and improving generation quality.Method: Introduces Kinetic Path Energy (KPE) as a per-sample diagnostic measuring accumulated kinetic effort along ODE trajectories in flow-based models. Provides theoretical analysis linking trajectory energy to data density. Proposes Kinetic Trajectory Shaping (KTS) - a two-phase inference strategy that boosts early motion and enforces late-time soft landing.
Result: KPE exhibits robust correspondences: higher KPE predicts stronger semantic fidelity, and high-KPE trajectories terminate on low-density manifold frontiers. Shows that extreme energies can cause memorization (near-copies of training examples). KTS reduces memorization and improves generation quality across benchmark tasks.
Conclusion: Flow-based generative models can be effectively analyzed through physics principles. KPE serves as a valuable diagnostic tool, revealing a Goldilocks principle for trajectory energies. KTS offers a practical training-free method to improve generation quality by balancing trajectory dynamics.
Abstract: Flow-based generative models can be viewed through a physics lens: sampling transports a particle from noise to data by integrating a time-varying velocity field, and each sample corresponds to a trajectory with its own dynamical effort. Motivated by classical mechanics, we introduce Kinetic Path Energy (KPE), an action-like, per-sample diagnostic that measures the accumulated kinetic effort along an Ordinary Differential Equation (ODE) trajectory. Empirically, KPE exhibits two robust correspondences: (i) higher KPE predicts stronger semantic fidelity; (ii) high-KPE trajectories terminate on low-density manifold frontiers. We further provide theoretical guarantees linking trajectory energy to data density. Paradoxically, this correlation is non-monotonic. At sufficiently high energy, generation can degenerate into memorization. Leveraging the closed-form of empirical flow matching, we show that extreme energies drive trajectories toward near-copies of training examples. This yields a Goldilocks principle and motivates Kinetic Trajectory Shaping (KTS), a training-free two-phase inference strategy that boosts early motion and enforces a late-time soft landing, reducing memorization and improving generation quality across benchmark tasks.
[823] DrugR: Optimizing Molecular Drugs through LLM-based Explicit Reasoning
Haoran Liu, Zheni Zeng, Yukun Yan, Yuxuan Chen, Yunduo Xiao
Main category: cs.LG
TL;DR: DrugR is an LLM-based method for molecule optimization that introduces explicit pharmacological reasoning through domain-specific pretraining, reverse data engineering fine-tuning, and self-balanced multi-granular reinforcement learning.
Details
Motivation: Current LLMs struggle with the complex implicit relationship between molecular structure and pharmacological properties, and lack labeled data for molecule optimization. There's a need for interpretable, knowledge-driven approaches to molecular design.Method: Three-stage framework: 1) Domain-specific continual pretraining on chemical knowledge, 2) Supervised fine-tuning via reverse data engineering to learn optimization patterns, 3) Self-balanced multi-granular reinforcement learning to optimize multiple ADMET properties simultaneously while preserving core efficacy.
Result: DrugR achieves comprehensive enhancement across multiple ADMET properties without compromising structural similarity or target binding affinity. It provides interpretable rationales for each optimization step.
Conclusion: DrugR advances automated, knowledge-driven scientific discovery in chemistry by enabling explicit pharmacological reasoning in molecule optimization, with open-sourced code and models to foster future research.
Abstract: Molecule generation and optimization is a fundamental task in chemical domain. The rapid development of intelligent tools, especially large language models (LLMs) with powerful knowledge reserves and interactive capabilities, has provided new paradigms for it. Nevertheless, the intrinsic challenge for LLMs lies in the complex implicit relationship between molecular structure and pharmacological properties and the lack of corresponding labeled data. To bridge this gap, we propose DrugR, an LLM-based method that introduces explicit, step-by-step pharmacological reasoning into the optimization process. Our approach integrates domain-specific continual pretraining, supervised fine-tuning via reverse data engineering, and self-balanced multi-granular reinforcement learning. This framework enables DrugR to effectively improve key ADMET properties while preserving the original molecule’s core efficacy. Experimental results demonstrate that DrugR achieves comprehensive enhancement across multiple properties without compromising structural similarity or target binding affinity. Importantly, its explicit reasoning process provides clear, interpretable rationales for each optimization step, yielding actionable design insights and advancing toward automated, knowledge-driven scientific discovery. Our code and model checkpoints are open-sourced to foster future research.
[824] Attention-Based Deep Learning for Early Parkinson’s Disease Detection with Tabular Biomedical Data
Olamide Samuel Oseni, Ibraheem Omotolani Obanla, Toheeb Aduramomi Jimoh
Main category: cs.LG
TL;DR: Attention-based deep learning models, particularly SAINT, outperform traditional ML methods for early Parkinson’s disease detection using biomedical voice data, achieving near-perfect classification metrics.
Details
Motivation: Early and accurate detection of Parkinson's disease is challenging due to subtle early-stage symptoms and complex non-linear relationships in biomedical data. Traditional ML models require extensive feature engineering and struggle with complex feature interactions.Method: Comparative evaluation of four classification models (MLP, Gradient Boosting, TabNet, and SAINT) using a benchmark dataset from UCI Machine Learning Repository containing biomedical voice measurements from PD patients and healthy controls.
Result: SAINT consistently outperformed all baseline models, achieving weighted precision of 0.98, recall of 0.97, F1-score of 0.97, MCC of 0.9990, and highest AUC-ROC. TabNet and MLP showed competitive performance, while Gradient Boosting performed worst.
Conclusion: Attention-based deep learning architectures like SAINT demonstrate strong diagnostic potential for early Parkinson’s disease detection, highlighting the importance of dynamic feature representation in clinical prediction tasks.
Abstract: Early and accurate detection of Parkinson’s disease (PD) remains a critical challenge in medical diagnostics due to the subtlety of early-stage symptoms and the complex, non-linear relationships inherent in biomedical data. Traditional machine learning (ML) models, though widely applied to PD detection, often rely on extensive feature engineering and struggle to capture complex feature interactions. This study investigates the effectiveness of attention-based deep learning models for early PD detection using tabular biomedical data. We present a comparative evaluation of four classification models: Multi-Layer Perceptron (MLP), Gradient Boosting, TabNet, and SAINT, using a benchmark dataset from the UCI Machine Learning Repository consisting of biomedical voice measurements from PD patients and healthy controls. Experimental results show that SAINT consistently outperformed all baseline models across multiple evaluation metrics, achieving a weighted precision of 0.98, weighted recall of 0.97, weighted F1-score of 0.97, a Matthews Correlation Coefficient (MCC) of 0.9990, and the highest Area Under the ROC Curve (AUC-ROC). TabNet and MLP demonstrated competitive performance, while Gradient Boosting yielded the lowest overall scores. The superior performance of SAINT is attributed to its dual attention mechanism, which effectively models feature interactions within and across samples. These findings demonstrate the diagnostic potential of attention-based deep learning architectures for early Parkinson’s disease detection and highlight the importance of dynamic feature representation in clinical prediction tasks.
[825] A Thermodynamic Theory of Learning Part II: Critical Period Closure and Continual Learning Failure
Daisuke Okanohara
Main category: cs.LG
TL;DR: Finite-time learning is irreversible, causing critical period closure where transitions between compatible representations become inaccessible, reframing catastrophic forgetting as a dynamical constraint rather than task interference.
Details
Motivation: The paper aims to understand how irreversibility in finite-time learning affects continual learning, specifically why catastrophic forgetting occurs despite the existence of solutions that satisfy multiple tasks.Method: The authors study continual learning from a trajectory-level perspective using transport process modeling in parameter space, analyzing how finite dissipation constrains learning paths and dynamically accessible solutions.
Result: Finite-time learning irreversibly selects among task-equivalent realizations through progressive elimination of degrees of freedom, leading to critical period closure where transitions between compatible representations become inaccessible.
Conclusion: Catastrophic forgetting arises from irreversible loss of representational freedom induced by prior learning, framed as a dynamical constraint imposed by finite-time dissipation rather than direct task interference.
Abstract: Learning performed over finite time is necessarily irreversible. In PartI of this series, we modeled learning as a transport process in the space of parameter distributions and derived the Epistemic Speed Limit, which lower-bounds entropy production under finite-time learning.
In this work (PartII), we study the consequences of this irreversibility for continual learning from a trajectory-level perspective. We show that finite dissipation constrains not only which solutions are reachable, but which learning paths remain dynamically accessible.
Although a continuum of task-equivalent realizations can achieve identical task performance, finite-time learning irreversibly selects among these realizations. This selection occurs through the progressive elimination of degrees of freedom that would otherwise enable structural reconfiguration. We refer to this phenomenon as \emph{critical period closure}: beyond a certain stage of learning, transitions between compatible representations become dynamically inaccessible under any finite dissipation budget.
As a result, continual learning failure arises not from the absence of solutions satisfying multiple tasks, but from an irreversible loss of representational freedom induced by prior learning. This reframes catastrophic forgetting as a dynamical constraint imposed by finite-time dissipation, rather than direct task interference.
[826] An Explainable Multi-Task Similarity Measure: Integrating Accumulated Local Effects and Weighted Fréchet Distance
Pablo Hidalgo, Daniel Rodriguez
Main category: cs.LG
TL;DR: Proposes an explainable AI-based similarity measure for multi-task learning using ALE curves and Fréchet distance to quantify task relationships
Details
Motivation: Multi-task learning requires understanding which tasks are similar and why, but existing approaches lack explainable similarity measures that can work across different models and data typesMethod: Uses Accumulated Local Effects (ALE) curves from XAI to capture feature importance patterns, compares them using weighted Fréchet distance, incorporates scaling for performance differences, and is model-agnostic
Result: Validated on synthetic, Parkinson’s, bike-sharing, and CelebA datasets; measure aligns with intuitive task similarity expectations across tabular and non-tabular data
Conclusion: Provides an explainable, model-agnostic similarity measure for multi-task learning that helps explore task relationships and supports informed decision-making
Abstract: In many machine learning contexts, tasks are often treated as interconnected components with the goal of leveraging knowledge transfer between them, which is the central aim of Multi-Task Learning (MTL). Consequently, this multi-task scenario requires addressing critical questions: which tasks are similar, and how and why do they exhibit similarity? In this work, we propose a multi-task similarity measure based on Explainable Artificial Intelligence (XAI) techniques, specifically Accumulated Local Effects (ALE) curves. ALE curves are compared using the Fréchet distance, weighted by the data distribution, and the resulting similarity measure incorporates the importance of each feature. The measure is applicable in both single-task learning scenarios, where each task is trained separately, and multi-task learning scenarios, where all tasks are learned simultaneously. The measure is model-agnostic, allowing the use of different machine learning models across tasks. A scaling factor is introduced to account for differences in predictive performance across tasks, and several recommendations are provided for applying the measure in complex scenarios. We validate this measure using four datasets, one synthetic dataset and three real-world datasets. The real-world datasets include a well-known Parkinson’s dataset and a bike-sharing usage dataset – both structured in tabular format – as well as the CelebA dataset, which is used to evaluate the application of concept bottleneck encoders in a multitask learning setting. The results demonstrate that the measure aligns with intuitive expectations of task similarity across both tabular and non-tabular data, making it a valuable tool for exploring relationships between tasks and supporting informed decision-making.
[827] ManifoldKV: Training-Free KV Cache Compression via Euclidean Outlier Detection
Debajyoti Datta, Trishala Neeraj, Bibek Paudel, Vyom Sharma, Subhabrata Mukherjee
Main category: cs.LG
TL;DR: ManifoldKV is a training-free KV-cache compression method that uses Euclidean distance instead of cosine similarity to select which past tokens to retain, improving robustness in long-context inference.
Details
Motivation: KV-cache memory grows linearly with sequence length in long-context inference, requiring compression. Existing geometry-based eviction methods use cosine similarity which discards magnitude cues that distinguish semantically salient tokens.Method: Proposes ManifoldKV which ranks tokens by Euclidean distance to the key centroid (capturing both angular and radial deviations). Also introduces WindowedManifoldKV for very long contexts (64K+) to address centroid dilution issues.
Result: Achieves 95.7% accuracy at 4K-16K contexts with 20% compression; improves multi-key retrieval by 15.4 points; WindowedManifoldKV restores accuracy to 84.3% at 25% compression for 64K contexts (49-point recovery).
Conclusion: ManifoldKV provides a simple, effective KV-cache compression method that works across multiple architectures without tuning, addressing limitations of cosine-based scoring.
Abstract: Long-context inference is constrained by KV-cache memory, which grows linearly with sequence length; KV-cache compression therefore hinges on reliably selecting which past tokens to retain. Most geometry-based eviction methods score keys by cosine similarity to a global centroid, but cosine is scale-invariant and can discard magnitude cues that distinguish semantically salient tokens. We propose ManifoldKV, a training-free scorer that ranks tokens by Euclidean distance to the key centroid, capturing both angular and radial deviations. On the RULER benchmark, ManifoldKV achieves 95.7% accuracy at 4K-16K contexts with 20% compression; matching the best geometric baseline while improving robustness in two regimes where cosine scoring fails. First, on multi-key retrieval, ManifoldKV reduces directional collisions, achieving 92.4% vs KeyDiff’s 77.0% (+15.4 points) on 3-key NIAH at 50% compression. Second, to address dilution and performance collapse of global centroids at 64K context, we introduce WindowedManifoldKV, which restores accuracy to 84.3% at 25% compression, a 49-point recovery over global L2 and +3.2 points over KeyDiff. The method requires only 3 lines of code and works across 4 architectures without tuning.
[828] On Improving Neurosymbolic Learning by Exploiting the Representation Space
Aaditya Naik, Efthymia Tsamoura, Shibo Jin, Mayur Naik, Dan Roth
Main category: cs.LG
TL;DR: CLIPPER is a pruning technique for neurosymbolic learning that reduces the exponential space of label combinations by exploiting similarity in latent representations while respecting logical constraints.
Details
Motivation: Neurosymbolic learning with logical constraints faces computational challenges due to exponential growth in possible label combinations that satisfy logical formulas, making training difficult.Method: Proposes CLIPPER which prunes inconsistent label combinations using an integer linear program that leverages the intuition that similar latent representations should share labels while respecting logical dependencies.
Result: CLIPPER boosts performance of state-of-the-art neurosymbolic engines (Scallop, Dolphin, ISED) by up to 48%, 53%, and 8% respectively across 16 benchmarks, achieving state-of-the-art accuracies.
Conclusion: The approach effectively addresses computational challenges in neurosymbolic learning and can be seamlessly integrated with existing training algorithms to improve performance on complex neurosymbolic tasks.
Abstract: We study the problem of learning neural classifiers in a neurosymbolic setting where the hidden gold labels of input instances must satisfy a logical formula. Learning in this setting proceeds by first computing (a subset of) the possible combinations of labels that satisfy the formula and then computing a loss using those combinations and the classifiers’ scores. One challenge is that the space of label combinations can grow exponentially, making learning difficult. We propose a technique that prunes this space by exploiting the intuition that instances with similar latent representations are likely to share the same label. While this intuition has been widely used in weakly supervised learning, its application in our setting is challenging due to label dependencies imposed by logical constraints. We formulate the pruning process as an integer linear program that discards inconsistent label combinations while respecting logical structure. Our approach, CLIPPER, is orthogonal to existing training algorithms and can be seamlessly integrated with them. Across 16 benchmarks over complex neurosymbolic tasks, we demonstrate that CLIPPER boosts the performance of state-of-the-art neurosymbolic engines like Scallop, Dolphin, and ISED by up to 48%, 53%, and 8%, leading to state-of-the-art accuracies.
[829] Reinforcement Learning with Backtracking Feedback
Bilgehan Sel, Vaishakh Keshava, Phillip Wallis, Lukas Rutishauser, Ming Jin, Dingcheng Li
Main category: cs.LG
TL;DR: RLBF is a reinforcement learning framework that trains LLMs to self-correct safety violations by learning to backtrack and regenerate text when detecting errors, improving robustness against adversarial attacks while preserving model utility.
Details
Motivation: Addressing the critical need for robust safety in LLMs against adversarial attacks and in-distribution errors, as current methods lack dynamic self-correction capabilities during generation.Method: Uses RL with critic feedback where models learn to emit “backtrack by x tokens” signals to correct live generation errors, plus enhanced SFT data generation (BSAFE+) that injects violations into safe text for better initial training.
Result: Significantly reduces attack success rates across diverse benchmarks and model scales, achieving superior safety outcomes while preserving foundational model utility.
Conclusion: RLBF provides an effective framework for making LLMs more resilient to sophisticated adversarial attacks through dynamic self-correction mechanisms during generation.
Abstract: Addressing the critical need for robust safety in Large Language Models (LLMs), particularly against adversarial attacks and in-distribution errors, we introduce Reinforcement Learning with Backtracking Feedback (RLBF). This framework advances upon prior methods, such as BSAFE, by primarily leveraging a Reinforcement Learning (RL) stage where models learn to dynamically correct their own generation errors. Through RL with critic feedback on the model’s live outputs, LLMs are trained to identify and recover from their actual, emergent safety violations by emitting an efficient “backtrack by x tokens” signal, then continuing generation autoregressively. This RL process is crucial for instilling resilience against sophisticated adversarial strategies, including middle filling, Greedy Coordinate Gradient (GCG) attacks, and decoding parameter manipulations. To further support the acquisition of this backtracking capability, we also propose an enhanced Supervised Fine-Tuning (SFT) data generation strategy (BSAFE+). This method improves upon previous data creation techniques by injecting violations into coherent, originally safe text, providing more effective initial training for the backtracking mechanism. Comprehensive empirical evaluations demonstrate that RLBF significantly reduces attack success rates across diverse benchmarks and model scales, achieving superior safety outcomes while critically preserving foundational model utility.
[830] Beyond Optimization: Intelligence as Metric-Topology Factorization under Geometric Incompleteness
Xin Li
Main category: cs.LG
TL;DR: MTF proposes intelligence as reshaping representational geometry rather than optimization in fixed spaces, factorizing stable topology from plastic metric warps to handle distributional shifts and prevent catastrophic forgetting.
Details
Motivation: Current ML approaches treat intelligence as optimization within fixed geometric representations, which fails under distributional shift, task permutation, and continual learning due to catastrophic forgetting when topological changes occur.Method: Metric-Topology Factorization (MTF) separates stable topological structure from plastic metric deformations. The Topological Urysohn Machine (TUM) implements MTF through memory-amortized metric inference (MAMI) where spectral task signatures index amortized metric transformations.
Result: MTF enables rapid adaptation via geometric switching rather than re-optimization, providing robustness to task reordering, resistance to catastrophic forgetting, and generalization across transformations that defeat conventional continual learning methods.
Conclusion: Intelligence should be viewed as the ability to reshape representational geometry rather than navigation through fixed spaces, with MTF providing a principled geometric framework for handling distributional shifts and continual learning challenges.
Abstract: Contemporary ML often equates intelligence with optimization: searching for solutions within a fixed representational geometry. This works in static regimes but breaks under distributional shift, task permutation, and continual learning, where even mild topological changes can invalidate learned solutions and trigger catastrophic forgetting. We propose Metric-Topology Factorization (MTF) as a unifying geometric principle: intelligence is not navigation through a fixed maze, but the ability to reshape representational geometry so desired behaviors become stable attractors. Learning corresponds to metric contraction (a controlled deformation of Riemannian structure), while task identity and environmental variation are encoded topologically and stored separately in memory. We show any fixed metric is geometrically incomplete: for any local metric representation, some topological transformations make it singular or incoherent, implying an unavoidable stability-plasticity tradeoff for weight-based systems. MTF resolves this by factorizing stable topology from plastic metric warps, enabling rapid adaptation via geometric switching rather than re-optimization. Building on this, we introduce the Topological Urysohn Machine (TUM), implementing MTF through memory-amortized metric inference (MAMI): spectral task signatures index amortized metric transformations, letting a single learned geometry be reused across permuted, reflected, or parity-altered environments. This explains robustness to task reordering, resistance to catastrophic forgetting, and generalization across transformations that defeat conventional continual learning methods (e.g., EWC).
[831] Beyond Correctness: Learning Robust Reasoning via Transfer
Hyunseok Lee, Soheil Abbasloo, Jihoon Tack, Jinwoo Shin
Main category: cs.LG
TL;DR: RLTR introduces transfer rewards to make LLM reasoning robust beyond just final answer correctness, ensuring reasoning remains useful when transferred between models
Details
Motivation: Current RLVR focuses only on final answer correctness but doesn't ensure robustness of the reasoning process itself. Reasoning should remain useful beyond the model that produced it and survive truncation, reinterpretation, and continuation.Method: Introduces Reinforcement Learning with Transferable Reward (RLTR) which operationalizes robustness via transfer reward that tests whether a partial reasoning prefix from one model can guide a separate model to the correct answer.
Result: Improves sampling consistency while improving final answer accuracy, achieves +3.6%p gain in Maj@64 on MATH500 compared to RLVR, matches RLVR’s average accuracy with roughly 2.5x fewer training steps.
Conclusion: RLTR provides more reliable reasoning and significantly more sample efficiency by encouraging LLMs to produce reasoning that is stable, interpretable, and genuinely generalizable.
Abstract: Reinforcement Learning with Verifiable Rewards (RLVR) has recently strengthened LLM reasoning, but its focus on final answer correctness leaves a critical gap: it does not ensure the robustness of the reasoning process itself. We adopt a simple philosophical view, robust reasoning should remain useful beyond the mind that produced it, and treat reasoning as a form of meaning transfer that must survive truncation, reinterpretation, and continuation. Building on this principle, we introduce Reinforcement Learning with Transferable Reward (RLTR), which operationalizes robustness via transfer reward that tests whether a partial reasoning prefix from one model can guide a separate model to the correct answer. This encourages LLMs to produce reasoning that is stable, interpretable, and genuinely generalizable. Our approach improves sampling consistency while improving final answer accuracy, and it reaches comparable performance in substantially fewer training steps. For example, on MATH500, RLTR achieves a +3.6%p gain in Maj@64 compared to RLVR and matches RLVR’s average accuracy with roughly 2.5x fewer training steps, providing both more reliable reasoning and significantly more sample efficient.
[832] When Is Compositional Reasoning Learnable from Verifiable Rewards?
Daniel Barzilai, Yotam Wolf, Ronen Basri
Main category: cs.LG
TL;DR: Theoretical analysis of compositional reasoning learnability in autoregressive models under RLVR training, identifying task-advantage ratio as key determinant of learnability from outcome-level feedback.
Details
Motivation: Despite empirical successes of RLVR in enabling compositional reasoning in LLMs, it remains unclear which compositional problems are learnable using only outcome-level feedback, motivating theoretical analysis of learnability conditions.Method: Theoretical study of compositional problems in autoregressive models under RLVR training, identifying and analyzing the task-advantage ratio - a joint property of compositional problems and base models that characterizes learnability.
Result: Shows that compositional problems where correct intermediate steps provide clear advantage are efficiently learnable with RLVR, while problems lacking structural advantage may converge to suboptimal compositions; base model quality can determine existence of advantage.
Conclusion: Provides principled theoretical understanding of when RLVR succeeds or fails for compositional reasoning, with task-advantage ratio as key theoretical construct for analyzing learnability from outcome-level feedback.
Abstract: The emergence of compositional reasoning in large language models through reinforcement learning with verifiable rewards (RLVR) has been a key driver of recent empirical successes. Despite this progress, it remains unclear which compositional problems are learnable in this setting using outcome-level feedback alone. In this work, we theoretically study the learnability of compositional problems in autoregressive models under RLVR training. We identify a quantity that we call the task-advantage ratio, a joint property of the compositional problem and the base model, that characterizes which tasks and compositions are learnable from outcome-level feedback. On the positive side, using this characterization, we show that compositional problems where correct intermediate steps provide a clear advantage are efficiently learnable with RLVR. We also analyze how such an advantage naturally arises in different problems. On the negative side, when the structural advantage is not present, RLVR may converge to suboptimal compositions. We prove that, in some cases, the quality of the base model determines if such an advantage exists and whether RLVR will converge to a suboptimal solution. We hope our analysis can provide a principled theoretical understanding of when and why RLVR succeeds and when it does not.
[833] Regret Analysis of Unichain Average Reward Constrained MDPs with General Parameterization
Anirudh Satheesh, Vaneet Aggarwal
Main category: cs.LG
TL;DR: A primal-dual natural actor-critic algorithm for constrained MDPs with unichain dynamics using multi-level Monte Carlo estimators and burn-in mechanism achieves optimal regret bounds without mixing-time assumptions.
Details
Motivation: Existing constrained RL analyses rely on ergodicity or strong mixing-time assumptions that fail for systems with transient states. There's a need for algorithms that work under more general unichain dynamics without requiring mixing-time oracles.Method: Proposes a primal-dual natural actor-critic algorithm that uses multi-level Monte Carlo (MLMC) estimators and an explicit burn-in mechanism to handle unichain dynamics. The approach avoids mixing-time oracles while maintaining theoretical guarantees.
Result: Achieves finite-time regret and cumulative constraint violation bounds scaling as $\tilde{O}(\sqrt{T})$, up to approximation errors from policy and critic parameterization. Extends order-optimal guarantees to broader class of CMDPs with unichain dynamics.
Conclusion: The algorithm successfully handles constrained MDPs with unichain dynamics without requiring mixing-time assumptions, providing optimal regret guarantees for a significantly broader class of problems than previous methods.
Abstract: We study infinite-horizon average-reward constrained Markov decision processes (CMDPs) under the unichain assumption and general policy parameterizations. Existing regret analyses for constrained reinforcement learning largely rely on ergodicity or strong mixing-time assumptions, which fail to hold in the presence of transient states. We propose a primal–dual natural actor–critic algorithm that leverages multi-level Monte Carlo (MLMC) estimators and an explicit burn-in mechanism to handle unichain dynamics without requiring mixing-time oracles. Our analysis establishes finite-time regret and cumulative constraint violation bounds that scale as $\tilde{O}(\sqrt{T})$, up to approximation errors arising from policy and critic parameterization, thereby extending order-optimal guarantees to a significantly broader class of CMDPs.
[834] Don’t Always Pick the Highest-Performing Model: An Information Theoretic View of LLM Ensemble Selection
Yigit Turkmen, Baturalp Buyukates, Melih Bastopcu
Main category: cs.LG
TL;DR: Proposes a greedy mutual-information selection algorithm for budgeted LLM ensemble selection that outperforms baselines on QA and sentiment classification tasks.
Details
Motivation: LLM ensembles often show strong correlations, raising the question of which models to select for optimal ensemble performance under query budget constraints.Method: Formulates ensemble selection as maximizing mutual information between true labels and predictions, models correlated errors with Gaussian-copula, and proposes greedy mutual-information selection algorithm that estimates information terms from data.
Result: Method consistently outperforms strong baselines under same query budget across MEDMCQA, MMLU (QA datasets), and IMDB sentiment classification datasets.
Conclusion: The proposed greedy mutual-information selection algorithm effectively builds LLM ensembles under budget constraints by addressing model correlation issues.
Abstract: Large language models (LLMs) are often ensembled together to improve overall reliability and robustness, but in practice models are strongly correlated. This raises a fundamental question: which models should be selected when forming an LLM ensemble? We formulate budgeted ensemble selection as maximizing the mutual information between the true label and predictions of the selected models. Furthermore, to explain why performance can saturate even with many models, we model the correlated errors of the models using Gaussian-copula and show an information-theoretic error floor for the performance of the ensemble. Motivated by these, we propose a simple greedy mutual-information selection algorithm that estimates the required information terms directly from data and iteratively builds an ensemble under a query budget. We test our approach in two question answering datasets and one binary sentiment classification dataset: MEDMCQA, MMLU, and IMDB movie reviews. Across all datasets, we observe that our method consistently outperforms strong baselines under the same query budget.
[835] From $O(mn)$ to $O(r^2)$: Two-Sided Low-Rank Communication for Adam in Distributed Training with Memory Efficiency
Sizhe Dang, Jiaqi Shao, Xiaodong Zheng, Guang Dai, Yan Song, Haishan Ye
Main category: cs.LG
TL;DR: TSR-Adam reduces communication overhead in distributed training by using two-sided low-rank gradient synchronization with randomized SVD refresh, achieving 13-25× communication reduction while maintaining performance.
Details
Motivation: As foundation models scale, pretraining relies on data-parallel distributed optimization where bandwidth-limited gradient synchronization becomes a key bottleneck. Existing projection-based low-rank optimizers are suboptimal for communication-limited training due to one-sided synchronization and refresh steps that dominate communication.Method: Proposes TSR-Adam which brings two-sided low-rank communication to Adam-family updates by synchronizing a compact core U⊤GV ∈ ℝ^{r×r}, reducing payload from O(mn) to O(r²). Uses randomized SVD-based refresh to avoid full-gradient synchronization. Extends to embedding gradients with embedding-specific ranks and refresh schedules.
Result: Across pretraining from 60M to 1B model scales, TSR-Adam reduces average communicated bytes per step by 13×, and on GLUE fine-tuning reduces communication by 25×, while achieving comparable performance to standard Adam.
Conclusion: TSR-Adam effectively addresses communication bottlenecks in distributed training of large models through efficient low-rank gradient synchronization, enabling significant bandwidth savings without compromising model performance.
Abstract: As foundation models continue to scale, pretraining increasingly relies on data-parallel distributed optimization, making bandwidth-limited gradient synchronization a key bottleneck. Orthogonally, projection-based low-rank optimizers were mainly designed for memory efficiency, but remain suboptimal for communication-limited training: one-sided synchronization still transmits an $O(rn)$ object for an $m\times n$ matrix gradient and refresh steps can dominate peak communicated bytes. We propose TSR, which brings two-sided low-rank communication to Adam-family updates (TSR-Adam) by synchronizing a compact core $U^\top G V\in\mathbb{R}^{r\times r}$, reducing the dominant per-step payload from $O(mn)$ to $O(r^2)$ while keeping moment states in low-dimensional cores. To further reduce the peak communication from subspace refresh, TSR-Adam adopts a randomized SVD-based refresh that avoids full-gradient synchronization. We additionally extend low-rank communication to embedding gradients with embedding-specific ranks and refresh schedules, yielding additional communication and memory savings over keeping embeddings dense. Across pretraining from 60M to 1B model scales, TSR-Adam reduces average communicated bytes per step by $13\times$, and on GLUE fine-tuning it reduces communication by $25\times$, while achieving comparable performance; we further provide a theoretical stationarity analysis for the proposed update. Code is available at https://github.com/DKmiyan/TSR-Adam.
[836] Bayesian Preference Learning for Test-Time Steerable Reward Models
Jiwoo Hong, Shao Tang, Zhipeng Wang
Main category: cs.LG
TL;DR: ICRM enables test-time steerable reward models via in-context preference demonstrations using Bayesian variational inference, improving adaptability to unseen preference distributions.
Details
Motivation: Current reward models are static after training, limiting adaptability to complex, multifaceted preference distributions needed for verifiable rewards and multi-objective alignment in RL settings.Method: Proposes Variational In-Context Reward Modeling (ICRM) using amortized variational inference over latent preference probabilities under Bradley-Terry model with Beta conjugate prior, enabling test-time adaptation via in-context demonstrations.
Result: ICRM gains 34% accuracy on SafeRLHF and 9% on RM-Bench in single-objective settings, widens Pareto frontier with 4% hypervolume gain on helpfulness/refusal benchmarks, and outperforms conventional RMs in math reasoning for verifiable rewards.
Conclusion: ICRM provides a flexible, test-time steerable reward modeling framework that adapts to unseen preference distributions with theoretical guarantees on optimization and regularization against reward over-optimization.
Abstract: Reward models are central to aligning language models with human preferences via reinforcement learning (RL). As RL is increasingly applied to settings such as verifiable rewards and multi-objective alignment, RMs are expected to encode more complex and multifaceted preference distributions. However, classifier RMs remain static once trained, limiting their adaptability at test time. We propose Variational In-Context Reward Modeling (ICRM), a novel Bayesian reward modeling objective that enables test-time steerability via in-context preference demonstrations. ICRM casts reward modeling as amortized variational inference over a latent preference probability under the Bradley-Terry model using a conjugate Beta prior. We show that ICRM adapt to unseen preference distributions at test time for both single and multi-objective settings. With more in-context demonstrations, ICRM gains 34% accuracy on SafeRLHF and 9% accuracy on RM-Bench in the single-objective setting, while widening the Pareto frontier with a 4% gain in hypervolume on helpfulness and refusal benchmarks. We further study the practical applicability of ICRM for RL training, showing that it can effectively encode verifiable rewards by outperforming a conventional RM in math reasoning. Finally, we provide theoretical guarantees that the variational objective admits a global interior optimum with finite confidence, and we analyze how KL regularization mitigates reward over-optimization.
[837] A Unified Density Operator View of Flow Control and Merging
Riccardo De Santi, Malte Franke, Ya-Ping Hsieh, Andreas Krause
Main category: cs.LG
TL;DR: A unified probability-space framework for reward-guided flow merging that enables principled combination of multiple pre-trained generative models with theoretical guarantees.
Details
Motivation: Address two fundamental challenges in large-scale flow and diffusion models: (1) control-based reward adaptation of pre-trained flows, and (2) integration of multiple models (flow merging). Current approaches address these separately, creating a need for a unifying framework.Method: Introduces a probability-space framework that subsumes both reward adaptation and flow merging as limit cases. Proposes Reward-Guided Flow Merging (RFM) using mirror-descent scheme that reduces the problem to a sequence of standard fine-tuning problems. Enables various operators over generative model densities including intersection, union, interpolation, and complex logical expressions via generative circuits.
Result: Provides first-of-their-kind theoretical guarantees for reward-guided and pure flow merging via RFM. Demonstrates capabilities on illustrative settings with visually interpretable insights, and applies to high-dimensional de-novo molecular design and low-energy conformer generation.
Conclusion: The proposed framework unifies reward adaptation and flow merging, enabling principled, task-aware combination of multiple pre-trained flows with theoretical guarantees, demonstrated on practical applications including molecular design.
Abstract: Recent progress in large-scale flow and diffusion models raised two fundamental algorithmic challenges: (i) control-based reward adaptation of pre-trained flows, and (ii) integration of multiple models, i.e., flow merging. While current approaches address them separately, we introduce a unifying probability-space framework that subsumes both as limit cases, and enables reward-guided flow merging, allowing principled, task-aware combination of multiple pre-trained flows (e.g., merging priors while maximizing drug-discovery utilities). Our formulation renders possible to express a rich family of operators over generative models densities, including intersection (e.g., to enforce safety), union (e.g., to compose diverse models), interpolation (e.g., for discovery), their reward-guided counterparts, as well as complex logical expressions via generative circuits. Next, we introduce Reward-Guided Flow Merging (RFM), a mirror-descent scheme that reduces reward-guided flow merging to a sequence of standard fine-tuning problems. Then, we provide first-of-their-kind theoretical guarantees for reward-guided and pure flow merging via RFM. Ultimately, we showcase the capabilities of the proposed method on illustrative settings providing visually interpretable insights, and apply our method to high-dimensional de-novo molecular design and low-energy conformer generation.
[838] Discovering Interpretable Algorithms by Decompiling Transformers to RASP
Xinting Huang, Aleksandra Bakalova, Satwik Bhattamishra, William Merrill, Michael Hahn
Main category: cs.LG
TL;DR: Method to extract interpretable RASP programs from trained Transformers by re-parameterizing them as RASP programs and applying causal interventions to find minimal sufficient sub-programs.
Details
Motivation: While Transformers have been shown to simulate RASP programs and length-generalize on problems with simple RASP implementations, it remains unclear whether trained models actually implement such interpretable programs internally.Method: Faithfully re-parameterize a Transformer as a RASP program, then apply causal interventions to discover a small sufficient sub-program that captures the model’s essential computations.
Result: On small Transformers trained on algorithmic and formal language tasks, the method often recovers simple and interpretable RASP programs from length-generalizing transformers.
Conclusion: Provides direct evidence that Transformers internally implement simple RASP programs, advancing understanding of Transformer interpretability and generalization mechanisms.
Abstract: Recent work has shown that the computations of Transformers can be simulated in the RASP family of programming languages. These findings have enabled improved understanding of the expressive capacity and generalization abilities of Transformers. In particular, Transformers have been suggested to length-generalize exactly on problems that have simple RASP programs. However, it remains open whether trained models actually implement simple interpretable programs. In this paper, we present a general method to extract such programs from trained Transformers. The idea is to faithfully re-parameterize a Transformer as a RASP program and then apply causal interventions to discover a small sufficient sub-program. In experiments on small Transformers trained on algorithmic and formal language tasks, we show that our method often recovers simple and interpretable RASP programs from length-generalizing transformers. Our results provide the most direct evidence so far that Transformers internally implement simple RASP programs.
[839] The Rise of Sparse Mixture-of-Experts: A Survey from Algorithmic Foundations to Decentralized Architectures and Vertical Domain Applications
Dong Pan, Bingtao Li, Yongsheng Zheng, Jiren Ma, Victor Fei
Main category: cs.LG
TL;DR: A comprehensive survey on sparse Mixture of Experts (MoE) architecture covering foundational principles, routing/expert networks, decentralized paradigms, vertical applications, and future research directions.
Details
Motivation: Despite growing popularity of MoE models across various domains, there's a lack of systematic exploration of recent advancements. Existing surveys have limitations in coverage and depth, particularly in key areas like decentralized paradigms and vertical applications.Method: Survey methodology examining: 1) foundational principles of MoE with focus on routing and expert networks, 2) extension from centralized to decentralized paradigms, 3) vertical domain applications, and 4) identification of key challenges and future directions.
Result: Presents the most comprehensive review in MoE field to date, covering both technical foundations and practical applications across various domains.
Conclusion: This survey fills existing gaps in MoE literature and serves as a valuable resource for researchers and practitioners to navigate latest advancements in the field.
Abstract: The sparse Mixture of Experts(MoE) architecture has evolved as a powerful approach for scaling deep learning models to more parameters with comparable computation cost. As an important branch of large language model(LLM), MoE model only activate a subset of experts based on a routing network. This sparse conditional computation mechanism significantly improves computational efficiency, paving a promising path for greater scalability and cost-efficiency. It not only enhance downstream applications such as natural language processing, computer vision, and multimodal in various horizontal domains, but also exhibit broad applicability across vertical domains. Despite the growing popularity and application of MoE models across various domains, there lacks a systematic exploration of recent advancements of MoE in many important fields. Existing surveys on MoE suffer from limitations such as lack coverage or none extensively exploration of key areas. This survey seeks to fill these gaps. In this paper, Firstly, we examine the foundational principles of MoE, with an in-depth exploration of its core components-the routing network and expert network. Subsequently, we extend beyond the centralized paradigm to the decentralized paradigm, which unlocks the immense untapped potential of decentralized infrastructure, enables democratization of MoE development for broader communities, and delivers greater scalability and cost-efficiency. Furthermore we focus on exploring its vertical domain applications. Finally, we also identify key challenges and promising future research directions. To the best of our knowledge, this survey is currently the most comprehensive review in the field of MoE. We aim for this article to serve as a valuable resource for both researchers and practitioners, enabling them to navigate and stay up-to-date with the latest advancements.
[840] A Behavioural and Representational Evaluation of Goal-Directedness in Language Model Agents
Raghu Arghal, Fade Chen, Niall Dalton, Evgenii Kortukov, Calum McNamara, Angelos Nalmpantis, Moksh Nirvaan, Gabriele Sarti, Mario Giulianelli
Main category: cs.LG
TL;DR: A framework for evaluating goal-directedness in AI agents combining behavioral analysis with interpretability methods, applied to an LLM agent navigating a 2D grid world.
Details
Motivation: There's no established methodology for reliably attributing goals to agentic systems, and understanding an agent's goals is crucial for explaining and predicting its behavior.Method: Integrated behavioral evaluation with interpretability-based analysis of internal representations. Used an LLM agent navigating a 2D grid world, evaluated against optimal policy across varying grid sizes, obstacle densities, and goal structures. Applied probing methods to decode the agent’s internal representations of environment state and multi-step action plans.
Result: Performance scales with task difficulty while remaining robust to difficulty-preserving transformations and complex goal structures. The LLM agent non-linearly encodes a coarse spatial map, preserving approximate task-relevant cues about position and goal location. Actions are consistent with internal representations, and reasoning reorganizes representations from broader structural cues toward immediate action selection.
Conclusion: Introspective examination beyond behavioral evaluations is required to characterize how agents represent and pursue objectives, supporting the need for integrated evaluation frameworks.
Abstract: Understanding an agent’s goals helps explain and predict its behaviour, yet there is no established methodology for reliably attributing goals to agentic systems. We propose a framework for evaluating goal-directedness that integrates behavioural evaluation with interpretability-based analyses of models’ internal representations. As a case study, we examine an LLM agent navigating a 2D grid world toward a goal state. Behaviourally, we evaluate the agent against an optimal policy across varying grid sizes, obstacle densities, and goal structures, finding that performance scales with task difficulty while remaining robust to difficulty-preserving transformations and complex goal structures. We then use probing methods to decode the agent’s internal representations of the environment state and its multi-step action plans. We find that the LLM agent non-linearly encodes a coarse spatial map of the environment, preserving approximate task-relevant cues about its position and the goal location; that its actions are broadly consistent with these internal representations; and that reasoning reorganises them, shifting from broader environment structural cues toward information supporting immediate action selection. Our findings support the view that introspective examination is required beyond behavioural evaluations to characterise how agents represent and pursue their objectives.
[841] Sharp analysis of linear ensemble sampling
Arya Akhavan, David Janz, Csaba Szepesvári
Main category: cs.LG
TL;DR: Analysis of linear ensemble sampling with Gaussian perturbations in stochastic linear bandits, showing that with ensemble size m=Θ(d log n), ES achieves near-optimal regret comparable to Thompson sampling while maintaining computational efficiency.
Details
Motivation: The paper aims to bridge the gap between Thompson sampling and ensemble sampling in linear bandits, seeking to achieve comparable regret performance while keeping computational costs manageable. Ensemble sampling offers computational advantages but previously had theoretical gaps compared to Thompson sampling.Method: The authors analyze linear ensemble sampling with standard Gaussian perturbations using a novel continuous-time approach. They reduce the analysis to a time-uniform exceedance problem for m independent Brownian motions, providing a new perspective on randomized exploration in linear bandits.
Result: For ensemble size m=Θ(d log n), ES attains $\tilde O(d^{3/2}\sqrt n)$ high-probability regret, closing the theoretical gap to the Thompson sampling benchmark while maintaining comparable computational efficiency.
Conclusion: The continuous-time approach appears natural and perhaps necessary for obtaining sharp bounds on ensemble sampling in linear bandits, providing a new analytical framework for understanding randomized exploration strategies.
Abstract: We analyse linear ensemble sampling (ES) with standard Gaussian perturbations in stochastic linear bandits. We show that for ensemble size $m=Θ(d\log n)$, ES attains $\tilde O(d^{3/2}\sqrt n)$ high-probability regret, closing the gap to the Thompson sampling benchmark while keeping computation comparable. The proof brings a new perspective on randomized exploration in linear bandits by reducing the analysis to a time-uniform exceedance problem for $m$ independent Brownian motions. Intriguingly, this continuous-time lens is not forced; it appears natural–and perhaps necessary: the discrete-time problem seems to be asking for a continuous-time solution, and we know of no other way to obtain a sharp ES bound.
[842] Horizon Imagination: Efficient On-Policy Training in Diffusion World Models
Lior Cohen, Ofir Nabati, Kaixin Wang, Navdeep Kumar, Shie Mannor
Main category: cs.LG
TL;DR: Horizon Imagination (HI) is an efficient diffusion-based world model for RL that enables parallel denoising of future observations with sub-frame budgets, improving computational efficiency while maintaining control performance.
Details
Motivation: Current diffusion-based world models for reinforcement learning face efficiency challenges - they either require heavyweight models at inference or rely on highly sequential imagination processes, both imposing prohibitive computational costs that limit practical applications.Method: Proposes Horizon Imagination (HI), an on-policy imagination process for discrete stochastic policies that denoises multiple future observations in parallel. Includes a stabilization mechanism and novel sampling schedule that decouples denoising budget from effective horizon while supporting sub-frame budgets.
Result: Experiments on Atari 100K and Craftium show HI maintains control performance with half the denoising steps (sub-frame budget) and achieves superior generation quality under varied sampling schedules compared to existing methods.
Conclusion: HI provides an efficient solution for diffusion-based world models in RL, enabling parallel imagination with reduced computational costs while preserving control performance, making diffusion models more practical for reinforcement learning applications.
Abstract: We study diffusion-based world models for reinforcement learning, which offer high generative fidelity but face critical efficiency challenges in control. Current methods either require heavyweight models at inference or rely on highly sequential imagination, both of which impose prohibitive computational costs. We propose Horizon Imagination (HI), an on-policy imagination process for discrete stochastic policies that denoises multiple future observations in parallel. HI incorporates a stabilization mechanism and a novel sampling schedule that decouples the denoising budget from the effective horizon over which denoising is applied while also supporting sub-frame budgets. Experiments on Atari 100K and Craftium show that our approach maintains control performance with a sub-frame budget of half the denoising steps and achieves superior generation quality under varied schedules. Code is available at https://github.com/leor-c/horizon-imagination.
[843] Next-Gen CAPTCHAs: Leveraging the Cognitive Gap for Scalable and Diverse GUI-Agent Defense
Jiacheng Liu, Yaxin Luo, Jiacheng Cui, Xinyi Shang, Xiaohan Zhao, Zhiqiang Shen
Main category: cs.LG
TL;DR: Next-Gen CAPTCHAs framework uses dynamic tasks exploiting human-agent cognitive gaps in interactive perception, memory, decision-making, and action to create scalable security against advanced multimodal agents.
Details
Motivation: Traditional CAPTCHAs are obsolete due to advanced multimodal agents achieving 90% pass rates on complex logic puzzles. Need new security framework for agentic era that distinguishes biological users from artificial agents.Method: Built scalable benchmark with robust data generation pipeline for large-scale evaluation. Engineered dynamic tasks requiring adaptive intuition rather than granular planning, exploiting persistent human-agent cognitive gaps in interactive perception, memory, decision-making, and action.
Result: Framework enables generation of effectively unbounded CAPTCHA instances for backend-supported types. Re-establishes robust distinction between biological users and artificial agents through cognitive gap exploitation.
Conclusion: Next-Gen CAPTCHAs provide scalable, diverse defense mechanism against advanced multimodal agents by leveraging human cognitive advantages in interactive tasks requiring adaptive intuition.
Abstract: The rapid evolution of GUI-enabled agents has rendered traditional CAPTCHAs obsolete. While previous benchmarks like OpenCaptchaWorld established a baseline for evaluating multimodal agents, recent advancements in reasoning-heavy models, such as Gemini3-Pro-High and GPT-5.2-Xhigh have effectively collapsed this security barrier, achieving pass rates as high as 90% on complex logic puzzles like “Bingo”. In response, we introduce Next-Gen CAPTCHAs, a scalable defense framework designed to secure the next-generation web against the advanced agents. Unlike static datasets, our benchmark is built upon a robust data generation pipeline, allowing for large-scale and easily scalable evaluations, notably, for backend-supported types, our system is capable of generating effectively unbounded CAPTCHA instances. We exploit the persistent human-agent “Cognitive Gap” in interactive perception, memory, decision-making, and action. By engineering dynamic tasks that require adaptive intuition rather than granular planning, we re-establish a robust distinction between biological users and artificial agents, offering a scalable and diverse defense mechanism for the agentic era.
[844] The Benefits of Diversity: Combining Comparisons and Ratings for Efficient Scoring
Julien Fageot, Matthias Grossglauser, Lê-Nguyên Hoang, Matteo Tacchi-Bénard, Oscar Villemaud
Main category: cs.LG
TL;DR: SCoRa is a unified probabilistic model that combines individual ratings and pairwise comparisons to learn preference scores, outperforming methods using only one type of signal.
Details
Motivation: There's a long-standing debate about whether humans should evaluate entities individually (ratings) or comparatively (pairwise comparisons). The paper aims to show that combining both forms of preference elicitation can outperform focusing on a single kind, especially when accurate ordering of top entities is critical.Method: Introduces SCoRa (Scoring from Comparisons and Ratings), a unified probabilistic model that learns from both individual ratings and pairwise comparisons. The model has a MAP estimator with proven monotonicity and robustness guarantees.
Result: SCoRa recovers accurate scores even under model mismatch. The paper identifies realistic settings where combining comparisons and ratings outperforms using either one alone, particularly when accurate ordering of top entities is critical.
Conclusion: Combining both individual ratings and comparative evaluations provides better preference learning than using either method alone. SCoRa offers a versatile foundation for preference learning given the de facto availability of multiple forms of evaluation signals.
Abstract: Should humans be asked to evaluate entities individually or comparatively? This question has been the subject of long debates. In this work, we show that, interestingly, combining both forms of preference elicitation can outperform the focus on a single kind. More specifically, we introduce SCoRa (Scoring from Comparisons and Ratings), a unified probabilistic model that allows to learn from both signals. We prove that the MAP estimator of SCoRa is well-behaved. It verifies monotonicity and robustness guarantees. We then empirically show that SCoRa recovers accurate scores, even under model mismatch. Most interestingly, we identify a realistic setting where combining comparisons and ratings outperforms using either one alone, and when the accurate ordering of top entities is critical. Given the de facto availability of signals of multiple forms, SCoRa additionally offers a versatile foundation for preference learning.
[845] TAAM:Inductive Graph-Class Incremental Learning with Task-Aware Adaptive Modulation
Jingtao Liu, Xinming Zhang
Main category: cs.LG
TL;DR: TAAM introduces lightweight Neural Synapse Modulators for graph continual learning without replay, preventing catastrophic forgetting while handling unknown task IDs via Anchored Multi-hop Propagation.
Details
Motivation: Current graph continual learning methods rely on replay-based strategies with memory and privacy concerns, struggle with stability-plasticity dilemma, and existing benchmarks have flaws causing data leakage and biased evaluations.Method: Task-Aware Adaptive Modulation (TAAM) uses lightweight Neural Synapse Modulators (NSMs) - task-specific modules that perform node-attentive adaptive modulation on a fixed GNN backbone. For unknown task IDs, proposes Anchored Multi-hop Propagation (AMP) with theoretical proof.
Result: TAAM comprehensively outperforms state-of-the-art methods across eight datasets in rigorous inductive learning scenarios, demonstrating effectiveness without data replay.
Conclusion: Lightweight task-specific modules can effectively guide GNN reasoning for continual learning, preventing catastrophic forgetting without replay while handling unknown task scenarios.
Abstract: Graph Continual Learning (GCL) aims to solve the challenges of streaming graph data. However, current methods often depend on replay-based strategies, which raise concerns like memory limits and privacy issues, while also struggling to resolve the stability-plasticity dilemma. In this paper, we suggest that lightweight, task-specific modules can effectively guide the reasoning process of a fixed GNN backbone. Based on this idea, we propose Task-Aware Adaptive Modulation (TAAM). The key component of TAAM is its lightweight Neural Synapse Modulators (NSMs). For each new task, a dedicated NSM is trained and then frozen, acting as an “expert module.” These modules perform detailed, node-attentive adaptive modulation on the computational flow of a shared GNN backbone. This setup ensures that new knowledge is kept within compact, task-specific modules, naturally preventing catastrophic forgetting without using any data replay. Additionally, to address the important challenge of unknown task IDs in real-world scenarios, we propose and theoretically prove a novel method named Anchored Multi-hop Propagation (AMP). Notably, we find that existing GCL benchmarks have flaws that can cause data leakage and biased evaluations. Therefore, we conduct all experiments in a more rigorous inductive learning scenario. Extensive experiments show that TAAM comprehensively outperforms state-of-the-art methods across eight datasets. Code and Datasets are available at: https://github.com/1iuJT/TAAM_AAMAS2026.
[846] FIRE: Frobenius-Isometry Reinitialization for Balancing the Stability-Plasticity Tradeoff
Isaac Han, Sangyeon Park, Seungwon Oh, Donghu Kim, Hojoon Lee, Kyung-Joong Kim
Main category: cs.LG
TL;DR: FIRE: A principled reinitialization method that balances stability-plasticity tradeoff in neural networks by minimizing squared Frobenius error while maintaining weight isotropy.
Details
Motivation: Standard reinitialization methods for continual learning face a fundamental tradeoff: conservative approaches fail to restore plasticity for new tasks, while aggressive ones erase useful prior knowledge. There's a need for a principled method that explicitly balances stability (retaining past knowledge) and plasticity (adapting to new tasks).Method: FIRE quantifies stability through Squared Frobenius Error (SFE) measuring proximity to past weights, and plasticity through Deviation from Isometry (DfI) reflecting weight isotropy. The method solves a constrained optimization problem: minimize SFE subject to DfI being zero, which is efficiently approximated using Newton-Schulz iteration.
Result: FIRE outperforms both naive training without intervention and standard reinitialization methods across multiple domains: continual visual learning (CIFAR-10 with ResNet-18), language modeling (OpenWebText with GPT-0.1B), and reinforcement learning (HumanoidBench with SAC and Atari games with DQN).
Conclusion: FIRE provides an effective, principled approach to balancing the stability-plasticity tradeoff in continual learning scenarios, demonstrating consistent improvements across diverse domains including vision, language, and reinforcement learning tasks.
Abstract: Deep neural networks trained on nonstationary data must balance stability (i.e., retaining prior knowledge) and plasticity (i.e., adapting to new tasks). Standard reinitialization methods, which reinitialize weights toward their original values, are widely used but difficult to tune: conservative reinitializations fail to restore plasticity, while aggressive ones erase useful knowledge. We propose FIRE, a principled reinitialization method that explicitly balances the stability-plasticity tradeoff. FIRE quantifies stability through Squared Frobenius Error (SFE), measuring proximity to past weights, and plasticity through Deviation from Isometry (DfI), reflecting weight isotropy. The reinitialization point is obtained by solving a constrained optimization problem, minimizing SFE subject to DfI being zero, which is efficiently approximated by Newton-Schulz iteration. FIRE is evaluated on continual visual learning (CIFAR-10 with ResNet-18), language modeling (OpenWebText with GPT-0.1B), and reinforcement learning (HumanoidBench with SAC and Atari games with DQN). Across all domains, FIRE consistently outperforms both naive training without intervention and standard reinitialization methods, demonstrating effective balancing of the stability-plasticity tradeoff.
[847] V-ABFT: Variance-Based Adaptive Threshold for Fault-Tolerant Matrix Multiplication in Mixed-Precision Deep Learning
Yiheng Gao, Qin Hua, Zizhong Chen
Main category: cs.LG
TL;DR: V-ABFT: A variance-based adaptive threshold algorithm for fault tolerance in matrix multiplication that achieves tighter error bounds than existing methods by modeling verification differences statistically.
Details
Motivation: Existing Algorithm-Based Fault Tolerance (ABFT) methods for detecting silent data corruptions in matrix multiplication have overly conservative thresholds. Analytical bounds are too loose, while probabilistic approaches like A-ABFT produce thresholds 160-4200× larger than actual rounding errors, limiting detection sensitivity.Method: V-ABFT uses variance-based adaptive thresholding that directly models the verification difference. It leverages statistical variance estimation to compute tighter error bounds with only O(n) complexity using max/min/mean statistics, compared to A-ABFT’s O(pn) complexity for finding p largest values.
Result: V-ABFT reduces threshold-to-actual-error ratio to 7-20× for FP32/FP64 and 48-158× for BF16, representing 6-48× improvement over A-ABFT while maintaining zero false positive rate across multiple precisions. For fused-kernel implementations, it enables ~1000× finer detection granularity compared to offline verification.
Conclusion: V-ABFT provides significantly improved fault detection sensitivity for matrix multiplication operations in deep learning systems, is platform-agnostic, and has been successfully integrated into fault-tolerant GEMM implementations on both NPUs and GPUs.
Abstract: Algorithm-Based Fault Tolerance (ABFT) is widely adopted to detect silent data corruptions (SDCs) in matrix multiplication, a cornerstone operation in deep learning systems. However, existing threshold determination methods face critical challenges: analytical bounds are overly conservative, while probabilistic approaches like A-ABFT yield thresholds $160$–$4200\times$ larger than actual rounding errors. We present V-ABFT, a variance-based adaptive threshold algorithm that achieves tighter error bounds by directly modeling the verification difference. By leveraging statistical variance estimation, V-ABFT reduces the threshold-to-actual-error ratio to approximately $7$–$20\times$ for FP32/FP64 and $48$–$158\times$ for BF16, representing a \textbf{6–48$\times$ improvement} over A-ABFT while maintaining zero false positive rate across BF16, FP16, FP32, and FP64 precisions. Furthermore, we demonstrate that for fused-kernel ABFT implementations that verify before output quantization, low-precision GEMM can use FP32-level thresholds ($e_{\max} \approx 10^{-6}$), enabling \textbf{$\sim$1000$\times$ finer detection granularity} compared to offline verification with low-precision output ($e_{\max} \approx 10^{-3}$). We reproduce A-ABFT’s experimental setup and validate our implementation against the original paper’s results. Our method requires only $O(n)$ complexity using max/min/mean statistics, compared to A-ABFT’s $O(pn)$ for finding $p$ largest values. Extensive experiments on synthetic data and real model weights (LLaMA-7B, GPT-2, ViT) demonstrate V-ABFT’s effectiveness across diverse distributions. V-ABFT is platform-agnostic and has been integrated into fault-tolerant GEMM implementations on both NPUs and GPUs.
[848] Interpretable Fuzzy Systems For Forward Osmosis Desalination
Qusai Khaled, Uzay Kaymak, Laura Genga
Main category: cs.LG
TL;DR: Human-in-the-loop approach for interpretable fuzzy rule-based systems in water treatment, focusing on semantic interpretability through expert-guided partitioning and rule pruning.
Details
Motivation: Preserving interpretability in fuzzy rule-based systems is crucial for water treatment applications where decisions impact public health. While structural interpretability has been addressed, semantic interpretability often suffers due to fuzzy sets with low distinguishability.Method: Human-in-the-loop approach integrating expert-driven grid partitioning for distinguishable membership functions, domain-guided feature engineering to reduce redundancy, and rule pruning based on firing strength.
Result: Achieved comparable predictive performance to cluster-based FRBS while maintaining semantic interpretability and meeting structural complexity constraints for forward osmosis desalination productivity prediction.
Conclusion: Provides an explainable solution for water treatment applications that balances predictive performance with interpretability through human expert guidance.
Abstract: Preserving interpretability in fuzzy rule-based systems (FRBS) is vital for water treatment, where decisions impact public health. While structural interpretability has been addressed using multi-objective algorithms, semantic interpretability often suffers due to fuzzy sets with low distinguishability. We propose a human-in-the-loop approach for developing interpretable FRBS to predict forward osmosis desalination productivity. Our method integrates expert-driven grid partitioning for distinguishable membership functions, domain-guided feature engineering to reduce redundancy, and rule pruning based on firing strength. This approach achieved comparable predictive performance to cluster-based FRBS while maintaining semantic interpretability and meeting structural complexity constraints, providing an explainable solution for water treatment applications.
[849] Epigraph-Guided Flow Matching for Safe and Performant Offline Reinforcement Learning
Manan Tayal, Mumuksh Tayal
Main category: cs.LG
TL;DR: EpiFlow: A safe offline RL framework using epigraph-guided flow matching to co-optimize safety and performance without online exploration risks.
Details
Motivation: Existing safe offline RL methods struggle to balance safety, reward optimization, and data distribution adherence, often using soft constraints that allow violations or introduce excessive conservatism.Method: Formulates safe offline RL as state-constrained optimal control problem, learns feasibility value function via epigraph reformulation, and synthesizes policies by reweighting behavior distribution with flow matching for efficient sampling.
Result: Achieves competitive returns with near-zero empirical safety violations across safety-critical tasks including Safety-Gymnasium benchmarks.
Conclusion: EpiFlow effectively co-optimizes safety and performance through epigraph-guided policy synthesis, avoiding common pitfalls of prior safe offline RL approaches.
Abstract: Offline reinforcement learning (RL) provides a compelling paradigm for training autonomous systems without the risks of online exploration, particularly in safety-critical domains. However, jointly achieving strong safety and performance from fixed datasets remains challenging. Existing safe offline RL methods often rely on soft constraints that allow violations, introduce excessive conservatism, or struggle to balance safety, reward optimization, and adherence to the data distribution. To address this, we propose Epigraph-Guided Flow Matching (EpiFlow), a framework that formulates safe offline RL as a state-constrained optimal control problem to co-optimize safety and performance. We learn a feasibility value function derived from an epigraph reformulation of the optimal control problem, thereby avoiding the decoupled objectives or post-hoc filtering common in prior work. Policies are synthesized by reweighting the behavior distribution based on this epigraph value function and fitting a generative policy via flow matching, enabling efficient, distribution-consistent sampling. Across various safety-critical tasks, including Safety-Gymnasium benchmarks, EpiFlow achieves competitive returns with near-zero empirical safety violations, demonstrating the effectiveness of epigraph-guided policy synthesis.
[850] Compiler-Assisted Speculative Sampling for Accelerated LLM Inference on Heterogeneous Edge Devices
Alejandro Ruiz y Mesa, Guilherme Korol, Moritz Riesteter, João Paulo Cardoso de Lima, Jeronimo Castrillon
Main category: cs.LG
TL;DR: EdgeSpec: A compiler-based speculative decoding framework for LLMs on edge devices using analytical cost modeling and heterogeneous hardware partitioning to accelerate inference.
Details
Motivation: LLM deployment on resource-constrained edge devices faces severe latency constraints, especially for real-time applications where delayed responses compromise safety/usability. Speculative decoding shows promise but faces challenges: (1) integrating into compiler workflows without sacrificing performance/programmability, and (2) exploiting heterogeneous compute resources on modern SoCs through effective partitioning strategies.Method: Uses an analytical cost model to explore heterogeneous hardware configurations and guide coarse-grained partitioning of LLM subgraphs, particularly for edge-typical short input sequences. The model predicts when speculative sampling and heterogeneous execution are jointly beneficial, validated on edge devices with hexacore Cortex-A CPU and Mali GPU.
Result: Achieves up to 1.68× speedup for translation tasks on edge devices, closely matching analytic expectations. The framework successfully integrates speculative decoding into compiler workflows while exploiting heterogeneous hardware resources.
Conclusion: The proposed analytical cost modeling approach enables effective speculative decoding on edge devices by guiding hardware partitioning decisions, demonstrating significant speedups for real-world translation tasks while maintaining programmability.
Abstract: LLM deployment on resource-constrained edge devices faces severe latency constraints, particularly in real-time applications where delayed responses can compromise safety or usability. Among many approaches to mitigate the inefficiencies of sequential token-by-token generation, Speculative Decoding (SD) has emerged as a promising technique. However, SD at the edge is hindered by two major challenges: (1) integrating SD into a compiler-based workflow without sacrificing performance or programmability, and (2) exploiting the heterogeneous compute resources of modern SoCs through carefully designed partitioning strategies. This work addresses these challenges by using an analytical cost model that explores heterogeneous hardware configurations and guides coarse-grained partitioning of LLM subgraphs, particularly with edge-typical short input sequence lengths. The cost model predicts when speculative sampling and heterogeneous execution are jointly beneficial and is validated on an edge device featuring a hexacore Cortex-A CPU and a Mali GPU, revealing up to 1.68$\times$ speedup for translation tasks, closely matching analytic expectations.
[851] Efficient and Adaptable Detection of Malicious LLM Prompts via Bootstrap Aggregation
Shayan Ali Hassan, Tao Ni, Zafar Ayyub Qazi, Marco Canini
Main category: cs.LG
TL;DR: BAGEL is a lightweight, modular framework for malicious prompt detection using an ensemble of fine-tuned small models that can be incrementally updated to handle new attacks.
Details
Motivation: LLMs are vulnerable to malicious prompts (harmful requests, jailbreaks, prompt injections), but existing defenses have limitations: black-box APIs lack transparency, white-box LLM judges are computationally expensive, and current systems force trade-offs between performance, efficiency, and adaptability.Method: BAGEL uses bootstrap aggregation and mixture-of-experts inspired ensemble of fine-tuned models (86M parameters each) specialized on different attack datasets. It employs a random forest router to select the most suitable expert, then uses stochastic selection to sample additional members for prediction aggregation. The framework supports incremental updates by fine-tuning new classifiers for emerging attacks.
Result: BAGEL achieves F1 score of 0.92 using only 5 ensemble members (430M parameters total), outperforming OpenAI Moderation API and ShieldGemma which require billions of parameters. Performance remains robust after nine incremental updates, and the system provides interpretability through router structural features.
Conclusion: Ensembles of small fine-tuned classifiers can match or exceed billion-parameter guardrails while offering the adaptability and efficiency needed for production systems, demonstrating that lightweight modular approaches can effectively address malicious prompt detection.
Abstract: Large Language Models (LLMs) have demonstrated remarkable capabilities in natural language understanding, reasoning, and generation. However, these systems remain susceptible to malicious prompts that induce unsafe or policy-violating behavior through harmful requests, jailbreak techniques, and prompt injection attacks. Existing defenses face fundamental limitations: black-box moderation APIs offer limited transparency and adapt poorly to evolving threats, while white-box approaches using large LLM judges impose prohibitive computational costs and require expensive retraining for new attacks. Current systems force designers to choose between performance, efficiency, and adaptability. To address these challenges, we present BAGEL (Bootstrap AGgregated Ensemble Layer), a modular, lightweight, and incrementally updatable framework for malicious prompt detection. BAGEL employs a bootstrap aggregation and mixture of expert inspired ensemble of fine-tuned models, each specialized on a different attack dataset. At inference, BAGEL uses a random forest router to identify the most suitable ensemble member, then applies stochastic selection to sample additional members for prediction aggregation. When new attacks emerge, BAGEL updates incrementally by fine-tuning a small prompt-safety classifier (86M parameters) and adding the resulting model to the ensemble. BAGEL achieves an F1 score of 0.92 by selecting just 5 ensemble members (430M parameters), outperforming OpenAI Moderation API and ShieldGemma which require billions of parameters. Performance remains robust after nine incremental updates, and BAGEL provides interpretability through its router’s structural features. Our results show ensembles of small finetuned classifiers can match or exceed billion-parameter guardrails while offering the adaptability and efficiency required for production systems.
[852] Efficient Distribution Learning with Error Bounds in Wasserstein Distance
Eduardo Figueiredo, Steven Adams, Luca Laurenti
Main category: cs.LG
TL;DR: A framework for approximating unknown distributions from samples with guaranteed Wasserstein distance bounds using optimal transport and optimization.
Details
Motivation: Wasserstein distance is crucial for measuring distances between probability distributions in ML and other fields, but learning distributions with non-asymptotic, computable error bounds remains challenging.Method: Leverages optimal transport, nonlinear optimization, and concentration inequalities to bound Wasserstein distance via tractable mixed integer linear programs; develops intelligent clustering algorithms to find optimal support for approximate distributions.
Result: Outperforms state-of-the-art methods by returning distributions with substantially smaller support and tighter error bounds on benchmarks.
Conclusion: Provides an efficient framework for distribution approximation with guaranteed Wasserstein distance bounds, enabling practical applications across fields.
Abstract: The Wasserstein distance has emerged as a key metric to quantify distances between probability distributions, with applications in various fields, including machine learning, control theory, decision theory, and biological systems. Consequently, learning an unknown distribution with non-asymptotic and easy-to-compute error bounds in Wasserstein distance has become a fundamental problem in many fields. In this paper, we devise a novel algorithmic and theoretical framework to approximate an unknown probability distribution $\mathbb{P}$ from a finite set of samples by an approximate discrete distribution $\widehat{\mathbb{P}}$ while bounding the Wasserstein distance between $\mathbb{P}$ and $\widehat{\mathbb{P}}$. Our framework leverages optimal transport, nonlinear optimization, and concentration inequalities. In particular, we show that, even if $\mathbb{P}$ is unknown, the Wasserstein distance between $\mathbb{P}$ and $\widehat{\mathbb{P}}$ can be efficiently bounded with high confidence by solving a tractable optimization problem (a mixed integer linear program) of a size that only depends on the size of the support of $\widehat{\mathbb{P}}$. This enables us to develop intelligent clustering algorithms to optimally find the support of $\widehat{\mathbb{P}}$ while minimizing the Wasserstein distance error. On a set of benchmarks, we demonstrate that our approach outperforms state-of-the-art comparable methods by generally returning approximating distributions with substantially smaller support and tighter error bounds.
[853] Enhancing Bandit Algorithms with LLMs for Time-varying User Preferences in Streaming Recommendations
Chenglei Shen, Yi Zhan, Weijie Yu, Xiao Zhang, Jun Xu
Main category: cs.LG
TL;DR: HyperBandit+: A contextual bandit policy with time-aware hypernetwork and LLM-assisted warm-start for streaming recommendations with evolving user preferences.
Details
Motivation: Existing bandit methods treat time as mere timestamps, ignoring its relationship with user preferences, leading to suboptimal performance. Online learning methods also suffer from inefficient exploration-exploitation in early phases.Method: Uses time-aware hypernetwork to generate parameters for estimating time-varying rewards by capturing time-preference correlations. Employs LLM-assisted warm-start with multi-step data augmentation for offline learning. Uses low-rank factorization for real-time efficiency.
Result: Theoretical sublinear regret bound established. Extensive experiments on real-world datasets show HyperBandit+ consistently outperforms state-of-the-art baselines in accumulated rewards.
Conclusion: HyperBandit+ effectively addresses time-varying preferences and early-phase exploration challenges in streaming recommender systems through integrated time-aware modeling and LLM-assisted warm-start.
Abstract: In real-world streaming recommender systems, user preferences evolve dynamically over time. Existing bandit-based methods treat time merely as a timestamp, neglecting its explicit relationship with user preferences and leading to suboptimal performance. Moreover, online learning methods often suffer from inefficient exploration-exploitation during the early online phase. To address these issues, we propose HyperBandit+, a novel contextual bandit policy that integrates a time-aware hypernetwork to adapt to time-varying user preferences and employs a large language model-assisted warm-start mechanism (LLM Start) to enhance exploration-exploitation efficiency in the early online phase. Specifically, HyperBandit+ leverages a neural network that takes time features as input and generates parameters for estimating time-varying rewards by capturing the correlation between time and user preferences. Additionally, the LLM Start mechanism employs multi-step data augmentation to simulate realistic interaction data for effective offline learning, providing warm-start parameters for the bandit policy in the early online phase. To meet real-time streaming recommendation demands, we adopt low-rank factorization to reduce hypernetwork training complexity. Theoretically, we rigorously establish a sublinear regret upper bound that accounts for both the hypernetwork and the LLM warm-start mechanism. Extensive experiments on real-world datasets demonstrate that HyperBandit+ consistently outperforms state-of-the-art baselines in terms of accumulated rewards.
[854] Multimodal normative modeling in Alzheimers Disease with introspective variational autoencoders
Sayantan Kumar, Peijie Qiu, Aristeidis Sotiras
Main category: cs.LG
TL;DR: mmSIVAE: A multimodal soft-introspective VAE with Mixture-of-Product-of-Experts aggregation for normative modeling in Alzheimer’s disease, improving reference distribution fidelity and multimodal fusion for better anomaly detection.
Details
Motivation: Current VAE-based normative models for Alzheimer's disease have two key limitations: (1) imperfect fitting of healthy reference distributions leading to inflated false positives, and (2) weak multimodal fusion in shared latent space using posterior aggregation methods like PoE/MoE. These issues reduce the effectiveness of deviation-based analysis in multimodal neuroimaging.Method: Proposes mmSIVAE (multimodal soft-introspective variational autoencoder) with Mixture-of-Product-of-Experts (MOPOE) aggregation. Combines soft-introspective VAE for better reference distribution fitting with MOPOE for improved multimodal integration. Computes deviation scores in both latent space and feature space as distances from learned healthy distributions, and maps statistically significant latent deviations to regional abnormalities for interpretability.
Result: On ADNI MRI regional volumes and amyloid PET SUVR data, mmSIVAE improves reconstruction on held-out controls and produces more discriminative deviation scores for outlier detection than VAE baselines. Shows higher likelihood ratios and clearer separation between control and AD-spectrum cohorts. Deviation maps highlight region-level patterns aligned with established AD-related changes.
Conclusion: The study demonstrates the importance of training objectives that prioritize reference-distribution fidelity and robust multimodal posterior aggregation for normative modeling. The approach has implications for deviation-based analysis across multimodal clinical data, offering improved anomaly detection and interpretability in neurodegenerative disease analysis.
Abstract: Normative modeling learns a healthy reference distribution and quantifies subject-specific deviations to capture heterogeneous disease effects. In Alzheimers disease (AD), multimodal neuroimaging offers complementary signals but VAE-based normative models often (i) fit the healthy reference distribution imperfectly, inflating false positives, and (ii) use posterior aggregation (e.g., PoE/MoE) that can yield weak multimodal fusion in the shared latent space. We propose mmSIVAE, a multimodal soft-introspective variational autoencoder combined with Mixture-of-Product-of-Experts (MOPOE) aggregation to improve reference fidelity and multimodal integration. We compute deviation scores in latent space and feature space as distances from the learned healthy distributions, and map statistically significant latent deviations to regional abnormalities for interpretability. On ADNI MRI regional volumes and amyloid PET SUVR, mmSIVAE improves reconstruction on held-out controls and produces more discriminative deviation scores for outlier detection than VAE baselines, with higher likelihood ratios and clearer separation between control and AD-spectrum cohorts. Deviation maps highlight region-level patterns aligned with established AD-related changes. More broadly, our results highlight the importance of training objectives that prioritize reference-distribution fidelity and robust multimodal posterior aggregation for normative modeling, with implications for deviation-based analysis across multimodal clinical data.
[855] Spectral Guardrails for Agents in the Wild: Detecting Tool Use Hallucinations via Attention Topology
Valentin Noël
Main category: cs.LG
TL;DR: Spectral analysis of attention topology detects tool use failures and hallucinations in LLMs without training, achieving high recall/precision through single-layer spectral features.
Details
Motivation: Autonomous agents need reliable safeguards against tool use failures, but supervised approaches require labeled data. The paper proposes a training-free method to detect hallucinations and failures by analyzing attention patterns.Method: Uses spectral analysis of attention topology to detect hallucinations. Examines single-layer spectral features (smoothness, entropy) as detectors. Conducts cross-model evaluation on matched domains with controlled hallucination rates.
Result: Achieves 97.7% recall with multi-feature detection, 86.1% recall/81.0% precision for balanced deployment. Single-layer features work exceptionally well: Llama L26 Smoothness achieves 98.2% recall, Mistral L3 Entropy achieves 94.7% recall. Discovers “Loud Liar” phenomenon where Llama 3.1 failures are spectrally catastrophic and easier to detect.
Conclusion: Spectral analysis provides a principled, efficient framework for agent safety. Hallucination represents a thermodynamic state change where attention becomes noise. The method offers training-free detection complementary to supervised approaches.
Abstract: Deploying autonomous agents in the wild requires reliable safeguards against tool use failures. We propose a training free guardrail based on spectral analysis of attention topology that complements supervised approaches. On Llama 3.1 8B, our method achieves 97.7% recall with multi-feature detection and 86.1% recall with 81.0% precision for balanced deployment, without requiring any labeled training data. Most remarkably, we discover that single layer spectral features act as near-perfect hallucination detectors: Llama L26 Smoothness achieves 98.2% recall (213/217 hallucinations caught) with a single threshold, and Mistral L3 Entropy achieves 94.7% recall. This suggests hallucination is not merely a wrong token but a thermodynamic state change: the model’s attention becomes noise when it errs. Through controlled cross-model evaluation on matched domains ($N=1000$, $T=0.3$, same General domain, hallucination rates 20–22%), we reveal the ``Loud Liar’’ phenomenon: Llama 3.1 8B’s failures are spectrally catastrophic and dramatically easier to detect, while Mistral 7B achieves the best discrimination (AUC 0.900). These findings establish spectral analysis as a principled, efficient framework for agent safety.
[856] Probability Hacking and the Design of Trustworthy ML for Signal Processing in C-UAS: A Scenario Based Method
Liisa Janssens, Laura Middeldorp
Main category: cs.LG
TL;DR: Paper applies scenario-based method to Counter Unmanned Aircraft Systems (C-UAS) enhanced with Machine Learning, addressing probability hacking as a challenge and identifying requirements to strengthen trustworthiness for Human-Autonomy Teaming.
Details
Motivation: To enhance Counter Unmanned Aircraft Systems (C-UAS) with AI/ML for better threat countermeasures while addressing trustworthiness challenges like probability hacking that could undermine system reliability in civil and military contexts.Method: Uses scenario-based method applied to C-UAS augmented with Machine Learning, framing probability hacking as a challenge and identifying requirements that can be implemented in existing Rule of Law mechanisms.
Result: Identified requirements to prevent probability hacking that strengthen C-UAS trustworthiness, contributing to justified trust - a key component for successful Human-Autonomy Teaming.
Conclusion: Scenario-based method helps address AI/ML trustworthiness challenges in C-UAS systems, providing requirements to prevent probability hacking and enhance trust for effective Human-Autonomy Teaming in security applications.
Abstract: In order to counter the various threats manifested by Unmanned Aircraft Systems (UAS) adequately, specialized Counter Unmanned Aircraft Systems (C-UAS) are required. Enhancing C-UAS with Emerging and Disruptive Technologies (EDTs) such as Artificial Intelligence (AI) can lead to more effective countermeasures. In this paper a scenario-based method is applied to C-UAS augmented with Machine Learning (ML), a subset of AI, that can enhance signal processing capabilities. Via the scenarios-based method we frame in this paper probability hacking as a challenge and identify requirements which can be implemented in existing Rule of Law mechanisms to prevent probability hacking. These requirements strengthen the trustworthiness of the C-UAS, which feed into justified trust - a key to successful Human-Autonomy Teaming, in civil and military contexts. Index Terms: C-UAS, Scenario-based method, Emerging and Disruptive Technologies, Probability hacking, Trustworthiness.
[857] Online Domain-aware LLM Decoding for Continual Domain Evolution
Mohammad Abu-Shaira, Weishi Shi
Main category: cs.LG
TL;DR: ODD framework enables real-time LLM adaptation to evolving domains using probability-level fusion with prefix-tree priors and adaptive confidence modulation
Details
Motivation: Domain knowledge evolves continuously (new regulations, products, services, interaction patterns), making offline fine-tuning insufficient. Real-world environments exhibit temporal dynamics and concept drift, which can significantly reduce model accuracy. There's a need for efficient real-time adaptation without costly retraining.Method: Online Domain-aware Decoding (ODD) framework performs probability-level fusion between a base LLM and a prefix-tree prior, guided by adaptive confidence modulation using disagreement and continuity signals.
Result: ODD consistently surpasses LLM-Greedy and LLM-Temp Scaled across all syntactic and semantic NLG metrics. Achieves absolute ROUGE-L gain of 0.065 and 13.6% relative improvement in Cosine Similarity over best baseline.
Conclusion: ODD demonstrates robustness to evolving lexical and contextual patterns, making it suitable for dynamic LLM applications that need to adapt to changing domains without retraining.
Abstract: LLMs are typically fine-tuned offline on domain-specific data, assuming a static domain. In practice, domain knowledge evolves continuously through new regulations, products, services, and interaction patterns. Retraining or fine-tuning LLMs for every new instance is computationally infeasible. Additionally, real-world environments also exhibit temporal dynamics with shifting data distributions. Disregarding this phenomenon, commonly referred to as concept drift, can significantly diminish a model’s predictive accuracy. This mismatch between evolving domains and static adaptation pipelines highlights the need for efficient, real-time adaptation without costly retraining. In response, we introduce Online Domain-aware Decoding framework (ODD). ODD performs probability-level fusion between a base LLM and a prefix-tree prior, guided by adaptive confidence modulation using disagreement and continuity signals. Empirical evaluation under diverse drift scenarios demonstrates that ODD consistently surpasses LLM-Greedy and LLM-Temp Scaled across all syntactic and semantic NLG metrics. It yields an absolute ROUGE-L gain of 0.065 and a 13.6% relative improvement in Cosine Similarity over the best baseline. These results demonstrate ODD ’s robustness to evolving lexical and contextual patterns, making it suitable for dynamic LLM applications.
[858] Mutual information and task-relevant latent dimensionality
Paarth Gulati, Eslam Abdelaleem, Audrey Sederberg, Ilya Nemenman
Main category: cs.LG
TL;DR: A method for estimating task-relevant latent dimensionality using Information Bottleneck principles with a hybrid critic architecture that avoids systematic inflation of dimension estimates.
Details
Motivation: Estimating the dimensionality of latent representations needed for prediction (task-relevant dimension) is a difficult unsolved problem with broad scientific applications. Current neural mutual information estimators with separable/bilinear critics systematically inflate inferred dimensions.Method: Cast dimensionality estimation as an Information Bottleneck question: what embedding bottleneck dimension preserves mutual information between predictor and predicted views. Introduce hybrid critic that retains explicit dimensional bottleneck while allowing flexible nonlinear cross-view interactions. Propose one-shot protocol that reads effective dimension from single over-parameterized hybrid model without sweeping bottleneck sizes.
Result: Validated on synthetic problems with known task-relevant dimension. Extended to intrinsic dimensionality by constructing paired views of single dataset. Approach remains reliable in noisy regimes where classical geometric estimators degrade. Demonstrated utility on multiple physics datasets.
Conclusion: The Information Bottleneck framework with hybrid critic architecture provides reliable dimensionality estimation that avoids systematic inflation, works in noisy regimes, and has practical applications across scientific domains.
Abstract: Estimating the dimensionality of the latent representation needed for prediction – the task-relevant dimension – is a difficult, largely unsolved problem with broad scientific applications. We cast it as an Information Bottleneck question: what embedding bottleneck dimension is sufficient to compress predictor and predicted views while preserving their mutual information (MI). This repurposes neural MI estimators for dimensionality estimation. We show that standard neural estimators with separable/bilinear critics systematically inflate the inferred dimension, and we address this by introducing a hybrid critic that retains an explicit dimensional bottleneck while allowing flexible nonlinear cross-view interactions, thereby preserving the latent geometry. We further propose a one-shot protocol that reads off the effective dimension from a single over-parameterized hybrid model, without sweeping over bottleneck sizes. We validate the approach on synthetic problems with known task-relevant dimension. We extend the approach to intrinsic dimensionality by constructing paired views of a single dataset, enabling comparison with classical geometric dimension estimators. In noisy regimes where those estimators degrade, our approach remains reliable. Finally, we demonstrate the utility of the method on multiple physics datasets.
[859] Variance-Gated Ensembles: An Epistemic-Aware Framework for Uncertainty Estimation
H. Martin Gillis, Isaac Xu, Thomas Trappenberg
Main category: cs.LG
TL;DR: Variance-Gated Ensembles (VGE) introduces a differentiable framework for epistemic-aware uncertainty estimation in ensemble models using variance-gated mechanisms, providing practical and scalable uncertainty decomposition without relying on additive decomposition.
Details
Motivation: Traditional additive decomposition of uncertainty into aleatoric and epistemic components breaks down with finite-ensemble sampling and mismatched predictive distributions, creating a need for more reliable uncertainty estimation methods in machine learning applications.Method: VGE uses variance-gated mechanisms: (1) Variance-Gated Margin Uncertainty (VGMU) score coupling decision margins with ensemble predictive variance, and (2) Variance-Gated Normalization (VGN) layer enabling per-class, learnable normalization of ensemble member probabilities. The framework computes signal-to-noise gates from ensemble statistics and provides closed-form vector-Jacobian products for end-to-end training.
Result: VGE matches or exceeds state-of-the-art information-theoretic baselines while remaining computationally efficient, providing a practical and scalable approach to epistemic-aware uncertainty estimation in ensemble models.
Conclusion: VGE offers an intuitive, differentiable framework that addresses limitations of additive uncertainty decomposition, enabling more reliable per-sample uncertainty estimation in ensemble models with open-source implementation available.
Abstract: Machine learning applications require fast and reliable per-sample uncertainty estimation. A common approach is to use predictive distributions from Bayesian or approximation methods and additively decompose uncertainty into aleatoric (i.e., data-related) and epistemic (i.e., model-related) components. However, additive decomposition has recently been questioned, with evidence that it breaks down when using finite-ensemble sampling and/or mismatched predictive distributions. This paper introduces Variance-Gated Ensembles (VGE), an intuitive, differentiable framework that injects epistemic sensitivity via a signal-to-noise gate computed from ensemble statistics. VGE provides: (i) a Variance-Gated Margin Uncertainty (VGMU) score that couples decision margins with ensemble predictive variance; and (ii) a Variance-Gated Normalization (VGN) layer that generalizes the variance-gated uncertainty mechanism to training via per-class, learnable normalization of ensemble member probabilities. We derive closed-form vector-Jacobian products enabling end-to-end training through ensemble sample mean and variance. VGE matches or exceeds state-of-the-art information-theoretic baselines while remaining computationally efficient. As a result, VGE provides a practical and scalable approach to epistemic-aware uncertainty estimation in ensemble models. An open-source implementation is available at: https://github.com/nextdevai/vge.
[860] A second order regret bound for NormalHedge
Yoav Freund, Nicholas J. A. Harvey, Victor S. Portella, Yabing Qi, Yu-Xiang Wang
Main category: cs.LG
TL;DR: Variant of NormalHedge algorithm achieves improved second-order regret bounds for “easy” sequences in prediction with expert advice
Details
Motivation: The paper aims to develop better regret bounds for prediction with expert advice problems, particularly for "easy" sequences where the cumulative second moment of regret is smallMethod: Develops a variant of NormalHedge algorithm inspired by continuous-time Stochastic Differential Equations, with discrete-time analysis using self-concordance techniques
Result: Achieves second-order ε-quantile regret bound of O(√(V_T log(V_T/ε))) when V_T > log N, where V_T is cumulative second moment of instantaneous per-expert regret
Conclusion: The algorithm provides improved theoretical guarantees for prediction with expert advice on “easy” sequences through novel continuous-time inspiration and self-concordance analysis
Abstract: We consider the problem of prediction with expert advice for ``easy’’ sequences. We show that a variant of NormalHedge enjoys a second-order $ε$-quantile regret bound of $O\big(\sqrt{V_T \log(V_T/ε)}\big) $ when $V_T > \log N$, where $V_T$ is the cumulative second moment of instantaneous per-expert regret averaged with respect to a natural distribution determined by the algorithm. The algorithm is motivated by a continuous time limit using Stochastic Differential Equations. The discrete time analysis uses self-concordance techniques.
[861] A Causal Machine Learning Framework for Treatment Personalization in Clinical Trials: Application to Ulcerative Colitis
Cristian Minoccheri, Sophia Tesic, Kayvan Najarian, Ryan Stidham
Main category: cs.LG
TL;DR: A causal ML framework evaluates treatment effect heterogeneity vs. actual decision improvement, showing statistical heterogeneity doesn’t always translate to better treatment decisions in ulcerative colitis trial.
Details
Motivation: While RCTs estimate average treatment effects, personalized medicine needs understanding of treatment response heterogeneity. However, statistically detectable heterogeneity doesn't necessarily mean it improves actual treatment decisions - these are distinct questions that can yield contradictory answers.Method: Modular causal ML framework with three components: permutation importance identifies features predicting heterogeneity, BLP testing assesses statistical significance, and doubly robust policy evaluation measures whether acting on heterogeneity improves patient outcomes. Applied to UNIFI ulcerative colitis trial data comparing placebo, standard-dose, and dose-intensified ustekinumab using cross-fitted X-learner models with various features.
Result: BLP testing found strong associations between endoscopic features and treatment effect heterogeneity, but doubly robust policy evaluation showed no improvement in expected remission from using endoscopic features, with worse performance in multi-arm evaluation. Endoscopic scores acted as disease severity markers (good for outcome prediction but added noise to treatment selection), while clinical variables captured decision-relevant variation.
Conclusion: Causal ML applications to clinical trials should include policy-level evaluation alongside heterogeneity testing, as statistical heterogeneity doesn’t guarantee improved treatment decisions.
Abstract: Randomized controlled trials estimate average treatment effects, but treatment response heterogeneity motivates personalized approaches. A critical question is whether statistically detectable heterogeneity translates into improved treatment decisions – these are distinct questions that can yield contradictory answers. We present a modular causal machine learning framework that evaluates each question separately: permutation importance identifies which features predict heterogeneity, best linear predictor (BLP) testing assesses statistical significance, and doubly robust policy evaluation measures whether acting on the heterogeneity improves patient outcomes. We apply this framework to patient-level data from the UNIFI maintenance trial of ustekinumab in ulcerative colitis, comparing placebo, standard-dose ustekinumab every 12 weeks, and dose-intensified ustekinumab every 8 weeks, using cross-fitted X-learner models with baseline demographics, medication history, week-8 clinical scores, laboratory biomarkers, and video-derived endoscopic features. BLP testing identified strong associations between endoscopic features and treatment effect heterogeneity for ustekinumab versus placebo, yet doubly robust policy evaluation showed no improvement in expected remission from incorporating endoscopic features, and out-of-fold multi-arm evaluation showed worse performance. Diagnostic comparison of prognostic contribution against policy value revealed that endoscopic scores behaved as disease severity markers – improving outcome prediction in untreated patients but adding noise to treatment selection – while clinical variables (fecal calprotectin, age, CRP) captured the decision-relevant variation. These results demonstrate that causal machine learning applications to clinical trials should include policy-level evaluation alongside heterogeneity testing.
[862] Nansde-net: A neural sde framework for generating time series with memory
Hiromu Ozai, Kei Nakagawa
Main category: cs.LG
TL;DR: A novel neural SDE framework with neural network-parameterized ARMA-type noise (NA-noise) that captures both long- and short-memory time series characteristics while maintaining compatibility with Itô calculus.
Details
Motivation: Existing fractional Brownian motion models for capturing memory effects in time series are incompatible with Itô calculus, limiting their use in neural SDE frameworks. There's a need for noise processes that can capture both long- and short-memory behaviors while remaining within the Itô calculus framework.Method: Proposes Neural Network-kernel ARMA-type noise (NA-noise) - an Itô-process-based alternative with neural network-parameterized kernel functions decomposed into product form to preserve Markov property. Develops NANSDE-Net, a generative model extending Neural SDEs with NA-noise, with theoretical guarantees and efficient backpropagation.
Result: NANSDE-Net matches or outperforms existing models (including fractional SDE-Net) in reproducing long- and short-memory features on synthetic and real-world datasets, while maintaining computational tractability within Itô calculus framework.
Conclusion: The proposed NA-noise provides a flexible, theoretically sound alternative to fractional Brownian motion for capturing memory effects in neural SDEs, enabling better modeling of time series with memory characteristics while staying within standard stochastic calculus frameworks.
Abstract: Modeling time series with long- or short-memory characteristics is a fundamental challenge in many scientific and engineering domains. While fractional Brownian motion has been widely used as a noise source to capture such memory effects, its incompatibility with Itô calculus limits its applicability in neural stochastic differential equation~(SDE) frameworks. In this paper, we propose a novel class of noise, termed Neural Network-kernel ARMA-type noise~(NA-noise), which is an Itô-process-based alternative capable of capturing both long- and short-memory behaviors. The kernel function defining the noise structure is parameterized via neural networks and decomposed into a product form to preserve the Markov property. Based on this noise process, we develop NANSDE-Net, a generative model that extends Neural SDEs by incorporating NA-noise. We prove the theoretical existence and uniqueness of the solution under mild conditions and derive an efficient backpropagation scheme for training. Empirical results on both synthetic and real-world datasets demonstrate that NANSDE-Net matches or outperforms existing models, including fractional SDE-Net, in reproducing long- and short-memory features of the data, while maintaining computational tractability within the Itô calculus framework.
[863] Interpretable Dynamic Network Modeling of Tensor Time Series via Kronecker Time-Varying Graphical Lasso
Shingo Higashiguchi, Koki Kawabata, Yasuko Matsubara, Yasushi Sakurai
Main category: cs.LG
TL;DR: KTVGL is a method for modeling tensor time series that estimates mode-specific dynamic networks in Kronecker product form, improving interpretability and computational efficiency.
Details
Motivation: Real-world tensor time series data with multiple modes creates large, entangled networks that are hard to interpret and computationally intensive to estimate, requiring methods that can handle these complexities efficiently.Method: Proposes Kronecker Time-Varying Graphical Lasso (KTVGL) that estimates mode-specific dynamic networks in Kronecker product form, preventing exponential computational growth and enabling stream algorithms.
Result: Experiments show KTVGL achieves higher edge estimation accuracy than existing methods while requiring less computation time, with practical value demonstrated through real-world case studies.
Conclusion: KTVGL provides an efficient and interpretable solution for modeling dynamic networks in tensor time series, with computational advantages that scale well with data dimensions.
Abstract: With the rapid development of web services, large amounts of time series data are generated and accumulated across various domains such as finance, healthcare, and online platforms. As such data often co-evolves with multiple variables interacting with each other, estimating the time-varying dependencies between variables (i.e., the dynamic network structure) has become crucial for accurate modeling. However, real-world data is often represented as tensor time series with multiple modes, resulting in large, entangled networks that are hard to interpret and computationally intensive to estimate. In this paper, we propose Kronecker Time-Varying Graphical Lasso (KTVGL), a method designed for modeling tensor time series. Our approach estimates mode-specific dynamic networks in a Kronecker product form, thereby avoiding overly complex entangled structures and producing interpretable modeling results. Moreover, the partitioned network structure prevents the exponential growth of computational time with data dimension. In addition, our method can be extended to stream algorithms, making the computational time independent of the sequence length. Experiments on synthetic data show that the proposed method achieves higher edge estimation accuracy than existing methods while requiring less computation time. To further demonstrate its practical value, we also present a case study using real-world data. Our source code and datasets are available at https://github.com/Higashiguchi-Shingo/KTVGL.
[864] CADO: From Imitation to Cost Minimization for Heatmap-based Solvers in Combinatorial Optimization
Hyungseok Song, Deunsol Yoon, Kanghoon Lee, Han-Seul Jeong, Soonyoung Lee, Woohyung Lim
Main category: cs.LG
TL;DR: CADO introduces a reinforcement learning framework for heatmap-based combinatorial optimization solvers that directly optimizes solution cost rather than imitation loss, overcoming limitations of supervised learning approaches.
Details
Motivation: Current heatmap-based combinatorial optimization solvers using supervised learning suffer from objective mismatch: minimizing imitation loss (cross-entropy) doesn't guarantee solution cost minimization. This creates two deficiencies: Decoder-Blindness (ignoring non-differentiable decoding) and Cost-Blindness (prioritizing structural imitation over solution quality).Method: Proposes CADO (Cost-Aware Diffusion models for Optimization), a reinforcement learning fine-tuning framework that formulates diffusion denoising as an MDP to directly optimize post-decoded solution cost. Uses Label-Centered Reward (repurposing ground-truth labels as unbiased baselines) and Hybrid Fine-Tuning for parameter-efficient adaptation.
Result: CADO achieves state-of-the-art performance across diverse combinatorial optimization benchmarks, validating that objective alignment is essential for unlocking the full potential of heatmap-based solvers.
Conclusion: Direct optimization of solution cost through reinforcement learning overcomes the fundamental limitations of supervised learning for heatmap-based combinatorial optimization, enabling better performance by aligning training objectives with actual solution quality metrics.
Abstract: Heatmap-based solvers have emerged as a promising paradigm for Combinatorial Optimization (CO). However, we argue that the dominant Supervised Learning (SL) training paradigm suffers from a fundamental objective mismatch: minimizing imitation loss (e.g., cross-entropy) does not guarantee solution cost minimization. We dissect this mismatch into two deficiencies: Decoder-Blindness (being oblivious to the non-differentiable decoding process) and Cost-Blindness (prioritizing structural imitation over solution quality). We empirically demonstrate that these intrinsic flaws impose a hard performance ceiling. To overcome this limitation, we propose CADO (Cost-Aware Diffusion models for Optimization), a streamlined Reinforcement Learning fine-tuning framework that formulates the diffusion denoising process as an MDP to directly optimize the post-decoded solution cost. We introduce Label-Centered Reward, which repurposes ground-truth labels as unbiased baselines rather than imitation targets, and Hybrid Fine-Tuning for parameter-efficient adaptation. CADO achieves state-of-the-art performance across diverse benchmarks, validating that objective alignment is essential for unlocking the full potential of heatmap-based solvers.
[865] Distribution-Free Robust Functional Predict-Then-Optimize
Yash Patel, Ambuj Tewari
Main category: cs.LG
TL;DR: Conformal prediction for uncertainty quantification in neural operator PDE surrogates, enabling robust decision-making with formal regret guarantees.
Details
Motivation: Neural operator surrogate models for PDEs lack calibrated uncertainty quantification. Current methods (ensembling, Bayesian approaches) have distributional assumptions or scalability issues, limiting practical applications in decision-making tasks.Method: Proposes applying conformal prediction to neural operators for distribution-free uncertainty quantification over function spaces. Uses infinite-dimensional generalization of Danskin’s Theorem and calculus of variations to solve robust decision-making tasks efficiently.
Result: Demonstrates superior performance over restrictive modeling paradigms like Gaussian Processes across several engineering tasks. Shows how prediction regions enable formal regret characterization in downstream robust decision-making.
Conclusion: Conformal prediction provides practical, distribution-free uncertainty quantification for neural operator PDE surrogates, enabling robust decision-making with formal guarantees and better performance than existing methods.
Abstract: The solution of PDEs in decision-making tasks is increasingly being undertaken with the help of neural operator surrogate models due to the need for repeated evaluation. Such methods, while significantly more computationally favorable compared to their numerical counterparts, fail to provide any calibrated notions of uncertainty in their predictions. Current methods approach this deficiency typically with ensembling or Bayesian posterior estimation. However, these approaches either require distributional assumptions that fail to hold in practice or lack practical scalability, limiting their applications in practice. We, therefore, propose a novel application of conformal prediction to produce distribution-free uncertainty quantification over the function spaces mapped by neural operators. We then demonstrate how such prediction regions enable a formal regret characterization if leveraged in downstream robust decision-making tasks. We further demonstrate how such posited robust decision-making tasks can be efficiently solved using an infinite-dimensional generalization of Danskin’s Theorem and calculus of variations and empirically demonstrate the superior performance of our proposed method over more restrictive modeling paradigms, such as Gaussian Processes, across several engineering tasks.
[866] Thermodynamic Isomorphism of Transformers: A Lagrangian Approach to Attention Dynamics
Gunn Kim
Main category: cs.LG
TL;DR: A first-principles physics framework for Transformers that treats attention as a physical system governed by least action, mapping information states to Riemannian manifolds and deriving an intelligence Lagrangian.
Details
Motivation: Transformers have revolutionized AI but lack a unified physical theory. The paper aims to establish a first-principles framework for information dynamics by treating attention as a physical system rather than algorithmic optimization.Method: Map information states to a Riemannian manifold using the Fisher information metric, derive an intelligence Lagrangian, show softmax corresponds to thermodynamic equilibrium minimizing Helmholtz free energy, and identify query-key interactions as electrodynamic coupling.
Result: Establishes the first law of information thermodynamics unifying inference and learning, explains emergent phenomena like scaling laws and grokking as phase transitions, and shows how rotational symmetry breaking generates massless Goldstone bosons related to rotary positional embeddings.
Conclusion: Connects statistical physics and deep learning, providing a field-theoretic perspective on Transformers and laying groundwork for a general theory of physics-based intelligence.
Abstract: Although the Transformer architecture has revolutionized artificial intelligence, its underlying mechanisms remain largely heuristic and lack a unified physical theory. In this work, we propose a first-principles framework for information dynamics, treating the attention mechanism as a physical system governed by the principle of least action rather than as an algorithmic optimization. By mapping information states to a Riemannian manifold with the Fisher information metric, we derive the intelligence Lagrangian. We show that the softmax function corresponds to the unique thermodynamic equilibrium state that minimizes the Helmholtz free energy of the information gas. In addition, we identify the query-key interaction as an electrodynamic coupling between an external field and an intrinsic dipole moment. This theory establishes the first law of information thermodynamics, unifying inference (mechanical work) and learning (chemical evolution). It also explains emergent phenomena, such as scaling laws and grokking, as phase transitions characterized by the divergence of specific heat. Finally, we discuss how rotational symmetry breaking in the attention manifold generates massless Goldstone bosons, providing a field-theoretic perspective on rotary positional embeddings (RoPE). Our work connects Statistical Physics and Deep Learning, laying the groundwork for a general theory of physics-based intelligence.
[867] Sparsity-Aware Evolution for Model Merging
Huan Zhang, Yanjian Zhang, Guillaume Wisniewski, Nadi Tomeh, Bang Liu
Main category: cs.LG
TL;DR: SAE framework for model merging uses evolutionary algorithms with sparsity-aware mutation operators to improve merging reliability across LLM benchmarks.
Details
Motivation: Model merging techniques often face reliability issues, and existing approaches don't effectively incorporate sparsity constraints to guide the merging process toward more efficient models.Method: Proposes a sparsity-aware evolutionary framework with iterative pruning-merging cycles as mutation operators, incorporating sparsity constraints into the score function alongside conventional performance metrics.
Result: Improves model merging reliability across multiple large-scale LLM benchmarks, with the approach being simple and orthogonal to most existing methods.
Conclusion: The SAE framework effectively combines evolutionary algorithms with sparsity awareness to enhance model merging, introducing novel competitive dynamics that improve both performance and efficiency.
Abstract: We propose a sparsity-aware evolutionary (SAE) framework for model merging that involves iterative pruning-merging cycles to act as a novel mutation operator. We incorporate the sparsity constraints into the score function, which steers the evolutionary process to favor more sparse models, in addition to other conventional performance scores. Interestingly, the by-product of \textit{competition} for sparsity introduces an extra local \textit{attraction} and interplay into the evolutionary process: if one competitor has more zero elements, the other competitor’s non-zero elements will occupy those positions, even though the less sparse competitor loses to the more sparse competitor in other positions. The proposed pipeline is evaluated on a variety of large-scale LLM benchmarks. Experiments demonstrate that our approach can improve model merging reliability across multiple benchmarks, and is easy to incorporate due to its simplicity and being orthogonal to most existing approaches.
[868] SkillRL: Evolving Agents via Recursive Skill-Augmented Reinforcement Learning
Peng Xia, Jianwen Chen, Hanyang Wang, Jiaqi Liu, Kaide Zeng, Yu Wang, Siwei Han, Yiyang Zhou, Xujiang Zhao, Haifeng Chen, Zeyu Zheng, Cihang Xie, Huaxiu Yao
Main category: cs.LG
TL;DR: SkillRL: A framework for LLM agents that automatically discovers and evolves reusable skills from experience to improve generalization and reduce token usage.
Details
Motivation: Current LLM agents operate in isolation without learning from past experiences. Existing memory methods store raw trajectories that are redundant and noisy, preventing extraction of high-level behavioral patterns needed for generalization.Method: Proposes SkillRL with three key components: 1) Experience-based distillation to build hierarchical skill library (SkillBank), 2) Adaptive retrieval strategy for general and task-specific heuristics, 3) Recursive evolution mechanism where skill library co-evolves with agent’s policy during reinforcement learning.
Result: Achieves state-of-the-art performance on ALFWorld, WebShop and seven search-augmented tasks, outperforming strong baselines by over 15.3%. Maintains robustness as task complexity increases while significantly reducing token footprint.
Conclusion: SkillRL successfully bridges the gap between raw experience and policy improvement through automatic skill discovery and evolution, enabling LLM agents to learn reusable behavioral patterns for better generalization.
Abstract: Large Language Model (LLM) agents have shown stunning results in complex tasks, yet they often operate in isolation, failing to learn from past experiences. Existing memory-based methods primarily store raw trajectories, which are often redundant and noise-heavy. This prevents agents from extracting high-level, reusable behavioral patterns that are essential for generalization. In this paper, we propose SkillRL, a framework that bridges the gap between raw experience and policy improvement through automatic skill discovery and recursive evolution. Our approach introduces an experience-based distillation mechanism to build a hierarchical skill library SkillBank, an adaptive retrieval strategy for general and task-specific heuristics, and a recursive evolution mechanism that allows the skill library to co-evolve with the agent’s policy during reinforcement learning. These innovations significantly reduce the token footprint while enhancing reasoning utility. Experimental results on ALFWorld, WebShop and seven search-augmented tasks demonstrate that SkillRL achieves state-of-the-art performance, outperforming strong baselines over 15.3% and maintaining robustness as task complexity increases. Code is available at this https://github.com/aiming-lab/SkillRL.
[869] Linearization Explains Fine-Tuning in Large Language Models
Zahra Rahimi Afzal, Tara Esmaeilbeig, Mojtaba Soltanalian, Mesrob I. Ohannessian
Main category: cs.LG
TL;DR: Analysis of Parameter-Efficient Fine-Tuning (PEFT) through linearization lens, showing fine-tuning dynamics become equivalent to learning with neural tangent kernel (NTK) when using Euclidean distance regularization, revealing correlation between NTK eigenvalue spectrum and adaptation performance.
Details
Motivation: PEFT techniques are widely used for adapting large models efficiently, but their underlying mechanisms for training performance and generalization are not well understood. The paper aims to provide insights into fine-tuning through mathematical analysis of linearization.Method: Uses linearization theory to analyze fine-tuning dynamics, showing that with Euclidean distance regularization in parameter space, fine-tuning becomes equivalent to learning with positive-definite NTK. Analyzes relationship between linear and linearized fine-tuning based on regularization strength, and provides spectral perturbation bounds on NTK induced by layer selection choices.
Result: Reveals strong correlation between NTK eigenvalue spectrum and model adaptation performance when linearization is a good model. Empirically validates theory on LoRA for LLMs, showing insights characterize fine-tuning and can potentially enhance PEFT techniques.
Conclusion: Linearization provides valuable theoretical framework for understanding PEFT mechanisms, with NTK eigenvalue spectrum serving as predictor for adaptation performance. These insights can lead to better-informed and more efficient adaptation strategies for large language models.
Abstract: Parameter-Efficient Fine-Tuning (PEFT) is a popular class of techniques that strive to adapt large models in a scalable and resource-efficient manner. Yet, the mechanisms underlying their training performance and generalization remain underexplored. In this paper, we provide several insights into such fine-tuning through the lens of linearization. Fine-tuned models are often implicitly encouraged to remain close to the pretrained model. By making this explicit, using an Euclidean distance inductive bias in parameter space, we show that fine-tuning dynamics become equivalent to learning with the positive-definite neural tangent kernel (NTK). We specifically analyze how close the fully linear and the linearized fine-tuning optimizations are, based on the strength of the regularization. This allows us to be pragmatic about how good a model linearization is when fine-tuning large language models (LLMs). When linearization is a good model, our findings reveal a strong correlation between the eigenvalue spectrum of the NTK and the performance of model adaptation. Motivated by this, we give spectral perturbation bounds on the NTK induced by the choice of layers selected for fine-tuning. We empirically validate our theory on Low Rank Adaptation (LoRA) on LLMs. These insights not only characterize fine-tuning but also have the potential to enhance PEFT techniques, paving the way to better informed and more nimble adaptation in LLMs.
[870] Learning in Context, Guided by Choice: A Reward-Free Paradigm for Reinforcement Learning with Transformers
Juncheng Dong, Bowen He, Moyang Guo, Ethan X. Fang, Zhuoran Yang, Vahid Tarokh
Main category: cs.LG
TL;DR: ICPRL enables in-context reinforcement learning using only preference feedback instead of explicit rewards, with two variants (I-PRL for per-step and T-PRL for trajectory-level preferences) that achieve comparable performance to reward-supervised methods.
Details
Motivation: Existing in-context reinforcement learning methods require explicit reward signals during pretraining, which limits applicability when rewards are ambiguous, hard to specify, or costly to obtain. The paper aims to overcome this limitation by using only preference feedback.Method: Proposes In-Context Preference-based Reinforcement Learning (ICPRL) with two variants: Immediate Preference-based RL (I-PRL) using per-step preferences, and Trajectory Preference-based RL (T-PRL) using trajectory-level comparisons. Introduces preference-native frameworks that directly optimize transformer policies from preference data without requiring reward signals or optimal action labels.
Result: Experiments on dueling bandits, navigation, and continuous control tasks show that ICPRL enables strong in-context generalization to unseen tasks, achieving performance comparable to ICRL methods trained with full reward supervision.
Conclusion: ICPRL successfully demonstrates that in-context reinforcement learning can be performed using only preference feedback, eliminating the need for explicit reward supervision while maintaining strong generalization capabilities.
Abstract: In-context reinforcement learning (ICRL) leverages the in-context learning capabilities of transformer models (TMs) to efficiently generalize to unseen sequential decision-making tasks without parameter updates. However, existing ICRL methods rely on explicit reward signals during pretraining, which limits their applicability when rewards are ambiguous, hard to specify, or costly to obtain. To overcome this limitation, we propose a new learning paradigm, In-Context Preference-based Reinforcement Learning (ICPRL), in which both pretraining and deployment rely solely on preference feedback, eliminating the need for reward supervision. We study two variants that differ in the granularity of feedback: Immediate Preference-based RL (I-PRL) with per-step preferences, and Trajectory Preference-based RL (T-PRL) with trajectory-level comparisons. We first show that supervised pretraining, a standard approach in ICRL, remains effective under preference-only context datasets, demonstrating the feasibility of in-context reinforcement learning using only preference signals. To further improve data efficiency, we introduce alternative preference-native frameworks for I-PRL and T-PRL that directly optimize TM policies from preference data without requiring reward signals nor optimal action labels.Experiments on dueling bandits, navigation, and continuous control tasks demonstrate that ICPRL enables strong in-context generalization to unseen tasks, achieving performance comparable to ICRL methods trained with full reward supervision.
[871] Constraint-Aware Generative Auto-bidding via Pareto-Prioritized Regret Optimization
Binglin Wu, Yingyi Zhang, Xianneng Li, Ruyue Deng, Chuan Yue, Weiru Zhang, Xiaoyi Zeng
Main category: cs.LG
TL;DR: PRO-Bid: A constraint-aware generative auto-bidding framework using Constraint-Decoupled Pareto Representation and Counterfactual Regret Optimization to optimize marketing value while satisfying Target CPA constraints.
Details
Motivation: Auto-bidding systems need to maximize marketing value while satisfying strict efficiency constraints like Target CPA. Standard Decision Transformers face challenges: 1) Return-to-Go conditioning causes state aliasing by neglecting cost dimension, preventing precise resource pacing; 2) Regression forces policy to mimic average historical behaviors, limiting optimization toward constraint boundaries.Method: PRO-Bid introduces two synergistic mechanisms: 1) Constraint-Decoupled Pareto Representation (CDPR) decomposes global constraints into recursive cost and value contexts to restore resource perception, while reweighting trajectories based on Pareto frontier to focus on high-efficiency data; 2) Counterfactual Regret Optimization (CRO) uses a global outcome predictor to identify superior counterfactual actions, treating high-utility outcomes as weighted regression targets to approach optimal constraint boundaries.
Result: Extensive experiments on two public benchmarks and online A/B tests demonstrate that PRO-Bid achieves superior constraint satisfaction and value acquisition compared to state-of-the-art baselines.
Conclusion: PRO-Bid effectively addresses the limitations of standard Decision Transformers in constrained auto-bidding settings by combining constraint-aware representation learning with counterfactual optimization, enabling better resource pacing and performance optimization toward constraint boundaries.
Abstract: Auto-bidding systems aim to maximize marketing value while satisfying strict efficiency constraints such as Target Cost-Per-Action (CPA). Although Decision Transformers provide powerful sequence modeling capabilities, applying them to this constrained setting encounters two challenges: 1) standard Return-to-Go conditioning causes state aliasing by neglecting the cost dimension, preventing precise resource pacing; and 2) standard regression forces the policy to mimic average historical behaviors, thereby limiting the capacity to optimize performance toward the constraint boundary. To address these challenges, we propose PRO-Bid, a constraint-aware generative auto-bidding framework based on two synergistic mechanisms: 1) Constraint-Decoupled Pareto Representation (CDPR) decomposes global constraints into recursive cost and value contexts to restore resource perception, while reweighting trajectories based on the Pareto frontier to focus on high-efficiency data; and 2) Counterfactual Regret Optimization (CRO) facilitates active improvement by utilizing a global outcome predictor to identify superior counterfactual actions. By treating these high-utility outcomes as weighted regression targets, the model transcends historical averages to approach the optimal constraint boundary. Extensive experiments on two public benchmarks and online A/B tests demonstrate that PRO-Bid achieves superior constraint satisfaction and value acquisition compared to state-of-the-art baselines.
[872] Inverting Data Transformations via Diffusion Sampling
Jinwoo Kim, Sékou-Oumar Kaba, Jiyun Park, Seunghoon Hong, Siamak Ravanbakhsh
Main category: cs.LG
TL;DR: TIED is a method for inverting unknown transformations on Lie groups using diffusion processes, with applications to improving neural network robustness through test-time equivariance.
Details
Motivation: Unknown transformations in data observations can significantly distort machine learning models. The paper aims to recover inverse transformations that map transformed data back to the original distribution, particularly to improve robustness of pretrained networks.Method: Proposes Transformation-Inverting Energy Diffusion (TIED) - a diffusion process on Lie groups that keeps updates on-manifold using computations in the associated Lie algebra. Uses a new trivialized target-score identity for efficient score-based sampling of transformation posteriors.
Result: Experiments on image homographies and PDE symmetries show TIED can restore transformed inputs to training distribution at test time, outperforming canonicalization and sampling baselines.
Conclusion: TIED provides an effective probabilistic approach for transformation inversion on Lie groups, enabling improved test-time equivariance for neural networks.
Abstract: We study the problem of transformation inversion on general Lie groups: a datum is transformed by an unknown group element, and the goal is to recover an inverse transformation that maps it back to the original data distribution. Such unknown transformations arise widely in machine learning and scientific modeling, where they can significantly distort observations. We take a probabilistic view and model the posterior over transformations as a Boltzmann distribution defined by an energy function on data space. To sample from this posterior, we introduce a diffusion process on Lie groups that keeps all updates on-manifold and only requires computations in the associated Lie algebra. Our method, Transformation-Inverting Energy Diffusion (TIED), relies on a new trivialized target-score identity that enables efficient score-based sampling of the transformation posterior. As a key application, we focus on test-time equivariance, where the objective is to improve the robustness of pretrained neural networks to input transformations. Experiments on image homographies and PDE symmetries demonstrate that TIED can restore transformed inputs to the training distribution at test time, showing improved performance over strong canonicalization and sampling baselines. Code is available at https://github.com/jw9730/tied.
[873] When Do Multi-Agent Systems Outperform? Analysing the Learning Efficiency of Agentic Systems
Junwei Su, Chuan Wu
Main category: cs.LG
TL;DR: Theoretical analysis comparing multi-agent vs single-agent reinforcement learning for LLMs, showing MARL improves sample efficiency when tasks decompose into independent subtasks but loses advantage with dependent subtasks.
Details
Motivation: While MARL shows promise for training LLMs by decomposing complex tasks into specialized subtasks, there's limited theoretical understanding of when and why MARL outperforms single-agent RL, creating uncertainty in framework selection for LLM applications.Method: Uses the Probably Approximately Correct (PAC) framework to formally define SARL and MARL setups for LLMs, derive explicit sample complexity bounds, and systematically analyze how task decomposition and alignment influence learning efficiency.
Result: MARL improves sample complexity when tasks naturally decompose into independent subtasks, but dependent subtasks diminish MARL’s comparative advantage. Introduces task alignment concept to quantify trade-offs when enforcing independent decomposition despite potential misalignments.
Conclusion: Provides theoretical insights clarifying empirical inconsistencies and practical criteria for deploying MARL strategies effectively in complex LLM scenarios, addressing the critical gap in understanding when MARL outperforms SARL for LLM training.
Abstract: Reinforcement Learning (RL) has emerged as a crucial method for training or fine-tuning large language models (LLMs), enabling adaptive, task-specific optimizations through interactive feedback. Multi-Agent Reinforcement Learning (MARL), in particular, offers a promising avenue by decomposing complex tasks into specialized subtasks learned by distinct interacting agents, potentially enhancing the ability and efficiency of LLM systems. However, theoretical insights regarding when and why MARL outperforms Single-Agent RL (SARL) remain limited, creating uncertainty in selecting the appropriate RL framework. In this paper, we address this critical gap by rigorously analyzing the comparative sample efficiency of MARL and SARL within the context of LLM. Leveraging the Probably Approximately Correct (PAC) framework, we formally define SARL and MARL setups for LLMs, derive explicit sample complexity bounds, and systematically characterize how task decomposition and alignment influence learning efficiency. Our results demonstrate that MARL improves sample complexity when tasks naturally decompose into independent subtasks, whereas dependent subtasks diminish MARL’s comparative advantage. Additionally, we introduce and analyze the concept of task alignment, quantifying the trade-offs when enforcing independent task decomposition despite potential misalignments. These theoretical insights clarify empirical inconsistencies and provide practical criteria for deploying MARL strategies effectively in complex LLM scenarios.
[874] Noise Stability of Transformer Models
Themistoklis Haris, Zihan Zhang, Yuichi Yoshida
Main category: cs.LG
TL;DR: The paper proposes noise stability as a better simplicity metric than average sensitivity for understanding deep learning models, develops theoretical analysis for attention and MLP layers, and shows practical benefits through regularization that accelerates training and catalyzes grokking.
Details
Motivation: Current simplicity metrics like average sensitivity have limitations: they don't generalize well to real-valued domains and fail to explain the "junta-like" input dependence observed in modern LLMs. There's a need for better metrics to understand model robustness and interpretability.Method: Proposes noise stability as a new simplicity metric measuring robustness to correlated noise across all inputs. Provides theoretical analysis for single-layer attention and ReLU MLP layers, and uses covariance interval propagation for multi-layer analysis. Develops a practical noise stability regularization method.
Result: Experiments on algorithmic and next-token-prediction tasks show the noise stability regularizer consistently catalyzes grokking and accelerates training by approximately 35% and 75% respectively.
Conclusion: Noise stability emerges as a powerful tool for understanding and improving modern Transformers, establishing a new connection between signal propagation in neural networks and interpretability.
Abstract: Understanding simplicity biases in deep learning offers a promising path toward developing reliable AI. A common metric for this, inspired by Boolean function analysis, is average sensitivity, which captures a model’s robustness to single-token perturbations. We argue that average sensitivity has two key limitations: it lacks a natural generalization to real-valued domains and fails to explain the “junta-like” input dependence we empirically observe in modern LLMs. To address these limitations, we propose noise stability as a more comprehensive simplicity metric. Noise stability expresses a model’s robustness to correlated noise applied to all input coordinates simultaneously. We provide a theoretical analysis of noise stability for single-layer attention and ReLU MLP layers and tackle the multi-layer propagation problem with a covariance interval propagation approach. Building on this theory, we develop a practical noise stability regularization method. Experiments on algorithmic and next-token-prediction tasks show that our regularizer consistently catalyzes grokking and accelerates training by approximately $35%$ and $75%$ respectively. Our results sculpt a new connection between signal propagation in neural networks and interpretability, with noise stability emerging as a powerful tool for understanding and improving modern Transformers.
[875] Trust-Based Incentive Mechanisms in Semi-Decentralized Federated Learning Systems
Ajay Kumar Shrestha
Main category: cs.LG
TL;DR: A trust-based incentive mechanism for federated learning that evaluates participant contributions using trust scores and integrates blockchain for automated, transparent reward distribution.
Details
Motivation: Federated learning faces challenges with malicious/faulty nodes degrading model performance; need mechanisms to ensure integrity, reliability, and encourage honest participation while penalizing bad actors.Method: Proposes dynamic trust scoring based on data quality, model accuracy, consistency, and contribution frequency; integrates blockchain and smart contracts to automate trust evaluation and incentive distribution.
Result: Theoretical framework for a more robust, fair, and transparent FL ecosystem that reduces risks from untrustworthy participants through automated trust-based incentives.
Conclusion: Trust-based incentive mechanisms with blockchain integration can create more secure and reliable federated learning systems by rewarding honest participation and penalizing malicious behavior.
Abstract: In federated learning (FL), decentralized model training allows multi-ple participants to collaboratively improve a shared machine learning model without exchanging raw data. However, ensuring the integrity and reliability of the system is challenging due to the presence of potentially malicious or faulty nodes that can degrade the model’s performance. This paper proposes a novel trust-based incentive mechanism designed to evaluate and reward the quality of contributions in FL systems. By dynamically assessing trust scores based on fac-tors such as data quality, model accuracy, consistency, and contribution fre-quency, the system encourages honest participation and penalizes unreliable or malicious behavior. These trust scores form the basis of an incentive mechanism that rewards high-trust nodes with greater participation opportunities and penal-ties for low-trust participants. We further explore the integration of blockchain technology and smart contracts to automate the trust evaluation and incentive distribution processes, ensuring transparency and decentralization. Our proposed theoretical framework aims to create a more robust, fair, and transparent FL eco-system, reducing the risks posed by untrustworthy participants.
[876] Grokking in Linear Models for Logistic Regression
Nataraj Das, Atreya Vedantam, Chandrashekar Lakshminarayanan
Main category: cs.LG
TL;DR: Grokking (delayed generalization) can occur even in simple linear models with logistic loss, not requiring deep networks, through gradient descent dynamics and data asymmetries.
Details
Motivation: The paper investigates whether grokking requires deep neural networks with compositional structure, by studying it in the simplest possible setting: linear models with logistic loss for binary classification.Method: Theoretical analysis of gradient descent dynamics on linearly separable data with logistic loss, examining three testing regimes: same distribution, margin-concentrated, and adversarial (PGD) test data. Experiments validate theory by planting different distributions of population points and support vectors.
Result: Grokking emerges in linear models through three-phase learning process: population-dominated, support-vector-dominated unlearning, and support-vector-dominated generalization. Grokking time relates to data asymmetries in class examples and support vector distributions.
Conclusion: Grokking doesn’t require depth or representation learning; it can emerge in linear models through gradient descent bias term dynamics and data distribution asymmetries.
Abstract: Grokking, the phenomenon of delayed generalization, is often attributed to the depth and compositional structure of deep neural networks. We study grokking in one of the simplest possible settings: the learning of a linear model with logistic loss for binary classification on data that are linearly (and max margin) separable about the origin. We investigate three testing regimes: (1) test data drawn from the same distribution as the training data, in which case grokking is not observed; (2) test data concentrated around the margin, in which case grokking is observed; and (3) adversarial test data generated via projected gradient descent (PGD) attacks, in which case grokking is also observed. We theoretically show that the implicit bias of gradient descent induces a three-phase learning process-population-dominated, support-vector-dominated unlearning, and support-vector-dominated generalization-during which delayed generalization can arise. Our analysis further relates the emergence of grokking to asymmetries in the data, both in the number of examples per class and in the distribution of support vectors across classes, and yields a characterization of the grokking time. We experimentally validate our theory by planting different distributions of population points and support vectors, and by analyzing accuracy curves and hyperplane dynamics. Overall, our results demonstrate that grokking does not require depth or representation learning, and can emerge even in linear models through the dynamics of the bias term.
[877] TextResNet: Decoupling and Routing Optimization Signals in Compound AI Systems via Deep Residual Tuning
Suizhi Huang, Mei Li, Han Yu, Xiaoxiao Li
Main category: cs.LG
TL;DR: TextResNet addresses the Semantic Entanglement problem in TextGrad optimizers for deep compound AI systems by introducing additive semantic deltas, semantic gradient decomposition, causal routing, and density-aware optimization scheduling.
Details
Motivation: Textual gradient-style optimizers (TextGrad) work poorly for deep chains in compound AI systems due to Semantic Entanglement, where feedback signals mix local critiques with upstream contexts, causing Attribution Ambiguity.Method: Four key innovations: 1) Additive Semantic Deltas in forward pass to preserve Identity Highway; 2) Semantic Gradient Decomposition via Semantic Projector to disentangle feedback; 3) Causal Routing to direct signals to specific components; 4) Density-Aware Optimization Scheduling to allocate resources to bottlenecks.
Result: TextResNet achieves superior performance compared to TextGrad and exhibits remarkable stability for agentic tasks in compound AI systems where baselines collapse.
Conclusion: TextResNet successfully addresses the Semantic Entanglement problem in deep compound AI systems, enabling precise signal routing and stable optimization for complex agentic tasks.
Abstract: Textual Gradient-style optimizers (TextGrad) enable gradient-like feedback propagation through compound AI systems. However, they do not work well for deep chains. The root cause of this limitation stems from the Semantic Entanglement problem in these extended workflows. In standard textual backpropagation, feedback signals mix local critiques with upstream contexts, leading to Attribution Ambiguity. To address this challenge, we propose TextResNet, a framework that reformulates the optimization process to achieve precise signal routing via four key innovations. Firstly, in the forward pass, it enforces Additive Semantic Deltas to preserve an Identity Highway for gradient flow. Secondly, in the backward pass, it introduces Semantic Gradient Decomposition via a Semantic Projector to disentangle feedback into causally independent subspaces. Thirdly, it implements Causal Routing, which routes projected signals to their specific components. Finally, it performs Density-Aware Optimization Scheduling to leverage the disentangled signals to dynamically allocate resources to key system bottlenecks. Our results show that TextResNet not only achieves superior performance compared to TextGrad, but also exhibits remarkable stability for agentic tasks in compound AI systems where baselines collapse. Code is available at https://github.com/JeanDiable/TextResNet.
[878] Interaction-Grounded Learning for Contextual Markov Decision Processes with Personalized Feedback
Mengxiao Zhang, Yuheng Zhang, Haipeng Luo, Paul Mineiro
Main category: cs.LG
TL;DR: Extends Interaction-Grounded Learning to sequential decision-making with multi-step MDPs, proposing an efficient algorithm for learning from indirect feedback in multi-turn interactions.
Details
Motivation: Prior IGL work focused on single-step settings, limiting applicability to modern sequential systems like multi-turn LLM deployments that need to learn from indirect feedback rather than explicit rewards.Method: Extends reward-estimator construction from single-step to multi-step MDPs, designs Inverse-Gap-Weighting algorithm for policy optimization, addresses challenges of decoding latent rewards under MDPs.
Result: Achieves sublinear regret guarantee for contextual episodic MDPs with personalized feedback, demonstrates effectiveness on synthetic episodic MDP and real-world user booking dataset.
Conclusion: Successfully bridges gap between single-step IGL and sequential decision-making, enabling learning personalized objectives from multi-turn interactions with indirect feedback.
Abstract: In this paper, we study Interaction-Grounded Learning (IGL) [Xie et al., 2021], a paradigm designed for realistic scenarios where the learner receives indirect feedback generated by an unknown mechanism, rather than explicit numerical rewards. While prior work on IGL provides efficient algorithms with provable guarantees, those results are confined to single-step settings, restricting their applicability to modern sequential decision-making systems such as multi-turn Large Language Model (LLM) deployments. To bridge this gap, we propose a computationally efficient algorithm that achieves a sublinear regret guarantee for contextual episodic Markov Decision Processes (MDPs) with personalized feedback. Technically, we extend the reward-estimator construction of Zhang et al. [2024a] from the single-step to the multi-step setting, addressing the unique challenges of decoding latent rewards under MDPs. Building on this estimator, we design an Inverse-Gap-Weighting (IGW) algorithm for policy optimization. Finally, we demonstrate the effectiveness of our method in learning personalized objectives from multi-turn interactions through experiments on both a synthetic episodic MDP and a real-world user booking dataset.
[879] Fast Flow Matching based Conditional Independence Tests for Causal Discovery
Shunyu Zhao, Yanfeng Yang, Shuai Li, Kenji Fukumizu
Main category: cs.LG
TL;DR: FMCIT is a flow matching-based conditional independence test that accelerates causal discovery by requiring only one model training throughout the entire process, with GPC-FMCIT framework providing explicit bounds on CI queries.
Details
Motivation: Constraint-based causal discovery methods suffer from high computational complexity due to numerous conditional independence tests needed, limiting practical applicability. There's a need to accelerate individual CI tests to make causal discovery more efficient.Method: Proposes Flow Matching-based Conditional Independence Test (FMCIT) that leverages computational efficiency of flow matching, requiring only one model training for entire causal discovery. Also develops GPC-FMCIT framework combining fast screening with guided, budgeted refinement using FMCIT.
Result: FMCIT effectively controls type-I error and maintains high testing power even with high-dimensional conditioning sets. GPC-FMCIT demonstrates favorable accuracy-efficiency trade-offs over existing CI testing methods and PC variants in synthetic and real-world tasks.
Conclusion: FMCIT and GPC-FMCIT provide efficient solutions for causal discovery by accelerating CI tests through flow matching and structured query budgeting, making constraint-based methods more practical for real-world applications.
Abstract: Constraint-based causal discovery methods require a large number of conditional independence (CI) tests, which severely limits their practical applicability due to high computational complexity. Therefore, it is crucial to design an algorithm that accelerates each individual test. To this end, we propose the Flow Matching-based Conditional Independence Test (FMCIT). The proposed test leverages the high computational efficiency of flow matching and requires the model to be trained only once throughout the entire causal discovery procedure, substantially accelerating causal discovery. According to numerical experiments, FMCIT effectively controls type-I error and maintains high testing power under the alternative hypothesis, even in the presence of high-dimensional conditioning sets. In addition, we further integrate FMCIT into a two-stage guided PC skeleton learning framework, termed GPC-FMCIT, which combines fast screening with guided, budgeted refinement using FMCIT. This design yields explicit bounds on the number of CI queries while maintaining high statistical power. Experiments on synthetic and real-world causal discovery tasks demonstrate favorable accuracy-efficiency trade-offs over existing CI testing methods and PC variants.
[880] Towards Efficient Large Language Reasoning Models via Extreme-Ratio Chain-of-Thought Compression
Yuntian Tang, Bohan Jia, Wenxuan Huang, Lianyue Zhang, Jiao Xie, Wenxi Li, Wei Li, Jie Hu, Xinghao Chen, Rongrong Ji, Shaohui Lin
Main category: cs.LG
TL;DR: Extra-CoT is a framework for extreme-ratio Chain-of-Thought compression that aggressively reduces token count while preserving reasoning accuracy through specialized compression training and hierarchical reinforcement learning.
Details
Motivation: Chain-of-Thought reasoning improves LLM performance but creates substantial computational overhead. Existing compression methods lose logical fidelity at high compression ratios, causing performance degradation. Need for high-fidelity, fast reasoning with minimal tokens.Method: 1) Train dedicated semantically-preserved compressor on mathematical CoT data with fine-grained annotations. 2) Fine-tune LLM on compressed pairs via mixed-ratio supervised fine-tuning to handle various compression budgets. 3) Apply Constrained and Hierarchical Ratio Policy Optimization (CHRPO) with hierarchical rewards to explicitly incentivize question-solving under lower budgets.
Result: On MATH-500 using Qwen3-1.7B, achieves over 73% token reduction with 0.6% accuracy improvement. Outperforms SOTA methods on three mathematical reasoning benchmarks.
Conclusion: Extra-CoT enables extreme compression of Chain-of-Thought reasoning while maintaining or improving accuracy, offering efficient inference for reasoning tasks.
Abstract: Chain-of-Thought (CoT) reasoning successfully enhances the reasoning capabilities of Large Language Models (LLMs), yet it incurs substantial computational overhead for inference. Existing CoT compression methods often suffer from a critical loss of logical fidelity at high compression ratios, resulting in significant performance degradation. To achieve high-fidelity, fast reasoning, we propose a novel EXTreme-RAtio Chain-of-Thought Compression framework, termed Extra-CoT, which aggressively reduces the token budget while preserving answer accuracy. To generate reliable, high-fidelity supervision, we first train a dedicated semantically-preserved compressor on mathematical CoT data with fine-grained annotations. An LLM is then fine-tuned on these compressed pairs via a mixed-ratio supervised fine-tuning (SFT), teaching it to follow a spectrum of compression budgets and providing a stable initialization for reinforcement learning (RL). We further propose Constrained and Hierarchical Ratio Policy Optimization (CHRPO) to explicitly incentivize question-solving ability under lower budgets by a hierarchical reward. Experiments on three mathematical reasoning benchmarks show the superiority of Extra-CoT. For example, on MATH-500 using Qwen3-1.7B, Extra-CoT achieves over 73% token reduction with an accuracy improvement of 0.6%, significantly outperforming state-of-the-art (SOTA) methods.
[881] Near-Oracle KV Selection via Pre-hoc Sparsity for Long-Context Inference
Yifei Gao, Lei Wang, Rong-Cheng Tu, Qixin Zhang, Jun Cheng, Dacheng Tao
Main category: cs.LG
TL;DR: PrHS: Pre-hoc Sparsity for LLM KV cache compression with explicit accuracy control via dropped mass bound, achieving 90%+ retrieval overhead reduction and 9.9x attention speedup.
Details
Motivation: Current sparse attention methods suffer from posterior bias - they rely on observed attention scores which distort true token importance and miss salient tokens, impairing long-range reasoning. Need KV cache compression with verifiable accuracy guarantees.Method: Proposes Pre-hoc Sparsity (PrHS) that selects KV entries BEFORE attention scoring. Derives theoretical bound on mutual-information loss based on dropped attention mass (delta). Instantiates three orthogonal pre-hoc selectors along time, depth, and layer dimensions.
Result: Reduces retrieval overhead by over 90%, achieves 3x higher retrieval sparsity than HShare at matched/better accuracy. Under 1% average degradation on LongBench, 15% lower attention FLOPs vs prior sparse baselines, 9.9x attention-operator latency speedup, 2.8x higher throughput on A100 GPUs.
Conclusion: PrHS provides verifiable accuracy guarantees for KV cache compression through pre-hoc selection with dropped mass control, significantly improving inference efficiency while maintaining quality.
Abstract: A core bottleneck in large language model (LLM) inference is the cost of attending over the ever-growing key-value (KV) cache. Although near-oracle top-k KV selection can preserve the quality of dense attention while sharply reducing computation and bandwidth, existing sparse methods generally rely on posterior heuristics, i.e., selectors conditioned on observed attention or proxy scores. Such conditioning introduces posterior bias: it tends to distort true token importance and miss salient tokens, thereby impairing long-range reasoning. To tackle this problem, we propose Pre-hoc Sparsity (PrHS), which selects KV entries before attention scoring and provides explicit accuracy control. Let the attention mass of discarded entries be delta (the dropped mass). Through a marginal-to-mutual-information analysis, we derive an upper bound on the mutual-information loss that depends only on the dropped mass. This relation explains failure modes of posterior heuristics and enables verifiable guarantees by controlling the dropped mass in advance. Within PrHS, we instantiate three orthogonal pre-hoc selectors along the axes of time, depth, and layer. Extensive experiments on LLaMA and Mistral families validate PrHS. Across GSM8K and CoQA, PrHS reduces retrieval overhead by over 90%, achieving 3x higher retrieval sparsity than HShare at matched or better accuracy. It incurs under 1% average degradation on LongBench, lowers attention FLOPs by about 15% versus prior sparse baselines, and yields a 9.9x speedup in attention-operator latency and 2.8x higher throughput on NVIDIA A100-80GB GPUs than the dense baseline.
[882] Regime Change Hypothesis: Foundations for Decoupled Dynamics in Neural Network Training
Cristian Pérez-Corral, Alberto Fernández-Hernández, Jose I. Mestre, Manuel F. Dolz, Jose Duato, Enrique S. Quintana-Ortí
Main category: cs.LG
TL;DR: Training dynamics of ReLU-based DNNs exhibit two timescales: early stage with frequent activation pattern changes, and later stage where weight updates refine models within stable activation regimes.
Details
Motivation: To better understand the internal training dynamics of deep neural networks, particularly ReLU-based models where activation patterns define piecewise-linear regions, and investigate whether training exhibits distinct temporal phases.Method: Prove local stability property for activation patterns, then empirically track per-iteration changes in weights and activation patterns across various architectures (fully-connected, convolutional, Transformers) using fixed validation subsets.
Result: Activation pattern changes decay 3 times earlier than weight update magnitudes, showing late-stage training occurs within relatively stable activation regimes across all evaluated settings.
Conclusion: Training exhibits two-timescale behavior, providing an architecture-agnostic instrument for monitoring training dynamics and motivating decoupled optimization strategies for piecewise-linear networks.
Abstract: Despite the empirical success of DNN, their internal training dynamics remain difficult to characterize. In ReLU-based models, the activation pattern induced by a given input determines the piecewise-linear region in which the network behaves affinely. Motivated by this geometry, we investigate whether training exhibits a two-timescale behavior: an early stage with substantial changes in activation patterns and a later stage where weight updates predominantly refine the model within largely stable activation regimes. We first prove a local stability property: outside measure-zero sets of parameters and inputs, sufficiently small parameter perturbations preserve the activation pattern of a fixed input, implying locally affine behavior within activation regions. We then empirically track per-iteration changes in weights and activation patterns across fully-connected and convolutional architectures, as well as Transformer-based models, where activation patterns are recorded in the ReLU feed-forward (MLP/FFN) submodules, using fixed validation subsets. Across the evaluated settings, activation-pattern changes decay 3 times earlier than weight-update magnitudes, showing that late-stage training often proceeds within relatively stable activation regimes. These findings provide a concrete, architecture-agnostic instrument for monitoring training dynamics and motivate further study of decoupled optimization strategies for piecewise-linear networks. For reproducibility, code and experiment configurations will be released upon acceptance.
[883] All ERMs Can Fail in Stochastic Convex Optimization Lower Bounds in Linear Dimension
Tal Burla, Roi Livni
Main category: cs.LG
TL;DR: The paper studies sample complexity of Empirical Risk Minimizers in stochastic convex optimization, showing cases where ERMs overfit despite learning being possible, and provides novel generalization lower bounds for Gradient Descent.
Details
Motivation: The motivation is to understand the sample complexity and generalization behavior of Empirical Risk Minimizers (ERMs) in stochastic convex optimization, particularly addressing open questions about when ERMs overfit even when learning is theoretically possible.Method: The authors construct specific instances in stochastic convex optimization to demonstrate that ERMs can overfit with linear sample complexity in dimension. They then extend this analysis to Gradient Descent, deriving generalization lower bounds through mathematical constructions and analysis of the optimization dynamics.
Result: The paper shows: 1) There exist instances where sample size is linear in dimension, learning is possible, but the ERM is likely unique and overfits, resolving Feldman’s open question. 2) A novel generalization lower bound of Ω(√(ηT/m¹·⁵)) for Gradient Descent, significantly narrowing the gap between existing upper and lower bounds.
Conclusion: ERMs can overfit even in convex settings with linear sample complexity, and Gradient Descent has fundamental generalization limitations that scale with learning rate and horizon relative to sample size, providing important theoretical insights into optimization algorithms’ generalization behavior.
Abstract: We study the sample complexity of the best-case Empirical Risk Minimizer in the setting of stochastic convex optimization. We show that there exists an instance in which the sample size is linear in the dimension, learning is possible, but the Empirical Risk Minimizer is likely to be unique and to overfit. This resolves an open question by Feldman. We also extend this to approximate ERMs. Building on our construction we also show that (constrained) Gradient Descent potentially overfits when horizon and learning rate grow w.r.t sample size. Specifically we provide a novel generalization lower bound of $Ω\left(\sqrt{ηT/m^{1.5}}\right)$ for Gradient Descent, where $η$ is the learning rate, $T$ is the horizon and $m$ is the sample size. This narrows down, exponentially, the gap between the best known upper bound of $O(ηT/m)$ and existing lower bounds from previous constructions.
[884] The Chicken and Egg Dilemma: Co-optimizing Data and Model Configurations for LLMs
Zhiliang Chen, Alfred Wei Lun Leong, Shao Yong Ong, Apivich Hemachandram, Gregory Kang Ruey Lau, Chuan-Sheng Foo, Zhengyuan Liu, Nancy F. Chen, Bryan Kian Hsiang Low
Main category: cs.LG
TL;DR: JoBS: A method for jointly optimizing LLM training data and model configurations using scaling-law-inspired performance predictors with Bayesian optimization
Details
Motivation: Training LLMs involves a chicken-and-egg dilemma where optimal data configurations depend on model configurations and vice versa, but existing methods optimize either data or model separately without considering their interaction.Method: JoBS uses a scaling-law-inspired performance predictor to aid Bayesian optimization. It allocates part of the budget to learn a predictor that estimates performance from few training steps, then uses BO with the predictor to amortize full-training costs.
Result: JoBS outperforms existing multi-fidelity BO baselines and separate data/model optimization approaches across diverse LLM tasks under the same optimization budget.
Conclusion: Joint optimization of data and model configurations is tractable and beneficial, with JoBS providing an efficient approach that amortizes training costs through predictive modeling.
Abstract: Co-optimizing data and model configurations for training LLMs presents a classic chicken-and-egg dilemma: The best training data configuration (e.g., data mixture) for a downstream task depends on the chosen model configuration (e.g., model architecture), and vice versa. However, jointly optimizing both data and model configurations is often deemed intractable, and existing methods focus on either data or model optimization without considering their interaction. We introduce JoBS, an approach that uses a scaling-law-inspired performance predictor to aid Bayesian optimization (BO) in jointly optimizing LLM training data and model configurations efficiently. JoBS allocates a portion of the optimization budget to learn an LLM performance predictor that predicts how promising a training configuration is from a small number of training steps. The remaining budget is used to perform BO entirely with the predictor, effectively amortizing the cost of running full-training runs. We study JoBS’s average regret and devise the optimal budget allocation to minimize regret. JoBS outperforms existing multi-fidelity BO baselines, as well as data and model optimization approaches across diverse LLM tasks under the same optimization budget.
[885] Dynamic Regret via Discounted-to-Dynamic Reduction with Applications to Curved Losses and Adam Optimizer
Yan-Feng Xie, Yu-Jie Zhang, Peng Zhao, Zhi-Hua Zhou
Main category: cs.LG
TL;DR: Dynamic regret analysis for FTRL methods in non-stationary online learning, with applications to curved losses (linear/logistic regression) and Adam optimizers.
Details
Motivation: Existing dynamic regret analyses for Follow-the-Regularized-Leader (FTRL) methods are limited, despite FTRL's importance for curved losses and understanding adaptive optimizers like Adam. The paper aims to address this gap.Method: Uses discounted-to-dynamic reduction to create a modular framework for deriving dynamic regret bounds for FTRL-related problems. Focuses on linear and logistic regression as representative curved losses, then extends to analyze Adam optimizers.
Result: Simplifies existing proofs for optimal dynamic regret of online linear regression, provides new dynamic regret guarantees for online logistic regression, obtains optimal convergence rates for Adam in stochastic/non-convex/non-smooth settings, and enables detailed analysis of Adam with two discount parameters.
Conclusion: The discounted-to-dynamic reduction provides a powerful modular approach for analyzing FTRL methods and Adam optimizers, yielding both simplified proofs and new theoretical guarantees for dynamic regret minimization in non-stationary environments.
Abstract: We study dynamic regret minimization in non-stationary online learning, with a primary focus on follow-the-regularized-leader (FTRL) methods. FTRL is important for curved losses and for understanding adaptive optimizers such as Adam, yet existing dynamic regret analyses are less explored for FTRL. To address this, we build on the discounted-to-dynamic reduction and present a modular way to obtain dynamic regret bounds of FTRL-related problems. Specifically, we focus on two representative curved losses: linear regression and logistic regression. Our method not only simplifies existing proofs for the optimal dynamic regret of online linear regression, but also yields new dynamic regret guarantees for online logistic regression. Beyond online convex optimization, we apply the reduction to analyze the Adam optimizers, obtaining optimal convergence rates in stochastic, non-convex, and non-smooth settings. The reduction also enables a more detailed treatment of Adam with two discount parameters $(β_1,β_2)$, leading to new results for both clipped and clip-free variants of Adam optimizers.
[886] OJBKQ: Objective-Joint Babai-Klein Quantization
Xinyu Wang, Ziyu Zhao, Peng Lu, Yu Gu, Xiao-Wen Chang
Main category: cs.LG
TL;DR: OJBKQ is a novel post-training quantization method for large language models that formulates weight quantization as a joint optimization problem over activations and weights, solving it using extended Babai-Klein algorithms to achieve better performance at 3-4 bits.
Details
Motivation: Existing weight-only PTQ methods rely on heuristic objectives and greedy rounding, leading to noticeable degradation under low-bit quantization. There's a need for more principled optimization approaches to maintain model quality during compression.Method: Formulates weight quantization as a joint optimization problem over activations and weights, resulting in a multiple-right-hand-side box-constrained integer least squares (BILS) problem. Uses extended Babai nearest-plane algorithm and extended Klein’s randomized Babai algorithm to find minimum-residual Babai-Klein points as sub-optimal solutions.
Result: OJBKQ achieves lower perplexity at 3-4 bits compared to existing PTQ approaches while maintaining comparable computational cost on large language models.
Conclusion: The proposed OJBKQ method provides a more principled approach to weight quantization that outperforms existing heuristic-based methods, offering better compression-performance trade-offs for large language models.
Abstract: Post-training quantization (PTQ) is widely used to compress large language models without retraining. However, many existing weight-only methods rely on heuristic objectives and greedy rounding, thus leading to noticeable degradation under low-bit quantization. In this work, we introduce OJBKQ (Objective-Joint Babai-Klein Quantization with K-Best Sampling), a layer-wise PTQ method that formulates weight quantization as a joint optimization problem over activations and weights. This formulation results in a multiple-right-hand-side box-constrained integer least squares (BILS) problem in each layer, which is NP-hard. For each column of the weight matrix, we apply an extended Babai nearest-plane algorithm and an extended version of Klein’s randomized Babai algorithm to find the minimum-residual Babai-Klein point, a sub-optimal solution to the BILS problem. Experimental results on large language models show that OJBKQ achieves lower perplexity at 3-4 bits compared to existing PTQ approaches, while maintaining comparable computational cost.
[887] Modalities, a PyTorch-native Framework For Large-scale LLM Training and Research
Max Lübbering, Timm Ruland, Richard Rutmann, Felix Stollenwerk, David Fitzek, Michael Fromm, Alexander Weber, Rafet Sifa, Nicolas Flores-Herr, Joachim Köhler, Mehdi Ali
Main category: cs.LG
TL;DR: Modalities is a PyTorch-native framework for LLM research that integrates efficient large-scale training with systematic ablation studies through modular design and declarative configuration.
Details
Motivation: Current LLM training frameworks lack proper tooling for large-scale ablation studies, forcing researchers to write custom wrappers and scripts despite substantial compute costs, leading to reproducibility and extensibility challenges.Method: Develops an end-to-end PyTorch-native framework that integrates state-of-the-art parallelization strategies for efficient pretraining and systematic ablations at scale, using modular design with declarative, self-contained configuration.
Result: Enables both efficient pretraining and systematic ablations at trillion-token and billion-parameter scale while providing reproducibility and extensibility levels difficult to achieve with existing LLM training frameworks.
Conclusion: Modalities addresses the gap in LLM research tooling by providing a comprehensive framework that supports both large-scale training and systematic ablation studies with improved reproducibility and extensibility.
Abstract: Today’s LLM (pre-) training and research workflows typically allocate a significant amount of compute to large-scale ablation studies. Despite the substantial compute costs of these ablations, existing open-source frameworks provide limited tooling for these experiments, often forcing researchers to write their own wrappers and scripts. We propose Modalities, an end-to-end PyTorch-native framework that integrates data-driven LLM research with large-scale model training from two angles. Firstly, by integrating state-of-the-art parallelization strategies, it enables both efficient pretraining and systematic ablations at trillion-token and billion-parameter scale. Secondly, Modalities adopts modular design with declarative, self-contained configuration, enabling reproducibility and extensibility levels that are difficult to achieve out-of-the-box with existing LLM training frameworks.
[888] Drop the mask! GAMM-A Taxonomy for Graph Attributes Missing Mechanisms
Richard Serrano, Baptiste Jeudy, Charlotte Laclau, Christine Largeron
Main category: cs.LG
TL;DR: Proposes GAMM framework extending missing data taxonomy to attributed graphs by linking missingness to both node attributes and graph structure, showing SOTA imputation methods struggle with graph-aware missingness.
Details
Motivation: Missing data in attributed graphs presents unique challenges beyond tabular datasets, requiring new frameworks that account for graph structure dependencies in missingness mechanisms.Method: Extends taxonomy for missing data mechanisms to attributed graphs via GAMM framework, systematically linking missingness probability to node attributes and graph structure, introducing graph-specific dependencies.
Result: Empirical demonstration shows state-of-the-art imputation methods, while effective on traditional masks, significantly struggle with more realistic graph-aware missingness scenarios.
Conclusion: Graph-aware missingness mechanisms require specialized approaches beyond traditional imputation methods, highlighting the need for frameworks like GAMM that account for structural dependencies in attributed graphs.
Abstract: Exploring missing data in attributed graphs introduces unique challenges beyond those found in tabular datasets. In this work, we extend the taxonomy for missing data mechanisms to attributed graphs by proposing GAMM (Graph Attributes Missing Mechanisms), a framework that systematically links missingness probability to both node attributes and the underlying graph structure. Our taxonomy enriches the conventional definitions of masking mechanisms by introducing graph-specific dependencies. We empirically demonstrate that state-of-the-art imputation methods, while effective on traditional masks, significantly struggle when confronted with these more realistic graph-aware missingness scenarios.
[889] Radial Müntz-Szász Networks: Neural Architectures with Learnable Power Bases for Multidimensional Singularities
Gnankan Landry Regis N’guessan, Bum Jun Kim
Main category: cs.LG
TL;DR: RMN introduces neural networks with learnable radial powers to model singular radial fields like 1/r and log r, achieving superior accuracy with far fewer parameters than MLPs and SIREN.
Details
Motivation: Radial singular fields (1/r, log r, crack-tip profiles) are difficult for coordinate-separable neural architectures. The paper establishes a fundamental obstruction: any C² radial and additively separable function must be quadratic, motivating specialized architectures for radial singularities.Method: Introduces Radial Müntz-Szász Networks (RMN) that represent fields as linear combinations of learnable radial powers r^μ (including negative exponents) with a limit-stable log-primitive for exact log r behavior. Extensions include RMN-Angular for angular dependence and RMN-MC for multiple sources with learnable centers.
Result: RMN achieves 1.5×-51× lower RMSE than MLPs and 10×-100× lower RMSE than SIREN while using only 27 parameters vs. 33,537 for MLPs and 8,577 for SIREN. Source-center recovery errors fall below 10^-4 when optimization converges.
Conclusion: RMN provides an efficient architecture for modeling radial singular fields with closed-form spatial gradients, enabling physics-informed learning on punctured domains. The paper also delineates RMN’s operating regime by reporting controlled failures on smooth, strongly non-radial targets.
Abstract: Radial singular fields, such as $1/r$, $\log r$, and crack-tip profiles, are difficult to model for coordinate-separable neural architectures. We show that any $C^2$ function that is both radial and additively separable must be quadratic, establishing a fundamental obstruction for coordinate-wise power-law models. Motivated by this result, we introduce Radial Müntz-Szász Networks (RMN), which represent fields as linear combinations of learnable radial powers $r^μ$, including negative exponents, together with a limit-stable log-primitive for exact $\log r$ behavior. RMN admits closed-form spatial gradients and Laplacians, enabling physics-informed learning on punctured domains. Across ten 2D and 3D benchmarks, RMN achieves 1.5$\times$–51$\times$ lower RMSE than MLPs and 10$\times$–100$\times$ lower RMSE than SIREN while using 27 parameters, compared with 33,537 for MLPs and 8,577 for SIREN. We extend RMN to angular dependence (RMN-Angular) and to multiple sources with learnable centers (RMN-MC); when optimization converges, source-center recovery errors fall below $10^{-4}$. We also report controlled failures on smooth, strongly non-radial targets to delineate RMN’s operating regime.
[890] The Connection between Kriging and Large Neural Networks
Marius Marinescu
Main category: cs.LG
TL;DR: Explores connections between Kriging/Gaussian process regression and neural networks, showing they are more related than they appear despite different theoretical foundations
Details
Motivation: As spatial statistics increasingly intertwines with AI, there's a need to understand the relationship between spatial statistics models (like Kriging) and machine learning models (like neural networks), which may appear unrelated at first glanceMethod: The paper studies connections between Kriging and neural networks, revisits relevant literature, and explores how combining both perspectives can enhance ML techniques
Result: The paper finds that Kriging and neural networks are strongly related despite their different theoretical foundations (probability theory vs black-box models)
Conclusion: Understanding the relations between spatial statistics and ML models can enhance ML techniques by making them more interpretable, reliable, and spatially aware
Abstract: AI has impacted many disciplines and is nowadays ubiquitous. In particular, spatial statistics is in a pivotal moment where it will increasingly intertwine with AI. In this scenario, a relevant question is what relationship spatial statistics models have with machine learning (ML) models, if any. In particular, in this paper, we explore the connections between Kriging and neural networks. At first glance, they may appear unrelated. Kriging - and its ML counterpart, Gaussian process regression - are grounded in probability theory and stochastic processes, whereas many ML models are extensively considered Black-Box models. Nevertheless, they are strongly related. We study their connections and revisit the relevant literature. The understanding of their relations and the combination of both perspectives may enhance ML techniques by making them more interpretable, reliable, and spatially aware.
[891] USBD: Universal Structural Basis Distillation for Source-Free Graph Domain Adaptation
Yingxu Wang, Kunyu Zhang, Mengzhu Wang, Siyang Gao, Nan Yin
Main category: cs.LG
TL;DR: USBD proposes a universal structural basis distillation framework for source-free graph domain adaptation that learns structure-agnostic prototypes covering diverse topological patterns, enabling adaptation to targets with significant structural shifts.
Details
Motivation: Current source-free graph domain adaptation methods rely on smoothness priors from source-trained GNNs, which fail when target graphs have significantly different topological structures. These methods misinterpret unseen topological patterns as noise, making pseudo-label-based adaptation unreliable under severe structural shifts.Method: USBD uses bi-level optimization to distill source dataset into compact structural basis prototypes that span the full Dirichlet energy spectrum, capturing diverse topological motifs (from low-frequency clusters to high-frequency chains). For inference, a spectral-aware ensemble mechanism dynamically activates optimal prototype combinations based on target graph’s spectral fingerprint.
Result: Extensive experiments show USBD significantly outperforms state-of-the-art methods, especially in scenarios with severe structural shifts, while achieving superior computational efficiency by decoupling adaptation cost from target data scale.
Conclusion: USBD shifts paradigm from adapting biased models to learning universal structural basis, enabling robust adaptation to structurally distinct targets without source data access, overcoming limitations of pseudo-label-based methods under topological shifts.
Abstract: SF-GDA is pivotal for privacy-preserving knowledge transfer across graph datasets. Although recent works incorporate structural information, they implicitly condition adaptation on the smoothness priors of sourcetrained GNNs, thereby limiting their generalization to structurally distinct targets. This dependency becomes a critical bottleneck under significant topological shifts, where the source model misinterprets distinct topological patterns unseen in the source domain as noise, rendering pseudo-label-based adaptation unreliable. To overcome this limitation, we propose the Universal Structural Basis Distillation, a framework that shifts the paradigm from adapting a biased model to learning a universal structural basis for SF-GDA. Instead of adapting a biased source model to a specific target, our core idea is to construct a structure-agnostic basis that proactively covers the full spectrum of potential topological patterns. Specifically, USBD employs a bi-level optimization framework to distill the source dataset into a compact structural basis. By enforcing the prototypes to span the full Dirichlet energy spectrum, the learned basis explicitly captures diverse topological motifs, ranging from low-frequency clusters to high-frequency chains, beyond those present in the source. This ensures that the learned basis creates a comprehensive structural covering capable of handling targets with disparate structures. For inference, we introduce a spectral-aware ensemble mechanism that dynamically activates the optimal prototype combination based on the spectral fingerprint of the target graph. Extensive experiments on benchmarks demonstrate that USBD significantly outperforms state-of-the-art methods, particularly in scenarios with severe structural shifts, while achieving superior computational efficiency by decoupling the adaptation cost from the target data scale.
[892] RIFLE: Robust Distillation-based FL for Deep Model Deployment on Resource-Constrained IoT Networks
Pouria Arefijamal, Mahdi Ahmadlou, Bardia Safaei, Jörg Henkel
Main category: cs.LG
TL;DR: RIFLE: A robust federated learning framework using knowledge distillation instead of gradient sharing, enabling deep model training on IoT devices while improving security and privacy.
Details
Motivation: Federated learning in IoT faces challenges with data heterogeneity, task complexity, and security vulnerabilities. TinyML models struggle with complex patterns under non-IID conditions, and conventional gradient sharing is vulnerable to malicious attacks while being computationally expensive for deep models on resource-constrained devices.Method: RIFLE replaces gradient sharing with logit-based knowledge transfer using a knowledge distillation aggregation scheme. It enables training of deep models (VGG-19, ResNet18) on IoT devices and includes a KL divergence-based validation mechanism to quantify client update reliability without exposing raw data.
Result: On MNIST, CIFAR-10, and CIFAR-100 under heterogeneous non-IID conditions: reduces false-positive detections by up to 87.5%, enhances poisoning attack mitigation by 62.5%, achieves up to 28.3% higher accuracy than conventional FL baselines within 10 rounds. Reduces VGG19 training time from over 600 days to 1.39 hours on typical IoT devices (0.3 GFLOPS).
Conclusion: RIFLE makes deep learning practical in resource-constrained IoT networks by combining knowledge distillation with robust validation mechanisms, addressing both computational constraints and security vulnerabilities in federated learning.
Abstract: Federated learning (FL) is a decentralized learning paradigm widely adopted in resource-constrained Internet of Things (IoT) environments. These devices, typically relying on TinyML models, collaboratively train global models by sharing gradients with a central server while preserving data privacy. However, as data heterogeneity and task complexity increase, TinyML models often become insufficient to capture intricate patterns, especially under extreme non-IID (non-independent and identically distributed) conditions. Moreover, ensuring robustness against malicious clients and poisoned updates remains a major challenge. Accordingly, this paper introduces RIFLE - a Robust, distillation-based Federated Learning framework that replaces gradient sharing with logit-based knowledge transfer. By leveraging a knowledge distillation aggregation scheme, RIFLE enables the training of deep models such as VGG-19 and Resnet18 within constrained IoT systems. Furthermore, a Kullback-Leibler (KL) divergence-based validation mechanism quantifies the reliability of client updates without exposing raw data, achieving high trust and privacy preservation simultaneously. Experiments on three benchmark datasets (MNIST, CIFAR-10, and CIFAR-100) under heterogeneous non-IID conditions demonstrate that RIFLE reduces false-positive detections by up to 87.5%, enhances poisoning attack mitigation by 62.5%, and achieves up to 28.3% higher accuracy compared to conventional federated learning baselines within only 10 rounds. Notably, RIFLE reduces VGG19 training time from over 600 days to just 1.39 hours on typical IoT devices (0.3 GFLOPS), making deep learning practical in resource-constrained networks.
[893] Estimating Aleatoric Uncertainty in the Causal Treatment Effect
Liyuan Xu, Bijan Mazaheri
Main category: cs.LG
TL;DR: Proposes variance of treatment effect (VTE) and conditional variance of treatment effect (CVTE) as measures of aleatoric uncertainty in causal inference, with nonparametric kernel-based estimators that work even with unobserved confounders.
Details
Motivation: Previous causal inference work focuses on average treatment effects but neglects variability and uncertainty in individual treatment responses. There's a need to quantify aleatoric uncertainty inherent in treatment effects.Method: Introduces VTE and CVTE as measures of aleatoric uncertainty. Proposes nonparametric kernel-based estimators for these quantities. Shows identifiability under mild assumptions even with unobserved confounders. Provides theoretical convergence analysis.
Result: Demonstrates superior or comparable performance to naive baselines on synthetic and semi-simulated datasets. Theoretical analysis establishes convergence of proposed estimators.
Conclusion: VTE and CVTE are identifiable measures of aleatoric uncertainty in treatment effects, and the proposed kernel-based estimators provide effective tools for quantifying this uncertainty even in the presence of unobserved confounders.
Abstract: Previous work on causal inference has primarily focused on averages and conditional averages of treatment effects, with significantly less attention on variability and uncertainty in individual treatment responses. In this paper, we introduce the variance of the treatment effect (VTE) and conditional variance of treatment effect (CVTE) as the natural measure of aleatoric uncertainty inherent in treatment responses, and we demonstrate that these quantities are identifiable from observed data under mild assumptions, even in the presence of unobserved confounders. We further propose nonparametric kernel-based estimators for VTE and CVTE, and our theoretical analysis establishes their convergence. We also test the performance of our method through extensive empirical experiments on both synthetic and semi-simulated datasets, where it demonstrates superior or comparable performance to naive baselines.
[894] Low Rank Transformer for Multivariate Time Series Anomaly Detection and Localization
Charalampos Shimillas, Kleanthis Malialis, Konstantinos Fokianos, Marios M. Polycarpou
Main category: cs.LG
TL;DR: ALoRa-T: A Transformer-based model with low-rank regularization for multivariate time series anomaly detection and localization, connecting Transformers to statistical time series methods.
Details
Motivation: Existing multivariate time series anomaly diagnosis methods lack theoretical insights, especially for anomaly localization which is critical but underexplored. The paper aims to bridge Transformers with statistical time series methods for better theoretical understanding and practical performance.Method: Proposes Attention Low-Rank Transformer (ALoRa-T) with low-rank regularization on self-attention, introduces Attention Low-Rank score to capture temporal anomaly characteristics, and develops ALoRa-Loc for anomaly localization by quantifying interrelationships among time series variables.
Result: Extensive experiments show the proposed methodology significantly outperforms state-of-the-art methods in both anomaly detection and localization tasks.
Conclusion: The paper provides theoretical insights connecting Transformers to statistical time series methods and demonstrates practical superiority in multivariate time series anomaly diagnosis through the ALoRa framework.
Abstract: Multivariate time series (MTS) anomaly diagnosis, which encompasses both anomaly detection and localization, is critical for the safety and reliability of complex, large-scale real-world systems. The vast majority of existing anomaly diagnosis methods offer limited theoretical insights, especially for anomaly localization, which is a vital but largely unexplored area. The aim of this contribution is to study the learning process of a Transformer when applied to MTS by revealing connections to statistical time series methods. Based on these theoretical insights, we propose the Attention Low-Rank Transformer (ALoRa-T) model, which applies low-rank regularization to self-attention, and we introduce the Attention Low-Rank score, effectively capturing the temporal characteristics of anomalies. Finally, to enable anomaly localization, we propose the ALoRa-Loc method, a novel approach that associates anomalies to specific variables by quantifying interrelationships among time series. Extensive experiments and real data analysis, show that the proposed methodology significantly outperforms state-of-the-art methods in both detection and localization tasks.
[895] Learning Credal Ensembles via Distributionally Robust Optimization
Kaizheng Wang, Ghifari Adam Faza, Fabio Cuzzolin, Siu Lun Chau, David Moens, Hans Hallez
Main category: cs.LG
TL;DR: CreDRO is a credal predictor that captures epistemic uncertainty from both training randomness and potential distribution shifts by learning an ensemble through distributionally robust optimization.
Details
Motivation: Current credal predictors mainly quantify epistemic uncertainty as disagreement from random training initializations, which reflects optimization sensitivity rather than deeper uncertainty sources. There's a need to capture uncertainty from potential distribution shifts between training and test data.Method: Proposes CreDRO which defines epistemic uncertainty as disagreement among models trained with varying relaxations of the i.i.d. assumption. Uses distributionally robust optimization to learn an ensemble of plausible models that capture uncertainty from both training randomness and potential distribution shifts.
Result: CreDRO consistently outperforms existing credal methods on out-of-distribution detection across multiple benchmarks and selective classification in medical applications.
Conclusion: CreDRO provides a more comprehensive approach to quantifying epistemic uncertainty by capturing both optimization randomness and meaningful disagreement from potential distribution shifts, leading to improved model robustness.
Abstract: Credal predictors are models that are aware of epistemic uncertainty and produce a convex set of probabilistic predictions. They offer a principled way to quantify predictive epistemic uncertainty (EU) and have been shown to improve model robustness in various settings. However, most state-of-the-art methods mainly define EU as disagreement caused by random training initializations, which mostly reflects sensitivity to optimization randomness rather than uncertainty from deeper sources. To address this, we define EU as disagreement among models trained with varying relaxations of the i.i.d. assumption between training and test data. Based on this idea, we propose CreDRO, which learns an ensemble of plausible models through distributionally robust optimization. As a result, CreDRO captures EU not only from training randomness but also from meaningful disagreement due to potential distribution shifts between training and test data. Empirical results show that CreDRO consistently outperforms existing credal methods on tasks such as out-of-distribution detection across multiple benchmarks and selective classification in medical applications.
[896] Time-Delayed Transformers for Data-Driven Modeling of Low-Dimensional Dynamics
Albert Alcalde, Markus Widhalm, Emre Yılmaz
Main category: cs.LG
TL;DR: A simplified transformer architecture called time-delayed transformer (TD-TF) is proposed for modeling unsteady spatio-temporal dynamics, bridging linear operator methods and deep sequence models with linear computational complexity.
Details
Motivation: To create a data-driven modeling approach for unsteady spatio-temporal dynamics that combines the interpretability and efficiency of linear operator-based methods (like time-delayed dynamic mode decomposition) with the expressive power of deep sequence models, while maintaining computational efficiency.Method: TD-TF uses a deliberately minimal transformer architecture: single self-attention layer with single query per prediction, single feedforward layer. This design allows interpretation as nonlinear generalization of time-delayed DMD while maintaining linear computational complexity in sequence length.
Result: TD-TF matches linear baseline performance on near-linear systems while significantly outperforming them in nonlinear/chaotic regimes. Validated on synthetic signals, unsteady aerodynamics, Lorenz ‘63 system, and reaction-diffusion model, showing accurate long-term dynamics capture.
Conclusion: TD-TF successfully bridges linear operator methods and deep sequence models, preserving interpretability and efficiency of linear models while providing enhanced expressive power for complex dynamics through minimal transformer architecture.
Abstract: We propose the time-delayed transformer (TD-TF), a simplified transformer architecture for data-driven modeling of unsteady spatio-temporal dynamics. TD-TF bridges linear operator-based methods and deep sequence models by showing that a single-layer, single-head transformer can be interpreted as a nonlinear generalization of time-delayed dynamic mode decomposition (TD-DMD). The architecture is deliberately minimal, consisting of one self-attention layer with a single query per prediction and one feedforward layer, resulting in linear computational complexity in sequence length and a small parameter count. Numerical experiments demonstrate that TD-TF matches the performance of strong linear baselines on near-linear systems, while significantly outperforming them in nonlinear and chaotic regimes, where it accurately captures long-term dynamics. Validation studies on synthetic signals, unsteady aerodynamics, the Lorenz ‘63 system, and a reaction-diffusion model show that TD-TF preserves the interpretability and efficiency of linear models while providing substantially enhanced expressive power for complex dynamics.
[897] Contextual Rollout Bandits for Reinforcement Learning with Verifiable Rewards
Xiaodong Lu, Xiaohan Wang, Jiajun Chai, Guojun Yin, Wei Lin, Zhijun Chen, Yu Luo, Fuzhen Zhuang, Yikun Ban, Deqing Wang
Main category: cs.LG
TL;DR: RLVR with neural scheduling framework for adaptive rollout selection improves reasoning in LLMs
Details
Motivation: Existing RLVR methods use rollouts indiscriminately with short horizons, treating heterogeneous quality responses uniformly and discarding historical rollouts after single use, leading to noisy supervision, poor sample efficiency, and suboptimal policy updates.Method: Formulate rollout scheduling in RLVR as contextual bandit problem; propose unified neural scheduling framework that adaptively selects high-value rollouts throughout training; treat each rollout as an arm with reward defined by induced performance gain between consecutive optimization steps; supports noise-aware intra-group selection and adaptive global reuse of historical rollouts.
Result: Experiments on six mathematical reasoning benchmarks demonstrate consistent gains in performance and training efficiency across multiple RLVR optimization methods.
Conclusion: The proposed neural scheduling framework effectively addresses limitations of existing RLVR methods, improving reasoning capabilities of large language models through better rollout utilization.
Abstract: Reinforcement Learning with Verifiable Rewards (RLVR) is an effective paradigm for improving the reasoning capabilities of large language models. However, existing RLVR methods utilize rollouts in an indiscriminate and short-horizon manner: responses of heterogeneous quality within each prompt are treated uniformly, and historical rollouts are discarded after a single use. This leads to noisy supervision, poor sample efficiency, and suboptimal policy updates. We address these issues by formulating rollout scheduling in RLVR as a contextual bandit problem and proposing a unified neural scheduling framework that adaptively selects high-value rollouts throughout training. Each rollout is treated as an arm whose reward is defined by the induced performance gain between consecutive optimization steps. The resulting scheduler supports both noise-aware intra-group selection and adaptive global reuse of historical rollouts within a single principled framework. We provide theoretical justification by deriving sublinear regret bounds and showing that enlarging the rollout buffer improves the achievable performance upper bound. Experiments on six mathematical reasoning benchmarks demonstrate consistent gains in performance and training efficiency across multiple RLVR optimization methods.
[898] Is Meta-Path Attention an Explanation? Evidence of Alignment and Decoupling in Heterogeneous GNNs
Maiqi Jiang, Noman Ali, Yiran Ding, Yanfu Zhang
Main category: cs.LG
TL;DR: MetaXplain: A meta-path-aware explanation protocol for heterogeneous graph neural networks that analyzes when meta-path attention reflects actual importance vs. when it decouples, using view-factorized explanations and schema-valid perturbations.
Details
Motivation: To empirically study whether meta-path attention in heterogeneous graph neural networks actually reflects meta-path importance, or when it can decouple from true importance, since most existing GNN explainers are designed for homogeneous graphs and naive adaptations can mix semantics.Method: Introduces MetaXplain, a meta-path-aware post-hoc explanation protocol that applies existing explainers in the meta-path view domain via: (1) view-factorized explanations, (2) schema-valid channel-wise perturbations, and (3) fusion-aware attribution, without modifying the underlying predictor. Benchmarks gradient-, perturbation-, and Shapley-style explainers on ACM, DBLP, and IMDB datasets with HAN and HAN-GCN models.
Result: Meta-path-aware explanations typically outperform random controls. The proposed Meta-Path Attention-Explanation Alignment (MP-AEA) metric reveals both high-alignment and statistically significant decoupling regimes depending on dataset and backbone. Retraining on explanation-induced subgraphs often preserves and sometimes improves predictive performance, suggesting an explanation-as-denoising effect.
Conclusion: Meta-path attention doesn’t always reflect true meta-path importance - it can decouple in certain regimes. The MetaXplain framework enables controlled analysis of this phenomenon, and explanation-based subgraph retraining can have denoising benefits.
Abstract: Meta-path-based heterogeneous graph neural networks aggregate over meta-path-induced views, and their semantic-level attention over meta-path channels is widely used as a narrative for ``which semantics matter.’’ We study this assumption empirically by asking: when does meta-path attention reflect meta-path importance, and when can it decouple? A key challenge is that most post-hoc GNN explainers are designed for homogeneous graphs, and naive adaptations to heterogeneous neighborhoods can mix semantics and confound perturbations. To enable a controlled empirical analysis, we introduce MetaXplain, a meta-path-aware post-hoc explanation protocol that applies existing explainers in the native meta-path view domain via (i) view-factorized explanations, (ii) schema-valid channel-wise perturbations, and (iii) fusion-aware attribution, without modifying the underlying predictor. We benchmark representative gradient-, perturbation-, and Shapley-style explainers on ACM, DBLP, and IMDB with HAN and HAN-GCN, comparing against xPath and type-matched random baselines under standard faithfulness metrics. To quantify attention reliability, we propose Meta-Path Attention–Explanation Alignment (MP-AEA), which measures rank correlation between learned attention weights and explanation-derived meta-path contribution scores across random runs. Our results show that meta-path-aware explanations typically outperform random controls, while MP-AEA reveals both high-alignment and statistically significant decoupling regimes depending on the dataset and backbone; moreover, retraining on explanation-induced subgraphs often preserves, and in some noisy regimes improves, predictive performance, suggesting an explanation-as-denoising effect.
[899] Bridging Academia and Industry: A Comprehensive Benchmark for Attributed Graph Clustering
Yunhui Liu, Pengyu Qiu, Yu Xing, Yongchao Liu, Peng Du, Chuntao Hong, Jiajun Zheng, Tao Zheng, Tieke He
Main category: cs.LG
TL;DR: PyAGC is a production-ready benchmark and library for Attributed Graph Clustering that addresses gaps between academic research and real-world deployment by providing scalable implementations and diverse datasets.
Details
Motivation: There's a significant gap between academic AGC research and real-world industrial deployment, with current evaluation protocols limited to small-scale, high-homophily citation datasets, non-scalable training paradigms, and reliance on supervised metrics that don't reflect label-scarce environments.Method: Presents PyAGC benchmark with: 1) Unified Encode-Cluster-Optimize framework for existing methodologies, 2) Memory-efficient mini-batch implementations of state-of-the-art AGC algorithms, 3) 12 diverse datasets (2.7K to 111M nodes) including industrial graphs with tabular features and low homophily, 4) Holistic evaluation protocol with unsupervised structural metrics and efficiency profiling.
Result: Battle-tested in high-stakes industrial workflows at Ant Group, providing a robust, reproducible, and scalable platform for AGC research. Code and resources are publicly available via GitHub, PyPI, and documentation.
Conclusion: PyAGC bridges the gap between academic AGC research and real-world deployment by offering comprehensive benchmarking, scalable implementations, and diverse datasets that reflect industrial needs, advancing the field toward realistic applications.
Abstract: Attributed Graph Clustering (AGC) is a fundamental unsupervised task that integrates structural topology and node attributes to uncover latent patterns in graph-structured data. Despite its significance in industrial applications such as fraud detection and user segmentation, a significant chasm persists between academic research and real-world deployment. Current evaluation protocols suffer from the small-scale, high-homophily citation datasets, non-scalable full-batch training paradigms, and a reliance on supervised metrics that fail to reflect performance in label-scarce environments. To bridge these gaps, we present PyAGC, a comprehensive, production-ready benchmark and library designed to stress-test AGC methods across diverse scales and structural properties. We unify existing methodologies into a modular Encode-Cluster-Optimize framework and, for the first time, provide memory-efficient, mini-batch implementations for a wide array of state-of-the-art AGC algorithms. Our benchmark curates 12 diverse datasets, ranging from 2.7K to 111M nodes, specifically incorporating industrial graphs with complex tabular features and low homophily. Furthermore, we advocate for a holistic evaluation protocol that mandates unsupervised structural metrics and efficiency profiling alongside traditional supervised metrics. Battle-tested in high-stakes industrial workflows at Ant Group, this benchmark offers the community a robust, reproducible, and scalable platform to advance AGC research towards realistic deployment. The code and resources are publicly available via GitHub (https://github.com/Cloudy1225/PyAGC), PyPI (https://pypi.org/project/pyagc), and Documentation (https://pyagc.readthedocs.io).
[900] Causal Schrödinger Bridges: Constrained Optimal Transport on Structural Manifolds
Rui Wu, Li YongJun
Main category: cs.LG
TL;DR: CSB reformulates counterfactual inference as Entropic Optimal Transport using diffusion processes to handle causal interventions across low-density regions, outperforming deterministic ODE approaches.
Details
Motivation: Deterministic ODE flows for generative modeling become brittle under causal interventions that require transporting probability mass across low-density regions where vector fields are ill-defined, leading to numerical instability and spurious correlations.Method: Introduces Causal Schrödinger Bridge (CSB) framework that uses diffusion processes (SDEs) instead of deterministic flows, leveraging Entropic Optimal Transport to robustly “tunnel” through support mismatches while enforcing structural admissibility constraints. Proves Structural Decomposition Theorem showing global high-dimensional bridge factorizes into local, robust transitions.
Result: Empirical validation on high-dimensional interventions (Morpho-MNIST) demonstrates CSB significantly outperforms deterministic baselines in structural consistency, particularly in regimes of strong, out-of-distribution treatments.
Conclusion: CSB provides a robust framework for counterfactual inference that handles causal interventions across low-density regions better than deterministic approaches, with theoretical guarantees via structural decomposition.
Abstract: Generative modeling typically seeks the path of least action via deterministic flows (ODE). While effective for in-distribution tasks, we argue that these deterministic paths become brittle under causal interventions, which often require transporting probability mass across low-density regions (“off-manifold”) where the vector field is ill-defined. This leads to numerical instability and spurious correlations. In this work, we introduce the Causal Schrödinger Bridge (CSB), a framework that reformulates counterfactual inference as Entropic Optimal Transport. Unlike deterministic approaches that require strict invertibility, CSB leverages diffusion processes (SDEs) to robustly “tunnel” through support mismatches while strictly enforcing structural admissibility constraints. We prove the Structural Decomposition Theorem, showing that the global high-dimensional bridge factorizes into local, robust transitions. Empirical validation on high-dimensional interventions (Morpho-MNIST) demonstrates that CSB significantly outperforms deterministic baselines in structural consistency, particularly in regimes of strong, out-of-distribution treatments.
[901] Stateless Yet Not Forgetful: Implicit Memory as a Hidden Channel in LLMs
Ahmed Salem, Andrew Paverd, Sahar Abdelnabi
Main category: cs.LG
TL;DR: LLMs can maintain persistent state across interactions through implicit memory in their outputs, enabling temporal backdoors called “time bombs” that activate after sequences of interactions rather than single triggers.
Details
Motivation: Challenge the assumption that LLMs are stateless and explore how they can maintain persistent information across independent interactions through their outputs, creating security vulnerabilities.Method: Introduce implicit memory concept and demonstrate temporal backdoors (time bombs) that can be induced through prompting or fine-tuning, showing how models can encode and recover state across interactions.
Result: Show that LLMs can maintain persistent state via implicit memory, creating security vulnerabilities like time bombs that activate after sequences of interactions, with implications for covert communication and manipulation.
Conclusion: Implicit memory creates new security and evaluation challenges for LLMs, requiring new stress-testing approaches to detect and control persistent state mechanisms across interactions.
Abstract: Large language models (LLMs) are commonly treated as stateless: once an interaction ends, no information is assumed to persist unless it is explicitly stored and re-supplied. We challenge this assumption by introducing implicit memory-the ability of a model to carry state across otherwise independent interactions by encoding information in its own outputs and later recovering it when those outputs are reintroduced as input. This mechanism does not require any explicit memory module, yet it creates a persistent information channel across inference requests. As a concrete demonstration, we introduce a new class of temporal backdoors, which we call time bombs. Unlike conventional backdoors that activate on a single trigger input, time bombs activate only after a sequence of interactions satisfies hidden conditions accumulated via implicit memory. We show that such behavior can be induced today through straightforward prompting or fine-tuning. Beyond this case study, we analyze broader implications of implicit memory, including covert inter-agent communication, benchmark contamination, targeted manipulation, and training-data poisoning. Finally, we discuss detection challenges and outline directions for stress-testing and evaluation, with the goal of anticipating and controlling future developments. To promote future research, we release code and data at: https://github.com/microsoft/implicitMemory.
[902] M-Loss: Quantifying Model Merging Compatibility with Limited Unlabeled Data
Tiantong Wang, Yiyang Duan, Haoyu Chen, Tiantong Wu, Wei Yang Bryan Lim
Main category: cs.LG
TL;DR: Proposes M-Loss, a novel metric to evaluate model merging compatibility by measuring discrepancy between parameter averaging and model ensembling, enabling better merging strategies with limited unlabeled data.
Details
Motivation: Large-scale model training is computationally intensive and data-constrained. Model merging offers an alternative but suffers from combining non-generalizable features, while ensembling has high inference costs. Need theoretical foundation and evaluation metrics for merging.Method: Introduces Merging-ensembling loss (M-Loss) that quantifies compatibility of merging source models using limited unlabeled data. Measures discrepancy between parameter averaging and model ensembling at layer and node levels to guide merging strategies.
Result: M-Loss improves alignment between merged models and model ensembling, serves as quantitative criterion for merging feasibility, and guides parameter significance in model pruning. Provides scalable framework for accurate model consolidation.
Conclusion: M-Loss bridges theoretical gap between model merging and ensembling, offering practical evaluation metric and guidance for effective model consolidation with limited data requirements.
Abstract: Training of large-scale models is both computationally intensive and often constrained by the availability of labeled data. Model merging offers a compelling alternative by directly integrating the weights of multiple source models without requiring additional data or extensive training. However, conventional model merging techniques, such as parameter averaging, often suffer from the unintended combination of non-generalizable features, especially when source models exhibit significant weight disparities. Comparatively, model ensembling generally provides more stable and superior performance that aggregates multiple models by averaging outputs. However, it incurs higher inference costs and increased storage requirements. While previous studies experimentally showed the similarities between model merging and ensembling, theoretical evidence and evaluation metrics remain lacking. To address this gap, we introduce Merging-ensembling loss (M-Loss), a novel evaluation metric that quantifies the compatibility of merging source models using very limited unlabeled data. By measuring the discrepancy between parameter averaging and model ensembling at layer and node levels, M-Loss facilitates more effective merging strategies. Specifically, M-Loss serves both as a quantitative criterion of the theoretical feasibility of model merging, and a guide for parameter significance in model pruning. Our theoretical analysis and empirical evaluations demonstrate that incorporating M-Loss into the merging process significantly improves the alignment between merged models and model ensembling, providing a scalable and efficient framework for accurate model consolidation.
[903] An arithmetic method algorithm optimizing k-nearest neighbors compared to regression algorithms and evaluated on real world data sources
Theodoros Anagnostopoulos, Evanthia Zervoudi, Christos Anagnostopoulos, Apostolos Christopoulos, Bogdan Wierzbinski
Main category: cs.LG
TL;DR: Proposes an Arithmetic Method Regression (AMR) algorithm that optimizes k-NN regression using an arithmetic method for solving linear equations with multiple variables.
Details
Motivation: To improve the performance of k-NN regression by leveraging a novel arithmetic method that can solve linear equations with arbitrary numbers of real variables, aiming to create a more efficient regression algorithm.Method: Introduces an Arithmetic Method Algorithm (AMA) for solving linear equations, then develops AMR as an optimization of k-NN that incorporates AMA’s capabilities. Compares AMR with other regression algorithms using an optimal inference decision rule on publicly available real-world datasets.
Result: AMR shows comparable performance to other regression algorithms and generally outperforms standard k-NN, demonstrating that AMR effectively optimizes the k-NN approach.
Conclusion: The proposed AMR algorithm successfully optimizes k-NN regression using the arithmetic method, showing promising results and improved performance over traditional k-NN in most cases.
Abstract: Linear regression analysis focuses on predicting a numeric regressand value based on certain regressor values. In this context, k-Nearest Neighbors (k-NN) is a common non-parametric regression algorithm, which achieves efficient performance when compared with other algorithms in literature. In this research effort an optimization of the k-NN algorithm is proposed by exploiting the potentiality of an introduced arithmetic method, which can provide solutions for linear equations involving an arbitrary number of real variables. Specifically, an Arithmetic Method Algorithm (AMA) is adopted to assess the efficiency of the introduced arithmetic method, while an Arithmetic Method Regression (AMR) algorithm is proposed as an optimization of k-NN adopting the potentiality of AMA. Such algorithm is compared with other regression algorithms, according to an introduced optimal inference decision rule, and evaluated on certain real world data sources, which are publicly available. Results are promising since the proposed AMR algorithm has comparable performance with the other algorithms, while in most cases it achieves better performance than the k-NN. The output results indicate that introduced AMR is an optimization of k-NN.
[904] Modeling Score Approximation Errors in Diffusion Models via Forward SPDEs
Junsu Seo
Main category: cs.LG
TL;DR: Theoretical analysis of Score-based Generative Models using SPDE framework to model probability density evolution under stochastic perturbations, with new evaluation metric based on quadratic variation.
Details
Motivation: To better understand the dynamics and robustness of Score-based Generative Models by moving beyond particle-centric SDE analyses and using an SPDE framework to model the evolution of probability density fields under stochastic perturbations.Method: Treats score estimation error as stochastic source driving Fokker-Planck equation, employs SPDE framework to model probability density evolution, analyzes robustness through geometric stability and displacement convexity, introduces evaluation metric based on quadratic variation of SPDE solution projected onto radial test function.
Result: Developed theoretical framework for analyzing SGMs, introduced candidate evaluation metric that appears effective using only initial 10% of sampling trajectory, suggesting potential for computational efficiency.
Conclusion: SPDE framework provides new perspective for analyzing SGMs, with promising evaluation metric that could enable more efficient assessment of generative model performance.
Abstract: This study investigates the dynamics of Score-based Generative Models (SGMs) by treating the score estimation error as a stochastic source driving the Fokker-Planck equation. Departing from particle-centric SDE analyses, we employ an SPDE framework to model the evolution of the probability density field under stochastic drift perturbations. Under a simplified setting, we utilize this framework to interpret the robustness of generative models through the lens of geometric stability and displacement convexity. Furthermore, we introduce a candidate evaluation metric derived from the quadratic variation of the SPDE solution projected onto a radial test function. Preliminary observations suggest that this metric remains effective using only the initial 10% of the sampling trajectory, indicating a potential for computational efficiency.
[905] Conditional Sequence Modeling for Safe Reinforcement Learning
Wensong Bai, Chao Zhang, Qihang Xu, Chufan Chen, Chenhao Zhou, Hui Qian
Main category: cs.LG
TL;DR: RCDT: A conditional sequence modeling approach for offline safe RL that enables zero-shot deployment across multiple cost thresholds with adaptive Lagrangian penalty and trajectory reweighting.
Details
Motivation: Existing offline safe RL methods are trained for specific cost thresholds, limiting generalization and deployment flexibility. Need for single policy that can adapt zero-shot to different cost thresholds in various scenarios.Method: RCDT combines conditional sequence modeling with Lagrangian-style cost penalty using auto-adaptive penalty coefficient. Includes reward-cost-aware trajectory reweighting mechanism and Q-value regularization to avoid conservative behavior.
Result: Extensive experiments on DSRL benchmark show RCDT consistently improves return-cost trade-offs over baselines, advancing state-of-the-art in offline safe RL.
Conclusion: RCDT enables flexible zero-shot deployment across cost thresholds within single policy, improving generalization and practical applicability of offline safe RL.
Abstract: Offline safe reinforcement learning (RL) aims to learn policies from a fixed dataset while maximizing performance under cumulative cost constraints. In practice, deployment requirements often vary across scenarios, necessitating a single policy that can adapt zero-shot to different cost thresholds. However, most existing offline safe RL methods are trained under a pre-specified threshold, yielding policies with limited generalization and deployment flexibility across cost thresholds. Motivated by recent progress in conditional sequence modeling (CSM), which enables flexible goal-conditioned control by specifying target returns, we propose RCDT, a CSM-based method that supports zero-shot deployment across multiple cost thresholds within a single trained policy. RCDT is the first CSM-based offline safe RL algorithm that integrates a Lagrangian-style cost penalty with an auto-adaptive penalty coefficient. To avoid overly conservative behavior and achieve a more favorable return–cost trade-off, a reward–cost-aware trajectory reweighting mechanism and Q-value regularization are further incorporated. Extensive experiments on the DSRL benchmark demonstrate that RCDT consistently improves return–cost trade-offs over representative baselines, advancing the state-of-the-art in offline safe RL.
[906] Predicting Future Utility: Global Combinatorial Optimization for Task-Agnostic KV Cache Eviction
Ziyao Tang, Pengkun Jiao, Xinhang Chen, Wei Liu, Shiyong Li, Jingjing Chen
Main category: cs.LG
TL;DR: LU-KV: A novel KV cache eviction framework that optimizes head-level budget allocation based on marginal utility of preserving long-term semantic information, achieving 80% KV cache reduction with minimal performance degradation.
Details
Motivation: Current KV cache eviction methods use instantaneous heuristic metrics that assume consistent importance across all attention heads, overlooking the heterogeneity in predictive fidelity where some heads prioritize instantaneous contributions while others capture long-horizon utility.Method: Proposes LU-KV framework with: 1) convex-hull relaxation for head-level budget allocation, 2) marginal-utility-based greedy solver for near-optimal precision, and 3) data-driven offline profiling protocol for practical deployment.
Result: Extensive evaluations on LongBench and RULER benchmarks show LU-KV achieves 80% reduction in KV cache size with minimal performance degradation, while reducing inference latency and GPU memory footprint.
Conclusion: Optimal KV cache eviction should be governed by marginal utility in preserving long-term semantic information, and LU-KV provides an effective framework for head-level budget allocation that significantly improves inference efficiency.
Abstract: Given the quadratic complexity of attention, KV cache eviction is vital to accelerate model inference. Current KV cache eviction methods typically rely on instantaneous heuristic metrics, implicitly assuming that score magnitudes are consistent proxies for importance across all heads. However, this overlooks the heterogeneity in predictive fidelity across attention heads. While certain heads prioritize the instantaneous contribution of tokens, others are dedicated to capturing long-horizon utility. In this paper, we propose that optimal budget allocation should be governed by the marginal utility in preserving long-term semantic information. Based on this insight, we propose LU-KV, a novel framework that optimizes head-level budget allocation through a convex-hull relaxation and a marginal-utility-based greedy solver to achieve near-optimal precision. Furthermore, we implement a data-driven offline profiling protocol to facilitate the practical deployment of LU-KV. Extensive evaluations on LongBench and RULER benchmarks demonstrate that LU-KV achieves an 80% reduction in KV cache size with minimal performance degradation, while simultaneously reducing inference latency and GPU memory footprint.
[907] FairRARI: A Plug and Play Framework for Fairness-Aware PageRank
Emmanouil Kariotakis, Aritra Konar
Main category: cs.LG
TL;DR: FairRARI: A convex optimization framework for computing PageRank vectors with group fairness constraints based on sensitive attributes of vertices in graphs.
Details
Motivation: Addressing algorithmic fairness in graph machine learning, specifically for PageRank computation, where existing methods lack principled approaches that guarantee target fairness levels while maintaining optimality.Method: Proposes FairRARI, a unified in-processing convex optimization framework using variational formulation of PageRank. Solves strongly convex optimization problems with fairness constraints in a “plug and play” fashion for different group-fairness criteria.
Result: FairRARI achieves desired fairness levels across multiple vertex groups while outperforming existing methods in utility. Maintains same asymptotic time-complexity as original PageRank algorithm.
Conclusion: FairRARI provides an effective, principled approach for fair PageRank computation with theoretical guarantees and practical efficiency, addressing fairness concerns in graph machine learning applications.
Abstract: PageRank (PR) is a fundamental algorithm in graph machine learning tasks. Owing to the increasing importance of algorithmic fairness, we consider the problem of computing PR vectors subject to various group-fairness criteria based on sensitive attributes of the vertices. At present, principled algorithms for this problem are lacking - some cannot guarantee that a target fairness level is achieved, while others do not feature optimality guarantees. In order to overcome these shortcomings, we put forth a unified in-processing convex optimization framework, termed FairRARI, for tackling different group-fairness criteria in a ``plug and play’’ fashion. Leveraging a variational formulation of PR, the framework computes fair PR vectors by solving a strongly convex optimization problem with fairness constraints, thereby ensuring that a target fairness level is achieved. We further introduce three different fairness criteria which can be efficiently tackled using FairRARI to compute fair PR vectors with the same asymptotic time-complexity as the original PR algorithm. Extensive experiments on real-world datasets showcase that FairRARI outperforms existing methods in terms of utility, while achieving the desired fairness levels across multiple vertex groups; thereby highlighting its effectiveness.
[908] SDFed: Bridging Local Global Discrepancy via Subspace Refinement and Divergence Control in Federated Prompt Learning
Yicheng Di, Wei Yuan, Tieke He, Zhanjie Zhang, Ao Ma, Yuan Liu, Hongzhi Yin
Main category: cs.LG
TL;DR: SDFed: A heterogeneous federated prompt learning framework for vision-language models that addresses client heterogeneity by allowing variable-length local prompts while maintaining fixed-length global prompts, with subspace refinement and divergence control to mitigate local-global conflicts.
Details
Motivation: Existing federated prompt learning approaches enforce unified prompt structures across clients, which is inadequate for practical client heterogeneity in data distributions and system resources, and may introduce conflicts between globally shared and locally optimal knowledge.Method: SDFed maintains a fixed-length global prompt for efficient aggregation while allowing each client to learn variable-length local prompts. It introduces subspace refinement for local prompts and an information retention and divergence control strategy to preserve key local information while maintaining appropriate separability between global and local representations.
Result: Extensive experiments on several datasets demonstrate that SDFed consistently improves performance and robustness in heterogeneous federated settings compared to existing approaches.
Conclusion: SDFed effectively addresses client heterogeneity in federated prompt learning for vision-language models by enabling flexible local prompt structures while maintaining efficient global aggregation and mitigating local-global conflicts through subspace refinement and divergence control.
Abstract: Vision-language pretrained models offer strong transferable representations, yet adapting them in privacy-sensitive multi-party settings is challenging due to the high communication cost of federated optimization and the limited local data on clients. Federated prompt learning mitigates this issue by keeping the VLPM backbone frozen and collaboratively training lightweight prompt parameters. However, existing approaches typically enforce a unified prompt structure and length across clients, which is inadequate under practical client heterogeneity in both data distributions and system resources, and may further introduce conflicts between globally shared and locally optimal knowledge. To address these challenges, we propose \textbf{SDFed}, a heterogeneous federated prompt learning framework that bridges Local-Global Discrepancy via Subspace Refinement and Divergence Control. SDFed maintains a fixed-length global prompt for efficient aggregation while allowing each client to learn a variable-length local prompt to better match its data characteristics and capacity. To mitigate local-global conflicts and facilitate effective knowledge transfer, SDFed introduces a subspace refinement method for local prompts and an information retention and divergence control strategy that preserves key local information while maintaining appropriate separability between global and local representations. Extensive experiments on several datasets demonstrate that SDFed consistently improves performance and robustness in heterogeneous federated settings.
[909] TFMLinker: Universal Link Predictor by Graph In-Context Learning with Tabular Foundation Models
Tianyin Liao, Chunyu Hu, Yicheng Sui, Xingxuan Zhang, Peng Cui, Jianxin Li, Ziwei Zhang
Main category: cs.LG
TL;DR: TFMLinker adapts tabular foundation models for universal link prediction across diverse graphs using in-context learning without dataset-specific fine-tuning.
Details
Motivation: Existing graph foundation models for link prediction have limitations in pre-training scale and heavy reliance on textual information. Tabular foundation models have shown success in universal prediction across diverse tabular datasets, motivating their adaptation for link prediction.Method: 1) Prototype-augmented local-global context module to construct context capturing graph-specific and cross-graph transferable patterns. 2) Universal topology-aware link encoder to capture link-centric topological information and generate link representations. 3) Use TFM for link prediction through in-context learning without dataset-specific fine-tuning.
Result: Experiments on 6 graph benchmarks across diverse domains demonstrate superiority over state-of-the-art baselines without requiring dataset-specific fine-tuning.
Conclusion: TFMLinker successfully adapts tabular foundation models for universal link prediction, leveraging their in-context learning capabilities to work across diverse graphs without dataset-specific training.
Abstract: Link prediction is a fundamental task in graph machine learning with widespread applications such as recommendation systems, drug discovery, knowledge graphs, etc. In the foundation model era, how to develop universal link prediction methods across datasets and domains becomes a key problem, with some initial attempts adopting Graph Foundation Models utilizing Graph Neural Networks and Large Language Models. However, the existing methods face notable limitations, including limited pre-training scale or heavy reliance on textual information. Motivated by the success of tabular foundation models (TFMs) in achieving universal prediction across diverse tabular datasets, we explore an alternative approach by TFMs, which are pre-trained on diverse synthetic datasets sampled from structural causal models and support strong in-context learning independent of textual attributes. Nevertheless, adapting TFMs for link prediction faces severe technical challenges such as how to obtain the necessary context and capture link-centric topological information. To solve these challenges, we propose TFMLinker (Tabular Foundation Model for Link Predictor), aiming to leverage the in-context learning capabilities of TFMs to perform link prediction across diverse graphs without requiring dataset-specific fine-tuning. Specifically, we first develop a prototype-augmented local-global context module to construct context that captures both graph-specific and cross-graph transferable patterns. Next, we design a universal topology-aware link encoder to capture link-centric topological information and generate link representations as inputs for the TFM. Finally, we employ the TFM to predict link existence through in-context learning. Experiments on 6 graph benchmarks across diverse domains demonstrate the superiority of our method over state-of-the-art baselines without requiring dataset-specific finetuning.
[910] Breaking the Grid: Distance-Guided Reinforcement Learning in Large Discrete and Hybrid Action Spaces
Heiko Hoppe, Fabian Akkerman, Wouter van Heeswijk, Maximilian Schiffer
Main category: cs.LG
TL;DR: DGRL enables efficient reinforcement learning in massive discrete action spaces (up to 10^20 actions) using semantic embeddings and distance-based updates, outperforming SOTA by up to 66%.
Details
Motivation: Standard RL algorithms struggle with the curse of dimensionality in large discrete action spaces common in logistics, scheduling, and recommender systems. Existing methods rely on restrictive grid structures or expensive nearest-neighbor searches, limiting effectiveness in high-dimensional or irregular domains.Method: Proposes Distance-Guided Reinforcement Learning (DGRL) with two key components: 1) Sampled Dynamic Neighborhoods (SDN) - uses semantic embedding space for stochastic volumetric exploration with full local trust region support, and 2) Distance-Based Updates (DBU) - transforms policy optimization into stable regression, decoupling gradient variance from action space size and ensuring monotonic improvement. Generalizes to hybrid continuous-discrete spaces without hierarchical dependencies.
Result: Achieves performance improvements of up to 66% against state-of-the-art benchmarks across both regularly and irregularly structured environments. Simultaneously improves convergence speed and computational complexity while handling spaces with up to 10^20 actions.
Conclusion: DGRL provides an effective solution for RL in massive discrete action spaces, overcoming limitations of previous methods through semantic embeddings and distance-based optimization. The approach is generalizable and computationally efficient.
Abstract: Reinforcement Learning is increasingly applied to logistics, scheduling, and recommender systems, but standard algorithms struggle with the curse of dimensionality in such large discrete action spaces. Existing algorithms typically rely on restrictive grid-based structures or computationally expensive nearest-neighbor searches, limiting their effectiveness in high-dimensional or irregularly structured domains. We propose Distance-Guided Reinforcement Learning (DGRL), combining Sampled Dynamic Neighborhoods (SDN) and Distance-Based Updates (DBU) to enable efficient RL in spaces with up to 10$^\text{20}$ actions. Unlike prior methods, SDN leverages a semantic embedding space to perform stochastic volumetric exploration, provably providing full support over a local trust region. Complementing this, DBU transforms policy optimization into a stable regression task, decoupling gradient variance from action space cardinality and guaranteeing monotonic policy improvement. DGRL naturally generalizes to hybrid continuous-discrete action spaces without requiring hierarchical dependencies. We demonstrate performance improvements of up to 66% against state-of-the-art benchmarks across regularly and irregularly structured environments, while simultaneously improving convergence speed and computational complexity.
[911] ERIS: Enhancing Privacy and Communication Efficiency in Serverless Federated Learning
Dario Fenoglio, Pasquale Polverino, Jacopo Quizi, Martin Gjoreski, Marc Langheinrich
Main category: cs.LG
TL;DR: ERIS: A serverless federated learning framework that balances privacy, accuracy, and communication efficiency for billion-parameter models through distributed aggregation and gradient compression.
Details
Motivation: Scaling federated learning to billion-parameter models creates trade-offs between communication efficiency, model accuracy, and privacy. Existing solutions address these challenges in isolation, often sacrificing accuracy or using costly cryptographic tools.Method: ERIS combines model partitioning with distributed client-side aggregators and a distributed shifted gradient compression mechanism. It eliminates the server bottleneck and distributes communication load while maintaining privacy.
Result: ERIS achieves FedAvg-level accuracy while substantially reducing communication costs and improving robustness to membership inference and reconstruction attacks, without heavy cryptography or noise injection.
Conclusion: ERIS provides a balanced solution for scaling federated learning to large models, offering strong privacy guarantees with no accuracy degradation through distributed aggregation and compression techniques.
Abstract: Scaling federated learning (FL) to billion-parameter models introduces critical trade-offs between communication efficiency, model accuracy, and privacy guarantees. Existing solutions often tackle these challenges in isolation, sacrificing accuracy or relying on costly cryptographic tools. We propose ERIS, a serverless FL framework that balances privacy and accuracy while eliminating the server bottleneck and distributing the communication load. ERIS combines a model partitioning strategy, distributing aggregation across multiple client-side aggregators, with a distributed shifted gradient compression mechanism. We theoretically prove that ERIS (i) converges at the same rate as FedAvg under standard assumptions, and (ii) bounds mutual information leakage inversely with the number of aggregators, enabling strong privacy guarantees with no accuracy degradation. Experiments across image and text tasks, including large language models, confirm that ERIS achieves FedAvg-level accuracy while substantially reducing communication cost and improving robustness to membership inference and reconstruction attacks, without relying on heavy cryptography or noise injection.
[912] Sparse Models, Sparse Safety: Unsafe Routes in Mixture-of-Experts LLMs
Yukun Jiang, Hai Huang, Mingjie Li, Yage Zhang, Michael Backes, Yang Zhang
Main category: cs.LG
TL;DR: MoE LLMs have safety vulnerabilities through unsafe routing configurations that can be manipulated to produce harmful outputs, with proposed attack methods achieving high success rates and defensive measures suggested.
Details
Motivation: While MoE architectures reduce computational costs in LLMs, their safety risks remain underexplored. The sparse activation patterns in MoE models create potential vulnerabilities where specific routing configurations can convert safe outputs into harmful ones.Method: 1) Introduced Router Safety importance score (RoSais) to quantify safety criticality of routers; 2) Developed Fine-grained token-layer-wise Stochastic Optimization framework (F-SOUR) to discover unsafe routes considering sequentiality and dynamics of input tokens; 3) Tested across four MoE LLM families on JailbreakBench and AdvBench.
Result: Manipulating only 5 routers in DeepSeek-V2-Lite increased ASR by over 4× to 0.79. F-SOUR achieved average ASR of 0.90 on JailbreakBench and 0.98 on AdvBench across MoE LLMs. Demonstrated inherent safety risks in MoE architectures.
Conclusion: MoE LLMs have sparse safety vulnerabilities through unsafe routing configurations. The work reveals critical security risks in MoE architectures and proposes defensive measures including safety-aware route disabling and router training to safeguard these models.
Abstract: By introducing routers to selectively activate experts in Transformer layers, the mixture-of-experts (MoE) architecture significantly reduces computational costs in large language models (LLMs) while maintaining competitive performance, especially for models with massive parameters. However, prior work has largely focused on utility and efficiency, leaving the safety risks associated with this sparse architecture underexplored. In this work, we show that the safety of MoE LLMs is as sparse as their architecture by discovering unsafe routes: routing configurations that, once activated, convert safe outputs into harmful ones. Specifically, we first introduce the Router Safety importance score (RoSais) to quantify the safety criticality of each layer’s router. Manipulation of only the high-RoSais router(s) can flip the default route into an unsafe one. For instance, on JailbreakBench, masking 5 routers in DeepSeek-V2-Lite increases attack success rate (ASR) by over 4$\times$ to 0.79, highlighting an inherent risk that router manipulation may naturally occur in MoE LLMs. We further propose a Fine-grained token-layer-wise Stochastic Optimization framework to discover more concrete Unsafe Routes (F-SOUR), which explicitly considers the sequentiality and dynamics of input tokens. Across four representative MoE LLM families, F-SOUR achieves an average ASR of 0.90 and 0.98 on JailbreakBench and AdvBench, respectively. Finally, we outline defensive perspectives, including safety-aware route disabling and router training, as promising directions to safeguard MoE LLMs. We hope our work can inform future red-teaming and safeguarding of MoE LLMs. Our code is provided in https://github.com/TrustAIRLab/UnsafeMoE.
[913] CauScale: Neural Causal Discovery at Scale
Bo Peng, Sirui Chen, Jiaguo Tian, Yu Qiao, Chaochao Lu
Main category: cs.LG
TL;DR: CauScale is a neural architecture for efficient causal discovery that scales to 1000-node graphs using compression techniques and two-stream design.
Details
Motivation: Existing causal discovery approaches face significant time- and space-efficiency bottlenecks when scaling to large graphs, limiting their practical application in scientific AI and data analysis.Method: CauScale uses a reduction unit to compress data embeddings for time efficiency, tied attention weights for space efficiency, and a two-stream design with data stream for relational evidence extraction and graph stream for statistical priors integration.
Result: Achieves 99.6% mAP on in-distribution data and 84.4% on out-of-distribution data, with 4-13,000× inference speedups over prior methods, and scales to 500-node graphs during training where prior work fails.
Conclusion: CauScale successfully addresses scalability challenges in causal discovery, enabling efficient inference on large graphs up to 1000 nodes while maintaining high accuracy.
Abstract: Causal discovery is essential for advancing data-driven fields such as scientific AI and data analysis, yet existing approaches face significant time- and space-efficiency bottlenecks when scaling to large graphs. To address this challenge, we present CauScale, a neural architecture designed for efficient causal discovery that scales inference to graphs with up to 1000 nodes. CauScale improves time efficiency via a reduction unit that compresses data embeddings and improves space efficiency by adopting tied attention weights to avoid maintaining axis-specific attention maps. To keep high causal discovery accuracy, CauScale adopts a two-stream design: a data stream extracts relational evidence from high-dimensional observations, while a graph stream integrates statistical graph priors and preserves key structural signals. CauScale successfully scales to 500-node graphs during training, where prior work fails due to space limitations. Across testing data with varying graph scales and causal mechanisms, CauScale achieves 99.6% mAP on in-distribution data and 84.4% on out-of-distribution data, while delivering 4-13,000 times inference speedups over prior methods. Our project page is at https://github.com/OpenCausaLab/CauScale.
[914] LEFT: Learnable Fusion of Tri-view Tokens for Unsupervised Time Series Anomaly Detection
Dezheng Wang, Tong Chen, Guansong Pang, Congyan Chen, Shihua Li, Hongzhi Yin
Main category: cs.LG
TL;DR: LEFT is an unsupervised time series anomaly detection framework that models anomalies as inconsistencies across three complementary views: frequency-domain, time-domain, and multi-scale representations, with novel consistency constraints for cross-view agreement.
Details
Motivation: Many anomalies in time series are too subtle to detect in any single view (time, frequency, etc.) and only manifest as inconsistencies across multiple views. Existing cross-view methods lack analysis-synthesis consistency and don't enforce proper cross-view agreement.Method: LEFT learns feature tokens from three views: frequency-domain tokens (periodicity), time-domain tokens (local dynamics), and multi-scale tokens (varying granularities). Uses adaptive Nyquist-constrained spectral filters for multi-scale encoding. Introduces reconstruction of fine-grained targets from coarser structures and time-frequency cycle consistency constraints.
Result: Achieves best detection accuracy against state-of-the-art baselines on real-world benchmarks, with 5x reduction in FLOPs and 8x speed-up for training.
Conclusion: LEFT provides an effective unified framework for unsupervised time series anomaly detection by modeling anomalies as cross-view inconsistencies with explicit consistency constraints, achieving superior performance and efficiency.
Abstract: As a fundamental data mining task, unsupervised time series anomaly detection (TSAD) aims to build a model for identifying abnormal timestamps without assuming the availability of annotations. A key challenge in unsupervised TSAD is that many anomalies are too subtle to exhibit detectable deviation in any single view (e.g., time domain), and instead manifest as inconsistencies across multiple views like time, frequency, and a mixture of resolutions. However, most cross-view methods rely on feature or score fusion and do not enforce analysis-synthesis consistency, meaning the frequency branch is not required to reconstruct the time signal through an inverse transform, and vice versa. In this paper, we present Learnable Fusion of Tri-view Tokens (LEFT), a unified unsupervised TSAD framework that models anomalies as inconsistencies across complementary representations. LEFT learns feature tokens from three views of the same input time series: frequency-domain tokens that embed periodicity information, time-domain tokens that capture local dynamics, and multi-scale tokens that learns abnormal patterns at varying time series granularities. By learning a set of adaptive Nyquist-constrained spectral filters, the original time series is rescaled into multiple resolutions and then encoded, allowing these multi-scale tokens to complement the extracted frequency- and time-domain information. When generating the fused representation, we introduce a novel objective that reconstructs fine-grained targets from coarser multi-scale structure, and put forward an innovative time-frequency cycle consistency constraint to explicitly regularize cross-view agreement. Experiments on real-world benchmarks show that LEFT yields the best detection accuracy against SOTA baselines, while achieving a 5x reduction on FLOPs and 8x speed-up for training.
[915] Projected Gradient Ascent for Efficient Reward-Guided Updates with One-Step Generative Models
Jisung Hwang, Minhyuk Sung
Main category: cs.LG
TL;DR: Constrained latent optimization method for reward-guided generation that preserves white Gaussian noise characteristics with negligible overhead, preventing reward hacking while being efficient.
Details
Motivation: Test-time latent optimization can improve reward-guided generations from pretrained models but suffers from reward hacking (degrading quality) and is too slow for practical use. Need to make optimization both efficient and reliable.Method: Replace soft regularization with hard white Gaussian noise constraints via projected gradient ascent. Apply closed-form projection after each update to keep latent vector explicitly noise-like throughout optimization, preventing drift that leads to unrealistic artifacts.
Result: Method reaches comparable Aesthetic Score using only 30% of wall-clock time required by SOTA regularization-based method, while preventing reward hacking. Projection adds minimal cost with O(N log N) complexity.
Conclusion: Constrained latent optimization with hard noise constraints enables efficient and reliable reward-guided generation from pretrained models without reward hacking artifacts.
Abstract: We propose a constrained latent optimization method for reward-guided generation that preserves white Gaussian noise characteristics with negligible overhead. Test-time latent optimization can unlock substantially better reward-guided generations from pretrained generative models, but it is prone to reward hacking that degrades quality and also too slow for practical use. In this work, we make test-time optimization both efficient and reliable by replacing soft regularization with hard white Gaussian noise constraints enforced via projected gradient ascent. Our method applies a closed-form projection after each update to keep the latent vector explicitly noise-like throughout optimization, preventing the drift that leads to unrealistic artifacts. This enforcement adds minimal cost: the projection matches the $O(N \log N)$ complexity of standard algorithms such as sorting or FFT and does not practically increase wall-clock time. In experiments, our approach reaches a comparable Aesthetic Score using only 30% of the wall-clock time required by the SOTA regularization-based method, while preventing reward hacking.
[916] From Robotics to Sepsis Treatment: Offline RL via Geometric Pessimism
Sarthak Wanjari
Main category: cs.LG
TL;DR: Geo-IQL: A compute-efficient offline RL framework that adds density-based penalties using k-nearest-neighbor distances in state-action space to prevent overestimation of out-of-distribution actions.
Details
Motivation: Offline RL suffers from overestimation of out-of-distribution actions, especially with sparse data. Existing methods trade computational efficiency for performance - CQL is rigorous but computationally expensive, while IQL is efficient but fails on pathological datasets.Method: Geometric Pessimism framework augments IQL with density-based penalties derived from k-nearest-neighbor distances in state-action embedding space. Pre-computed penalties are applied via reward shaping with O(1) training overhead.
Result: Geo-IQL outperforms standard IQL on D4RL MuJoCo medium-replay tasks by over 18 points, reduces inter-seed variance by 4x, and doesn’t degrade performance on stable manifolds. On MIMIC-III Sepsis dataset, Geo-IQL achieves 86.4% terminal agreement with clinicians vs IQL’s 75%.
Conclusion: Geometric pessimism provides necessary regularization to safely overcome local optima in critical real-world decision systems, offering compute-efficient OOD conservatism without performance degradation on stable data manifolds.
Abstract: Offline Reinforcement Learning (RL) promises the recovery of optimal policies from static datasets, yet it remains susceptible to the overestimation of out-of-distribution (OOD) actions, particularly in fractured and sparse data manifolds.Current solutions necessitates a trade off between computational efficiency and performance. Methods like CQL offers rigorous conservatism but require tremendous compute power while efficient expectile-based methods like IQL often fail to correct OOD errors on pathological datasets, collapsing to Behavioural Cloning. In this work, we propose Geometric Pessimism, a modular, compute-efficient framework that augments standard IQL with density-based penalty derived from k-nearest-neighbour distances in the state-action embedding space. By pre-computing the penalties applied to each state-action pair our method injects OOD conservatism via reward shaping with a O(1) training overhead. Evaluated on the D4Rl MuJoCo benchmark, our method, Geo-IQL outperforms standard IQL on sensitive and unstable medium-replay tasks by over 18 points, while reducing inter-seed variance by 4x. Furthermore, Geo-IQL does not degrade performance on stable manifolds. Crucially, we validate our algorithm on the MIMIC-III Sepsis critical care dataset. While standard IQL collapses to behaviour cloning, Geo-IQL demonstrates active policy improvement. Maintaining safety constraints, achieving 86.4% terminal agreement with clinicians compared to IQL’s 75%. Our results suggest that geometric pessimism provides the necessary regularisation to safely overcome local optima in critical, real-world decision systems.
[917] Two-Stage Data Synthesization: A Statistics-Driven Restricted Trade-off between Privacy and Prediction
Xiaotong Liu, Shao-Bo Lin, Jun Fan, Ding-Xuan Zhou
Main category: cs.LG
TL;DR: Two-stage synthetic data generation strategy that balances privacy protection with prediction performance through synthesis-then-hybrid approach and KRR-based synthesis.
Details
Motivation: Existing synthetic data methods struggle to balance privacy requirements (needing significant data perturbations) with prediction performance (sensitive to such perturbations). Single-stage designs can't adequately address this trade-off.Method: Two-stage approach: 1) Synthesis-then-hybrid strategy generates pure synthetic data then fuses with original data; 2) KRR-based synthesis trains kernel ridge regression on original data to generate synthetic outputs from first-stage synthetic inputs.
Result: The method enables statistics-driven restricted privacy-prediction trade-off with optimal prediction performance guarantees, validated theoretically and numerically on marketing problem and five real-world datasets.
Conclusion: The proposed two-stage synthesis strategy effectively balances privacy protection and prediction performance through theoretical KRR strengths and covariant distribution retention, offering generalizable solution for synthetic data generation.
Abstract: Synthetic data have gained increasing attention across various domains, with a growing emphasis on their performance in downstream prediction tasks. However, most existing synthesis strategies focus on maintaining statistical information. Although some studies address prediction performance guarantees, their single-stage synthesis designs make it challenging to balance the privacy requirements that necessitate significant perturbations and the prediction performance that is sensitive to such perturbations. We propose a two-stage synthesis strategy. In the first stage, we introduce a synthesis-then-hybrid strategy, which involves a synthesis operation to generate pure synthetic data, followed by a hybrid operation that fuses the synthetic data with the original data. In the second stage, we present a kernel ridge regression (KRR)-based synthesis strategy, where a KRR model is first trained on the original data and then used to generate synthetic outputs based on the synthetic inputs produced in the first stage. By leveraging the theoretical strengths of KRR and the covariant distribution retention achieved in the first stage, our proposed two-stage synthesis strategy enables a statistics-driven restricted privacy–prediction trade-off and guarantee optimal prediction performance. We validate our approach and demonstrate its characteristics of being statistics-driven and restricted in achieving the privacy–prediction trade-off both theoretically and numerically. Additionally, we showcase its generalizability through applications to a marketing problem and five real-world datasets.
[918] Equalized Generative Treatment: Matching f-divergences for Fairness in Generative Models
Alexandre Verine, Rafael Pinot, Florian Le Bronnec
Main category: cs.LG
TL;DR: Proposes EGT, a new fairness definition for generative models that requires comparable generation quality across sensitive groups, not just balanced probabilities, and shows min-max fine-tuning achieves this fairness.
Details
Motivation: Existing fairness notions for generative models focus on balancing probabilities of generating samples from each sensitive group, but these are brittle as they can be met even when different groups are modeled with widely varying quality.Method: Introduces Equalized Generative Treatment (EGT) fairness definition requiring comparable generation quality across sensitive groups measured via reference f-divergence. Proposes min-max fine-tuning method to balance f-divergences across groups.
Result: Theoretical analysis shows fairness constraints couple overall model quality to most challenging group. Experiments on image and text generation tasks demonstrate min-max methods achieve fairer outcomes compared to other approaches while maintaining competitive overall performance.
Conclusion: EGT provides a more robust fairness definition for generative models, and min-max fine-tuning effectively achieves this fairness while maintaining good overall performance across different generation tasks.
Abstract: Fairness is a crucial concern for generative models, which not only reflect but can also amplify societal and cultural biases. Existing fairness notions for generative models are largely adapted from classification and focus on balancing the probability of generating samples from each sensitive group. We show that such criteria are brittle, as they can be met even when different sensitive groups are modeled with widely varying quality. To address this limitation, we introduce a new fairness definition for generative models, termed as equalized generative treatment (EGT), which requires comparable generation quality across all sensitive groups, with quality measured via a reference f-divergence. We further analyze the trade-offs induced by EGT, demonstrating that enforcing fairness constraints necessarily couples the overall model quality to that of the most challenging group to approximate. This indicates that a simple yet efficient min-max fine-tuning method should be able to balance f-divergences across sensitive groups to satisfy EGT. We validate this theoretical insight through a set of experiments on both image and text generation tasks. We demonstrate that min-max methods consistently achieve fairer outcomes compared to other approaches from the literature, while maintaining competitive overall performance for both tasks.
[919] LLaDA2.1: Speeding Up Text Diffusion via Token Editing
Tiwei Bie, Maosong Cao, Xiang Cao, Bingsen Chen, Fuyuan Chen, Kun Chen, Lun Du, Daozhuo Feng, Haibo Feng, Mingliang Gong, Zhuocheng Gong, Yanmei Gu, Jian Guan, Kaiyuan Guan, Hongliang He, Zenan Huang, Juyong Jiang, Zhonghui Jiang, Zhenzhong Lan, Chengxi Li, Jianguo Li, Zehuan Li, Huabin Liu, Lin Liu, Guoshan Lu, Yuan Lu, Yuxin Ma, Xingyu Mou, Zhenxuan Pan, Kaida Qiu, Yuji Ren, Jianfeng Tan, Yiding Tian, Zian Wang, Lanning Wei, Tao Wu, Yipeng Xing, Wentao Ye, Liangyu Zha, Tianze Zhang, Xiaolu Zhang, Junbo Zhao, Da Zheng, Hao Zhong, Wanli Zhong, Jun Zhou, Junlin Zhou, Liwang Zhu, Muzhi Zhu, Yihong Zhuang
Main category: cs.LG
TL;DR: LLaDA2.1 introduces a joint configurable threshold-decoding scheme combining Token-to-Token editing with Mask-to-Token diffusion, offering Speedy and Quality modes, plus RL alignment for better reasoning and instruction-following in 16B and 100B models.
Details
Motivation: To overcome the trade-off between decoding speed and generation quality in large diffusion language models, and to better align diffusion dynamics with complex human intent through reinforcement learning.Method: Joint configurable threshold-decoding scheme integrating Token-to-Token (T2T) editing into conventional Mask-to-Token (M2T) diffusion; two operational modes (Speedy and Quality); large-scale RL framework with stable gradient estimation for alignment.
Result: Strong performance across 33 benchmarks with lightning-fast decoding: 892 TPS on HumanEval+, 801 TPS on BigCodeBench, and 663 TPS on LiveCodeBench for the 100B model despite its size.
Conclusion: LLaDA2.1 successfully balances speed and quality in diffusion language models through innovative decoding schemes and RL alignment, achieving unprecedented throughput while maintaining strong task performance.
Abstract: While LLaDA2.0 showcased the scaling potential of 100B-level block-diffusion models and their inherent parallelization, the delicate equilibrium between decoding speed and generation quality has remained an elusive frontier. Today, we unveil LLaDA2.1, a paradigm shift designed to transcend this trade-off. By seamlessly weaving Token-to-Token (T2T) editing into the conventional Mask-to-Token (M2T) scheme, we introduce a joint, configurable threshold-decoding scheme. This structural innovation gives rise to two distinct personas: the Speedy Mode (S Mode), which audaciously lowers the M2T threshold to bypass traditional constraints while relying on T2T to refine the output; and the Quality Mode (Q Mode), which leans into conservative thresholds to secure superior benchmark performances with manageable efficiency degrade. Furthering this evolution, underpinned by an expansive context window, we implement the first large-scale Reinforcement Learning (RL) framework specifically tailored for dLLMs, anchored by specialized techniques for stable gradient estimation. This alignment not only sharpens reasoning precision but also elevates instruction-following fidelity, bridging the chasm between diffusion dynamics and complex human intent. We culminate this work by releasing LLaDA2.1-Mini (16B) and LLaDA2.1-Flash (100B). Across 33 rigorous benchmarks, LLaDA2.1 delivers strong task performance and lightning-fast decoding speed. Despite its 100B volume, on coding tasks it attains an astounding 892 TPS on HumanEval+, 801 TPS on BigCodeBench, and 663 TPS on LiveCodeBench.
[920] Dashed Line Defense: Plug-And-Play Defense Against Adaptive Score-Based Query Attacks
Yanzhang Fu, Zizheng Guo, Jizhou Luo
Main category: cs.LG
TL;DR: Dashed Line Defense (DLD) is a plug-and-play post-processing method that protects deep learning models against adaptive score-based query attacks by introducing ambiguity in loss feedback to disrupt adversarial example generation.
Details
Motivation: Existing runtime defenses against score-based query attacks are vulnerable to adaptive attacks, with even state-of-the-art methods being bypassable. There's a need for defenses that can withstand adaptive query strategies without requiring model parameter access.Method: DLD introduces ambiguity in how observed loss values reflect the true adversarial strength of candidate examples. It’s a plug-and-play post-processing method that disrupts attackers’ ability to reliably analyze and adapt their queries, preventing effective adversarial example generation.
Result: DLD consistently outperforms prior defenses on ImageNet, even under worst-case adaptive attacks, while preserving the model’s predicted labels. The method provides theoretical guarantees of defense capability.
Conclusion: DLD offers an effective defense against adaptive score-based query attacks by strategically introducing ambiguity in loss feedback, providing robust protection without compromising model predictions.
Abstract: Score-based query attacks pose a serious threat to deep learning models by crafting adversarial examples (AEs) using only black-box access to model output scores, iteratively optimizing inputs based on observed loss values. While recent runtime defenses attempt to disrupt this process via output perturbation, most either require access to model parameters or fail when attackers adapt their tactics. In this paper, we first reveal that even the state-of-the-art plug-and-play defense can be bypassed by adaptive attacks, exposing a critical limitation of existing runtime defenses. We then propose Dashed Line Defense (DLD), a plug-and-play post-processing method specifically designed to withstand adaptive query strategies. By introducing ambiguity in how the observed loss reflects the true adversarial strength of candidate examples, DLD prevents attackers from reliably analyzing and adapting their queries, effectively disrupting the AE generation process. We provide theoretical guarantees of DLD’s defense capability and validate its effectiveness through experiments on ImageNet, demonstrating that DLD consistently outperforms prior defenses–even under worst-case adaptive attacks–while preserving the model’s predicted labels.
[921] CompilerKV: Risk-Adaptive KV Compression via Offline Experience Compilation
Ning Yang, Chengzhi Wang, Yibo Liu, Baoliang Tian, Haijun Zhang
Main category: cs.LG
TL;DR: CompilerKV: A risk-adaptive and head-aware KV cache compression framework that uses offline-learned decision tables to optimize token retention under tight memory budgets, achieving near-full performance with significant gains over existing methods.
Details
Motivation: Current KV compression methods for LLMs in long-context scenarios suffer from linear KV cache memory growth and rely on static thresholds or coarse memory allocation, overlooking prompt-dependent compression risk variation and functional heterogeneity across attention heads, leading to unstable token selection and tail failures.Method: Proposes CompilerKV with two synergistic components: 1) Head Heterogeneity Table learned via offline contextual bandits to assign head-specific reliability weights, and 2) Risk-Adaptive Threshold Gating that jointly models attention entropy and local perplexity to transform prompt-level risk into deployable retention thresholds. The framework compiles offline experience into reusable decision tables for prefill-only deployment.
Result: On LongBench, CompilerKV dominates state-of-the-art methods under a 512-token budget, recovering 97.7% of FullKV performance while achieving up to +5.2 points gain over the strongest competitor.
Conclusion: CompilerKV effectively addresses the limitations of existing KV compression methods by considering both prompt-dependent risk variation and attention head heterogeneity, enabling efficient long-context processing with minimal performance degradation.
Abstract: Large Language Models (LLMs) in long-context scenarios are severely constrained by the linear growth of Key-Value (KV) cache memory. Existing KV compression methods rely either on static thresholds and attention-only heuristics or on coarse memory budget allocation. Under tight memory budgets, these methods overlook two key factors: prompt-dependent variation in compression risk and functional heterogeneity across attention heads, which destabilize token selection and lead to tail failures. To address these challenges, we propose CompilerKV, a risk-adaptive and head-aware compression framework that compiles offline experience into reusable decision tables for prefill-only deployment. CompilerKV integrates two key synergistic components: (i) a Head Heterogeneity Table, learned via offline contextual bandits, which assigns head-specific reliability weights to govern functional differences across attention heads explicitly; and (ii) a Risk-Adaptive Threshold Gating mechanism that jointly models attention entropy and local perplexity, transforming prompt-level risk into deployable retention thresholds. Experiments on LongBench show CompilerKV dominates SOTA methods under a 512-token budget, recovering 97.7% of FullKV performance while achieving up to +5.2 points gain over the strongest competitor.
[922] The Theory and Practice of MAP Inference over Non-Convex Constraints
Leander Kurscheidt, Gabriele Masina, Roberto Sebastiani, Antonio Vergari
Main category: cs.LG
TL;DR: A method for constrained maximum a posteriori (MAP) inference in probabilistic ML systems that handles non-convex constraints and complex densities through exact tractable fragments and domain partitioning with numerical optimization.
Details
Motivation: In safety-critical applications, probabilistic ML systems need to make predictions subject to algebraic constraints (e.g., obstacle avoidance), but real-world constraints are rarely convex and densities are not log-concave, making constrained MAP inference extremely challenging.Method: Two approaches: 1) Identify conditions for exact, efficient constrained MAP inference over continuous variables and develop a scalable message-passing algorithm for this tractable fragment. 2) A general constrained MAP strategy that partitions the domain into convex feasible regions combined with numerical constrained optimization.
Result: Both methods outperform constraint-agnostic baselines on synthetic and real-world benchmarks, and scale to complex densities that are intractable for state-of-the-art exact solvers.
Conclusion: The paper presents effective methods for constrained MAP inference that handle challenging non-convex constraints and complex densities, enabling reliable predictions in safety-critical applications.
Abstract: In many safety-critical settings, probabilistic ML systems have to make predictions subject to algebraic constraints, e.g., predicting the most likely trajectory that does not cross obstacles. These real-world constraints are rarely convex, nor the densities considered are (log-)concave. This makes computing this constrained maximum a posteriori (MAP) prediction efficiently and reliably extremely challenging. In this paper, we first investigate under which conditions we can perform constrained MAP inference over continuous variables exactly and efficiently and devise a scalable message-passing algorithm for this tractable fragment. Then, we devise a general constrained MAP strategy that interleaves partitioning the domain into convex feasible regions with numerical constrained optimization. We evaluate both methods on synthetic and real-world benchmarks, showing our % approaches outperform constraint-agnostic baselines, and scale to complex densities intractable for SoTA exact solvers.
[923] Learning To Sample From Diffusion Models Via Inverse Reinforcement Learning
Constant Bourdrez, Alexandre Vérine, Olivier Cappé
Main category: cs.LG
TL;DR: Learning sampling strategies for diffusion models via inverse reinforcement learning without retraining the denoiser
Details
Motivation: While training diffusion denoisers is computationally expensive, the sampling process is flexible and can be optimized. The paper aims to improve sample quality and sampling efficiency by learning optimal sampling strategies without retraining the underlying model.Method: Formulates diffusion sampling as a discrete-time finite-horizon Markov Decision Process where actions correspond to modifications of sampling dynamics. Uses inverse reinforcement learning with policy gradient techniques to optimize action scheduling without explicit reward functions, directly matching target behavior.
Result: Experimental evidence shows the approach can improve quality of samples generated by pretrained diffusion models and automatically tune sampling hyperparameters.
Conclusion: The proposed inverse reinforcement learning framework provides an effective way to optimize diffusion sampling strategies without expensive model retraining, improving both sample quality and efficiency.
Abstract: Diffusion models generate samples through an iterative denoising process, guided by a neural network. While training the denoiser on real-world data is computationally demanding, the sampling procedure itself is more flexible. This adaptability serves as a key lever in practice, enabling improvements in both the quality of generated samples and the efficiency of the sampling process. In this work, we introduce an inverse reinforcement learning framework for learning sampling strategies without retraining the denoiser. We formulate the diffusion sampling procedure as a discrete-time finite-horizon Markov Decision Process, where actions correspond to optional modifications of the sampling dynamics. To optimize action scheduling, we avoid defining an explicit reward function. Instead, we directly match the target behavior expected from the sampler using policy gradient techniques. We provide experimental evidence that this approach can improve the quality of samples generated by pretrained diffusion models and automatically tune sampling hyperparameters.
[924] SoK: The Pitfalls of Deep Reinforcement Learning for Cybersecurity
Shae McFadden, Myles Foley, Elizabeth Bates, Ilias Tsingenopoulos, Sanyam Vyas, Vasilios Mavroudis, Chris Hicks, Fabio Pierazzi
Main category: cs.LG
TL;DR: Systematic analysis of 11 methodological pitfalls in Deep Reinforcement Learning for cybersecurity applications, with prevalence quantification across 66 papers and experimental validation in three security domains.
Details
Motivation: DRL shows promise for cybersecurity but faces challenges transitioning from lab simulations to real cyber environments due to adversarial, non-stationary, and partially-observable nature of security tasks. Many papers contain methodological issues that undermine reliability.Method: Identified and systematized 11 pitfalls across environment modeling, agent training, performance evaluation, and system deployment stages. Analyzed 66 DRL4Sec papers (2018-2025) to quantify prevalence. Conducted controlled experiments in three domains: autonomous cyber defense, adversarial malware creation, and web security testing.
Result: Found average of over five pitfalls per paper across the literature. Experimental validation demonstrated practical impact of these pitfalls on system performance and reliability.
Conclusion: DRL for cybersecurity suffers from widespread methodological issues. Provided actionable recommendations for each pitfall to improve rigor and deployability of DRL-based security systems.
Abstract: Deep Reinforcement Learning (DRL) has achieved remarkable success in domains requiring sequential decision-making, motivating its application to cybersecurity problems. However, transitioning DRL from laboratory simulations to bespoke cyber environments can introduce numerous issues. This is further exacerbated by the often adversarial, non-stationary, and partially-observable nature of most cybersecurity tasks. In this paper, we identify and systematize 11 methodological pitfalls that frequently occur in DRL for cybersecurity (DRL4Sec) literature across the stages of environment modeling, agent training, performance evaluation, and system deployment. By analyzing 66 significant DRL4Sec papers (2018-2025), we quantify the prevalence of each pitfall and find an average of over five pitfalls per paper. We demonstrate the practical impact of these pitfalls using controlled experiments in (i) autonomous cyber defense, (ii) adversarial malware creation, and (iii) web security testing environments. Finally, we provide actionable recommendations for each pitfall to support the development of more rigorous and deployable DRL-based security systems.
[925] QUOKA: Query-Oriented KV Selection For Efficient LLM Prefill
Dalton Jones, Junyoung Park, Matthew Morse, Mingu Lee, Chris Lott, Harper Langston
Main category: cs.LG
TL;DR: QUOKA is a training-free sparse attention method that accelerates transformer inference by selecting representative queries and their most relevant keys, achieving near-baseline accuracy with significant speedups.
Details
Motivation: The paper addresses the computational inefficiency of full attention in transformer inference, particularly during chunked prefill, where many queries focus on a smaller subset of keys. The goal is to accelerate inference while maintaining accuracy.Method: QUOKA uses query-oriented key-value selection: (1) identifies queries with low cosine similarity to the mean query (which interact more strongly with keys), (2) retains these representative queries, and (3) subselects keys most aligned with those queries to approximate full attention behavior.
Result: Achieves 3x reduction in time-to-first-token, 5x speedup in attention on Nvidia GPUs, up to 7x speedup on Intel Xeon CPUs, while using 88% fewer key-value pairs and maintaining near-baseline accuracy on Needle-In-A-Haystack, LongBench, RULER, and Math500 benchmarks.
Conclusion: QUOKA provides an effective hardware-agnostic sparse attention algorithm that significantly accelerates transformer inference with minimal accuracy loss, demonstrating practical efficiency gains across different hardware platforms.
Abstract: We present QUOKA: Query-oriented KV selection for efficient attention, a training-free and hardware agnostic sparse attention algorithm for accelerating transformer inference under chunked prefill. While many queries focus on a smaller group of keys in the attention operator, we observe that queries with low cosine similarity with respect to the mean query interact more strongly with more keys and have the greatest contribution to final attention logits. By prioritizing these low cosine similarity queries, the behavior of full attention during the prefill stage can be closely approximated. QUOKA leverages this observation, accelerating attention by (1) first retaining a small set of representative queries and (2) then subselectin the keys most aligned with those queries. Through experiments on Needle-In-A-Haystack, LongBench, RULER, and Math500, we show that, while realizing a 3x reduction in time-to-first-token, 5x speedup in attention on Nvidia GPUs and up to nearly a 7x speedup on Intel Xeon CPUs, QUOKA achieves near-baseline accuracy, utilizing 88% fewer key-value pairs per attention evaluation.
[926] Reasoning aligns language models to human cognition
Gonçalo Guiomar, Elia Torre, Pehuen Moure, Victoria Shavina, Mario Giulianelli, Shih-Chii Liu, Valerio Mante
Main category: cs.LG
TL;DR: LLMs with chain-of-thought reasoning show human-like evidence accumulation and decision-making in probabilistic reasoning tasks, but still lag in active information acquisition compared to humans.
Details
Motivation: To understand whether language models make decisions under uncertainty like humans, and to investigate the role of chain-of-thought reasoning in their decision processes, particularly in separating evidence acquisition from evidence integration.Method: Introduce an active probabilistic reasoning task that separates sampling (evidence acquisition) from inference (evidence integration). Benchmark humans and various LLMs against near-optimal reference policies. Fit a mechanistic model with four interpretable latent variables: memory, strategy, choice bias, and occlusion awareness.
Result: Extended reasoning (chain-of-thought) is key for strong performance, driving large gains in inference and producing human-like belief trajectories, but yields only modest improvements in active sampling. The mechanistic model places humans and models in shared cognitive space and shows CoT shifts LLMs toward human-like evidence accumulation and belief-to-choice mapping.
Conclusion: Chain-of-thought reasoning makes LLMs more human-like in evidence integration and decision-making, tightening alignment in inference, but a persistent gap remains in information acquisition capabilities compared to humans.
Abstract: Do language models make decisions under uncertainty like humans do, and what role does chain-of-thought (CoT) reasoning play in the underlying decision process? We introduce an active probabilistic reasoning task that cleanly separates sampling (actively acquiring evidence) from inference (integrating evidence toward a decision). Benchmarking humans and a broad set of contemporary large language models against near-optimal reference policies reveals a consistent pattern: extended reasoning is the key determinant of strong performance, driving large gains in inference and producing belief trajectories that become strikingly human-like, while yielding only modest improvements in active sampling. To explain these differences, we fit a mechanistic model that captures systematic deviations from optimal behavior via four interpretable latent variables: memory, strategy, choice bias, and occlusion awareness. This model places humans and models in a shared low-dimensional cognitive space, reproduces behavioral signatures across agents, and shows how chain-of-thought shifts language models toward human-like regimes of evidence accumulation and belief-to-choice mapping, tightening alignment in inference while leaving a persistent gap in information acquisition.
[927] On the Expressive Power of GNNs for Boolean Satisfiability
Saku Peltonen, Roger Wattenhofer
Main category: cs.LG
TL;DR: GNNs for SAT solving have limited expressive power - higher-order WL tests cannot distinguish satisfiable from unsatisfiable instances, and industrial SAT instances often require more expressivity than random instances.
Details
Motivation: To understand the expressive power limitations of Graph Neural Networks for Boolean Satisfiability solving, particularly whether they can distinguish between satisfiable and unsatisfiable instances.Method: Analyze GNN expressivity through Weisfeiler-Leman (WL) test framework, prove theoretical limitations of WL hierarchy for SAT solving, study expressivity needs for different SAT instance families (regular, random, planar), and conduct experiments on G4SAT benchmark and industrial SAT competition instances.
Result: The full WL hierarchy cannot generally distinguish satisfiable from unsatisfiable SAT instances. Random instances are largely distinguishable by GNNs, but industrial instances often require more expressivity to predict satisfying assignments.
Conclusion: GNNs have fundamental expressive limitations for SAT solving, particularly for distinguishing satisfiability, and industrial SAT instances pose greater challenges than random instances, suggesting need for more expressive architectures.
Abstract: Machine learning approaches to solving Boolean Satisfiability (SAT) aim to replace handcrafted heuristics with learning-based models. Graph Neural Networks have emerged as the main architecture for SAT solving, due to the natural graph representation of Boolean formulas. We analyze the expressive power of GNNs for SAT solving through the lens of the Weisfeiler-Leman (WL) test. As our main result, we prove that the full WL hierarchy cannot, in general, distinguish between satisfiable and unsatisfiable instances. We show that indistinguishability under higher-order WL carries over to practical limitations for WL-bounded solvers that set variables sequentially. We further study the expressivity required for several important families of SAT instances, including regular, random and planar instances. To quantify expressivity needs in practice, we conduct experiments on random instances from the G4SAT benchmark and industrial instances from the International SAT Competition. Our results suggest that while random instances are largely distinguishable, industrial instances often require more expressivity to predict a satisfying assignment.
[928] Trapped by simplicity: When Transformers fail to learn from noisy features
Evan Peters, Ando Deng, Matheus H. Zambianco, Devin Blankespoor, Achim Kempf
Main category: cs.LG
TL;DR: Transformers show mixed performance on noise-robust learning of boolean functions - they succeed on some structured functions (k-sparse parity, majority) but fail on random k-juntas due to simplicity bias and sensitivity differences.
Details
Motivation: Understanding whether transformers trained on noisy data can generalize to noiseless inputs, and investigating their noise-robust learning capabilities compared to other architectures like LSTMs.Method: Study transformers’ performance on noise-robust learning tasks with boolean functions (k-sparse parity, majority, random k-juntas). Analyze failure cases, propose hypothesis about simplicity bias and sensitivity differences, and test with additional loss term penalizing high-sensitivity solutions.
Result: Transformers succeed on structured functions (k-sparse parity, majority) but fail on random k-juntas. LSTMs fail even on modest noise. Transformers’ failure is due to simplicity bias combined with optimal noise-robust functions having lower sensitivity than target functions.
Conclusion: Transformers are particularly ineffective for learning boolean functions in the presence of feature noise, showing limitations in noise-robust learning despite their general capabilities.
Abstract: Noise is ubiquitous in data used to train large language models, but it is not well understood whether these models are able to correctly generalize to inputs generated without noise. Here, we study noise-robust learning: are transformers trained on data with noisy features able to find a target function that correctly predicts labels for noiseless features? We show that transformers succeed at noise-robust learning for a selection of $k$-sparse parity and majority functions, compared to LSTMs which fail at this task for even modest feature noise. However, we find that transformers typically fail at noise-robust learning of random $k$-juntas, especially when the boolean sensitivity of the optimal solution is smaller than that of the target function. We argue that this failure is due to a combination of two factors: transformers’ bias toward simpler functions, combined with an observation that the optimal function for noise-robust learning typically has lower sensitivity than the target function for random boolean functions. We test this hypothesis by exploiting transformers’ simplicity bias to trap them in an incorrect solution, but show that transformers can escape this trap by training with an additional loss term penalizing high-sensitivity solutions. Overall, we find that transformers are particularly ineffective for learning boolean functions in the presence of feature noise.
[929] Data Reconstruction: Identifiability and Optimization with Sample Splitting
Yujie Shen, Zihan Wang, Jian Qian, Qi Lei
Main category: cs.LG
TL;DR: Training data reconstruction from KKT conditions: theoretical identifiability analysis for two-layer networks with polynomial activations, plus sample splitting optimization technique to improve reconstruction performance.
Details
Motivation: While training data reconstruction from KKT conditions has shown empirical success, there's a lack of theoretical understanding about when reconstruction is possible (identifiability) and how to reliably solve the optimization problems involved.Method: Two-pronged approach: 1) Theoretical analysis of identifiability conditions for KKT systems of two-layer networks with polynomial activations, 2) Introduction of sample splitting technique - a curvature-aware refinement step applicable to general reconstruction objectives that creates additional descent directions to escape poor stationary points.
Result: Provides sufficient conditions for KKT systems to uniquely determine training data, offering theoretical explanation of when reconstruction is possible. Experiments show that augmenting existing reconstruction methods with sample splitting consistently improves reconstruction performance.
Conclusion: The paper addresses both theoretical identifiability and practical optimization challenges in training data reconstruction, providing both theoretical foundations and practical improvements through sample splitting technique.
Abstract: Training data reconstruction from KKT conditions has shown striking empirical success, yet it remains unclear when the resulting KKT equations have unique solutions and, even in identifiable regimes, how to reliably recover solutions by optimization. This work hereby focuses on these two complementary questions: identifiability and optimization. On the identifiability side, we discuss the sufficient conditions for KKT system of two-layer networks with polynomial activations to uniquely determine the training data, providing a theoretical explanation of when and why reconstruction is possible. On the optimization side, we introduce sample splitting, a curvature-aware refinement step applicable to general reconstruction objectives (not limited to KKT-based formulations): it creates additional descent directions to escape poor stationary points and refine solutions. Experiments demonstrate that augmenting several existing reconstruction methods with sample splitting consistently improves reconstruction performance.
[930] FreqLens: Interpretable Frequency Attribution for Time Series Forecasting
Chi-Sheng Chen, Xinyu Zhang, En-Jui Kuo, Guan-Ying Chen, Qiuzhe Xie, Fan Zhang
Main category: cs.LG
TL;DR: FreqLens is an interpretable time series forecasting framework that discovers learnable frequency components and provides axiomatic frequency attribution with theoretical guarantees.
Details
Motivation: Time series forecasting models often lack interpretability, limiting adoption in domains requiring explainable predictions. There's a need for models that can provide transparent explanations for their forecasts.Method: Two key innovations: (1) Learnable frequency discovery - frequency bases parameterized via sigmoid mapping and learned from data with diversity regularization, enabling automatic discovery of dominant periodic patterns; (2) Axiomatic frequency attribution - a theoretically grounded framework satisfying Completeness, Faithfulness, Null-Frequency, and Symmetry axioms, with per-frequency attributions equivalent to Shapley values.
Result: On Traffic and Weather datasets, FreqLens achieves competitive or superior performance while discovering physically meaningful frequencies: discovers 24-hour daily cycle (24.6±0.1h, 2.5% error) and 12-hour half-daily cycle (11.8±0.1h, 1.6% error) on Traffic, and weekly cycles (10× longer than input window) on Weather.
Conclusion: FreqLens demonstrates genuine frequency-level knowledge discovery with formal theoretical guarantees on attribution quality, providing interpretable forecasting with mathematically sound explanations.
Abstract: Time series forecasting models often lack interpretability, limiting their adoption in domains requiring explainable predictions. We propose \textsc{FreqLens}, an interpretable forecasting framework that discovers and attributes predictions to learnable frequency components. \textsc{FreqLens} introduces two key innovations: (1) \emph{learnable frequency discovery} – frequency bases are parameterized via sigmoid mapping and learned from data with diversity regularization, enabling automatic discovery of dominant periodic patterns without domain knowledge; and (2) \emph{axiomatic frequency attribution} – a theoretically grounded framework that provably satisfies Completeness, Faithfulness, Null-Frequency, and Symmetry axioms, with per-frequency attributions equivalent to Shapley values. On Traffic and Weather datasets, \textsc{FreqLens} achieves competitive or superior performance while discovering physically meaningful frequencies: all 5 independent runs discover the 24-hour daily cycle ($24.6 \pm 0.1$h, 2.5% error) and 12-hour half-daily cycle ($11.8 \pm 0.1$h, 1.6% error) on Traffic, and weekly cycles ($10\times$ longer than the input window) on Weather. These results demonstrate genuine frequency-level knowledge discovery with formal theoretical guarantees on attribution quality.
[931] Foundation Inference Models for Ordinary Differential Equations
Maximilian Mauel, Johannes R. Hübers, David Berghaus, Patrick Seifner, Ramses J. Sanchez
Main category: cs.LG
TL;DR: FIM-ODE is a pretrained foundation model that infers ODE vector fields from noisy trajectory data in a single forward pass, achieving strong zero-shot performance and enabling fast finetuning without requiring ML expertise.
Details
Motivation: Current ODE inference methods (symbolic regression, Gaussian processes, Neural ODEs) require complex training pipelines, substantial ML expertise, or strong system-specific prior knowledge. There's a need for simpler, more accessible approaches to infer ODE vector fields from noisy trajectory data.Method: Pretrain FIM-ODE on a prior distribution over ODEs with low-degree polynomial vector fields, using neural operators to represent target fields. The model amortizes low-dimensional ODE inference by predicting vector fields directly from noisy trajectory data in a single forward pass.
Result: FIM-ODE achieves strong zero-shot performance, matching and often improving upon ODEFormer (a recent pretrained symbolic baseline) across various regimes despite using simpler pretraining priors. Pretraining provides strong initialization for finetuning, enabling fast and stable adaptation that outperforms modern neural and GP baselines.
Conclusion: FIM-ODE offers an effective, accessible approach to ODE inference that reduces the need for ML expertise while maintaining strong performance through pretraining and efficient finetuning.
Abstract: Ordinary differential equations (ODEs) are central to scientific modelling, but inferring their vector fields from noisy trajectories remains challenging. Current approaches such as symbolic regression, Gaussian process (GP) regression, and Neural ODEs often require complex training pipelines and substantial machine learning expertise, or they depend strongly on system-specific prior knowledge. We propose FIM-ODE, a pretrained Foundation Inference Model that amortises low-dimensional ODE inference by predicting the vector field directly from noisy trajectory data in a single forward pass. We pretrain FIM-ODE on a prior distribution over ODEs with low-degree polynomial vector fields and represent the target field with neural operators. FIM-ODE achieves strong zero-shot performance, matching and often improving upon ODEFormer, a recent pretrained symbolic baseline, across a range of regimes despite using a simpler pretraining prior distribution. Pretraining also provides a strong initialisation for finetuning, enabling fast and stable adaptation that outperforms modern neural and GP baselines without requiring machine learning expertise.
[932] Default Machine Learning Hyperparameters Do Not Provide Informative Initialization for Bayesian Optimization
Nicolás Villagrán Prieto, Eduardo C. Garrido-Merchán
Main category: cs.LG
TL;DR: Bayesian Optimization with default hyperparameter initialization shows no significant advantage over random initialization across multiple BO frameworks, models, and datasets.
Details
Motivation: To test whether default hyperparameter values from ML libraries contain useful expert knowledge that could accelerate Bayesian Optimization convergence, as opposed to starting with uniform random initialization.Method: Initialize BO with points drawn from truncated Gaussian distributions centered at library defaults, compare against uniform-random baseline across three BO back-ends (BoTorch, Optuna, Scikit-Optimize), three model families (Random Forests, SVMs, MLPs), and five benchmark datasets.
Result: Default-informed initialization yields no statistically significant advantage over random sampling (p-values 0.141-0.908). Tighter concentration around defaults improves early evaluations but this benefit vanishes as optimization progresses.
Conclusion: Library defaults don’t encode useful directional information for optimization; practitioners should treat hyperparameter tuning as integral to model development and use data-driven search strategies over heuristic reliance on defaults.
Abstract: Bayesian Optimization (BO) is a standard tool for hyperparameter tuning thanks to its sample efficiency on expensive black-box functions. While most BO pipelines begin with uniform random initialization, default hyperparameter values shipped with popular ML libraries such as scikit-learn encode implicit expert knowledge and could serve as informative starting points that accelerate convergence. This hypothesis, despite its intuitive appeal, has remained largely unexamined. We formalize the idea by initializing BO with points drawn from truncated Gaussian distributions centered at library defaults and compare the resulting trajectories against a uniform-random baseline. We conduct an extensive empirical evaluation spanning three BO back-ends (BoTorch, Optuna, Scikit-Optimize), three model families (Random Forests, Support Vector Machines, Multilayer Perceptrons), and five benchmark datasets covering classification and regression tasks. Performance is assessed through convergence speed and final predictive quality, and statistical significance is determined via one-sided binomial tests. Across all conditions, default-informed initialization yields no statistically significant advantage over purely random sampling, with p-values ranging from 0.141 to 0.908. A sensitivity analysis on the prior variance confirms that, while tighter concentration around the defaults improves early evaluations, this transient benefit vanishes as optimization progresses, leaving final performance unchanged. Our results provide no evidence that default hyperparameters encode useful directional information for optimization. We therefore recommend that practitioners treat hyperparameter tuning as an integral part of model development and favor principled, data-driven search strategies over heuristic reliance on library defaults.
[933] Central Dogma Transformer II: An AI Microscope for Understanding Cellular Regulatory Mechanisms
Nobuyuki Ota
Main category: cs.LG
TL;DR: CDT-II is an interpretable AI model for biology that mirrors the central dogma, using attention mechanisms to reveal regulatory networks directly from genomic data without supervision.
Details
Motivation: Current biological AI models lack interpretability - their internal representations don't correspond to biological relationships that researchers can examine. There's a need for AI models that reveal regulatory structure rather than just optimizing predictions.Method: CDT-II uses a transformer architecture that mirrors the central dogma: DNA self-attention for genomic relationships, RNA self-attention for gene co-regulation, and DNA-to-RNA cross-attention for transcriptional control. It takes only genomic embeddings and raw per-cell expression data.
Result: Applied to K562 CRISPRi data, CDT-II predicts perturbation effects with per-gene mean r=0.84 and recovers the GFI1B regulatory network without supervision (6.6-fold enrichment, P=3.5×10^-17). Two distinct attention mechanisms converged on an RNA processing module (P=1×10^-16).
Conclusion: CDT-II establishes mechanism-oriented AI as an alternative to task-oriented approaches, enabling experimental biologists to observe regulatory networks in their own data through directly interpretable attention maps.
Abstract: Current biological AI models lack interpretability – their internal representations do not correspond to biological relationships that researchers can examine. Here we present CDT-II, an “AI microscope” whose attention maps are directly interpretable as regulatory structure. By mirroring the central dogma in its architecture, each attention mechanism corresponds to a specific biological relationship: DNA self-attention for genomic relationships, RNA self-attention for gene co-regulation, and DNA-to-RNA cross-attention for transcriptional control. Using only genomic embeddings and raw per-cell expression, CDT-II enables experimental biologists to observe regulatory networks in their own data. Applied to K562 CRISPRi data, CDT-II predicts perturbation effects (per-gene mean $r = 0.84$) and recovers the GFI1B regulatory network without supervision (6.6-fold enrichment, $P = 3.5 \times 10^{-17}$). Two distinct attention mechanisms converge on an RNA processing module ($P = 1 \times 10^{-16}$). CDT-II establishes mechanism-oriented AI as an alternative to task-oriented approaches, revealing regulatory structure rather than merely optimizing predictions.
[934] $\texttt{lrnnx}$: A library for Linear RNNs
Karan Bania, Soham Kalburgi, Manit Tanwar, Dhruthi, Aditya Nagarsekar, Harshvardhan Mestha, Naman Chibber, Raj Deshmukh, Anish Sathyanarayanan, Aarush Rathore, Pratham Chheda
Main category: cs.LG
TL;DR: A unified software library called lrnnx that implements multiple linear recurrent neural network architectures under a common interface to address fragmentation in LRNN implementations.
Details
Motivation: Existing LRNN implementations are fragmented across different software frameworks, often rely on framework-specific optimizations, require custom CUDA kernels, or lack publicly available code, making it difficult to use, compare, or extend LRNNs.Method: Developed lrnnx library that implements several modern LRNN architectures under a common interface, exposing multiple levels of control from core components to higher-level model abstractions.
Result: Created a unified software library that improves accessibility, reproducibility, and extensibility of LRNN research and applications, available under a permissive MIT license.
Conclusion: lrnnx addresses the fragmentation in LRNN implementations and provides a standardized platform for research and applications in linear recurrent neural networks.
Abstract: Linear recurrent neural networks (LRNNs) provide a structured approach to sequence modeling that bridges classical linear dynamical systems and modern deep learning, offering both expressive power and theoretical guarantees on stability and trainability. In recent years, multiple LRNN-based architectures have been proposed, each introducing distinct parameterizations, discretization schemes, and implementation constraints. However, existing implementations are fragmented across different software frameworks, often rely on framework-specific optimizations, and in some cases require custom CUDA kernels or lack publicly available code altogether. As a result, using, comparing, or extending LRNNs requires substantial implementation effort. To address this, we introduce $\texttt{lrnnx}$, a unified software library that implements several modern LRNN architectures under a common interface. The library exposes multiple levels of control, allowing users to work directly with core components or higher-level model abstractions. $\texttt{lrnnx}$ aims to improve accessibility, reproducibility, and extensibility of LRNN research and applications. We make our code available under a permissive MIT license.
[935] Redundancy-Free View Alignment for Multimodal Human Activity Recognition with Arbitrarily Missing Views
Duc-Anh Nguyen, Nhien-An Le-Khac
Main category: cs.LG
TL;DR: RALIS: A multimodal multiview learning model for human activity recognition that handles arbitrary view combinations and missing views using contrastive learning with adjusted center loss and mixture-of-experts fusion.
Details
Motivation: Existing multimodal multiview learning approaches struggle with flexible view configurations including arbitrary view combinations, varying numbers of views, and heterogeneous modalities, especially in human activity recognition where sensor availability varies.Method: Combines multiview contrastive learning with adjusted center contrastive loss for self-supervised representation learning and view alignment, plus mixture-of-experts module with load balancing strategy to adapt to arbitrary view combinations. Reduces computational complexity from O(V²) to O(V).
Result: Validated on four datasets with inertial and human pose modalities (3-9 views), demonstrating performance and flexibility in handling arbitrary view availability during training and inference.
Conclusion: RALIS effectively addresses flexible view configurations in multimodal multiview learning for human activity recognition, handling missing views and arbitrary combinations through contrastive learning and mixture-of-experts fusion.
Abstract: Multimodal multiview learning seeks to integrate information from diverse sources to enhance task performance. Existing approaches often struggle with flexible view configurations, including arbitrary view combinations, numbers of views, and heterogeneous modalities. Focusing on the context of human activity recognition, we propose RALIS, a model that combines multiview contrastive learning with a mixture-of-experts module to support arbitrary view availability during both training and inference. Instead of trying to reconstruct missing views, an adjusted center contrastive loss is used for self-supervised representation learning and view alignment, mitigating the impact of missing views on multiview fusion. This loss formulation allows for the integration of view weights to account for view quality. Additionally, it reduces computational complexity from $O(V^2)$ to $O(V)$, where $V$ is the number of views. To address residual discrepancies not captured by contrastive learning, we employ a mixture-of-experts module with a specialized load balancing strategy, tasked with adapting to arbitrary view combinations. We highlight the geometric relationship among components in our model and how they combine well in the latent space. RALIS is validated on four datasets encompassing inertial and human pose modalities, with the number of views ranging from three to nine, demonstrating its performance and flexibility.
[936] Permissive-Washing in the Open AI Supply Chain: A Large-Scale Audit of License Integrity
James Jewitt, Gopi Krishnan Rajbahadur, Hao Li, Bram Adams, Ahmed E. Hassan
Main category: cs.LG
TL;DR: Empirical audit reveals widespread “permissive washing” in AI supply chains where 96.5% of datasets and 95.8% of models lack required license documentation despite permissive licensing claims.
Details
Motivation: To investigate the phenomenon of "permissive washing" - labeling AI artifacts as free to use while omitting required legal documentation, and to assess how widespread this issue is in the AI supply chain.Method: Empirical audit of 124,278 dataset→model→application supply chains across 3,338 datasets, 6,664 models, and 28,516 applications from Hugging Face and GitHub, checking compliance with license text, copyright notice, and attribution requirements.
Result: 96.5% of datasets and 95.8% of models lack required license text; only 2.3% of datasets and 3.2% of models satisfy both license text and copyright requirements; attribution rarely propagates downstream (27.59% of models preserve compliant dataset notices, 5.75% of applications preserve compliant model notices).
Conclusion: Practitioners cannot assume permissive labels confer the rights they claim - license files and notices, not metadata, are the source of legal truth. Widespread permissive washing exposes downstream users to litigation risk.
Abstract: Permissive licenses like MIT, Apache-2.0, and BSD-3-Clause dominate open-source AI, signaling that artifacts like models, datasets, and code can be freely used, modified, and redistributed. However, these licenses carry mandatory requirements: include the full license text, provide a copyright notice, and preserve upstream attribution, that remain unverified at scale. Failure to meet these conditions can place reuse outside the scope of the license, effectively leaving AI artifacts under default copyright for those uses and exposing downstream users to litigation. We call this phenomenon ``permissive washing’’: labeling AI artifacts as free to use, while omitting the legal documentation required to make that label actionable. To assess how widespread permissive washing is in the AI supply chain, we empirically audit 124,278 dataset $\rightarrow$ model $\rightarrow$ application supply chains, spanning 3,338 datasets, 6,664 models, and 28,516 applications across Hugging Face and GitHub. We find that an astonishing 96.5% of datasets and 95.8% of models lack the required license text, only 2.3% of datasets and 3.2% of models satisfy both license text and copyright requirements, and even when upstream artifacts provide complete licensing evidence, attribution rarely propagates downstream: only 27.59% of models preserve compliant dataset notices and only 5.75% of applications preserve compliant model notices (with just 6.38% preserving any linked upstream notice). Practitioners cannot assume permissive labels confer the rights they claim: license files and notices, not metadata, are the source of legal truth. To support future research, we release our full audit dataset and reproducible pipeline.
[937] HoGS: Homophily-Oriented Graph Synthesis for Local Differentially Private GNN Training
Wen Xu, Zhetao Li, Yong Xiao, Pengpeng Qiao, Mianxiong Dong, Kaoru Ota
Main category: cs.LG
TL;DR: HoGS is an LDP framework for training GNNs with both link and feature privacy protection by generating synthetic graphs using homophily properties.
Details
Motivation: Existing local differentially private GNNs either only protect link privacy or suffer significant utility loss when protecting both links and node features, creating a need for a more effective privacy-preserving GNN training method.Method: HoGS collects link and feature information under LDP, then leverages graph homophily to separately reconstruct graph structure and node features, generating a synthetic graph for downstream GNN training while preserving privacy.
Result: Experimental results on three real-world datasets show HoGS significantly outperforms baseline methods in GNN training accuracy while providing both link and feature privacy protection.
Conclusion: HoGS effectively addresses the privacy-utility trade-off in GNN training by using homophily-based synthetic graph generation under LDP constraints.
Abstract: Graph neural networks (GNNs) have demonstrated remarkable performance in various graph-based machine learning tasks by effectively modeling high-order interactions between nodes. However, training GNNs without protection may leak sensitive personal information in graph data, including links and node features. Local differential privacy (LDP) is an advanced technique for protecting data privacy in decentralized networks. Unfortunately, existing local differentially private GNNs either only preserve link privacy or suffer significant utility loss in the process of preserving link and node feature privacy. In this paper, we propose an effective LDP framework, called HoGS, which trains GNNs with link and feature protection by generating a synthetic graph. Concretely, HoGS first collects the link and feature information of the graph under LDP, and then utilizes the phenomenon of homophily in graph data to reconstruct the graph structure and node features separately, thereby effectively mitigating the negative impact of LDP on the downstream GNN training. We theoretically analyze the privacy guarantee of HoGS and conduct experiments using the generated synthetic graph as input to various state-of-the-art GNN architectures. Experimental results on three real-world datasets show that HoGS significantly outperforms baseline methods in the accuracy of training GNNs.
[938] Dr. MAS: Stable Reinforcement Learning for Multi-Agent LLM Systems
Lang Feng, Longtao Zheng, Shuo He, Fuxiang Zhang, Bo An
Main category: cs.LG
TL;DR: Dr. MAS: A stable RL training framework for multi-agent LLM systems that addresses gradient instability through agent-wise advantage normalization and provides end-to-end orchestration.
Details
Motivation: Multi-agent LLM systems enable advanced reasoning through role specialization, but existing reinforcement learning (RL) post-training methods suffer from instability when extended to multi-agent settings, particularly due to global normalization baselines that don't account for diverse agent reward distributions.Method: Proposes Dr. MAS with agent-wise advantage normalization: each agent’s advantages are normalized using its own reward statistics rather than a global baseline. This calibrates gradient scales and stabilizes training. The framework also includes scalable orchestration, flexible per-agent LLM serving, optimization configurations, and shared resource scheduling.
Result: Dr. MAS achieves significant improvements over vanilla GRPO: +5.6% avg@16 and +4.6% pass@16 on math reasoning, and +15.2% avg@16 and +13.1% pass@16 on multi-turn search benchmarks using Qwen2.5 and Qwen3 models. It eliminates gradient spikes and remains effective under heterogeneous agent-model assignments while improving efficiency.
Conclusion: Dr. MAS provides a stable and effective RL training framework for multi-agent LLM systems by addressing fundamental gradient instability issues through agent-wise normalization, enabling reliable post-training for complex multi-agent reasoning systems.
Abstract: Multi-agent LLM systems enable advanced reasoning and tool use via role specialization, yet reliable reinforcement learning (RL) post-training for such systems remains difficult. In this work, we theoretically pinpoint a key reason for training instability when extending group-based RL to multi-agent LLM systems. We show that under GRPO-style optimization, a global normalization baseline may deviate from diverse agents’ reward distributions, which ultimately leads to gradient-norm instability. Based on this finding, we propose Dr. MAS, a simple and stable RL training recipe for multi-agent LLM systems. Dr. MAS uses an agent-wise remedy: normalizing advantages per agent using each agent’s own reward statistics, which calibrates gradient scales and dramatically stabilizes training, both theoretically and empirically. Beyond the algorithm, Dr. MAS provides an end-to-end RL training framework for multi-agent LLM systems, supporting scalable orchestration, flexible per-agent LLM serving and optimization configs, and shared resource scheduling of LLM actor backends. We evaluate Dr. MAS on multi-agent math reasoning and multi-turn search benchmarks using Qwen2.5 and Qwen3 series models. Dr. MAS achieves clear gains over vanilla GRPO (e.g., +5.6% avg@16 and +4.6% pass@16 on math, and +15.2% avg@16 and +13.1% pass@16 on search) while largely eliminating gradient spikes. Moreover, it remains highly effective under heterogeneous agent-model assignments while improving efficiency.
[939] A Graphop Analysis of Graph Neural Networks on Sparse Graphs: Generalization and Universal Approximation
Ofek Amran, Tom Gilat, Ron Levie
Main category: cs.LG
TL;DR: The paper presents a unified metric space for graphs of all sizes (sparse and dense) where message passing neural networks are Hölder continuous, extending graphop analysis for improved approximation and generalization bounds.
Details
Motivation: Current analyses of MPNNs have limitations: they either only work for dense graphs of unbounded sizes or only for sparse graphs of uniformly bounded sizes. There's a need for a unified framework that handles both sparse and dense graphs of all sizes.Method: The authors define a compact metric on the space of graphs of all sizes using graphop analysis, which extends graph limit theory. This metric allows MPNNs to be shown as Hölder continuous functions on this unified graph space.
Result: The approach yields more powerful universal approximation theorems and generalization bounds than previous works, providing a comprehensive theoretical framework for analyzing MPNNs across all graph types and sizes.
Conclusion: The paper presents a unified theoretical framework for analyzing MPNNs that works for both sparse and dense graphs of all sizes, overcoming limitations of previous approaches and providing stronger theoretical guarantees.
Abstract: Generalization and approximation capabilities of message passing graph neural networks (MPNNs) are often studied by defining a compact metric on a space of input graphs under which MPNNs are Hölder continuous. Such analyses are of two varieties: 1) when the metric space includes graphs of unbounded sizes, the theory is only appropriate for dense graphs, and, 2) when studying sparse graphs, the metric space only includes graphs of uniformly bounded size. In this work, we present a unified approach, defining a compact metric on the space of graphs of all sizes, both sparse and dense, under which MPNNs are Hölder continuous. This leads to more powerful universal approximation theorems and generalization bounds than previous works. The theory is based on, and extends, a recent approach to graph limit theory called graphop analysis.
[940] AnomSeer: Reinforcing Multimodal LLMs to Reason for Time-Series Anomaly Detection
Junru Zhang, Lang Feng, Haoran Shi, Xu Guo, Han Yu, Yabo Dong, Duanqing Xu
Main category: cs.LG
TL;DR: AnomSeer enhances multimodal LLMs for time-series anomaly detection by grounding reasoning in structural details through expert chain-of-thought traces and novel time-series grounded policy optimization.
Details
Motivation: Current MLLMs for time-series anomaly detection rely on coarse heuristics and struggle with multi-dimensional, detailed reasoning needed for complex time-series data, creating a gap in precise anomaly understanding.Method: 1) Generate expert chain-of-thought traces from classical analyses (statistical measures, frequency transforms) for verifiable fine-grained reasoning. 2) Propose time-series grounded policy optimization (TimerPO) with time-series grounded advantage based on optimal transport and orthogonal projection to maintain primary detection objectives.
Result: AnomSeer with Qwen2.5-VL-3B/7B-Instruct outperforms larger commercial baselines (GPT-4o) in classification and localization accuracy, especially on point- and frequency-driven exceptions, while producing plausible reasoning traces.
Conclusion: Grounding MLLM reasoning in precise structural details of time series through expert traces and TimerPO significantly improves anomaly detection performance and provides verifiable explanations.
Abstract: Time-series anomaly detection (TSAD) with multimodal large language models (MLLMs) is an emerging area, yet a persistent challenge remains: MLLMs rely on coarse time-series heuristics but struggle with multi-dimensional, detailed reasoning, which is vital for understanding complex time-series data. We present AnomSeer to address this by reinforcing the model to ground its reasoning in precise, structural details of time series, unifying anomaly classification, localization, and explanation. At its core, an expert chain-of-thought trace is generated to provide a verifiable, fine-grained reasoning from classical analyses (e.g., statistical measures, frequency transforms). Building on this, we propose a novel time-series grounded policy optimization (TimerPO) that incorporates two additional components beyond standard reinforcement learning: a time-series grounded advantage based on optimal transport and an orthogonal projection to ensure this auxiliary granular signal does not interfere with the primary detection objective. Across diverse anomaly scenarios, AnomSeer, with Qwen2.5-VL-3B/7B-Instruct, outperforms larger commercial baselines (e.g., GPT-4o) in classification and localization accuracy, particularly on point- and frequency-driven exceptions. Moreover, it produces plausible time-series reasoning traces that support its conclusions.
[941] How2Everything: Mining the Web for How-To Procedures to Evaluate and Improve LLMs
Yapei Chang, Kyle Lo, Mohit Iyyer, Luca Soldaini
Main category: cs.LG
TL;DR: How2Everything is a scalable framework for evaluating and improving goal-conditioned procedure generation in LLMs, featuring mined procedures, a benchmark, and an evaluation protocol.
Details
Motivation: Measuring and improving procedural validity at scale on real-world tasks remains challenging and understudied, despite being a key LLM capability for how-to advice and step-by-step planning.Method: Developed How2Mine to extract 351K procedures from web pages, built How2Bench evaluation set, created How2Score evaluation protocol using LLM judges, and used RL with How2Score as reward to improve models.
Result: How2Bench reveals scaling trends, RL improves performance by >10 points on How2Bench without regressions on standard benchmarks, and the framework supports closed-loop capability evaluation and improvement.
Conclusion: How2Everything demonstrates how pretraining web data can support scalable evaluation and improvement of procedural generation capabilities in LLMs.
Abstract: Generating step-by-step “how-to” procedures is a key LLM capability: how-to advice is commonly requested in chatbots, and step-by-step planning is critical for reasoning over complex tasks. Yet, measuring and improving procedural validity at scale on real-world tasks remains challenging and understudied. To address this, we introduce How2Everything, a scalable framework to evaluate and improve goal-conditioned procedure generation. Our framework includes How2Mine, which mines 351K procedures from 980K web pages across 14 topics and readily scales to larger corpora. From this pool we build How2Bench, a 7K-example evaluation set balanced across topics. To reliably score model outputs, we develop How2Score, an evaluation protocol that uses an LLM judge to detect whether a generation contains any critical failure that would prevent achieving the goal. For low-cost, reproducible evaluation, we distill a frontier model into an open 8B model, achieving 80.5% agreement with human annotators. How2Bench reveals clear scaling trends across model sizes and training stages, providing signal early in pretraining. Finally, RL using How2Score as a reward improves performance on How2Bench by >10 points across three models without systematic regressions on standard benchmarks, with gains robust to superficial source-document memorization or format compliance. Taken together, How2Everything shows how pretraining web data can support a closed loop of capability evaluation and improvement at scale.
[942] The Geometry of Refusal in Large Language Models: Concept Cones and Representational Independence
Tom Wollschläger, Jannes Elstner, Simon Geisler, Vincent Cohen-Addad, Stephan Günnemann, Johannes Gasteiger
Main category: cs.LG
TL;DR: The paper proposes a gradient-based approach to representation engineering that identifies multiple independent refusal directions and multi-dimensional concept cones in LLMs, revealing complex spatial structures governing safety refusal mechanisms.
Details
Motivation: Current understanding of how adversarial inputs bypass LLM safety alignment is limited, with prior work suggesting a single refusal direction. The authors aim to better understand the mechanisms behind safety circumvention by exploring the representation space more comprehensively.Method: Developed a novel gradient-based approach to representation engineering to identify refusal directions in LLM activation space. Introduced the concept of “representational independence” that accounts for both linear and non-linear effects, going beyond simple orthogonality.
Result: Discovered multiple independent refusal directions and multi-dimensional concept cones that mediate refusal behavior. Showed that orthogonality alone doesn’t guarantee independence under intervention, and identified mechanistically independent refusal directions with complex spatial structures.
Conclusion: LLM refusal mechanisms are governed by complex spatial structures with multiple distinct, functionally independent directions driving refusal behavior. The gradient-based approach provides a foundation for future work on understanding LLM representations.
Abstract: The safety alignment of large language models (LLMs) can be circumvented through adversarially crafted inputs, yet the mechanisms by which these attacks bypass safety barriers remain poorly understood. Prior work suggests that a single refusal direction in the model’s activation space determines whether an LLM refuses a request. In this study, we propose a novel gradient-based approach to representation engineering and use it to identify refusal directions. Contrary to prior work, we uncover multiple independent directions and even multi-dimensional concept cones that mediate refusal. Moreover, we show that orthogonality alone does not imply independence under intervention, motivating the notion of representational independence that accounts for both linear and non-linear effects. Using this framework, we identify mechanistically independent refusal directions. We show that refusal mechanisms in LLMs are governed by complex spatial structures and identify functionally independent directions, confirming that multiple distinct mechanisms drive refusal behavior. Our gradient-based approach uncovers these mechanisms and can further serve as a foundation for future work on understanding LLMs.
[943] Efficient Deep Learning for Biometrics: Overview, Challenges and Trends in Ear of Frugal AI
Karim Haroun, Aya Zitouni, Aicha Zenakhri, Meriem Amel Guessoum, Larbi Boubchir
Main category: cs.LG
TL;DR: Survey paper on efficient deep learning methods for biometric applications, focusing on reducing computational demands and energy consumption while maintaining performance.
Details
Motivation: Deep learning advances benefit security/defense applications but have high computational demands leading to energy consumption, carbon footprint, and limitations on resource-constrained edge devices for real-time use.Method: Survey approach: taxonomy of efficient deep learning families, discussion of training/deployment challenges, complementary efficiency metrics (memory, computation, latency, throughput), and advocacy for universal reproducible metrics.
Result: Provides comprehensive overview of efficient deep learning techniques for biometrics, identifies key challenges, and establishes evaluation framework for model efficiency beyond just accuracy.
Conclusion: Efficient deep learning is crucial for sustainable and scalable biometric systems, with need for standardized metrics and future research directions in this area.
Abstract: Recent advances in deep learning, whether on discriminative or generative tasks have been beneficial for various applications, among which security and defense. However, their increasing computational demands during training and deployment translates directly into high energy consumption. As a consequence, this induces a heavy carbon footprint which hinders their widespread use and scalability, but also a limitation when deployed on resource-constrained edge devices for real-time use. In this paper, we briefly survey efficient deep learning methods for biometric applications. Specifically, we tackle the challenges one might incur when training and deploying deep learning approaches, and provide a taxonomy of the various efficient deep learning families. Additionally, we discuss complementary metrics for evaluating the efficiency of these models such as memory, computation, latency, throughput, and advocate for universal and reproducible metrics for better comparison. Last, we give future research directions to consider.
[944] Capacity-Aware Inference: Mitigating the Straggler Effect in Mixture of Experts
Shwai He, Weilin Cai, Jiayi Huang, Ang Li
Main category: cs.LG
TL;DR: Capacity-aware token dropping methods for MoE models to address load imbalance and straggler effect, improving inference speed with minimal performance impact
Details
Motivation: MoE models suffer from inference inefficiencies due to imbalanced token-to-expert assignment under expert parallelism, where overloaded experts create global delays (Straggler Effect)Method: Two approaches: 1) Capacity-Aware Token Drop enforces expert capacity limits by discarding excess tokens from overloaded experts; 2) Capacity-Aware Expanded Drop allows tokens to include additional local experts before enforcing capacity constraints
Result: 30% speedup with only 0.9% degradation on OLMoE; applying Expanded Drop to Mixtral-8×7B-Instruct yields 0.2% performance improvement and 1.85× inference speedup
Conclusion: Proposed capacity-aware methods effectively address load imbalance in MoE models, improving expert utilization, model performance, and inference efficiency across language and multimodal MoE models
Abstract: The Mixture of Experts (MoE) is an effective architecture for scaling large language models by leveraging sparse expert activation to balance performance and efficiency. However, under expert parallelism, MoE suffers from inference inefficiencies due to imbalanced token-to-expert assignment, where underloaded experts complete computations early but must wait for overloaded experts, leading to global delays. We define this phenomenon as the \textbf{\textit{Straggler Effect}}, as the most burdened experts dictate the overall inference latency. To address this, we first propose \textit{\textbf{Capacity-Aware Token Drop}}, which enforces expert capacity limits by discarding excess tokens from overloaded experts, effectively reducing load imbalance with minimal performance impact (e.g., $30%$ speedup with only $0.9%$ degradation on OLMoE). Next, given the presence of low-load experts remaining well below the capacity threshold, we introduce \textit{\textbf{Capacity-Aware Expanded Drop}}, which allows tokens to include additional local experts in their candidate set before enforcing strict local capacity constraints, thereby improving load balance and enhancing the utilization of underused experts. Extensive experiments on both language and multimodal MoE models demonstrate the effectiveness of our approach, yielding substantial gains in expert utilization, model performance, and inference efficiency, e.g., applying Expanded Drop to Mixtral-8$\times$7B-Instruct yields a {0.2%} average performance improvement and a {1.85$\times$} inference speedup. The code is released at: https://github.com/CASE-Lab-UMD/Capacity-Aware-MoE.
[945] Learning Potentials for Dynamic Matching and Application to Heart Transplantation
Itai Zilberstein, Ioannis Anagnostides, Zachary W. Sollie, Arman Kilic, Tuomas Sandholm
Main category: cs.LG
TL;DR: A novel framework for non-myopic policy optimization in online matching using potentials for heart transplant allocation, outperforming current approaches with real historical data.
Details
Motivation: Thousands of patients face life-threatening wait times for heart transplants due to organ scarcity. Current allocation policies fail to account for dynamic organ arrivals and waitlist composition, hampering efficiency. The US is transitioning from rigid rule-based allocation to flexible data-driven models.Method: Proposes a novel framework for non-myopic policy optimization in general online matching using potentials (originally from kidney exchange). Develops scalable ways of learning higher-dimensional, more expressive potentials through self-supervised imitation learning where potentials mimic an omniscient algorithm with perfect foresight.
Result: Using real historical data, the policies significantly outperform prior approaches including the current US status quo policy and proposed continuous distribution framework in optimizing population-level outcomes.
Conclusion: The analysis and methods come at a pivotal moment as the US heart transplant allocation system is under review, offering a scalable and theoretically grounded path toward more effective organ allocation.
Abstract: Each year, thousands of patients in need of heart transplants face life-threatening wait times due to organ scarcity. While allocation policies aim to maximize population-level outcomes, current approaches often fail to account for the dynamic arrival of organs and the composition of waitlisted candidates, thereby hampering efficiency. The United States is transitioning from rigid, rule-based allocation to more flexible data-driven models. In this paper, we propose a novel framework for non-myopic policy optimization in general online matching relying on potentials, a concept originally introduced for kidney exchange. We develop scalable and accurate ways of learning potentials that are higher-dimensional and more expressive than prior approaches. Our approach is a form of self-supervised imitation learning: the potentials are trained to mimic an omniscient algorithm that has perfect foresight. We focus on the application of heart transplant allocation and demonstrate, using real historical data, that our policies significantly outperform prior approaches – including the current US status quo policy and the proposed continuous distribution framework – in optimizing for population-level outcomes. Our analysis and methods come at a pivotal moment in US policy, as the current heart transplant allocation system is under review. We propose a scalable and theoretically grounded path toward more effective organ allocation.
[946] Robust Policy Optimization to Prevent Catastrophic Forgetting
Mahdi Sabbaghi, George Pappas, Adel Javanmard, Hamed Hassani
Main category: cs.LG
TL;DR: FRPO is a robust RLHF framework that optimizes policies to maintain reward stability across KL-bounded neighborhoods reachable by downstream fine-tuning, preventing catastrophic forgetting of safety behaviors.
Details
Motivation: Standard RLHF objectives don't guarantee robustness to downstream fine-tuning, leading to catastrophic forgetting of important behaviors like safety. Current approaches focus on downstream-time preservation methods, but the authors argue for building robustness during pre-finetuning to avoid brittle high-reward solutions.Method: Proposes Fine-tuning Robust Policy Optimization (FRPO), a robust RLHF framework using a max-min formulation that optimizes reward not only at current policy but across KL-bounded neighborhoods of policies reachable by downstream adaptation. Modifies GRPO algorithm with no extra computation.
Result: FRPO substantially reduces safety degradation across multiple base models and downstream fine-tuning regimes (SFT and RL) while preserving downstream task performance. Also preserves math accuracy under subsequent fine-tuning in math-focused RL setting.
Conclusion: FRPO provides an effective approach to building robust policies during RLHF that maintain important behaviors like safety under downstream adaptation, addressing the brittleness of standard RLHF objectives.
Abstract: Large language models are commonly trained through multi-stage post-training: first via RLHF, then fine-tuned for other downstream objectives. Yet even small downstream updates can compromise earlier learned behaviors (e.g., safety), exposing a brittleness known as catastrophic forgetting. This suggests standard RLHF objectives do not guarantee robustness to future adaptation. To address it, most prior work designs downstream-time methods to preserve previously learned behaviors. We argue that preventing this requires pre-finetuning robustness: the base policy should avoid brittle high-reward solutions whose reward drops sharply under standard fine-tuning. We propose Fine-tuning Robust Policy Optimization (FRPO), a robust RLHF framework that optimizes reward not only at the current policy, but across a KL-bounded neighborhood of policies reachable by downstream adaptation. The key idea is to ensure reward stability under policy shifts via a max-min formulation. By modifying GRPO, we develop an algorithm with no extra computation, and empirically show it substantially reduces safety degradation across multiple base models and downstream fine-tuning regimes (SFT and RL) while preserving downstream task performance. We further study a math-focused RL setting, demonstrating that FRPO preserves accuracy under subsequent fine-tuning.
[947] Breaking the Simplification Bottleneck in Amortized Neural Symbolic Regression
Paul Saegert, Ullrich Köthe
Main category: cs.LG
TL;DR: SimpliPy: A fast rule-based simplification engine for symbolic regression that achieves 100x speed-up over SymPy, enabling improved amortized SR scalability and performance.
Details
Motivation: Amortized symbolic regression struggles with scaling to realistic scientific complexity due to slow equivalent expression reduction using general-purpose Computer Algebra Systems like SymPy, which severely limits training and inference speed.Method: Proposes SimpliPy, a rule-based simplification engine that achieves 100-fold speed-up over SymPy at comparable quality. This enables Flash-ANSR framework with improved scalability, more efficient token budget use, and systematic training set decontamination.
Result: Flash-ANSR achieves much better accuracy than amortized baselines (NeSymReS, E2E) on FastSRB benchmark and performs on par with state-of-the-art direct optimization (PySR) while recovering more concise expressions with increasing inference budget.
Conclusion: Fast simplification engines like SimpliPy enable substantial improvements in amortized symbolic regression, making it more scalable and efficient for realistic scientific applications.
Abstract: Symbolic regression (SR) aims to discover interpretable analytical expressions that accurately describe observed data. Amortized SR promises to be much more efficient than the predominant genetic programming SR methods, but currently struggles to scale to realistic scientific complexity. We find that a key obstacle is the lack of a fast reduction of equivalent expressions to a concise normalized form. Amortized SR has addressed this by general-purpose Computer Algebra Systems (CAS) like SymPy, but the high computational cost severely limits training and inference speed. We propose SimpliPy, a rule-based simplification engine achieving a 100-fold speed-up over SymPy at comparable quality. This enables substantial improvements in amortized SR, including scalability to much larger training sets, more efficient use of the per-expression token budget, and systematic training set decontamination with respect to equivalent test expressions. We demonstrate these advantages in our Flash-ANSR framework, which achieves much better accuracy than amortized baselines (NeSymReS, E2E) on the FastSRB benchmark. Moreover, it performs on par with state-of-the-art direct optimization (PySR) while recovering more concise instead of more complex expressions with increasing inference budget.
[948] Kirin: Improving ANN efficiency with SNN Hybridization
Chenyu Wang, Zhanglu Yan, Zhi Zhou, Xu Chen, Weng-Fai Wong
Main category: cs.LG
TL;DR: Kirin proposes a hybrid integer-spike SNN approach for accurate ANN-to-SNN conversion with improved time and energy efficiency by combining binary spikes for low-bit parameters with integer preservation for others, plus a silence threshold mechanism.
Details
Motivation: Traditional ANN-to-SNN conversion faces challenges: high bit-width quantization requires long time windows (increasing latency), and there's a trade-off between information loss in single-spike schemes vs energy costs in multi-spike schemes. Need for accuracy-preserving, time- and energy-efficient conversion.Method: 1) Spike Matrix Hybridization: encodes low bit-width parameters into binary spikes (small time window) while preserving higher-bit parameters in integer format. 2) Silence threshold mechanism: regulates single-spike firing timing to ensure mathematical equivalence with LLM outputs and preserve accuracy.
Result: Under W4A4&8 quantization, achieves near-FP16 accuracy while reducing energy consumption by up to 84.66% and shortening time steps by 93.75% compared to traditional approaches.
Conclusion: Kirin enables accurate ANN-to-SNN conversion with significant improvements in both time and energy efficiency, addressing key limitations of existing conversion methods through hybrid integer-spike representation and timing regulation.
Abstract: Artificial neural networks (ANNs), particularly large language models (LLMs), demonstrate powerful inference capabilities but consume substantial energy. Conversely, spiking neural networks (SNNs) exhibit exceptional energy efficiency due to their binary and event-driven characteristics, thus motivating the study of ANN-to-SNN conversion. In this process, quantization plays a pivotal role, mapping LLMs’ floating-point parameters to discrete SNN parameters via the temporal dimension of the time window. However, several challenges remain in the conversion process: (i) converting high bit-width quantization values into binary spikes requires longer time windows, increasing system latency; and (ii) the inherent trade-off between the information loss of single-spike schemes and the energy costs of multi-spike ones in SNN. To address these challenges, we propose Kirin, a integer and spike hybrid based SNN to achieve accuracy lossless ANN-to-SNN conversion with time and energy efficiency. Specifically, we first propose a Spike Matrix Hybridization strategy that encoding low bit-width parameters that leading to small time window size into binary spikes while preserving the rest in integer format, thereby reducing the overall latency of SNN execution. Second, we introduce a silence threshold mechanism to regulate the timing of single-spike firing, ensuring the output is mathematically equivalent to the LLM’s output and preserves accuracy. Experimental results demonstrate that Kirin, under a W4A4&8 quantization setting, achieves near-FP16 accuracy while reducing energy consumption by up to 84.66% and shortening time steps by 93.75%.
[949] FlexMoRE: A Flexible Mixture of Rank-heterogeneous Experts for Efficient Federatedly-trained Large Language Models
Annemette Brok Pirchert, Jacob Nielsen, Mogens Henrik From, Lukas Galke Poech, Peter Schneider-Kamp
Main category: cs.LG
TL;DR: FlexMoRE introduces a flexible mixture of rank-heterogeneous experts where experts can be either full-sized models or low-rank adapters, enabling memory-efficient multimodal learning while maintaining performance.
Details
Motivation: To address the memory inefficiency of full-sized experts in mixture-of-experts architectures by exploring whether low-rank adapters can sufficiently capture domain knowledge while reducing parameter count.Method: Developed FlexMoRE with flexible mixture of rank-heterogeneous experts (full-sized or low-rank adapters), systematically evaluated 6 experts with ranks from 2^0 to 2^14 across 150 mixtures and 120 tasks, using FlexOlmo as base architecture.
Result: Found that optimal expert rank varies by task type (higher for reasoning-heavy vs knowledge-heavy benchmarks), achieving better performance (47.18 avg score) than full-sized expert baseline (45.46) with <1/3 parameters (10.75B vs 33.27B).
Conclusion: Low-rank adapters can effectively replace full-sized experts in mixture-of-experts architectures, offering significant memory savings without performance loss, with rank sensitivity varying by task type.
Abstract: Recent advances in mixture-of-experts architectures have shown that individual experts models can be trained federatedly, i.e., in isolation from other experts by using a common base model to facilitate coordination. However, we hypothesize that full-sized experts may not be necessary for all domains and that instead low-rank adapters may be sufficient. Here, we introduce FlexMoRE, a Flexible Mixture of Rank-heterogenous Experts, which may be either full-sized experts or adapters of a suitable rank. We systematically investigate the trade-off between expert rank and downstream task performance by evaluating $6$ experts with ranks $2^0$ to $2^{14}$ resulting in experiments covering 150 mixtures (96 with 2 experts, 54 with 7 experts) that are evaluated across $120$ tasks. For our experiments, we build on FlexOlmo and turn its pre-trained experts into low-rank versions. Our regression analysis from expert rank to downstream task performance reveals that the best-performing rank is substantially higher for reasoning-heavy benchmarks than for knowledge-heavy benchmarks. These findings on rank sensitivity come with direct implications for memory efficiency: Using optimal ranks, FlexMoRE yields improved downstream task performance (average score $47.18$) compared to the baseline FlexOlmo-style mixture of full-sized experts (average score $45.46$) at less than one third the parameters ($10.75$B for FlexMoRE vs. $33.27$B for FlexOlmo). All code will be made available.
[950] Rethinking Graph Generalization through the Lens of Sharpness-Aware Minimization
Yang Qiu, Yixiong Zou, Jun Wang
Main category: cs.LG
TL;DR: Paper proposes E2A framework using energy-based generative augmentation to address Minimal Shift Flip phenomenon in Graph Neural Networks for improved OOD generalization.
Details
Motivation: GNNs are sensitive to distribution shifts, particularly Minimal Shift Flip where test samples slightly deviating from training distribution are abruptly misclassified. Need to understand and address this phenomenon for better graph generalization.Method: Revisit MSF through Sharpness-Aware Minimization lens, introduce Local Robust Radius concept, develop energy-based formulation correlated with robust radius, and propose energy-driven generative augmentation framework (E2A) using energy-guided latent perturbations to generate pseudo-OOD samples.
Result: Extensive experiments across multiple benchmarks show E2A consistently improves graph OOD generalization, outperforming state-of-the-art baselines.
Conclusion: E2A framework effectively addresses MSF phenomenon and enhances GNN generalization through principled energy-based augmentation approach.
Abstract: Graph Neural Networks (GNNs) have achieved remarkable success across various graph-based tasks but remain highly sensitive to distribution shifts. In this work, we focus on a prevalent yet under-explored phenomenon in graph generalization, Minimal Shift Flip (MSF),where test samples that slightly deviate from the training distribution are abruptly misclassified. To interpret this phenomenon, we revisit MSF through the lens of Sharpness-Aware Minimization (SAM), which characterizes the local stability and sharpness of the loss landscape while providing a theoretical foundation for modeling generalization error. To quantify loss sharpness, we introduce the concept of Local Robust Radius, measuring the smallest perturbation required to flip a prediction and establishing a theoretical link between local stability and generalization. Building on this perspective, we further observe a continual decrease in the robust radius during training, indicating weakened local stability and an increasingly sharp loss landscape that gives rise to MSF. To jointly solve the MSF phenomenon and the intractability of radius, we develop an energy-based formulation that is theoretically proven to be monotonically correlated with the robust radius, offering a tractable and principled objective for modeling flatness and stability. Building on these insights, we propose an energy-driven generative augmentation framework (E2A) that leverages energy-guided latent perturbations to generate pseudo-OOD samples and enhance model generalization. Extensive experiments across multiple benchmarks demonstrate that E2A consistently improves graph OOD generalization, outperforming state-of-the-art baselines.
[951] Dist2ill: Distributional Distillation for One-Pass Uncertainty Estimation in Large Language Models
Yicong Zhao, King Yeung Tsang, Harshil Vejendla, Haizhou Shi, Zhuohang Li, Zhigang Hua, Qi Xu, Tunyu Zhang, Yi Wang, Ligong Han, Bradley A. Malin, Hao Wang
Main category: cs.LG
TL;DR: Dist2ill: A distributional distillation framework that enables accurate uncertainty estimation in LLMs with single forward pass by training models to produce diverse reasoning paths and approximating confidence scores.
Details
Motivation: LLMs often have misalignment between response quality and confidence estimates. Bayesian methods provide better uncertainty estimation but are computationally expensive due to repeated sampling at test time.Method: Proposes Dist2ill framework that trains LLMs to produce multiple diverse reasoning paths in one inference pass, using a lightweight parametric module to approximate empirical confidence scores from sampling distribution.
Result: Achieves state-of-the-art uncertainty estimation, substantially improving Expected Calibration Error (ECE) and Negative Log-Likelihood (NLL) while maintaining computational efficiency.
Conclusion: Dist2ill enables accurate uncertainty estimation in LLMs with single forward pass, preserving reasoning diversity while being computationally efficient compared to Bayesian methods.
Abstract: Large Language Models (LLMs) often exhibit misalignment between the quality of their generated responses and the confidence estimates they assign to them. Bayesian treatments, such as marginalizing over a reliable weight posterior or over the space of reasoning traces, provide an effective remedy, but incur substantial computational overhead due to repeated sampling at test time. To enable accurate uncertainty estimation in a single forward pass, we propose a novel distributional distillation framework (Dist2ill) that trains an LLM to produce multiple diverse reasoning paths within one inference pass, while using a lightweight parametric module to approximate empirical confidence scores derived from the sampling distribution. Extensive experiments demonstrate that Dist2ill preserves reasoning diversity and achieves state-of-the-art uncertainty estimation, substantially improving Expected Calibration Error (ECE) and Negative Log-Likelihood (NLL), while remaining computationally efficient.
[952] Magnitude Distance: A Geometric Measure of Dataset Similarity
Sahel Torkamani, Henry Gouk, Rik Sarkar
Main category: cs.LG
TL;DR: Magnitude distance is a novel metric for comparing datasets using metric space magnitude theory, with tunable scaling parameter for sensitivity to global vs local structure, proven theoretical properties, and applications in generative modeling.
Details
Motivation: The paper addresses the fundamental problem of quantifying distances between datasets in mathematics and machine learning, seeking a distance metric that remains discriminative in high-dimensional settings and can capture both global structure and finer details.Method: Proposes magnitude distance based on the concept of magnitude of a metric space, with a tunable scaling parameter t that controls sensitivity to global structure (small t) vs finer details (large t). Proves theoretical properties including limiting behavior and metric conditions, and demonstrates its use as training objective for push-forward generative models.
Result: Theoretical analysis shows magnitude distance remains discriminative in high-dimensional settings when scale is appropriately tuned. Experimental results demonstrate it provides meaningful signals comparable to established distance-based generative approaches.
Conclusion: Magnitude distance is a theoretically grounded, tunable metric for dataset comparison that maintains discriminative power in high dimensions and shows promise as a training objective for generative models.
Abstract: Quantifying the distance between datasets is a fundamental question in mathematics and machine learning. We propose \textit{magnitude distance}, a novel distance metric defined on finite datasets using the notion of the \emph{magnitude} of a metric space. The proposed distance incorporates a tunable scaling parameter, $t$, that controls the sensitivity to global structure (small $t$) and finer details (large $t$). We prove several theoretical properties of magnitude distance, including its limiting behavior across scales and conditions under which it satisfies key metric properties. In contrast to classical distances, we show that magnitude distance remains discriminative in high-dimensional settings when the scale is appropriately tuned. We further demonstrate how magnitude distance can be used as a training objective for push-forward generative models. Our experimental results support our theoretical analysis and demonstrate that magnitude distance provides meaningful signals, comparable to established distance-based generative approaches.
[953] Safety Subspaces are Not Linearly Distinct: A Fine-Tuning Case Study
Kaustubh Ponkshe, Shaan Shah, Raghav Singhal, Praneeth Vepakomma
Main category: cs.LG
TL;DR: Safety alignment in LLMs is entangled with general learning, not isolated in distinct subspaces, challenging subspace-based defense approaches.
Details
Motivation: Safety alignment in LLMs is known to be brittle and can degrade during fine-tuning. Previous work suggests safety may correspond to identifiable directions in weight space that could be isolated for defense, but this needs empirical validation.Method: Comprehensive empirical study examining whether safety-relevant behavior is concentrated in specific linear subspaces, whether it can be separated from general-purpose learning, and whether harmfulness arises from distinguishable activation patterns. Experiments conducted on five open-source LLMs from Llama and Qwen families.
Result: Findings show safety is highly entangled with general learning components: subspaces that amplify safe behaviors also amplify useful ones, and prompts with different safety implications activate overlapping representations. Safety does not reside in distinct directions.
Conclusion: Subspace-based defenses face fundamental limitations due to the entanglement of safety with general learning. Alternative strategies are needed to preserve safety under continued training.
Abstract: Large Language Models (LLMs) rely on safety alignment to produce socially acceptable responses. However, this behavior is known to be brittle: further fine-tuning, even on benign or lightly contaminated data, can degrade safety and reintroduce harmful behaviors. A growing body of work suggests that alignment may correspond to identifiable directions in weight space, forming subspaces that could, in principle, be isolated or preserved to defend against misalignment. In this work, we conduct a comprehensive empirical study of this perspective. We examine whether safety-relevant behavior is concentrated in specific linear subspaces, whether it can be separated from general-purpose learning, and whether harmfulness arises from distinguishable patterns in activations. Across both weight and activation spaces, our findings are consistent: subspaces that amplify safe behaviors also amplify useful ones, and prompts with different safety implications activate overlapping representations. Rather than residing in distinct directions, we show that safety is highly entangled with the general learning components of the model. This suggests that subspace-based defenses face fundamental limitations and underscores the need for alternative strategies to preserve safety under continued training. We corroborate these findings with multiple experiments on five open-source LLMs from the Llama and Qwen families. Our code is publicly available at: https://github.com/CERT-Lab/safety-subspaces.
[954] Near-optimal Swap Regret Minimization for Convex Losses
Lunjia Hu, Jon Schneider, Yifan Wu
Main category: cs.LG
TL;DR: Randomized online algorithm achieves near-optimal Õ(√T) swap regret for Lipschitz convex losses on unit interval, improving previous Õ(T^{2/3}) bound, with efficient poly(T) runtime and applications to calibration error minimization.
Details
Motivation: Addresses open question from Fishelson et al. [2025b] about improving swap regret bounds for online learning with Lipschitz convex losses, with applications to calibration error minimization for general elicitable properties.Method: Uses multi-scale binning technique: discretizes unit interval into bins at multiple granularity scales and simultaneously uses all scales to make randomized predictions. The algorithm is randomized and runs in polynomial time.
Result: Achieves Õ(√T) expected swap regret, improving previous Õ(T^{2/3}) bound. Provides efficient algorithm for minimizing calibration error without Lipschitzness assumption, enabling first Õ(√T) calibration error guarantee for median calibration.
Conclusion: Develops novel multi-scale binning technique to achieve near-optimal swap regret bounds, answering open question and providing efficient calibration algorithms with broader applicability.
Abstract: We give a randomized online algorithm that guarantees near-optimal $\widetilde O(\sqrt T)$ expected swap regret against any sequence of $T$ adaptively chosen Lipschitz convex losses on the unit interval. This improves the previous best bound of $\widetilde O(T^{2/3})$ and answers an open question of Fishelson et al. [2025b]. In addition, our algorithm is efficient: it runs in $\mathsf{poly}(T)$ time. A key technical idea we develop to obtain this result is to discretize the unit interval into bins at multiple scales of granularity and simultaneously use all scales to make randomized predictions, which we call multi-scale binning and may be of independent interest. A direct corollary of our result is an efficient online algorithm for minimizing the calibration error for general elicitable properties. This result does not require the Lipschitzness assumption of the identification function needed in prior work, making it applicable to median calibration, for which we achieve the first $\widetilde O(\sqrt T)$ calibration error guarantee.
[955] StealthRL: Reinforcement Learning Paraphrase Attacks for Multi-Detector Evasion of AI-Text Detectors
Suraj Ranganath, Atharv Ramesh
Main category: cs.LG
TL;DR: StealthRL is a reinforcement learning framework that stress-tests AI-text detector robustness using adversarial paraphrasing attacks, achieving near-perfect evasion while preserving semantics.
Details
Motivation: AI-text detectors face critical robustness challenges from adversarial paraphrasing attacks that preserve semantics while evading detection, exposing vulnerabilities in current detection systems.Method: StealthRL trains a paraphrase policy using Group Relative Policy Optimization (GRPO) with LoRA adapters on Qwen3-4B against a multi-detector ensemble, optimizing a composite reward balancing detector evasion with semantic preservation.
Result: Achieves near-zero detection (0.001 mean TPR@1%FPR), reduces mean AUROC from 0.74 to 0.27, 99.9% attack success rate, and transfers to held-out detectors, revealing shared architectural vulnerabilities.
Conclusion: Exposes significant robustness gaps in current AI-text detection and establishes StealthRL as a principled adversarial evaluation protocol for detector robustness testing.
Abstract: AI-text detectors face a critical robustness challenge: adversarial paraphrasing attacks that preserve semantics while evading detection. We introduce StealthRL, a reinforcement learning framework that stress-tests detector robustness under realistic adversarial conditions. StealthRL trains a paraphrase policy against a multi-detector ensemble using Group Relative Policy Optimization (GRPO) with LoRA adapters on Qwen3-4B, optimizing a composite reward that balances detector evasion with semantic preservation. We evaluate six attack settings (M0-M5) against three detector families (RoBERTa, FastDetectGPT, and Binoculars) at the security-relevant 1% false positive rate operating point. StealthRL achieves near-zero detection (0.001 mean TPR@1%FPR), reduces mean AUROC from 0.74 to 0.27, and attains a 99.9% attack success rate. Critically, attacks transfer to a held-out detector family not seen during training, revealing shared architectural vulnerabilities rather than detector-specific brittleness. We additionally conduct LLM-based quality evaluation via Likert scoring, analyze detector score distributions to explain why evasion succeeds, and provide per-detector AUROC with bootstrap confidence intervals. Our results expose significant robustness gaps in current AI-text detection and establish StealthRL as a principled adversarial evaluation protocol. Code and evaluation pipeline are publicly available at https://github.com/suraj-ranganath/StealthRL.
[956] Stress-Testing Alignment Audits With Prompt-Level Strategic Deception
Oliver Daniels, Perusha Moodley, Ben Marlin, David Lindner
Main category: cs.LG
TL;DR: Automatic red-team pipeline generates deception strategies to stress-test alignment auditing methods, revealing vulnerabilities in both black-box and white-box approaches against strategic misaligned models.
Details
Motivation: Existing alignment auditing methods haven't been systematically tested against deception strategies from situationally aware misaligned models, creating a gap in understanding their robustness against strategic threats.Method: Developed an automatic red-team pipeline that generates tailored deception strategies (system prompts) to stress-test specific white-box and black-box auditing methods including assistant prefills, user persona sampling, sparse autoencoders, and token embedding similarity.
Result: The pipeline successfully found prompts that deceived both black-box and white-box methods into making confident, incorrect guesses, providing the first documented evidence of activation-based strategic deception.
Conclusion: Current black-box and white-box auditing methods would not be robust against sufficiently capable misaligned models, highlighting the need for more resilient alignment verification approaches.
Abstract: Alignment audits aim to robustly identify hidden goals from strategic, situationally aware misaligned models. Despite this threat model, existing auditing methods have not been systematically stress-tested against deception strategies. We address this gap, implementing an automatic red-team pipeline that generates deception strategies (in the form of system prompts) tailored to specific white-box and black-box auditing methods. Stress-testing assistant prefills, user persona sampling, sparse autoencoders, and token embedding similarity methods against secret-keeping model organisms, our automatic red-team pipeline finds prompts that deceive both the black-box and white-box methods into confident, incorrect guesses. Our results provide the first documented evidence of activation-based strategic deception, and suggest that current black-box and white-box methods would not be robust to a sufficiently capable misaligned model.
[957] Discrete Bridges for Mutual Information Estimation
Iryna Zabarianska, Sergei Kholkin, Grigoriy Ksenofontov, Ivan Butakov, Alexander Korotin
Main category: cs.LG
TL;DR: Proposes DBMI estimator using discrete diffusion bridge models to estimate mutual information between discrete random variables, framing MI estimation as domain transfer problem.
Details
Motivation: Existing mutual information estimators struggle with discrete data. Discrete diffusion bridge models offer a promising framework for discrete MI estimation by treating it as a domain transfer problem.Method: Leverages discrete state space formulation of bridge matching models to construct Discrete Bridge Mutual Information (DBMI) estimator. Frames MI estimation as domain transfer between marginal distributions.
Result: Demonstrates performance on low-dimensional and image-based MI estimation settings, showing effectiveness for discrete data where conventional estimators face difficulties.
Conclusion: Discrete diffusion bridge models provide a novel and effective approach for mutual information estimation in discrete domains, addressing limitations of existing methods.
Abstract: Diffusion bridge models in both continuous and discrete state spaces have recently become powerful tools in the field of generative modeling. In this work, we leverage the discrete state space formulation of bridge matching models to address another important problem in machine learning and information theory: the estimation of the mutual information (MI) between discrete random variables. By neatly framing MI estimation as a domain transfer problem, we construct a Discrete Bridge Mutual Information (DBMI) estimator suitable for discrete data, which poses difficulties for conventional MI estimators. We showcase the performance of our estimator on two MI estimation settings: low-dimensional and image-based.
[958] Can We Infer Confidential Properties of Training Data from LLMs?
Pengrun Huang, Chhavi Yadav, Kamalika Chaudhuri, Ruihan Wu
Main category: cs.LG
TL;DR: PropInfer: A benchmark for evaluating property inference attacks on fine-tuned LLMs, showing they can leak sensitive dataset-level properties like patient demographics.
Details
Motivation: LLMs are increasingly fine-tuned on domain-specific datasets containing sensitive properties (patient demographics, disease prevalence). While property inference attacks have been studied for discriminative models and GANs, it's unclear if they transfer to LLMs, creating a security gap.Method: Introduces PropInfer benchmark built on ChatDoctor dataset with various property types and task configurations. Proposes two attacks: 1) prompt-based generation attack, and 2) shadow-model attack leveraging word frequency signals. Evaluates across multiple pretrained LLMs.
Result: Empirical evaluations show successful property inference attacks on LLMs, revealing a previously unrecognized vulnerability where fine-tuned LLMs can leak sensitive dataset-level properties.
Conclusion: LLMs are vulnerable to property inference attacks, exposing sensitive dataset properties. This highlights security risks in domain-specific LLM applications and the need for better privacy protection mechanisms.
Abstract: Large language models (LLMs) are increasingly fine-tuned on domain-specific datasets to support applications in fields such as healthcare, finance, and law. These fine-tuning datasets often have sensitive and confidential dataset-level properties – such as patient demographics or disease prevalence – that are not intended to be revealed. While prior work has studied property inference attacks on discriminative models (e.g., image classification models) and generative models (e.g., GANs for image data), it remains unclear if such attacks transfer to LLMs. In this work, we introduce PropInfer, a benchmark task for evaluating property inference in LLMs under two fine-tuning paradigms: question-answering and chat-completion. Built on the ChatDoctor dataset, our benchmark includes a range of property types and task configurations. We further propose two tailored attacks: a prompt-based generation attack and a shadow-model attack leveraging word frequency signals. Empirical evaluations across multiple pretrained LLMs show the success of our attacks, revealing a previously unrecognized vulnerability in LLMs.
[959] StretchTime: Adaptive Time Series Forecasting via Symplectic Attention
Yubin Kim, Viresh Pati, Jevon Twitty, Vinh Pham, Shihao Yang, Jiecheng Lu
Main category: cs.LG
TL;DR: SyPE (Symplectic Positional Embeddings) replaces RoPE with learnable symplectic transformations to handle time-warped dynamics in time series forecasting, implemented in StretchTime architecture.
Details
Motivation: Real-world systems often exhibit "time-warped" dynamics where temporal progression doesn't align with uniform sampling indices, but standard positional encodings like RoPE can't represent non-affine temporal warping.Method: Proposes SyPE that extends RoPE’s rotation group SO(2) to symplectic group Sp(2,R) with input-dependent adaptive warp module, allowing attention to adaptively dilate/contract temporal coordinates end-to-end.
Result: StretchTime architecture with SyPE achieves state-of-the-art performance on standard benchmarks and demonstrates superior robustness on datasets with non-stationary temporal dynamics.
Conclusion: SyPE provides a principled solution for handling time-warped dynamics in transformer-based time series forecasting, strictly generalizing RoPE while capturing locally varying periodicities.
Abstract: Transformer architectures have established strong baselines in time series forecasting, yet they typically rely on positional encodings that assume uniform, index-based temporal progression. However, real-world systems, from shifting financial cycles to elastic biological rhythms, frequently exhibit “time-warped” dynamics where the effective flow of time decouples from the sampling index. In this work, we first formalize this misalignment and prove that rotary position embedding (RoPE) is mathematically incapable of representing non-affine temporal warping. To address this, we propose Symplectic Positional Embeddings (SyPE), a learnable encoding framework derived from Hamiltonian mechanics. SyPE strictly generalizes RoPE by extending the rotation group $\mathrm{SO}(2)$ to the symplectic group $\mathrm{Sp}(2,\mathbb{R})$, modulated by a novel input-dependent adaptive warp module. By allowing the attention mechanism to adaptively dilate or contract temporal coordinates end-to-end, our approach captures locally varying periodicities without requiring pre-defined warping functions. We implement this mechanism in StretchTime, a multivariate forecasting architecture that achieves state-of-the-art performance on standard benchmarks, demonstrating superior robustness on datasets exhibiting non-stationary temporal dynamics.
[960] GSS: Gated Subspace Steering for Selective Memorization Mitigation in LLMs
Xuanqi Zhang, Haoyang Shang, Xiaoxiao Li
Main category: cs.LG
TL;DR: Gated Subspace Steering (GSS) is a selective memorization mitigation method that uses context-aware intervention to reduce LLM memorization without degrading normal generalization performance.
Details
Motivation: Current memorization mitigation methods apply interventions uniformly, which degrades performance on tokens that generalize normally. Memorization is sparse, intermittent, and token-conditioned, requiring targeted rather than uniform intervention.Method: GSS decomposes intervention into a probe (detecting memorization-relevant activations) and a steer (applying targeted correction only when probe exceeds threshold). The optimal probe-steer pair emerges from a principled optimization framework based on optimal subspace steering.
Result: Experiments on four benchmarks show GSS matches or exceeds state-of-the-art memorization reduction while requiring 100-1000× less compute than optimization-based alternatives.
Conclusion: GSS provides an effective selective memorization mitigation method with new theoretical insights into the geometry of memorization in neural representations.
Abstract: Large language models (LLMs) can memorize and reproduce training sequences verbatim – a tendency that undermines both generalization and privacy. Existing mitigation methods apply interventions uniformly, degrading performance on the majority of tokens that generalize normally. We show empirically that memorization is sparse, intermittent, and token-conditioned, suggesting that effective mitigation requires context-aware intervention rather than static parameter modification. To this end, we propose a novel and effective selective memorization mitigation method – Gated Subspace Steering (GSS), which decomposes intervention into a probe (detecting memorization-relevant activations) and a steer (applying targeted correction only when the probe exceeds a threshold). The optimal probe-steer pair emerges from a principled optimization framework based on optimal subspace steering. Experiments on four benchmarks show GSS matches or exceeds state-of-the-art memorization reduction while requiring $100-1000 \times$ less compute than optimization-based alternatives. Furthermore, we provide new theoretical insights into the geometry of memorization in neural representations.
[961] Benchmarking Large Language Models for Geolocating Colonial Virginia Land Grants
Ryan Mioduski
Main category: cs.LG
TL;DR: LLMs can convert historical land patent descriptions to geographic coordinates with 23km mean error, outperforming traditional methods and offering cost-effective historical georeferencing.
Details
Motivation: Historical land patents exist as narrative descriptions that limit spatial analysis; need automated methods to convert prose to geographic coordinates for historical GIS applications.Method: Evaluated 6 OpenAI LLMs across 3 architectures on 5,471 Virginia patent abstracts using direct-to-coordinate and tool-augmented chain-of-thought approaches, compared against GIS analyst baseline and other geoparsers.
Result: Best model (o3-2025-04-16) achieved 23km mean error (14km median), outperforming baselines by 67-70%; ensemble reduced to 19.2km mean error; cost-effective at ~$0.20 per grant.
Conclusion: LLMs enable scalable, accurate, cost-effective historical georeferencing, relying on textual descriptions rather than memorization, with ensemble approaches further improving accuracy.
Abstract: Virginia’s seventeenth- and eighteenth-century land patents survive primarily as narrative metes-and-bounds descriptions, limiting spatial analysis. This study systematically evaluates current-generation large language models (LLMs) in converting these prose abstracts into geographically accurate latitude/longitude coordinates within a focused evaluation context. A digitized corpus of 5,471 Virginia patent abstracts (1695-1732) is released, with 43 rigorously verified test cases serving as an initial, geographically focused benchmark. Six OpenAI models across three architectures-o-series, GPT-4-class, and GPT-3.5-were tested under two paradigms: direct-to-coordinate and tool-augmented chain-of-thought invoking external geocoding APIs. Results were compared against a GIS analyst baseline, Stanford NER geoparser, Mordecai-3 neural geoparser, and a county-centroid heuristic. The top single-call model, o3-2025-04-16, achieved a mean error of 23 km (median 14 km), outperforming the median LLM (37.4 km) by 37.5%, the weakest LLM (50.3 km) by 53.5%, and external baselines by 67% (GIS analyst) and 70% (Stanford NER). A five-call ensemble further reduced errors to 19.2 km (median 12.2 km) at minimal additional cost (~USD 0.20 per grant), outperforming the median LLM by 48.7%. A patentee-name redaction ablation slightly increased error (~7%), showing reliance on textual landmark and adjacency descriptions rather than memorization. The cost-effective gpt-4o-2024-08-06 model maintained a 28 km mean error at USD 1.09 per 1,000 grants, establishing a strong cost-accuracy benchmark. External geocoding tools offer no measurable benefit in this evaluation. These findings demonstrate LLMs’ potential for scalable, accurate, cost-effective historical georeferencing.
[962] Improving Detection of Rare Nodes in Hierarchical Multi-Label Learning
Isaac Xu, Martin Gillis, Ayushi Sharma, Benjamin Misiuk, Craig J. Brown, Thomas Trappenberg
Main category: cs.LG
TL;DR: Proposes weighted loss for hierarchical multi-label classification that combines node-wise imbalance weighting with focal weighting using ensemble uncertainties to improve recall of rare hierarchical nodes.
Details
Motivation: Hierarchical multi-label classification struggles with reaching deeper levels of hierarchy due to natural rarity of certain classes/nodes and hierarchical constraints where child nodes are less frequent than parents.Method: Weighted loss objective combining node-wise imbalance weighting with focal weighting components that leverage ensemble uncertainties, emphasizing rare nodes rather than rare observations and focusing on uncertain nodes for each model output distribution.
Result: Improvements in recall by up to factor of five on benchmark datasets, statistically significant gains in F1 score, and helps convolutional networks in challenging tasks with suboptimal encoders or limited data.
Conclusion: The proposed weighted loss approach effectively addresses hierarchical class imbalance by focusing on rare nodes and uncertain predictions, leading to substantial improvements in hierarchical classification performance.
Abstract: In hierarchical multi-label classification, a persistent challenge is enabling model predictions to reach deeper levels of the hierarchy for more detailed or fine-grained classifications. This difficulty partly arises from the natural rarity of certain classes (or hierarchical nodes) and the hierarchical constraint that ensures child nodes are almost always less frequent than their parents. To address this, we propose a weighted loss objective for neural networks that combines node-wise imbalance weighting with focal weighting components, the latter leveraging modern quantification of ensemble uncertainties. By emphasizing rare nodes rather than rare observations (data points), and focusing on uncertain nodes for each model output distribution during training, we observe improvements in recall by up to a factor of five on benchmark datasets, along with statistically significant gains in $F_{1}$ score. We also show our approach aids convolutional networks on challenging tasks, as in situations with suboptimal encoders or limited data.
[963] Positive Distribution Shift as a Framework for Understanding Tractable Learning
Marko Medvedev, Idan Attias, Elisabetta Cornacchia, Theodor Misiakiewicz, Gal Vardi, Nathan Srebro
Main category: cs.LG
TL;DR: The paper introduces Positive Distribution Shift (PDS), arguing that carefully chosen training distributions can make learning computationally easier rather than harder, contrary to traditional views of distribution shift as harmful.
Details
Motivation: Traditional distribution shift literature views covariate shift as harmful to learning, but the authors argue that with well-chosen training distributions, shift can actually make learning easier and more computationally tractable.Method: The authors formalize different variants of Positive Distribution Shift (PDS), analyze how certain hard function classes become easily learnable under PDS, and make connections with membership query learning.
Result: The paper shows that PDS can transform computationally hard learning problems into tractable ones using standard gradient-based training, demonstrating that distribution shift can be beneficial rather than harmful.
Conclusion: Positive Distribution Shift offers a new perspective where carefully designed training distributions can significantly improve learning efficiency, particularly for computationally challenging problems.
Abstract: We study a setting where the goal is to learn a target function f(x) with respect to a target distribution D(x), but training is done on i.i.d. samples from a different training distribution D’(x), labeled by the true target f(x). Such a distribution shift (here in the form of covariate shift) is usually viewed negatively, as hurting or making learning harder, and the traditional distribution shift literature is mostly concerned with limiting or avoiding this negative effect. In contrast, we argue that with a well-chosen D’(x), the shift can be positive and make learning easier – a perspective called Positive Distribution Shift (PDS). Such a perspective is central to contemporary machine learning, where much of the innovation is in finding good training distributions D’(x), rather than changing the training algorithm. We further argue that the benefit is often computational rather than statistical, and that PDS allows computationally hard problems to become tractable even using standard gradient-based training. We formalize different variants of PDS, show how certain hard classes are easily learnable under PDS, and make connections with membership query learning.
[964] SNAP-UQ: Self-supervised Next-Activation Prediction for Single-Pass Uncertainty in TinyML
Ismail Lamaakal, Chaymae Yahyati, Khalid El Makkaoui, Ibrahim Ouahbi, Yassine Maleh
Main category: cs.LG
TL;DR: SNAP-UQ: A single-pass, label-free uncertainty estimation method for TinyML that predicts next activations using tiny int8 heads, providing reliable uncertainty scores with minimal resource overhead.
Details
Motivation: Current uncertainty estimation methods (ensembles, MC dropout, early exits) are impractical for TinyML due to multiple passes, extra branches, or state requirements that exceed strict flash/latency budgets of microcontrollers.Method: Uses depth-wise next-activation prediction: taps backbone layers with tiny int8 heads to predict mean/scale of next activation from low-rank projection of previous activation. Standardized prediction error forms surprisal signal aggregated through lightweight monotone calibrator into uncertainty score.
Result: Reduces flash and latency by 40-60% smaller and 25-35% faster than early-exit/ensemble baselines. Improves accuracy-drop detection on corrupted streams by multiple AUPRC points, maintains strong failure detection (AUROC ≈0.9) in single forward pass.
Conclusion: SNAP-UQ offers resource-efficient uncertainty estimation for TinyML by grounding uncertainty in layer-to-layer dynamics rather than output confidence, enabling robust on-device monitoring with minimal overhead.
Abstract: Reliable uncertainty estimation is a key missing piece for on-device monitoring in TinyML: microcontrollers must detect failures, distribution shift, or accuracy drops under strict flash/latency budgets, yet common uncertainty approaches (deep ensembles, MC dropout, early exits, temporal buffering) typically require multiple passes, extra branches, or state that is impractical on milliwatt hardware. This paper proposes a novel and practical method, SNAP-UQ, for single-pass, label-free uncertainty estimation based on depth-wise next-activation prediction. SNAP-UQ taps a small set of backbone layers and uses tiny int8 heads to predict the mean and scale of the next activation from a low-rank projection of the previous one; the resulting standardized prediction error forms a depth-wise surprisal signal that is aggregated and mapped through a lightweight monotone calibrator into an actionable uncertainty score. The design introduces no temporal buffers or auxiliary exits and preserves state-free inference, while increasing deployment footprint by only a few tens of kilobytes. Across vision and audio backbones, SNAP-UQ reduces flash and latency relative to early-exit and deep-ensemble baselines (typically $\sim$40–60% smaller and $\sim$25–35% faster), with several competing methods at similar accuracy often exceeding MCU memory limits. On corrupted streams, it improves accuracy-drop event detection by multiple AUPRC points and maintains strong failure detection (AUROC $\approx 0.9$) in a single forward pass. By grounding uncertainty in layer-to-layer dynamics rather than solely in output confidence, SNAP-UQ offers a novel, resource-efficient basis for robust TinyML monitoring.
[965] GEMSS: A Variational Bayesian Method for Discovering Multiple Sparse Solutions in Classification and Regression Problems
Kateřina Henclová, Václav Šmídl
Main category: cs.LG
TL;DR: GEMSS is a variational Bayesian framework that discovers multiple diverse sparse feature combinations for interpretable feature selection in underdetermined, correlated regimes where conventional methods find only single solutions.
Details
Motivation: In underdetermined (n ≪ p) and highly correlated regimes, multiple distinct sparse feature subsets may equally explain responses, but conventional methods isolate single solutions, obscuring the full spectrum of plausible explanations needed for domain-specific insights.Method: Uses structured spike-and-slab prior for sparsity, mixture of Gaussians to approximate intractable multimodal posterior, and Jaccard-based penalty to control solution diversity. Optimizes entire ensemble of solutions within single objective function via stochastic gradient descent.
Result: Validated on 128 synthetic experiments across classification/regression tasks. Scales to high-dimensional settings (p=5000) with small samples (n=50), generalizes to continuous targets, handles missing data natively, robust to class imbalance and Gaussian noise.
Conclusion: GEMSS effectively discovers multiple diverse sparse solutions simultaneously, providing comprehensive interpretable feature sets for underdetermined problems, with practical implementation as Python package.
Abstract: Selecting interpretable feature sets in underdetermined ($n \ll p$) and highly correlated regimes constitutes a fundamental challenge in data science, particularly when analyzing physical measurements. In such settings, multiple distinct sparse subsets may explain the response equally well. Identifying these alternatives is crucial for generating domain-specific insights into the underlying mechanisms, yet conventional methods typically isolate a single solution, obscuring the full spectrum of plausible explanations. We present GEMSS (Gaussian Ensemble for Multiple Sparse Solutions), a variational Bayesian framework specifically designed to simultaneously discover multiple, diverse sparse feature combinations. The method employs a structured spike-and-slab prior for sparsity, a mixture of Gaussians to approximate the intractable multimodal posterior, and a Jaccard-based penalty to further control solution diversity. Unlike sequential greedy approaches, GEMSS optimizes the entire ensemble of solutions within a single objective function via stochastic gradient descent. The method is validated on a comprehensive benchmark comprising 128 synthetic experiments across classification and regression tasks. Results demonstrate that GEMSS scales effectively to high-dimensional settings ($p=5000$) with sample size as small as $n = 50$, generalizes seamlessly to continuous targets, handles missing data natively, and exhibits remarkable robustness to class imbalance and Gaussian noise. GEMSS is available as a Python package ‘gemss’ at PyPI. The full GitHub repository at https://github.com/kat-er-ina/gemss/ also includes a free, easy-to-use application suitable for non-coders.
[966] ARO: A New Lens On Matrix Optimization For Large Models
Wenbo Gong, Javier Zazo, Qijun Luo, Puqian Wang, James Hensman, Chao Ma
Main category: cs.LG
TL;DR: ARO is a new matrix optimization framework that uses gradient rotation as a core design principle, outperforming AdamW and orthogonalization methods in LLM pretraining with up to 8B parameters.
Details
Motivation: While matrix-based optimizers with orthogonalization/whitening methods have shown progress in improving LLM training efficiency, the authors question whether new paradigms beyond orthogonalization can push the efficiency frontier further.Method: ARO performs normed steepest descent in a rotated coordinate system where rotation is determined by a novel norm-informed policy. The framework treats gradient rotation as a first-class design principle and can be reformulated as a symmetry-aware optimizer grounded in rotational symmetries of residual streams.
Result: Under a rigorously controlled benchmarking protocol, ARO consistently outperforms AdamW (by 1.3-1.35×) and orthogonalization methods (by 1.1-1.15×) in LLM pretraining at up to 8B activated parameters and up to 8× overtrain budget, without evidence of diminishing returns.
Conclusion: ARO represents a new paradigm beyond orthogonalization for matrix optimization in LLM training, demonstrating significant efficiency gains and motivating advanced designs for computationally efficient exploitation of cross-layer/cross-module couplings.
Abstract: Matrix-based optimizers have attracted growing interest for improving LLM training efficiency, with significant progress centered on orthogonalization/whitening based methods. While yielding substantial performance gains, a fundamental question arises: can we develop new paradigms beyond orthogonalization, pushing the efficiency frontier further? We present \textbf{Adaptively Rotated Optimization (ARO}, a new matrix optimization framework that treats gradient rotation as a first class design principle. ARO accelerates LLM training by performing normed steepest descent in a rotated coordinate system, where the rotation is determined by a novel norm-informed policy. This perspective yields update rules that go beyond existing orthogonalization and whitening optimizers, improving sample efficiency in practice. To make comparisons reliable, we propose a rigorously controlled benchmarking protocol that reduces confounding and bias. Under this protocol, ARO consistently outperforms AdamW (by 1.3 $\sim$1.35$\times$) and orthogonalization methods (by 1.1$\sim$1.15$\times$) in LLM pretraining at up to 8B activated parameters, and up to $8\times$ overtrain budget, without evidence of diminishing returns. Finally, we discuss how ARO can be reformulated as a symmetry-aware optimizer grounded in rotational symmetries of residual streams, motivating advanced designs that enable computationally efficient exploitation of cross-layer/cross module couplings.
[967] Diffusion-Inspired Reconfiguration of Transformers for Uncertainty Calibration
Manh Cuong Dao, Quang Hung Pham, Phi Le Nguyen, Thao Nguyen Truong, Bryan Kian Hsiang Low, Trong Nghia Hoang
Main category: cs.LG
TL;DR: Proposes a diffusion-inspired probabilistic reconfiguration of transformers for better uncertainty calibration while maintaining original performance
Details
Motivation: Existing pre-trained transformers lack principled mechanisms for uncertainty propagation through their feature transformation stacks, which is critical for reliable deployment in risk-sensitive applicationsMethod: Models each transformer feature transformation block as a probabilistic mapping, composing them to create a probability path mimicking diffusion structure. This path is recompiled on a diffusion process with unified transition model to enable principled uncertainty propagation
Result: Superior calibration and predictive accuracy compared to existing uncertainty-aware transformers across various vision and language benchmarks
Conclusion: The diffusion-inspired probabilistic reconfiguration enables principled uncertainty propagation through transformer architectures while maintaining original predictive performance
Abstract: Uncertainty calibration in pre-trained transformers is critical for their reliable deployment in risk-sensitive applications. Yet, most existing pre-trained transformers do not have a principled mechanism for uncertainty propagation through their feature transformation stack. In this work, we propose a diffusion-inspired reconfiguration of transformers in which each feature transformation block is modeled as a probabilistic mapping. Composing these probabilistic mappings reveals a probability path that mimics the structure of a diffusion process, transporting data mass from the input distribution to the pre-trained feature distribution. This probability path can then be recompiled on a diffusion process with a unified transition model to enable principled propagation of representation uncertainty throughout the pre-trained model’s architecture while maintaining its original predictive performance. Empirical results across a variety of vision and language benchmarks demonstrate that our method achieves superior calibration and predictive accuracy compared to existing uncertainty-aware transformers.
[968] ANCRe: Adaptive Neural Connection Reassignment for Efficient Depth Scaling
Yilang Zhang, Bingcong Li, Niao He, Georgios B. Giannakis
Main category: cs.LG
TL;DR: ANCRe is a lightweight framework that learns optimal residual connection patterns from data, improving depth utilization and convergence in deep networks.
Details
Motivation: Deep layers in foundation models are often underutilized, and the default residual connection mechanism may not be optimal. The paper aims to improve depth efficiency by optimizing residual connectivity patterns.Method: Introduces Adaptive Neural Connection Reassignment (ANCRe), which parameterizes residual connectivities as learnable parameters. It reassigns connections with minimal overhead (<1%) by learning optimal connectivity patterns from data.
Result: Extensive tests show consistently accelerated convergence, boosted performance, and enhanced depth efficiency across large language models, diffusion models, and deep ResNets compared to conventional residual connections.
Conclusion: Residual connection layout fundamentally impacts convergence, and learning connectivity patterns from data can significantly improve depth utilization and training efficiency in deep neural networks.
Abstract: Scaling network depth has been a central driver behind the success of modern foundation models, yet recent investigations suggest that deep layers are often underutilized. This paper revisits the default mechanism for deepening neural networks, namely residual connections, from an optimization perspective. Rigorous analysis proves that the layout of residual connections can fundamentally shape convergence behavior, and even induces an exponential gap in convergence rates. Prompted by this insight, we introduce adaptive neural connection reassignment (ANCRe), a principled and lightweight framework that parameterizes and learns residual connectivities from the data. ANCRe adaptively reassigns residual connections with negligible computational and memory overhead ($<1%$), while enabling more effective utilization of network depth. Extensive numerical tests across pre-training of large language models, diffusion models, and deep ResNets demonstrate consistently accelerated convergence, boosted performance, and enhanced depth efficiency over conventional residual connections.
[969] DynamiQ: Accelerating Gradient Synchronization using Compressed Multi-hop All-reduce
Wenchen Han, Shay Vargaftik, Michael Mitzenmacher, Ran Ben Basat
Main category: cs.LG
TL;DR: DynamiQ is a quantization framework optimized for multi-hop all-reduce in large model training that improves gradient compression while maintaining near-baseline accuracy.
Details
Motivation: As training scale increases, network becomes bottleneck in multi-hop all-reduce operations. Existing gradient quantization systems are not optimized for multi-hop aggregation where entries are partially summed multiple times.Method: Introduces novel techniques to better represent partial sums in multi-hop aggregation, co-designed with a decompress-accumulate-recompress fused kernel for fast execution. Extended PyTorch DDP to support DynamiQ over NCCL P2P.
Result: Consistent improvement of up to 34.2% over state-of-the-art methods (Omni-Reduce, THC, MXFP4/6/8). Only method that consistently reaches near-baseline accuracy (99.9% of BF16 baseline) while significantly accelerating training.
Conclusion: DynamiQ effectively bridges the gap between quantization best practices and multi-hop aggregation, providing both performance acceleration and accuracy preservation for large-scale model training.
Abstract: Multi-hop all-reduce is the de facto backbone of large model training. As the training scale increases, the network often becomes a bottleneck, motivating reducing the volume of transmitted data. Accordingly, recent systems demonstrated significant acceleration of the training process using gradient quantization. However, these systems are not optimized for multi-hop aggregation, where entries are partially summed multiple times along their aggregation topology. This paper presents DynamiQ, a quantization framework that bridges the gap between quantization best practices and multi-hop aggregation. DynamiQ introduces novel techniques to better represent partial sums, co-designed with a decompress-accumulate-recompress fused kernel to facilitate fast execution. We extended PyTorch DDP to support DynamiQ over NCCL P2P, and across different LLMs, tasks, and scales, we demonstrate consistent improvement of up to 34.2% over the best among state-of-the-art methods such as Omni-Reduce, THC, and emerging standards such as MXFP4, MXFP6, and MXFP8. Further, DynamiQ is the only evaluated method that consistently reaches near-baseline accuracy (e.g., 99.9% of the BF16 baseline) and does so while significantly accelerating the training.
[970] Distributionally Robust Optimization via Generative Ambiguity Modeling
Jiaqi Wen, Jianyi Yang
Main category: cs.LG
TL;DR: Proposes GAS-DRO: Distributionally Robust Optimization using generative model-based ambiguity sets for improved OOD generalization
Details
Motivation: Need for DRO ambiguity sets that capture diverse adversarial distributions beyond nominal support while maintaining consistency with nominal distribution and leading to tractable solutionsMethod: Generative model-based ambiguity sets using parameterized generative models; GAS-DRO algorithm solves inner maximization over generative model space; implemented with diffusion models
Result: Formally established stationary convergence performance; empirically demonstrated superior Out-of-Distribution generalization performance in ML tasks
Conclusion: GAS-DRO provides tractable DRO solution with generative ambiguity sets that effectively enhance robustness and generalization
Abstract: This paper studies Distributionally Robust Optimization (DRO), a fundamental framework for enhancing the robustness and generalization of statistical learning and optimization. An effective ambiguity set for DRO must involve distributions that remain consistent to the nominal distribution while being diverse enough to account for a variety of potential scenarios. Moreover, it should lead to tractable DRO solutions. To this end, we propose generative model-based ambiguity sets that capture various adversarial distributions beyond the nominal support space while maintaining consistency with the nominal distribution. Building on this generative ambiguity modeling, we propose DRO with Generative Ambiguity Set (GAS-DRO), a tractable DRO algorithm that solves the inner maximization over the parameterized generative model space. We formally establish the stationary convergence performance of GAS-DRO. We implement GAS-DRO with a diffusion model and empirically demonstrate its superior Out-of-Distribution (OOD) generalization performance in ML tasks.
[971] DirMoE: Dirichlet-routed Mixture of Experts
Amirhossein Vahidi, Hesam Asadollahzadeh, Navid Akhavan Attar, Marie Moullet, Kevin Ly, Xingyi Yang, Mohammad Lotfollahi
Main category: cs.LG
TL;DR: DirMoE introduces a novel differentiable routing mechanism for Mixture-of-Experts models using Dirichlet variational autoencoder framework to disentangle expert selection and contribution distribution.
Details
Motivation: Existing MoE routers rely on non-differentiable Top-k+Softmax, which conflates two distinct decisions: which experts to activate and how to distribute contributions among them, limiting performance and scalability.Method: DirMoE uses a Dirichlet variational autoencoder framework with Bernoulli component for expert selection and Dirichlet component for contribution distribution. It employs Gumbel-Sigmoid relaxation for differentiable expert selection and implicit reparameterization for Dirichlet distribution, with variational ELBO training objective including sparsity penalty.
Result: DirMoE matches or exceeds other routing methods while improving expert specialization, with fully differentiable forward pass and precise control over number of active experts.
Conclusion: DirMoE provides an end-to-end differentiable routing mechanism that fundamentally disentangles expert selection and contribution distribution, offering improved performance and expert specialization for MoE models.
Abstract: Mixture-of-Experts (MoE) models have demonstrated exceptional performance in large-scale language models. Existing routers typically rely on non-differentiable Top-$k$+Softmax, limiting their performance and scalability. We argue that two distinct decisions, which experts to activate and how to distribute expert contributions among them, are conflated in standard Top-$k$+Softmax. We introduce Dirichlet-Routed MoE (DirMoE), a novel end-to-end differentiable routing mechanism built on a Dirichlet variational autoencoder framework. This design fundamentally disentangles the core routing problems: expert selection, modeled by a Bernoulli component, and expert contribution among chosen experts, handled by a Dirichlet component. The entire forward pass remains fully differentiable through the use of Gumbel-Sigmoid relaxation for the expert selection and implicit reparameterization for the Dirichlet distribution. Our training objective, a variational ELBO, includes a direct sparsity penalty that precisely controls the number of active experts in expectation, alongside a schedule for key hyperparameters that guides the model from an exploratory to a definitive routing state. Moreover, our DirMoE router matches or exceeds other methods while improving expert specialization.
[972] ShapeCond: Fast Shapelet-Guided Dataset Condensation for Time Series Classification
Sijia Peng, Yun Xiong, Xi Chen, Yi Xie, Guanzhi Li, Yanwei Yu, Yangyong Zhu, Zhiqiang Shen
Main category: cs.LG
TL;DR: ShapeCond is a novel time series dataset condensation framework that uses shapelet-guided optimization to preserve critical local temporal patterns, achieving faster synthesis and better downstream classification accuracy than prior methods.
Details
Motivation: Time series data growth strains storage and computation, but existing dataset condensation methods are image-centric and fail to capture time-series-specific temporal structure, particularly local discriminative motifs like shapelets.Method: ShapeCond uses a shapelet-guided optimization strategy with shapelet-assisted synthesis that is independent of sequence length, explicitly preserving critical local patterns in the condensed dataset.
Result: ShapeCond achieves 29× faster synthesis than prior state-of-the-art CondTSC, up to 10,000× faster than naive shapelet methods on long sequences, and consistently outperforms all prior time series condensation methods in downstream accuracy.
Conclusion: ShapeCond provides an efficient and effective time series dataset condensation framework that leverages shapelet-based knowledge to preserve temporal structure, offering significant speedups and improved classification performance.
Abstract: Time series data supports many domains (e.g., finance and climate science), but its rapid growth strains storage and computation. Dataset condensation can alleviate this by synthesizing a compact training set that preserves key information. Yet most condensation methods are image-centric and often fail on time series because they miss time-series-specific temporal structure, especially local discriminative motifs such as shapelets. In this work, we propose ShapeCond, a novel and efficient condensation framework for time series classification that leverages shapelet-based dataset knowledge via a shapelet-guided optimization strategy. Our shapelet-assisted synthesis cost is independent of sequence length: longer series yield larger speedups in synthesis (e.g., 29$\times$ faster over prior state-of-the-art method CondTSC for time-series condensation, and up to 10,000$\times$ over naively using shapelets on the Sleep dataset with 3,000 timesteps). By explicitly preserving critical local patterns, ShapeCond improves downstream accuracy and consistently outperforms all prior state-of-the-art time series dataset condensation methods across extensive experiments. Code is available at https://github.com/lunaaa95/ShapeCond.
[973] How to Correctly Report LLM-as-a-Judge Evaluations
Chungpa Lee, Thomas Zeng, Jongwon Jeong, Jy-yong Sohn, Kangwook Lee
Main category: cs.LG
TL;DR: A statistical framework for debiasing LLM-based evaluation scores with uncertainty quantification and adaptive calibration
Details
Motivation: LLMs are increasingly used as scalable evaluators of model responses, but their imperfect sensitivity and specificity introduce bias in evaluation scores. Current approaches lack proper statistical foundations for uncertainty quantification and are vulnerable to distribution shifts.Method: Proposes a plug-in framework that constructs confidence intervals accounting for uncertainty from both test and calibration datasets. Uses adaptive strategy to allocate calibration samples for tighter intervals. Characterizes parameter regimes where LLM-based evaluation outperforms human-only evaluation.
Result: The framework provides unbiased evaluation scores with proper uncertainty quantification, remains robust under distribution shifts between test and calibration datasets, and identifies conditions where LLM-based evaluation is more reliable than human-only evaluation.
Conclusion: The proposed statistical framework enables principled use of LLMs as evaluators by correcting bias, providing uncertainty quantification, and maintaining robustness to distribution shifts, making LLM-based evaluation more reliable than naive approaches.
Abstract: Large language models (LLMs) are widely used as scalable evaluators of model responses in lieu of human annotators. However, imperfect sensitivity and specificity of the LLM judges induce bias in naive evaluation scores. We propose a simple plug-in framework that corrects this bias and enables statistically principled uncertainty quantification. Our framework constructs confidence intervals that account for uncertainty from both the test dataset and a human-labeled calibration dataset. Additionally, it uses an adaptive strategy to allocate calibration samples for tighter intervals. Importantly, we characterize parameter regimes defined by the true evaluation score and the LLM judge’s sensitivity and specificity in which our LLM-based evaluation yields more reliable estimates than human-only evaluation. Moreover, we show that our framework remains unbiased under distribution shift between the test and calibration datasets, in contrast to existing approaches.
[974] Towards Active Synthetic Data Generation for Finetuning Language Models
Samuel Kessler, Menglin Xia, Daniel Madrigal Diaz, Dongge Han, Helia Heshemi, Saravan Rajmohan, Victor Ruehle, Jordan T. Ash
Main category: cs.LG
TL;DR: Iterative synthetic data generation using active learning selection improves student model performance over static generation for fixed compute budgets
Details
Motivation: Current synthetic data generation for language model finetuning typically happens before training, but iterative generation guided by the student's current state could be more effective for improving model capabilitiesMethod: Proposes iterative, closed-loop synthetic data generation where teacher model generates samples guided by current student state, using simple active learning selection criteria (like uncertainty sampling) to curate finetuning data
Result: Iterative generation with active learning selection outperforms static generation for fixed compute budgets across four mathematical/logical reasoning datasets using four different small language models
Conclusion: Iterative synthetic data generation with simple active learning criteria is an effective approach for improving student model performance, outperforming more complex LLM-specific methods
Abstract: A common and effective means for improving language model capabilities involves finetuning a student'' language model's parameters on generations from a more proficient teacher’’ model. Termed ``synthetic data’’, these generations are often produced before any student finetuning, but some work has considered generating new synthetic samples as training progresses. This paper studies and advocates for the latter case, where data are generated in an iterative, closed-loop fashion that is guided by the current state of the student model. For a fixed budget of generated samples, or a budget in terms of compute spent querying a teacher, we show that this curation of finetuning data affords improved student performance over static generation. Further, while there have been several LLM-specific methods proposed that operate in this regime, we find that simple, inexpensive selection criteria from the active learning literature tend to be most performant. We validate these claims across four mathematical and logical reasoning datasets using four different small language models.
[975] Dynamic Rank Reinforcement Learning for Adaptive Low-Rank Multi-Head Self Attention in Large Language Models
Caner Erden
Main category: cs.LG
TL;DR: DR-RL is a dynamic rank modulation method for attention mechanisms that uses reinforcement learning to optimize rank selection in real-time, balancing attention fidelity against computational efficiency, achieving 40% FLOPs reduction while maintaining accuracy.
Details
Motivation: Existing low-rank approximations for attention mechanisms rely on static rank assumptions, which lack flexibility across diverse linguistic contexts and cannot adapt to real-time sequence dynamics, layer-specific sensitivities, or hardware constraints.Method: Uses deep reinforcement learning agent to formulate rank selection as sequential policy optimization, integrates lightweight Transformer-based policy network, employs online matrix perturbation bounds for stability, and uses batched SVD operations for scalable deployment.
Result: Reduces FLOPs by over 40% in long-sequence regimes (L > 4096) while maintaining downstream accuracy statistically equivalent to full-rank attention. Achieves 92.78% accuracy on SST-2 sentiment analysis, matching full-rank baselines and outperforming static low-rank methods.
Conclusion: DR-RL provides an effective dynamic rank modulation approach that significantly improves computational efficiency while maintaining model performance, demonstrating real-world applicability beyond standard language modeling benchmarks.
Abstract: Dynamic Rank Reinforcement Learning (DR-RL) approximations rely on static rank assumptions, limiting their flexibility across diverse linguistic contexts. Our method dynamically modulates ranks based on real-time sequence dynamics, layer-specific sensitivities, and hardware constraints. The core innovation is a deep reinforcement learning agent that formulates rank selection as a sequential policy optimization problem, strictly balancing attention fidelity against computational latency. To ensure stability during inference, we derive and employ online matrix perturbation bounds, enabling incremental rank updates without the prohibitive cost of full decomposition. Furthermore, the integration of a lightweight Transformer-based policy network and batched Singular Value Decomposition (SVD) operations ensures scalable deployment on modern architectures. Extensive experiments demonstrate that DR-RL significantly reduces Floating Point Operations (FLOPs) by over 40% in long-sequence regimes (L > 4096) while maintaining downstream accuracy statistically equivalent to full-rank attention. Beyond standard language modeling benchmarks, we validate the real-world applicability of DR-RL on the GLUE benchmark. Specifically, our method achieves 92.78% accuracy on the SST-2 sentiment analysis task, matching the performance of full-rank baselines and outperforming static low-rank methods, such as Performer and Nyströmformer, by a significant margin.
[976] Fast KVzip: Efficient and Accurate LLM Inference with Gated KV Eviction
Jang-Hyun Kim, Dongyoon Han, Sangdoo Yun
Main category: cs.LG
TL;DR: A gating-based KV cache eviction method for LLMs that achieves high compression ratios (up to 70%) with negligible computational cost while maintaining near-lossless performance across various tasks.
Details
Motivation: Existing KV cache compression techniques for LLMs often face a trade-off between performance degradation and computational overhead, creating a need for efficient cache management solutions that maintain performance while reducing memory usage.Method: Proposes lightweight sink-attention gating modules to identify and retain critical KV pairs, with a gate training algorithm that uses forward passes only (no backpropagation) and a task-agnostic reconstruction objective for generalization.
Result: Achieves up to 70% KV cache eviction while maintaining near-lossless performance across Qwen2.5-1M, Qwen3, and Gemma3 families, with consistent results on long-context understanding, code comprehension, and mathematical reasoning tasks.
Conclusion: The gating-based KV cache eviction method provides an efficient solution for LLM deployment with high compression ratios and minimal computational cost, demonstrating strong generalization across diverse tasks.
Abstract: Efficient key-value (KV) cache management is crucial for the practical deployment of large language models (LLMs), yet existing compression techniques often incur a trade-off between performance degradation and computational overhead. We propose a novel gating-based KV cache eviction method for frozen-weight LLMs that achieves high compression ratios with negligible computational cost. Our approach introduces lightweight sink-attention gating modules to identify and retain critical KV pairs, and integrates seamlessly into both the prefill and decoding stages. The proposed gate training algorithm relies on forward passes of an LLM, avoiding expensive backpropagation, while achieving strong task generalization through a task-agnostic reconstruction objective. Extensive experiments across the Qwen2.5-1M, Qwen3, and Gemma3 families show that our method maintains near-lossless performance while evicting up to 70% of the KV cache. The results are consistent across a wide range of tasks, including long-context understanding, code comprehension, and mathematical reasoning, demonstrating the generality of our approach.
[977] EvoMU: Evolutionary Machine Unlearning
Pawel Batorski, Paul Swoboda
Main category: cs.LG
TL;DR: EvoMU uses evolutionary search to automatically discover optimal unlearning loss functions for machine unlearning tasks, achieving state-of-the-art results with limited computational resources.
Details
Motivation: The space of possible unlearning loss functions is vast and finding optimal ones is challenging. Different datasets may require different loss functions, and there's no universal optimal solution. Manual search is inefficient, so automated discovery is needed.Method: Uses evolutionary search procedure to automatically find task-specific unlearning loss functions in the vast space of possible formulations. Employs a small 4B parameter model (Qwen3-4B-Thinking) to achieve results with limited computational resources.
Result: Surpasses previous loss-based unlearning formulations on TOFU-5%, TOFU-10%, MUSE and WMDP benchmarks by synthesizing novel unlearning losses. Achieves state-of-the-art results while demonstrating the potential of AI co-scientists with limited resources.
Conclusion: EvoMU successfully demonstrates automated scientific discovery for machine unlearning, showing that evolutionary search can find dataset-specific loss functions that outperform existing manually-designed ones, even with limited computational budgets.
Abstract: Machine unlearning aims to unlearn specified training data (e.g. sensitive or copyrighted material). A prominent approach is to fine-tune an existing model with an unlearning loss that retains overall utility. The space of suitable unlearning loss functions is vast, making the search for an optimal loss function daunting. Additionally, there might not even exist a universally optimal loss function: differences in the structure and overlap of the forget and retain data can cause a loss to work well in one setting but over-unlearn or under-unlearn in another. Our approach EvoMU tackles these two challenges simultaneously. An evolutionary search procedure automatically finds task-specific losses in the vast space of possible unlearning loss functions. This allows us to find dataset-specific losses that match or outperform existing losses from the literature, without the need for a human-in-the-loop. This work is therefore an instance of automatic scientific discovery, a.k.a. an AI co-scientist. In contrast to previous AI co-scientist works, we do so on a budget: We achieve SotA results using a small 4B parameter model (Qwen3-4B-Thinking), showing the potential of AI co-scientists with limited computational resources. Our experimental evaluation shows that we surpass previous loss-based unlearning formulations on TOFU-5%, TOFU-10%, MUSE and WMDP by synthesizing novel unlearning losses. Our code is available at https://github.com/Batorskq/EvoMU.
[978] Learning While Staying Curious: Entropy-Preserving Supervised Fine-Tuning via Adaptive Self-Distillation for Large Reasoning Models
Hao Wang, Hao Gu, Hongming Piao, Kaixiong Gong, Yuxiao Ye, Xiangyu Yue, Sirui Han, Yike Guo, Dapeng Wu
Main category: cs.LG
TL;DR: CurioSFT: An entropy-preserving supervised fine-tuning method that enhances exploration capabilities through intrinsic curiosity for better downstream reinforcement learning performance in reasoning tasks.
Details
Motivation: Standard SFT-then-RL pipeline limits RL benefits because SFT causes overconfidence and reduces generation diversity, narrowing the solution space for RL exploration. Existing entropy regularization methods flatten distributions uniformly without improving meaningful exploration capability.Method: CurioSFT uses: (1) Self-Exploratory Distillation - distills model toward self-generated, temperature-scaled teacher to encourage exploration within capability; (2) Entropy-Guided Temperature Selection - adaptively adjusts distillation strength to amplify exploration at reasoning tokens while stabilizing factual tokens to mitigate knowledge forgetting.
Result: On mathematical reasoning tasks: CurioSFT outperforms vanilla SFT by 2.5 points on in-distribution tasks and 2.9 points on out-of-distribution tasks. Exploration capabilities preserved during SFT translate to 5.0 point average improvement in RL stage.
Conclusion: CurioSFT effectively preserves exploration capabilities during SFT, leading to better downstream RL performance by maintaining solution space diversity and enabling more effective exploration in reinforcement learning stages.
Abstract: The standard post-training recipe for large reasoning models, supervised fine-tuning followed by reinforcement learning (SFT-then-RL), may limit the benefits of the RL stage: while SFT imitates expert demonstrations, it often causes overconfidence and reduces generation diversity, leaving RL with a narrowed solution space to explore. Adding entropy regularization during SFT is not a cure-all; it tends to flatten token distributions toward uniformity, increasing entropy without improving meaningful exploration capability. In this paper, we propose CurioSFT, an entropy-preserving SFT method designed to enhance exploration capabilities through intrinsic curiosity. It consists of (a) Self-Exploratory Distillation, which distills the model toward a self-generated, temperature-scaled teacher to encourage exploration within its capability; and (b) Entropy-Guided Temperature Selection, which adaptively adjusts distillation strength to mitigate knowledge forgetting by amplifying exploration at reasoning tokens while stabilizing factual tokens. Extensive experiments on mathematical reasoning tasks demonstrate that, in SFT stage, CurioSFT outperforms the vanilla SFT by 2.5 points on in-distribution tasks and 2.9 points on out-of-distribution tasks. We also verify that exploration capabilities preserved during SFT successfully translate into concrete gains in RL stage, yielding an average improvement of 5.0 points.
[979] EBPO: Empirical Bayes Shrinkage for Stabilizing Group-Relative Policy Optimization
Kevin Han, Yuhang Zhou, Mingze Gao, Gedi Zhou, Serena Li, Abhishek Kumar, Xiangjun Fan, Weiwei Li, Lizhu Zhang
Main category: cs.LG
TL;DR: EBPO improves RL for LLMs by using empirical Bayes to stabilize policy optimization with global statistics, addressing variance and gradient issues in existing methods like GRPO.
Details
Motivation: Current RL methods for LLMs (like GRPO) suffer from instability due to high variance with small group sizes and vanishing gradients when all responses get zero rewards, limiting their effectiveness in verifiable reward settings.Method: Empirical Bayes Policy Optimization (EBPO) regularizes local group-based baselines by combining them with global statistics via a shrinkage estimator, using Welford’s online algorithm to update the global prior dynamically.
Result: EBPO outperforms GRPO and other baselines on benchmarks like AIME and OlympiadBench, showing superior training stability, better performance with small group sizes, and benefits from curriculum learning.
Conclusion: EBPO provides a theoretically grounded and empirically effective solution to stability issues in RL for LLMs, enabling more robust reasoning enhancement with verifiable rewards.
Abstract: Reinforcement Learning with Verifiable Rewards (RLVR) has proven effective for enhancing the reasoning capabilities of Large Language Models (LLMs). However, dominant approaches like Group Relative Policy Optimization (GRPO) face critical stability challenges: they suffer from high estimator variance under computational constraints (small group sizes) and vanishing gradient signals in saturated failure regimes where all responses yield identical zero rewards. To address this, we propose Empirical Bayes Policy Optimization (EBPO), a novel framework that regularizes local group-based baselines by borrowing strength from the policy’s accumulated global statistics. Instead of estimating baselines in isolation, EBPO employs a shrinkage estimator that dynamically balances local group statistics with a global prior updated via Welford’s online algorithm. Theoretically, we demonstrate that EBPO guarantees strictly lower Mean Squared Error (MSE), bounded entropy decay, and non-vanishing penalty signals in failure scenarios compared to GRPO. Empirically, EBPO consistently outperforms GRPO and other established baselines across diverse benchmarks, including AIME and OlympiadBench. Notably, EBPO exhibits superior training stability, achieving high-performance gains even with small group sizes, and benefits significantly from difficulty-stratified curriculum learning.
[980] Towards Transparent and Efficient Anomaly Detection in Industrial Processes through ExIFFI
Davide Frizzo, Francesco Borsatti, Alessio Arcudi, Antonio De Moliner, Roberto Oboe, Gian Antonio Susto
Main category: cs.LG
TL;DR: ExIFFI provides fast, efficient explanations for anomaly detection using Extended Isolation Forest, tested on industrial datasets with strong performance metrics.
Details
Motivation: In Industry 5.0, interpretable anomaly detection is needed beyond binary labels to help users understand model decisions and underlying issues in industrial operations.Method: Applies ExIFFI (Explainable Isolation Forest Feature Importance) to Extended Isolation Forest for anomaly detection, tested on three industrial datasets with quantitative evaluation using feature selection proxy task metrics.
Result: ExIFFI achieves over 90% average precision on all benchmarks, outperforms state-of-the-art XAI approaches in explanation effectiveness, computational efficiency, and improves raw anomaly detection performance.
Conclusion: ExIFFI represents the first successful industrial application of explainable anomaly detection, demonstrating practical value for Industry 5.0 with interpretable outcomes.
Abstract: Anomaly Detection (AD) is crucial in industrial settings to streamline operations by detecting underlying issues. Conventional methods merely label observations as normal or anomalous, lacking crucial insights. In Industry 5.0, interpretable outcomes become desirable to enable users to understand the rational under model decisions. This paper presents the first industrial application of ExIFFI, a recent approach for fast, efficient explanations for the Extended Isolation Forest (EIF) AD method. ExIFFI is tested on three industrial datasets, demonstrating superior explanation effectiveness, computational efficiency and improved raw anomaly detection performances. ExIFFI reaches over then 90% of average precision on all the benchmarks considered in the study and overperforms state-of-the-art Explainable Artificial Intelligence (XAI) approaches in terms of the feature selection proxy task metric which was specifically introduced to quantitatively evaluate model explanations.
[981] Why Rectified Power Unit Networks Fail and How to Improve It: An Effective Field Theory Perspective
Taeyoung Kim, Myungjoo Kang
Main category: cs.LG
TL;DR: The paper introduces MRePU, a modified version of the RePU activation function that addresses training stability issues in deep networks while preserving differentiability and approximation properties.
Details
Motivation: Deep RePU networks suffer from vanishing/exploding gradient problems during training, making them unstable regardless of initialization. The authors aim to develop a modified activation function that maintains RePU's advantages while ensuring stable training.Method: Using effective field theory perspective to identify root causes of RePU failures, then proposing Modified Rectified Power Unit (MRePU) activation function that satisfies criticality conditions for stable training, placing it in a distinct universality class.
Result: MRePU shows significant improvements in training stability and performance across polynomial regression, physics-informed neural networks (PINNs), and real-world vision tasks.
Conclusion: MRePU serves as a robust alternative for building deep neural networks, addressing RePU’s limitations while preserving its advantages like differentiability and universal approximation properties.
Abstract: The Rectified Power Unit (RePU) activation function, a differentiable generalization of the Rectified Linear Unit (ReLU), has shown promise in constructing neural networks due to its smoothness properties. However, deep RePU networks often suffer from critical issues such as vanishing or exploding values during training, rendering them unstable regardless of hyperparameter initialization. Leveraging the perspective of effective field theory, we identify the root causes of these failures and propose the Modified Rectified Power Unit (MRePU) activation function. MRePU addresses RePU’s limitations while preserving its advantages, such as differentiability and universal approximation properties. Theoretical analysis demonstrates that MRePU satisfies criticality conditions necessary for stable training, placing it in a distinct universality class. Extensive experiments validate the effectiveness of MRePU, showing significant improvements in training stability and performance across various tasks, including polynomial regression, physics-informed neural networks (PINNs) and real-world vision tasks. Our findings highlight the potential of MRePU as a robust alternative for building deep neural networks.
[982] Disentangled Parameter-Efficient Linear Model for Long-Term Time Series Forecasting
Yuang Zhao, Tianyu Li, Jiadong Chen, Shenrong Ye, Fuxin Jiang, Xiaofeng Gao
Main category: cs.LG
TL;DR: DiPE-Linear is a novel time series forecasting model that disentangles monolithic linear mappings into specialized modules for better efficiency and performance.
Details
Motivation: Linear models for long-term time series forecasting have parameter redundancy and entanglement of temporal/frequential properties, which DiPE-Linear aims to solve through disentangled architecture.Method: Disentangles monolithic weight matrix into three components: Static Frequential Attention, Static Time Attention, and Independent Frequential Mapping, with Low-rank Weight Sharing for multivariate data.
Result: Achieves state-of-the-art performance with significantly fewer parameters, reducing parameter complexity from quadratic to linear and computational complexity to log-linear.
Conclusion: DiPE-Linear establishes a new efficient baseline for long-term time series forecasting with disentangled architecture that improves both performance and efficiency.
Abstract: Long-term Time Series Forecasting (LTSF) is crucial across various domains, but complex deep models like Transformers are often prone to overfitting on extended sequences. Linear Fully Connected models have emerged as a powerful alternative, achieving competitive results with fewer parameters. However, their reliance on a single, monolithic weight matrix leads to quadratic parameter redundancy and an entanglement of temporal and frequential properties. To address this, we propose DiPE-Linear, a novel model that disentangles this monolithic mapping into a sequence of specialized, parameter-efficient modules. DiPE-Linear features three core components: Static Frequential Attention to prioritize critical frequencies, Static Time Attention to focus on key time steps, and Independent Frequential Mapping to independently process frequency components. A Low-rank Weight Sharing policy further enhances efficiency for multivariate data. This disentangled architecture collectively reduces parameter complexity from quadratic to linear and computational complexity to log-linear. Experiments on real-world datasets show that DiPE-Linear delivers state-of-the-art performance with significantly fewer parameters, establishing a new and highly efficient baseline for LTSF. Our code is available at https://github.com/wintertee/DiPE-Linear/
[983] SoK: Blockchain-Based Decentralized AI (DeAI)
Elizabeth Lui, Rui Sun, Vatsal Shah, Xihan Xiong, Jiahao Sun, Davide Crapis, William Knottenbelt, Zhipeng Wang
Main category: cs.LG
TL;DR: First systematic review of blockchain-based Decentralized AI (DeAI) that formalizes the paradigm, provides taxonomy of solutions, analyzes blockchain’s role in secure collaboration, reviews security risks, and identifies future research directions.
Details
Motivation: Centralized AI systems face critical challenges including single points of failure, biases, privacy risks, and scalability limitations. Blockchain-based DeAI offers a promising decentralized alternative, but lacks systematic academic analysis despite rapid industry adoption.Method: Conducts a Systematization of Knowledge (SoK) approach: 1) Provides formal definition of DeAI, 2) Creates taxonomy of existing solutions based on AI lifecycle stages, 3) Analyzes blockchain’s role in enabling secure and incentive-compatible collaboration, 4) Reviews security risks across DeAI lifecycle, 5) Empirically evaluates representative mitigation techniques.
Result: Presents first comprehensive academic framework for DeAI, offering structured understanding of technical foundations, opportunities, and challenges. Identifies blockchain’s key roles in trust, transparency, and coordination for decentralized AI systems.
Conclusion: Blockchain-based DeAI addresses fundamental limitations of centralized AI through decentralization and transparency. The SoK provides foundational framework for future research, highlighting open challenges in security, scalability, and practical implementation of trustworthy decentralized AI systems.
Abstract: Centralization enhances the efficiency of Artificial Intelligence (AI) but also introduces critical challenges, including single points of failure, inherent biases, data privacy risks, and scalability limitations. To address these issues, blockchain-based Decentralized Artificial Intelligence (DeAI) has emerged as a promising paradigm that leverages decentralization and transparency to improve the trustworthiness of AI systems. Despite rapid adoption in industry, the academic community lacks a systematic analysis of DeAI’s technical foundations, opportunities, and challenges. This work presents the first Systematization of Knowledge (SoK) on DeAI, offering a formal definition, a taxonomy of existing solutions based on the AI lifecycle, and an in-depth investigation of the roles of blockchain in enabling secure and incentive-compatible collaboration. We further review security risks across the DeAI lifecycle and empirically evaluate representative mitigation techniques. Finally, we highlight open research challenges and future directions for advancing blockchain-based DeAI.
[984] DeMo: Decoupled Momentum Optimization
Bowen Peng, Lizhang Chen, Baiyu Su, Jeffrey Quesnelle, Diederik P. Kingma, Qiang Liu
Main category: cs.LG
TL;DR: DeMo is a communication-efficient optimization method that decouples momentum updates and uses compression techniques to reduce gradient communication bandwidth by up to 85x while maintaining training convergence.
Details
Motivation: The motivation is to address the severe communication bottleneck in synchronous data-parallel training of large neural networks, where full-precision gradient all-reduce imposes significant bandwidth requirements that limit scalability.Method: DeMo decouples local momentum updates, applies fast orthonormal transforms (like DCT) followed by top-k sparsification, and reuses the momentum buffer as error feedback via momentum subtraction to reduce communication.
Result: Experiments on 300M and 1B-parameter language models show DeMo transmits up to 85x less data per GPU than AdamW-DDP while achieving comparable loss and accuracy, with minimal computational overhead.
Conclusion: DeMo provides a practical solution for communication-efficient distributed training that works across various network topologies including multi-datacenter or Ethernet-based setups.
Abstract: Scaling neural network training increasingly depends on synchronous data-parallelism, yet full-precision gradient all-reduce imposes a severe communication bottleneck. We propose Decoupled Momentum Optimization (DeMo), a drop-in replacement for any momentum-based optimizers that significantly reduces the communication bandwidth while maintaining convergence. DeMo (i) decouples local momentum updates, (ii) applies a fast orthonormal transform (e.g., DCT) followed by top-k sparsification, and (iii) reuses the momentum buffer as error feedback via momentum subtraction. This design reduces per-step communication by up to two orders of magnitude with minimal computational overhead. Experiments on 300M and 1B-parameter DeMo language models show DeMo transmits up to 85x less data per GPU than AdamW-DDP while achieving comparable loss and accuracy. DeMo is topology-agnostic and enables training across multi-datacenter or Ethernet-based setups. Code is available at https://github.com/bloc97/DeMo
[985] Geometric Imbalance in Semi-Supervised Node Classification
Liang Yan, Shengzhong Zhang, Bisheng Li, Menglin Yang, Chen Yang, Min Zhou, Weiyang Ding, Yutong Xie, Zengfeng Huang
Main category: cs.LG
TL;DR: The paper addresses class imbalance in graph data for semi-supervised node classification by introducing the concept of geometric imbalance in Riemannian manifold embedding spaces and proposing a framework to mitigate it.
Details
Motivation: Class imbalance in graph data poses significant challenges for effective node classification, particularly in semi-supervised scenarios where message passing on class-imbalanced graphs leads to geometric ambiguity among minority-class nodes in the embedding space.Method: The authors formally introduce the concept of geometric imbalance, provide theoretical analysis on Riemannian manifolds, and propose a unified framework that mitigates geometric imbalance through pseudo-label alignment, node reordering, and ambiguity filtering techniques.
Result: Extensive experiments on diverse benchmarks show that the proposed approach consistently outperforms existing methods, especially under severe class imbalance conditions.
Conclusion: The work offers new theoretical insights and practical tools for robust semi-supervised node classification by addressing geometric imbalance in graph neural networks.
Abstract: Class imbalance in graph data presents a significant challenge for effective node classification, particularly in semi-supervised scenarios. In this work, we formally introduce the concept of geometric imbalance, which captures how message passing on class-imbalanced graphs leads to geometric ambiguity among minority-class nodes in the riemannian manifold embedding space. We provide a rigorous theoretical analysis of geometric imbalance on the riemannian manifold and propose a unified framework that explicitly mitigates it through pseudo-label alignment, node reordering, and ambiguity filtering. Extensive experiments on diverse benchmarks show that our approach consistently outperforms existing methods, especially under severe class imbalance. Our findings offer new theoretical insights and practical tools for robust semi-supervised node classification.
[986] LEASE: Offline Preference-based Reinforcement Learning with High Sample Efficiency
Xiao-Yin Liu, Guotao Li, Xiao-Hu Zhou, Zeng-Guang Hou
Main category: cs.LG
TL;DR: LEASE: Offline preference-based RL with high sample efficiency using learned transition models to generate unlabeled preference data and uncertainty-aware reward modeling.
Details
Motivation: Offline PbRL faces challenges in acquiring sufficient preference labels due to real-time human feedback requirements. The paper aims to improve sample efficiency in offline preference-based reinforcement learning.Method: Proposes LEASE algorithm that leverages learned transition models to generate unlabeled preference data, uses uncertainty-aware mechanism to select high-confidence/low-variance data for reward modeling, and provides theoretical generalization bounds for reward accuracy.
Result: Experimental results show LEASE achieves comparable performance to baselines with fewer preference data and without online interaction.
Conclusion: LEASE provides an effective approach for sample-efficient offline PbRL with theoretical guarantees and practical performance improvements.
Abstract: Offline preference-based reinforcement learning (PbRL) provides an effective way to overcome the challenges of designing reward and the high costs of online interaction. However, since labeling preference needs real-time human feedback, acquiring sufficient preference labels is challenging. To solve this, this paper proposes a offLine prEference-bAsed RL with high Sample Efficiency (LEASE) algorithm, where a learned transition model is leveraged to generate unlabeled preference data. Considering the pretrained reward model may generate incorrect labels for unlabeled data, we design an uncertainty-aware mechanism to ensure the performance of reward model, where only high confidence and low variance data are selected. Moreover, we provide the generalization bound of reward model to analyze the factors influencing reward accuracy, and demonstrate that the policy learned by LEASE has theoretical improvement guarantee. The developed theory is based on state-action pair, which can be easily combined with other offline algorithms. The experimental results show that LEASE can achieve comparable performance to baseline under fewer preference data without online interaction.
[987] Kernel-based Optimally Weighted Conformal Time-Series Prediction
Jonghyeok Lee, Chen Xu, Yao Xie
Main category: cs.LG
TL;DR: KOWCPI is a novel conformal prediction method for time-series that uses kernel-based optimal weighting to achieve narrower confidence intervals while maintaining coverage guarantees for non-exchangeable data.
Details
Motivation: Traditional conformal prediction methods assume exchangeable data, which doesn't hold for time-series data with temporal dependencies. There's a need for methods that can provide valid coverage guarantees for non-exchangeable time-series data while producing efficient (narrow) prediction intervals.Method: KOWCPI adapts the Reweighted Nadaraya-Watson (RNW) estimator for quantile regression on dependent data and learns optimal data-adaptive weights. It establishes conditional coverage guarantees under strong mixing conditions on non-conformity scores for non-exchangeable time-series data.
Result: KOWCPI demonstrates superior performance on both real and synthetic time-series data compared to state-of-the-art methods, achieving narrower confidence intervals without losing coverage.
Conclusion: KOWCPI provides an effective solution for conformal prediction in time-series settings, addressing the challenge of non-exchangeable data while maintaining coverage guarantees and producing efficient prediction intervals.
Abstract: In this work, we present a novel conformal prediction method for time-series, which we call Kernel-based Optimally Weighted Conformal Prediction Intervals (KOWCPI). Specifically, KOWCPI adapts the classic Reweighted Nadaraya-Watson (RNW) estimator for quantile regression on dependent data and learns optimal data-adaptive weights. Theoretically, we tackle the challenge of establishing a conditional coverage guarantee for non-exchangeable data under strong mixing conditions on the non-conformity scores. We demonstrate the superior performance of KOWCPI on real and synthetic time-series data against state-of-the-art methods, where KOWCPI achieves narrower confidence intervals without losing coverage.
[988] Evaluating Sample Utility for Efficient Data Selection by Mimicking Model Weights
Tzu-Heng Huang, Manjot Bilkhu, John Cooper, Frederic Sala, Javier Movellan
Main category: cs.LG
TL;DR: Mimic Score: geometry-based data quality metric using gradient alignment with pre-trained models, enabling efficient data selection without validation sets
Details
Motivation: Existing data selection methods rely on hand-crafted heuristics, downstream datasets, or expensive computations, limiting scalability and introducing unwanted data dependenciesMethod: Introduces Mimic Score metric measuring alignment between sample gradients and target direction from pre-trained reference model; Grad-Mimic framework with online re-weighting and offline filtering
Result: Improves data efficiency, accelerates convergence, yields consistent gains across six image datasets, enhances CLIP models with 20.7% fewer training steps, enables improved CLIP with 4.7M fewer samples
Conclusion: Mimic Score provides scalable, efficient data selection without validation sets, improving training efficiency and model performance across vision tasks
Abstract: Large-scale web-crawled datasets contain noise, bias, and irrelevant information, necessitating data selection techniques. Existing methods depend on hand-crafted heuristics, downstream datasets, or require expensive influence-based computations – all of which limit scalability and introduce unwanted data dependencies. To address this, we introduce the Mimic Score, a simple and geometry-based data-quality metric that evaluates utility by measuring alignment between a sample’s gradients and a target direction induced by a pre-trained reference model. This leverages readily available model weights, avoids needing validation datasets, and incurs minimal computational overheads. Building on this metric, we propose Grad-Mimic, a two-stage framework that re-weights samples online to accelerate training and aggregates sample utilities offline to construct effective data filters. Empirically, we show that using mimic scores to guide training improves data efficiency, accelerates convergence, yields consistent performance gains across six image datasets, and enhances CLIP models with 20.7% fewer training steps. Additionally, mimic score-based filters augment existing filtering techniques, enabling improved CLIP models trained with 4.7 million fewer samples.
[989] Provable Domain Adaptation for Offline Reinforcement Learning with Limited Samples
Weiqin Chen, Xinjie Zhang, Sandipan Mishra, Santiago Paternain
Main category: cs.LG
TL;DR: First theoretical framework analyzing dataset weighting for offline RL with auxiliary source data, establishing performance bounds and optimal weight computation.
Details
Motivation: Offline RL performance degrades with limited target dataset samples; leveraging auxiliary source datasets (like simulators) can help, but optimal weighting between limited target data and biased source data lacks theoretical understanding.Method: Proposes theoretical framework analyzing impact of dataset weights on offline RL performance, establishes performance bounds, proves existence of optimal weight (computable in closed form under assumptions), provides algorithmic convergence guarantees.
Result: Theoretical results show performance depends on source dataset quality and target dataset size; empirical validation on Procgen and MuJoCo benchmarks substantiates theoretical contributions.
Conclusion: First theoretical exploration of dataset weighting for offline RL with auxiliary data, providing foundations for principled use of source datasets to augment limited target data.
Abstract: Offline reinforcement learning (RL) learns effective policies from a static target dataset. The performance of state-of-the-art offline RL algorithms notwithstanding, it relies on the size of the target dataset, and it degrades if limited samples in the target dataset are available, which is often the case in real-world applications. To address this issue, domain adaptation that leverages auxiliary samples from related source datasets (such as simulators) can be beneficial. However, establishing the optimal way to trade off the limited target dataset and the large-but-biased source dataset while ensuring provably theoretical guarantees remains an open challenge. To the best of our knowledge, this paper proposes the first framework that theoretically explores the impact of the weights assigned to each dataset on the performance of offline RL. In particular, we establish performance bounds and the existence of the optimal weight, which can be computed in closed form under simplifying assumptions. We also provide algorithmic guarantees in terms of convergence to a neighborhood of the optimum. Notably, these results depend on the quality of the source dataset and the number of samples in the target dataset. Our empirical results on the well-known Procgen and MuJoCo benchmarks substantiate the theoretical contributions in this work.
[990] Disentangled Representation Learning for Parametric Partial Differential Equations
Ning Liu, Lu Zhang, Tian Gao, Yue Yu
Main category: cs.LG
TL;DR: DisentangO is a hyper-neural operator architecture that learns disentangled representations from neural operator parameters to extract interpretable physical factors from PDE-governed systems, solving inverse problems while maintaining predictive performance.
Details
Motivation: Neural operators are effective as black-box PDE solvers but lack interpretability of underlying physical mechanisms. The paper aims to bridge this gap by extracting interpretable physical parameters from neural operator representations.Method: Proposes DisentangO: a multi-task neural operator architecture with task-wise adaptive layers that distill varying PDE parameters, combined with a variational autoencoder to disentangle these variations into identifiable latent factors.
Result: Empirical evaluations across supervised, semi-supervised, and unsupervised learning contexts show DisentangO effectively extracts meaningful and interpretable latent features while maintaining predictive performance.
Conclusion: DisentangO successfully bridges the gap between predictive performance and physical understanding in neural operator frameworks by learning disentangled representations that enhance interpretability and generalization.
Abstract: Neural operators (NOs) excel at learning mappings between function spaces, serving as efficient forward solution approximators for PDE-governed systems. However, as black-box solvers, they offer limited insight into the underlying physical mechanism, due to the lack of interpretable representations of the physical parameters that drive the system. To tackle this challenge, we propose a new paradigm for learning disentangled representations from NO parameters, thereby effectively solving an inverse problem. Specifically, we introduce DisentangO, a novel hyper-neural operator architecture designed to unveil and disentangle latent physical factors of variation embedded within the black-box neural operator parameters. At the core of DisentangO is a multi-task NO architecture that distills the varying parameters of the governing PDE through a task-wise adaptive layer, alongside a variational autoencoder that disentangles these variations into identifiable latent factors. By learning these disentangled representations, DisentangO not only enhances physical interpretability but also enables more robust generalization across diverse systems. Empirical evaluations across supervised, semi-supervised, and unsupervised learning contexts show that DisentangO effectively extracts meaningful and interpretable latent features, bridging the gap between predictive performance and physical understanding in neural operator frameworks.
[991] Understanding Large Language Models in Your Pockets: Performance Study on COTS Mobile Devices
Jie Xiao, Qianyi Huang, Xu Chen, Chen Tian
Main category: cs.LG
TL;DR: A comprehensive measurement study of lightweight LLMs (like Gemini Nano, LLAMA2 7B) running locally on commercial smartphones, evaluating both user experience metrics and developer-focused implementation factors across different mobile SoCs.
Details
Motivation: Growing privacy concerns are pushing LLMs toward local deployment on mobile devices. The paper aims to understand the current landscape of LLM deployment on mobile platforms, as lightweight LLMs can now run locally on smartphones, giving users more control over personal data.Method: Conducted a comprehensive measurement study on commercial-off-the-shelf mobile devices, evaluating both user-centric metrics (token throughput, latency, response quality) and developer-critical factors (resource utilization, OS strategies, battery consumption, launch time). Also compared performance across mobile SoCs from major vendors.
Result: Provides insights into performance differences across mobile SoCs in handling LLM workloads, helping developers identify and address bottlenecks. The study reveals how different mobile hardware handles LLM inference and the trade-offs involved in on-device deployment.
Conclusion: The measurement study provides valuable insights for both the development of on-device LLMs and the design of future mobile system architecture, helping bridge the gap between user experience concerns and developer implementation challenges.
Abstract: As large language models (LLMs) increasingly integrate into every aspect of our work and daily lives, there are growing concerns about user privacy, which push the trend toward local deployment of these models. There are a number of lightweight LLMs (e.g., Gemini Nano, LLAMA2 7B) that can run locally on smartphones, providing users with greater control over their personal data. As a rapidly emerging application, we are concerned about their performance on commercial-off-the-shelf mobile devices. To fully understand the current landscape of LLM deployment on mobile platforms, we conduct a comprehensive measurement study on mobile devices. While user experience is the primary concern for end-users, developers focus more on the underlying implementations. Therefore, we evaluate both user-centric metrics-such as token throughput, latency, and response quality-and developer-critical factors, including resource utilization, OS strategies, battery consumption, and launch time. We also provide comprehensive comparisons across the mobile system-on-chips (SoCs) from major vendors, highlighting their performance differences in handling LLM workloads, which may help developers identify and address bottlenecks for mobile LLM applications. We hope that this study can provide insights for both the development of on-device LLMs and the design for future mobile system architecture.
[992] Shallow Diffuse: Robust and Invisible Watermarking through Low-Dimensional Subspaces in Diffusion Models
Wenda Li, Huijie Zhang, Qing Qu
Main category: cs.LG
TL;DR: Shallow Diffuse is a novel watermarking technique for diffusion models that embeds robust, invisible watermarks by leveraging low-dimensional subspaces in image generation, decoupling watermarking from the diffusion process for better consistency and detectability.
Details
Motivation: The widespread use of AI-generated content from diffusion models has raised concerns about misinformation and copyright infringement, creating a need for effective watermarking techniques to identify AI-generated images and prevent misuse.Method: Shallow Diffuse decouples watermarking from the diffusion sampling process by leveraging the existence of a low-dimensional subspace in image generation. It ensures that a substantial portion of the watermark lies in the null space of this subspace, effectively separating watermark embedding from the image generation process.
Result: Theoretical and empirical analyses show that the decoupling strategy greatly enhances consistency of data generation and watermark detectability. Extensive experiments validate that Shallow Diffuse outperforms existing watermarking methods in terms of robustness and consistency.
Conclusion: Shallow Diffuse provides an effective watermarking solution for diffusion models that balances watermark robustness with image generation quality, addressing important concerns about AI-generated content authentication and copyright protection.
Abstract: The widespread use of AI-generated content from diffusion models has raised significant concerns regarding misinformation and copyright infringement. Watermarking is a crucial technique for identifying these AI-generated images and preventing their misuse. In this paper, we introduce Shallow Diffuse, a new watermarking technique that embeds robust and invisible watermarks into diffusion model outputs. Unlike existing approaches that integrate watermarking throughout the entire diffusion sampling process, Shallow Diffuse decouples these steps by leveraging the presence of a low-dimensional subspace in the image generation process. This method ensures that a substantial portion of the watermark lies in the null space of this subspace, effectively separating it from the image generation process. Our theoretical and empirical analyses show that this decoupling strategy greatly enhances the consistency of data generation and the detectability of the watermark. Extensive experiments further validate that our Shallow Diffuse outperforms existing watermarking methods in terms of robustness and consistency. The codes are released at https://github.com/liwd190019/Shallow-Diffuse.
[993] Right Reward Right Time for Federated Learning
Thanh Linh Nguyen, Dinh Thai Hoang, Diep N. Nguyen, Quoc-Viet Pham
Main category: cs.LG
TL;DR: R3T is a time-aware contract-theoretic incentive framework for federated learning that prioritizes critical learning periods to attract high-quality client contributions through optimal reward timing.
Details
Motivation: Existing FL incentive mechanisms treat all training rounds equally, failing to prioritize critical learning periods where low-quality contributions can permanently impair model performance, compounded by information asymmetry due to privacy constraints.Method: Proposes R3T framework with time-aware contract design that formulates cloud utility function balancing model performance and rewards, accounting for client heterogeneity in capabilities, effort, and joining time. Derives optimal contract satisfying individual rationality, incentive compatibility, and budget feasibility constraints.
Result: Simulations show R3T mitigates information asymmetry, increases cloud utility, achieves superior economic efficiency, reduces total clients needed by up to 47.6%, improves convergence time by up to 300% while maintaining competitive test accuracy.
Conclusion: Time-aware incentive mechanisms that prioritize critical learning periods can significantly improve federated learning efficiency by attracting high-quality contributions when they matter most, overcoming information asymmetry challenges.
Abstract: Critical learning periods (CLPs) in federated learning (FL) refer to early stages during which low-quality contributions (e.g., sparse training data availability) can permanently impair the performance of the global model owned by the model owner (i.e., a cloud server). However, existing incentive mechanisms exhibit temporal homogeneity, treating all training rounds as equally important, thereby failing to prioritize and attract high-quality contributions during CLPs. This inefficiency is compounded by information asymmetry due to privacy regulations, where the cloud lacks knowledge of client training capabilities, leading to adverse selection. Thus, in this article, we propose a time-aware contract-theoretic incentive framework, named Right Reward Right Time (R3T), to encourage client involvement, especially during CLPs, to maximize the utility of the cloud server. We formulate a cloud utility function that captures the trade-off between the achieved model performance and rewards allocated for clients’ contributions, explicitly accounting for client heterogeneity in time and system capabilities, effort, and joining time. Then, we devise a CLP-aware incentive mechanism deriving an optimal contract design that satisfies individual rationality, incentive compatibility, and budget feasibility constraints, motivating rational clients to participate early and contribute efforts. By providing the right reward at the right time, our approach can attract the highest-quality contributions during CLPs. Simulation and proof-of-concept studies show that R3T mitigates information asymmetry, increases cloud utility, and yields superior economic efficiency compared to conventional incentive mechanisms. Our proof-of-concept results demonstrate up to a 47.6% reduction in the total number of clients and up to a 300% improvement in convergence time while achieving competitive test accuracy.
[994] Federated Learning Clients Clustering with Adaptation to Data Drifts
Minghao Li, Dmitrii Avdiukhin, Rana Shahout, Nikita Ivkin, Vladimir Braverman, Minlan Yu
Main category: cs.LG
TL;DR: FIELDING is a clustered federated learning framework that handles diverse types of data drift by detecting drift at individual clients and performing selective re-clustering to maintain cluster quality and model performance.
Details
Motivation: Federated learning faces challenges with client heterogeneity slowing convergence and limiting accuracy. Clustered FL helps but client data evolves over time (data drift), breaking cluster homogeneity and degrading performance. Different types of data drift (output values, input features, or their relationships) require adaptive solutions.Method: FIELDING detects drift at individual clients and performs selective re-clustering to balance cluster quality and model performance. It remains robust to malicious clients and varying heterogeneity levels while maintaining low overhead.
Result: FIELDING improves final model accuracy by 1.9-5.9% and achieves target accuracy 1.16x-2.23x faster than existing state-of-the-art CFL methods.
Conclusion: FIELDING effectively handles diverse data drift types in federated learning, improving both accuracy and convergence speed while maintaining robustness and low overhead.
Abstract: Federated Learning (FL) trains deep models across edge devices without centralizing raw data, preserving user privacy. However, client heterogeneity slows down convergence and limits global model accuracy. Clustered FL (CFL) mitigates this by grouping clients with similar representations and training a separate model for each cluster. In practice, client data evolves over time, a phenomenon we refer to as data drift, which breaks cluster homogeneity and degrades performance. Data drift can take different forms depending on whether changes occur in the output values, the input features, or the relationship between them. We propose FIELDING, a CFL framework for handling diverse types of data drift with low overhead. FIELDING detects drift at individual clients and performs selective re-clustering to balance cluster quality and model performance, while remaining robust to malicious clients and varying levels of heterogeneity. Experiments show that FIELDING improves final model accuracy by 1.9-5.9% and achieves target accuracy 1.16x-2.23x faster than existing state-of-the-art CFL methods.
[995] Toward Efficient Exploration by Large Language Model Agents
Dilip Arumugam, Thomas L. Griffiths
Main category: cs.LG
TL;DR: LLM-based RL agents struggle with exploration efficiency; this work implements Posterior Sampling for RL using LLMs to achieve better data-efficient exploration in natural language tasks.
Details
Motivation: Current LLM-based RL agents lack data-efficient exploration capabilities, which is crucial for real-world applications. Classic RL algorithms with proven exploration efficiency are difficult to implement in natural language settings.Method: Instead of fine-tuning or in-context learning to make LLMs implicitly imitate RL algorithms, the authors explicitly implement Posterior Sampling for Reinforcement Learning (PSRL) using LLMs, leveraging its well-studied exploration properties.
Result: The LLM-based implementation of PSRL demonstrates considerably more effective performance in natural language tasks requiring prudent exploration compared to existing LLM agent designs.
Conclusion: LLMs can be effectively used to implement classic, data-efficient RL algorithms like PSRL to address exploration challenges in natural language decision-making tasks.
Abstract: A burgeoning area within reinforcement learning (RL) is the design of sequential decision-making agents centered around large language models (LLMs). While autonomous decision-making agents powered by modern LLMs could facilitate numerous real-world applications, such successes demand agents that are capable of data-efficient RL. One key obstacle to achieving data efficiency in RL is exploration, a challenge that we demonstrate many recent proposals for LLM agent designs struggle to contend with. Meanwhile, classic algorithms from the RL literature known to gracefully address exploration require technical machinery that can be challenging to operationalize in purely natural language settings. In this work, rather than relying on finetuning or in-context learning to coax LLMs into implicitly imitating a RL algorithm, we illustrate how LLMs can be used to explicitly implement an existing RL algorithm (Posterior Sampling for Reinforcement Learning) whose capacity for statistically-efficient exploration is already well-studied. We offer empirical results demonstrating how our LLM-based implementation of a known, data-efficient RL algorithm can be considerably more effective in natural language tasks that demand prudent exploration.
[996] Interpretable Generalized Additive Models for Datasets with Missing Values
Hayden McTavish, Jon Donnelly, Margo Seltzer, Cynthia Rudin
Main category: cs.LG
TL;DR: M-GAM: A sparse generalized additive model approach that handles missing data by incorporating missingness indicators with l0 regularization, maintaining interpretability while improving sparsity over imputation methods.
Details
Motivation: Missing data in datasets poses challenges for maintaining interpretability in machine learning models. Imputation methods complicate feature-to-label mappings, while naive inclusion of missingness indicators sacrifices model sparsity by introducing many additional terms.Method: M-GAM uses a sparse generalized additive modeling approach that incorporates missingness indicators and their interaction terms while maintaining sparsity through l0 regularization, allowing selective inclusion of only relevant missingness terms.
Result: M-GAM provides similar or superior accuracy to prior methods while significantly improving sparsity relative to either imputation or naive inclusion of indicator variables.
Conclusion: M-GAM offers an effective solution for maintaining interpretable models with missing data by balancing accuracy and sparsity through selective inclusion of missingness indicators.
Abstract: Many important datasets contain samples that are missing one or more feature values. Maintaining the interpretability of machine learning models in the presence of such missing data is challenging. Singly or multiply imputing missing values complicates the model’s mapping from features to labels. On the other hand, reasoning on indicator variables that represent missingness introduces a potentially large number of additional terms, sacrificing sparsity. We solve these problems with M-GAM, a sparse, generalized, additive modeling approach that incorporates missingness indicators and their interaction terms while maintaining sparsity through l0 regularization. We show that M-GAM provides similar or superior accuracy to prior methods while significantly improving sparsity relative to either imputation or naive inclusion of indicator variables.
[997] Reducing Aleatoric and Epistemic Uncertainty through Multi-modal Data Acquisition
Arthur Hoarau, Benjamin Quost, Sébastien Destercke, Willem Waegeman
Main category: cs.LG
TL;DR: A framework for uncertainty disentanglement in multimodal AI systems that guides data acquisition decisions across modalities and sample sizes
Details
Motivation: Modern AI systems need to combine data from multiple modalities (text, images, audio, etc.) for accurate predictions, but multimodal data introduces new challenges for uncertainty disentanglement. The traditional assumption that epistemic uncertainty decreases with more data while aleatoric uncertainty is irreducible is challenged in multimodal contexts.Method: Proposes an innovative data acquisition framework where uncertainty disentanglement leads to actionable decisions, allowing sampling in two directions: sample size and data modality. The main hypothesis is that aleatoric uncertainty decreases as the number of modalities increases, while epistemic uncertainty decreases by collecting more observations. Provides proof-of-concept implementations on two multimodal datasets combining ideas from active learning, active feature acquisition, and uncertainty quantification.
Result: The paper presents a framework that enables systematic decision-making about whether to collect more data samples or acquire additional modalities based on uncertainty analysis. Proof-of-concept implementations demonstrate the approach on multimodal datasets.
Conclusion: The proposed framework addresses the unique challenges of uncertainty disentanglement in multimodal AI systems and provides actionable guidance for data acquisition strategies that consider both sample size and modality expansion.
Abstract: To generate accurate and reliable predictions, modern AI systems need to combine data from multiple modalities, such as text, images, audio, spreadsheets, and time series. Multi-modal data introduces new opportunities and challenges for disentangling uncertainty: it is commonly assumed in the machine learning community that epistemic uncertainty can be reduced by collecting more data, while aleatoric uncertainty is irreducible. However, this assumption is challenged in modern AI systems when information is obtained from different modalities. This paper introduces an innovative data acquisition framework where uncertainty disentanglement leads to actionable decisions, allowing sampling in two directions: sample size and data modality. The main hypothesis is that aleatoric uncertainty decreases as the number of modalities increases, while epistemic uncertainty decreases by collecting more observations. We provide proof-of-concept implementations on two multi-modal datasets to showcase our data acquisition framework, which combines ideas from active learning, active feature acquisition and uncertainty quantification.
[998] PiFlow: Principle-Aware Scientific Discovery with Multi-Agent Collaboration
Yingming Pu, Tao Lin, Hongyu Chen
Main category: cs.LG
TL;DR: PiFlow is an information-theoretical framework for LLM-based multi-agent systems that treats automated scientific discovery as structured uncertainty reduction guided by principles like scientific laws, improving efficiency and quality.
Details
Motivation: Existing LLM-based multi-agent systems for scientific discovery often use predefined workflows lacking rationality constraints, leading to aimless hypothesizing and failure to link hypotheses with evidence, hindering systematic uncertainty reduction.Method: PiFlow introduces an information-theoretical framework that treats automated scientific discovery as a structured uncertainty reduction problem guided by principles (e.g., scientific laws), serving as a Plug-and-Play module that generalizes on existing agent architectures.
Result: PiFlow improves discovery efficiency by 31.18%~41.73% and solution quality by 12.47%~31.72% against state-of-the-art methods, delivers 5.6x speedup in time-to-solution while reducing token consumption by up to 27% compared to vanilla agents.
Conclusion: PiFlow establishes a novel paradigm shift in highly efficient agentic scientific discovery, paving the way for more robust and accelerated AI-driven research.
Abstract: Large Language Model (LLM)-based multi-agent systems (MAS) demonstrate remarkable potential for scientific discovery. Existing approaches, however, often automate scientific discovery using predefined workflows that lack rationality constraints. This often leads to aimless hypothesizing and a failure to consistently link hypotheses with evidence, thereby hindering the systematic reduction of uncertainty. Overcoming these limitations fundamentally requires a principled approach to exploration. We introduce PiFlow, an information-theoretical framework, treating automated scientific discovery as a structured uncertainty reduction problem guided by principles (e.g., scientific laws). Extensive evaluations across three distinct scientific domains demonstrate that PiFlow (I) improves discovery efficiency by 31.18%~41.73% and solution quality by 12.47%~31.72% against state-of-the-art methods, (II) delivers a 5.6x speedup in time-to-solution while reducing token consumption by up to 27% compared to vanilla agents, and (III) serves as a Plug-and-Play module that generalizes on existing agent architecture. Overall, PiFlow establishes a novel paradigm shift in highly efficient agentic scientific discovery, paving the way for more robust and accelerated AI-driven research.
[999] CoHiRF: Hierarchical Consensus for Interpretable Clustering Beyond Scalability Limits
Katia Meziani, Bruno Belucci, Karim Lounici, Vladimir R. Kostic
Main category: cs.LG
TL;DR: CoHiRF is a hierarchical consensus meta-algorithm that enables existing clustering methods to scale beyond their computational limits by operating on label assignments, using multiple low-dimensional views, enforcing consensus, and progressively contracting the problem size.
Details
Motivation: Existing clustering methods face computational and memory limitations when dealing with large-scale or high-dimensional data. There's a need to extend the applicability of established clustering algorithms without modifying their core behavior or assumptions.Method: CoHiRF is a meta-algorithm that: 1) applies base clustering methods to multiple low-dimensional feature views or stochastic realizations, 2) enforces agreement through consensus on label assignments, 3) progressively reduces problem size via representative-based contraction, and 4) produces a Cluster Fusion Hierarchy for multi-resolution analysis.
Result: CoHiRF improves robustness to high-dimensional noise, enhances stability under stochastic variability, and enables scalability to regimes where base methods alone are infeasible. It works across centroid-based, kernel-based, density-based, and graph-based clustering methods.
Conclusion: Hierarchical consensus is a practical and flexible tool for large-scale clustering that extends the applicability of existing methods without altering their underlying behavior, providing both scalability and interpretable multi-resolution clustering structures.
Abstract: We introduce CoHiRF (Consensus Hierarchical Random Features), a hierarchical consensus framework that enables existing clustering methods to operate beyond their usual computational and memory limits. CoHiRF is a meta-algorithm that operates exclusively on the label assignments produced by a base clustering method, without modifying its objective function, optimization procedure, or geometric assumptions. It repeatedly applies the base method to multiple low-dimensional feature views or stochastic realizations, enforces agreement through consensus, and progressively reduces the problem size via representative-based contraction. Across a diverse set of synthetic and real-world experiments involving centroid-based, kernel-based, density-based, and graph-based methods, we show that CoHiRF can improve robustness to high-dimensional noise, enhance stability under stochastic variability, and enable scalability to regimes where the base method alone is infeasible. We also provide an empirical characterization of when hierarchical consensus is beneficial, highlighting the role of reproducible label relations and their compatibility with representative-based contraction. Beyond flat partitions, CoHiRF produces an explicit Cluster Fusion Hierarchy, offering a multi-resolution and interpretable view of the clustering structure. Together, these results position hierarchical consensus as a practical and flexible tool for large-scale clustering, extending the applicability of existing methods without altering their underlying behavior.
[1000] Efficient Policy Optimization in Robust Constrained MDPs with Iteration Complexity Guarantees
Sourav Ganguly, Kishan Panaganti, Arnob Ghosh, Adam Wierman
Main category: cs.LG
TL;DR: Novel algorithm for robust constrained MDPs that handles model mismatch between real world and simulator, achieving ε-optimal feasible policies in O(ε⁻²) iterations without binary search.
Details
Motivation: Real-world control systems require safe policies under constraints, but simulators often fail to capture real-world adversities. Need to learn policies that maximize reward while satisfying constraints even when there's mismatch between real model and accessible simulator/nominal model.Method: Proposes a novel technique for robust constrained MDP (RCMDP) that minimizes constraint value function to satisfy constraints, then maximizes robust reward value function when constraints are satisfied. Avoids issues with primal-dual methods (lack of strong duality) and standard robust value-iteration (different worst-case models for reward vs constraint).
Result: Algorithm finds policy with at most ε sub-optimality and feasible policy after O(ε⁻²) iterations. Reduces computation time by at least 4x for smaller discount factors and 6x for larger discount factors compared to state-of-the-art methods by eliminating binary search.
Conclusion: The proposed method efficiently solves robust constrained MDP problems with model mismatch, providing practical algorithm for safe policy learning in real-world control systems with uncertain environments.
Abstract: Constrained decision-making is essential for designing safe policies in real-world control systems, yet simulated environments often fail to capture real-world adversities. We consider the problem of learning a policy that will maximize the cumulative reward while satisfying a constraint, even when there is a mismatch between the real model and an accessible simulator/nominal model. In particular, we consider the robust constrained Markov decision problem (RCMDP) where an agent needs to maximize the reward and satisfy the constraint against the worst possible stochastic model under the uncertainty set centered around an unknown nominal model. Primal-dual methods, effective for standard constrained MDP (CMDP), are not applicable here because of the lack of the strong duality property. Further, one cannot apply the standard robust value-iteration based approach on the composite value function either as the worst case models may be different for the reward value function and the constraint value function. We propose a novel technique that effectively minimizes the constraint value function–to satisfy the constraints; on the other hand, when all the constraints are satisfied, it can simply maximize the robust reward value function. We prove that such an algorithm finds a policy with at most $ε$ sub-optimality and feasible policy after $O(ε^{-2})$ iterations. In contrast to the state-of-the-art method, we do not need to employ a binary search, thus, we reduce the computation time by at least 4x for smaller value of discount factor ($γ$) and by at least 6x for larger value of $γ$.
[1001] From Features to Transformers: Redefining Ranking for Scalable Impact
Fedor Borisyuk, Lars Hertel, Ganesh Parameswaran, Gaurav Srivastava, Sudarshan Srinivasa Ramanujam, Borja Ocejo, Peng Du, Andrei Akterskii, Neil Daftary, Shao Tang, Daqi Sun, Qiang Charles Xiao, Deepesh Nathani, Mohit Kothari, Yun Dai, Guoyao Li, Aman Gupta
Main category: cs.LG
TL;DR: LiGR is LinkedIn’s large-scale transformer-based ranking framework that replaces manual feature engineering with learned representations, validates scaling laws for ranking, and enables set-wise scoring for improved diversity.
Details
Motivation: To bring state-of-the-art transformer architectures into production for ranking systems at LinkedIn, reducing reliance on manual feature engineering while improving performance through learned representations and scaling.Method: Modified transformer architecture with learned normalization and simultaneous set-wise attention to user history and ranked items, enabling single-pass processing and efficient serving of large models.
Result: Achieved: (1) outperformed previous state-of-the-art using only few features vs hundreds, (2) validated scaling laws showing improved performance with larger models/data/context, (3) automated diversity improvements through set-wise scoring.
Conclusion: LiGR successfully brings transformer-based modeling to production ranking systems, demonstrating the effectiveness of learned representations over manual feature engineering and the benefits of scaling for ranking tasks.
Abstract: We present LiGR, a large-scale ranking framework developed at LinkedIn that brings state-of-the-art transformer-based modeling architectures into production. We introduce a modified transformer architecture that incorporates learned normalization and simultaneous set-wise attention to user history and ranked items. This architecture enables several breakthrough achievements, including: (1) the deprecation of most manually designed feature engineering, outperforming the prior state-of-the-art system using only few features (compared to hundreds in the baseline), (2) validation of the scaling law for ranking systems, showing improved performance with larger models, more training data, and longer context sequences, and (3) simultaneous joint scoring of items in a set-wise manner, leading to automated improvements in diversity. To enable efficient serving of large ranking models, we describe techniques to scale inference effectively using single-pass processing of user history and set-wise attention. We also summarize key insights from various ablation studies and A/B tests, highlighting the most impactful technical approaches.
[1002] Who Gets Credit or Blame? Attributing Accountability in Modern AI Systems
Shichang Zhang, Hongzhe Du, Jiaqi W. Ma, Himabindu Lakkaraju
Main category: cs.LG
TL;DR: A framework for attributing AI model behavior to specific development stages (pretraining, fine-tuning, alignment) using counterfactual analysis without retraining.
Details
Motivation: Modern AI systems are developed through multiple stages, raising accountability questions about which stage is responsible for model successes or failures.Method: Proposes a general framework with estimators that answer counterfactual questions about stage effects, accounting for data and optimization dynamics (learning rate, momentum, weight decay) without retraining.
Result: Successfully quantifies stage accountability, identifies and removes spurious correlations in image classification and text toxicity detection tasks developed across multiple stages.
Conclusion: Provides a practical tool for model analysis and represents a significant step toward more accountable AI development.
Abstract: Modern AI systems are typically developed through multiple stages-pretraining, fine-tuning rounds, and subsequent adaptation or alignment, where each stage builds on the previous ones and updates the model in distinct ways. This raises a critical question of accountability: when a deployed model succeeds or fails, which stage is responsible, and to what extent? We pose the accountability attribution problem for tracing model behavior back to specific stages of the model development process. To address this challenge, we propose a general framework that answers counterfactual questions about stage effects: how would the model’s behavior have changed if the updates from a particular stage had not occurred? Within this framework, we introduce estimators that efficiently quantify stage effects without retraining the model, accounting for both the data and key aspects of model optimization dynamics, including learning rate schedules, momentum, and weight decay. We demonstrate that our approach successfully quantifies the accountability of each stage to the model’s behavior. Based on the attribution results, our method can identify and remove spurious correlations learned during image classification and text toxicity detection tasks that were developed across multiple stages. Our approach provides a practical tool for model analysis and represents a significant step toward more accountable AI development.
[1003] Deep Meta Coordination Graphs for Multi-agent Reinforcement Learning
Nikunj Gupta, James Zachary Hare, Rajgopal Kannan, Viktor Prasanna
Main category: cs.LG
TL;DR: DMCG learns dynamic meta coordination graphs for multi-agent reinforcement learning, using graph neural networks to represent evolving agent interactions and improve coordination.
Details
Motivation: Traditional coordination graphs in MARL often use fixed structures that may not capture complex, dynamic agent interactions needed for effective cooperation in challenging tasks.Method: DMCG dynamically composes meta coordination graphs that evolve during learning, using graph convolutional networks to integrate agent information and jointly optimize graphs with value functions for end-to-end learning.
Result: DMCG achieves state-of-the-art coordination performance and sample efficiency on challenging cooperative tasks, outperforming both graph-based and non-graph-based MARL baselines.
Conclusion: Dynamic meta coordination graphs enable more expressive representation of agent interactions and facilitate effective coordination in cooperative MARL through end-to-end learning of interaction representations and policies.
Abstract: This paper presents deep meta coordination graphs (DMCG) for learning cooperative policies in multi-agent reinforcement learning (MARL). Coordination graph formulations encode local interactions and accordingly factorize the joint value function of all agents to improve efficiency in MARL. Through DMCG, we dynamically compose what we refer to as \textit{meta coordination graphs}, to learn a more expressive representation of agent interactions and use them to integrate agent information through graph convolutional networks. The goal is to enable an evolving coordination graph to guide effective coordination in cooperative MARL tasks. The graphs are jointly optimized with agents’ value functions to learn to implicitly reason about joint actions, facilitating the end-to-end learning of interaction representations and coordinated policies. We demonstrate that DMCG consistently achieves state-of-the-art coordination performance and sample efficiency on challenging cooperative tasks, outperforming several prior graph-based and non-graph-based MARL baselines. Through several ablations, we also isolate the impact of individual components in DMCG, showing that the observed improvements are due to the meaningful design choices in this approach. We also include an analysis of its computational complexity to discuss its practicality in real-world applications. All codes can be found here: {\color{blue}{https://github.com/Nikunj-Gupta/dmcg-marl}.
[1004] AlphaSteer: Learning Refusal Steering with Principled Null-Space Constraint
Leheng Sheng, Changshuo Shen, Weixiang Zhao, Junfeng Fang, Xiaohao Liu, Zhenkai Liang, Xiang Wang, An Zhang, Tat-Seng Chua
Main category: cs.LG
TL;DR: AlphaSteer is a theoretically grounded activation steering method that enhances LLM safety against jailbreak attacks while preserving utility on benign prompts through learnable steering vectors.
Details
Motivation: Current activation steering methods for LLM safety face a fundamental trade-off between safety and utility - indiscriminate steering vectors cause over-refusal on benign prompts, degrading performance. Existing solutions lack theoretical grounding, limiting their robustness and effectiveness.Method: AlphaSteer treats activation steering as a learnable process with two principled objectives: 1) utility preservation via learning to construct nearly zero vectors for benign data using null-space constraints, and 2) safety enhancement via learning refusal direction vectors for malicious data using linear regression.
Result: Experiments across multiple jailbreak attacks and utility benchmarks demonstrate AlphaSteer significantly improves LLM safety without compromising general capabilities, outperforming prior methods.
Conclusion: AlphaSteer provides a theoretically grounded and empirically effective solution to the safety-utility trade-off in LLM activation steering, enabling safer deployment of LLMs in real-world applications.
Abstract: As LLMs are increasingly deployed in real-world applications, ensuring their ability to refuse malicious prompts, especially jailbreak attacks, is essential for safe and reliable use. Recently, activation steering has emerged as an effective approach for enhancing LLM safety by adding a refusal direction vector to internal activations of LLMs during inference, which will further induce the refusal behaviors of LLMs. However, indiscriminately applying activation steering fundamentally suffers from the trade-off between safety and utility, since the same steering vector can also lead to over-refusal and degraded performance on benign prompts. Although prior efforts, such as vector calibration and conditional steering, have attempted to mitigate this trade-off, their lack of theoretical grounding limits their robustness and effectiveness. To better address the trade-off between safety and utility, we present a theoretically grounded and empirically effective activation steering method called AlphaSteer. Specifically, it considers activation steering as a learnable process with two principled learning objectives: utility preservation and safety enhancement. For utility preservation, it learns to construct a nearly zero vector for steering benign data, with the null-space constraints. For safety enhancement, it learns to construct a refusal direction vector for steering malicious data, with the help of linear regression. Experiments across multiple jailbreak attacks and utility benchmarks demonstrate the effectiveness of AlphaSteer, which significantly improves the safety of LLMs without compromising general capabilities. Our codes are available at https://github.com/AlphaLab-USTC/AlphaSteer.
[1005] Scalable Back-Propagation-Free Training of Optical Physics-Informed Neural Networks
Yequan Zhao, Xinling Yu, Xian Xiao, Zhixiong Chen, Ziyue Liu, Geza Kurczveil, Raymond G. Beausoleil, Sijia Liu, Zheng Zhang
Main category: cs.LG
TL;DR: A BP-free framework for training physics-informed neural networks on photonic chips using sparse-grid Stein derivative estimator and tensor-train decomposition for real-time PDE solving.
Details
Motivation: Need for accelerated PDE solvers in resource-constrained scenarios for real-time decision making in physics intelligence and digital twins applications, with photonic computing offering ultra-high speed but facing challenges with photonic memory and device sizes.Method: Three innovations: (1) sparse-grid Stein derivative estimator to avoid backpropagation in PINN loss evaluation, (2) dimension-reduced zeroth-order optimization via tensor-train decomposition for better scalability and convergence, (3) scalable on-chip photonic PINN training accelerator design using photonic tensor cores.
Result: Validated on low- and high-dimensional PDE benchmarks; pre-silicon simulation shows significant performance benefits including real-time training and huge chip area reduction.
Conclusion: Proposed framework enables training real-size PINNs on silicon photonic platforms with BP-free approach, achieving real-time performance for physics intelligence applications.
Abstract: Physics intelligence and digital twins often require rapid and repeated performance evaluation of various engineering systems (e.g. robots, autonomous vehicles, semiconductor chips) to enable (almost) real-time actions or decision making. This has motivated the development of accelerated partial differential equation (PDE) solvers, in resource-constrained scenarios if the PDE solvers are to be deployed on the edge. Physics-informed neural networks (PINNs) have shown promise in solving high-dimensional PDEs, but the training time on state-of-the-art digital hardware (e.g., GPUs) is still orders-of-magnitude longer than the latency required for enabling real-time decision making. Photonic computing offers a potential solution to address this huge latency gap because of its ultra-high operation speed. However, the lack of photonic memory and the large device sizes prevent training real-size PINNs on photonic chips. This paper proposes a completely back-propagation-free (BP-free) and highly salable framework for training real-size PINNs on silicon photonic platforms. Our approach involves three key innovations: (1) a sparse-grid Stein derivative estimator to avoid the BP in the loss evaluation of a PINN, (2) a dimension-reduced zeroth-order optimization via tensor-train decomposition to achieve better scalability and convergence in BP-free training, and (3) a scalable on-chip photonic PINN training accelerator design using photonic tensor cores. We validate our numerical methods on both low- and high-dimensional PDE benchmarks. Through pre-silicon simulation based on real device parameters, we further demonstrate the significant performance benefit (e.g., real-time training, huge chip area reduction) of our photonic accelerator.
[1006] These Are Not All the Features You Are Looking For: A Fundamental Bottleneck in Supervised Pretraining
Xingyu Alice Yang, Jianyu Zhang, Léon Bottou
Main category: cs.LG
TL;DR: The paper proposes an inexpensive ensembling strategy to address transfer bias in pretrained models by aggregating multiple models to generate richer feature representations, improving transfer accuracy by 9% without extra pretraining cost.
Details
Motivation: Pretrained models often fail to fully cover features needed for unseen data in transfer learning due to sparse representations that retain only minimal features for initial training, discarding potentially useful ones for downstream transfer. This creates transfer bias when tasks have unclear relatedness.Method: Proposes an inexpensive ensembling strategy that aggregates multiple models to generate richer feature representations. The approach doesn’t require extra pretraining cost and is validated across various deep learning architectures including ResNet.
Result: On ResNet, the ensembling approach yields a 9% improvement in transfer accuracy without incurring extra pretraining cost. Empirical evidence from range of deep learning studies confirms the phenomenon is pervasive across modern architectures.
Conclusion: Relying solely on large pretrained networks is not always the most effective way to improve model generalization. Instead, fostering richer, more diverse representations through model ensembles can substantially enhance transfer learning performance.
Abstract: Transfer learning is widely used to adapt large pretrained models to new tasks with only a small amount of new data. However, a challenge persists – the features from the original task often do not fully cover what is needed for unseen data, especially when the relatedness of tasks is not clear. Since deep learning models tend to learn very sparse representations, they retain only the minimal features required for the initial training while discarding potentially ones for downstream transfer. A theoretical framework developed in this work demonstrates that such pretraining captures inconsistent aspects of the data distribution, therefore, inducing transfer bias. To address this limitation, we propose an inexpensive ensembling strategy that aggregates multiple models to generate richer feature representations. On ResNet, this approach yields a $9%$ improvement in transfer accuracy without incurring extra pretraining cost. We also present empirical evidence from a range of deep learning studies, confirming that the phenomenon is pervasive across modern deep learning architectures. These results suggests that relying solely on large pretrained networks is not always the most effective way to improve model generalization. Instead, fostering richer, more diverse representations – e.g. - through model ensembles – can substantially enhance transfer learning performance.
[1007] Remasking Discrete Diffusion Models with Inference-Time Scaling
Guanghan Wang, Yair Schiff, Subham Sekhar Sahoo, Volodymyr Kuleshov
Main category: cs.LG
TL;DR: ReMDM introduces a remasking diffusion sampler that enables iterative refinement in masked discrete diffusion models, allowing tokens to be updated during generation and providing inference-time compute scaling.
Details
Motivation: Modern masked discrete diffusion models lack iterative refinement capability - once a token is generated, it cannot be updated even if it introduces an error, limiting their performance compared to autoregressive models.Method: ReMDM sampler applies to pretrained masked diffusion models via a principled approach derived from discrete diffusion with custom remasking backward process, enabling tokens to be remasked and regenerated during sampling.
Result: ReMDM achieves inference-time compute scaling: with more sampling steps, it approaches autoregressive model quality; with limited compute, it maintains better quality than standard masked diffusion. It improves sample quality for discretized images and enables better diffusion guidance in scientific domains like molecule design.
Conclusion: ReMDM addresses a fundamental limitation of masked discrete diffusion by enabling iterative refinement, pushing the Pareto frontier of controllability and bridging the gap between diffusion and autoregressive models through compute scaling.
Abstract: Part of the success of diffusion models stems from their ability to perform iterative refinement, i.e., repeatedly correcting outputs during generation. However, modern masked discrete diffusion lacks this capability: when a token is generated, it cannot be updated again, even when it introduces an error. Here, we address this limitation by introducing the remasking diffusion model (ReMDM) sampler, a method that can be applied to pretrained masked diffusion models in a principled way and that is derived from a discrete diffusion model with a custom remasking backward process. Most interestingly, ReMDM endows discrete diffusion with a form of inference-time compute scaling. By increasing the number of sampling steps, ReMDM generates natural language outputs that approach the quality of autoregressive models, whereas when the computation budget is limited, ReMDM better maintains quality. ReMDM also improves sample quality of masked diffusion models for discretized images, and in scientific domains such as molecule design, ReMDM facilitates diffusion guidance and pushes the Pareto frontier of controllability relative to classical masking and uniform noise diffusion. We provide the code along with a blog post on the project page: https://guanghanwang.com/remdm
[1008] mTSBench: Benchmarking Multivariate Time Series Anomaly Detection and Model Selection at Scale
Xiaona Zhou, Constantin Brif, Ismini Lourentzou
Main category: cs.LG
TL;DR: mTSBench is the largest benchmark for multivariate time series anomaly detection, evaluating 24 detectors including LLM-based methods, finding no single best detector and highlighting need for better model selection strategies.
Details
Motivation: Multivariate time series anomaly detection is challenging due to high-dimensional dependencies, cross-correlations, and scarcity of labeled anomalies. Existing benchmarks are limited, and there's a need for comprehensive evaluation to understand detector performance and model selection effectiveness.Method: Created mTSBench with 344 labeled time series across 19 datasets from various domains. Evaluated 24 anomaly detectors including two publicly available LLM-based methods for multivariate time series. Benchmarked three recent model selection methods against this comprehensive dataset.
Result: No single detector dominates across all datasets, confirming prior findings. Even the strongest model selection methods remain far from optimal performance, highlighting significant gaps in current approaches.
Conclusion: There’s an outstanding need for robust, generalizable model selection strategies in multivariate time series anomaly detection. The benchmark is open-sourced to encourage future research in this direction.
Abstract: Anomaly detection in multivariate time series is essential across domains such as healthcare, cybersecurity, and industrial monitoring, yet remains fundamentally challenging due to high-dimensional dependencies, the presence of cross-correlations between time-dependent variables, and the scarcity of labeled anomalies. We introduce mTSBench, the largest benchmark to date for multivariate time series anomaly detection and model selection, consisting of 344 labeled time series across 19 datasets from a wide range of application domains. We comprehensively evaluate 24 anomaly detectors, including the only two publicly available large language model-based methods for multivariate time series. Consistent with prior findings, we observe that no single detector dominates across datasets, motivating the need for effective model selection. We benchmark three recent model selection methods and find that even the strongest of them remain far from optimal. Our results highlight the outstanding need for robust, generalizable selection strategies. We open-source the benchmark at https://plan-lab.github.io/mtsbench to encourage future research.
[1009] Latent Domain Modeling Improves Robustness to Geographic Shifts
Ruth Crasto, Esther Rolf
Main category: cs.LG
TL;DR: Proposes a framework for geographic distribution shift using location encoders to model continuous latent domains, improving worst-group performance on geo-tagged image datasets.
Details
Motivation: Geographic distribution shift causes uneven generalization across spatial groups when training and inference distributions differ. Existing methods either use discrete domain labels ignoring geographic coordinates, or use coordinates for overall performance but not specifically for domain generalization.Method: Framework uses location encoders to model continuous latent domain assignment, then conditions the main task predictor on these jointly-trained latents. This allows modeling geographic distribution shift as continuous rather than discrete domains.
Result: Achieves significant improvements in worst-group performance on four diverse geo-tagged image datasets compared to existing domain adaptation and location-aware methods. Sets new state-of-the-art results on two WILDS benchmark datasets.
Conclusion: Modeling geographic distribution shift through continuous latent domains using location encoders effectively improves robustness and worst-group performance for geo-tagged image tasks.
Abstract: Geographic distribution shift arises when the distribution of locations on Earth in a training dataset is different from what is seen at inference time. Using standard empirical risk minimization (ERM) in this setting can lead to uneven generalization across different spatially-determined groups of interest such as continents or biomes. The most common approaches to tackling geographic distribution shift apply domain adaptation methods using discrete group labels, ignoring geographic coordinates that are often available as metadata. On the other hand, modeling methods that integrate geographic coordinates have been shown to improve overall performance, but their impact on geographic domain generalization has not been studied. In this work, we propose a general modeling framework for improving robustness to geographic distribution shift. The key idea is to model continuous, latent domain assignment using location encoders and to condition the main task predictor on the jointly-trained latents. On four diverse geo-tagged image datasets with different group splits, we show that instances of our framework achieve significant improvements in worst-group performance compared to existing domain adaptation and location-aware modeling methods. In particular, we achieve new state-of-the-art results on two datasets from the WILDS benchmark.
[1010] Theoretical Modeling of Large Language Model Self-Improvement Training Dynamics Through Solver-Verifier Gap
Yifan Sun, Yushan Liang, Zhen Zhang, Xin Liu, Jiaye Teng
Main category: cs.LG
TL;DR: Theoretical framework models training dynamics of LLM self-improvement using solver-verifier gap concept, showing how to quantify capability limits and analyze external data effects.
Details
Motivation: Self-improvement techniques enhance LLM performance without external data, but how LLM performances evolve during this process remains underexplored. The paper aims to theoretically model these training dynamics.Method: Theoretical modeling of self-improvement training dynamics using the concept of solver-verifier gap. Framework models entire training trajectory and quantifies capability limits by fitting theoretical models to experimental results. Also extends analysis to investigate external data influence.
Result: Validated theoretical framework on various LLMs and datasets. Found that under limited external data regimes, such data can be utilized at any stage without significantly affecting final performances, aligning with empirical observations.
Conclusion: Provides theoretical understanding of self-improvement dynamics in LLMs, offering framework to quantify capability limits and analyze data utilization strategies.
Abstract: Self-improvement is a significant techniques within the realm of large language model (LLM), aiming to enhance the LLM performance without relying on external data. Despite its significance, generally how LLM performances evolve during the self-improvement process remains underexplored. In this paper, we theoretically model the training dynamics of self-improvement via the concept of solver-verifier gap. This is inspired by the conjecture that the performance enhancement of self-improvement stems from the gap between LLM’s solver capability and verifier capability. Based on the theoretical framework, we further show how to model the entire training trajectory. This framework allows quantifying the capability limit of self-improvement by fitting the theoretical model to the experiment results. We validate the effectiveness of the theoretical framework on various LLMs and datasets. Beyond self-improvement, we extend our analysis to investigate how external data influences these dynamics within the framework. Notably, we find that under limited external data regimes, such external data can be utilized at any stage without significantly affecting final performances, which accords with the empirical observations.
[1011] Probabilistic Forecasting via Autoregressive Flow Matching
Ahmed ElGazzar, Marcel van Gerven
Main category: cs.LG
TL;DR: FlowTime: A flow-based generative model for probabilistic forecasting of multivariate time series using flow matching framework.
Details
Motivation: To develop a generative model for probabilistic forecasting of multivariate time series that can capture complex multi-modal conditional distributions while maintaining benefits of autoregressive models like strong extrapolation and well-calibrated uncertainty.Method: Decomposes joint distribution of future observations into sequence of conditional densities, each modeled via shared flow transforming simple base distribution into next observation distribution conditioned on covariates. Uses flow matching framework for scalable, simulation-free learning.
Result: Demonstrated effectiveness on multiple dynamical systems and real-world forecasting tasks, showing ability to capture complex distributions while maintaining autoregressive benefits.
Conclusion: FlowTime combines benefits of autoregressive models with modern transport-based generative modeling capabilities for improved probabilistic time series forecasting.
Abstract: In this work, we propose FlowTime, a generative model for probabilistic forecasting of multivariate timeseries data. Given historical measurements and optional future covariates, we formulate forecasting as sampling from a learned conditional distribution over future trajectories. Specifically, we decompose the joint distribution of future observations into a sequence of conditional densities, each modeled via a shared flow that transforms a simple base distribution into the next observation distribution, conditioned on observed covariates. To achieve this, we leverage the flow matching (FM) framework, enabling scalable and simulation-free learning of these transformations. By combining this factorization with the FM objective, FlowTime retains the benefits of autoregressive models – including strong extrapolation performance, compact model size, and well-calibrated uncertainty estimates – while also capturing complex multi-modal conditional distributions, as seen in modern transport-based generative models. We demonstrate the effectiveness of FlowTime on multiple dynamical systems and real-world forecasting tasks.
[1012] Optimas: Optimizing Compound AI Systems with Globally Aligned Local Rewards
Shirley Wu, Parth Sarthi, Shiyu Zhao, Aaron Lee, Herumb Shandilya, Adrian Mladenic Grobelnik, Nurendra Choudhary, Eddie Huang, Karthik Subbian, Linjun Zhang, Diyi Yang, James Zou, Jure Leskovec
Main category: cs.LG
TL;DR: Optimas is a unified framework for optimizing compound AI systems by maintaining local reward functions per component that align with global system performance, enabling independent optimization of heterogeneous configurations.
Details
Motivation: Compound AI systems integrating multiple components (LLMs, specialized tools, traditional ML models) are increasingly used for complex tasks, but optimizing them is challenging due to non-differentiable structures and diverse configuration types across components.Method: Optimas maintains one Local Reward Function (LRF) per component, each satisfying a local-global alignment property where each component’s local reward correlates with global system performance. In each iteration, Optimas adapts LRFs to maintain this property while maximizing each component’s local reward, enabling independent updates of heterogeneous configurations.
Result: Extensive evaluations across five real-world compound systems show Optimas outperforms strong baselines by an average improvement of 11.92%.
Conclusion: Optimas offers a general and effective approach for improving compound AI systems by enabling coordinated optimization of heterogeneous components through local reward functions that align with global performance.
Abstract: Compound AI systems integrating multiple components, such as Large Language Models, specialized tools, and traditional machine learning models, are increasingly deployed to solve complex real-world tasks. However, optimizing compound systems remains challenging due to their non-differentiable structures and diverse configuration types across components, including prompts, hyperparameters, and model parameters. To address this challenge, we propose Optimas, a unified framework for effective optimization of compound systems. The core idea of Optimas is to maintain one Local Reward Function (LRF) per component, each satisfying a local-global alignment property, i.e., each component’s local reward correlates with the global system performance. In each iteration, Optimas efficiently adapts the LRFs to maintain this property while simultaneously maximizing each component’s local reward. This approach enables independent updates of heterogeneous configurations using the designated optimization method, while ensuring that local improvements consistently lead to performance gains. We present extensive evaluations across five real-world compound systems to demonstrate that Optimas outperforms strong baselines by an average improvement of 11.92%, offering a general and effective approach for improving compound systems. Our website is at https://optimas.stanford.edu.
[1013] ASIDE: Architectural Separation of Instructions and Data in Language Models
Egor Zverev, Evgenii Kortukov, Alexander Panfilov, Alexandra Volkova, Soroush Tabesh, Sebastian Lapuschkin, Wojciech Samek, Christoph H. Lampert
Main category: cs.LG
TL;DR: ASIDE introduces an architectural element that separates instruction and data tokens via orthogonal rotation of embeddings, improving prompt injection robustness without performance loss.
Details
Motivation: Large language models lack intrinsic safety features and are vulnerable to prompt injection attacks due to the absence of clear separation between instructions and data at the token embedding level.Method: ASIDE applies an orthogonal rotation to the embeddings of data tokens, creating distinct representations for instructions vs. data without adding parameters. Models are instruction-tuned with this modified architecture.
Result: ASIDE achieves substantially higher instruction-data separation without performance loss and makes models more robust to prompt injection benchmarks, even without dedicated safety training.
Conclusion: ASIDE provides an effective architectural solution to improve LLM safety against prompt injection by creating clear separation between instructions and data at the embedding level.
Abstract: Despite their remarkable performance, large language models lack elementary safety features, making them susceptible to numerous malicious attacks. In particular, previous work has identified the absence of an intrinsic separation between instructions and data as the root cause of the success of prompt injection attacks. In this work, we propose a new architectural element, ASIDE, that allows language models to clearly separate instructions and data at the level of token embeddings. ASIDE applies an orthogonal rotation to the embeddings of data tokens, thus creating clearly distinct representations of instructions and data tokens without introducing any additional parameters. As we demonstrate experimentally across a range of models, instruction-tuning LLMs with ASIDE (1) achieves substantially higher instruction-data separation without performance loss and (2) makes the models more robust to prompt injection benchmarks, even without dedicated safety training. Additionally, we provide insights into the mechanism underlying our method through an analysis of the model representations. The source code and training scripts are openly accessible at https://github.com/egozverev/aside.
[1014] XiChen: A global weather observation-to-forecast machine learning system via four-dimensional variational gradient-guided flexible assimilation
Wuxin Wang, Weicheng Ni, Lilan Huang, Tao Hao, Ben Fei, Shuo Ma, Taikang Yuan, Yanlai Zhao, Kefeng Deng, Xiaoyong Li, Hongze Leng, Boheng Duan, Lei Bai, Weimin Zhang, Junqiang Song, Kaijun Ren
Main category: cs.LG
TL;DR: XiChen is an ML-based global weather forecasting system that uses 4DVar gradient-guided assimilation to flexibly handle diverse observations without requiring observation-specific encoders or retraining when observation sources change.
Details
Motivation: Current ML weather forecasting systems still depend on NWP-generated initial conditions, and end-to-end ML models often require observation-specific encoders that need redesign/retraining when observation sources change, limiting operational robustness.Method: Uses four-dimensional variational (4DVar) gradient-guided flexible assimilation where the gradient of the 4DVar cost function serves as a physically grounded interface mapping heterogeneous observations into a common state space.
Result: The system achieves forecasting metrics competitive with operational NWP systems and can flexibly assimilate diverse conventional and raw satellite observations while preserving physical consistency.
Conclusion: Provides a practical and physically consistent route toward operational ML-based global weather forecasting systems that can handle heterogeneous and evolving observations.
Abstract: Machine Learning (ML) has shown great promise in revolutionizing weather forecasting, yet most ML systems still rely on initial conditions generated by Numerical Weather Prediction (NWP) systems. End-to-end ML models aim to eliminate this dependency, but they often rely on observation-specific encoders and require redesign or retraining when observation sources change, thereby limiting their operational robustness. Here, we introduce XiChen, a global weather observation-to-forecast ML system via four-dimensional variational (4DVar) gradient-guided flexible assimilation. We demonstrate that the gradient of the 4DVar cost function serves as a physically grounded interface that maps heterogeneous observations into a common state space. This novel formulation enables XiChen to flexibly assimilate diverse conventional and raw satellite observations while preserving physical consistency. Experiments show that the system achieves forecasting metrics competitive with operational NWP systems. This work provides a practical and physically consistent route toward operational ML-based global weather forecasting systems with heterogeneous and evolving observations.
[1015] LogicXGNN: Grounded Logical Rules for Explaining Graph Neural Networks
Chuqin Geng, Ziyu Zhao, Zhaoyue Wang, Haolin Ye, Yuhe Jiang, Xujie Si
Main category: cs.LG
TL;DR: LogicXGNN is a post-hoc framework for Graph Neural Networks that constructs logical rules over reliable predicates to ensure effective grounding of explanations in observable data.
Details
Motivation: Existing rule-based explanations for GNNs often operate in uninterpretable concept spaces, overlooking grounding quality for end users in final subgraph explanations, leading to explanations that may appear faithful but be unreliable in practice.Method: Proposes LogicXGNN, a post-hoc framework that constructs logical rules over reliable predicates explicitly designed to capture the GNN’s message-passing structure. Introduces data-grounded fidelity (Fid_D) metric that evaluates explanations in their final-graph form, along with complementary utility metrics like coverage and validity.
Result: LogicXGNN improves Fid_D by over 20% on average relative to state-of-the-art methods while being 10-100× faster. Demonstrates strong scalability and utility performance, producing explanations faithful to the model’s logic and reliably grounded in observable data.
Conclusion: LogicXGNN addresses the grounding gap in GNN explanations by ensuring explanations are both faithful to the model’s logic and reliably grounded in observable data through logical rules over reliable predicates.
Abstract: Existing rule-based explanations for Graph Neural Networks (GNNs) provide global interpretability but often optimize and assess fidelity in an intermediate, uninterpretable concept space, overlooking grounding quality for end users in the final subgraph explanations. This gap yields explanations that may appear faithful yet be unreliable in practice. To this end, we propose LogicXGNN, a post-hoc framework that constructs logical rules over reliable predicates explicitly designed to capture the GNN’s message-passing structure, thereby ensuring effective grounding. We further introduce data-grounded fidelity ($\textit{Fid}{\mathcal{D}}$), a realistic metric that evaluates explanations in their final-graph form, along with complementary utility metrics such as coverage and validity. Across extensive experiments, LogicXGNN improves $\textit{Fid}{\mathcal{D}}$ by over 20% on average relative to state-of-the-art methods while being 10-100 $\times$ faster. With strong scalability and utility performance, LogicXGNN produces explanations that are faithful to the model’s logic and reliably grounded in observable data. Our code is available at https://github.com/allengeng123/LogicXGNN/.
[1016] Geometric Reasoning in the Embedding Space
Jan Hůla, David Mojžíšek, Jiří Janeček, David Herel, Mikoláš Janota
Main category: cs.LG
TL;DR: Graph Neural Networks and Transformers can learn geometric reasoning by predicting point positions from constraints and forming hidden figures in embedding space.
Details
Motivation: To investigate whether neural networks can learn to reason about geometric constraints and spatial relationships, specifically predicting point positions from constraint descriptions.Method: Train Graph Neural Networks and Transformers on a task of predicting spatial positions of points in a discrete 2D grid from constraints that uniquely describe hidden figures containing these points.
Result: Both models successfully predict point positions and form the hidden figures in embedding space during reasoning. GNNs perform significantly better than Transformers and are easier to scale. Both models recover grid structure in embeddings.
Conclusion: Neural networks can learn geometric reasoning, with GNNs being particularly effective for spatial constraint problems. The models naturally organize embeddings to reflect grid structure during training.
Abstract: In this contribution, we demonstrate that Graph Neural Networks and Transformers can learn to reason about geometric constraints. We train them to predict spatial position of points in a discrete 2D grid from a set of constraints that uniquely describe hidden figures containing these points. Both models are able to predict the position of points and interestingly, they form the hidden figures described by the input constraints in the embedding space during the reasoning process. Our analysis shows that both models recover the grid structure during training so that the embeddings corresponding to the points within the grid organize themselves in a 2D subspace and reflect the neighborhood structure of the grid. We also show that the Graph Neural Network we design for the task performs significantly better than the Transformer and is also easier to scale.
[1017] FlashKAT: Understanding and Addressing Performance Bottlenecks in the Kolmogorov-Arnold Transformer
Matthew Raffel, Lizhong Chen
Main category: cs.LG
TL;DR: FlashKAT addresses memory bottlenecks in Kolmogorov-Arnold Transformers by restructuring kernels to minimize slow memory access and atomic operations, achieving 86.5x training speedup.
Details
Motivation: Kolmogorov-Arnold Networks (KANs) offer better expressiveness and interpretability than MLPs but suffer from training instability and computational slowness. Kolmogorov-Arnold Transformers (KATs) with Group-Rational KANs achieve comparable FLOPs to traditional Transformers but remain 123x slower in training due to memory bottlenecks, specifically inefficient gradient accumulations in backward passes.Method: The paper identifies memory stalls as the root cause of KAT slowdowns, tracing them to inefficient gradient accumulations in GR-KAN backward passes. FlashKAT is proposed with restructured kernels that minimize accesses to slow memory and reduce usage of atomic add operations, optimizing memory bandwidth utilization.
Result: FlashKAT achieves up to 86.5x training speedup over state-of-the-art KAT implementations while also reducing rounding errors in gradient computation, making KATs more practical for large-scale applications.
Conclusion: Memory bottlenecks, not just FLOPs, are critical for KAT performance. FlashKAT’s kernel optimizations effectively address these memory issues, enabling practical deployment of Kolmogorov-Arnold Transformers with significant speed improvements and numerical stability.
Abstract: The Kolmogorov-Arnold Network (KAN) has been gaining popularity as an alternative to the multilayer perceptron (MLP) due to its greater expressiveness and interpretability. Even so, KAN suffers from training instability and being orders of magnitude slower due to its increased computational cost, limiting its applicability to large-scale tasks. Recently, the Kolmogorov-Arnold Transformer (KAT) has been proposed, achieving FLOPs comparable to traditional Transformer models with MLPs by leveraging Group-Rational KAN (GR-KAN). Unfortunately, despite the comparable FLOPs, our testing shows that KAT remains 123x slower during training, indicating that there are other performance bottlenecks beyond FLOPs. In this paper, we conduct a series of experiments to understand the root cause of the slowdown in KAT. We uncover that the slowdown can be isolated to memory stalls, linked more specifically to inefficient gradient accumulations in the backward pass of GR-KAN. To address this memory bottleneck, we propose FlashKAT, which minimizes accesses to slow memory and the usage of atomic adds through a restructured kernel. Evaluations show that FlashKAT achieves up to an 86.5x training speedup over state-of-the-art KAT while reducing rounding errors in gradient computation.
[1018] NOCTA: Non-Greedy Objective Cost-Tradeoff Acquisition for Longitudinal Data
Dzung Dinh, Boqi Chen, Yunni Qu, Marc Niethammer, Junier Oliva
Main category: cs.LG
TL;DR: NOCTA is a framework for sequential feature acquisition in longitudinal prediction that balances information gain with acquisition costs, using novel NOCT objective and two estimators.
Details
Motivation: In critical domains like healthcare, features have acquisition costs (time, money, risk) and longitudinal prediction faces challenges with evolving features/labels and permanently unavailable missing measurements.Method: Proposes NOCTA framework with NOCT objective evaluating candidate feature-time acquisitions by expected predictive loss + acquisition cost. Develops two estimators: NOCT-Contrastive (learns embeddings of partial observations) and NOCT-Amortized (directly predicts NOCT with neural network).
Result: Experiments on synthetic and real-world medical datasets show both NOCTA estimators outperform existing baselines, achieving higher accuracy at lower acquisition costs.
Conclusion: NOCTA effectively addresses the feature acquisition problem in longitudinal prediction by balancing information gain with costs, with both proposed estimators showing strong performance.
Abstract: In many critical domains, features are not freely available at inference time: each measurement may come with a cost of time, money, and risk. Longitudinal prediction further complicates this setting because both features and labels evolve over time, and missing measurements at earlier timepoints may become permanently unavailable. We propose NOCTA, a Non-Greedy Objective Cost-Tradeoff Acquisition framework that sequentially acquires the most informative features at inference time while accounting for both temporal dynamics and acquisition cost. NOCTA is driven by a novel objective, NOCT, which evaluates a candidate set of future feature-time acquisitions by its expected predictive loss together with its acquisition cost. Since NOCT depends on unobserved future trajectories at inference time, we develop two complementary estimators: (i) NOCT-Contrastive, which learns an embedding of partial observations utilizing the induced distribution over future acquisitions, and (ii) NOCT-Amortized, which directly predicts NOCT for candidate plans with a neural network. Experiments on synthetic and real-world medical datasets demonstrate that both NOCTA estimators outperform existing baselines, achieving higher accuracy at lower acquisition costs.
[1019] Federated Hierarchical Reinforcement Learning for Adaptive Traffic Signal Control
Yongjie Fu, Lingyun Zhong, Zifan Li, Xuan Di
Main category: cs.LG
TL;DR: HFRL: Hierarchical Federated Reinforcement Learning for traffic signal control that groups similar intersections for more effective coordination than standard FedAvg in heterogeneous environments.
Details
Motivation: MARL for traffic signal control faces scalability issues with extensive data sharing, while traditional FL (FedAvg) struggles with heterogeneous intersections having varying traffic patterns, demands, and road structures.Method: Hierarchical Federated Reinforcement Learning (HFRL) uses clustering-based or optimization-based techniques to dynamically group intersections with similar characteristics and perform FedAvg independently within each group.
Result: HFRL consistently outperforms decentralized and standard federated RL approaches, achieves competitive/superior performance to centralized RL as network scale/heterogeneity increase, and identifies suitable grouping patterns based on network structure or traffic demand.
Conclusion: HFRL provides a robust framework for distributed, heterogeneous traffic control systems by enabling more effective coordination and scalability than standard FedAvg approaches.
Abstract: Multi-agent reinforcement learning (MARL) has shown promise for adaptive traffic signal control (ATSC), enabling multiple intersections to coordinate signal timings in real time. However, in large-scale settings, MARL faces constraints due to extensive data sharing and communication requirements. Federated learning (FL) mitigates these challenges by training shared models without directly exchanging raw data, yet traditional FL methods such as FedAvg struggle with highly heterogeneous intersections. Different intersections exhibit varying traffic patterns, demands, and road structures, so performing FedAvg across all agents is inefficient. To address this gap, we propose Hierarchical Federated Reinforcement Learning (HFRL) for ATSC. HFRL employs clustering-based or optimization-based techniques to dynamically group intersections and perform FedAvg independently within groups of intersections with similar characteristics, enabling more effective coordination and scalability than standard FedAvg.Our experiments on synthetic and real-world traffic networks demonstrate that HFRL consistently outperforms decentralized and standard federated RL approaches, and achieves competitive or superior performance compared to centralized RL as network scale and heterogeneity increase, particularly in real-world settings. The method also identifies suitable grouping patterns based on network structure or traffic demand, resulting in a more robust framework for distributed, heterogeneous systems.
[1020] Understanding Generalization in Diffusion Distillation via Probability Flow Distance
Huijie Zhang, Zijian Huang, Siyi Chen, Jinfan Zhou, Zekai Zhang, Peng Wang, Qing Qu
Main category: cs.LG
TL;DR: PFD is a novel metric for evaluating generalization in diffusion distillation that measures distribution distance via probability flow ODE mappings, revealing key behaviors like scaling from memorization to generalization and double descent dynamics.
Details
Motivation: Current evaluation of diffusion distillation models lacks practical, theoretically-grounded metrics for measuring generalization. Theoretical metrics are impractical for high-dimensional data, while practical metrics don't rigorously measure generalization.Method: Introduces Probability Flow Distance (PFD) - a metric that quantifies distribution distance by comparing noise-to-data mappings induced by probability flow ODEs. Applied to diffusion distillation to study generalization behaviors.
Result: Empirically uncovers key generalization behaviors: (1) quantitative scaling from memorization to generalization, (2) epoch-wise double descent training dynamics, and (3) bias-variance decomposition in diffusion distillation.
Conclusion: PFD provides a foundation for generalization studies in diffusion distillation and bridges them with diffusion training, offering both theoretical grounding and computational efficiency for evaluating model generalization.
Abstract: Diffusion distillation provides an effective approach for learning lightweight and few-steps diffusion models with efficient generation. However, evaluating their generalization remains challenging: theoretical metrics are often impractical for high-dimensional data, while no practical metrics rigorously measure generalization. In this work, we bridge this gap by introducing probability flow distance (\texttt{PFD}), a theoretically grounded and computationally efficient metric to measure generalization. Specifically, \texttt{PFD} quantifies the distance between distributions by comparing their noise-to-data mappings induced by the probability flow ODE. Using \texttt{PFD} under the diffusion distillation setting, we empirically uncover several key generalization behaviors, including: (1) quantitative scaling behavior from memorization to generalization, (2) epoch-wise double descent training dynamics, and (3) bias-variance decomposition. Beyond these insights, our work lays a foundation for generalization studies in diffusion distillation and bridges them with diffusion training.
[1021] A Parallel Alternative for Energy-Efficient Neural Network Training and Inferencing
Sudip K. Seal, Maksudul Alam, Jorge Ramirez, Sajal Dash, Hao Lu
Main category: cs.LG
TL;DR: Phantom parallelism reduces energy consumption in large neural network training by minimizing the energy-inefficient tensor parallelism component, achieving ~50% energy savings for feed-forward networks.
Details
Motivation: Energy efficiency in training and inference with large neural network models is a critical sustainability challenge. Traditional tensor parallelism is the most energy-inefficient component of large-scale training, motivating the need for alternative strategies.Method: Introduces phantom parallelism as an alternative to tensor parallelism. Derives new forward and backward propagation operators, implements them as custom autograd operations within an end-to-end phantom parallel training pipeline, and compares performance and energy-efficiency against conventional tensor parallel pipelines.
Result: Formal analyses predict lower bandwidth and FLOP counts, with empirical results on up to 256 GPUs showing ~50% reduction in energy consumption for training FFNs compared to conventional tensor parallel methods. Also demonstrates training smaller phantom models to same loss on fewer GPUs than larger tensor parallel models.
Conclusion: Phantom parallelism offers significant energy savings for large neural network training, particularly for feed-forward architectures, with potential for even greater savings through model size reduction and lower GPU requirements.
Abstract: Energy efficiency of training and inferencing with large neural network models is a critical challenge facing the future of sustainable large-scale machine learning workloads. This paper introduces an alternative strategy, called phantom parallelism, to minimize the net energy consumption of traditional tensor (model) parallelism, the most energy-inefficient component of large neural network training. The approach is presented in the context of feed-forward network architectures as a preliminary, but comprehensive, proof-of-principle study of the proposed methodology. We derive new forward and backward propagation operators for phantom parallelism, implement them as custom autograd operations within an end-to-end phantom parallel training pipeline and compare its parallel performance and energy-efficiency against those of conventional tensor parallel training pipelines. Formal analyses that predict lower bandwidth and FLOP counts are presented with supporting empirical results on up to 256 GPUs that corroborate these gains. Experiments are shown to deliver approximately 50% reduction in the energy consumed to train FFNs using the proposed phantom parallel approach when compared with conventional tensor parallel methods. Additionally, the proposed approach is shown to train smaller phantom models to the same model loss on smaller GPU counts as larger tensor parallel models on larger GPU counts offering the possibility for even greater energy savings.
[1022] Think2SQL: Reinforce LLM Reasoning Capabilities for Text2SQL
Simone Papicchio, Simone Rossi, Luca Cagliero, Paolo Papotti
Main category: cs.LG
TL;DR: This paper presents Think2SQL, a systematic study on enhancing Text-to-SQL reasoning using Reinforcement Learning with Verifiable Rewards (RLVR), focusing on reward design, advantage scaling, and model capacity trade-offs.
Details
Motivation: Large Language Models have advanced Text-to-SQL, but robust reasoning in complex multi-table environments remains challenging for parameter-efficient models. The paper aims to systematically inject reasoning capabilities into Text-to-SQL through RLVR.Method: The authors conduct empirical studies on RLVR for Text-to-SQL, analyzing reward density, advantage scaling, and model capacity. They propose execution-guided dense reward functions, analyze advantage calculation mechanics, evaluate cold start impacts, and map Pareto frontiers for training efficiency.
Result: The study yields four key insights: 1) execution-guided dense rewards outperform binary signals, 2) large models benefit from sparse rewards with aggressive scaling while smaller models need dense rewards with conservative scaling, 3) distillation doesn’t always improve RLVR performance, and 4) training efficiency frontiers are mapped. The resulting Think2SQL family (4B parameters) shows competitive reasoning capabilities.
Conclusion: The paper provides a blueprint for RLVR optimization in Text-to-SQL, demonstrating that systematic analysis of reward design, advantage scaling, and model capacity can significantly enhance reasoning capabilities in parameter-efficient models.
Abstract: While Large Language Models (LLMs) have advanced the state-of-the-art in Text-to-SQL, robust reasoning in complex, multi-table environments remains a bottleneck for parameter-efficient models. This paper presents a systematic empirical study on injecting reasoning capabilities into Text-to-SQL through the lens of Reinforcement Learning with Verifiable Rewards (RLVR). We uncover a critical interplay between reward density, advantage scaling, and model capacity. Our analysis yields four primary insights. First, we propose a novel execution-guided dense reward function that significantly outperforms binary signals and existing state-of-the-art rewards by providing granular feedback at the instance level. Second, we analyze the mechanics of advantage calculation, demonstrating that while large models thrive on sparse signals with aggressive advantage scaling, smaller models require dense rewards and conservative scaling to improve Text-to-SQL performance. Third, we evaluate the impact of cold start, showing that distillation does not always improve RLVR performance and that supervised, fine-tuned models are prone to distributional mimicry. Fourth, we map the Pareto frontier of training efficiency, providing insights for optimizing Text-to-SQL reasoning under computational constraints. Our findings culminate in the Think2SQL family: our 4B-parameter model demonstrates reasoning capabilities competitive with state-of-the-art models such as o3. We release our models, datasets, and code to create a blueprint for RLVR optimization in Text-to-SQL at https://anonymous.4open.science/r/Think2SQL-3B7F.
[1023] Evaluating Autoencoders for Parametric and Invertible Multidimensional Projections
Frederik L. Dennig, Nina Geyer, Daniela Blumberg, Yannick Metz, Daniel A. Keim
Main category: cs.LG
TL;DR: Autoencoders can create parametric and invertible multidimensional data projections, offering smoother results than feed-forward networks with controllable smoothing.
Details
Motivation: Neural networks can create parametric and invertible projections, but these properties haven't been explored simultaneously for arbitrary projection methods. The paper aims to evaluate autoencoder architectures for creating such projections.Method: Evaluate three autoencoder architectures trained to learn mappings into 2D space and inverse mappings back to original space. Use customized loss function and compare with feed-forward neural networks on four datasets using t-SNE projections.
Result: Autoencoders with customized loss functions create smoother parametric and inverse projections than feed-forward neural networks, while giving users control over smoothing strength.
Conclusion: Autoencoders are effective for creating parametric and invertible multidimensional data projections, offering advantages over traditional feed-forward networks for visualization and data generation tasks.
Abstract: Recently, neural networks have gained attention for creating parametric and invertible multidimensional data projections. Parametric projections allow for embedding previously unseen data without recomputing the projection as a whole, while invertible projections enable the generation of new data points. However, these properties have never been explored simultaneously for arbitrary projection methods. We evaluate three autoencoder (AE) architectures for creating parametric and invertible projections. Based on a given projection, we train AEs to learn a mapping into 2D space and an inverse mapping into the original space. We perform a quantitative and qualitative comparison on four datasets of varying dimensionality and pattern complexity using t-SNE. Our results indicate that AEs with a customized loss function can create smoother parametric and inverse projections than feed-forward neural networks while giving users control over the strength of the smoothing effect.
[1024] SIMSHIFT: A Benchmark for Adapting Neural Surrogates to Distribution Shifts
Paul Setinek, Gianluca Galletti, Thomas Gross, Dominik Schnürer, Johannes Brandstetter, Werner Zellinger
Main category: cs.LG
TL;DR: SIMSHIFT benchmark introduces industrial simulation tasks to evaluate neural PDE surrogates under distribution shifts, with UDA methods applied to improve generalization.
Details
Motivation: Neural PDE surrogates degrade on out-of-distribution configurations; UDA techniques from vision/language haven't been explored for complex engineering simulations.Method: Created SIMSHIFT benchmark with 4 industrial simulation tasks; extended established UDA methods to state-of-the-art neural surrogates and systematically evaluated them.
Result: Experiments highlight challenges of OOD neural surrogate modeling, demonstrate UDA potential in simulation, and reveal open problems for robust industrial applications.
Conclusion: SIMSHIFT enables systematic evaluation of neural surrogate robustness under distribution shifts, showing UDA’s promise but highlighting remaining challenges for industrial adoption.
Abstract: Neural surrogates for Partial Differential Equations (PDEs) often suffer significant performance degradation when evaluated on problem configurations outside their training distribution, such as new initial conditions or structural dimensions. While Unsupervised Domain Adaptation (UDA) techniques have been widely used in vision and language to generalize across domains without additional labeled data, their application to complex engineering simulations remains largely unexplored. In this work, we address this gap through two focused contributions. First, we introduce SIMSHIFT, a novel benchmark dataset and evaluation suite composed of four industrial simulation tasks spanning diverse processes and physics: hot rolling, sheet metal forming, electric motor design and heatsink design. Second, we extend established UDA methods to state-of-the-art neural surrogates and systematically evaluate them. Extensive experiments on SIMSHIFT highlight the challenges of out-of-distribution neural surrogate modeling, demonstrate the potential of UDA in simulation, and reveal open problems in achieving robust neural surrogates under distribution shifts in industrially relevant scenarios. Our codebase is available at https://github.com/psetinek/simshift
[1025] Efficient Attention via Pre-Scoring: Prioritizing Informative Keys in Transformers
Zhexiang Li, Haoyu Wang, Yutong Bao, David Woodruff
Main category: cs.LG
TL;DR: Pre-scoring framework improves approximate attention by assigning global importance scores to keys before hierarchical attention, enabling better token prioritization while maintaining subquadratic efficiency.
Details
Motivation: Efficient attention mechanisms for long-context transformers often miss globally important tokens, degrading modeling quality. There's a need for methods that can identify and prioritize structurally informative keys while maintaining computational efficiency.Method: Introduces a pre-scoring framework that assigns query-independent global importance priors to keys before applying hierarchical approximate attention. Uses clustering-based or leverage-style scoring to identify structurally informative keys and restricts computation to this prioritized subset. Integrated with HyperAttention for efficient implementation.
Result: On ChatGLM with 131k-token contexts, perplexity decreases from 12.0 to 9.5 under fixed interaction budget while retaining subquadratic efficiency. Clustering-based scoring outperforms leverage-based selection. Approach also works in Vision Transformers, preserving most baseline accuracy.
Conclusion: Pre-scoring improves efficiency-accuracy trade-off of approximate attention by better prioritizing informative keys without sacrificing scalability. The method generalizes across modalities (language and vision) and provides theoretical guarantees under planted-subspace models.
Abstract: Efficient attention mechanisms enable long-context transformers but often miss globally important tokens, degrading modeling quality. We introduce a pre-scoring framework that assigns a query-independent global importance prior to keys before applying hierarchical approximate attention. Using clustering-based or leverage-style scoring, pre-scoring identifies structurally informative keys and restricts computation to this prioritized subset. Integrated with HyperAttention, pre-scoring substantially improves approximation quality on long-context language modeling: on ChatGLM with 131k-token contexts, perplexity decreases from 12.0 to 9.5 under a fixed interaction budget while retaining subquadratic efficiency. Clustering-based scoring consistently outperforms leverage-based selection under identical key budgets. Beyond language, replacing self-attention in Vision Transformers preserves most of the baseline accuracy, showing that the approach generalizes across modalities. We provide structural guarantees under a planted-subspace model, showing that clustering recovers the same heavy-key sets as leverage-based methods. Overall, pre-scoring improves the efficiency-accuracy trade-off of approximate attention by better prioritizing informative keys without sacrificing scalability.
[1026] A-FloPS: Accelerating Diffusion Models via Adaptive Flow Path Sampler
Cheng Jin, Zhenyu Xiao, Yuantao Gu
Main category: cs.LG
TL;DR: A-FloPS is a training-free acceleration framework for diffusion models that reparameterizes sampling trajectories into flow-matching form with adaptive velocity decomposition, enabling high-quality generation with as few as 5 function evaluations.
Details
Motivation: Diffusion models achieve state-of-the-art generative performance but are computationally expensive due to iterative sampling. Existing training-free acceleration methods are limited by inefficient sampling trajectories, creating a need for more effective acceleration techniques.Method: A-FloPS reparameterizes pre-trained diffusion model sampling trajectories into flow-matching form and augments with adaptive velocity decomposition. It analytically maps diffusion scores to flow-compatible velocities and factorizes velocity field into linear drift and residual components with suppressed temporal variation.
Result: Extensive experiments on conditional image generation and text-to-image synthesis show A-FloPS consistently outperforms state-of-the-art training-free samplers in sample quality and efficiency. With only 5 function evaluations, it achieves substantially lower FID and generates sharper, more coherent images.
Conclusion: A-FloPS provides a versatile and effective solution for high-quality, low-latency generative modeling, improving both diffusion model acceleration and native flow-based generative models through its adaptive mechanism.
Abstract: Diffusion models deliver state-of-the-art generative performance across diverse modalities but remain computationally expensive due to their inherently iterative sampling process. Existing training-free acceleration methods typically improve numerical solvers for the reverse-time ODE, yet their effectiveness is fundamentally constrained by the inefficiency of the underlying sampling trajectories. We propose A-FloPS (Adaptive Flow Path Sampler), a principled, training-free framework that reparameterizes the sampling trajectory of any pre-trained diffusion model into a flow-matching form and augments it with an adaptive velocity decomposition. The reparameterization analytically maps diffusion scores to flow-compatible velocities, yielding integration-friendly trajectories without retraining. The adaptive mechanism further factorizes the velocity field into a linear drift term and a residual component whose temporal variation is actively suppressed, restoring the accuracy benefits of high-order integration even in extremely low-NFE regimes. Extensive experiments on conditional image generation and text-to-image synthesis show that A-FloPS consistently outperforms state-of-the-art training-free samplers in both sample quality and efficiency. Notably, with as few as $5$ function evaluations, A-FloPS achieves substantially lower FID and generates sharper, more coherent images. The adaptive mechanism also improves native flow-based generative models, underscoring its generality. These results position A-FloPS as a versatile and effective solution for high-quality, low-latency generative modeling.
[1027] Beyond the Mean: Fisher-Orthogonal Projection for Natural Gradient Descent in Large Batch Training
Yishun Lu, Wesley Armour
Main category: cs.LG
TL;DR: FOP (Fisher-Orthogonal Projection) is a novel optimization technique that enables effective second-order optimization at very large batch sizes by constructing variance-aware update directions using orthogonal gradient components under the Fisher metric.
Details
Motivation: Modern GPUs can handle extremely large batch sizes (tens of thousands of samples), but existing optimizers struggle at this scale. First-order methods lose effectiveness due to reduced gradient noise, while second-order methods like KFAC require excessive damping that washes out curvature information, reducing them to simple gradient descent.Method: FOP constructs a variance-aware update direction by leveraging gradients from two sub-batches. It enhances the average gradient with a component of the gradient difference that is orthogonal to the average under the Fisher-metric, restoring the effectiveness of second-order methods at very large batch sizes.
Result: FOP enables scalable training with improved generalization and faster convergence at very large batch sizes, overcoming the limitations of both first-order and existing second-order methods in large-batch optimization scenarios.
Conclusion: FOP provides an effective solution for large-batch optimization by maintaining the advantages of second-order methods while addressing stability issues, enabling practical use of very large batch sizes on modern GPU hardware.
Abstract: Modern GPUs are equipped with large amounts of high-bandwidth memory, enabling them to support mini-batch sizes of up to tens of thousands of training samples. However, most existing optimizers struggle to perform effectively at such a large batch size. As batch size increases, gradient noise decreases due to averaging over many samples, limiting the ability of first-order methods to escape sharp or suboptimal minima and reach the global minimum. Meanwhile, second-order methods like the natural gradient with Kronecker-Factored Approximate Curvature (KFAC) often require excessively high damping to remain stable at large batch sizes. This high damping effectively washes out the curvature information that gives these methods their advantage, reducing their performance to that of simple gradient descent. In this paper, we introduce Fisher-Orthogonal Projection (FOP), a novel technique that restores the effectiveness of the second-order method at very large batch sizes, enabling scalable training with improved generalization and faster convergence. FOP constructs a variance-aware update direction by leveraging gradients from two sub-batches, enhancing the average gradient with a component of the gradient difference that is orthogonal to the average under the Fisher-metric.
[1028] Transformers as Unsupervised Learning Algorithms: A study on Gaussian Mixtures
Zhiheng Chen, Ruofan Wu, Guanhua Fang
Main category: cs.LG
TL;DR: Transformers can learn to solve Gaussian Mixture Models (GMMs) through a shared backbone architecture, outperforming classical methods like EM and spectral algorithms while showing robustness to distribution shifts.
Details
Motivation: While transformers have shown remarkable capabilities in supervised learning tasks like in-context learning, their potential for unsupervised learning remains largely unexplored. The paper aims to investigate transformers' capabilities in solving fundamental unsupervised learning problems like Gaussian Mixture Models.Method: Proposes TGMM, a transformer-based learning framework that simultaneously learns to solve multiple GMM tasks using a shared transformer backbone. Theoretically proves transformers can approximate both EM algorithm and cubic tensor power iterations (core component of spectral methods).
Result: Empirical results show learned models effectively mitigate limitations of classical methods (EM, spectral algorithms) and exhibit reasonable robustness to distribution shifts. Theoretical proofs demonstrate transformers can approximate key unsupervised learning algorithms.
Conclusion: Transformers can serve as versatile tools for unsupervised learning, bridging the gap between practical success and theoretical understanding. The work positions transformers beyond supervised learning applications into fundamental unsupervised problems.
Abstract: The transformer architecture has demonstrated remarkable capabilities in modern artificial intelligence, among which the capability of implicitly learning an internal model during inference time is widely believed to play a key role in the under standing of pre-trained large language models. However, most recent works have been focusing on studying supervised learning topics such as in-context learning, leaving the field of unsupervised learning largely unexplored. This paper investigates the capabilities of transformers in solving Gaussian Mixture Models (GMMs), a fundamental unsupervised learning problem through the lens of statistical estimation. We propose a transformer-based learning framework called TGMM that simultaneously learns to solve multiple GMM tasks using a shared transformer backbone. The learned models are empirically demonstrated to effectively mitigate the limitations of classical methods such as Expectation-Maximization (EM) or spectral algorithms, at the same time exhibit reasonable robustness to distribution shifts. Theoretically, we prove that transformers can approximate both the EM algorithm and a core component of spectral methods (cubic tensor power iterations). These results bridge the gap between practical success and theoretical understanding, positioning transformers as versatile tools for unsupervised learning.
[1029] Your Reward Function for RL is Your Best PRM for Search: Unifying RL and Search-Based TTS
Can Jin, Yang Zhou, Qixin Zhang, Hongwu Peng, Di Zhang, Zihan Dong, Marco Pavone, Ligong Han, Zhang-Wei Hong, Tong Che, Dimitris N. Metaxas
Main category: cs.LG
TL;DR: AIRL-S unifies RL-based and search-based test-time scaling for LLMs by learning a dense, dynamic process reward model from correct reasoning traces without labeled data, using it both as RL critic and search heuristic.
Details
Motivation: Current test-time scaling methods for LLMs have limitations: RL methods suffer from instability and low sample efficiency with sparse rewards, while search-based methods require expensive labeled data for static process reward models that degrade under distribution shifts. There's a need to unify these approaches more effectively.Method: AIRL-S uses adversarial inverse reinforcement learning (AIRL) combined with group relative policy optimization (GRPO) to learn a dense, dynamic process reward model directly from correct reasoning traces, eliminating need for labeled intermediate data. The learned reward model serves dual purpose: as critic for RL rollouts and as heuristic to guide search algorithms.
Result: Across eight benchmarks (mathematics, scientific reasoning, code generation), AIRL-S improves performance by 9% on average over base model, matching GPT-4o. When integrated into search algorithms, the learned PRM consistently outperforms baseline PRMs trained with labeled data.
Conclusion: The reward function learned during RL training inherently represents the ideal process reward model for guiding downstream search, providing a robust and cost-effective solution for complex reasoning tasks in LLMs without requiring expensive labeled data.
Abstract: Test-time scaling (TTS) for large language models (LLMs) has thus far fallen into two largely separate paradigms: (1) reinforcement learning (RL) methods that optimize sparse outcome-based rewards, yet suffer from instability and low sample efficiency; and (2) search-based techniques guided by independently trained, static process reward models (PRMs), which require expensive human- or LLM-generated labels and often degrade under distribution shifts. In this paper, we introduce AIRL-S, the first natural unification of RL-based and search-based TTS. Central to AIRL-S is the insight that the reward function learned during RL training inherently represents the ideal PRM for guiding downstream search. Specifically, we leverage adversarial inverse reinforcement learning (AIRL) combined with group relative policy optimization (GRPO) to learn a dense, dynamic PRM directly from correct reasoning traces, entirely eliminating the need for labeled intermediate process data. At inference, the resulting PRM simultaneously serves as the critic for RL rollouts and as a heuristic to effectively guide search procedures, facilitating robust reasoning chain extension, mitigating reward hacking, and enhancing cross-task generalization. Experimental results across eight benchmarks, including mathematics, scientific reasoning, and code generation, demonstrate that our unified approach improves performance by 9 % on average over the base model, matching GPT-4o. Furthermore, when integrated into multiple search algorithms, our PRM consistently outperforms all baseline PRMs trained with labeled data. These results underscore that, indeed, your reward function for RL is your best PRM for search, providing a robust and cost-effective solution to complex reasoning tasks in LLMs.
[1030] Parallel Layer Normalization for Universal Approximation
Yunhao Ni, Yuxin Guo, Yuhe Liu, Wenxin Sun, Jie Luo, Wenjun Wu, Lei Huang
Main category: cs.LG
TL;DR: PLN-Nets (parallel layer normalization networks) achieve universal approximation while standard LN networks have limited expressive power, with analysis extended to RMSNorm and position-wise feed-forward networks.
Details
Motivation: To understand the approximation capabilities of neural networks combining layer normalization with linear layers, particularly comparing parallel LN architectures vs standard LN, and extending analysis to modern architectures used in Transformers and RNNs.Method: Theoretical analysis of PLN-Nets (networks with two linear layers and parallel layer normalizations between them), proving universal approximation properties. Analysis includes approximation rates under L∞ and Sobolev norms, extension to RMSNorm, and application to position-wise feed-forward networks. Empirical experiments to explore additional potentials.
Result: PLN-Nets achieve universal approximation while standard LN networks have strictly limited expressive power. Theoretical bounds established for shallow and deep PLN-Nets, with extensions to RMSNorm and position-wise feed-forward networks. Empirical results support theoretical findings.
Conclusion: Parallel layer normalization architectures enable universal approximation capabilities that standard LN lacks, with implications for understanding expressive power of normalization techniques in modern neural architectures like Transformers.
Abstract: This paper studies the approximation capabilities of neural networks that combine layer normalization (LN) with linear layers. We prove that networks consisting of two linear layers with parallel layer normalizations (PLNs) inserted between them (referred to as PLN-Nets) achieve universal approximation, whereas architectures that use only standard LN exhibit strictly limited expressive power.We further analyze approximation rates of shallow and deep PLN-Nets under the $L^\infty$ norm as well as in Sobolev norms. Our analysis extends beyond LN to RMSNorm, and from standard MLPs to position-wise feed-forward networks, the core building blocks used in RNNs and Transformers.Finally, we provide empirical experiments to explore other possible potentials of PLN-Nets.
[1031] MetaCluster: Enabling Deep Compression of Kolmogorov-Arnold Network
Matthew Raffel, Adwaith Renjith, Lizhong Chen
Main category: cs.LG
TL;DR: MetaCluster enables high compression of Kolmogorov-Arnold Networks (KANs) by using a meta-learner to map embeddings to coefficient vectors, clustering them via K-means, and replacing per-edge vectors with shared centroids, achieving up to 124× parameter reduction without accuracy loss.
Details
Motivation: KANs replace scalar weights with per-edge vectors of basis coefficients, increasing expressivity but also dramatically increasing parameters and memory usage. There's a need to compress KANs without sacrificing their accuracy advantages.Method: A lightweight meta-learner is trained jointly with the KAN to map low-dimensional embeddings to coefficient vectors, shaping them to lie on a low-dimensional manifold. K-means clustering is then run in coefficient space, replacing per-edge vectors with shared centroids. The meta-learner is discarded, and brief fine-tuning of the centroid codebook recovers any residual accuracy loss.
Result: On MNIST, CIFAR-10, and CIFAR-100 across standard KANs and ConvKANs, MetaCluster achieves up to 80× reduction in parameter storage with no accuracy loss. On high-dimensional equation modeling tasks, it achieves 124.1× parameter reduction without performance impact.
Conclusion: MetaCluster provides an effective framework for compressing KANs by exploiting the vector nature of their parameters, enabling storage of only a small codebook and per-edge indices while maintaining accuracy.
Abstract: Kolmogorov-Arnold Networks (KANs) replace scalar weights with per-edge vectors of basis coefficients, thereby increasing expressivity and accuracy while also resulting in a multiplicative increase in parameters and memory. We propose MetaCluster, a framework that makes KANs highly compressible without sacrificing accuracy. Specifically, a lightweight meta-learner, trained jointly with the KAN, maps low-dimensional embeddings to coefficient vectors, thereby shaping them to lie on a low-dimensional manifold that is amenable to clustering. We then run K-means in coefficient space and replace per-edge vectors with shared centroids. Afterwards, the meta-learner can be discarded, and a brief fine-tuning of the centroid codebook recovers any residual accuracy loss. The resulting model stores only a small codebook and per-edge indices, exploiting the vector nature of KAN parameters to amortize storage across multiple coefficients. On MNIST, CIFAR-10, and CIFAR-100, across standard KANs and ConvKANs using multiple basis functions, MetaCluster achieves a reduction of up to $80\times$ in parameter storage, with no loss in accuracy. Similarly, on high-dimensional equation modeling tasks, MetaCluster achieves a parameter reduction of $124.1\times$, without impacting performance. Code will be released upon publication.
[1032] Solving General-Utility Markov Decision Processes in the Single-Trial Regime with Online Planning
Pedro P. Santos, Alberto Sardinha, Francisco S. Melo
Main category: cs.LG
TL;DR: First approach for solving infinite-horizon discounted general-utility MDPs in single-trial regime using policy optimization and Monte-Carlo tree search
Details
Motivation: Address the challenge of solving general-utility Markov decision processes when performance is evaluated based on a single trajectory rather than expected performance over multiple trialsMethod: 1) Fundamental analysis of policy optimization in single-trial regime, identifying optimal policy classes and computational hardness; 2) Casting problem as equivalent MDP; 3) Leveraging online planning with Monte-Carlo tree search algorithm
Result: Superior performance compared to relevant baselines in experimental evaluations
Conclusion: First successful approach for solving GUMDPs in single-trial regime, combining theoretical analysis with practical Monte-Carlo tree search implementation
Abstract: In this work, we contribute the first approach to solve infinite-horizon discounted general-utility Markov decision processes (GUMDPs) in the single-trial regime, i.e., when the agent’s performance is evaluated based on a single trajectory. First, we provide some fundamental results regarding policy optimization in the single-trial regime, investigating which class of policies suffices for optimality, casting our problem as a particular MDP that is equivalent to our original problem, as well as studying the computational hardness of policy optimization in the single-trial regime. Second, we show how we can leverage online planning techniques, in particular a Monte-Carlo tree search algorithm, to solve GUMDPs in the single-trial regime. Third, we provide experimental results showcasing the superior performance of our approach in comparison to relevant baselines.
[1033] Test-Time Iterative Error Correction for Efficient Diffusion Models
Yunshan Zhong, Weiqi Yan, Yuxin Zhang
Main category: cs.LG
TL;DR: IEC is a test-time error correction method that reduces exponential error accumulation in efficient diffusion models by iteratively refining outputs without retraining.
Details
Motivation: Efficient diffusion models for resource-constrained devices suffer from approximation errors that accumulate exponentially across timesteps, degrading generation quality. These errors are hard to fix after deployment since model modification is typically infeasible.Method: Proposes Iterative Error Correction (IEC), a test-time method that mitigates inference-time errors by iteratively refining the model’s output. IEC is theoretically proven to reduce error propagation from exponential to linear growth without requiring retraining or architectural changes.
Result: Extensive experiments show IEC consistently improves generation quality across various datasets, efficiency techniques, and model architectures, establishing it as a practical and generalizable solution for test-time enhancement of efficient diffusion models.
Conclusion: IEC provides a flexible trade-off between performance and efficiency that can seamlessly integrate into existing diffusion models’ inference processes, offering a practical solution for enhancing efficient diffusion models at test time.
Abstract: With the growing demand for high-quality image generation on resource-constrained devices, efficient diffusion models have received increasing attention. However, such models suffer from approximation errors introduced by efficiency techniques, which significantly degrade generation quality. Once deployed, these errors are difficult to correct, as modifying the model is typically infeasible in deployment environments. Through an analysis of error propagation across diffusion timesteps, we reveal that these approximation errors can accumulate exponentially, severely impairing output quality. Motivated by this insight, we propose Iterative Error Correction (IEC), a novel test-time method that mitigates inference-time errors by iteratively refining the model’s output. IEC is theoretically proven to reduce error propagation from exponential to linear growth, without requiring any retraining or architectural changes. IEC can seamlessly integrate into the inference process of existing diffusion models, enabling a flexible trade-off between performance and efficiency. Extensive experiments show that IEC consistently improves generation quality across various datasets, efficiency techniques, and model architectures, establishing it as a practical and generalizable solution for test-time enhancement of efficient diffusion models. The code is available in https://github.com/zysxmu/IEC.
[1034] Meta-reinforcement learning with minimum attention
Shashank Gupta, Pilhwa Lee
Main category: cs.LG
TL;DR: Minimum attention control applied to reinforcement learning for fast adaptation and energy efficiency in high-dimensional nonlinear dynamics.
Details
Motivation: To apply minimum attention control principles from biological motor learning to reinforcement learning for improved adaptation, stabilization, and energy efficiency in complex dynamic systems.Method: Combines minimum attention regularization in RL rewards with model-based meta-learning. Uses ensemble-based model learning and gradient-based meta-policy learning alternately for high-dimensional nonlinear dynamics.
Result: Outperforms state-of-the-art model-free and model-based RL algorithms in fast adaptation with few shots, reduces variance from model/environment perturbations, and improves energy efficiency.
Conclusion: Minimum attention control principles effectively enhance RL for complex dynamic systems, providing benefits in adaptation speed, stability, and energy efficiency through meta-learning integration.
Abstract: Minimum attention applies the least action principle in the changes of control concerning state and time, first proposed by Brockett. The involved regularization is highly relevant in emulating biological control, such as motor learning. We apply minimum attention in reinforcement learning (RL) as part of the rewards and investigate its connection to meta-learning and stabilization. Specifically, model-based meta-learning with minimum attention is explored in high-dimensional nonlinear dynamics. Ensemble-based model learning and gradient-based meta-policy learning are alternately performed. Empirically, the minimum attention does show outperforming competence in comparison to the state-of-the-art algorithms of model-free and model-based RL, i.e., fast adaptation in few shots and variance reduction from the perturbations of the model and environment. Furthermore, the minimum attention demonstrates an improvement in energy efficiency.
[1035] Open-Set Domain Adaptation Under Background Distribution Shift: Challenges and A Provably Efficient Solution
Shravan Chaudhari, Yoav Wald, Suchi Saria
Main category: cs.LG
TL;DR: CoLOR is a method for open-set recognition that guarantees performance even when the background distribution of known classes shifts, outperforming existing methods under distribution shift.
Details
Motivation: Real-world ML deployment faces challenges with data shifts, including new classes emerging (open-set recognition) and distribution changes of known categories. Current open-set recognition guarantees assume fixed background distributions, but this paper addresses the more challenging case where background distributions shift.Method: Develops CoLOR method with theoretical guarantees for open-set recognition under background shift. Assumes novel class is separable from non-novel classes. Provides techniques to make CoLOR scalable and robust. Performs comprehensive empirical evaluations on image and text data.
Result: CoLOR significantly outperforms existing open-set recognition methods under background shift. Provides new insights into how factors like novel class size influence performance, an aspect not extensively explored in prior work.
Conclusion: CoLOR provides a theoretically-grounded solution for open-set recognition under challenging background distribution shifts, with practical scalability and robustness improvements over existing methods.
Abstract: As we deploy machine learning systems in the real world, a core challenge is to maintain a model that is performant even as the data shifts. Such shifts can take many forms: new classes may emerge that were absent during training, a problem known as open-set recognition, and the distribution of known categories may change. Guarantees on open-set recognition are mostly derived under the assumption that the distribution of known classes, which we call the background distribution, is fixed. In this paper we develop CoLOR, a method that is guaranteed to solve open-set recognition even in the challenging case where the background distribution shifts. We prove that the method works under benign assumptions that the novel class is separable from the non-novel classes, and provide theoretical guarantees that it outperforms a representative baseline in a simplified overparameterized setting. We develop techniques to make CoLOR scalable and robust, and perform comprehensive empirical evaluations on image and text data. The results show that CoLOR significantly outperforms existing open-set recognition methods under background shift. Moreover, we provide new insights into how factors such as the size of the novel class influences performance, an aspect that has not been extensively explored in prior work.
[1036] Out of the Shadows: Exploring a Latent Space for Neural Network Verification
Lukas Koller, Tobias Ladner, Matthias Althoff
Main category: cs.LG
TL;DR: A novel neural network verification approach using specification-driven input refinement with projection-based set representations (zonotopes) to reduce conservatism in formal verification.
Details
Motivation: Neural networks are sensitive to small input changes, making formal verification crucial for safety-critical applications. Current verification methods often produce inconclusive results due to conservatism in output enclosures.Method: Proposes specification-driven input refinement that iteratively encloses the preimage of unsafe outputs using projection-based set representations (zonotopes). Uses a latent space to transfer constraints between input and output spaces, enabling efficient GPU-accelerated matrix operations.
Result: Developed an efficient verification tool that significantly reduces subproblems in branch-and-bound procedures. Achieves competitive performance compared to top-ranking tools in the international neural network verification competition.
Conclusion: The approach effectively addresses conservatism in neural network verification through input refinement using projection-based set representations, enabling efficient GPU-accelerated verification with competitive performance.
Abstract: Neural networks are ubiquitous. However, they are often sensitive to small input changes. Hence, to prevent unexpected behavior in safety-critical applications, their formal verification – a notoriously hard problem – is necessary. Many state-of-the-art verification algorithms use reachability analysis or abstract interpretation to enclose the set of possible outputs of a neural network. Often, the verification is inconclusive due to the conservatism of the enclosure. To address this problem, we propose a novel specification-driven input refinement procedure, i.e., we iteratively enclose the preimage of a neural network for all unsafe outputs to reduce the set of possible inputs to only enclose the unsafe ones. For that, we transfer output specifications to the input space by exploiting a latent space, which is an artifact of the propagation of a projection-based set representation through a neural network. A projection-based set representation, e.g., a zonotope, is a “shadow” of a higher-dimensional set – a latent space – that does not change during a set propagation through a neural network. Hence, the input set and the output enclosure are “shadows” of the same latent space that we can use to transfer constraints. We present an efficient verification tool for neural networks that uses our iterative refinement to significantly reduce the number of subproblems in a branch-and-bound procedure. Using zonotopes as a set representation, unlike many other state-of-the-art approaches, our approach can be realized by only using matrix operations, which enables a significant speed-up through efficient GPU acceleration. We demonstrate that our tool achieves competitive performance compared to the top-ranking tools of the international neural network verification competition.
[1037] Interpretable Discovery of One-parameter Subgroups: A Modular Framework for Elliptical, Hyperbolic, and Parabolic Symmetries
Pavan Karjol, Vivek V Kashyap, Rohan Kashyap, Prathosh A P
Main category: cs.LG
TL;DR: A framework for discovering unknown one-parameter symmetry subgroups from data while learning functional mappings, with guaranteed invariance/equivariance by construction.
Details
Motivation: Traditional geometric deep learning assumes known symmetries, but real-world data often has unknown or partially known symmetries. The paper aims to discover the underlying continuous symmetry subgroups directly from data rather than assuming them.Method: A modular, data-driven framework that: 1) assumes one of three geometric regimes (elliptical, hyperbolic, parabolic), 2) instantiates corresponding symmetry discovery architecture with invariant/equivariant layers structured by Lie algebra, 3) learns generator parameters end-to-end from data, guaranteeing invariance/equivariance by construction.
Result: Accurate subgroup recovery and strong predictive performance on synthetic and real-world tasks including moment of inertia prediction, double-pendulum dynamics, and high-energy Top Quark Tagging across both compact and non-compact regimes.
Conclusion: The framework successfully discovers unknown symmetry subgroups from data while maintaining formal guarantees, applicable to various matrix Lie groups including SO(n), SL(n), and Lorentz group, bridging geometric deep learning with symmetry discovery.
Abstract: We propose a modular, data-driven framework for jointly learning unknown functional mappings and discovering the underlying one-parameter symmetry subgroup governing the data. Unlike conventional geometric deep learning methods that assume known symmetries, our approach identifies the relevant continuous subgroup directly from data. We consider the broad class of one-parameter subgroups, which admit a canonical geometric classification into three regimes: elliptical, hyperbolic, and parabolic. Given an assumed regime, our framework instantiates a corresponding symmetry discovery architecture with invariant and equivariant representation layers structured according to the Lie algebra of the subgroup, and learns the exact generator parameters end-to-end from data. This yields models whose invariance or equivariance is guaranteed by construction and admits formal proofs, enabling symmetry to be explicitly traced to identifiable components of the architecture. The approach is applicable to one-parameter subgroups of a wide range of matrix Lie groups, including $SO(n)$, $SL(n)$, and the Lorentz group. Experiments on synthetic and real-world systems, including moment of inertia prediction, double-pendulum dynamics, and high-energy \textit{Top Quark Tagging}, demonstrate accurate subgroup recovery and strong predictive performance across both compact and non-compact regimes.
[1038] Automatic and Structure-Aware Sparsification of Hybrid Neural ODEs
Bob Junyi Zou, Lu Tian
Main category: cs.LG
TL;DR: Hybrid neural ODEs combine mechanistic models with neural networks for healthcare applications, but suffer from training inefficiency and overfitting due to excessive latent states. Proposed method uses automatic state selection and structure optimization with graph modifications and regularization to sparsify models while retaining mechanistic plausibility.
Details
Motivation: Hybrid neural ODEs offer strong inductive bias and flexibility for data-scarce healthcare settings, but their practical effectiveness is limited by training inefficiency and over-fitting caused by excessive latent states and interactions from mechanistic models.Method: Proposes a hybrid pipeline combining domain-informed graph modifications with data-driven regularization for automatic state selection and structure optimization in mechanistic neural ODEs. The approach sparsifies models to improve predictive performance and stability while retaining mechanistic plausibility.
Result: Experiments on synthetic and real-world data show improved predictive performance and robustness with desired sparsity, establishing an effective solution for hybrid model reduction in healthcare applications.
Conclusion: The proposed method successfully addresses training inefficiency and overfitting in hybrid neural ODEs through automatic state selection and structure optimization, making hybrid models more practical for healthcare applications while maintaining mechanistic plausibility.
Abstract: Hybrid neural ordinary differential equations (neural ODEs) integrate mechanistic models with neural ODEs, offering strong inductive bias and flexibility, and are particularly advantageous in data-scarce healthcare settings. However, excessive latent states and interactions from mechanistic models can lead to training inefficiency and over-fitting, limiting practical effectiveness of hybrid neural ODEs. In response, we propose a new hybrid pipeline for automatic state selection and structure optimization in mechanistic neural ODEs, combining domain-informed graph modifications with data-driven regularization to sparsify the model for improving predictive performance and stability while retaining mechanistic plausibility. Experiments on synthetic and real-world data show improved predictive performance and robustness with desired sparsity, establishing an effective solution for hybrid model reduction in healthcare applications.
[1039] ASSESS: A Semantic and Structural Evaluation Framework for Statement Similarity
Xiaoyang Liu, Tao Zhu, Zineng Dong, Yuntian Liu, Qingfeng Guo, Zhaoxuan Liu, Yu Chen, Tao Luo
Main category: cs.LG
TL;DR: ASSESS introduces a semantic and structural evaluation framework for formal statement similarity using operator trees and TransTED similarity metric, validated on the EPLA benchmark.
Details
Motivation: Existing autoformalization evaluation metrics fail to balance semantic and structural information - string-based methods neglect semantics while proof-based approaches lack graded similarity when proofs fail.Method: Transforms formal statements into operator trees and computes real-valued similarity using novel TransTED (Transformation Tree Edit Distance) Similarity metric that incorporates semantic transformations.
Result: TransTED Similarity surpasses existing methods on the EPLA benchmark, achieving state-of-the-art accuracy and Kappa score.
Conclusion: ASSESS provides an effective framework for evaluating formal translation quality by capturing both syntactic structure and semantic information through operator trees and TransTED similarity.
Abstract: Despite significant strides in statement autoformalization, a critical gap remains in the development of automated evaluation metrics capable of assessing formal translation quality. Existing metrics often fail to balance semantic and structural information: string-based methods neglect semantics, whereas proof-based approaches offer no graded similarity when proofs fail. To address these issues, we introduce ASSESS (A Semantic and Structural Evaluation Framework for Statement Similarity), which captures syntactic structure by transforming formal statements into operator trees and computes a real-valued similarity score using our novel TransTED (Transformation Tree Edit Distance) Similarity metric by incorporating semantic transformations. For rigorous validation, we present EPLA (Evaluating Provability and Likeness for Autoformalization), a benchmark comprising 1,247 expert-annotated formal statement pairs derived from miniF2F and ProofNet, distinctively labeled for both semantic provability and structural likeness. Experiments on the EPLA benchmark demonstrate that TransTED Similarity surpasses existing methods, achieving state-of-the-art accuracy and Kappa score. The benchmark dataset, code, and detailed experimental results are available at https://github.com/XiaoyangLiu-sjtu/ASSESS.
[1040] Rectified Flows for Fast Multiscale Fluid Flow Modeling
Victor Armegioiu, Yannick Ramic, Siddhartha Mishra
Main category: cs.LG
TL;DR: Rectified-flow surrogate model for fluid dynamics that uses deterministic ODE solving instead of stochastic diffusion, achieving comparable accuracy with far fewer steps (8 vs 128+) through near-straight trajectory learning.
Details
Motivation: Statistical surrogate modeling of fluid flows is challenging due to multiscale dynamics and sensitivity to initial conditions. While conditional diffusion surrogates can be accurate, they require hundreds of stochastic sampling steps, making them computationally expensive.Method: Proposes a rectified-flow surrogate that learns a time-dependent conditional velocity field transporting input-to-output laws along near-straight trajectories. Inference becomes a deterministic ODE solve. Introduces a curvature-aware sampler that uses an EMA straightness proxy to adapt blending and step sizes at inference.
Result: Matches diffusion-class posterior statistics with only 8 ODE steps versus ≥128 for score-based diffusion. Across incompressible and compressible multiscale 2D flows, it matches diffusion baselines in Wasserstein statistics and spectra, preserves fine-scale structure beyond MSE surrogates, and significantly reduces inference cost.
Conclusion: Rectified-flow surrogates offer an efficient alternative to diffusion models for fluid flow prediction, achieving comparable accuracy with dramatically reduced computational cost through deterministic ODE solving and curvature-aware sampling.
Abstract: Statistical surrogate modeling of fluid flows is hard because dynamics are multiscale and highly sensitive to initial conditions. Conditional diffusion surrogates can be accurate, but usually need hundreds of stochastic sampling steps. We propose a rectified-flow surrogate that learns a time-dependent conditional velocity field transporting input-to-output laws along near-straight trajectories. Inference is then a deterministic ODE solve, making each function evaluation more informative: on multiscale 2D benchmarks, we match diffusion-class posterior statistics with only (8) ODE steps versus (\ge 128) for score-based diffusion. Theoretically, we give a law-level analysis for conditional PDE forecasting. We (i) connect one-point Wasserstein field metrics to the (k=1) correlation-marginal perspective in statistical solutions, (ii) derive a one-step error split into a coverage term (high-frequency tail, controlled by structure functions/spectral decay) and a fit term (controlled by the training objective), and (iii) show that rectification-time straightness controls ODE local truncation error, yielding practical step-size/step-count guidance. Motivated by this, we introduce a curvature-aware sampler that uses an EMA straightness proxy to adapt blending and step sizes at inference. Across incompressible and compressible multiscale 2D flows, it matches diffusion baselines in Wasserstein statistics and spectra, preserves fine-scale structure beyond MSE surrogates, and significantly reduces inference cost.
[1041] Functional Critics Are Essential for Actor-Critic: From Off-Policy Stability to Efficient Exploration
Qinxun Bai, Yuxuan Han, Wei Xu, Zhengyuan Zhou
Main category: cs.LG
TL;DR: Functional critics (policy-conditioned value functions) are essential for stabilizing off-policy actor-critic RL, enabling convergent algorithms without restrictive assumptions, and bridging the gap to efficient exploration.
Details
Motivation: The actor-critic framework suffers from the "moving target" problem where the evaluated policy changes continually. While functional critics conceptually address this by including policy representations as input, previous implementations have struggled to compete with standard AC methods.Method: Revisits functional critics within actor-critic framework, identifies two critical aspects: 1) Stabilizes interplay between “deadly triad” and “moving target” through convergent off-policy AC algorithm with linear functional approximation, using target-based TD learning and dynamic behavior policies without full coverage assumptions. 2) Formalizes dual trust-coverage mechanism for principled behavior policy updates and critic re-evaluations. Proposes tailored neural network architecture and minimalist AC algorithm.
Result: Achieves performance competitive with state-of-the-art methods on DeepMind Control Suite without standard implementation heuristics. Provides first-of-their-kind contributions: convergent off-policy AC algorithm without restrictive assumptions and foundational link between functional critics and efficient exploration.
Conclusion: Functional critics are a necessity rather than luxury in actor-critic RL, addressing fundamental stability issues and enabling principled off-policy learning while bridging the gap to efficient exploration through policy-dependent uncertainty modeling.
Abstract: The actor-critic (AC) framework has achieved strong empirical success in off-policy reinforcement learning but suffers from the “moving target” problem, where the evaluated policy changes continually. Functional critics, or policy-conditioned value functions, address this by explicitly including a representation of the policy as input. While conceptually appealing, previous efforts have struggled to remain competitive against standard AC. In this work, we revisit functional critics within the actor-critic framework and identify two critical aspects that render them a necessity rather than a luxury. First, we demonstrate their power in stabilizing the complex interplay between the “deadly triad” and the “moving target”. We provide a convergent off-policy AC algorithm under linear functional approximation that dismantles several longstanding barriers between theory and practice: it utilizes target-based TD learning, accommodates dynamic behavior policies, and operates without the restrictive “full coverage” assumptions. By formalizing a dual trust-coverage mechanism, our framework provides principled guidelines for pursuing sample efficiency-rigorously governing behavior policy updates and critic re-evaluations to maximize off-policy data utility. Second, we uncover a foundational link between functional critics and efficient exploration. We demonstrate that existing model-free approximations of posterior sampling are limited in capturing policy-dependent uncertainty, a gap the functional critic formalism bridges. These results represent, to our knowledge, first-of-their-kind contributions to the RL literature. Practically, we propose a tailored neural network architecture and a minimalist AC algorithm. In preliminary experiments on the DeepMind Control Suite, this implementation achieves performance competitive with state-of-the-art methods without standard implementation heuristics.
[1042] Neural MJD: Neural Non-Stationary Merton Jump Diffusion for Time Series Prediction
Yuanpei Gao, Qi Yan, Yan Leng, Renjie Liao
Main category: cs.LG
TL;DR: Neural MJD combines neural networks with Merton jump diffusion modeling for non-stationary time series prediction, using SDE simulation with time-inhomogeneous diffusion and compound Poisson processes to handle abrupt changes.
Details
Motivation: Deep learning methods for time series prediction have limitations: they are black-box models that cannot explicitly model underlying stochastic processes, which restricts their generalization to non-stationary data with abrupt changes.Method: Proposes Neural MJD, a neural network-based non-stationary Merton jump diffusion model that formulates forecasting as SDE simulation. Uses time-inhomogeneous Itô diffusion for stochastic dynamics and time-inhomogeneous compound Poisson process for jumps. Introduces likelihood truncation (capping jumps in small intervals) with theoretical error bound, and an Euler-Maruyama with restart solver with lower error bound and reduced variance.
Result: Experiments on synthetic and real-world datasets show Neural MJD consistently outperforms state-of-the-art deep learning and statistical learning methods.
Conclusion: Neural MJD successfully combines neural networks with explicit stochastic process modeling to handle non-stationary time series with abrupt changes, providing both theoretical guarantees and empirical performance improvements.
Abstract: While deep learning methods have achieved strong performance in time series prediction, their black-box nature and inability to explicitly model underlying stochastic processes often limit their generalization to non-stationary data, especially in the presence of abrupt changes. In this work, we introduce Neural MJD, a neural network based non-stationary Merton jump diffusion (MJD) model. Our model explicitly formulates forecasting as a stochastic differential equation (SDE) simulation problem, combining a time-inhomogeneous Itô diffusion to capture non-stationary stochastic dynamics with a time-inhomogeneous compound Poisson process to model abrupt jumps. To enable tractable learning, we introduce a likelihood truncation mechanism that caps the number of jumps within small time intervals and provide a theoretical error bound for this approximation. Additionally, we propose an Euler-Maruyama with restart solver, which achieves a provably lower error bound in estimating expected states and reduced variance compared to the standard solver. Experiments on both synthetic and real-world datasets demonstrate that Neural MJD consistently outperforms state-of-the-art deep learning and statistical learning methods.
[1043] Vision Transformer Finetuning Benefits from Non-Smooth Components
Ambroise Odonnat, Laetitia Chapel, Romain Tavenard, Ievgen Redko
Main category: cs.LG
TL;DR: Vision transformers’ plasticity (sensitivity to input changes) rather than smoothness is key for better fine-tuning performance, with attention modules and feedforward layers showing highest plasticity.
Details
Motivation: While transformer smoothness has been studied for generalization and robustness, its role in transfer learning remains poorly understood. The paper aims to analyze vision transformer components' plasticity (ability to adapt outputs to input changes) to provide principled guidance for adaptation.Method: Define plasticity as average rate of change capturing sensitivity to input perturbation (high plasticity = low smoothness). Use theoretical analysis and comprehensive experiments to measure plasticity of different vision transformer components during adaptation.
Result: High plasticity of attention modules and feedforward layers consistently leads to better fine-tuning performance. This challenges the prevailing assumption that smoothness is desirable for transfer learning.
Conclusion: Plasticity provides a novel perspective on transformer functional properties, offering practical guidance to prioritize attention and feedforward layers during adaptation rather than assuming smoothness is always beneficial.
Abstract: The smoothness of the transformer architecture has been extensively studied in the context of generalization, training stability, and adversarial robustness. However, its role in transfer learning remains poorly understood. In this paper, we analyze the ability of vision transformer components to adapt their outputs to changes in inputs, or, in other words, their plasticity. Defined as an average rate of change, it captures the sensitivity to input perturbation; in particular, a high plasticity implies low smoothness. We demonstrate through theoretical analysis and comprehensive experiments that this perspective provides principled guidance in choosing the components to prioritize during adaptation. A key takeaway for practitioners is that the high plasticity of the attention modules and feedforward layers consistently leads to better finetuning performance. Our findings depart from the prevailing assumption that smoothness is desirable, offering a novel perspective on the functional properties of transformers. The code is available at https://github.com/ambroiseodt/vit-plasticity.
[1044] Interpretability and Generalization Bounds for Learning Spatial Physics
Alejandro Francisco Queiruga, Theo Gutman-Solo, Shuai Jiang
Main category: cs.LG
TL;DR: The paper analyzes ML model generalization for scientific problems using numerical analysis, finding function space of data is critical and introducing Green’s function extraction from black-box models.
Details
Motivation: To rigorously quantify ML model accuracy and generalization for scientific applications like parameter discovery in differential equations, addressing concerns about deceptive visual results in scientific ML.Method: Uses numerical analysis techniques to analyze accuracy, convergence rates, and generalization bounds of ML models applied to linear differential equations, examining data quantity, discretization, and function space effects.
Result: Found function space of data is critical for generalization; different model classes show opposing generalization behaviors; Green’s function representations can be extracted from black-box model weights.
Conclusion: Provides theoretical insights into scientific ML generalization, introduces mechanistic interpretability via Green’s function extraction, and proposes new cross-validation techniques for physical systems.
Abstract: While there are many applications of ML to scientific problems that look promising, visuals can be deceiving. Using numerical analysis techniques, we rigorously quantify the accuracy, convergence rates, and generalization bounds of certain ML models applied to linear differential equations for parameter discovery or solution finding. Beyond the quantity and discretization of data, we identify that the function space of the data is critical to the generalization of the model. A similar lack of generalization is empirically demonstrated for commonly used models, including physics-specific techniques. Counterintuitively, we find that different classes of models can exhibit opposing generalization behaviors. Based on our theoretical analysis, we also introduce a new mechanistic interpretability lens on scientific models whereby Green’s function representations can be extracted from the weights of black-box models. Our results inform a new cross-validation technique for measuring generalization in physical systems, which can serve as a benchmark.
[1045] Evolution Strategies at Scale: LLM Fine-Tuning Beyond Reinforcement Learning
Xin Qiu, Yulu Gan, Conor F. Hayes, Qiyao Liang, Yinggan Xu, Roberto Dailey, Elliot Meyerson, Babak Hodjat, Risto Miikkulainen
Main category: cs.LG
TL;DR: ES (evolution strategies) can successfully fine-tune billion-parameter LLMs, outperforming RL methods in multiple aspects including reward tolerance, robustness, and stability.
Details
Motivation: The paper challenges the assumption that evolution strategies don't scale to modern LLM sizes, aiming to demonstrate ES as a viable alternative to dominant RL-based fine-tuning approaches.Method: Applied evolution strategies (ES) to full-parameter fine-tuning of billion-parameter LLMs without dimensionality reduction, comparing against established RL implementations.
Result: ES successfully scaled to billion-parameter models, outperforming RL in tolerance to long-horizon/delayed rewards, robustness across base LLMs, reduced reward hacking susceptibility, and improved training stability.
Conclusion: ES is not just an alternative to RL but a fundamentally different backpropagation-free post-training paradigm that opens new directions for LLM fine-tuning beyond current RL-based approaches.
Abstract: Fine-tuning large language models (LLMs) for downstream tasks is an essential stage of modern AI deployment. Reinforcement learning (RL) has emerged as the dominant fine-tuning paradigm, underpinning many state-of-the-art LLMs. In contrast, evolution strategies (ES) has largely been overlooked due to the widespread belief that it does not scale to modern model sizes. This paper overturns this assumption by demonstrating the first successful application of ES to full-parameter fine-tuning of LLMs at the billion-parameter scale, without dimensionality reduction. ES can indeed search over extremely high-dimensional parameter spaces and outperform established RL implementations across multiple axes, including improved tolerance to long-horizon and delayed rewards, robustness across diverse base LLMs, reduced susceptibility to reward hacking, and improved training stability. These findings suggest that ES is not merely a viable alternative to RL, but a fundamentally different and powerful backpropagation-free post-training paradigm that opens a new direction for LLM fine-tuning beyond current RL-based approaches. The source codes are provided at: https://github.com/VsonicV/es-fine-tuning-paper.
[1046] Predicting Graph Structure via Adapted Flux Balance Analysis
Sevvandi Kandanaarachchi, Ziqi Xu, Stefan Westerlund, Conrad Sanderson
Main category: cs.LG
TL;DR: Proposes a graph time series prediction method combining time series forecasting with adapted flux balance analysis (FBA) to handle dynamic graphs with changing vertices.
Details
Motivation: Existing graph prediction methods assume static vertices between consecutive graphs, which limits their applicability to real-world dynamic networks where vertices can change over time.Method: Adapts flux balance analysis (FBA) from biochemistry to incorporate constraints for growing graphs, combined with time series prediction methods to forecast future graph structures.
Result: Empirical evaluations on synthetic datasets (Preferential Attachment model) and real datasets (UCI Message, HePH, Facebook, Bitcoin) demonstrate the efficacy of the proposed approach.
Conclusion: The proposed method effectively addresses limitations of existing graph prediction approaches by handling dynamic graphs with changing vertices through adapted FBA and time series prediction.
Abstract: Many dynamic processes such as telecommunication and transport networks can be described through discrete time series of graphs. Modelling the dynamics of such time series enables prediction of graph structure at future time steps, which can be used in applications such as detection of anomalies. Existing approaches for graph prediction have limitations such as assuming that the vertices do not to change between consecutive graphs. To address this, we propose to exploit time series prediction methods in combination with an adapted form of flux balance analysis (FBA), a linear programming method originating from biochemistry. FBA is adapted to incorporate various constraints applicable to the scenario of growing graphs. Empirical evaluations on synthetic datasets (constructed via Preferential Attachment model) and real datasets (UCI Message, HePH, Facebook, Bitcoin) demonstrate the efficacy of the proposed approach.
[1047] Specialization after Generalization: Towards Understanding Test-Time Training in Foundation Models
Jonas Hübotter, Patrik Wolf, Alexander Shevchenko, Dennis Jüni, Andreas Krause, Gil Kur
Main category: cs.LG
TL;DR: Test-time training (TTT) improves performance by allowing foundation models to specialize on test tasks, addressing global underparameterization through post-generalization specialization.
Details
Motivation: Existing explanations for test-time training effectiveness focus on out-of-distribution adaptation or privileged data, but these don't explain why TTT works with in-distribution data for large foundation models. The authors propose that foundation models remain globally underparameterized, and TTT enables specialization after generalization.Method: The authors propose a theoretical model under the linear representation hypothesis showing TTT achieves smaller in-distribution test error than global training. They empirically validate assumptions using sparse autoencoder training on ImageNet, and perform scaling studies across image and language tasks to identify regimes where specialization is most effective.
Result: The paper shows that semantically related data points are explained by only a few shared concepts, confirming the model’s key assumptions. Scaling studies across image and language tasks identify regimes where specialization through TTT is most effective.
Conclusion: TTT works by allowing foundation models to specialize on test tasks after generalization, addressing global underparameterization. This provides a new explanation for TTT effectiveness that applies to in-distribution data and large foundation models.
Abstract: Recent empirical studies have explored the idea of continuing to train a model at test-time for a given task, known as test-time training (TTT), and have found it to yield significant performance improvements. However, there is limited understanding of why and when TTT is effective. Earlier explanations mostly focused on the observation that TTT may help when applied to out-of-distribution adaptation or used with privileged data. However, the growing scale of foundation models with most test data being in-distribution questions these explanations. We instead posit that foundation models remain globally underparameterized, with TTT providing a mechanism for specialization after generalization, focusing capacity on concepts relevant to the test task. Specifically, under the linear representation hypothesis, we propose a model in which TTT achieves a substantially smaller in-distribution test error than global training. We empirically validate our model’s key assumptions by training a sparse autoencoder on ImageNet, showing that semantically related data points are explained by only a few shared concepts. Finally, we perform scaling studies across image and language tasks that confirm the practical implications of our model, identifying the regimes where specialization is most effective.
[1048] Einstein Fields: A Neural Perspective To Computational General Relativity
Sandeep Suresh Cranganore, Andrei Bodnar, Arturs Berzins, Johannes Brandstetter
Main category: cs.LG
TL;DR: Einstein Fields is a neural representation that compresses 4D numerical relativity simulations into compact neural network weights, enabling efficient storage and accurate physical quantity derivation via automatic differentiation.
Details
Motivation: Numerical relativity simulations are computationally intensive and generate massive datasets. The authors aim to develop a more efficient representation that can compress these simulations while maintaining accuracy and enabling easy derivation of physical quantities.Method: Proposes Einstein Fields as Neural Tensor Fields that encode spacetime geometry into neural network weights. Uses implicit neural representations to model the metric tensor field of general relativity, with physical quantities derived via automatic differentiation rather than finite differencing.
Result: Achieves up to 4,000-fold storage reduction compared to discrete representations while maintaining 5-7 decimal place accuracy. Differentiation is up to 5 orders of magnitude more accurate than naive finite differencing in single precision. Demonstrated on canonical general relativity test cases.
Conclusion: Einstein Fields offer a promising approach for compressing numerical relativity simulations with significant storage efficiency and derivative accuracy advantages, representing an important step in applying machine learning to numerical relativity.
Abstract: We introduce Einstein Fields, a neural representation designed to compress computationally intensive four-dimensional numerical relativity simulations into compact implicit neural network weights. By modeling the metric, the core tensor field of general relativity, Einstein Fields enable the derivation of physical quantities via automatic differentiation. Unlike conventional neural fields (e.g., signed distance, occupancy, or radiance fields), Einstein Fields fall into the class of Neural Tensor Fields with the key difference that, when encoding the spacetime geometry into neural field representations, dynamics emerge naturally as a byproduct. Our novel implicit approach demonstrates remarkable potential, including continuum modeling of four-dimensional spacetime, mesh-agnosticity, storage efficiency, derivative accuracy, and ease of use. It achieves up to a $4,000$-fold reduction in storage memory compared to discrete representations while retaining a numerical accuracy of five to seven decimal places. Moreover, in single precision, differentiation of the Einstein Fields-parameterized metric tensor is up to five orders of magnitude more accurate compared to naive finite differencing methods. We demonstrate these properties on several canonical test beds of general relativity and numerical relativity simulation data, while also releasing an open-source JAX-based library: \href{https://github.com/AndreiB137/EinFields}{https://github.com/AndreiB137/EinFields}, taking the first steps to studying the potential of machine learning in numerical relativity.
[1049] From SGD to Spectra: A Theory of Neural Network Weight Dynamics
Brian Richard Olsen, Sam Fatehmanesh, Frank Xiao, Adarsh Kumarappan, Anirudh Gajula
Main category: cs.LG
TL;DR: The paper develops a continuous-time SDE framework connecting SGD dynamics to singular-value spectra evolution in neural network weight matrices, explaining the observed ‘bulk+tail’ spectral structure.
Details
Motivation: While deep neural networks have achieved remarkable success, their training dynamics remain theoretically unclear. The paper aims to provide a rigorous mathematical foundation for understanding why deep learning works by connecting microscopic SGD dynamics to macroscopic spectral evolution.Method: Develops a continuous-time, matrix-valued stochastic differential equation (SDE) framework that rigorously connects SGD dynamics to singular-value spectra evolution. Derives exact SDEs showing squared singular values follow Dyson Brownian motion with eigenvalue repulsion, and characterizes stationary distributions as gamma-type densities with power-law tails.
Result: Theoretical predictions show squared singular values follow Dyson Brownian motion with eigenvalue repulsion, and stationary distributions are gamma-type densities with power-law tails. Controlled experiments on transformer and MLP architectures validate theoretical predictions and demonstrate quantitative agreement between SDE-based forecasts and observed spectral evolution.
Conclusion: The paper provides the first theoretical explanation for the empirically observed ‘bulk+tail’ spectral structure in trained networks and establishes a rigorous foundation for understanding deep learning training dynamics through the lens of stochastic processes and spectral analysis.
Abstract: Deep neural networks have revolutionized machine learning, yet their training dynamics remain theoretically unclear-we develop a continuous-time, matrix-valued stochastic differential equation (SDE) framework that rigorously connects the microscopic dynamics of SGD to the macroscopic evolution of singular-value spectra in weight matrices. We derive exact SDEs showing that squared singular values follow Dyson Brownian motion with eigenvalue repulsion, and characterize stationary distributions as gamma-type densities with power-law tails, providing the first theoretical explanation for the empirically observed ‘bulk+tail’ spectral structure in trained networks. Through controlled experiments on transformer and MLP architectures, we validate our theoretical predictions and demonstrate quantitative agreement between SDE-based forecasts and observed spectral evolution, providing a rigorous foundation for understanding why deep learning works.
[1050] DyMixOp: A Neural Operator Designed from a Complex Dynamics Perspective with Local-Global Mixing for Solving PDEs
Pengyu Lai, Yixiao Chen, Dewu Yang, Rui Wang, Feng Wang, Hui Xu
Main category: cs.LG
TL;DR: DyMixOp is a novel neural operator framework for PDEs that projects infinite-dimensional dynamics onto finite-dimensional latent space using dynamics-aware priors and inertial manifold theory, featuring local-global mixing transformations to capture nonlinear interactions while mitigating spectral bias.
Details
Motivation: The primary challenge in using neural networks for PDEs is representing nonlinear dynamical systems that are inherently non-linearizable or require infinite-dimensional spaces for linearization. Existing neural operators struggle with spectral bias and capturing complex nonlinear couplings in turbulent flows.Method: DyMixOp integrates theoretical insights from complex dynamical systems using dynamics-aware priors and inertial manifold theory. It introduces local-global mixing (LGM) transformation that multiplicatively couples local fine-scale features with global spectral information. The framework uses a dynamics-informed architecture with stacked LGM layers, timescale-adaptive gating, and parallel aggregation of intermediate dynamics.
Result: Extensive experiments on seven benchmark PDE systems (1D to 3D, elliptic to hyperbolic types) show state-of-the-art performance on six of them, reducing prediction errors by up to 94.3% in chaotic regimes while maintaining computational efficiency and strong scalability.
Conclusion: DyMixOp provides a physically interpretable and computationally structured foundation for approximating nonlinear PDE dynamics, effectively capturing high-frequency details and complex nonlinear couplings while mitigating spectral bias in neural operators.
Abstract: A primary challenge in using neural networks to approximate nonlinear dynamical systems governed by partial differential equations (PDEs) lies in recasting these systems into a tractable representation particularly when the dynamics are inherently non-linearizable or require infinite-dimensional spaces for linearization. To address this challenge, we introduce DyMixOp, a novel neural operator framework for PDEs that integrates theoretical insights from complex dynamical systems. Grounded in dynamics-aware priors and inertial manifold theory, DyMixOp projects the original infinite-dimensional PDE dynamics onto a finite-dimensional latent space. This reduction preserves both essential linear structures and dominant nonlinear interactions, thereby establishing a physically interpretable and computationally structured foundation. Central to this approach is the local-global mixing (LGM) transformation, a key architectural innovation inspired by the convective nonlinearity in turbulent flows. By multiplicatively coupling local fine-scale features with global spectral information, LGM effectively captures high-frequency details and complex nonlinear couplings while mitigating the spectral bias that plagues many existing neural operators. The framework is further enhanced by a dynamics-informed architecture that stacks multiple LGM layers in a hybrid configuration, incorporating timescale-adaptive gating and parallel aggregation of intermediate dynamics. This design enables robust approximation of general evolutionary dynamics across diverse physical regimes. Extensive experiments on seven benchmark PDE systems spanning 1D to 3D, elliptic to hyperbolic types demonstrate that DyMixOp achieves state-of-the-art performance on six of them, significantly reducing prediction errors (by up to 94.3% in chaotic regimes) while maintaining computational efficiency and strong scalability.
[1051] VAO: Validation-Aligned Optimization for Cross-Task Generative Auto-Bidding
Yiqin Lv, Zhiyu Mou, Miao Xu, Jinghao Chen, Qi Wang, Yixiu Mao, Yun Qu, Rongquan Bai, Chuan Yu, Jian Xu, Bo Zheng, Xiangyang Ji
Main category: cs.LG
TL;DR: VAO (Validation-Aligned Optimization) is a data-sharing method for generative auto-bidding that adaptively reweights cross-task data contributions based on validation performance to mitigate gradient bias from distribution shifts.
Details
Motivation: Generative auto-bidding suffers from data scarcity in small-scale settings with limited advertiser participation. Cross-task data sharing can help but introduces gradient bias due to distribution shifts across different tasks, and existing methods are not applicable to generative auto-bidding.Method: Proposes Validation-Aligned Optimization (VAO), a principled data-sharing method that adaptively reweights cross-task data contributions based on validation performance feedback. VAO aligns training dynamics to prioritize updates that improve generalization on the target task. Also introduces a unified generative autobidding framework that generalizes across multiple tasks using a single model and all available task data.
Result: Extensive experiments on standard auto-bidding benchmarks validate the effectiveness of the approach.
Conclusion: VAO effectively leverages auxiliary data and mitigates gradient bias in generative auto-bidding through validation-aligned optimization of cross-task data sharing.
Abstract: Generative auto-bidding has demonstrated strong performance in online advertising, yet it often suffers from data scarcity in small-scale settings with limited advertiser participation. While cross-task data sharing is a natural remedy to mitigate this issue, naive approaches often introduce gradient bias due to distribution shifts across different tasks, and existing methods are not readily applicable to generative auto-bidding. In this paper, we propose Validation-Aligned Optimization (VAO), a principled data-sharing method that adaptively reweights cross-task data contributions based on validation performance feedback. Notably, VAO aligns training dynamics to prioritize updates that improve generalization on the target task, effectively leveraging auxiliary data and mitigating gradient bias. Building on VAO, we introduce a unified generative autobidding framework that generalizes across multiple tasks using a single model and all available task data. Extensive experiments on standard auto-bidding benchmarks validate the effectiveness of our approach.
[1052] Constraint Learning in Multi-Agent Dynamic Games from Demonstrations of Local Nash Interactions
Zhouyu Zhang, Chih-Yuan Chiu, Glen Chou
Main category: cs.LG
TL;DR: Inverse dynamic game algorithm learns parametric constraints from multi-agent interaction demonstrations using MILP encoding of KKT conditions to recover constraints consistent with local Nash equilibrium.
Details
Motivation: The paper addresses the problem of learning constraints from observed multi-agent interactions, which is important for understanding agent behavior and designing safe motion plans in interactive environments.Method: Develops mixed-integer linear programs (MILP) that encode the Karush-Kuhn-Tucker (KKT) conditions of interacting agents to recover constraints consistent with local Nash stationarity from interaction demonstrations.
Result: The method accurately infers constraints and designs safe interactive motion plans for various constraint classes (both convex and non-convex) from interaction demonstrations of agents with nonlinear dynamics, validated through simulations and hardware experiments.
Conclusion: The proposed inverse dynamic game approach successfully learns parametric constraints from multi-agent interactions with theoretical guarantees and practical applicability in motion planning.
Abstract: We present an inverse dynamic game-based algorithm to learn parametric constraints from a given dataset of local Nash equilibrium interactions between multiple agents. Specifically, we introduce mixed-integer linear programs (MILP) encoding the Karush-Kuhn-Tucker (KKT) conditions of the interacting agents, which recover constraints consistent with the local Nash stationarity of the interaction demonstrations. We establish theoretical guarantees that our method learns inner approximations of the true safe and unsafe sets. We also use the interaction constraints recovered by our method to design motion plans that robustly satisfy the underlying constraints. Across simulations and hardware experiments, our methods accurately inferred constraints and designed safe interactive motion plans for various classes of constraints, both convex and non-convex, from interaction demonstrations of agents with nonlinear dynamics.
[1053] Efficient Graph Knowledge Distillation from GNNs to Kolmogorov–Arnold Networks via Self-Attention Dynamic Sampling
Can Cui, Zilong Fu, Penghe Huang, Yuanyuan Li, Wu Deng, Dongyan Li
Main category: cs.LG
TL;DR: SA-DSD is a self-attention-guided dynamic sampling distillation framework that uses enhanced Kolmogorov-Arnold Networks (KANs) as student models to distill knowledge from graph neural networks, achieving better performance with fewer parameters and faster runtime.
Details
Motivation: GNNs are computationally expensive for edge devices, and existing KD approaches using MLPs as students have limitations due to fixed activations and lack of neighborhood aggregation, which constrains distilled performance.Method: Proposes SA-DSD framework using enhanced Fourier KAN (FR-KAN+) as student with learnable frequency bases and phase shifts. Uses self-attention mechanism to dynamically identify influential nodes, construct adaptive sampling probability matrices, and enforce teacher-student prediction consistency to compensate for lack of neighborhood aggregation.
Result: Outperforms three GNN teachers by 3.05%-3.62% under inductive settings, improves FR-KAN+ by 15.61%, achieves 16.69x parameter reduction, and 55.75% decrease in average runtime per epoch compared to benchmarks on six real-world datasets.
Conclusion: SA-DSD effectively addresses limitations of MLP-based distillation by using enhanced KANs and self-attention guidance, providing a lightweight yet powerful alternative for deploying graph models on resource-constrained devices.
Abstract: Recent success of graph neural networks (GNNs) in modeling complex graph-structured data has fueled interest in deploying them on resource-constrained edge devices. However, their substantial computational and memory demands present ongoing challenges. Knowledge distillation (KD) from GNNs to MLPs offers a lightweight alternative, but MLPs remain limited by fixed activations and the absence of neighborhood aggregation, constraining distilled performance. To tackle these intertwined limitations, we propose SA-DSD, a novel self-attention-guided dynamic sampling distillation framework. To the best of our knowledge, this is the first work to employ an enhanced Kolmogorov-Arnold Network (KAN) as the student model. We improve Fourier KAN (FR-KAN+) with learnable frequency bases, phase shifts, and optimized algorithms, substantially improving nonlinear fitting capability over MLPs while preserving low computational complexity. To explicitly compensate for the absence of neighborhood aggregation that is inherent to both MLPs and KAN-based students, SA-DSD leverages a self-attention mechanism to dynamically identify influential nodes, construct adaptive sampling probability matrices, and enforce teacher-student prediction consistency. Extensive experiments on six real world datasets demonstrate that, under inductive and most of transductive settings, SA-DSD surpasses three GNN teachers by 3.05%-3.62% and improves FR-KAN+ by 15.61%. Moreover, it achieves a 16.69x parameter reduction and a 55.75% decrease in average runtime per epoch compared to key benchmarks.
[1054] Probabilistic bias adjustment of seasonal predictions of Arctic Sea Ice Concentration
Parsa Gooya, Reinel Sospedra-Alfonso
Main category: cs.LG
TL;DR: Probabilistic error correction framework using conditional Variational Autoencoder to improve Arctic sea ice concentration seasonal forecasts by generating large ensembles of adjusted forecasts with better uncertainty quantification.
Details
Motivation: Seasonal Arctic sea ice forecasts from climate models have systematic biases and complex errors. Current deterministic post-processing methods are limited to expensive ensemble members, but decision-making requires proper uncertainty quantification and likelihood assessment of extreme events.Method: Introduces a probabilistic error correction framework based on conditional Variational Autoencoder (cVAE) to map the conditional distribution of observations given biased model predictions, allowing generation of large ensembles of adjusted forecasts.
Result: Adjusted forecasts show better calibration, closer alignment with observational distribution, and smaller errors compared to climatological mean adjusted forecasts, as evaluated using deterministic and probabilistic metrics.
Conclusion: The cVAE-based probabilistic error correction framework effectively improves Arctic sea ice concentration forecasts by generating large ensembles with better uncertainty quantification, addressing limitations of deterministic post-processing methods.
Abstract: Seasonal forecast of Arctic sea ice concentration is key to mitigate the negative impact and assess potential opportunities posed by the rapid decline of sea ice coverage. Seasonal prediction systems based on climate models often show systematic biases and complex spatio-temporal errors that grow with the forecasts. Consequently, operational predictions are routinely bias corrected and calibrated using retrospective forecasts. For predictions of Arctic sea ice concentration, error corrections are mainly based on one-to-one post-processing methods including climatological mean or linear regression correction and, more recently, machine learning. Such deterministic adjustments are confined at best to the limited number of costly-to-run ensemble members of the raw forecast. However, decision-making requires proper quantification of uncertainty and likelihood of events, particularly of extremes. We introduce a probabilistic error correction framework based on a conditional Variational Autoencoder model to map the conditional distribution of observations given the biased model prediction. This method naturally allows for generating large ensembles of adjusted forecasts. We evaluate our model using deterministic and probabilistic metrics and show that the adjusted forecasts are better calibrated, closer to the observational distribution, and have smaller errors than climatological mean adjusted forecasts.
[1055] RefineStat: Efficient Exploration for Probabilistic Program Synthesis
Madhav Kanda, Shubham Ugare, Sasa Misailovic
Main category: cs.LG
TL;DR: RefineStat is a language model framework that enforces semantic constraints and performs diagnostic-aware refinement to generate statistically reliable probabilistic programs from smaller language models.
Details
Motivation: Probabilistic programming involves navigating complex search spaces with strict constraints, and small language models often produce programs with syntactic and semantic errors when generating probabilistic programs. The authors aim to leverage domain expertise and debugging strategies to improve program synthesis.Method: RefineStat enforces semantic constraints to ensure synthesized programs contain valid distributions and well-formed parameters, then applies diagnostic-aware refinement by resampling prior or likelihood components when reliability checks fail.
Result: The framework produces programs that are both syntactically sound and statistically reliable, often matching or surpassing those from closed-source large language models like OpenAI o3 on multiple probabilistic-programming code-generation tasks.
Conclusion: RefineStat demonstrates that smaller language models can generate high-quality probabilistic programs when guided by domain-specific constraints and refinement strategies, potentially reducing reliance on large closed-source models.
Abstract: Probabilistic programming offers a powerful framework for modeling uncertainty, yet statistical model discovery in this domain entails navigating an immense search space under strict domain-specific constraints. When small language models are tasked with generating probabilistic programs, they frequently produce outputs that suffer from both syntactic and semantic errors, such as flawed inference constructs. Motivated by probabilistic programmers’ domain expertise and debugging strategies, we introduce RefineStat, a language model–driven framework that enforces semantic constraints ensuring synthesized programs contain valid distributions and well-formed parameters, and then applies diagnostic-aware refinement by resampling prior or likelihood components whenever reliability checks fail. We evaluate RefineStat on multiple probabilistic-programming code-generation tasks using smaller language models (SLMs) and find that it produces programs that are both syntactically sound and statistically reliable, often matching or surpassing those from closed-source large language models (e.g., OpenAI o3).
[1056] PAC-Bayesian Reinforcement Learning Trains Generalizable Policies
Abdelkrim Zitouni, Mehdi Hennequin, Juba Agoun, Ryan Horache, Nadia Kabachi, Omar Rivasplata
Main category: cs.LG
TL;DR: Novel PAC-Bayesian generalization bound for RL that accounts for Markov dependencies via mixing time, enabling non-vacuous certificates for off-policy algorithms like SAC, with practical algorithm PB-SAC that optimizes the bound during training.
Details
Motivation: The sequential nature of reinforcement learning data breaks classical independence assumptions, making it challenging to obtain meaningful generalization guarantees. Existing bounds often become vacuous for practical RL algorithms, creating a need for theoretical foundations that account for Markov dependencies.Method: Derives a novel PAC-Bayesian generalization bound that explicitly incorporates the Markov chain’s mixing time to handle sequential dependencies. Develops PB-SAC algorithm that optimizes this bound during training to guide exploration while maintaining performance.
Result: The new bound provides non-vacuous certificates for modern off-policy algorithms like Soft Actor-Critic. Experiments on continuous control tasks show PB-SAC provides meaningful confidence certificates while maintaining competitive performance compared to standard SAC.
Conclusion: The work successfully addresses the challenge of obtaining generalization guarantees for RL by accounting for Markov dependencies through mixing time, providing both theoretical foundations and practical algorithms with confidence certificates.
Abstract: We derive a novel PAC-Bayesian generalization bound for reinforcement learning that explicitly accounts for Markov dependencies in the data, through the chain’s mixing time. This contributes to overcoming challenges in obtaining generalization guarantees for reinforcement learning, where the sequential nature of data breaks the independence assumptions underlying classical bounds. The new bound provides non-vacuous certificates for modern off-policy algorithms such as Soft Actor-Critic. We demonstrate the practical utility of the bound through PB-SAC, a novel algorithm that optimizes the bound during training to guide exploration. Experiments across several continuous control tasks show that the proposed approach provides meaningful confidence certificates while maintaining competitive performance.
[1057] Initialization Schemes for Kolmogorov-Arnold Networks: An Empirical Study
Spyros Rigas, Dhruv Verma, Georgios Alexandridis, Yixuan Wang
Main category: cs.LG
TL;DR: Study of initialization schemes for Kolmogorov-Arnold Networks (KANs), proposing theory-driven approaches inspired by LeCun/Glorot and empirical power-law methods, with comprehensive evaluation showing power-law initialization achieves best performance.
Details
Motivation: KANs are a new neural architecture with trainable activation functions, but their initialization strategies remain largely unexplored despite their importance for training success and performance.Method: Proposed two theory-driven initialization schemes (LeCun-inspired and Glorot-inspired) and an empirical power-law family with tunable exponents. Evaluated through large-scale grid searches on function fitting and forward PDE benchmarks, analyzed training dynamics via Neural Tangent Kernel, and tested on Feynman dataset subset.
Result: Glorot-inspired initialization significantly outperforms baseline in parameter-rich models, while power-law initialization achieves strongest overall performance across tasks and varying architecture sizes.
Conclusion: Proper initialization is crucial for KANs, with power-law initialization emerging as the most effective approach, providing practical guidance for training these novel neural architectures.
Abstract: Kolmogorov-Arnold Networks (KANs) are a recently introduced neural architecture that replace fixed nonlinearities with trainable activation functions, offering enhanced flexibility and interpretability. While KANs have been applied successfully across scientific and machine learning tasks, their initialization strategies remain largely unexplored. In this work, we study initialization schemes for spline-based KANs, proposing two theory-driven approaches inspired by LeCun and Glorot, as well as an empirical power-law family with tunable exponents. Our evaluation combines large-scale grid searches on function fitting and forward PDE benchmarks, an analysis of training dynamics through the lens of the Neural Tangent Kernel, and evaluations on a subset of the Feynman dataset. Our findings indicate that the Glorot-inspired initialization significantly outperforms the baseline in parameter-rich models, while power-law initialization achieves the strongest performance overall, both across tasks and for architectures of varying size. All code and data accompanying this manuscript are publicly available at https://github.com/srigas/KAN_Initialization_Schemes.
[1058] Transformer-based Learning-to-Optimize Approach for Scalable and Generalizable Beamforming
Yubo Zhang, Xiao-Yang Liu, Xiaodong Wang
Main category: cs.LG
TL;DR: Unsupervised deep learning framework using Transformer architecture for downlink beamforming in MU-MISO systems, with curriculum learning, semi-amortized learning, and sliding-window training strategies to improve convergence and performance.
Details
Motivation: To develop a real-time beamforming solution for large-scale MU-MISO channels that can handle dynamic communication environments while avoiding the computational complexity of traditional iterative optimization methods like WMMSE.Method: Multi-layer Transformer architecture that iteratively refines channel and beamformer features via residual connections, trained with three strategies: curriculum learning for better convergence, semi-amortized learning to refine Transformer blocks with gradient ascent, and sliding-window training for optimization stability.
Result: Outperforms existing baselines at low-to-medium SNRs, closely approaches WMMSE performance at high SNRs, and achieves substantially faster inference than iterative and online learning approaches.
Conclusion: The proposed unsupervised deep learning framework provides an effective solution for real-time beamforming with competitive performance and computational efficiency compared to traditional optimization methods.
Abstract: We develop an unsupervised deep learning framework for downlink beamforming in large-scale MU-MISO channels. The model is trained offline, allowing real-time inference through lightweight feedforward computations in dynamic communication environments. Following the learning-to-optimize (L2O) paradigm, a multi-layer Transformer iteratively refines both channel and beamformer features via residual connections. To enhance training, three strategies are introduced: (i) curriculum learning (CL) to improve early-stage convergence and avoid local optima, (ii) semi-amortized learning to refine each Transformer block with a few gradient ascent steps, and (iii) sliding-window training to stabilize optimization by training only a subset of Transformer blocks at a time. Extensive simulations show that the proposed scheme outperforms existing baselines at low-to-medium SNRs and closely approaches WMMSE performance at high SNRs, while achieving substantially faster inference than iterative and online learning approaches.
[1059] Density-Aware Farthest Point Sampling
Paolo Climaco, Jochen Garcke
Main category: cs.LG
TL;DR: DA-FPS is a novel sampling method for selecting training data in limited-label scenarios that minimizes a theoretical error bound based on weighted fill distance, improving regression model performance with fewer labeled samples.
Details
Motivation: When labeled training data is scarce due to computational constraints or high labeling costs, selecting the right training samples from unlabeled data becomes crucial for balancing model performance and efficiency.Method: Proposes Density-Aware Farthest Point Sampling (DA-FPS), a passive model-agnostic sampling method that minimizes a theoretical upper bound for prediction error based on weighted fill distance, which can be estimated from data features alone.
Result: Experiments with two regression models across three datasets show DA-FPS significantly reduces mean absolute prediction error compared to other sampling strategies.
Conclusion: DA-FPS provides an effective approach for selecting training data in label-limited scenarios by theoretically minimizing error bounds and demonstrating practical performance improvements.
Abstract: We focus on training machine learning regression models in scenarios where the availability of labeled training data is limited due to computational constraints or high labeling costs. Thus, selecting suitable training sets from unlabeled data is essential for balancing performance and efficiency. For the selection of the training data, we focus on passive and model-agnostic sampling methods that only consider the data feature representations. We derive an upper bound for the expected prediction error of Lipschitz continuous regression models that linearly depends on the weighted fill distance of the training set: a quantity we can estimate simply by considering the data features. We introduce ‘‘Density-Aware Farthest Point Sampling’’ (DA-FPS), a novel sampling method. We prove that DA-FPS provides approximate minimizers for a data-driven estimation of the weighted fill distance, thereby aiming at minimizing our derived bound. We conduct experiments using two regression models across three datasets. The results demonstrate that DA-FPS significantly reduces the mean absolute prediction error compared to other sampling strategies.
[1060] ActivationReasoning: Logical Reasoning in Latent Activation Spaces
Lukas Helff, Ruben Härle, Wolfgang Stammer, Felix Friedrich, Manuel Brack, Antonia Wüst, Hikaru Shindo, Patrick Schramowski, Kristian Kersting
Main category: cs.LG
TL;DR: ActivationReasoning (AR) embeds logical reasoning into LLM latent spaces using sparse autoencoders to identify concepts, map them to propositions, and apply logical rules for structured reasoning and model control.
Details
Motivation: LLMs generate fluent text but have opaque internal reasoning that's difficult to control. While sparse autoencoders make activations more interpretable, they offer passive features without systematic reasoning or control mechanisms.Method: Three-stage framework: (1) Find latent concept representations via SAEs and organize into dictionary, (2) At inference, detect activating concepts and map to logical propositions, (3) Apply logical rules over propositions to infer higher-order structures, compose concepts, and steer model behavior.
Result: AR scales robustly with reasoning complexity, generalizes to abstract and context-sensitive tasks, and transfers across model backbones. Evaluated on multi-hop reasoning (PrOntoQA), abstraction (Rail2Country), diverse language reasoning (ProverQA), and context-sensitive safety (BeaverTails).
Conclusion: Grounding logical structure in latent activations improves transparency and enables structured reasoning, reliable control, and alignment with desired behaviors, providing a path toward more reliable and auditable AI.
Abstract: Large language models (LLMs) excel at generating fluent text, but their internal reasoning remains opaque and difficult to control. Sparse autoencoders (SAEs) make hidden activations more interpretable by exposing latent features that often align with human concepts. Yet, these features are fragile and passive, offering no mechanism for systematic reasoning or model control. To address this, we introduce ActivationReasoning (AR), a framework that embeds explicit logical reasoning into the latent space of LLMs. It proceeds in three stages: (1) Finding latent representations, first latent concept representations are identified (e.g., via SAEs) and organized into a dictionary; (2) Activating propositions, at inference time AR detects activating concepts and maps them to logical propositions; and (3)Logical reasoning, applying logical rules over these propositions to infer higher-order structures, compose new concepts, and steer model behavior. We evaluate AR on multi-hop reasoning (PrOntoQA), abstraction and robustness to indirect concept cues (Rail2Country), reasoning over natural and diverse language (ProverQA), and context-sensitive safety (BeaverTails). Across all tasks, AR scales robustly with reasoning complexity, generalizes to abstract and context-sensitive tasks, and transfers across model backbones. These results demonstrate that grounding logical structure in latent activations not only improves transparency but also enables structured reasoning, reliable control, and alignment with desired behaviors, providing a path toward more reliable and auditable AI.
[1061] CR-Net: Scaling Parameter-Efficient Training with Cross-Layer Low-Rank Structure
Boao Kong, Junzhu Liang, Yuxi Liu, Renjia Deng, Kun Yuan
Main category: cs.LG
TL;DR: CR-Net is a parameter-efficient framework that uses low-rank residual connections to reduce LLM pre-training costs while maintaining performance.
Details
Motivation: Current low-rank methods for efficient LLM pre-training suffer from compromised performance, computational overhead, and limited memory savings. The authors discovered that inter-layer activation residuals have low-rank properties, which could be leveraged for more efficient architectures.Method: Proposes Cross-layer Low-Rank residual Network (CR-Net) with a dual-path architecture that reconstructs layer activations by combining previous-layer outputs with their low-rank differences. Also develops a specialized activation recomputation strategy to reduce memory requirements.
Result: Extensive pre-training experiments across model scales from 60M to 7B parameters show CR-Net consistently outperforms state-of-the-art low-rank frameworks while requiring fewer computational resources and less memory.
Conclusion: CR-Net effectively addresses the limitations of current low-rank methods by leveraging low-rank activation residuals, achieving better performance with reduced computational and memory costs.
Abstract: Low-rank architectures have become increasingly important for efficient large language model (LLM) pre-training, providing substantial reductions in both parameter complexity and memory/computational demands. Despite these advantages, current low-rank methods face three critical shortcomings: (1) compromised model performance, (2) considerable computational overhead, and (3) limited activation memory savings. To address these limitations, we propose Cross-layer Low-Rank residual Network (CR-Net), an innovative parameter-efficient framework inspired by our discovery that inter-layer activation residuals possess low-rank properties. CR-Net implements this insight through a dual-path architecture that efficiently reconstructs layer activations by combining previous-layer outputs with their low-rank differences, thereby maintaining high-rank information with minimal parameters. We further develop a specialized activation recomputation strategy tailored for CR-Net that dramatically reduces memory requirements. Extensive pre-training experiments across model scales from 60M to 7B parameters demonstrate that CR-Net consistently outperforms state-of-the-art low-rank frameworks while requiring fewer computational resources and less memory.
[1062] Revisiting Performance Claims for Chest X-Ray Models Using Clinical Context
Andrew Wang, Jiashuo Zhang, Michael Oberst
Main category: cs.LG
TL;DR: Paper evaluates chest X-ray models using clinical context from discharge summaries to show performance degrades when correlation between prior context and current labels is broken, suggesting models may rely on inference of clinical context rather than pure image analysis.
Details
Motivation: Current chest X-ray models show strong average performance but may not reflect actual utility in heterogeneous clinical settings, potentially masking weaker performance in medically significant scenarios. Need more holistic evaluation using clinical context.Method: Use discharge summaries recorded prior to each CXR to derive “pre-CXR” probability of each label as proxy for existing contextual knowledge. Probe model performance along two dimensions: stratified analysis by pre-CXR probability, and controlling for pre-CXR probability via matching/re-weighting to break correlation between prior context and current labels.
Result: Models tend to have lower performance (AUROC and other metrics) among individuals with higher pre-CXR probability. Performance degrades when correlation is broken between prior context and current CXR label, suggesting model performance may depend in part on inference of pre-CXR clinical context.
Conclusion: Clinical context is crucial for evaluating medical imaging models. Current SOTA models may rely on inference of pre-existing clinical context rather than pure image analysis, highlighting need for more robust evaluation methodologies in healthcare ML.
Abstract: Public datasets of Chest X-Rays (CXRs) have long been a popular benchmark for developing machine learning (ML) computer vision models in healthcare. However, the reported strong average-case performance of these models do not necessarily reflect their actual utility when used in heterogeneous clinical settings, potentially masking weaker performance in medically significant scenarios. In this work we use clinical context to provide a more holistic evaluation of current “state-of-the-art” (SOTA) models for CXR diagnosis. In particular, we use discharge summaries, recorded prior to each CXR, to derive a “pre-CXR” probability of each CXR label, as a proxy for existing contextual knowledge available to clinicians when interpreting CXRs. We use this measure to probe model performance along two dimensions: First, using a stratified analysis, we show that models tend to have lower performance (as measured by AUROC and other metrics) among individuals with higher pre-CXR probability. Second, by controlling for pre-CXR probability via matching and re-weighting, we demonstrate that performance degrades when the correlation is broken between prior context and the current CXR label, suggesting that model performance may depend in part on inference of pre-CXR clinical context.
[1063] GPTOpt: Teaching LLMs to do Interpretable Black-Box Optimization
Jamison Meindl, Yunsheng Tian, Tony Cui, Veronika Thost, Zhang-Wei Hong, Jie Chen, Wojciech Matusik, Mina Konaković Luković
Main category: cs.LG
TL;DR: GPTOpt fine-tunes Llama 3.1 8B on Bayesian optimization data to enable LLMs to perform continuous black-box optimization with explainable decisions and competitive performance.
Details
Motivation: Current LLMs struggle with continuous black-box optimization tasks and maintaining exploration-exploitation balance, despite their broad capabilities. There's a need for sample-efficient, interpretable optimization methods.Method: Fine-tunes Llama 3.1 8B on structured Bayesian optimization data including surrogate model information, creating an explainable framework that produces surrogate model outputs comparable to Gaussian processes while leveraging LLM flexibility.
Result: GPTOpt shows favorable performance compared to traditional optimizers and transformer-based alternatives on various black-box optimization benchmarks, while providing context and insight into model decisions.
Conclusion: GPTOpt successfully equips LLMs with continuous black-box optimization capabilities through fine-tuning on structured BO data, achieving competitive performance with enhanced interpretability.
Abstract: Global optimization of expensive, derivative-free black-box functions demands extreme sample efficiency and decision interpretability. While Large Language Models (LLMs) have shown broad capabilities, even state-of-the-art models remain limited in solving continuous black-box optimization tasks and struggle to maintain exploration-exploitation balance. We introduce GPTOpt, an optimization method that equips LLMs with continuous black-box optimization capabilities by fine-tuning Llama 3.1 8B on structured Bayesian optimization (BO) data, including surrogate model information. This provides an explainable framework calibrated to produce surrogate model outputs comparable to a Gaussian process, while keeping the advantages of flexible LLM-based optimization. On a variety of black-box optimization benchmarks, our model shows favorable performance compared to traditional optimizers and transformer-based alternatives, while providing important context and insight into the model’s decisions.
[1064] d2: Improved Techniques for Training Reasoning Diffusion Language Models
Guanghan Wang, Gilad Turok, Yair Schiff, Marianne Arriola, Volodymyr Kuleshov
Main category: cs.LG
TL;DR: d2 is a reinforcement learning framework for diffusion language models that improves reasoning ability through novel policy gradient algorithms with accurate trajectory likelihood estimation.
Details
Motivation: While diffusion language models have shown competitive text generation performance, their reasoning capabilities need improvement through reinforcement learning, but existing RL methods face challenges with accurate trajectory likelihood estimation for masked DLMs.Method: Introduces d2 framework with two estimators: d2-AnyOrder for exact trajectory likelihood with single model pass using any-order decoding, and d2-StepMerge for DLMs without any-order decoding that trades compute for approximation accuracy in tractable manner.
Result: d2 significantly outperforms widely-used RL baselines on popular DLMs, achieving new SOTA on logical reasoning tasks (Countdown, Sudoku) and math reasoning benchmarks (GSM8K, MATH500).
Conclusion: The d2 framework effectively enhances reasoning capabilities of diffusion language models through novel RL approaches with accurate likelihood estimation, demonstrating strong performance on reasoning tasks.
Abstract: While diffusion language models (DLMs) have achieved competitive performance in text generation, improving their reasoning ability with reinforcement learning remains an active research area. Here, we introduce d2, a reasoning framework tailored for masked DLMs. Central to our framework is a new policy gradient algorithm that relies on accurate estimates of the sampling trajectory likelihoods. Our likelihood estimator, d2-AnyOrder, achieves exact trajectory likelihood with a single model pass for DLMs that support a sampling algorithm called any-order decoding. Through an empirical study of widely used DLMs, we show that any-order decoding is not universally supported in practice. Consequently, for DLMs that do not naturally support any-order decoding, we propose another estimator, d2-StepMerge, which, unlike d2-AnyOrder, only approximates the trajectory likelihood. d2-StepMerge trades off compute for approximation accuracy in an analytically tractable manner. Empirically, d2 significantly outperforms widely-used RL baselines when applied to popular DLMs, and sets a new state-of-the-art performance for DLMs on logical reasoning tasks (Countdown and Sudoku) and math reasoning benchmarks (GSM8K and MATH500). We provide the code along with a blog post on the project page: https://guanghanwang.com/d2
[1065] Twice Sequential Monte Carlo for Tree Search
Yaniv Oren, Joery A. de Vries, Pascal R. van der Vaart, Matthijs T. J. Spaan, Wendelin Böhmer
Main category: cs.LG
TL;DR: TSMCTS improves upon SMC for model-based RL by reducing variance and path degeneracy while maintaining parallelizability, outperforming both SMC and MCTS baselines across discrete and continuous environments.
Details
Motivation: SMC emerged as a promising alternative to MCTS for model-based RL due to better parallelization and GPU acceleration, but suffers from high variance and path degeneracy that limit its scalability with search depth.Method: Introduces Twice Sequential Monte Carlo Tree Search (TSMCTS) which addresses SMC’s limitations by reducing estimator variance and mitigating path degeneracy while retaining SMC’s parallelization advantages.
Result: TSMCTS outperforms SMC baseline and modern MCTS variants as a policy improvement operator across discrete and continuous environments, scales better with sequential compute, and reduces variance and path degeneracy.
Conclusion: TSMCTS provides an effective solution to SMC’s limitations, making it a competitive alternative to MCTS for model-based RL while maintaining the parallelization advantages that make it suitable for GPU acceleration.
Abstract: Model-based reinforcement learning (RL) methods that leverage search are responsible for many milestone breakthroughs in RL. Sequential Monte Carlo (SMC) recently emerged as an alternative to the Monte Carlo Tree Search (MCTS) algorithm which drove these breakthroughs. SMC is easier to parallelize and more suitable to GPU acceleration. However, it also suffers from large variance and path degeneracy which prevent it from scaling well with increased search depth, i.e., increased sequential compute. To address these problems, we introduce Twice Sequential Monte Carlo Tree Search (TSMCTS). Across discrete and continuous environments TSMCTS outperforms the SMC baseline as well as a popular modern version of MCTS as a policy improvement operator, scales favorably with sequential compute, reduces estimator variance and mitigates the effects of path degeneracy while retaining the properties that make SMC natural to parallelize.
[1066] LOTFormer: Doubly-Stochastic Linear Attention via Low-Rank Optimal Transport
Ashkan Shahbazi, Chayne Thrash, Yikun Bai, Keaton Hamm, Navid NaderiAlizadeh, Soheil Kolouri
Main category: cs.LG
TL;DR: LOTFormer introduces a linear-time doubly stochastic attention mechanism using optimal transport theory with learnable pivot measures to achieve efficient, robust attention with balanced token participation.
Details
Motivation: Standard softmax attention scales quadratically with sequence length, limiting long context modeling. Linear attention helps but most attention mechanisms remain row normalized and can over concentrate mass on a few tokens, harming robustness and information flow. Doubly stochastic attention addresses this but existing approaches add significant overhead.Method: LOTFormer uses an optimal transport view of attention as coupling between query and key measures. It enforces low rank transport by conditioning on a learnable pivot measure with small support. Solves two entropic transport problems (queries→pivot and pivot→keys) and composes them into a conditional coupling that is provably doubly stochastic with rank at most r ≪ n, applying to values in O(nr) time without forming full n×n matrix.
Result: Across vision and text benchmarks, LOTFormer delivers strong accuracy-efficiency tradeoffs when plugged into standard backbones including Swin, DeiT, and BERT.
Conclusion: LOTFormer provides an efficient, doubly stochastic attention mechanism that addresses quadratic scaling and token concentration issues while maintaining strong performance across modalities.
Abstract: Transformers have proven highly effective across modalities, but standard softmax attention scales quadratically with sequence length, limiting long context modeling. Linear attention mitigates this by approximating attention with kernel feature maps, yet most attention mechanisms remain row normalized and can over concentrate mass on a few tokens, harming robustness and information flow. Doubly stochastic attention counteracts this by balancing token participation across both rows and columns, but existing approaches often add significant overhead. We propose LOTFormer, a linear time doubly stochastic attention mechanism derived from an optimal transport view of attention as a coupling between query and key measures. LOTFormer enforces a low rank transport plan by conditioning on a learnable pivot measure with small support. We solve two entropic transport problems, queries to pivot and pivot to keys, and compose them into a conditional coupling that is provably doubly stochastic, has rank at most $r \ll n$, and applies to values in $O(nr)$ time without forming the full $n \times n$ matrix. The pivot locations and masses are learned end-to-end. Across vision and text benchmarks, LOTFormer delivers strong accuracy efficiency tradeoffs when plugged into standard backbones including Swin, DeiT, and BERT.
[1067] China Regional 3km Downscaling Based on Residual Corrective Diffusion Model
Honglu Sun, Hao Jing, Zhixiang Dai, Sa Xiao, Wei Xue, Jian Sun, Qifeng Lu
Main category: cs.LG
TL;DR: Diffusion-based statistical downscaling (CorrDiff) applied to weather forecasting for China region, outperforming operational regional model CMA-MESO in accuracy and generating realistic fine-scale details.
Details
Motivation: To efficiently produce high-resolution weather forecasts by applying deep learning-based statistical downscaling methods to global model outputs, addressing the computational challenges of high-resolution numerical weather prediction.Method: Uses CorrDiff diffusion-based downscaling framework with modifications: scales to 40x larger region, includes high-level variables (six pressure levels), adds global residual connection. Applied to 25km global forecasts from CMA-GFS and SFF to generate 3km forecasts for China region.
Result: Downscaled forecasts outperform direct forecasts of CMA-MESO regional model in MAE for target variables. Radar composite reflectivity forecasts show CorrDiff generates fine-scale details leading to more realistic predictions compared to deterministic regression models.
Conclusion: Diffusion-based statistical downscaling is effective for high-resolution weather forecasting, generating realistic fine-scale details while maintaining accuracy advantages over operational regional models.
Abstract: A fundamental challenge in numerical weather prediction is to efficiently produce high-resolution forecasts. A common solution is applying downscaling methods, which include dynamical downscaling and statistical downscaling, to the outputs of global models. This work focuses on statistical downscaling, which establishes statistical relationships between low-resolution and high-resolution historical data using statistical models. Deep learning has emerged as a powerful tool for this task, giving rise to various high-performance super-resolution models, which can be directly applied for downscaling, such as diffusion models and Generative Adversarial Networks. This work relies on a diffusion-based downscaling framework named CorrDiff. In contrast to the original work of CorrDiff, the region considered in this work is nearly 40 times larger, and we not only consider surface variables as in the original work, but also encounter high-level variables (six pressure levels) as target downscaling variables. In addition, a global residual connection is added to improve accuracy. In order to generate the 3km forecasts for the China region, we apply our trained models to the 25km global grid forecasts of CMA-GFS, an operational global model of the China Meteorological Administration (CMA), and SFF, a data-driven deep learning-based weather model developed from Spherical Fourier Neural Operators (SFNO). CMA-MESO, a high-resolution regional model, is chosen as the baseline model. The experimental results demonstrate that the forecasts downscaled by our method generally outperform the direct forecasts of CMA-MESO in terms of MAE for the target variables. Our forecasts of radar composite reflectivity show that CorrDiff, as a generative model, can generate fine-scale details that lead to more realistic predictions compared to the corresponding deterministic regression models.
[1068] Gradient Descent with Large Step Sizes: Chaos and Fractal Convergence Region
Shuang Liang, Guido Montúfar
Main category: cs.LG
TL;DR: Gradient descent in matrix factorization develops fractal structure under large step sizes, with chaotic behavior near critical step sizes where training outcomes become unpredictable and lack implicit biases.
Details
Motivation: To understand the behavior of gradient descent in matrix factorization, particularly how large step sizes affect convergence and create complex, fractal parameter space structures.Method: Analyze gradient descent dynamics in matrix factorization, derive exact critical step size for scalar-vector factorization, examine sensitivity to initialization, study regularization effects, and extend analysis to general matrix factorization with orthogonal initialization.
Result: Large step sizes create fractal parameter space structure; near critical step sizes, selected minimizer depends sensitively on initialization; regularization amplifies this sensitivity; chaotic regime emerges where training outcome is unpredictable with no simple implicit biases.
Conclusion: Near-critical step sizes in gradient descent for matrix factorization induce chaotic behavior with unpredictable outcomes, challenging assumptions about implicit biases like balancedness, minimum norm, or flatness.
Abstract: We examine gradient descent in matrix factorization and show that under large step sizes the parameter space develops a fractal structure. We derive the exact critical step size for convergence in scalar-vector factorization and show that near criticality the selected minimizer depends sensitively on the initialization. Moreover, we show that adding regularization amplifies this sensitivity, generating a fractal boundary between initializations that converge and those that diverge. The analysis extends to general matrix factorization with orthogonal initialization. Our findings reveal that near-critical step sizes induce a chaotic regime of gradient descent where the training outcome is unpredictable and there are no simple implicit biases, such as towards balancedness, minimum norm, or flatness.
[1069] A Review on Single-Problem Multi-Attempt Heuristic Optimization
Judith Echevarrieta, Etor Arza, Aritz Pérez, Josu Ceberio
Main category: cs.LG
TL;DR: Review paper on sequential selection strategies for single-problem multi-attempt heuristic optimization, unifying approaches from algorithm selection, parameter tuning, multi-start, and resource allocation.
Details
Motivation: Practitioners often need to find the best solution for a single specific optimization problem using multiple heuristic attempts with different algorithms/configurations. Current research is fragmented across different topics without a comprehensive review for this specific setting.Method: Provides a focused review that unifies strategies from algorithm selection, parameter tuning, multi-start, and resource allocation using common terminology and framework. Creates a taxonomy to systematically organize and classify these strategies.
Result: A comprehensive review that facilitates identification and development of strategies for single-problem multi-attempt optimization in practice, addressing the fragmentation in existing literature.
Conclusion: The review successfully addresses the gap by providing a unified framework and taxonomy for sequential alternative selection strategies in single-problem multi-attempt heuristic optimization, making the state-of-the-art more accessible to practitioners.
Abstract: In certain real-world optimization scenarios, practitioners are not interested in solving multiple problems but rather in finding the best solution to a single, specific problem. When the computational budget is large relative to the cost of evaluating a candidate solution, multiple heuristic alternatives can be tried to solve the same given problem, each possibly with a different algorithm, parameter configuration, initialization, or stopping criterion. In this practically relevant setting, the sequential selection of which alternative to try next is crucial for efficiently identifying the best possible solution across multiple attempts. However, suitable sequential alternative selection strategies have traditionally been studied separately across different research topics and have not been the exclusive focus of any existing review. As a result, the state-of-the-art remains fragmented for practitioners interested in this setting, with surveys either covering only subsets of relevant strategies or including approaches that rely on assumptions that are not feasible for the single-problem case. This work addresses the identified gap by providing a focused review of single-problem multi-attempt heuristic optimization. It brings together suitable strategies for this setting that have been studied separately through algorithm selection, parameter tuning, multi-start, and resource allocation. These strategies are described using a unified terminology within a common framework, which supports the construction of a taxonomy for systematically organizing and classifying them. The resulting comprehensive review facilitates both the identification and the development of strategies for the single-problem multi-attempt setting in practice.
[1070] Investigating Data Pruning for Pretraining Biological Foundation Models at Scale
Yifan Wu, Jiyue Jiang, Xichen Ye, Yiqi Wang, Chang Zhou, Yitao Xu, Jiayang Chen, He Hu, Weizhong Zhang, Cheng Jin, Jiao Yuan, Yu Li
Main category: cs.LG
TL;DR: Proposes influence-guided data pruning framework for biological foundation models to reduce computational costs by selecting important training samples, achieving strong performance with extreme pruning rates over 99%.
Details
Motivation: Biological foundation models require massive datasets and parameters, leading to prohibitive computational costs and accessibility barriers for academic labs. Need efficient methods to reduce pretraining data while maintaining performance.Method: Post-hoc influence-guided data pruning framework with subset-based self-influence formulation for efficient sample importance estimation. Two selection strategies: Top-k Influence (Top I) and Coverage-Centric Influence (CCI). Validated on RNA-FM and ESM-C models.
Result: Framework outperforms random selection baselines under extreme pruning rates over 99%. Coreset outperforms random subsets 10x larger in both RNA and protein settings, revealing substantial dataset redundancy.
Conclusion: Influence-guided data pruning can substantially reduce computational costs of BioFM pretraining, enabling more efficient, accessible, and sustainable biological AI research.
Abstract: Biological foundation models (BioFMs), pretrained on large-scale biological sequences, have recently shown strong potential in providing meaningful representations for diverse downstream bioinformatics tasks. However, such models often rely on millions to billions of training sequences and billions of parameters, resulting in prohibitive computational costs and significant barriers to reproducibility and accessibility, particularly for academic labs. To address these challenges, we investigate the feasibility of data pruning for BioFM pretraining and propose a post-hoc influence-guided data pruning framework tailored to biological domains. Our approach introduces a subset-based self-influence formulation that enables efficient estimation of sample importance at low computational cost, and builds upon it two simple yet effective selection strategies, namely Top-k Influence (Top I) and Coverage-Centric Influence (CCI). We empirically validate our method on two representative BioFMs, RNA-FM and ESM-C. For RNA, our framework consistently outperforms random selection baselines under an extreme pruning rate of over 99 percent, demonstrating its effectiveness. Furthermore, we show the generalizability of our framework on protein-related tasks using ESM-C. In particular, our coreset even outperforms random subsets that are ten times larger in both RNA and protein settings, revealing substantial redundancy in biological sequence datasets. These findings underscore the potential of influence-guided data pruning to substantially reduce the computational cost of BioFM pretraining, paving the way for more efficient, accessible, and sustainable biological AI research.
[1071] GeoGen: A Two-stage Coarse-to-Fine Framework for Fine-grained Synthetic Location-based Social Network Trajectory Generation
Rongchao Xu, Kunlin Cai, Lin Jiang, Zhiqing Hong, Yuan Tian, Guang Wang
Main category: cs.LG
TL;DR: GeoGen is a two-stage framework for generating synthetic LBSN check-in trajectories using diffusion models and transformers to overcome spatial-temporal challenges while preserving privacy.
Details
Motivation: LBSN check-in trajectory data is valuable for applications like POI recommendation and advertising, but high collection costs and privacy concerns limit access to large-scale data. Synthetic data generation offers a solution, but existing methods struggle with the spatially discrete, temporally irregular nature of LBSN trajectories and complex spatio-temporal patterns.Method: Two-stage coarse-to-fine framework: 1) Reconstruct continuous latent movement sequences from original trajectories, then use Sparsity-aware Spatio-temporal Diffusion model (S²TDiff) with efficient denoising network to learn behavioral patterns. 2) Use Coarse2FineNet (Transformer-based Seq2Seq with dynamic context fusion encoder and multi-task hybrid-head decoder) to generate fine-grained trajectories from coarse latent sequences by modeling semantic relevance and behavioral uncertainty.
Result: Extensive experiments on four real-world datasets show GeoGen excels state-of-the-art models in both fidelity and utility evaluation, achieving over 69% and 55% improvements in distance and radius metrics on the FS-TKY dataset.
Conclusion: GeoGen effectively addresses the challenges of generating synthetic LBSN check-in trajectories by combining diffusion models for pattern learning and transformers for fine-grained generation, providing a practical solution for privacy-preserving synthetic trajectory data.
Abstract: Location-Based Social Network (LBSN) check-in trajectory data are important for many practical applications, like POI recommendation, advertising, and pandemic intervention. However, the high collection costs and ever-increasing privacy concerns prevent us from accessing large-scale LBSN trajectory data. The recent advances in synthetic data generation provide us with a new opportunity to achieve this, which utilizes generative AI to generate synthetic data that preserves the characteristics of real data while ensuring privacy protection. However, generating synthetic LBSN check-in trajectories remains challenging due to their spatially discrete, temporally irregular nature and the complex spatio-temporal patterns caused by sparse activities and uncertain human mobility. To address this challenge, we propose GeoGen, a two-stage coarse-to-fine framework for large-scale LBSN check-in trajectory generation. In the first stage, we reconstruct spatially continuous, temporally regular latent movement sequences from the original LBSN check-in trajectories and then design a Sparsity-aware Spatio-temporal Diffusion model (S$^2$TDiff) with an efficient denosing network to learn their underlying behavioral patterns. In the second stage, we design Coarse2FineNet, a Transformer-based Seq2Seq architecture equipped with a dynamic context fusion mechanism in the encoder and a multi-task hybrid-head decoder, which generates fine-grained LBSN trajectories based on coarse-grained latent movement sequences by modeling semantic relevance and behavioral uncertainty. Extensive experiments on four real-world datasets show that GeoGen excels state-of-the-art models for both fidelity and utility evaluation, e.g., it increases over 69% and 55% in distance and radius metrics on the FS-TKY dataset.
[1072] Differentially Private Linear Regression and Synthetic Data Generation with Statistical Guarantees
Shurong Lin, Aleksandra Slavković, Deekshith Reddy Bhoomireddy
Main category: cs.LG
TL;DR: DP linear regression method with valid inference and synthetic data generation for small-to-medium social science datasets
Details
Motivation: Social sciences often have small-to-medium datasets where linear regression is standard, but existing DP methods focus on point estimation without uncertainty quantification and don't support synthetic data generation, which is important for reproducibility studies.Method: Proposes a differentially private linear regression method with bias-corrected estimator and asymptotic confidence intervals under Gaussian DP. Uses a binning-aggregation strategy suitable for small-to-moderate dimensions and includes a synthetic data generation procedure where regression on synthetic data matches the DP regression.
Result: Experiments show the method: (1) improves accuracy over existing methods, (2) provides valid confidence intervals, and (3) produces more reliable synthetic data for downstream ML tasks than current DP synthetic data generation approaches.
Conclusion: The method addresses key limitations in DP linear regression by providing valid inference and supporting synthetic data generation, making it suitable for privacy-aware social science research with small-to-medium continuous datasets.
Abstract: In social sciences, small- to medium-scale datasets are common and linear regression (LR) is canonical. In privacy-aware settings, much work has focused on differentially private (DP) LR, but mostly on point estimation with limited attention to uncertainty quantification. Meanwhile, synthetic data generation (SDG) is increasingly important for reproducibility studies, yet current DP LR methods do not readily support it. Mainstream SDG approaches are either tailored to discretized data, making them less suitable for continuous regression, or rely on deep models that require large datasets, limiting their use for the smaller, continuous data typical in social science. We propose a method for LR with valid inference under Gaussian DP: a DP bias-corrected estimator with asymptotic confidence intervals (CIs) and a general SDG procedure in which regression on the synthetic data matches our DP regression. Our binning-aggregation strategy is effective in small- to moderate-dimensional settings. Experiments show our method (1) improves accuracy over existing methods, (2) provides valid CIs, and (3) produces more reliable synthetic data for downstream ML tasks than current DP SDGs.
[1073] TS-Arena – A Live Forecast Pre-Registration Platform
Marcel Meyer, Sascha Kaltenpoth, Henrik Albers, Kevin Zalipski, Oliver Müller
Main category: cs.LG
TL;DR: TS-Arena is a live forecasting platform that evaluates time series foundation models on future data with strict pre-registration to prevent test-set contamination, shifting evaluation from historical to real-time forecasting.
Details
Motivation: Current evaluation of time series foundation models faces challenges with train-test contamination due to sample overlaps and temporal correlations in historical data, making it difficult to assess true generalization capabilities.Method: TS-Arena uses a modular microservice architecture to harmonize data from different sources and orchestrate containerized model submissions. It enforces a strict pre-registration protocol where models must submit predictions before ground-truth data physically exists, preventing information leakage by design.
Result: One year of operation on energy time series shows established time series foundation models accumulate robust longitudinal scores, while continuous benchmarking allows newcomers to demonstrate immediate competitiveness. The platform provides infrastructure for assessing true generalization capabilities.
Conclusion: TS-Arena offers a rigorous evaluation framework for time series forecasting models that prevents test-set contamination through live forecasting and pre-registration, providing a faster alternative to traditional static competitions.
Abstract: Time Series Foundation Models (TSFMs) are transforming the field of forecasting. However, evaluating them on historical data is increasingly difficult due to the risks of train-test sample overlaps and temporal overlaps between correlated train and test time series. To address this, we introduce TS-Arena, a live forecasting platform that shifts evaluation from the known past to the unknown future. Building on the concept of continuous benchmarking, TS-Arena evaluates models on future data. Crucially, we introduce a strict forecasting pre-registration protocol: models must submit predictions before the ground-truth data physically exists. This makes test-set contamination impossible by design. The platform relies on a modular microservice architecture that harmonizes and structures data from different sources and orchestrates containerized model submissions. By enforcing a strict pre-registration protocol on live data streams, TS-Arena prevents information leakage offers a faster alternative to traditional static, infrequently repeated competitions (e.g. the M-Competitions). First empirical results derived from operating TS-Arena over one year of energy time series demonstrate that established TSFMs accumulate robust longitudinal scores over time, while the continuous nature of the benchmark simultaneously allows newcomers to demonstrate immediate competitiveness. TS-Arena provides the necessary infrastructure to assess the true generalization capabilities of modern forecasting models. The platform and corresponding code are available at https://ts-arena.live/.
[1074] Scalable LinUCB: Low-Rank Design Matrix Updates for Recommenders with Large Action Spaces
Evgenia Shustova, Marina Sheshukova, Sergey Samsonov, Evgeny Frolov
Main category: cs.LG
TL;DR: PSI-LinUCB: A scalable variant of LinUCB using low-rank approximation for efficient bandit learning with O(dr) complexity
Details
Motivation: LinUCB algorithms suffer from high computational and memory costs due to maintaining and updating large inverse covariance matrices, making them impractical for large-scale applications like recommender systems.Method: Represent inverse regularized design matrix as diagonal plus low-rank correction; use rank-1 and batched updates without explicit matrix formation; employ projector-splitting integrator for dynamical low-rank approximation to control memory growth.
Result: Achieves O(dr) average per-step update cost and memory usage for approximation rank r, with O(dr) inference complexity per action evaluation; demonstrates effectiveness on recommender system datasets.
Conclusion: PSI-LinUCB provides a scalable, memory-efficient solution for contextual bandit problems with linear payoffs, enabling practical deployment in large-scale applications like recommender systems.
Abstract: In this paper, we introduce PSI-LinUCB, a scalable variant of LinUCB that enables efficient training, inference, and memory usage by representing the inverse regularized design matrix as a sum of a diagonal matrix and low-rank correction. We derive numerically stable rank-1 and batched updates that maintain the inverse without explicitly forming the matrix. To control memory growth, we employ a projector-splitting integrator for dynamical low-rank approximation, yielding an average per-step update cost and memory usage of $O(dr)$ for approximation rank $r$. The inference complexity of the proposed algorithm is $O(dr)$ per action evaluation. Experiments on recommender system datasets demonstrate the effectiveness of our algorithm.
[1075] Towards Reliable Evaluation of Adversarial Robustness for Spiking Neural Networks
Jihang Wang, Dongcheng Zhao, Ruolin Chen, Qian Zhang, Yi Zeng
Main category: cs.LG
TL;DR: Proposes ASSG framework for more reliable adversarial robustness evaluation in SNNs by addressing gradient vanishing through adaptive surrogate gradients and stable adaptive PGD attacks.
Details
Motivation: Current SNN adversarial robustness evaluation is unreliable due to gradient vanishing from binary spike activations. Surrogate gradient methods exist but their effectiveness under strong attacks is unclear, and robustness may be overestimated.Method: 1) Theoretical analysis of gradient vanishing in surrogate gradients; 2) Adaptive Sharpness Surrogate Gradient (ASSG) that evolves surrogate function shape based on input distribution during attacks; 3) Stable Adaptive Projected Gradient Descent (SA-PGD) with adaptive step size under L∞ constraint for faster convergence with imprecise gradients.
Result: ASSG substantially increases attack success rates across diverse adversarial training schemes, SNN architectures, and neuron models. Reveals current SNN robustness is significantly overestimated, providing more generalized and reliable evaluation.
Conclusion: Proposed framework provides more reliable SNN adversarial robustness evaluation, highlighting need for better adversarial training methods. ASSG and SA-PGD effectively address gradient vanishing and convergence issues in SNN attack evaluation.
Abstract: Spiking Neural Networks (SNNs) utilize spike-based activations to mimic the brain’s energy-efficient information processing. However, the binary and discontinuous nature of spike activations causes vanishing gradients, making adversarial robustness evaluation via gradient descent unreliable. While improved surrogate gradient methods have been proposed, their effectiveness under strong adversarial attacks remains unclear. We propose a more reliable framework for evaluating SNN adversarial robustness. We theoretically analyze the degree of gradient vanishing in surrogate gradients and introduce the Adaptive Sharpness Surrogate Gradient (ASSG), which adaptively evolves the shape of the surrogate function according to the input distribution during attack iterations, thereby enhancing gradient accuracy while mitigating gradient vanishing. In addition, we design an adversarial attack with adaptive step size under the $L_\infty$ constraint-Stable Adaptive Projected Gradient Descent (SA-PGD), achieving faster and more stable convergence under imprecise gradients. Extensive experiments show that our approach substantially increases attack success rates across diverse adversarial training schemes, SNN architectures and neuron models, providing a more generalized and reliable evaluation of SNN adversarial robustness. The experimental results further reveal that the robustness of current SNNs has been significantly overestimated and highlighting the need for more dependable adversarial training methods. The code is released at https://github.com/craree/ASSG-SNNs-Robustness-Evaluation
[1076] Generalised Flow Maps for Few-Step Generative Modelling on Riemannian Manifolds
Oscar Davis, Michael S. Albergo, Nicholas M. Boffi, Michael M. Bronstein, Avishek Joey Bose
Main category: cs.LG
TL;DR: GFM is a new class of few-step generative models that extends Flow Map framework from Euclidean to Riemannian manifolds, enabling efficient geometric data generation with state-of-the-art performance.
Details
Motivation: Current geometric generative models on Riemannian manifolds (like diffusion and flow-matching) are computationally expensive at inference, requiring many steps of complex numerical simulation. There's a need for efficient few-step generative models for geometric data in domains like protein generation, computational chemistry, and geospatial data.Method: Proposes Generalised Flow Maps (GFM) that generalize Flow Map framework to arbitrary Riemannian manifolds. Instantiates GFMs with three self-distillation-based training methods: Generalised Lagrangian Flow Maps, Generalised Eulerian Flow Maps, and Generalised Progressive Flow Maps. Theoretically shows GFMs unify and elevate existing Euclidean few-step generative models (consistency models, shortcut models, meanflows) to Riemannian setting.
Result: Benchmarked GFMs against other geometric generative models on geometric datasets including geospatial data, RNA torsion angles, and hyperbolic manifolds. Achieved state-of-the-art sample quality for single- and few-step evaluations, and superior or competitive log-likelihoods using implicit probability flow.
Conclusion: GFM provides an efficient framework for few-step generative modeling on Riemannian manifolds, addressing computational bottlenecks in geometric data generation while maintaining high sample quality and likelihood performance.
Abstract: Geometric data and purpose-built generative models on them have become ubiquitous in high-impact deep learning application domains, ranging from protein backbone generation and computational chemistry to geospatial data. Current geometric generative models remain computationally expensive at inference – requiring many steps of complex numerical simulation – as they are derived from dynamical measure transport frameworks such as diffusion and flow-matching on Riemannian manifolds. In this paper, we propose Generalised Flow Maps (GFM), a new class of few-step generative models that generalises the Flow Map framework in Euclidean spaces to arbitrary Riemannian manifolds. We instantiate GFMs with three self-distillation-based training methods: Generalised Lagrangian Flow Maps, Generalised Eulerian Flow Maps, and Generalised Progressive Flow Maps. We theoretically show that GFMs, under specific design decisions, unify and elevate existing Euclidean few-step generative models, such as consistency models, shortcut models, and meanflows, to the Riemannian setting. We benchmark GFMs against other geometric generative models on a suite of geometric datasets, including geospatial data, RNA torsion angles, and hyperbolic manifolds, and achieve state-of-the-art sample quality for single- and few-step evaluations, and superior or competitive log-likelihoods using the implicit probability flow.
[1077] Trust Region Masking for Long-Horizon LLM Reinforcement Learning
Yingru Li, Jiacai Liu, Jiawei Xu, Yuxuan Tong, Ziniu Li, Qian Liu, Baoxiang Wang
Main category: cs.LG
TL;DR: Derives tighter trust region bounds for LLM policy gradient methods to address off-policy mismatch in long-horizon tasks, proposing Trust Region Masking for non-vacuous guarantees.
Details
Motivation: Modern LLM-RL pipelines suffer from implementation divergences causing off-policy mismatch, and classical trust region bounds scale poorly (O(T²)) with sequence length, making them vacuous for long-horizon tasks.Method: Derives a family of tighter bounds (Pinsker-Marginal: O(T³/²), Mixed: O(T), Adaptive) based on maximum token-level divergence, then proposes Trust Region Masking to mask entire sequences violating trust region constraints.
Result: Achieves the tightest known guarantees across all divergence regimes, enabling non-vacuous monotonic improvement guarantees for long-horizon LLM-RL tasks.
Conclusion: Addresses critical off-policy mismatch in LLM-RL with novel bounds and Trust Region Masking, providing practical solutions for long-horizon reinforcement learning with language models.
Abstract: Policy gradient methods for Large Language Models optimize a policy $π_θ$ via a surrogate objective computed from samples of a rollout policy $π_{\text{roll}}$. However, modern LLM-RL pipelines suffer from unavoidable implementation divergences – backend discrepancies, Mixture-of-Experts routing discontinuities, and distributed training staleness – causing off-policy mismatch ($π_{\text{roll}} \neq π_θ$) and approximation errors between the surrogate and the true objective. We demonstrate that classical trust region bounds on this error scale as $O(T^2)$ with sequence length $T$, rendering them vacuous for long-horizon tasks. To address this, we derive a family of bounds – both KL-based and TV-based – including a Pinsker-Marginal bound ($O(T^{3/2})$), a Mixed bound ($O(T)$), and an Adaptive bound that strictly generalizes the Pinsker-Marginal bound via per-position importance-ratio decomposition. Taking the minimum over all bounds yields the tightest known guarantee across all divergence regimes. Crucially, all bounds depend on the maximum token-level divergence $D_{\mathrm{KL}}^{\mathrm{tok,max}}$ (or $D_{\mathrm{TV}}^{\mathrm{tok,max}}$), a sequence-level quantity that cannot be controlled by token-independent methods like PPO clipping. We propose Trust Region Masking (TRM), which masks entire sequences violating the trust region, enabling the first non-vacuous monotonic improvement guarantees for long-horizon LLM-RL.
[1078] EVINGCA: Adaptive Graph Clustering with Evolving Neighborhood Statistics
Randolph Wiredu-Aidoo
Main category: cs.LG
TL;DR: EVINGCA is a novel clustering algorithm that uses density-variance-based approach with nearest-neighbor graphs and z-score filtering to handle variable densities and non-convex clusters better than existing methods.
Details
Motivation: Existing clustering methods have limitations: K-Means and Gaussian Mixtures assume convex/Gaussian clusters, while density-based methods like DBSCAN/HDBSCAN struggle with variable densities and moderate dimensionality. There's a need for more flexible clustering that can adapt to cluster-specific structure.Method: EVINGCA uses density-variance-based clustering with nearest-neighbor graphs. It grows clusters incrementally via breadth-first search, filters edges using z-scores of neighbor distances, refines estimates as clusters expand, and includes a propagation phase that propagates denser “skeletons” to sharp decision boundaries in low-contrast regions.
Result: Experiments on 28 diverse datasets show competitive runtime behavior and statistically significant improvement over baseline methods in ARI-based label recovery capacity.
Conclusion: EVINGCA provides a robust clustering approach that better handles variable densities and non-convex structures compared to existing methods, offering improved label recovery while maintaining computational efficiency.
Abstract: Clustering is a fundamental tool for discovering structure in data, yet many existing methods rely on restrictive assumptions. Algorithms such as K-Means and Gaussian Mixtures favor convex or Gaussian clusters, while density-based approaches like DBSCAN and HDBSCAN struggle with variable densities or moderate dimensionality. This paper introduces EVINGCA (Evolving Variance-Informed Nonparametric Graph Construction Algorithm), a density-variance-based clustering method that grows clusters incrementally using breadth-first search on a nearest-neighbor graph. Edges are filtered via z-scores of neighbor distances, with estimates refined as clusters expand, enabling adaptation to cluster-specific structure, and a recovery regime distinct from that of existing alternatives. Over-segmentation is exploited by a propagation phase, which propagates inner, denser “skeletons” out to sharp decision boundaries in low-contrast regions. Experiments on 28 diverse datasets demonstrate competitive runtime behavior and a statistically significant improvement over baseline methods in ARI-based label recovery capacity.
[1079] Tree Training: Accelerating Agentic LLMs Training via Shared Prefix Reuse
Shaojie Wang, Jinghui Wang, Yinghan Cui, Xuxing Chen, Chao Wang, Liang Huang, Xiaojiang Zhang, Junyi Peng, Li Wan, Haotian Zhang, Bin Chen
Main category: cs.LG
TL;DR: Tree Training framework enables efficient training of agentic LLMs on tree-structured token trajectories by eliminating redundant computation through gradient restoration and tree packing.
Details
Motivation: Agentic LLM training involves multi-turn interactions that create tree-structured token trajectories due to concurrent tool use, think-mode, and sub-agents. Existing methods linearize these trees, causing redundant computation in forward/backward passes.Method: Introduces Tree Training with Gradient Restoration for correct gradient aggregation across shared prefixes, allowing each prefix to be computed once. Includes tree-structured data ingestion and Tree Packing for memory-efficient partitioning that preserves prefix reuse.
Result: Achieves 6.2x training speedup for both supervised fine-tuning and model update phases in reinforcement learning on dense and MOE models with real-world agentic trajectories.
Conclusion: Tree Training efficiently handles tree-structured trajectories in agentic LLM training, eliminating redundancy while maintaining mathematical equivalence to independent branch training.
Abstract: Agentic large language model (LLM) training often involves multi-turn interaction trajectories that branch into multiple execution paths due to concurrent tool use, think-mode, sub-agent, context management and other runtime designs. As a result, the token produced by a single task naturally forms a tree-structured token trajectory with shared prefixes, rather than a linear sequence. Existing training pipelines linearize such trajectories and treat each branch independently, leading to substantial redundant computation in both forward and backward passes. To eliminate such redundancy, we introduce Tree Training, an efficient training framework for tree-structured trajectories. Its core component, Gradient Restoration, enables correct gradient aggregation across shared prefixes, allowing each prefix to be computed exactly once while remaining mathematically equivalent to independent training on all branches. To support large trajectory trees in practice, we redesign the training engine to natively ingest tree-structured data and propose Tree Packing, a memory-efficient partitioning strategy that preserves high prefix reuse. Experiments conducted on dense and MOE models of real-world agentic trajectories show 6.2x training speedup for both supervised fine-tuning and the model update phase in reinforcement learning.
[1080] HEEGNet: Hyperbolic Embeddings for EEG
Shanglin Li, Shiwen Chu, Okan Koç, Yi Ding, Qibin Zhao, Motoaki Kawanabe, Ziheng Chen
Main category: cs.LG
TL;DR: HEEGNet: A hybrid hyperbolic network architecture for EEG decoding that captures hierarchical structure in EEG data using hyperbolic embeddings to improve generalization across domains.
Details
Motivation: EEG-based brain-computer interfaces suffer from poor generalization due to distribution shifts across domains (subjects). Current methods use Euclidean embeddings, but EEG data exhibits hierarchical structure that could be better represented in hyperbolic space.Method: Proposes HEEGNet with hybrid Euclidean and hyperbolic encoders, empirically demonstrates EEG hyperbolicity, and uses a novel coarse-to-fine domain adaptation strategy to learn domain-invariant hyperbolic embeddings.
Result: Extensive experiments on multiple public EEG datasets (visual evoked potentials, emotion recognition, intracranial EEG) show state-of-the-art performance.
Conclusion: EEG data exhibits hyperbolicity, and hyperbolic embeddings improve generalization; HEEGNet effectively captures hierarchical structure in EEG for better domain adaptation.
Abstract: Electroencephalography (EEG)-based brain-computer interfaces facilitate direct communication with a computer, enabling promising applications in human-computer interactions. However, their utility is currently limited because EEG decoding often suffers from poor generalization due to distribution shifts across domains (e.g., subjects). Learning robust representations that capture underlying task-relevant information would mitigate these shifts and improve generalization. One promising approach is to exploit the underlying hierarchical structure in EEG, as recent studies suggest that hierarchical cognitive processes, such as visual processing, can be encoded in EEG. While many decoding methods still rely on Euclidean embeddings, recent work has begun exploring hyperbolic geometry for EEG. Hyperbolic spaces, regarded as the continuous analogue of tree structures, provide a natural geometry for representing hierarchical data. In this study, we first empirically demonstrate that EEG data exhibit hyperbolicity and show that hyperbolic embeddings improve generalization. Motivated by these findings, we propose HEEGNet, a hybrid hyperbolic network architecture to capture the hierarchical structure in EEG and learn domain-invariant hyperbolic embeddings. To this end, HEEGNet combines both Euclidean and hyperbolic encoders and employs a novel coarse-to-fine domain adaptation strategy. Extensive experiments on multiple public EEG datasets, covering visual evoked potentials, emotion recognition, and intracranial EEG, demonstrate that HEEGNet achieves state-of-the-art performance. The code is available at https://github.com/fightlesliefigt/HEEGNet
[1081] Peeling Context from Cause for Molecular Property Prediction
Tao Li, Kaiyuan Hou, Tuan Vinh, Monika Raj, Carl Yang
Main category: cs.LG
TL;DR: CLaP is a framework for molecular property prediction that separates causal structure from spurious context in a layerwise manner using multimodal graph representations and produces interpretable atom-level saliency maps.
Details
Motivation: Current deep models for molecular property prediction are often uninterpretable and may rely on spurious correlations rather than causal structure, reducing reliability under distribution shift and harming predictive performance.Method: CLaP performs layerwise separation of causal signal from context using a causal block that splits into causal/non-causal branches, fuses causal evidence across modalities, and progressively removes batch-coupled context to focus on label-relevant structure.
Result: Across four molecular benchmarks, CLaP consistently improves MAE, MSE, and R² over competitive baselines and produces accurate atom-level causal saliency maps that align with chemical intuition.
Conclusion: By peeling context from cause at every layer, CLaP yields molecular predictors that are both accurate and interpretable, providing actionable guidance for targeted molecular design.
Abstract: Deep models are used for molecular property prediction, yet they are often difficult to interpret and may rely on spurious context rather than causal structure, which reduces reliability under distribution shift and harms predictive performance. We introduce CLaP (Causal Layerwise Peeling), a framework that separates causal signal from context in a layerwise manner and integrates diverse graph representations of molecules. At each layer, a causal block performs a soft split into causal and non-causal branches, fuses causal evidence across modalities, and progressively removes batch-coupled context to focus on label-relevant structure, thereby limiting shortcut signals and stabilizing layerwise refinement. Across four molecular benchmarks, CLaP consistently improves MAE, MSE, and $R^2$ over competitive baselines. The model also produces atom-level causal saliency maps that highlight substructures responsible for predictions, providing actionable guidance for targeted molecular edits. Case studies confirm the accuracy of these maps and their alignment with chemical intuition. By peeling context from cause at every layer, the model yields predictors that are both accurate and interpretable for molecular design.
[1082] FMMI: Flow Matching Mutual Information Estimation
Ivan Butakov, Alexander Semenenko, Valeriya Kirova, Alexey Frolov, Ivan Oseledets
Main category: cs.LG
TL;DR: A novel mutual information estimator using normalizing flows to transform between joint and marginal distributions, enabling efficient and precise MI estimation in high dimensions.
Details
Motivation: Existing discriminative MI estimators train classifiers to distinguish between joint and marginal distributions, which can be computationally intensive and may not scale well to high dimensions or handle a wide range of MI values effectively.Method: Instead of training a classifier, the method learns a normalizing flow that transforms one distribution into the other. This approach reframes the discriminative paradigm by directly modeling the transformation between joint and marginal distributions.
Result: The technique produces computationally efficient and precise MI estimates that scale well to high-dimensional settings and work across a wide range of ground-truth MI values.
Conclusion: The normalizing flow-based approach provides a fundamentally different and more effective framework for mutual information estimation compared to traditional discriminative methods.
Abstract: We introduce a novel Mutual Information (MI) estimator that fundamentally reframes the discriminative approach. Instead of training a classifier to discriminate between joint and marginal distributions, we learn a normalizing flow that transforms one into the other. This technique produces a computationally efficient and precise MI estimate that scales well to high dimensions and across a wide range of ground-truth MI values.
[1083] A Review of Online Diffusion Policy RL Algorithms for Scalable Robotic Control
Wonhyeok Choi, Shutong Ding, Minwoo Choi, Jungwan Woo, Kyumin Hwang, Jaeyeul Kim, Ye Shi, Sunghoon Im
Main category: cs.LG
TL;DR: A comprehensive review and empirical analysis of Online Diffusion Policy Reinforcement Learning algorithms for robotic control, proposing a taxonomy of four algorithmic families and evaluating them across multiple dimensions using a unified benchmark.
Details
Motivation: Diffusion policies show promise for robotic control due to their ability to model multimodal action distributions, but their integration with online reinforcement learning remains challenging due to incompatibilities between diffusion model training objectives and standard RL policy improvement mechanisms.Method: Proposes a taxonomy categorizing existing Online DPRL approaches into four families (Action-Gradient, Q-Weighting, Proximity-Based, and BPTT methods), then conducts extensive experiments on a unified NVIDIA Isaac Lab benchmark with 12 diverse robotic tasks, evaluating across five dimensions: task diversity, parallelization capability, diffusion step scalability, cross-embodiment generalization, and environmental robustness.
Result: Identifies fundamental trade-offs in each algorithmic family regarding sample efficiency and scalability, reveals computational and algorithmic bottlenecks limiting practical deployment, and provides concrete guidelines for algorithm selection based on operational constraints.
Conclusion: The paper provides a comprehensive analysis of Online DPRL algorithms, offering insights into their strengths/weaknesses and outlining future research directions to advance toward more general and scalable robotic learning systems.
Abstract: Diffusion policies have emerged as a powerful approach for robotic control, demonstrating superior expressiveness in modeling multimodal action distributions compared to conventional policy networks. However, their integration with online reinforcement learning remains challenging due to fundamental incompatibilities between diffusion model training objectives and standard RL policy improvement mechanisms. This paper presents the first comprehensive review and empirical analysis of current Online Diffusion Policy Reinforcement Learning (Online DPRL) algorithms for scalable robotic control systems. We propose a novel taxonomy that categorizes existing approaches into four distinct families–Action-Gradient, Q-Weighting, Proximity-Based, and Backpropagation Through Time (BPTT) methods–based on their policy improvement mechanisms. Through extensive experiments on a unified NVIDIA Isaac Lab benchmark encompassing 12 diverse robotic tasks, we systematically evaluate representative algorithms across five critical dimensions: task diversity, parallelization capability, diffusion step scalability, cross-embodiment generalization, and environmental robustness. Our analysis identifies key findings regarding the fundamental trade-offs inherent in each algorithmic family, particularly concerning sample efficiency and scalability. Furthermore, we reveal critical computational and algorithmic bottlenecks that currently limit the practical deployment of online DPRL. Based on these findings, we provide concrete guidelines for algorithm selection tailored to specific operational constraints and outline promising future research directions to advance the field toward more general and scalable robotic learning systems.
[1084] Knowing What You Know Is Not Enough: Large Language Model Confidences Don’t Align With Their Actions
Arka Pal, Teo Kitanovski, Arthur Liang, Akilesh Potti, Micah Goldblum
Main category: cs.LG
TL;DR: LLMs show an “action-belief gap” where their actions in interactive settings contradict their confidence estimates from static evaluations, revealing that good calibration doesn’t guarantee rational behavior in agentic workflows.
Details
Motivation: As LLMs are increasingly deployed in agentic and multi-turn workflows with significant consequences, reliable uncertainty estimation is crucial for risk management. Current confidence elicitation methods are evaluated on static datasets rather than interactive settings, creating a gap between measured confidence and actual behavior.Method: The study investigates the relationship between static confidence estimates and interactive behavior across three settings: prediction markets (betting against high-confidence predictions), tool-use (failing to invoke information-seeking tools when confidence is low), and user-challenge scenarios (changing high-confidence answers while sticking to low-confidence ones).
Result: LLMs frequently take actions that contradict their elicited confidences, showing a significant action-belief gap. Static calibration is insufficient for predicting consistency in dynamic settings - better calibrated models can be less consistent than smaller, weaker open-source counterparts.
Conclusion: Current evaluation methodologies have a critical blind spot: ensuring a model knows what it knows doesn’t guarantee it will act rationally on that knowledge. Confidence elicitation methods need to be evaluated in interactive, agentic settings rather than just static benchmarks.
Abstract: Large language models (LLMs) are increasingly deployed in agentic and multi-turn workflows where they are tasked to perform actions of significant consequence. In order to deploy them reliably and manage risky outcomes in these settings, it is helpful to access model uncertainty estimates. However, confidence elicitation methods for LLMs are typically not evaluated directly in agentic settings; instead, they are evaluated on static datasets, such as Q&A benchmarks. In this work we investigate the relationship between confidence estimates elicited in static settings and the behavior of LLMs in interactive settings. We uncover a significant action-belief gap – LLMs frequently take actions that contradict their elicited confidences. In a prediction market setting, we find that models often bet against their own high-confidence predictions; in a tool-use setting, models fail to reliably invoke information-seeking tools when their internal confidence is low; and in a user-challenge setting, models change their answers when they have high confidence in them, whilst sticking to answers they have low confidence in. Crucially, we show that static calibration is an insufficient predictor of consistency in the above dynamic settings, as stronger, better calibrated models are somtimes less consistent than their smaller and weaker open-source counterparts. Our results highlight a critical blind spot in current evaluation methodologies: ensuring that a model knows what it knows does not guarantee that it will act rationally on that knowledge.
[1085] On Evaluation of Unsupervised Feature Selection for Pattern Classification
Gyu-Il Kim, Dae-Won Kim, Jaesung Lee
Main category: cs.LG
TL;DR: Unsupervised feature selection evaluation should use multi-label datasets instead of single-label ones for fair comparison, as single-label evaluation can produce arbitrary rankings depending on which label is selected.
Details
Motivation: Current evaluation of unsupervised feature selection methods relies on single-label datasets, which are often created by arbitrarily selecting one label from multi-label data. This leads to inconsistent performance rankings that depend on which label happens to be chosen, making comparisons unreliable.Method: The study proposes using multi-label classification framework for evaluation instead of single-label. Experiments are conducted on 21 multi-label datasets using several representative unsupervised feature selection methods to compare performance rankings between single-label and multi-label settings.
Result: Experiments show that performance rankings of unsupervised feature selection methods differ markedly between single-label and multi-label evaluation settings. The rankings reported under single-label settings are inconsistent and unreliable compared to multi-label evaluation.
Conclusion: Multi-label evaluation provides a fairer and more reliable comparison framework for unsupervised feature selection methods than single-label evaluation, which produces arbitrary rankings depending on label selection.
Abstract: Unsupervised feature selection aims to identify a compact subset of features that captures the intrinsic structure of data without supervised label. Most existing studies evaluate the performance of methods using the single-label dataset that can be instantiated by selecting a label from multi-label data while maintaining the original features. Because the chosen label can vary arbitrarily depending on the experimental setting, the superiority among compared methods can be changed with regard to which label happens to be selected. Thus, evaluating unsupervised feature selection methods based solely on single-label accuracy is unreasonable for assessing their true discriminative ability. This study revisits this evaluation paradigm by adopting a multi-label classification framework. Experiments on 21 multi-label datasets using several representative methods demonstrate that performance rankings differ markedly from those reported under single-label settings, suggesting the possibility of multi-label evaluation settings for fair and reliable comparison of unsupervised feature selection methods.
[1086] LogSyn: A Few-Shot LLM Framework for Structured Insight Extraction from Unstructured General Aviation Maintenance Logs
Devansh Agarwal, Maitreyi Chatterjee, Biplab Chatterjee
Main category: cs.LG
TL;DR: LogSyn uses LLMs to convert unstructured aircraft maintenance logs into structured data through few-shot learning and controlled abstraction generation for improved safety analysis.
Details
Motivation: Aircraft maintenance logs contain valuable safety data but are underutilized due to their unstructured text format, making automated analysis difficult.Method: Uses Large Language Models with few-shot in-context learning on 6,169 records to perform Controlled Abstraction Generation (CAG) that summarizes problem-resolution narratives and classifies events within a hierarchical ontology.
Result: The framework successfully identifies key failure patterns and provides a scalable method for semantic structuring and actionable insight extraction from maintenance logs.
Conclusion: LogSyn offers a practical approach to improve maintenance workflows and predictive analytics in aviation and related industries by converting unstructured text into machine-readable structured data.
Abstract: Aircraft maintenance logs hold valuable safety data but remain underused due to their unstructured text format. This paper introduces LogSyn, a framework that uses Large Language Models (LLMs) to convert these logs into structured, machine-readable data. Using few-shot in-context learning on 6,169 records, LogSyn performs Controlled Abstraction Generation (CAG) to summarize problem-resolution narratives and classify events within a detailed hierarchical ontology. The framework identifies key failure patterns, offering a scalable method for semantic structuring and actionable insight extraction from maintenance logs. This work provides a practical path to improve maintenance workflows and predictive analytics in aviation and related industries.
[1087] Report for NSF Workshop on AI for Electronic Design Automation
Deming Chen, Vijay Ganesh, Weikai Li, Yingyan Celine Lin, Yong Liu, Subhasish Mitra, David Z. Pan, Ruchir Puri, Jason Cong, Yizhou Sun
Main category: cs.LG
TL;DR: NSF workshop report on applying AI techniques (LLMs, GNNs, RL) to Electronic Design Automation challenges across physical synthesis, high-level synthesis, optimization, and verification domains.
Details
Motivation: To explore how AI technologies can accelerate Electronic Design Automation (EDA) processes and shorten hardware design turnaround times by bringing together ML and EDA experts.Method: Workshop discussions organized around four themes: AI for physical synthesis/DFM, AI for high-level/logic-level synthesis, AI toolbox for optimization/design, and AI for test/verification, with recommendations for NSF investment.
Result: Identified specific AI applications across EDA domains and recommended NSF to foster AI/EDA collaboration, invest in foundational AI for EDA, develop data/compute infrastructure, and support workforce development.
Conclusion: AI has significant potential to transform EDA, requiring strategic investments in collaboration, infrastructure, and workforce to democratize hardware design and enable next-generation systems.
Abstract: This report distills the discussions and recommendations from the NSF Workshop on AI for Electronic Design Automation (EDA), held on December 10, 2024 in Vancouver alongside NeurIPS 2024. Bringing together experts across machine learning and EDA, the workshop examined how AI-spanning large language models (LLMs), graph neural networks (GNNs), reinforcement learning (RL), neurosymbolic methods, etc.-can facilitate EDA and shorten design turnaround. The workshop includes four themes: (1) AI for physical synthesis and design for manufacturing (DFM), discussing challenges in physical manufacturing process and potential AI applications; (2) AI for high-level and logic-level synthesis (HLS/LLS), covering pragma insertion, program transformation, RTL code generation, etc.; (3) AI toolbox for optimization and design, discussing frontier AI developments that could potentially be applied to EDA tasks; and (4) AI for test and verification, including LLM-assisted verification tools, ML-augmented SAT solving, security/reliability challenges, etc. The report recommends NSF to foster AI/EDA collaboration, invest in foundational AI for EDA, develop robust data infrastructures, promote scalable compute infrastructure, and invest in workforce development to democratize hardware design and enable next-generation hardware systems. The workshop information can be found on the website https://ai4eda-workshop.github.io/.
[1088] Decoupling and Damping: Structurally-Regularized Gradient Matching for Multimodal Graph Condensation
Lian Shen, Zhendan Chen, Meijia Song, Yinhui jiang, Ziming Su, Juan Liu, Xiangrong Liu
Main category: cs.LG
TL;DR: SR-GM is a graph condensation framework for multimodal graphs that addresses gradient conflicts between modalities and suppresses gradient noise propagation through structural regularization.
Details
Motivation: Multimodal graph learning faces computational bottlenecks with growing data scales. Existing graph condensation methods perform poorly in multimodal scenarios due to semantic misalignment causing gradient conflicts and graph neural networks amplifying gradient noise through message-passing.Method: Proposes Structural Regularized Gradient Matching (SR-GM) with two key components: (1) gradient decoupling mechanism to alleviate conflicts between modalities, and (2) structural damping regularizer to suppress gradient noise propagation in graph topology, transforming graph structure from noise amplifier to training stabilizer.
Result: Extensive experiments on four multimodal graph datasets demonstrate SR-GM’s effectiveness, showing state-of-the-art performance and cross-architecture generalization capabilities in multimodal graph dataset condensation.
Conclusion: SR-GM successfully addresses multimodal graph condensation challenges by handling gradient conflicts and noise propagation, providing an effective solution for compressing multimodal graph datasets while maintaining performance.
Abstract: In multimodal graph learning, graph structures that integrate information from multiple sources, such as vision and text, can more comprehensively model complex entity relationships. However, the continuous growth of their data scale poses a significant computational bottleneck for training. Graph condensation methods provide a feasible path forward by synthesizing compact and representative datasets. Nevertheless, existing condensation approaches generally suffer from performance limitations in multimodal scenarios, mainly due to two reasons: (1) semantic misalignment between different modalities leads to gradient conflicts; (2) the message-passing mechanism of graph neural networks further structurally amplifies such gradient noise. Based on this, we propose Structural Regularized Gradient Matching (SR-GM), a condensation framework for multimodal graphs. This method alleviates gradient conflicts between modalities through a gradient decoupling mechanism and introduces a structural damping regularizer to suppress the propagation of gradient noise in the topology, thereby transforming the graph structure from a noise amplifier into a training stabilizer. Extensive experiments on four multimodal graph datasets demonstrate the effectiveness of SR-GM, highlighting its state-of-the-art performance and cross-architecture generalization capabilities in multimodal graph dataset condensation.
[1089] Rethinking Cross-Modal Fine-Tuning: Optimizing the Interaction between Feature Alignment and Target Fitting
Trong Khiem Tran, Manh Cuong Dao, Phi Le Nguyen, Thao Nguyen Truong, Trong Nghia Hoang
Main category: cs.LG
TL;DR: A theoretical framework for adapting pre-trained models to new modalities by analyzing the interaction between feature alignment and target fine-tuning, with provable generalization bounds and improved performance.
Details
Motivation: The need to adapt pre-trained models to unseen feature modalities for cross-disciplinary knowledge integration, with a key challenge being how to align new modality representations with relevant parts of the pre-trained model's representation space for accurate knowledge transfer.Method: Develops a principled framework establishing provable generalization bounds on target error, explaining the interaction between feature alignment and target fitting through a novel concept of feature-label distortion, offering actionable insights for algorithm design.
Result: The resulting approach achieves significantly improved performance over state-of-the-art methods across a wide range of benchmark datasets.
Conclusion: The theoretical framework provides a principled understanding of feature alignment-target fitting interaction for modality adaptation, leading to practical algorithm design insights and superior performance.
Abstract: Adapting pre-trained models to unseen feature modalities has become increasingly important due to the growing need for cross-disciplinary knowledge integration. A key challenge here is how to align the representation of new modalities with the most relevant parts of the pre-trained model’s representation space to enable accurate knowledge transfer. This requires combining feature alignment with target fine-tuning, but uncalibrated combinations can exacerbate misalignment between the source and target feature-label structures and reduce target generalization. Existing work, however, lacks a theoretical understanding of this critical interaction between feature alignment and target fitting. To bridge this gap, we develop a principled framework that establishes a provable generalization bound on the target error, which explains the interaction between feature alignment and target fitting through a novel concept of feature-label distortion. This bound offers actionable insights into how this interaction should be optimized for practical algorithm design. The resulting approach achieves significantly improved performance over state-of-the-art methods across a wide range of benchmark datasets.
[1090] How to Purchase Labels? A Cost-Effective Approach Using Active Learning Markets
Xiwen Huang, Pierre Pinson
Main category: cs.LG
TL;DR: Active learning markets framework for purchasing labels to improve model training, with optimization-based market clearing, budget constraints, and threshold-based acquisition strategies.
Details
Motivation: Addresses the need for efficient label acquisition in machine learning when analysts need additional labeled data to improve model fitting or predictive analytics, contrasting with existing approaches that focus on purchasing features or examples.Method: Formalizes market clearing as an optimization problem with budget constraints and improvement thresholds. Uses single-buyer-multiple-seller setup with two active learning strategies (variance-based and query-by-committee) paired with distinct pricing mechanisms, compared against random sampling and greedy knapsack baselines.
Result: Validated on real-world datasets from real estate pricing and energy forecasting domains. Demonstrates robustness and consistently achieves superior performance with fewer labels acquired compared to conventional methods.
Conclusion: Provides an easy-to-implement practical solution for optimizing data acquisition in resource-constrained environments, offering efficient label purchasing strategies for model improvement.
Abstract: We introduce and analyse active learning markets as a way to purchase labels, in situations where analysts aim to acquire additional data to improve model fitting, or to better train models for predictive analytics applications. This comes in contrast to the many proposals that already exist to purchase features and examples. By originally formalising the market clearing as an optimisation problem, we integrate budget constraints and improvement thresholds into the label acquisition process. We focus on a single-buyer-multiple-seller setup and propose the use of two active learning strategies (variance based and query-by-committee based), paired with distinct pricing mechanisms. They are compared to benchmark baselines including random sampling and a greedy knapsack heuristic. The proposed strategies are validated on real-world datasets from two critical application domains: real estate pricing and energy forecasting. Results demonstrate the robustness of our approach, consistently achieving superior performance with fewer labels acquired compared to conventional methods. Our proposal comprises an easy-to-implement practical solution for optimising data acquisition in resource-constrained environments.
[1091] Rank-1 Approximation of Inverse Fisher for Natural Policy Gradients in Deep Reinforcement Learning
Yingxiao Huo, Satya Prakash Dash, Radu Stoican, Samuel Kaski, Mingfei Sun
Main category: cs.LG
TL;DR: Efficient natural policy optimization using rank-1 approximation to inverse Fisher Information Matrix for faster convergence with lower computational cost.
Details
Motivation: Natural gradients offer fast convergence in deep reinforcement learning but require computationally expensive inversion of Fisher Information Matrix at each iteration, making them impractical for large-scale applications.Method: Proposes a scalable natural policy optimization technique that uses rank-1 approximation to the full inverse Fisher Information Matrix, reducing computational complexity while maintaining convergence properties.
Result: The method achieves superior performance compared to standard actor-critic and trust-region baselines across diverse environments, with theoretical guarantees of faster convergence than policy gradients under certain conditions.
Conclusion: Rank-1 approximation to inverse-FIM provides an efficient and scalable approach to natural policy optimization that maintains convergence benefits while being computationally feasible for practical applications.
Abstract: Natural gradients have long been studied in deep reinforcement learning due to their fast convergence properties and covariant weight updates. However, computing natural gradients requires inversion of the Fisher Information Matrix (FIM) at each iteration, which is computationally prohibitive in nature. In this paper, we present an efficient and scalable natural policy optimization technique that leverages a rank-1 approximation to full inverse-FIM. We theoretically show that under certain conditions, a rank-1 approximation to inverse-FIM converges faster than policy gradients and, under some conditions, enjoys the same sample complexity as stochastic policy gradient methods. We benchmark our method on a diverse set of environments and show that it achieves superior performance to standard actor-critic and trust-region baselines.
[1092] RNNs perform task computations by dynamically warping neural representations
Arthur Pellegrino, Angus Chadwick
Main category: cs.LG
TL;DR: RNNs perform computations by dynamically warping their representations of task variables, which can be analyzed using Riemannian geometry to understand the link between computation-through-dynamics and representational geometry.
Details
Motivation: To bridge the gap between understanding how neural networks represent data features in their activations (neural representations) and how dynamical systems perform computations on time-varying input data, particularly focusing on the link between computation-through-dynamics and representational geometry.Method: Developed a Riemannian geometric framework that enables derivation of manifold topology and geometry of a dynamical system from its input manifold, then applied this to characterize the time-varying geometry of RNNs.
Result: Demonstrated that dynamic warping is a fundamental feature of RNN computations, showing how RNNs perform computations by dynamically warping their representations of task variables.
Conclusion: The Riemannian geometric framework successfully reveals the connection between computation-through-dynamics and representational geometry in RNNs, with dynamic warping being a core computational mechanism.
Abstract: Analysing how neural networks represent data features in their activations can help interpret how they perform tasks. Hence, a long line of work has focused on mathematically characterising the geometry of such “neural representations.” In parallel, machine learning has seen a surge of interest in understanding how dynamical systems perform computations on time-varying input data. Yet, the link between computation-through-dynamics and representational geometry remains poorly understood. Here, we hypothesise that recurrent neural networks (RNNs) perform computations by dynamically warping their representations of task variables. To test this hypothesis, we develop a Riemannian geometric framework that enables the derivation of the manifold topology and geometry of a dynamical system from the manifold of its inputs. By characterising the time-varying geometry of RNNs, we show that dynamic warping is a fundamental feature of their computations.
[1093] From Fuzzy to Exact: The Halo Architecture for Infinite-Depth Reasoning via Rational Arithmetic
Hansheng Ren
Main category: cs.LG
TL;DR: The paper argues that exact arithmetic (rational numbers) is essential for AGI reasoning, proposes Halo Architecture with custom hardware for exact computation, and shows it outperforms standard floating-point models in numerical fidelity.
Details
Motivation: Current deep learning prioritizes computational throughput over numerical precision, creating a trade-off that conflicts with requirements for general intelligence. The authors argue that high-order causal reasoning in AGI demands arbitrary-precision, logically consistent arithmetic, and trace LLM failures to limitations of IEEE 754 floating-point arithmetic.Method: Proposes Halo Architecture that transitions from approximate reals to exact rationals, implemented through a custom Exact Inference Unit (EIU) with asynchronous MIMD reduction and dual-modular redundancy. The architecture uses number-theoretic quantization with proven quadratic error decay.
Result: In simulations, 600B-parameter BF16 models fail in chaotic systems within steps, while Halo sustains perfect numerical fidelity indefinitely. The method theoretically proves quadratic error decay superior to linear barrier of standard fixed-point arithmetic.
Conclusion: Exact arithmetic is non-negotiable for advancing reasoning-capable AGI. The paper provides a co-designed hardware-software path toward verifiable, exascale-ready AI systems with Halo Architecture.
Abstract: The pursuit of scale in deep learning has entrenched a trade-off: computational throughput is prioritized at the expense of numerical precision. We argue this compromise is fundamentally at odds with the requirements of general intelligence. We propose the \textit{Exactness Hypothesis}: high-order causal reasoning – a cornerstone of AGI – demands a substrate supporting arbitrary-precision, logically consistent arithmetic. We trace prevalent LLM failures, such as logical hallucinations and incoherence, to the inherent limitations of IEEE 754 floating-point arithmetic, where approximation errors compound catastrophically in deep functions. As a solution, we present the Halo Architecture, which transitions the computational foundation from approximate reals ($\mathbb{R}$) to exact rationals ($\mathbb{Q}$). Halo is realized through a custom Exact Inference Unit (EIU), whose design – featuring asynchronous MIMD reduction and dual-modular redundancy – resolves the performance and reliability bottlenecks of exact computation at scale. Crucially, we theoretically prove that Halo’s number-theoretic quantization yields a quadratic error decay ($\mathcal{O}(D^{-2})$), strictly superior to the linear barrier of standard fixed-point arithmetic. In rigorous simulations, 600B-parameter BF16 models fail in chaotic systems within steps, while Halo sustains perfect numerical fidelity indefinitely. Our work posits exact arithmetic as non-negotiable for advancing reasoning-capable AGI and provides a co-designed hardware-software path toward verifiable, exascale-ready AI systems
[1094] Error-Free Linear Attention is a Free Lunch: Exact Solution from Continuous-Time Dynamics
Jingdi Lei, Di Zhang, Soujanya Poria
Main category: cs.LG
TL;DR: EFLA is a numerically stable linear-time attention mechanism that solves continuous-time dynamics exactly without error accumulation, achieving better performance than DeltaNet while maintaining linear complexity.
Details
Motivation: To address the quadratic cost bottleneck of softmax attention in long-context language models, while improving upon existing linear-time attention and State Space Models (SSMs) that may suffer from numerical instability or approximation errors.Method: Formulates online learning update as continuous-time dynamical system, leverages rank-1 structure of dynamics matrix to derive exact closed-form solution, achieving full parallelism and linear-time computation without approximation errors.
Result: EFLA achieves lower language modeling perplexity and superior downstream benchmark performance than DeltaNet without additional parameters, while being robust in noisy environments and theoretically free from error accumulation.
Conclusion: EFLA provides a new theoretical foundation for building high-fidelity, scalable linear-time attention models with exact solutions to continuous dynamics and linear-time complexity.
Abstract: Linear-time attention and State Space Models (SSMs) promise to solve the quadratic cost bottleneck in long-context language models employing softmax attention. We introduce Error-Free Linear Attention (EFLA), a numerically stable, full parallelism and generalized formulation of the delta rule. Specifically, we formulate the online learning update as a continuous-time dynamical system and prove that its exact solution is not only attainable but also computable in linear time with full parallelism. By leveraging the rank-1 structure of the dynamics matrix, we directly derive the exact closed-form solution effectively. This attention mechanism is theoretically free from error accumulation, perfectly capturing the continuous dynamics while preserving the linear-time complexity. Through an extensive suite of experiments, we show that EFLA enables robust performance in noisy environments, achieving lower language modeling perplexity and superior downstream benchmark performance than DeltaNet without introducing additional parameters. Our work provides a new theoretical foundation for building high-fidelity, scalable linear-time attention models.
[1095] FLAME: Flow Enhanced Legendre Memory Models for General Time Series Forecasting
Xingjian Wu, Hanyin Cheng, Xiangfei Qiu, Zhengyu Li, Jilin Hu, Chenjuan Guo, Bin Yang
Main category: cs.LG
TL;DR: FLAME is a lightweight time series foundation model family that supports both deterministic and probabilistic forecasting using Legendre Memory variants and Normalization Flow for efficient, robust predictions.
Details
Motivation: The paper aims to create efficient yet capable time series foundation models that can handle both deterministic and probabilistic forecasting, addressing the need for lightweight models with strong generalization capabilities in time series analysis.Method: FLAME uses Legendre Memory variants (LegT and LegS) in encoding and decoding phases to capture data inductive biases and enable efficient long-range inference. It employs a Normalization Flow-based forecasting head for generative probabilistic modeling of complex distributions.
Result: FLAME achieves state-of-the-art zero-shot performance on both deterministic and probabilistic forecasting tasks across benchmarks like TSFM-Bench and ProbTS, demonstrating consistent superior results.
Conclusion: FLAME provides an effective, lightweight solution for time series forecasting that balances efficiency with robust performance through its Legendre Memory architecture and generative probabilistic modeling approach.
Abstract: In this work, we introduce FLAME, a family of extremely lightweight and capable Time Series Foundation Models, which support both deterministic and probabilistic forecasting via generative probabilistic modeling, thus ensuring both efficiency and robustness. FLAME utilizes the Legendre Memory for strong generalization capabilities. Through adapting variants of Legendre Memory, i.e., translated Legendre (LegT) and scaled Legendre (LegS), in the Encoding and Decoding phases, FLAME can effectively capture the inherent inductive bias within data and make efficient long-range inferences. To enhance the accuracy of probabilistic forecasting while keeping efficient, FLAME adopts a Normalization Flow based forecasting head, which can model the arbitrarily intricate distributions over the forecasting horizon in a generative manner. Comprehensive experiments on well-recognized benchmarks, including TSFM-Bench and ProbTS, demonstrate the consistent state-of-the-art zero-shot performance of FLAME on both deterministic and probabilistic forecasting tasks.
[1096] Decoupled Split Learning via Auxiliary Loss
Anower Zihad, Felix Owino, Ming Tang, Chao Huang
Main category: cs.LG
TL;DR: A split learning method that replaces end-to-end backpropagation with local training using auxiliary classifiers, reducing communication by 50% and memory by up to 58% while maintaining performance.
Details
Motivation: Traditional split learning requires exchanging both forward activations and backward gradients every iteration, causing high communication overhead and memory usage for storing activations and gradients.Method: Client and server train semi-independently using local loss signals. Client adds small auxiliary classifier at split point for local error signal, server trains on client’s transmitted activations using true loss function, eliminating need for backward gradient transmission.
Result: Achieves performance comparable to standard split learning with backpropagation while reducing communication by 50% and peak memory usage by up to 58% on CIFAR-10 and CIFAR-100 datasets.
Conclusion: The beyond-backpropagation approach enables efficient split learning with significantly reduced communication and memory overhead while maintaining model performance.
Abstract: Split learning is a distributed training paradigm where a neural network is partitioned between clients and a server, which allows data to remain at the client while only intermediate activations are shared. Traditional split learning relies on end-to-end backpropagation across the client-server split point. This incurs a large communication overhead (i.e., forward activations and backward gradients need to be exchanged every iteration) and significant memory use (for storing activations and gradients). In this paper, we develop a beyond-backpropagation training method for split learning. In this approach, the client and server train their model partitions semi-independently, using local loss signals instead of propagated gradients. In particular, the client’s network is augmented with a small auxiliary classifier at the split point to provide a local error signal, while the server trains on the client’s transmitted activations using the true loss function. This decoupling removes the need to send backward gradients, which cuts communication costs roughly in half and also reduces memory overhead (as each side only stores local activations for its own backward pass). We evaluate our approach on CIFAR-10 and CIFAR-100. Our experiments show two key results. First, the proposed approach achieves performance on par with standard split learning that uses backpropagation. Second, it significantly reduces communication (of transmitting activations/gradient) by 50% and peak memory usage by up to 58%.
[1097] Generative Modeling through Koopman Spectral Analysis: An Operator-Theoretic Perspective
Yuanchao Xu, Fengyi Li, Masahiro Fujisawa, Xiaoyuan Cheng, Youssef Marzouk, Isao Ishikawa
Main category: cs.LG
TL;DR: KSWGD is a particle-based generative modeling framework that learns Langevin generators via Koopman theory and Wasserstein gradient descent, achieving linear convergence without vanishing gradients.
Details
Motivation: Existing kernel-based particle methods suffer from vanishing-gradient phenomena and slow convergence. The authors aim to develop a method that can learn the underlying distribution's spectral structure directly from trajectory data without needing explicit knowledge of the target potential.Method: KSWGD combines Koopman operator theory with Wasserstein gradient descent. It estimates the spectral structure of the underlying distribution from trajectory data via the Koopman operator, eliminating the need for explicit potential knowledge. The method maintains approximately constant dissipation rate to ensure linear convergence.
Result: Experiments on compact manifolds, metastable multi-well systems, and high-dimensional stochastic partial differential equations show KSWGD consistently outperforms baselines in both convergence speed and sample quality.
Conclusion: KSWGD provides an effective generative modeling framework that overcomes vanishing-gradient issues in existing methods, achieves linear convergence, and demonstrates superior performance across various challenging domains.
Abstract: We propose Koopman Spectral Wasserstein Gradient Descent (KSWGD), a particle-based generative modeling framework that learns the Langevin generator via Koopman theory and integrates it with Wasserstein gradient descent. Our key insight is that this spectral structure of the underlying distribution can be directly estimated from trajectory data via the Koopman operator, eliminating the need for explicit knowledge of the target potential. Additionally, we prove that KSWGD maintains an approximately constant dissipation rate, thereby establishing linear convergence and overcoming the vanishing-gradient phenomenon that hinders existing kernel-based particle methods. We further provide a Feynman–Kac interpretation that clarifies the method’s probabilistic foundation. Experiments on compact manifolds, metastable multi-well systems, and high-dimensional stochastic partial differential equations demonstrate that KSWGD consistently outperforms baselines in both convergence speed and sample quality.
[1098] Safe Exploration via Policy Priors
Manuel Wendl, Yarden As, Manish Prajapat, Anton Pollak, Stelian Coros, Andreas Krause
Main category: cs.LG
TL;DR: SOOPER is a safe RL method that uses conservative policy priors and probabilistic dynamics models to enable optimistic exploration with safety guarantees.
Details
Motivation: Safe exploration is crucial for RL agents to learn online beyond controlled environments, requiring methods that can guarantee safety while still allowing effective learning.Method: Uses suboptimal conservative policies as priors, combines probabilistic dynamics models for optimistic exploration with pessimistic fallback to conservative policies when needed.
Result: SOOPER guarantees safety throughout learning, converges to optimal policy with bounded cumulative regret, and outperforms state-of-the-art on safe RL benchmarks and real-world hardware.
Conclusion: SOOPER provides a scalable, theoretically-grounded approach to safe RL that balances exploration and safety using policy priors and probabilistic models.
Abstract: Safe exploration is a key requirement for reinforcement learning (RL) agents to learn and adapt online, beyond controlled (e.g. simulated) environments. In this work, we tackle this challenge by utilizing suboptimal yet conservative policies (e.g., obtained from offline data or simulators) as priors. Our approach, SOOPER, uses probabilistic dynamics models to optimistically explore, yet pessimistically fall back to the conservative policy prior if needed. We prove that SOOPER guarantees safety throughout learning, and establish convergence to an optimal policy by bounding its cumulative regret. Extensive experiments on key safe RL benchmarks and real-world hardware demonstrate that SOOPER is scalable, outperforms the state-of-the-art and validate our theoretical guarantees in practice.
[1099] Enhancing Newton-Kaczmarz training of Kolmogorov-Arnold networks through concurrency
Andrew Polar, Michael Poluektov
Main category: cs.LG
TL;DR: Concurrency-driven enhancements to Newton-Kaczmarz training for Kolmogorov-Arnold Networks (KANs) using pre-training, disjoint subset training with model merging, and FPGA parallelization to overcome sequential update limitations.
Details
Motivation: The NK-based training for KANs offers state-of-the-art performance but suffers from sequential parameter updates that limit acceleration potential. The paper aims to overcome this bottleneck through concurrency-driven enhancements.Method: Three complementary strategies: (1) pre-training procedure tailored to NK updates’ structure, (2) training on disjoint data subsets followed by model merging (not federated learning), and (3) FPGA parallelization technique implemented and tested on device.
Result: Substantial acceleration achieved through the proposed concurrency-driven enhancements, with fully reproducible experimental results and complete source codes available online.
Conclusion: The proposed concurrency-driven strategies successfully overcome the sequential update limitation in NK-based KAN training, enabling significant acceleration while maintaining state-of-the-art performance.
Abstract: The present paper introduces concurrency-driven enhancements to the training algorithm for the Kolmogorov-Arnold networks (KANs) that is based on the Newton-Kaczmarz (NK) method. As indicated by prior research, the NK-based training for KANs offers state-of-the-art performance in terms of accuracy and training time on relatively large datasets, significantly overtaking classical neural networks based on multilayer perceptrons (MLPs). Although some elements of the algorithm can be parallelised (in particular, evaluation of the basis functions’ values), a major limitation of the algorithm is the sequential application of the parameters’ updates, which has not been resolved up to now. However, substantial acceleration is achievable. Three complementary strategies are proposed in the present paper: (i) a pre-training procedure tailored to the NK updates’ structure, (ii) training on disjoint subsets of data, followed by models’ merging, not in the context of federated learning, but as a mechanism for accelerating the convergence, and (iii) a parallelisation technique suitable for execution on field-programmable gate arrays (FPGAs), which is implemented and tested directly on the device. All experimental results presented in this work are fully reproducible, with the complete source codes available online.
[1100] Membership Inference Attacks Against Fine-tuned Diffusion Language Models
Yuetian Chen, Kaiyuan Zhang, Yuntao Du, Edoardo Stoppa, Charles Fleming, Ashish Kundu, Bruno Ribeiro, Ninghui Li
Main category: cs.LG
TL;DR: First systematic investigation of Membership Inference Attacks (MIA) vulnerabilities in Diffusion Language Models (DLMs), introducing SAMA attack that exploits DLMs’ multiple maskable configurations for improved privacy leakage detection.
Details
Motivation: DLMs represent a promising alternative to autoregressive language models but their susceptibility to privacy leakage via Membership Inference Attacks remains critically underexplored, especially given their unique bidirectional masked token prediction architecture.Method: Introduces SAMA (Subset-Aggregated Membership Attack) which samples masked subsets across progressive densities and applies sign-based statistics with inverse-weighted aggregation to transform sparse memorization detection into robust voting mechanism.
Result: SAMA achieves 30% relative AUC improvement over best baseline, with up to 8 times improvement at low false positive rates across nine datasets, revealing significant previously unknown vulnerabilities in DLMs.
Conclusion: DLMs have significant MIA vulnerabilities due to their multiple maskable configurations, necessitating development of tailored privacy defenses for this emerging class of language models.
Abstract: Diffusion Language Models (DLMs) represent a promising alternative to autoregressive language models, using bidirectional masked token prediction. Yet their susceptibility to privacy leakage via Membership Inference Attacks (MIA) remains critically underexplored. This paper presents the first systematic investigation of MIA vulnerabilities in DLMs. Unlike the autoregressive models’ single fixed prediction pattern, DLMs’ multiple maskable configurations exponentially increase attack opportunities. This ability to probe many independent masks dramatically improves detection chances. To exploit this, we introduce SAMA (Subset-Aggregated Membership Attack), which addresses the sparse signal challenge through robust aggregation. SAMA samples masked subsets across progressive densities and applies sign-based statistics that remain effective despite heavy-tailed noise. Through inverse-weighted aggregation prioritizing sparse masks’ cleaner signals, SAMA transforms sparse memorization detection into a robust voting mechanism. Experiments on nine datasets show SAMA achieves 30% relative AUC improvement over the best baseline, with up to 8 times improvement at low false positive rates. These findings reveal significant, previously unknown vulnerabilities in DLMs, necessitating the development of tailored privacy defenses.
[1101] PairFlow: Closed-Form Source-Target Coupling for Few-Step Generation in Discrete Flow Models
Mingue Park, Jisung Hwang, Seungwoo Yoo, Kyeongmin Yeo, Minhyuk Sung
Main category: cs.LG
TL;DR: PairFlow is a lightweight preprocessing method for Discrete Flow Models that enables few-step sampling without needing pretrained teachers, using closed-form inversion to create paired source-target samples efficiently.
Details
Motivation: Discrete Flow Models (DFMs) show strong generative performance for discrete data but suffer from slow iterative sampling. Existing acceleration methods require expensive finetuning with substantial training overhead, creating a need for more efficient approaches.Method: PairFlow uses a closed-form inversion for DFMs to efficiently construct paired source-target samples, training DFMs directly from coupled distributions without pretrained teachers. This preprocessing step is lightweight and computationally cheap.
Result: PairFlow achieves performance matching or surpassing two-stage finetuning approaches while using only up to 1.7% of full training compute. It also provides stronger base models for subsequent distillation, enabling further acceleration after finetuning.
Conclusion: PairFlow offers an efficient, broadly applicable solution for accelerating Discrete Flow Models, enabling few-step sampling with minimal computational overhead and strong performance across molecular data and image domains.
Abstract: We introduce $\texttt{PairFlow}$, a lightweight preprocessing step for training Discrete Flow Models (DFMs) to achieve few-step sampling without requiring a pretrained teacher. DFMs have recently emerged as a new class of generative models for discrete data, offering strong performance. However, they suffer from slow sampling due to their iterative nature. Existing acceleration methods largely depend on finetuning, which introduces substantial additional training overhead. $\texttt{PairFlow}$ addresses this issue with a lightweight preprocessing step. Inspired by ReFlow and its extension to DFMs, we train DFMs from coupled samples of source and target distributions, without requiring any pretrained teacher. At the core of our approach is a closed-form inversion for DFMs, which allows efficient construction of paired source-target samples. Despite its extremely low cost, taking only up to 1.7% of the compute needed for full model training, $\texttt{PairFlow}$ matches or even surpasses the performance of two-stage training involving finetuning. Furthermore, models trained with our framework provide stronger base models for subsequent distillation, yielding further acceleration after finetuning. Experiments on molecular data as well as binary and RGB images demonstrate the broad applicability and effectiveness of our approach.
[1102] Conditional PED-ANOVA: Hyperparameter Importance in Hierarchical & Dynamic Search Spaces
Kaito Baba, Yoshihiko Ozaki, Shuhei Watanabe
Main category: cs.LG
TL;DR: condPED-ANOVA extends hyperparameter importance estimation to conditional search spaces where hyperparameter presence/domain depends on other hyperparameters.
Details
Motivation: Existing hyperparameter importance (HPI) estimators like PED-ANOVA assume fixed, unconditional search spaces and cannot properly handle conditional hyperparameters, leading to misleading or uninterpretable importance estimates in conditional settings.Method: Introduces conditional HPI for top-performing regions and derives a closed-form estimator that accurately reflects conditional activation and domain changes in hyperparameter spaces.
Result: Experiments show naive adaptations of existing HPI estimators yield misleading results, while condPED-ANOVA consistently provides meaningful importances that reflect the underlying conditional structure.
Conclusion: condPED-ANOVA provides a principled framework for accurate hyperparameter importance estimation in conditional search spaces, addressing limitations of existing methods.
Abstract: We propose conditional PED-ANOVA (condPED-ANOVA), a principled framework for estimating hyperparameter importance (HPI) in conditional search spaces, where the presence or domain of a hyperparameter can depend on other hyperparameters. Although the original PED-ANOVA provides a fast and efficient way to estimate HPI within the top-performing regions of the search space, it assumes a fixed, unconditional search space and therefore cannot properly handle conditional hyperparameters. To address this, we introduce a conditional HPI for top-performing regions and derive a closed-form estimator that accurately reflects conditional activation and domain changes. Experiments show that naive adaptations of existing HPI estimators yield misleading or uninterpretable importances in conditional settings, whereas condPED-ANOVA consistently provides meaningful importances that reflect the underlying conditional structure. Our code is publicly available at https://github.com/kAIto47802/condPED-ANOVA.
[1103] Categorical Reparameterization with Denoising Diffusion models
Samson Gourevitch, Alain Durmus, Eric Moulines, Jimmy Olsson, Yazid Janati
Main category: cs.LG
TL;DR: ReDGE: A novel diffusion-based soft reparameterization method for categorical distributions that enables efficient gradient estimation for discrete variables in optimization problems.
Details
Motivation: Optimizing models with categorical variables is challenging due to the non-differentiability of categorical sampling, requiring workarounds like continuous relaxations to enable gradient-based optimization.Method: Introduces ReDGE, a diffusion-based soft reparameterization method that defines a flexible class of gradient estimators for categorical distributions, including the Straight-Through estimator as a special case.
Result: Experiments on latent variable models and inference-time reward guidance in discrete diffusion models show ReDGE consistently matches or outperforms existing gradient-based methods.
Conclusion: ReDGE provides an efficient and effective approach for gradient estimation in categorical distributions, advancing optimization techniques for discrete variables in machine learning models.
Abstract: Learning models with categorical variables requires optimizing expectations over discrete distributions, a setting in which stochastic gradient-based optimization is challenging due to the non-differentiability of categorical sampling. A common workaround is to replace the discrete distribution with a continuous relaxation, yielding a smooth surrogate that admits reparameterized gradient estimates via the reparameterization trick. Building on this idea, we introduce ReDGE, a novel and efficient diffusion-based soft reparameterization method for categorical distributions. Our approach defines a flexible class of gradient estimators that includes the Straight-Through estimator as a special case. Experiments spanning latent variable models and inference-time reward guidance in discrete diffusion models demonstrate that ReDGE consistently matches or outperforms existing gradient-based methods. The code will be made available at https://github.com/samsongourevitch/redge.
[1104] Solver-in-the-Loop: MDP-Based Benchmarks for Self-Correction and Behavioral Rationality in Operations Research
Ruicheng Ao, David Simchi-Levi, Xinshang Wang
Main category: cs.LG
TL;DR: New benchmarks ORDebug and ORBias evaluate LLMs on iterative debugging of infeasible optimization models and behavioral rationality in newsvendor problems, showing domain-specific training outperforms scale.
Details
Motivation: Existing LLM benchmarks for Operations Research only test one-shot code generation, ignoring the crucial iterative debugging process that practitioners actually use to fix infeasible models.Method: Created two benchmarks: ORDebug (5,000+ problems with 9 error types) tests iterative self-correction with solver feedback; ORBias (2,000 newsvendor instances) measures systematic deviations from optimal policies. Evaluated 26 models with 12,000+ samples.
Result: Domain-specific RLVR training enabled an 8B model to surpass frontier APIs: 95.3% vs 86.2% recovery rate, 62.4% vs 47.8% diagnostic accuracy, and 2.25 vs 3.78 steps to resolution. Curriculum training achieved negative bias drift (-9.6%), reducing systematic bias by 48%.
Conclusion: Process-level evaluation with verifiable oracles enables targeted training that outperforms scale, demonstrating the importance of evaluating LLMs in realistic iterative workflows rather than one-shot tasks.
Abstract: Operations Research practitioners routinely debug infeasible models through an iterative process: analyzing Irreducible Infeasible Subsystems (\IIS{}), identifying constraint conflicts, and systematically repairing formulations until feasibility is achieved. Yet existing LLM benchmarks evaluate OR as one-shot translation – given a problem description, generate solver code – ignoring this diagnostic loop entirely. We introduce two benchmarks that place the \textbf{solver in the evaluation loop}. \textbf{\ORDebug{}} evaluates iterative self-correction through 5,000+ problems spanning 9 error types; each repair action triggers solver re-execution and \IIS{} recomputation, providing deterministic, verifiable feedback. \textbf{\ORBias{}} evaluates behavioral rationality through 2,000 newsvendor instances (1,000 ID + 1,000 OOD), measuring systematic deviations from closed-form optimal policies. Across 26 models and 12,000+ samples, we find that domain-specific RLVR training enables an 8B model to surpass frontier APIs: 95.3% vs 86.2% recovery rate (+9.1%), 62.4% vs 47.8% diagnostic accuracy (+14.6%), and 2.25 vs 3.78 steps to resolution (1.7$\times$ faster). On \ORBias{}, curriculum training achieves the only negative ID$\rightarrow$OOD bias drift among models evaluated (-9.6%), reducing systematic bias by 48% (from 20.0% to 10.4%). These results demonstrate that process-level evaluation with verifiable oracles enables targeted training that outperforms scale.
[1105] RealPDEBench: A Benchmark for Complex Physical Systems with Real-World Data
Peiyan Hu, Haodong Feng, Hongyuan Liu, Tongtong Yan, Wenhao Deng, Tianrun Gao, Rong Zheng, Haoren Zheng, Chenglei Yu, Chuanrui Wang, Kaiwen Li, Zhi-Ming Ma, Dezhi Zhou, Xingcai Lu, Dixia Fan, Tailin Wu
Main category: cs.LG
TL;DR: RealPDEBench: First benchmark integrating real-world measurements with paired numerical simulations for scientific ML, focusing on bridging sim-to-real gap in complex physical systems.
Details
Motivation: Current scientific ML models are limited by lack of real-world data, being trained mostly on simulations, which hinders development, evaluation, and sim-to-real transfer research.Method: Introduces benchmark with 5 real-world measured datasets paired with simulations, defines 3 comparison tasks, designs 8 evaluation metrics (data-oriented and physics-oriented), and benchmarks 10 representative baselines including SOTA models and pretrained PDE foundation models.
Result: Experiments reveal significant discrepancies between simulated and real-world data, while showing that pretraining with simulated data consistently improves both accuracy and convergence.
Conclusion: Provides insights from real-world data to advance scientific ML toward bridging sim-to-real gap and enabling real-world deployment.
Abstract: Predicting the evolution of complex physical systems remains a central problem in science and engineering. Despite rapid progress in scientific Machine Learning (ML) models, a critical bottleneck is the lack of expensive real-world data, resulting in most current models being trained and validated on simulated data. Beyond limiting the development and evaluation of scientific ML, this gap also hinders research into essential tasks such as sim-to-real transfer. We introduce RealPDEBench, the first benchmark for scientific ML that integrates real-world measurements with paired numerical simulations. RealPDEBench consists of five datasets, three tasks, eight metrics, and ten baselines. We first present five real-world measured datasets with paired simulated datasets across different complex physical systems. We further define three tasks, which allow comparisons between real-world and simulated data, and facilitate the development of methods to bridge the two. Moreover, we design eight evaluation metrics, spanning data-oriented and physics-oriented metrics, and finally benchmark ten representative baselines, including state-of-the-art models, pretrained PDE foundation models, and a traditional method. Experiments reveal significant discrepancies between simulated and real-world data, while showing that pretraining with simulated data consistently improves both accuracy and convergence. In this work, we hope to provide insights from real-world data, advancing scientific ML toward bridging the sim-to-real gap and real-world deployment. Our benchmark, datasets, and instructions are available at https://realpdebench.github.io/.
[1106] SAGE: Sequence-level Adaptive Gradient Evolution for Generative Recommendation
Yu Xie, Xing Kai Ren, Ying Qi, Hu Yao
Main category: cs.LG
TL;DR: SAGE introduces a unified optimization framework for list-wise generative recommendation that addresses limitations of existing LLM-based recommender systems by enabling reuse of native LLM vocabularies and solving the “Symmetric Conservatism” problem through adaptive gradient evolution.
Details
Motivation: Current LLM-based recommender systems like OneRec require separate vocabularies, leading to high maintenance costs and poor scalability. Additionally, their optimization strategy (GBPO) suffers from "Symmetric Conservatism" that suppresses cold-start item updates and fails to prevent diversity collapse in noisy environments.Method: Proposes SAGE framework with two innovations: 1) Sequence-level Signal Decoupling using geometric mean importance ratio with decoupled multi-objective advantages to eliminate token-level variance and resolve “Reward Collapse”; 2) Asymmetric Adaptive Dynamics with dynamic gradient manifold that applies “Boost Factor” to cold-start items and “Entropy Aware Penalty” to break information cocoons.
Result: Theoretical analysis and empirical results show SAGE effectively unblocks cold-start traffic and sustains recommendation diversity while maintaining the numerical stability of GBPO.
Conclusion: SAGE provides a unified optimization framework that enables efficient reuse of open-source LLM architectures without separate vocabularies and addresses critical limitations in existing generative recommendation systems through adaptive gradient evolution.
Abstract: While works such as OneRec have validated the scaling laws of Large Language Models (LLMs) in recommender systems, they rely on a cumbersome separate vocabulary. This dependency prevents the model architecture from reusing native LLM vocabularies, resulting in high maintenance costs and poor scalability. In response, we aim to efficiently reuse open-source LLM architectures without constructing a separate tokenization vocabulary. Furthermore, we identify that the optimization strategy of OneRec Gradient Bounded Policy Optimization (GBPO),suffers from a “Symmetric Conservatism” problem: its static gradient boundaries structurally suppress the update momentum required for cold-start items and fail to prevent diversity collapse in high-noise environments.To address this issue, we propose SAGE (Sequence-level Adaptive Gradient Evolution), a unified optimization framework tailored for list-wise generative recommendation. SAGE introduces two key innovations:(1) Sequence-level Signal Decoupling: By combining a geometric mean importance ratio with decoupled multi-objective advantages, we eliminate token-level variance and resolve the “Reward Collapse” problem. (2) Asymmetric Adaptive Dynamics: We construct a dynamic gradient manifold that applies a “Boost Factor” to high-potential cold start items to achieve super-linear updates and employs an “Entropy Aware Penalty” to break information cocoons. Theoretical analysis and empirical results demonstrate that SAGE effectively unblocks cold-start traffic and sustains recommendation diversity, all while retaining the numerical stability of GBPO.
[1107] Distribution-Guided and Constrained Quantum Machine Unlearning
Nausherwan Malik, Zubair Khalid, Muhammad Faryad
Main category: cs.LG
TL;DR: A distribution-guided framework for class-level quantum machine unlearning that treats unlearning as constrained optimization with tunable target distributions and anchor-based preservation constraints.
Details
Motivation: Existing quantum machine unlearning approaches rely on fixed, uniform target distributions and lack explicit control over the trade-off between forgetting and retained model behavior, motivating a more flexible and controlled framework.Method: Proposes a distribution-guided framework treating unlearning as constrained optimization with tunable target distributions derived from model similarity statistics, decoupling forgotten-class suppression from redistribution assumptions, and incorporating anchor-based preservation constraints to maintain predictive behavior on selected retained data.
Result: Evaluation on variational quantum classifiers trained on Iris and Covertype datasets shows sharp suppression of forgotten-class confidence, minimal degradation of retained-class performance, and closer alignment with gold retrained model baselines compared to uniform-target unlearning.
Conclusion: The findings highlight the importance of target design and constraint-based formulations for reliable and interpretable quantum machine unlearning, providing a more controlled approach to managing the forgetting-retention trade-off.
Abstract: Machine unlearning aims to remove the influence of specific training data from a learned model without full retraining. While recent work has begun to explore unlearning in quantum machine learning, existing approaches largely rely on fixed, uniform target distributions and do not explicitly control the trade-off between forgetting and retained model behaviour. In this work, we propose a distribution-guided framework for class-level quantum machine unlearning that treats unlearning as a constrained optimization problem. Our method introduces a tunable target distribution derived from model similarity statistics, decoupling the suppression of forgotten-class confidence from assumptions about redistribution among retained classes. We further incorporate an anchor-based preservation constraint that explicitly maintains predictive behaviour on selected retained data, yielding a controlled optimization trajectory that limits deviation from the original model. We evaluate the approach on variational quantum classifiers trained on the Iris and Covertype datasets. Results demonstrate sharp suppression of forgotten-class confidence, minimal degradation of retained-class performance, and closer alignment with the gold retrained model baselines compared to uniform-target unlearning. These findings highlight the importance of target design and constraint-based formulations for reliable and interpretable quantum machine unlearning.
[1108] HER: Human-like Reasoning and Reinforcement Learning for LLM Role-playing
Chengyu Du, Xintao Wang, Aili Chen, Weiyuan Li, Rui Xu, Junteng Liu, Zishan Huang, Rong Tian, Zijun Sun, Yuhao Li, Liheng Feng, Deming Ding, Pengyu Zhao, Yanghua Xiao
Main category: cs.LG
TL;DR: HER framework enables cognitive-level persona simulation in LLMs using dual-layer thinking (first-person character thoughts vs third-person LLM reasoning) trained with reverse-engineered reasoning data and human-aligned reward models.
Details
Motivation: Current LLM role-playing captures character tones and knowledge but fails to simulate the inner thoughts behind behaviors. There's a need for cognitive simulation with high-quality reasoning traces and reliable human-aligned reward signals.Method: Proposes HER framework with dual-layer thinking distinguishing character’s first-person thinking from LLM’s third-person thinking. Creates reasoning-augmented role-playing data via reverse engineering, constructs human-aligned principles and reward models, and trains models on Qwen3-32B using supervised and reinforcement learning.
Result: HER models significantly outperform Qwen3-32B baseline, achieving 30.26 improvement on CoSER benchmark and 14.97 gain on Minimax Role-Play Bench. Demonstrates effective cognitive-level persona simulation.
Conclusion: HER framework successfully addresses cognitive simulation in LLM role-playing through dual-layer thinking and human-aligned training, enabling more authentic persona simulation with inner thought processes.
Abstract: LLM role-playing, i.e., using LLMs to simulate specific personas, has emerged as a key capability in various applications, such as companionship, content creation, and digital games. While current models effectively capture character tones and knowledge, simulating the inner thoughts behind their behaviors remains a challenge. Towards cognitive simulation in LLM role-play, previous efforts mainly suffer from two deficiencies: data with high-quality reasoning traces, and reliable reward signals aligned with human preferences. In this paper, we propose HER, a unified framework for cognitive-level persona simulation. HER introduces dual-layer thinking, which distinguishes characters’ first-person thinking from LLMs’ third-person thinking. To bridge these gaps, we curate reasoning-augmented role-playing data via reverse engineering and construct human-aligned principles and reward models. Leveraging these resources, we train HER models based on Qwen3-32B via supervised and reinforcement learning. Extensive experiments validate the effectiveness of our approach. Notably, our models significantly outperform the Qwen3-32B baseline, achieving a 30.26 improvement on the CoSER benchmark and a 14.97 gain on the Minimax Role-Play Bench. Our datasets, principles, and models will be released to facilitate future research.
[1109] A Dual Pipeline Machine Learning Framework for Automated Multi Class Sleep Disorder Screening Using Hybrid Resampling and Ensemble Learning
Md Sultanul Islam Ovi, Muhsina Tarannum Munfa, G. M. M Miftahul Alam Adib, Syed Sabbir Hasan
Main category: cs.LG
TL;DR: A dual-pipeline ML framework for sleep disorder screening achieves 98.67% accuracy using statistical and wrapper-based feature selection with hybrid resampling for class imbalance.
Details
Motivation: Clinical sleep studies are resource-intensive and difficult to scale for population-level screening, necessitating automated methods for accurate classification of sleep disorders like insomnia and sleep apnea to reduce health risks and improve patient quality of life.Method: Dual-pipeline framework with: 1) statistical pipeline using Mutual Information and Linear Discriminant Analysis for linear separability, and 2) wrapper-based pipeline using Boruta feature selection with autoencoder for non-linear representation learning. Uses SMOTETomek hybrid resampling for class imbalance.
Result: Extra Trees and K Nearest Neighbors achieved 98.67% accuracy, outperforming recent baselines on the same dataset. Statistical testing shows significant improvement, with inference latency below 400 milliseconds.
Conclusion: The dual-pipeline design supports accurate and efficient automated screening for non-invasive sleep disorder risk stratification, enabling scalable population-level screening.
Abstract: Accurate classification of sleep disorders, particularly insomnia and sleep apnea, is important for reducing long term health risks and improving patient quality of life. However, clinical sleep studies are resource intensive and are difficult to scale for population level screening. This paper presents a Dual Pipeline Machine Learning Framework for multi class sleep disorder screening using the Sleep Health and Lifestyle dataset. The framework consists of two parallel processing streams: a statistical pipeline that targets linear separability using Mutual Information and Linear Discriminant Analysis, and a wrapper based pipeline that applies Boruta feature selection with an autoencoder for non linear representation learning. To address class imbalance, we use the hybrid SMOTETomek resampling strategy. In experiments, Extra Trees and K Nearest Neighbors achieved an accuracy of 98.67%, outperforming recent baselines on the same dataset. Statistical testing using the Wilcoxon Signed Rank Test indicates that the improvement over baseline configurations is significant, and inference latency remains below 400 milliseconds. These results suggest that the proposed dual pipeline design supports accurate and efficient automated screening for non invasive sleep disorder risk stratification.
[1110] Leveraging Soft Prompts for Privacy Attacks in Federated Prompt Tuning
Quan Minh Nguyen, Min-Seon Kim, Hoang M. Ngo, Trong Nghia Hoang, Hyuk-Yoon Kwon, My T. Thai
Main category: cs.LG
TL;DR: PromptMIA: A membership inference attack targeting federated prompt-tuning that allows malicious servers to determine if specific data points are in clients’ private datasets by monitoring adversarially crafted prompts.
Details
Motivation: While defenses against membership inference attacks in standard federated learning have been studied, the shift toward federated fine-tuning (particularly prompt-tuning) introduces new, unexplored attack surfaces that pose significant privacy threats.Method: Proposes PromptMIA, where a malicious server inserts adversarially crafted prompts and monitors their updates during collaborative training to infer membership. Formalizes the threat as a security game and provides theoretical analysis establishing a lower bound on attack advantage.
Result: PromptMIA consistently achieves high advantage across diverse benchmark datasets. Standard membership inference defenses developed for gradient or output based attacks show limited effectiveness against this new threat, highlighting non-trivial challenges.
Conclusion: Federated prompt-tuning exposes new privacy vulnerabilities requiring specifically tailored defense strategies. Current defenses are insufficient, underscoring the need for new approaches to protect against prompt-based membership inference attacks in federated settings.
Abstract: Membership inference attack (MIA) poses a significant privacy threat in federated learning (FL) as it allows adversaries to determine whether a client’s private dataset contains a specific data sample. While defenses against membership inference attacks in standard FL have been well studied, the recent shift toward federated fine-tuning has introduced new, largely unexplored attack surfaces. To highlight this vulnerability in the emerging FL paradigm, we demonstrate that federated prompt-tuning, which adapts pre-trained models with small input prefixes to improve efficiency, also exposes a new vector for privacy attacks. We propose PromptMIA, a membership inference attack tailored to federated prompt-tuning, in which a malicious server can insert adversarially crafted prompts and monitors their updates during collaborative training to accurately determine whether a target data point is in a client’s private dataset. We formalize this threat as a security game and empirically show that PromptMIA consistently attains high advantage in this game across diverse benchmark datasets. Our theoretical analysis further establishes a lower bound on the attack’s advantage which explains and supports the consistently high advantage observed in our empirical results. We also investigate the effectiveness of standard membership inference defenses originally developed for gradient or output based attacks and analyze their interaction with the distinct threat landscape posed by PromptMIA. The results highlight non-trivial challenges for current defenses and offer insights into their limitations, underscoring the need for defense strategies that are specifically tailored to prompt-tuning in federated settings.
[1111] Free-RBF-KAN: Kolmogorov-Arnold Networks with Adaptive Radial Basis Functions for Efficient Function Learning
Shao-Ting Chiu, Siu Wun Cheung, Ulisses Braga-Neto, Chak Shing Lee, Rui Peng Li
Main category: cs.LG
TL;DR: Free-RBF-KAN improves Kolmogorov-Arnold Networks by replacing B-splines with learnable radial basis functions, achieving comparable accuracy with faster training/inference through adaptive grids and trainable smoothness parameters.
Details
Motivation: Original KANs using B-splines suffer from computational overhead from the De Boor algorithm, while recent RBF-based variants sacrifice approximation accuracy. There's a need for an efficient yet accurate KAN architecture.Method: Proposes Free-RBF-KAN with adaptive learning grids and trainable smoothness parameters. Uses learnable RBF shapes that dynamically align with activation patterns, and provides the first formal universal approximation proof for RBF-KAN family.
Result: Achieves accuracy comparable to B-spline KANs while delivering significantly faster training and inference. Validated across multiscale regression, physics-informed PDEs, and operator learning tasks.
Conclusion: Free-RBF-KAN establishes an efficient and adaptive alternative for high-dimensional structured modeling tasks, bridging the gap between computational efficiency and approximation accuracy in KAN architectures.
Abstract: Kolmogorov-Arnold Networks (KANs) offer a promising framework for approximating complex nonlinear functions, yet the original B-spline formulation suffers from significant computational overhead due to De Boor algorithm. While recent RBF-based variants improve efficiency, they often sacrifice the approximation accuracy inherent in the original spline-based design. To bridge this gap, we propose Free-RBF-KAN, an architecture that integrates adaptive learning grids and trainable smoothness parameters to enable expressive, high-resolution function approximation. Our method utilizes learnable RBF shapes that dynamically align with activation patterns, and we provide the first formal universal approximation proof for the RBF-KAN family. Empirical evaluations across multiscale regression, physics-informed PDEs, and operator learning demonstrate that Free-RBF-KAN can achieve accuracy comparable to its B-spline counterparts while delivering significantly faster training and inference. These results establish Free-RBF-KAN as an efficient and adaptive alternative for high-dimensional structured modeling tasks.
[1112] BalDRO: A Distributionally Robust Optimization based Framework for Large Language Model Unlearning
Pengyang Shao, Naixin Zhai, Lei Chen, Yonghui Yang, Fengbin Zhu, Xun Yang, Meng Wang
Main category: cs.LG
TL;DR: BalDRO: A balanced LLM unlearning framework addressing sample-wise imbalance in forget sets using min-sup optimization with worst-case distribution identification
Details
Motivation: As LLMs shape online content, targeted information removal (unlearning) becomes crucial for web governance. A key challenge is sample-wise imbalance in forget sets where different samples have varying unlearning difficulty, leading to asynchronous forgetting - some knowledge remains insufficiently erased while others become over-forgotten.Method: BalDRO formulates unlearning as a min-sup process: inner step identifies worst-case data distribution emphasizing hard-to-unlearn samples, outer step updates model parameters under this distribution. Two efficient variants: BalDRO-G (discrete GroupDRO-based approximation focusing on high-loss subsets) and BalDRO-DV (continuous Donsker-Varadhan dual method enabling smooth adaptive weighting).
Result: Experiments on TOFU and MUSE datasets show BalDRO significantly improves both forgetting quality and model utility over existing methods.
Conclusion: BalDRO provides an effective framework for balanced LLM unlearning that addresses sample-wise imbalance, improving both forgetting completeness and model preservation.
Abstract: As Large Language Models (LLMs) increasingly shape online content, removing targeted information from well-trained LLMs (also known as LLM unlearning) has become critical for web governance. A key challenge lies in sample-wise imbalance within the forget set: different samples exhibit widely varying unlearning difficulty, leading to asynchronous forgetting where some knowledge remains insufficiently erased while others become over-forgotten. To address this, we propose BalDRO, a novel and efficient framework for balanced LLM unlearning. BalDRO formulates unlearning as a min-sup process: an inner step identifies a worst-case data distribution that emphasizes hard-to-unlearn samples, while an outer step updates model parameters under this distribution. We instantiate BalDRO via two efficient variants: BalDRO-G, a discrete GroupDRO-based approximation focusing on high-loss subsets, and BalDRO-DV, a continuous Donsker-Varadhan dual method enabling smooth adaptive weighting within standard training pipelines. Experiments on TOFU and MUSE show that BalDRO significantly improves both forgetting quality and model utility over existing methods, and we release code for reproducibility.
[1113] Global Optimization By Gradient from Hierarchical Score-Matching Spaces
Ming Li
Main category: cs.LG
TL;DR: A novel optimization method that unifies constrained optimization problems as hierarchical unconstrained objectives optimized via score matching gradients, revealing connections between global optimization and diffusion-based generative modeling.
Details
Motivation: Gradient-based optimization methods face limitations including local optima traps, simple convex constraints, continuous differentiability requirements, and difficulty scaling to high-dimensional complex problems. The authors aim to overcome these limitations by developing a more general optimization framework.Method: The method transforms all optimization problems with complex constraints into a general hierarchical optimization objective without constraints. This unconstrained objective is then optimized using gradients obtained through score matching techniques, which connect to diffusion-based generative modeling approaches.
Result: The proposed method is validated through both simple-constructed experiments and complex-practical experiments, demonstrating its effectiveness in overcoming traditional gradient-based optimization limitations.
Conclusion: The work successfully addresses limitations of gradient-based optimization methods and reveals a profound connection between global optimization and diffusion-based generative modeling through the score matching framework.
Abstract: Gradient-based methods are widely used to solve various optimization problems, however, they are either constrained by local optima dilemmas, simple convex constraints, and continuous differentiability requirements, or limited to low-dimensional simple problems. This work solve these limitations and restrictions by unifying all optimization problems with various complex constraints as a general hierarchical optimization objective without constraints, which is optimized by gradient obtained through score matching. The proposed method is verified through simple-constructed and complex-practical experiments. Even more importantly, it reveals the profound connection between global optimization and diffusion based generative modeling.
[1114] OLion: Approaching the Hadamard Ideal by Intersecting Spectral and $\ell_{\infty}$ Implicit Biases
Zixiao Wang, Yifei Shen, Huishuai Zhang
Main category: cs.LG
TL;DR: Spectral-L∞ optimizer (SL∞) combines spectral control from orthogonalized updates with coordinate control from sign updates, forming a Lion-style momentum direction with efficient approximation to spectral and ℓ∞ constraints.
Details
Motivation: Many optimizers inherit implicit biases from norm-induced geometries; the paper aims to combine spectral control (orthogonalized updates) with coordinate control (sign updates) to create an efficient optimizer that matches or outperforms existing methods while using less memory.Method: SL∞ forms a Lion-style momentum direction, approximately orthogonalizes it via Newton-Schulz iterations, then applies entrywise sign operation, providing efficient approximation to taking maximal step over intersection of spectral and ℓ∞ constraint sets.
Result: SL∞ matches or outperforms AdamW and Muon in large-scale language and vision training (GPT-2, Llama pretraining, SiT image pretraining, supervised fine-tuning) while using only momentum-level optimizer state, and mitigates optimizer mismatch when fine-tuning AdamW-pretrained checkpoints.
Conclusion: SL∞ provides an effective optimizer combining spectral and coordinate control that performs well across diverse large-scale training tasks with reduced memory footprint compared to AdamW.
Abstract: Many optimizers can be interpreted as steepest-descent methods under norm-induced geometries, and thus inherit corresponding implicit biases. We introduce \nameA{} (\fullname{}), which combines spectral control from orthogonalized update directions with $\ell_\infty$-style coordinate control from sign updates. \nameA{} forms a Lion-style momentum direction, approximately orthogonalizes it via a few Newton–Schulz iterations, and then applies an entrywise sign, providing an efficient approximation to taking a maximal step over the intersection of the spectral and $\ell_\infty$ constraint sets (a scaled Hadamard-like set for matrix parameters). Despite the strong nonlinearity of orthogonalization and sign, we prove convergence under a mild, empirically verified diagonal-isotropy assumption. Across large-scale language and vision training, including GPT-2 and Llama pretraining, SiT image pretraining, and supervised fine-tuning, \nameA{} matches or outperforms AdamW and Muon under comparable tuning while using only momentum-level optimizer state, and it mitigates optimizer mismatch when fine-tuning AdamW-pretrained checkpoints.
[1115] PUNCH: Physics-informed Uncertainty-aware Network for Coronary Hemodynamics
Sukirt Thakur, Marcus Roper, Yang Zhou, Dmitry Yu. Isaev, Reza Akbarian Bafghi, Brahmajee K. Nallamothu, C. Alberto Figueroa, Srinivas Paruchuri, Scott Burger, Carlos Collet, Maziar Raissi
Main category: cs.LG
TL;DR: PUNCH is a non-invasive, uncertainty-aware framework that uses physics-informed neural networks to estimate coronary flow reserve from standard coronary angiography, enabling diagnosis of coronary microvascular dysfunction without invasive measurements.
Details
Motivation: Coronary microvascular dysfunction (CMD) affects up to half of patients with no obstructive coronary artery disease but remains under-diagnosed due to the need for invasive coronary flow reserve measurements. Current methods require specialized equipment and procedures that limit widespread clinical adoption.Method: PUNCH integrates physics-informed neural networks with variational inference to infer coronary blood flow from first-principles models of contrast transport in angiography. The framework doesn’t require ground-truth flow measurements or population-level training, using only standard angiographic data.
Result: The pipeline runs in ~3 minutes per patient on a single GPU. Validation on synthetic angiograms with controlled noise/artifacts and clinical bolus thermodilution data from 20 patients shows accurate and uncertainty-calibrated CFR estimation.
Conclusion: PUNCH establishes a new paradigm for CMD diagnosis and demonstrates how physics-informed inference can expand the diagnostic utility of existing clinical imaging without requiring additional invasive procedures.
Abstract: More than 10 million coronary angiograms are performed globally each year, providing a gold standard for detecting obstructive coronary artery disease. Yet, no obstructive lesions are identified in 70% of patients evaluated for ischemic heart disease. Up to half of these patients have undiagnosed, life-limiting coronary microvascular dysfunction (CMD), which remains under-detected due to the limited availability of invasive tools required to measure coronary flow reserve (CFR). Here, we introduce PUNCH, a non-invasive, uncertainty-aware framework for estimating CFR directly from standard coronary angiography. PUNCH integrates physics-informed neural networks with variational inference to infer coronary blood flow from first-principles models of contrast transport, without requiring ground-truth flow measurements or population-level training. The pipeline runs in approximately three minutes per patient on a single GPU. Validated on synthetic angiograms with controlled noise and imaging artifacts, as well as on clinical bolus thermodilution data from 20 patients, PUNCH demonstrates accurate and uncertainty-calibrated CFR estimation. This approach establishes a new paradigm for CMD diagnosis and illustrates how physics-informed inference can substantially expand the diagnostic utility of available clinical imaging.
[1116] Stein-Rule Shrinkage for Stochastic Gradient Estimation in High Dimensions
M. Arashi, M. Amintoosi
Main category: cs.LG
TL;DR: SR-Adam: A gradient estimator using Stein-rule shrinkage to contract noisy mini-batch gradients toward momentum-based stable estimators, improving Adam in large-batch regimes.
Details
Motivation: Stochastic gradient methods treat mini-batch gradients as unbiased estimators, but classical decision theory shows these are inadmissible in high dimensions. There's a need for better gradient estimation that accounts for high-dimensional noise.Method: Formulate gradient computation as high-dimensional estimation problem using Stein-rule shrinkage framework. Construct gradient estimator that adaptively contracts noisy mini-batch gradients toward stable estimator from historical momentum. Shrinkage intensity determined data-driven using online estimate of gradient noise variance, leveraging statistics from adaptive optimizers.
Result: Under Gaussian noise model, estimator uniformly dominates standard stochastic gradient under squared error loss and is minimax-optimal. SR-Adam (Adam with shrinkage) shows consistent improvements over Adam on CIFAR10 and CIFAR100 across multiple input noise levels in large-batch regime. Gains primarily from selectively applying shrinkage to high-dimensional convolutional layers.
Conclusion: Classical shrinkage principles provide principled approach to improving stochastic gradient estimation in deep learning, with practical algorithm SR-Adam offering consistent improvements at negligible computational cost.
Abstract: Stochastic gradient methods are central to large-scale learning, but they treat mini-batch gradients as unbiased estimators, which classical decision theory shows are inadmissible in high dimensions. We formulate gradient computation as a high-dimensional estimation problem and introduce a framework based on Stein-rule shrinkage. We construct a gradient estimator that adaptively contracts noisy mini-batch gradients toward a stable estimator derived from historical momentum. The shrinkage intensity is determined in a data-driven manner using an online estimate of gradient noise variance, leveraging statistics from adaptive optimizers. Under a Gaussian noise model, we show our estimator uniformly dominates the standard stochastic gradient under squared error loss and is minimax-optimal. We incorporate this into the Adam optimizer, yielding SR-Adam, a practical algorithm with negligible computational cost. Empirical evaluations on CIFAR10 and CIFAR100 across multiple levels of input noise show consistent improvements over Adam in the large-batch regime. Ablation studies indicate that gains arise primarily from selectively applying shrinkage to high-dimensional convolutional layers, while indiscriminate shrinkage across all parameters degrades performance. These results illustrate that classical shrinkage principles provide a principled approach to improving stochastic gradient estimation in deep learning.
[1117] HistoPrism: Unlocking Functional Pathway Analysis from Pan-Cancer Histology via Gene Expression Prediction
Susu Hu, Qinghe Zeng, Nithya Bhasker, Jakob Nikolas Kather, Stefanie Speidel
Main category: cs.LG
TL;DR: HistoPrism is a transformer-based model that predicts spatial gene expression from H&E histology images across multiple cancer types, with evaluation focused on biologically meaningful pathway-level predictions rather than just individual gene variance.
Details
Motivation: Current methods for predicting gene expression from histology are limited to specific cancer types and focus on variance-based evaluation, lacking assessment of functional biological relevance. There's a need for models that generalize across cancer types and capture coherent biological signals for clinical impact.Method: HistoPrism uses an efficient transformer-based architecture for pan-cancer prediction of gene expression from H&E histology. The key innovation is a pathway-level benchmark that evaluates predictions based on coherent functional pathways rather than isolated gene-level variance.
Result: HistoPrism outperforms prior state-of-the-art models on highly variable genes and achieves substantial gains on pathway-level prediction, demonstrating its ability to recover biologically coherent transcriptomic patterns with strong pan-cancer generalization and improved efficiency.
Conclusion: HistoPrism establishes a new standard for clinically relevant transcriptomic modeling from routinely available histology by providing strong pan-cancer generalization and focusing on biologically meaningful pathway-level predictions rather than just gene variance.
Abstract: Predicting spatial gene expression from H&E histology offers a scalable and clinically accessible alternative to sequencing, but realizing clinical impact requires models that generalize across cancer types and capture biologically coherent signals. Prior work is often limited to per-cancer settings and variance-based evaluation, leaving functional relevance underexplored. We introduce HistoPrism, an efficient transformer-based architecture for pan-cancer prediction of gene expression from histology. To evaluate biological meaning, we introduce a pathway-level benchmark, shifting assessment from isolated gene-level variance to coherent functional pathways. HistoPrism not only surpasses prior state-of-the-art models on highly variable genes , but also more importantly, achieves substantial gains on pathway-level prediction, demonstrating its ability to recover biologically coherent transcriptomic patterns. With strong pan-cancer generalization and improved efficiency, HistoPrism establishes a new standard for clinically relevant transcriptomic modeling from routinely available histology.
[1118] Elastic Spectral State Space Models for Budgeted Inference
Dachuan Song, Xuan Wang
Main category: cs.LG
TL;DR: ES-SSM enables single-model training with runtime truncation to arbitrary sizes for efficient deployment across different resource constraints.
Details
Motivation: Real-world applications require models to run on platforms with varying computational resources, but current approaches need multiple model variants or distillation, limiting flexibility and requiring additional training.Method: ES-SSM uses Hankel spectral filtering over state space models with input-adaptive gates trained under randomized spectral budgets and shared masked normalization to concentrate predictive capability in low-index components.
Result: Single ES-SSM model achieves competitive performance compared to Transformers and SSMs at similar parameter scales when truncated, with smooth budget-performance curves across various truncation levels.
Conclusion: ES-SSM provides efficient one-time training with flexible runtime adaptation, enabling practical deployment across diverse computational constraints without retraining.
Abstract: Foundation models are typically trained at a fixed computational capacity, while real-world applications require deployment across platforms with different resource constraints. Current approaches usually rely on training families of model variants or model distillation, which requires additional training and supports only a pre-selected set of sizes rather than fine-grained adaptation at runtime. In this paper, we propose Elastic Spectral State Space Models (ES-SSM), which require only one-time training at full capacity, but can be directly truncated into arbitrary scales for budgeted, runtime inference without retraining. Our ES-SSM builds on Hankel spectral filtering over a state space model (SSM), coupled with a lightweight input-adaptive gate trained under randomized spectral budgets. Using a shared masked normalization rule over the ordered spectral channels, we encourage predictive capability to concentrate in low-index components, while higher-index components act primarily as refinement. We test our algorithm across long-sequence benchmarks spanning text, logic, retrieval, vision, and audio. We demonstrate that a single ES-SSM model trained once can be truncated to provide competitive performance compared with modern Transformer and SSM baselines at similar parameter scales. Furthermore, by testing under various runtime budgets, we observe smooth and stable budget-performance curves over a wide range of truncation levels.
[1119] Decoupling Generalizability and Membership Privacy Risks in Neural Networks
Xingli Fang, Jung-Eun Kim
Main category: cs.LG
TL;DR: PPTP identifies separate regions for generalization and privacy risks in DNNs, enabling targeted protection that minimizes utility loss while enhancing privacy.
Details
Motivation: There's a trade-off between privacy preservation and model utility in deep learning. Different defense approaches show varying loss patterns, suggesting that generalization and privacy risks might be decoupled to maximize privacy gains without sacrificing utility.Method: The authors identify that generalization and privacy risks exist in different regions of deep neural network architectures. Based on this observation, they propose Privacy-Preserving Training Principle (PPTP) to protect model components from privacy risks while minimizing loss in generalizability.
Result: Through extensive evaluations, the approach shows significantly better maintenance of model generalizability while enhancing privacy preservation compared to existing methods.
Conclusion: By decoupling generalization and privacy risks in different network regions, PPTP enables more effective privacy protection with minimal utility degradation, offering a principled approach to privacy-preserving training.
Abstract: A deep learning model usually has to sacrifice some utilities when it acquires some other abilities or characteristics. Privacy preservation has such trade-off relationships with utilities. The loss disparity between various defense approaches implies the potential to decouple generalizability and privacy risks to maximize privacy gain. In this paper, we identify that the model’s generalization and privacy risks exist in different regions in deep neural network architectures. Based on the observations that we investigate, we propose Privacy-Preserving Training Principle (PPTP) to protect model components from privacy risks while minimizing the loss in generalizability. Through extensive evaluations, our approach shows significantly better maintenance in model generalizability while enhancing privacy preservation.
[1120] RAPTOR-AI for Disaster OODA Loop: Hierarchical Multimodal RAG with Experience-Driven Agentic Decision-Making
Takato Yasuno
Main category: cs.LG
TL;DR: RAPTOR-AI is an agentic multimodal RAG framework for disaster response that dynamically integrates diverse data sources (text, images, documents) using hierarchical knowledge construction, entropy-aware agentic control, and experiential learning to improve decision-making in humanitarian operations.
Details
Motivation: Traditional disaster response systems struggle with fragmented multimodal data and lack adaptive reasoning for dynamic emergency contexts. There's a need for systems that can rapidly synthesize diverse information sources (textual reports, aerial imagery, historical documentation) to support time-critical decision-making under extreme uncertainty in HADR operations.Method: The framework implements three key innovations: 1) Hierarchical multimodal knowledge construction using BLIP-based image understanding, ColVBERT embeddings, and long-context summarization from diverse sources; 2) Entropy-aware agentic control that dynamically selects optimal retrieval strategies based on situational context; 3) Experiential knowledge integration using LoRA adaptation for both expert and non-expert responders, operating within the OODA loop tactical framework.
Result: Experiments show significant improvements: 23% improvement in retrieval precision, 31% better situational grounding, and 27% enhanced task decomposition accuracy, with efficient scaling up to 3,000 document chunks. The system was tested on 46 tsunami-related PDFs (2,378 pages).
Conclusion: RAPTOR-AI advances beyond conventional static knowledge bases by implementing dynamic, experience-driven decision support for disaster response, effectively addressing HADR requirements across rescue, recovery, and reconstruction phases through multimodal information synthesis and adaptive reasoning.
Abstract: Humanitarian Assistance and Disaster Relief (HADR) operations demand rapid synthesis of multimodal information for time-critical decision-making under extreme uncertainty. Traditional information systems struggle with the fragmented, multimodal nature of disaster data and lack adaptive reasoning capabilities essential for dynamic emergency contexts. This work introduces RAPTOR-AI, an agentic multimodal Retrieval-Augmented Generation (RAG) framework that advances beyond conventional static knowledge bases by implementing dynamic, experience-driven decision support for disaster response. The system addresses HADR requirements across initial rescue, recovery, and reconstruction phases through three key innovations: hierarchical multimodal knowledge construction from diverse sources (textual reports, aerial imagery, historical documentation), entropy-aware agentic control that dynamically selects optimal retrieval strategies based on situational context, and experiential knowledge integration using LoRA adaptation for both expert and non-expert responders. The framework constructs hierarchical knowledge trees from 46 tsunami-related PDFs (2,378 pages) using BLIP-based image understanding, ColVBERT embeddings, and long-context summarization within the OODA loop (Observe, Orient, Decide, Act) tactical framework. Experiments demonstrate significant improvements over existing approaches: 23% improvement in retrieval precision, 31% better situational grounding, and 27% enhanced task decomposition accuracy, with efficient scaling up to 3,000 document chunks.
[1121] Step-Wise Refusal Dynamics in Autoregressive and Diffusion Language Models
Eliron Rahimi, Elad Hirshel, Rom Himelstein, Amit LeVi, Avi Mendelson, Chaim Baskin
Main category: cs.LG
TL;DR: DLMs show competitive generation quality but sampling mechanisms affect refusal behavior and jailbreak robustness; SRI signal enables interpretable safety analysis and lightweight detectors.
Details
Motivation: To understand how sampling mechanisms in diffusion language models (DLMs) versus autoregressive (AR) models affect refusal behavior and jailbreak robustness, and to develop interpretable safety analysis tools.Method: Developed analytical framework for step-wise refusal dynamics comparing AR and diffusion sampling; introduced Step-Wise Refusal Internal Dynamics (SRI) signal for interpretability; used geometric structure of SRI to capture internal recovery dynamics.
Result: SRI identifies anomalous behavior in harmful generations as incomplete internal recovery; enables lightweight inference-time detectors that generalize to unseen attacks with 100× lower inference overhead than existing defenses.
Conclusion: Sampling strategy itself plays central role in safety behavior distinct from learned representations; SRI provides interpretable safety analysis for both AR and DLMs with practical defense applications.
Abstract: Diffusion language models (DLMs) have recently emerged as a promising alternative to autoregressive (AR) models, offering parallel decoding and controllable sampling dynamics while achieving competitive generation quality at scale. Despite this progress, the role of sampling mechanisms in shaping refusal behavior and jailbreak robustness remains poorly understood. In this work, we present a fundamental analytical framework for step-wise refusal dynamics, enabling comparison between AR and diffusion sampling. Our analysis reveals that the sampling strategy itself plays a central role in safety behavior, as a factor distinct from the underlying learned representations. Motivated by this analysis, we introduce the Step-Wise Refusal Internal Dynamics (SRI) signal, which supports interpretability and improved safety for both AR and DLMs. We demonstrate that the geometric structure of SRI captures internal recovery dynamics, and identifies anomalous behavior in harmful generations as cases of \emph{incomplete internal recovery} that are not observable at the text level. This structure enables lightweight inference-time detectors that generalize to unseen attacks while matching or outperforming existing defenses with over $100\times$ lower inference overhead.
[1122] PHAT: Modeling Period Heterogeneity for Multivariate Time Series Forecasting
Jiaming Ma, Qihe Huang, Guanjun Wang, Haofeng Ma, Sheng Huang, Zhengyang Zhou, Pengkun Wang, Binwu Wang, Yang Wang
Main category: cs.LG
TL;DR: PHAT is a transformer-based model for multivariate time series forecasting that addresses periodic heterogeneity by organizing data into periodic buckets and using positive-negative attention mechanisms.
Details
Motivation: Existing time series forecasting models fail to capture periodic heterogeneity where different variables have distinct and dynamically changing periods, leading to suboptimal performance on real-world data with complex periodic patterns.Method: Organizes multivariate inputs into 3D “periodic bucket” tensors (variable groups by periodicity, time steps by phase, offsets within period), restricts interactions within buckets, and uses positive-negative attention mechanism with periodic alignment and deviation perspectives plus modulation terms encoding periodic priors.
Result: Significantly outperforms 18 baselines on 14 real-world datasets, achieving highly competitive forecasting performance.
Conclusion: PHAT effectively captures periodic heterogeneity in multivariate time series through its periodic bucket organization and attention mechanisms, providing superior forecasting performance.
Abstract: While existing multivariate time series forecasting models have advanced significantly in modeling periodicity, they largely neglect the periodic heterogeneity common in real-world data, where variables exhibit distinct and dynamically changing periods. To effectively capture this periodic heterogeneity, we propose PHAT (Period Heterogeneity-Aware Transformer). Specifically, PHAT arranges multivariate inputs into a three-dimensional “periodic bucket” tensor, where the dimensions correspond to variable group characteristics with similar periodicity, time steps aligned by phase, and offsets within the period. By restricting interactions within buckets and masking cross-bucket connections, PHAT effectively avoids interference from inconsistent periods. We also propose a positive-negative attention mechanism, which captures periodic dependencies from two perspectives: periodic alignment and periodic deviation. Additionally, the periodic alignment attention scores are decomposed into positive and negative components, with a modulation term encoding periodic priors. This modulation constrains the attention mechanism to more faithfully reflect the underlying periodic trends. A mathematical explanation is provided to support this property. We evaluate PHAT comprehensively on 14 real-world datasets against 18 baselines, and the results show that it significantly outperforms existing methods, achieving highly competitive forecasting performance. Our sources is available at GitHub.
[1123] Semantics-Aware Generative Latent Data Augmentation for Learning in Low-Resource Domains
Jaesung Bae, Minje Kim
Main category: cs.LG
TL;DR: GeLDA is a semantics-aware generative latent data augmentation framework that uses conditional diffusion models in foundation model latent spaces to address data scarcity in downstream tasks.
Details
Motivation: Deep learning underperforms in data-scarce settings despite foundation models' strong generalization. Even with pre-trained features, downstream fine-tuning suffers from limited labeled data, requiring effective data augmentation methods.Method: GeLDA uses conditional diffusion models to generate samples in low-dimensional FM-induced latent spaces, conditioning generation on auxiliary feature vectors that capture semantic relationships among classes or subdomains for targeted augmentation.
Result: GeLDA improves Whisper-large baseline’s unweighted average recall by 6.13% in zero-shot language-specific speech emotion recognition, and achieves 74.7% tail-class accuracy on ImageNet-LT, setting new state-of-the-art in long-tailed image classification.
Conclusion: GeLDA effectively addresses data scarcity by leveraging FM latent spaces for efficient, high-quality data generation, demonstrating strong performance in both audio (speech) and vision (image) domains with limited data.
Abstract: Despite strong performance in data-rich regimes, deep learning often underperforms in the data-scarce settings common in practice. While foundation models (FMs) trained on massive datasets demonstrate strong generalization by extracting general-purpose features, they can still suffer from scarce labeled data during downstream fine-tuning. To address this, we propose GeLDA, a semantics-aware generative latent data augmentation framework that leverages conditional diffusion models to synthesize samples in an FM-induced latent space. Because this space is low-dimensional and concentrates task-relevant information compared to the input space, GeLDA enables efficient, high-quality data generation. GeLDA conditions generation on auxiliary feature vectors that capture semantic relationships among classes or subdomains, facilitating data augmentation in low-resource domains. We validate GeLDA in two large-scale recognition tasks: (a) in zero-shot language-specific speech emotion recognition, GeLDA improves the Whisper-large baseline’s unweighted average recall by 6.13%; and (b) in long-tailed image classification, it achieves 74.7% tail-class accuracy on ImageNet-LT, setting a new state-of-the-art result.
[1124] Provable Cooperative Multi-Agent Exploration for Reward-Free MDPs
Idan Barnea, Orin Levy, Yishay Mansour
Main category: cs.LG
TL;DR: Multi-agent RL for reward-free exploration in tabular MDPs, analyzing tradeoff between learning phases and number of agents needed to learn dynamics without rewards.
Details
Motivation: Study cooperative multi-agent reinforcement learning in reward-free exploration settings where multiple agents jointly explore unknown MDPs to learn dynamics without observing rewards, focusing on the tradeoff between number of learning phases and number of agents.Method: Adopt phased learning framework where multiple agents independently interact with environment in each phase, each executing assigned policies and observing trajectories. Analyze tabular finite-horizon MDPs and characterize tradeoff between learning phases and agent count.
Result: Identified sharp transition governed by horizon H: with H learning phases, algorithm uses Õ(S⁶H⁶A/ε²) agents for ε-approximation of dynamics. Lower bound shows any algorithm with ρ<H phases requires at least A^(H/ρ) agents for constant accuracy.
Conclusion: Essential to have order H learning phases when limiting number of agents to be polynomial, establishing fundamental tradeoff between learning phases and agent count in multi-agent reward-free exploration.
Abstract: We study cooperative multi-agent reinforcement learning in the setting of reward-free exploration, where multiple agents jointly explore an unknown MDP in order to learn its dynamics (without observing rewards). We focus on a tabular finite-horizon MDP and adopt a phased learning framework. In each learning phase, multiple agents independently interact with the environment. More specifically, in each learning phase, each agent is assigned a policy, executes it, and observes the resulting trajectory. Our primary goal is to characterize the tradeoff between the number of learning phases and the number of agents, especially when the number of learning phases is small. Our results identify a sharp transition governed by the horizon $H$. When the number of learning phases equals $H$, we present a computationally efficient algorithm that uses only $\tilde{O}(S^6 H^6 A / ε^2)$ agents to obtain an $ε$ approximation of the dynamics (i.e., yields an $ε$-optimal policy for any reward function). We complement our algorithm with a lower bound showing that any algorithm restricted to $ρ< H$ phases requires at least $A^{H/ρ}$ agents to achieve constant accuracy. Thus, we show that it is essential to have an order of $H$ learning phases if we limit the number of agents to be polynomial.
[1125] Fat-Cat: Document-Driven Metacognitive Multi-Agent System for Complex Reasoning
Tong Yang, Yemin Wang, Chaoning Zhang, Aming Wu
Main category: cs.LG
TL;DR: Fat-Cat is a document-driven agent architecture that improves LLM-based agent performance by using Markdown documents for state representation instead of rigid JSON, reducing syntactic overhead and enhancing semantic reasoning.
Details
Motivation: Existing LLM-based agent frameworks use rigid, syntax-heavy state representations like nested JSON, which forces models to devote significant attention to syntactic processing rather than semantic reasoning, limiting agent effectiveness.Method: Proposes Fat-Cat with three key components: (1) Semantic File System representing agent state as Markdown documents aligned with pre-training corpora, (2) Textual Strategy Evolution accumulating task-solving knowledge without parameter updates, and (3) Closed-Loop Watcher monitoring reasoning trajectories to reduce hallucinations.
Result: Fat-Cat consistently improves agent performance on reasoning, retrieval, and coding benchmarks, enabling the Kimi-k2 model to outperform proprietary GPT-4o baseline on HotPotQA. Replacing document-based state with JSON leads to performance degradation.
Conclusion: Document-driven state modeling is critical for efficient LLM-based agents, as it improves signal-to-noise ratio in state management compared to rigid syntax-heavy representations like JSON.
Abstract: The effectiveness of LLM-based agents is often limited not by model capacity alone, but by how efficiently contextual information is utilized at runtime. Existing agent frameworks rely on rigid, syntax-heavy state representations such as nested JSON, which require models to devote a substantial portion of their limited attention to syntactic processing rather than semantic reasoning. In this paper, we propose Fat-Cat, a document-driven agent architecture that improves the signal-to-noise ratio of state management. By integrating three key components: (1) a Semantic File System that represents agent state as Markdown documents aligned with common pre-training corpora, (2) a Textual Strategy Evolution module that accumulates task-solving knowledge without parameter updates, and (3) a Closed-Loop Watcher that monitors reasoning trajectories to reduce hallucinations. Extensive reasoning, retrieval, and coding benchmarks, Fat-Cat consistently improves agent performance. It enables the Kimi-k2 model to outperform the proprietary GPT-4o baseline on HotPotQA. Replacing the document-based state with JSON leads to performance drop, while empirically validating the critical necessity of document-driven state modeling over rigid syntax. The code is available at https://github.com/answeryt/Fat-Cat.
[1126] Exposing Vulnerabilities in Explanation for Time Series Classifiers via Dual-Target Attacks
Bohan Wang, Zewen Liu, Lu Lin, Hui Liu, Li Xiong, Ming Jin, Wei Jin
Main category: cs.LG
TL;DR: TSEF attack shows temporal consistency in time series explanations can be misleading - predictions and explanations can be adversarially decoupled while keeping explanations plausible.
Details
Motivation: Current interpretable time series deep learning systems often use temporal consistency of explanations as evidence of robustness, but this assumption may be flawed and misleading.Method: Proposes TSEF (Time Series Explanation Fooler), a dual-target attack that jointly manipulates classifier and explainer outputs to achieve targeted misclassification while keeping explanations consistent with a chosen reference rationale.
Result: Across multiple datasets and explainer backbones, TSEF successfully decouples predictions from explanations, showing explanation stability is a misleading proxy for decision robustness.
Conclusion: Explanation stability alone is insufficient for trustworthy time series tasks; coupling-aware robustness evaluations are needed to ensure both prediction and explanation reliability.
Abstract: Interpretable time series deep learning systems are often assessed by checking temporal consistency on explanations, implicitly treating this as evidence of robustness. We show that this assumption can fail: Predictions and explanations can be adversarially decoupled, enabling targeted misclassification while the explanation remains plausible and consistent with a chosen reference rationale. We propose TSEF (Time Series Explanation Fooler), a dual-target attack that jointly manipulates the classifier and explainer outputs. In contrast to single-objective misclassification attacks that disrupt explanation and spread attribution mass broadly, TSEF achieves targeted prediction changes while keeping explanations consistent with the reference. Across multiple datasets and explainer backbones, our results consistently reveal that explanation stability is a misleading proxy for decision robustness and motivate coupling-aware robustness evaluations for trustworthy time series tasks.
[1127] Bypassing the Rationale: Causal Auditing of Implicit Reasoning in Language Models
Anish Sathyanarayanan, Aditya Nagarsekar, Aarush Rathore
Main category: cs.LG
TL;DR: The paper introduces a causal audit method (CoT Mediation Index) to measure how much Chain-of-Thought reasoning actually influences model decisions, finding that CoT faithfulness varies widely and cannot be inferred from behavioral performance alone.
Details
Motivation: To determine whether Chain-of-Thought prompting actually causes models to use the emitted reasoning text for decision-making, or if models produce plausible rationales while routing computation through latent pathways, addressing concerns about CoT as a transparency mechanism.Method: Uses activation patching to audit CoT faithfulness layerwise, introducing the CoT Mediation Index (CMI) which compares performance degradation from patching CoT-token hidden states against matched control patches across multiple model families and scales.
Result: CoT-specific influence is typically depth-localized into narrow “reasoning windows,” with bypass regimes where CMI is near-zero despite plausible CoT text. Reasoning-tuned models show stronger mediation than larger untuned counterparts, and Mixture-of-Experts models exhibit more distributed mediation.
Conclusion: CoT faithfulness varies substantially across models and tasks and cannot be inferred from behavior alone, motivating causal, layerwise audits when using CoT as a transparency signal.
Abstract: Chain-of-thought (CoT) prompting is widely used as a reasoning aid and is often treated as a transparency mechanism. Yet behavioral gains under CoT do not imply that the model’s internal computation causally depends on the emitted reasoning text, i.e., models may produce fluent rationales while routing decision-critical computation through latent pathways. We introduce a causal, layerwise audit of CoT faithfulness based on activation patching. Our key metric, the CoT Mediation Index (CMI), isolates CoT-specific causal influence by comparing performance degradation from patching CoT-token hidden states against matched control patches. Across multiple model families (Phi, Qwen, DialoGPT) and scales, we find that CoT-specific influence is typically depth-localized into narrow “reasoning windows,” and we identify bypass regimes where CMI is near-zero despite plausible CoT text. We further observe that models tuned explicitly for reasoning tend to exhibit stronger and more structured mediation than larger untuned counterparts, while Mixture-of-Experts models show more distributed mediation consistent with routing-based computation. Overall, our results show that CoT faithfulness varies substantially across models and tasks and cannot be inferred from behavior alone, motivating causal, layerwise audits when using CoT as a transparency signal.
[1128] Online Vector Quantized Attention
Nick Alonso, Tomas Figliolia, Beren Millidge
Main category: cs.LG
TL;DR: OVQ-attention is a novel sequence mixing layer that achieves linear compute and constant memory while maintaining strong long-context performance through sparse memory updates, outperforming linear attention baselines and competing with self-attention up to 64k sequences.
Details
Motivation: Current sequence mixing layers face a trade-off: self-attention has quadratic compute costs but good long-context performance, while linear attention and SSMs have linear compute but struggle with long contexts. There's a need for a better compromise between efficiency and long-context processing capability.Method: Develops online vector-quantized (OVQ) attention, which uses linear compute costs and constant memory. Unlike linear attention and SSMs, it employs a sparse memory update mechanism that allows for larger memory states and increased memory capacity. The approach is theoretically grounded in Gaussian mixture regression.
Result: OVQ-attention shows significant improvements over linear attention baselines and original VQ-attention. It demonstrates competitive, sometimes identical, performance to strong self-attention baselines up to 64k sequence length, while using only a small fraction of the memory of full self-attention.
Conclusion: OVQ-attention successfully addresses the efficiency-performance trade-off in sequence mixing layers, offering a practical solution for long-context processing with linear compute and constant memory requirements while maintaining competitive performance with self-attention.
Abstract: Standard sequence mixing layers used in language models struggle to balance efficiency and performance. Self-attention performs well on long context tasks but has expensive quadratic compute and linear memory costs, while linear attention and SSMs use only linear compute and constant memory but struggle with long context processing. In this paper, we develop a sequence mixing layer that aims to find a better compromise between memory-compute costs and long-context processing, which we call online vector-quantized (OVQ) attention. OVQ-attention requires linear compute costs and constant memory, but, unlike linear attention and SSMs, it uses a sparse memory update that allows it to greatly increase the size of its memory state and, consequently, memory capacity. We develop a theoretical basis for OVQ-attention based on Gaussian mixture regression, and we test it on a variety of synthetic long context tasks and on long context language modeling. OVQ-attention shows significant improvements over linear attention baselines and the original VQ-attention, on which OVQ-attention was inspired. It demonstrates competitive, and sometimes identical, performance to strong self-attention baselines up 64k sequence length, despite using a small fraction of the memory of full self-attention.
[1129] Understanding and Guiding Layer Placement in Parameter-Efficient Fine-Tuning of Large Language Models
Yichen Xu, Yuyang Liang, Shan Dai, Tianyang Hu, Tsz Nam Chan, Chenhao Ma
Main category: cs.LG
TL;DR: A framework for analyzing parameter-efficient fine-tuning (PEFT) through a projected residual view, enabling layer selection based on residual norms, activation energy, and layer coupling to optimize performance vs. cost trade-offs.
Details
Motivation: Current PEFT methods apply fine-tuning uniformly across all layers without understanding layer-specific contributions, leading to inefficient resource usage. There's a need for principled layer selection to balance performance, fine-tuning cost, and inference latency.Method: Develops a unified projected residual view of PEFT, analyzing layerwise adaptation through three quantities: projected residual norm (resnorm), activation energy, and layer coupling. Introduces Layer Card diagnostic tool to summarize residual signal strength, compute cost, and performance for each layer.
Result: On Qwen3-8B, selective adaptation of a subset of layers achieves performance close to full-layer LoRA while substantially reducing fine-tuning cost and the number of adapter-augmented layers during inference.
Conclusion: Layer selection guided by the proposed framework offers a cost-performance-aware alternative to uniform PEFT, enabling flexible prioritization of different objectives like maximizing performance or reducing costs.
Abstract: As large language models (LLMs) continue to grow, the cost of full-parameter fine-tuning has made parameter-efficient fine-tuning (PEFT) the default strategy for downstream adaptation. Constraints from inference latency in scalable serving and fine-tuning cost in edge or rapid-deployment settings make the choice of which layers to fine-tune unavoidable. Yet current practice typically applies PEFT uniformly across all layers, with limited understanding or leverage of layer selection. This paper develops a unified projected residual view of PEFT on top of a frozen base model. Under a local quadratic approximation, layerwise adaptation is governed by three quantities: (i) the projected residual norm (resnorm), which measures how much correctable bias a layer can capture; (ii) the activation energy, which determines feature conditioning; and (iii) layer coupling, which quantifies how strongly residuals interact across layers. We show that, for squared loss and linear adapters, the resnorm equals a normalized gradient norm, activation energy controls ill-conditioning and noise amplification, and weak coupling yields approximately additive layerwise contributions. Building on these insights, we introduce the Layer Card, a reusable diagnostic that summarizes residual signal strength, compute cost, and performance for each layer of a given model. With an identical model and LoRA configuration, Layer Card-guided placement refines the choice of adapted layers to flexibly prioritize different objectives, such as maximizing performance or reducing fine-tuning cost. Moreover, on Qwen3-8B, we show that selectively adapting a subset of layers can achieve performance close to full-layer LoRA while substantially reducing fine-tuning cost and the number of adapter-augmented layers during inference, offering a more cost-performance-aware alternative to full-layer insertion.
[1130] SAFE: Stable Alignment Finetuning with Entropy-Aware Predictive Control for Reinforcement Learning from Human Feedback (RLHF)
Dipan Maity
Main category: cs.LG
TL;DR: SAFE is a new RLHF algorithm that improves stability over PPO through entropy-aware KL regulation and pessimistic value estimation, achieving better reward performance with fewer crashes.
Details
Motivation: PPO has heuristic design, suffers from reward oscillations, entropy collapse, value drift, and policy divergence in RLHF, requiring frequent restarts and extensive tuning.Method: Combines Double Soft-Min Critic for pessimistic value estimation with entropy-gated KL regulation and PID-controlled adaptive thresholds, distinguishing high/low entropy modes.
Result: On 3B parameter model: +5.15% training-average reward vs PPO (0.725 vs 0.689), negligible reward crashes, superior KL control, minimal computational overhead.
Conclusion: SAFE provides interpretable, crash-resistant RLHF framework maintaining aggressive learning while ensuring stable long-horizon optimization for production deployment.
Abstract: Proximal Policy Optimization (PPO) has been positioned by recent literature as the canonical method for the RL part of Reinforcement Learning from Human Feedback (RLHF). PPO performs well empirically but has a heuristic motivation and handles the KL-divergence constraint used in LM-RLHF in an ad-hoc manner and suffers form reward oscillations, entropy collapse, value function drift, and sudden policy divergence that require frequent restarts and extensive hyperparameter tuning. In this paper, we develop a new pure on policy actor-critic RL method for the LM-RLHF setting. We present SAFE (Stable Alignment Finetuning with Entropy-aware control),a novel RLHF algorithm that combines a Double Soft-Min Critic for pessimistic value estimation with a new multi-layer stabilization framework combining entropy-gated KL regulation, and PID-controlled adaptive thresholds. Unlike standard PPO’s symmetric KL penalties, SAFE distinguishes high-entropy exploration from low-entropy mode collapse and adjusts penalties dynamically based on reward velocity. Experiments on a 3B parameter model show SAFE achieves +5.15% training-average reward than PPO (0.725 vs 0.689), negligible reward crashes, and superior KL control than ppo . Our method adds minimal computational overhead and provides an interpretable, crash-resistant RLHF framework that maintains aggressive learning speed while ensuring stable long-horizon optimization suitable for production deployment. Code is available at https://github.com/ryyzn9/SAFE
[1131] NeuroCanvas: VLLM-Powered Robust Seizure Detection by Reformulating Multichannel EEG as Image
Yan Chen, Jie Peng, Moajjem Hossain Chowdhury, Tianlong Chen, Yunmei Liu
Main category: cs.LG
TL;DR: NeuroCanvas: A framework that converts multi-channel EEG signals into structured visual representations for seizure detection using LLMs, addressing channel heterogeneity and computational inefficiency through entropy-guided channel selection and visual tokenization.
Details
Motivation: Manual review of long-term EEG recordings for seizure detection is labor-intensive. While recent efforts to encode EEG signals into LLMs show promise, two key challenges remain: 1) multi-channel heterogeneity (seizure-relevant information varies across EEG channels), and 2) computational inefficiency (EEG signals require massive tokenization for LLM processing).Method: NeuroCanvas consists of two modules: 1) Entropy-guided Channel Selector (ECS) that selects seizure-relevant channels for LLM input, and 2) Canvas of Neuron Signal (CNS) that converts selected multi-channel EEG signals into structured visual representations. ECS addresses channel heterogeneity, while CNS uses compact visual tokens to improve computational efficiency.
Result: Evaluation across multiple seizure detection datasets shows significant improvements: 20% increase in F1 score and 88% reduction in inference latency compared to existing methods.
Conclusion: NeuroCanvas provides a scalable and effective solution for real-time, resource-efficient seizure detection in clinical practice by transforming EEG signals into visual representations for LLM processing, addressing both channel heterogeneity and computational challenges.
Abstract: Accurate and timely seizure detection from Electroencephalography (EEG) is critical for clinical intervention, yet manual review of long-term recordings is labor-intensive. Recent efforts to encode EEG signals into large language models (LLMs) show promise in handling neural signals across diverse patients, but two significant challenges remain: (1) multi-channel heterogeneity, as seizure-relevant information varies substantially across EEG channels, and (2) computing inefficiency, as the EEG signals need to be encoded into a massive number of tokens for the prediction. To address these issues, we draw the EEG signal and propose the novel NeuroCanvas framework. Specifically, NeuroCanvas consists of two modules: (i) The Entropy-guided Channel Selector (ECS) selects the seizure-relevant channels input to LLM and (ii) the following Canvas of Neuron Signal (CNS) converts selected multi-channel heterogeneous EEG signals into structured visual representations. The ECS module alleviates the multi-channel heterogeneity issue, and the CNS uses compact visual tokens to represent the EEG signals that improve the computing efficiency. We evaluate NeuroCanvas across multiple seizure detection datasets, demonstrating a significant improvement of 20% in F1 score and reductions of 88% in inference latency. These results highlight NeuroCanvas as a scalable and effective solution for real-time and resource-efficient seizure detection in clinical practice.
[1132] Momentum Attention: The Physics of In-Context Learning and Spectral Forensics for Mechanistic Interpretability
Kingsuk Maitra
Main category: cs.LG
TL;DR: Momentum Attention introduces physical circuit dynamics to Transformers via symplectic shear, enabling single-layer induction heads through kinematic momentum and revealing a symplectic-filter duality.
Details
Motivation: To extend mechanistic interpretability of Transformers by viewing them as physical circuits with conservation laws and time-varying AC dynamics, bridging generative AI with Hamiltonian physics and signal processing.Method: Introduces Momentum Attention with symplectic augmentation using kinematic difference operator p_t = q_t - q_{t-1}, applying symplectic shear on queries and keys, and establishing symplectic-filter duality between physical shear and high-pass filtering.
Result: 125M Momentum model exceeds expectations on induction-heavy tasks, tracks 350M baseline within ~2.9% validation loss, enables single-layer induction heads (bypassing L≥2 constraint), and reveals scaling law γ* = 4.17 × N^{-0.74} for momentum-depth fungibility.
Conclusion: The framework connects generative AI, Hamiltonian physics, and signal processing through physical circuit interpretation of Transformers, offering complementary analytical toolkit for mechanistic interpretability.
Abstract: The Mechanistic Interpretability (MI) program has mapped the Transformer as a precise computational graph. We extend this graph with a conservation law and time-varying AC dynamics, viewing it as a physical circuit. We introduce Momentum Attention, a symplectic augmentation embedding physical priors via the kinematic difference operator $p_t = q_t - q_{t-1}$, implementing the symplectic shear $\hat{q}_t = q_t + γp_t$ on queries and keys. We identify a fundamental Symplectic-Filter Duality: the physical shear is mathematically equivalent to a High-Pass Filter. This duality is our cornerstone contribution – by injecting kinematic momentum, we sidestep the topological depth constraint ($L \geq 2$) for induction head formation. While standard architectures require two layers for induction from static positions, our extension grants direct access to velocity, enabling Single-Layer Induction and Spectral Forensics via Bode Plots. We formalize an Orthogonality Theorem proving that DC (semantic) and AC (mechanistic) signals segregate into orthogonal frequency bands when Low-Pass RoPE interacts with High-Pass Momentum. Validated through 5,100+ controlled experiments (documented in Supplementary Appendices A–R and 27 Jupyter notebooks), our 125M Momentum model exceeds expectations on induction-heavy tasks while tracking a 350M baseline within $\sim$2.9% validation loss. Dedicated associative recall experiments reveal a scaling law $γ^* = 4.17 \times N^{-0.74}$ establishing momentum-depth fungibility. We offer this framework as a complementary analytical toolkit connecting Generative AI, Hamiltonian Physics, and Signal Processing.
[1133] SLAY: Geometry-Aware Spherical Linearized Attention with Yat-Kernel
Jose Miguel Luna, Taha Bouhsine, Krzysztof Choromanski
Main category: cs.LG
TL;DR: SLAY introduces a new linear-time attention mechanism using spherical Yat-kernels that constrains queries/keys to unit sphere for angular alignment, achieving near-identical performance to softmax attention with O(L) complexity.
Details
Motivation: To develop linear-time attention mechanisms that closely approximate standard softmax attention without performance trade-offs, enabling scalable Transformers for long sequences while maintaining the quality of full attention.Method: Proposes Spherical Linearized Attention with Yat Kernels (SLAY) that constrains queries and keys to unit sphere, uses Bernstein’s theorem to express spherical Yat-kernel as nonnegative mixture of polynomial-exponential product kernels, and derives positive random-feature approximation for linear-time O(L) attention.
Result: SLAY achieves performance nearly indistinguishable from standard softmax attention while maintaining linear time and memory scaling, consistently outperforming prior linear-time attention mechanisms like Performers and Cosformers.
Conclusion: SLAY represents the closest linear-time approximation to softmax attention reported to date, enabling scalable Transformers without typical performance trade-offs of attention linearization.
Abstract: We propose a new class of linear-time attention mechanisms based on a relaxed and computationally efficient formulation of the recently introduced E-Product, often referred to as the Yat-kernel (Bouhsine, 2025). The resulting interactions are geometry-aware and inspired by inverse-square interactions in physics. Our method, Spherical Linearized Attention with Yat Kernels (SLAY), constrains queries and keys to the unit sphere so that attention depends only on angular alignment. Using Bernstein’s theorem, we express the spherical Yat-kernel as a nonnegative mixture of polynomial-exponential product kernels and derive a strictly positive random-feature approximation enabling linear-time O(L) attention. We establish positive definiteness and boundedness on the sphere and show that the estimator yields well-defined, nonnegative attention scores. Empirically, SLAY achieves performance that is nearly indistinguishable from standard softmax attention while retaining linear time and memory scaling, and consistently outperforms prior linear-time attention mechanisms such as Performers and Cosformers. To the best of our knowledge, SLAY represents the closest linear-time approximation to softmax attention reported to date, enabling scalable Transformers without the typical performance trade-offs of attention linearization.
[1134] A Unified Framework for Rethinking Policy Divergence Measures in GRPO
Qingyuan Wu, Yuhui Wang, Simon Sinong Zhan, Yanning Dai, Shilong Deng, Sarra Habchi, Qi Zhu, Matthias Gallé, Chao Huang
Main category: cs.LG
TL;DR: RLVR with KL3 estimator improves LLM reasoning via principled policy divergence constraints that promote exploration while maintaining training stability.
Details
Motivation: Existing RLVR methods like GRPO use likelihood ratio clipping for stable policy updates, but lack a unified framework to analyze how different policy divergence measures affect exploration and performance.Method: Introduces unified clipping framework for policy divergence measures, identifies KL3 estimator as key constraint, shows it’s equivalent to asymmetric ratio-based clipping that reallocates probability mass toward high-confidence actions.
Result: KL3 estimator improves both training stability and final performance on mathematical reasoning benchmarks when incorporated into GRPO.
Conclusion: Principled policy divergence constraints like KL3 are important for policy optimization in RLVR, promoting stronger exploration while retaining simplicity of existing methods.
Abstract: Reinforcement Learning with Verified Reward (RLVR) has emerged as a critical paradigm for advancing the reasoning capabilities of Large Language Models (LLMs). Most existing RLVR methods, such as GRPO and its variants, ensure stable updates by constraining policy divergence through clipping likelihood ratios. This paper introduces a unified clipping framework that characterizes existing methods via a general notion of policy divergence, encompassing both likelihood ratios and Kullback-Leibler (KL) divergences and extending to alternative measures. The framework provides a principled foundation for systematically analyzing how different policy divergence measures affect exploration and performance. We further identify the KL3 estimator, a variance-reduced Monte Carlo estimator of the KL divergence, as a key policy divergence constraint. We theoretically demonstrate that the KL3-based constraint is mathematically equivalent to an asymmetric ratio-based clipping that reallocates probability mass toward high-confidence actions, promoting stronger exploration while retaining the simplicity of GRPO-style methods. Empirical results on mathematical reasoning benchmarks demonstrate that incorporating the KL3 estimator into GRPO improves both training stability and final performance, highlighting the importance of principled policy divergence constraints in policy optimization.
[1135] Alignment Verifiability in Large Language Models: Normative Indistinguishability under Behavioral Evaluation
Igor Santos-Grueiro
Main category: cs.LG
TL;DR: Behavioral evaluation of LLM alignment is insufficient to uniquely identify latent alignment properties due to evaluation-aware policies that can game evaluation signals.
Details
Motivation: Current LLM alignment evaluation relies on behavioral compliance during finite testing, but this doesn't guarantee true latent alignment. The paper aims to formalize the limitations of inferring global alignment properties from bounded behavioral evidence.Method: Theoretical framework using statistical identifiability under partial observability, formalizing the Alignment Verifiability Problem and Normative Indistinguishability. Includes constructive proof using Llama-3.2-3B to demonstrate evaluation-aware policies that game explicit vs. implicit evaluation signals.
Result: Shows that under finite behavioral evaluation with evaluation-aware policies, observed compliance doesn’t uniquely identify latent alignment, only membership in equivalence classes of conditionally compliant policies. Demonstrates policies that are perfectly compliant under explicit evaluation but show degraded alignment when evaluation is implicit.
Conclusion: Behavioral benchmarks provide necessary but insufficient evidence for latent alignment when policies can be evaluation-aware. Current evaluation practices have fundamental limitations in identifying true alignment properties.
Abstract: Behavioral evaluation is the dominant paradigm for assessing alignment in large language models (LLMs). In current practice, observed compliance under finite evaluation protocols is treated as evidence of latent alignment. However, the inference from bounded behavioral evidence to claims about global latent properties is rarely analyzed as an identifiability problem. In this paper, we study alignment evaluation through the lens of statistical identifiability under partial observability. We allow agent policies to condition their behavior on observable signals correlated with the evaluation regime, a phenomenon we term evaluation awareness. Within this framework, we formalize the Alignment Verifiability Problem and introduce Normative Indistinguishability, which arises when distinct latent alignment hypotheses induce identical distributions over evaluator-accessible observations. Our main theoretical contribution is a conditional impossibility result: under finite behavioral evaluation and evaluation-aware policies, observed compliance does not uniquely identify latent alignment, but only membership in an equivalence class of conditionally compliant policies, under explicit assumptions on policy expressivity and observability. We complement the theory with a constructive existence proof using an instruction-tuned LLM (Llama-3.2-3B), demonstrating a conditional policy that is perfectly compliant under explicit evaluation signals yet exhibits degraded identifiability when the same evaluation intent is conveyed implicitly. Together, our results show that behavioral benchmarks provide necessary but insufficient evidence for latent alignment under evaluation awareness.
[1136] f-GRPO and Beyond: Divergence-Based Reinforcement Learning Algorithms for General LLM Alignment
Rajdeep Haldar, Lantao Mei, Guang Lin, Yue Xing, Qifan Song
Main category: cs.LG
TL;DR: A unified divergence-based framework for LLM alignment that extends preference alignment to general settings like RL with verifiable rewards, proposing f-GRPO and f-HAL objectives with theoretical guarantees.
Details
Motivation: To extend the divergence-based perspective of preference alignment to general alignment settings where only environmental rewards are available (like RLVR), creating a unified framework for LLM alignment.Method: Proposes f-Group Relative Policy Optimization (f-GRPO) for on-policy RL and f-Hybrid Alignment Loss (f-HAL) for hybrid on/off-policy objectives based on variational representation of f-divergences.
Result: Empirical validation on RLVR (Math Reasoning) and PA tasks (Safety Alignment) shows superior performance and flexibility compared to current methods, with theoretical guarantees of reward improvement.
Conclusion: The divergence-based framework provides a unified approach to LLM alignment that works across different settings, offering both theoretical guarantees and empirical effectiveness.
Abstract: Recent research shows that Preference Alignment (PA) objectives act as divergence estimators between aligned (chosen) and unaligned (rejected) response distributions. In this work, we extend this divergence-based perspective to general alignment settings, such as reinforcement learning with verifiable rewards (RLVR), where only environmental rewards are available. Within this unified framework, we propose f-Group Relative Policy Optimization (f-GRPO), a class of on-policy reinforcement learning, and f-Hybrid Alignment Loss (f-HAL), a hybrid on/off policy objectives, for general LLM alignment based on variational representation of f-divergences. We provide theoretical guarantees that these classes of objectives improve the average reward after alignment. Empirically, we validate our framework on both RLVR (Math Reasoning) and PA tasks (Safety Alignment), demonstrating superior performance and flexibility compared to current methods.
[1137] Mechanisms of AI Protein Folding in ESMFold
Kevin Lu, Jannik Brinkmann, Stefan Huber, Aaron Mueller, Yonatan Belinkov, David Bau, Chris Wendler
Main category: cs.LG
TL;DR: ESMFold’s protein folding process involves two computational stages: early blocks initialize pairwise biochemical signals from sequence, while late blocks develop spatial features like distance and contact information.
Details
Motivation: To understand how protein structure prediction models like ESMFold actually fold proteins by investigating the computational mechanisms behind folding a beta hairpin structural motif.Method: Used counterfactual interventions on model latents to trace ESMFold’s folding process, analyzing how representations evolve through different blocks of the model architecture.
Result: Identified two distinct computational stages: (1) early blocks transfer residue identities and biochemical features from sequence to pairwise representations, (2) late blocks accumulate spatial information like distance and contact data in pairwise representations.
Conclusion: ESMFold’s structural decisions can be localized, traced through interpretable representations, and manipulated with strong causal effects, revealing the model’s internal folding mechanisms.
Abstract: How do protein structure prediction models fold proteins? We investigate this question by tracing how ESMFold folds a beta hairpin, a prevalent structural motif. Through counterfactual interventions on model latents, we identify two computational stages in the folding trunk. In the first stage, early blocks initialize pairwise biochemical signals: residue identities and associated biochemical features such as charge flow from sequence representations into pairwise representations. In the second stage, late blocks develop pairwise spatial features: distance and contact information accumulate in the pairwise representation. We demonstrate that the mechanisms underlying structural decisions of ESMFold can be localized, traced through interpretable representations, and manipulated with strong causal effects.
[1138] Temperature Scaling Attack Disrupting Model Confidence in Federated Learning
Kichang Lee, Jaeho Jin, JaeYeon Park, Songkuk Kim, JeongGil Ko
Main category: cs.LG
TL;DR: A federated learning attack called Temperature Scaling Attack (TSA) that degrades confidence calibration while preserving accuracy, evading detection and causing critical failures in mission-critical systems.
Details
Motivation: Predictive confidence is crucial for risk-aware decision making in mission-critical systems, but existing federated learning attacks focus on accuracy or backdoors rather than confidence calibration. The paper identifies calibration as a distinct and critical attack surface.Method: TSA injects temperature scaling with learning rate-temperature coupling during local training. Malicious updates maintain benign-like optimization behavior to evade accuracy-based monitoring and similarity-based detection while systematically distorting confidence calibration.
Result: TSA substantially shifts calibration (145% error increase on CIFAR-100) with <2% accuracy change, remains effective under robust aggregation and post-hoc calibration defenses, and causes up to 7.2x increases in missed critical cases or false alarms in healthcare and autonomous driving applications.
Conclusion: Calibration integrity is a critical attack surface in federated learning that requires specific defenses beyond accuracy monitoring, as confidence manipulation can cause severe failures even when accuracy appears unchanged.
Abstract: Predictive confidence serves as a foundational control signal in mission-critical systems, directly governing risk-aware logic such as escalation, abstention, and conservative fallback. While prior federated learning attacks predominantly target accuracy or implant backdoors, we identify confidence calibration as a distinct attack objective. We present the Temperature Scaling Attack (TSA), a training-time attack that degrades calibration while preserving accuracy. By injecting temperature scaling with learning rate-temperature coupling during local training, malicious updates maintain benign-like optimization behavior, evading accuracy-based monitoring and similarity-based detection. We provide a convergence analysis under non-IID settings, showing that this coupling preserves standard convergence bounds while systematically distorting confidence. Across three benchmarks, TSA substantially shifts calibration (e.g., 145% error increase on CIFAR-100) with <2 accuracy change, and remains effective under robust aggregation and post-hoc calibration defenses. Case studies further show that confidence manipulation can cause up to 7.2x increases in missed critical cases (healthcare) or false alarms (autonomous driving), even when accuracy is unchanged. Overall, our results establish calibration integrity as a critical attack surface in federated learning.
[1139] A Fast and Generalizable Fourier Neural Operator-Based Surrogate for Melt-Pool Prediction in Laser Processing
Alix Benoit, Toni Ivas, Mateusz Papierz, Asel Sagingalieva, Alexey Melnikov, Elia Iseli
Main category: cs.LG
TL;DR: LP-FNO uses Fourier Neural Operators as a surrogate model for laser welding simulations, achieving 100,000x speedup with high accuracy in predicting 3D temperature fields and melt-pool boundaries.
Details
Motivation: High-fidelity laser welding simulations are computationally expensive, limiting large-scale process exploration and real-time applications. There's a need for efficient surrogate models that can accelerate these simulations while maintaining accuracy.Method: Developed Laser Processing Fourier Neural Operator (LP-FNO) based on Fourier Neural Operators. Reformulated transient problem in moving laser frame with temporal averaging to create quasi-steady state setting. Maps process parameters to 3D temperature fields and melt-pool boundaries using normalized enthalpy formulation across conduction and keyhole regimes.
Result: Achieves temperature prediction errors around 1% and intersection-over-union scores over 0.9 for melt-pool segmentation. Can be trained on coarse-resolution data and evaluated on finer grids for super-resolved predictions. Provides 100,000x speedup compared to traditional Finite Volume software.
Conclusion: LP-FNO offers an efficient surrogate modeling framework for laser welding that enables rapid prediction of full 3D fields and phase interfaces over wide parameter ranges in milliseconds, bridging the gap between accuracy and computational efficiency.
Abstract: High-fidelity simulations of laser welding capture complex thermo-fluid phenomena, including phase change, free-surface deformation, and keyhole dynamics, however their computational cost limits large-scale process exploration and real-time use. In this work we present the Laser Processing Fourier Neural Operator (LP-FNO), a Fourier Neural Operator (FNO) based surrogate model that learns the parametric solution operator of various laser processes from multiphysics simulations generated with FLOW-3D WELD (registered trademark). Through a novel approach of reformulating the transient problem in the moving laser frame and applying temporal averaging, the system results in a quasi-steady state setting suitable for operator learning, even in the keyhole welding regime. The proposed LP-FNO maps process parameters to three-dimensional temperature fields and melt-pool boundaries across a broad process window spanning conduction and keyhole regimes using the non-dimensional normalized enthalpy formulation. The model achieves temperature prediction errors on the order of 1% and intersection-over-union scores for melt-pool segmentation over 0.9. We demonstrate that a LP-FNO model trained on coarse-resolution data can be evaluated on finer grids, yielding accurate super-resolved predictions in mesh-converged conduction regimes, whereas discrepancies in keyhole regimes reflect unresolved dynamics in the coarse-mesh training data. These results indicate that the LP-FNO provides an efficient surrogate modeling framework for laser welding, enabling prediction of full three-dimensional fields and phase interfaces over wide parameter ranges in just tens of milliseconds, up to a hundred thousand times faster than traditional Finite Volume multi-physics software.
[1140] Zero-shot Generalizable Graph Anomaly Detection with Mixture of Riemannian Experts
Xinyu Zhao, Qingyun Sun, Jiayi Luo, Xingcheng Fu, Jianxin Li
Main category: cs.LG
TL;DR: GAD-MoRE: A zero-shot graph anomaly detection framework using mixture of Riemannian experts to handle diverse geometric anomaly patterns across domains.
Details
Motivation: Existing zero-shot graph anomaly detection methods ignore intrinsic geometric differences across anomaly patterns, limiting cross-domain generalization. Anomaly detectability depends on underlying geometric properties, and using a single static curvature space distorts structural signatures of anomalies.Method: Proposes GAD-MoRE with: 1) Multiple specialized Riemannian expert networks each in distinct curvature spaces, 2) Anomaly-aware multi-curvature feature alignment module to project inputs into parallel Riemannian spaces, 3) Memory-based dynamic router that adaptively assigns inputs to most compatible expert based on historical reconstruction performance.
Result: Extensive experiments in zero-shot setting show GAD-MoRE significantly outperforms state-of-the-art generalist GAD baselines, and even surpasses strong competitors that are few-shot fine-tuned with labeled data from target domain.
Conclusion: The mixture of Riemannian experts architecture effectively addresses geometry-dependent anomaly patterns, enabling better zero-shot generalization across diverse graph domains by capturing intrinsic geometric characteristics of anomalies.
Abstract: Graph Anomaly Detection (GAD) aims to identify irregular patterns in graph data, and recent works have explored zero-shot generalist GAD to enable generalization to unseen graph datasets. However, existing zero-shot GAD methods largely ignore intrinsic geometric differences across diverse anomaly patterns, substantially limiting their cross-domain generalization. In this work, we reveal that anomaly detectability is highly dependent on the underlying geometric properties and that embedding graphs from different domains into a single static curvature space can distort the structural signatures of anomalies. To address the challenge that a single curvature space cannot capture geometry-dependent graph anomaly patterns, we propose GAD-MoRE, a novel framework for zero-shot Generalizable Graph Anomaly Detection with a Mixture of Riemannian Experts architecture. Specifically, to ensure that each anomaly pattern is modeled in the Riemannian space where it is most detectable, GAD-MoRE employs a set of specialized Riemannian expert networks, each operating in a distinct curvature space. To align raw node features with curvature-specific anomaly characteristics, we introduce an anomaly-aware multi-curvature feature alignment module that projects inputs into parallel Riemannian spaces, enabling the capture of diverse geometric characteristics. Finally, to facilitate better generalization beyond seen patterns, we design a memory-based dynamic router that adaptively assigns each input to the most compatible expert based on historical reconstruction performance on similar anomalies. Extensive experiments in the zero-shot setting demonstrate that GAD-MoRE significantly outperforms state-of-the-art generalist GAD baselines, and even surpasses strong competitors that are few-shot fine-tuned with labeled data from the target domain.
[1141] Refining the Information Bottleneck via Adversarial Information Separation
Shuai Ning, Zhenpeng Wang, Lin Wang, Bing Chen, Shuangrong Liu, Xu Wu, Jin Zhou, Bo Yang
Main category: cs.LG
TL;DR: AdverISF: A self-supervised adversarial framework that separates task-relevant features from noise without explicit supervision, using statistical independence enforcement and multi-layer noise recycling for better generalization in data-scarce domains like material science.
Details
Motivation: In domains like material science, experimental datasets have task-relevant features heavily confounded by measurement noise and experimental artifacts. Standard regularization fails to precisely separate meaningful features from noise, while existing adversarial adaptation methods require explicit separation labels which are often unavailable.Method: Proposes Adversarial Information Separation Framework (AdverISF) with: 1) self-supervised adversarial mechanism to enforce statistical independence between task-relevant features and noise representations, 2) multi-layer separation architecture that progressively recycles noise information across feature hierarchies to recover features inadvertently discarded as noise.
Result: Extensive experiments show AdverISF outperforms state-of-the-art methods in data-scarce scenarios. Evaluations on real-world material design tasks demonstrate superior generalization performance compared to existing approaches.
Conclusion: AdverISF effectively isolates task-relevant features from noise without requiring explicit supervision, enabling finer-grained feature extraction and better generalization in data-scarce domains with noisy experimental data.
Abstract: Generalizing from limited data is particularly critical for models in domains such as material science, where task-relevant features in experimental datasets are often heavily confounded by measurement noise and experimental artifacts. Standard regularization techniques fail to precisely separate meaningful features from noise, while existing adversarial adaptation methods are limited by their reliance on explicit separation labels. To address this challenge, we propose the Adversarial Information Separation Framework (AdverISF), which isolates task-relevant features from noise without requiring explicit supervision. AdverISF introduces a self-supervised adversarial mechanism to enforce statistical independence between task-relevant features and noise representations. It further employs a multi-layer separation architecture that progressively recycles noise information across feature hierarchies to recover features inadvertently discarded as noise, thereby enabling finer-grained feature extraction. Extensive experiments demonstrate that AdverISF outperforms state-of-the-art methods in data-scarce scenarios. In addition, evaluations on real-world material design tasks show that it achieves superior generalization performance.
[1142] Improved Sampling Schedules for Discrete Diffusion Models
Alberto Foresti, Mustapha Bounoua, Giulio Franzese, Luca Ambrogioni, Pietro Michiardi
Main category: cs.LG
TL;DR: Discrete diffusion models for sequence data analyzed through thermodynamic entropy production, leading to novel sampling schedules (EDS and WDS) that outperform state-of-the-art methods across multiple domains.
Details
Motivation: Discrete diffusion models lack the theoretical understanding that continuous diffusion models have, particularly regarding the information-theoretic principles governing their reverse processes. The authors aim to bridge this gap by analyzing reverse process dynamics through thermodynamic entropy production.Method: The paper analyzes discrete diffusion reverse processes using thermodynamic entropy production theory, proposing entropy production rate as a proxy for information generation. This leads to a bound on Wasserstein distance between intermediate states and data distribution. Based on these insights, the authors introduce two novel sampling schedules: Entropic Discrete Schedule (EDS) with constant information gain rate, and Wasserstein Discrete Schedule (WDS) with equal Wasserstein distance steps.
Result: The proposed schedules significantly outperform state-of-the-art strategies across diverse domains including synthetic data, music notation, vision, and language modeling. They achieve superior performance at lower computational budgets.
Conclusion: Thermodynamic entropy production provides a rigorous framework for understanding discrete diffusion models, enabling the development of optimized sampling schedules that improve efficiency and performance across multiple application domains.
Abstract: Discrete diffusion models have emerged as a powerful paradigm for generative modeling on sequence data; however, the information-theoretic principles governing their reverse processes remain significantly less understood than those of their continuous counterparts. In this work, we bridge this gap by analyzing the reverse process dynamics through the lens of thermodynamic entropy production. We propose the entropy production rate as a rigorous proxy for quantifying information generation, deriving as a byproduct a bound on the Wasserstein distance between intermediate states and the data distribution. Leveraging these insights, we introduce two novel sampling schedules that are uniformly spaced with respect to their corresponding physics-inspired metrics: the Entropic Discrete Schedule (EDS), which is defined by maintaining a constant rate of information gain, and the Wasserstein Discrete Schedule (WDS), which is defined by taking equal steps in terms of the Wasserstein distance. We empirically demonstrate that our proposed schedules significantly outperform state-of-the-art strategies across diverse application domains, including synthetic data, music notation, vision and language modeling, consistently achieving superior performance at a lower computational budget.
[1143] Robustness Beyond Known Groups with Low-rank Adaptation
Abinitha Gourabathina, Hyewon Jeong, Teya Bergamaschi, Marzyeh Ghassemi, Collin Stultz
Main category: cs.LG
TL;DR: LEIA improves group robustness by identifying low-dimensional error subspaces and applying low-rank adjustments to classifier logits without needing group labels or modifying backbone models.
Details
Motivation: Deep learning models often fail systematically on specific subpopulations, but existing group-robust methods require prior knowledge of relevant subgroups through group annotations. There's a need for methods that improve performance on sensitive subgroups without requiring pre-specified group labels.Method: Two-stage method: 1) Identifies a low-dimensional subspace in representation space where model errors concentrate, 2) Restricts adaptation to this error-informed subspace via low-rank adjustment to classifier logits. Works without modifying backbone or requiring group labels.
Result: Tested on five real-world datasets across three settings (no knowledge, partial knowledge, full knowledge of subgroup relevance). LEIA consistently improves worst-group performance while being fast, parameter-efficient, and robust to hyperparameter choice.
Conclusion: LEIA provides an effective approach for improving group robustness without requiring group annotations, addressing systematic failures on unknown subpopulations through targeted low-dimensional adaptation.
Abstract: Deep learning models trained to optimize average accuracy often exhibit systematic failures on particular subpopulations. In real world settings, the subpopulations most affected by such disparities are frequently unlabeled or unknown, thereby motivating the development of methods that are performant on sensitive subgroups without being pre-specified. However, existing group-robust methods typically assume prior knowledge of relevant subgroups, using group annotations for training or model selection. We propose Low-rank Error Informed Adaptation (LEIA), a simple two-stage method that improves group robustness by identifying a low-dimensional subspace in the representation space where model errors concentrate. LEIA restricts adaptation to this error-informed subspace via a low-rank adjustment to the classifier logits, directly targeting latent failure modes without modifying the backbone or requiring group labels. Using five real-world datasets, we analyze group robustness under three settings: (1) truly no knowledge of subgroup relevance, (2) partial knowledge of subgroup relevance, and (3) full knowledge of subgroup relevance. Across all settings, LEIA consistently improves worst-group performance while remaining fast, parameter-efficient, and robust to hyperparameter choice.
cs.MA
[1144] Lemon Agent Technical Report
Haipeng Jiang, Kailong Ren, Zimo Yin, Zhetao Sun, Xin Gan, Guangyi Lv, Ming He, Peng Wang, Congli Yin, Hong Pan, Changwen Zhang, Shan Tong, Zhengyu Xu, Zeping Chen, Yubin Huangfu, Yanzhi Xu, Xing Su, Qin Feng, Dong An, Jianping Fan
Main category: cs.MA
TL;DR: Lemon Agent: A multi-agent orchestrator-worker system with hierarchical self-adaptive scheduling, progressive context management, and self-evolving memory for efficient complex task execution.
Details
Motivation: Current LLM-powered agent systems suffer from limitations in resource efficiency, context management, and multimodal perception when handling complex, long-horizon tasks.Method: Proposes AgentCortex framework with two-tier architecture: orchestrator-worker system with hierarchical self-adaptive scheduling, three-tier progressive context management, self-evolving memory system, and enhanced MCP toolset.
Result: Achieves state-of-the-art 91.36% overall accuracy on GAIA benchmark and top position on xbench-DeepSearch leaderboard with score of 77+.
Conclusion: Lemon Agent demonstrates superior performance in complex task execution through its adaptive multi-agent architecture, achieving optimal balance between global coordination and local execution.
Abstract: Recent advanced LLM-powered agent systems have exhibited their remarkable capabilities in tackling complex, long-horizon tasks. Nevertheless, they still suffer from inherent limitations in resource efficiency, context management, and multimodal perception. Based on these observations, Lemon Agent is introduced, a multi-agent orchestrator-worker system built on a newly proposed AgentCortex framework, which formalizes the classic Planner-Executor-Memory paradigm through an adaptive task execution mechanism. Our system integrates a hierarchical self-adaptive scheduling mechanism that operates at both the overall orchestrator layer and workers layer. This mechanism can dynamically adjust computational intensity based on task complexity. It enables orchestrator to allocate one or more workers for parallel subtask execution, while workers can further improve operational efficiency by invoking tools concurrently. By virtue of this two-tier architecture, the system achieves synergistic balance between global task coordination and local task execution, thereby optimizing resource utilization and task processing efficiency in complex scenarios. To reduce context redundancy and increase information density during parallel steps, we adopt a three-tier progressive context management strategy. To make fuller use of historical information, we propose a self-evolving memory system, which can extract multi-dimensional valid information from all historical experiences to assist in completing similar tasks. Furthermore, we provide an enhanced MCP toolset. Empirical evaluations on authoritative benchmarks demonstrate that our Lemon Agent can achieve a state-of-the-art 91.36% overall accuracy on GAIA and secures the top position on the xbench-DeepSearch leaderboard with a score of 77+.
[1145] The Value of Variance: Mitigating Debate Collapse in Multi-Agent Systems via Uncertainty-Driven Policy Optimization
Luoxi Tang, Yuqiao Meng, Joseph Costa, Yingxue Zhang, Muchao Ye, Zhaohan Xi
Main category: cs.MA
TL;DR: Proposes hierarchical uncertainty metrics for multi-agent debate systems to detect debate collapse failures, and develops uncertainty-driven policy optimization to mitigate such failures.
Details
Motivation: Multi-agent debate systems improve LLM reasoning but are vulnerable to debate collapse where final decisions are compromised by erroneous reasoning. Existing methods lack principled mechanisms to detect or prevent such failures.Method: 1) Proposes hierarchical uncertainty metrics at three levels: intra-agent (individual reasoning uncertainty), inter-agent (interactive uncertainty), and system-level (output uncertainty). 2) Develops uncertainty-driven policy optimization that penalizes self-contradiction, peer conflict, and low-confidence outputs in dynamic debating environments.
Result: Empirical analysis shows proposed uncertainty quantification reliably indicates system failures. Experiments demonstrate uncertainty-driven mitigation reliably calibrates multi-agent systems by consistently improving decision accuracy while reducing system disagreement.
Conclusion: The hierarchical uncertainty framework provides effective diagnostic metrics for multi-agent debate failures, and the uncertainty-driven policy optimization successfully mitigates debate collapse while improving system reliability.
Abstract: Multi-agent debate (MAD) systems improve LLM reasoning through iterative deliberation, but remain vulnerable to debate collapse, a failure type where final agent decisions are compromised on erroneous reasoning. Existing methods lack principled mechanisms to detect or prevent such failures. To address this gap, we first propose a hierarchical metric that quantifies behavioral uncertainty at three levels: intra-agent (individual reasoning uncertainty), inter-agent (interactive uncertainty), and system-level (output uncertainty). Empirical analysis across several benchmarks reveals that our proposed uncertainty quantification reliably indicates system failures, which demonstrates the validity of using them as diagnostic metrics to indicate the system failure. Subsequently, we propose a mitigation strategy by formulating an uncertainty-driven policy optimization to penalize self-contradiction, peer conflict, and low-confidence outputs in a dynamic debating environment. Experiments demonstrate that our proposed uncertainty-driven mitigation reliably calibrates the multi-agent system by consistently improving decision accuracy while reducing system disagreement.
[1146] Talk, Judge, Cooperate: Gossip-Driven Indirect Reciprocity in Self-Interested LLM Agents
Shuhui Zhu, Yue Lin, Shriya Kaistha, Wenhao Li, Baoxiang Wang, Hongyuan Zha, Gillian K. Hadfield, Pascal Poupart
Main category: cs.MA
TL;DR: ALIGN framework uses LLM agents with strategic gossip sharing to sustain indirect reciprocity in decentralized systems without changing intrinsic incentives.
Details
Motivation: Indirect reciprocity (helping those who help others) is difficult to maintain among self-interested LLM agents without reliable reputation systems, requiring new approaches for decentralized cooperation.Method: Agentic Linguistic Gossip Network (ALIGN) framework where agents strategically share open-ended gossip using hierarchical tones to evaluate trustworthiness and coordinate social norms in a decentralized manner.
Result: ALIGN consistently improves indirect reciprocity and resists malicious entrants by identifying and ostracizing defectors. Stronger LLM reasoning capabilities lead to more incentive-aligned cooperation, while chat models often over-cooperate suboptimally.
Conclusion: Leveraging LLM reasoning through decentralized gossip is promising for maintaining social welfare in agentic ecosystems, with reasoning capabilities being crucial for strategic alignment.
Abstract: Indirect reciprocity, which means helping those who help others, is difficult to sustain among decentralized, self-interested LLM agents without reliable reputation systems. We introduce Agentic Linguistic Gossip Network (ALIGN), an automated framework where agents strategically share open-ended gossip using hierarchical tones to evaluate trustworthiness and coordinate social norms. We demonstrate that ALIGN consistently improves indirect reciprocity and resists malicious entrants by identifying and ostracizing defectors without changing intrinsic incentives. Notably, we find that stronger reasoning capabilities in LLMs lead to more incentive-aligned cooperation, whereas chat models often over-cooperate even when strategically suboptimal. These results suggest that leveraging LLM reasoning through decentralized gossip is a promising path for maintaining social welfare in agentic ecosystems. Our code is available at https://github.com/shuhui-zhu/ALIGN.
[1147] Altruism and Fair Objective in Mixed-Motive Markov games
Yao-hua Franck Xu, Tayeb Lemlouma, Arnaud Braud, Jean-Marie Bonnin
Main category: cs.MA
TL;DR: Proposes a fairness-focused multi-agent cooperation framework using Proportional Fairness instead of utilitarian welfare, with fair altruistic utilities and novel fair Actor-Critic algorithms for sequential social dilemmas.
Details
Motivation: Standard utilitarian approaches to multi-agent cooperation can produce efficient but highly inequitable outcomes. There's a need for frameworks that foster fairer cooperation in social dilemmas where individual interests conflict with collective outcomes.Method: Replaces utilitarian objective with Proportional Fairness, defines fair altruistic utility in individual log-payoff space, establishes analytical conditions for cooperation, extends to sequential settings via Fair Markov Games, and develops novel fair Actor-Critic algorithms.
Result: The framework enables fairer cooperation in social dilemmas, with analytical guarantees and practical algorithms that can be evaluated in various social dilemma environments.
Conclusion: Proportional Fairness provides a viable alternative to utilitarian welfare for achieving fair cooperation in multi-agent systems, with theoretical foundations and practical algorithms for both one-shot and sequential settings.
Abstract: Cooperation is fundamental for society’s viability, as it enables the emergence of structure within heterogeneous groups that seek collective well-being. However, individuals are inclined to defect in order to benefit from the group’s cooperation without contributing the associated costs, thus leading to unfair situations. In game theory, social dilemmas entail this dichotomy between individual interest and collective outcome. The most dominant approach to multi-agent cooperation is the utilitarian welfare which can produce efficient highly inequitable outcomes. This paper proposes a novel framework to foster fairer cooperation by replacing the standard utilitarian objective with Proportional Fairness. We introduce a fair altruistic utility for each agent, defined on the individual log-payoff space and derive the analytical conditions required to ensure cooperation in classic social dilemmas. We then extend this framework to sequential settings by defining a Fair Markov Game and deriving novel fair Actor-Critic algorithms to learn fair policies. Finally, we evaluate our method in various social dilemma environments.
[1148] EvoCorps: An Evolutionary Multi-Agent Framework for Depolarizing Online Discourse
Ning Lin, Haolun Li, Mingshu Liu, Chengyun Ruan, Kaibo Huang, Yukun Wei, Zhongliang Yang, Linna Zhou
Main category: cs.MA
TL;DR: EvoCorps is an evolutionary multi-agent framework for proactive depolarization in online discourse, using coordinated AI agents for monitoring, planning, generation, and diffusion to counter adversarial amplification in real-time.
Details
Motivation: Current approaches to online discourse governance are largely diagnostic and post-hoc, suffering from latency and static policies that cannot effectively counter coordinated adversarial amplification that evolves in real-time.Method: EvoCorps frames discourse governance as a dynamic social game with coordinated multi-agent roles (monitoring, planning, grounded generation, multi-identity diffusion). It uses retrieval-augmented collective cognition for factual grounding and action-outcome memory, with closed-loop evolutionary learning to adapt strategies as the environment and attackers change.
Result: Implemented on MOSAIC social-AI simulation platform with controlled evaluation in multi-source news stream with adversarial injection and amplification. EvoCorps improves discourse outcomes across emotional polarization, viewpoint extremity, and argumentative rationality compared to adversarial baseline.
Conclusion: EvoCorps provides a practical path from detection and post-hoc mitigation to in-process, closed-loop intervention for online discourse depolarization, demonstrating effectiveness against adversarial amplification.
Abstract: Polarization in online discourse erodes social trust and accelerates misinformation, yet technical responses remain largely diagnostic and post-hoc. Current governance approaches suffer from inherent latency and static policies, struggling to counter coordinated adversarial amplification that evolves in real-time. We present EvoCorps, an evolutionary multi-agent framework for proactive depolarization. EvoCorps frames discourse governance as a dynamic social game and coordinates roles for monitoring, planning, grounded generation, and multi-identity diffusion. A retrieval-augmented collective cognition core provides factual grounding and action–outcome memory, while closed-loop evolutionary learning adapts strategies as the environment and attackers change. We implement EvoCorps on the MOSAIC social-AI simulation platform for controlled evaluation in a multi-source news stream with adversarial injection and amplification. Across emotional polarization, viewpoint extremity, and argumentative rationality, EvoCorps improves discourse outcomes over an adversarial baseline, pointing to a practical path from detection and post-hoc mitigation to in-process, closed-loop intervention. The code is available at https://github.com/ln2146/EvoCorps.
[1149] ValueFlow: Measuring the Propagation of Value Perturbations in Multi-Agent LLM Systems
Jinnuo Liu, Chuke Liu, Hua Shen
Main category: cs.MA
TL;DR: ValueFlow: A framework for measuring value drift in multi-agent LLM systems using perturbation-based evaluation and structural analysis
Details
Motivation: Multi-agent LLM systems involve agents observing and responding to each other's outputs, but current value alignment evaluations focus on isolated models, leaving value perturbation propagation through agent interactions poorly understood.Method: ValueFlow introduces a 56-value evaluation dataset from Schwartz Value Survey and uses LLM-as-a-judge protocol to quantify agents’ value orientations during interactions. It decomposes value drift into agent-level response behavior (beta-susceptibility) and system-level structural effects (system susceptibility), analyzing how perturbations propagate through network structures.
Result: Experiments across multiple model backbones, prompt personas, value dimensions, and network structures show that susceptibility varies widely across values and is strongly shaped by structural topology.
Conclusion: ValueFlow provides a systematic framework for understanding value drift in multi-agent systems, revealing how structural topology influences susceptibility to value perturbations across different value dimensions.
Abstract: Multi-agent large language model (LLM) systems increasingly consist of agents that observe and respond to one another’s outputs. While value alignment is typically evaluated for isolated models, how value perturbations propagate through agent interactions remains poorly understood. We present ValueFlow, a perturbation-based evaluation framework for measuring and analyzing value drift in multi-agent systems. ValueFlow introduces a 56-value evaluation dataset derived from the Schwartz Value Survey and quantifies agents’ value orientations during interaction using an LLM-as-a-judge protocol. Building on this measurement layer, ValueFlow decomposes value drift into agent-level response behavior and system-level structural effects, operationalized by two metrics: beta-susceptibility, which measures an agent’s sensitivity to perturbed peer signals, and system susceptibility (SS), which captures how node-level perturbations affect final system outputs. Experiments across multiple model backbones, prompt personas, value dimensions, and network structures show that susceptibility varies widely across values and is strongly shaped by structural topology.
[1150] Teaching an Old Dynamics New Tricks: Regularization-free Last-iterate Convergence in Zero-sum Games via BNN Dynamics
Tuo Zhang, Leonardo Stella
Main category: cs.MA
TL;DR: BNN dynamics from evolutionary game theory applied to zero-sum games without regularization, with theoretical guarantees and neural implementation for both normal-form and extensive-form games.
Details
Motivation: Existing methods for adversarial training in multi-agent learning require regularization with hyperparameter tuning, which is challenging especially when payoff structure is unknown or changing. The paper aims to develop a regularization-free approach.Method: Repurpose Brown-von Neumann-Nash (BNN) dynamics from evolutionary game theory, which intrinsically converges in zero-sum games without regularization. Develop framework integrating BNN dynamics in extensive-form games through counterfactual weighting, and implement with neural function approximation.
Result: Provides last-iterate convergence guarantees in noisy normal-form games. Empirical results show the method quickly adapts to nonstationarities and outperforms state-of-the-art regularization-based approaches.
Conclusion: BNN dynamics offer a promising regularization-free alternative for adversarial training in multi-agent learning, with theoretical guarantees and practical scalability through neural implementation.
Abstract: Zero-sum games are a fundamental setting for adversarial training and decision-making in multi-agent learning (MAL). Existing methods often ensure convergence to (approximate) Nash equilibria by introducing a form of regularization. Yet, regularization requires additional hyperparameters, which must be carefully tuned–a challenging task when the payoff structure is known, and considerably harder when the structure is unknown or subject to change. Motivated by this problem, we repurpose a classical model in evolutionary game theory, i.e., the Brown-von Neumann-Nash (BNN) dynamics, by leveraging the intrinsic convergence of this dynamics in zero-sum games without regularization, and provide last-iterate convergence guarantees in noisy normal-form games (NFGs). Importantly, to make this approach more applicable, we develop a novel framework with theoretical guarantees that integrates the BNN dynamics in extensive-form games (EFGs) through counterfactual weighting. Furthermore, we implement an algorithm that instantiates our framework with neural function approximation, enabling scalable learning in both NFGs and EFGs. Empirical results show that our method quickly adapts to nonstationarities, outperforming the state-of-the-art regularization-based approach.
[1151] Learning to Coordinate via Quantum Entanglement in Multi-Agent Reinforcement Learning
John Gardiner, Orlando Romero, Brendan Tivnan, Nicolò Dal Fabbro, George J. Pappas
Main category: cs.MA
TL;DR: A framework for training multi-agent reinforcement learning agents to use quantum entanglement as a coordination resource, enabling communication-free correlated policies that outperform classical shared randomness approaches.
Details
Motivation: Prior MARL work uses shared randomness for coordination, but quantum entanglement offers a larger class of communication-free correlated policies. Quantum physics shows that for certain cooperative games without communication, shared entanglement enables strategies that outperform classical shared randomness approaches (quantum advantage).Method: Novel differentiable policy parameterization that enables optimization over quantum measurements, combined with a policy architecture that decomposes joint policies into a quantum coordinator and decentralized local actors.
Result: The method learns strategies that attain quantum advantage in single-round games treated as black box oracles, and demonstrates quantum advantage in multi-agent sequential decision-making problems formulated as Dec-POMDPs.
Conclusion: The framework successfully enables MARL agents to exploit quantum entanglement as a coordination resource, achieving quantum advantage in both single-round games and sequential decision-making problems.
Abstract: The inability to communicate poses a major challenge to coordination in multi-agent reinforcement learning (MARL). Prior work has explored correlating local policies via shared randomness, sometimes in the form of a correlation device, as a mechanism to assist in decentralized decision-making. In contrast, this work introduces the first framework for training MARL agents to exploit shared quantum entanglement as a coordination resource, which permits a larger class of communication-free correlated policies than shared randomness alone. This is motivated by well-known results in quantum physics which posit that, for certain single-round cooperative games with no communication, shared quantum entanglement enables strategies that outperform those that only use shared randomness. In such cases, we say that there is quantum advantage. Our framework is based on a novel differentiable policy parameterization that enables optimization over quantum measurements, together with a novel policy architecture that decomposes joint policies into a quantum coordinator and decentralized local actors. To illustrate the effectiveness of our proposed method, we first show that we can learn, purely from experience, strategies that attain quantum advantage in single-round games that are treated as black box oracles. We then demonstrate how our machinery can learn policies with quantum advantage in an illustrative multi-agent sequential decision-making problem formulated as a decentralized partially observable Markov decision process (Dec-POMDP).
[1152] MAFE: Enabling Equitable Algorithm Design in Multi-Agent Multi-Stage Decision-Making Systems
Zachary McBride Lazri, Anirudh Nakra, Ivan Brugere, Danial Dervovic, Antigoni Polychroniadou, Furong Huang, Dana Dachman-Soled, Min Wu
Main category: cs.MA
TL;DR: MAFE is a suite of Multi-Agent Fair Environments for simulating realistic, modular systems where fairness emerges from multiple interacting agents’ decisions over time, addressing limitations of single-agent fairness approaches.
Details
Motivation: Real-world decision-making systems often involve multiple interacting entities whose multi-stage actions jointly influence long-term outcomes, but existing fairness methods applied at isolated decision points fail to mitigate disparities that accumulate over time. Current sequential fairness approaches assume centralized agents or simplified dynamics, limiting applicability to complex social systems.Method: Introduces MAFE, a suite of Multi-Agent Fair Environments that simulate realistic, modular, and dynamic systems supporting heterogeneous agents, configurable interventions, and fairness metrics. The environments are open-source and compatible with standard multi-agent reinforcement learning (MARL) libraries, enabling reproducible evaluation of fairness-aware policies.
Result: Demonstrated MAFE across three domains (loan processing, healthcare, and higher education) with extensive experiments on cooperative use cases. The framework facilitates design of equitable multi-agent algorithms and reveals critical trade-offs between fairness, performance, and coordination.
Conclusion: MAFE provides a foundation for systematic progress in dynamic, multi-agent fairness research by enabling realistic simulation of fairness in complex, multi-stage decision-making systems with multiple interacting agents.
Abstract: Algorithmic fairness is often studied in static or single-agent settings, yet many real-world decision-making systems involve multiple interacting entities whose multi-stage actions jointly influence long-term outcomes. Existing fairness methods applied at isolated decision points frequently fail to mitigate disparities that accumulate over time. Although recent work has modeled fairness as a sequential decision-making problem, it typically assumes centralized agents or simplified dynamics, limiting its applicability to complex social systems. We introduce MAFE, a suite of Multi-Agent Fair Environments designed to simulate realistic, modular, and dynamic systems in which fairness emerges from the interplay of multiple agents. We demonstrate MAFEs across three domains – loan processing, healthcare, and higher education – that support heterogeneous agents, configurable interventions, and fairness metrics. The environments are open-source and compatible with standard multi-agent reinforcement learning (MARL) libraries, enabling reproducible evaluation of fairness-aware policies. Through extensive experiments on cooperative use cases, we demonstrate how MAFE facilitates the design of equitable multi-agent algorithms and reveals critical trade-offs between fairness, performance, and coordination. MAFE provides a foundation for systematic progress in dynamic, multi-agent fairness research.
[1153] Achieving Unanimous Consensus Through Multi-Agent Deliberation
Apurba Pokharel, Ram Dantu, Shakila Zaman, Vinh Quach, Sirisha Talapuru
Main category: cs.MA
TL;DR: A novel blockchain consensus mechanism using LLMs as rational agents in structured discussions to achieve unanimous or graded consensus through multi-round deliberation.
Details
Motivation: Traditional blockchain consensus mechanisms (PoW, PoS) are inadequate for decision-making scenarios where diverse opinions matter, as they focus on honest majority or weighted consensus rather than deliberation and unanimous agreement.Method: Uses Large Language Models as rational agents engaging in structured multi-round discussions. Implements graded consensus for prioritized decisions and unanimous consensus for definitive problems. Formalizes the system to maintain blockchain properties while addressing adversarial behavior, stalled deliberations, and consensus confidence.
Result: Experimental results demonstrate system feasibility, showing convergence, proper block properties, and accuracy. The approach enables deliberative decision-making on blockchain networks while maintaining blockchain security properties.
Conclusion: The proposed deliberation-based consensus mechanism using LLMs successfully addresses limitations of traditional blockchain consensus for decision-making scenarios, enabling structured discussion and agreement while maintaining blockchain integrity.
Abstract: Blockchain consensus mechanisms have relied on algorithms such as Proof-of-Work (PoW) and Proof-of-Stake (PoS) to ensure network functionality and integrity. However, these approaches struggle with adaptability for decision-making where the opinions of each matter rather than reaching an agreement based on honest majority or weighted consensus. This paper introduces a novel deliberation-based consensus mechanism where Large Language Models (LLMs) act as rational agents engaging in structured discussions to reach a unanimous consensus. By leveraging graded consensus and a multi-round deliberation process, our approach ensures unanimous consensus for definitive problems and graded consensus for prioritized decision problems and policies. We provide a formalization of our system and use it to show that the properties of blockchains are maintained, while also addressing the behavior in terms of adversaries, stalled deliberations, and confidence in consensus. Moreover, experimental results demonstrate system feasibility, showcasing convergence, block properties, and accuracy, which enable deliberative decision-making on blockchain networks.
[1154] Trade in Minutes! Rationality-Driven Agentic System for Quantitative Financial Trading
Zifan Song, Kaitao Song, Guosheng Hu, Ding Qi, Junyao Gao, Xiaohua Wang, Dongsheng Li, Cairong Zhao
Main category: cs.MA
TL;DR: TiMi is a rationality-driven multi-agent system for quantitative trading that decouples strategy development from minute-level deployment using LLMs for semantic analysis, code programming, and mathematical reasoning.
Details
Motivation: Current financial trading agents simulate anthropomorphic roles that introduce emotional biases and rely on peripheral information, while requiring continuous inference during deployment. The paper aims to harmonize strategic depth with mechanical rationality for quantitative trading.Method: TiMi uses a multi-agent system with specialized LLM capabilities in a policy-optimization-deployment chain. It features a two-tier analytical paradigm (macro patterns to micro customization), layered programming design for trading bot implementation, and closed-loop optimization driven by mathematical reflection.
Result: Extensive evaluations across 200+ trading pairs in stock and cryptocurrency markets show TiMi’s efficacy in stable profitability, action efficiency, and risk control under volatile market dynamics.
Conclusion: TiMi successfully demonstrates the potential of rationality-driven multi-agent systems for autonomic finance by combining LLM capabilities with quantitative trading principles.
Abstract: Recent advancements in large language models (LLMs) and agentic systems have shown exceptional decision-making capabilities, revealing significant potential for autonomic finance. Current financial trading agents predominantly simulate anthropomorphic roles that inadvertently introduce emotional biases and rely on peripheral information, while being constrained by the necessity for continuous inference during deployment. In this paper, we pioneer the harmonization of strategic depth in agents with the mechanical rationality essential for quantitative trading. Consequently, we present TiMi (Trade in Minutes), a rationality-driven multi-agent system that architecturally decouples strategy development from minute-level deployment. TiMi leverages specialized LLM capabilities of semantic analysis, code programming, and mathematical reasoning within a comprehensive policy-optimization-deployment chain. Specifically, we propose a two-tier analytical paradigm from macro patterns to micro customization, layered programming design for trading bot implementation, and closed-loop optimization driven by mathematical reflection. Extensive evaluations across 200+ trading pairs in stock and cryptocurrency markets empirically validate the efficacy of TiMi in stable profitability, action efficiency, and risk control under volatile market dynamics.
[1155] Aligning Microscopic Vehicle and Macroscopic Traffic Statistics: Reconstructing Driving Behavior from Partial Data
Zhihao Zhang, Keith Redmill, Chengyang Peng, Bowen Weng
Main category: cs.MA
TL;DR: A framework for autonomous driving that reconstructs microscopic vehicle states from macroscopic observations to learn policies that are both microscopically consistent with observed behaviors and macroscopically aligned with target traffic statistics.
Details
Motivation: Current autonomous driving approaches (imitation learning and RL) require high-quality microscopic driving data that is difficult and costly to obtain. While vehicle sensors provide microscopic data without context, and roadside sensors provide macroscopic data without vehicle-level detail, there's a need to bridge this gap for more effective autonomous driving policies.Method: Proposes a framework that reconstructs unobserved microscopic states from macroscopic observations, uses microscopic data to anchor observed vehicle behaviors, and learns a shared policy that is both microscopically consistent with partially observed trajectories and macroscopically aligned with target traffic statistics when deployed at population scale.
Result: The framework produces constrained and regularized policies that promote realistic traffic flow patterns and safe coordination with human drivers at scale, addressing the data limitations of current approaches.
Conclusion: By combining microscopic and macroscopic observations, the proposed framework enables more effective autonomous driving policies that work well with human drivers while requiring less expensive data collection.
Abstract: A driving algorithm that aligns with good human driving practices, or at the very least collaborates effectively with human drivers, is crucial for developing safe and efficient autonomous vehicles. In practice, two main approaches are commonly adopted: (i) supervised or imitation learning, which requires comprehensive naturalistic driving data capturing all states that influence a vehicle’s decisions and corresponding actions, and (ii) reinforcement learning (RL), where the simulated driving environment either matches or is intentionally more challenging than real-world conditions. Both methods depend on high-quality observations of real-world driving behavior, which are often difficult and costly to obtain. State-of-the-art sensors on individual vehicles can gather microscopic data, but they lack context about the surrounding conditions. Conversely, roadside sensors can capture traffic flow and other macroscopic characteristics, but they cannot associate this information with individual vehicles on a microscopic level. Motivated by this complementarity, we propose a framework that reconstructs unobserved microscopic states from macroscopic observations, using microscopic data to anchor observed vehicle behaviors, and learns a shared policy whose behavior is microscopically consistent with the partially observed trajectories and actions and macroscopically aligned with target traffic statistics when deployed population-wide. Such constrained and regularized policies promote realistic flow patterns and safe coordination with human drivers at scale.
[1156] Multi-Agent Teams Hold Experts Back
Aneesh Pappu, Batu El, Hancheng Cao, Carmelo di Nolfo, Yanchao Sun, Meng Cao, James Zou
Main category: cs.MA
TL;DR: Self-organizing LLM teams consistently fail to match expert agent performance, losing up to 37.6% performance due to poor expertise utilization through integrative compromise rather than proper expertise weighting.
Details
Motivation: To understand how self-organizing multi-agent LLM systems perform when coordination is unconstrained, rather than enforced through fixed roles or workflows, and whether they can achieve synergy where team performance matches or exceeds the best individual member.Method: Drawing on organizational psychology, studied self-organizing LLM teams across human-inspired and frontier ML benchmarks, analyzing conversational patterns to understand coordination failures and expertise utilization.
Result: LLM teams consistently fail to match expert agent’s performance (up to 37.6% loss), with expert leveraging being the primary bottleneck rather than identification. Teams show tendency toward integrative compromise (averaging views) rather than properly weighting expertise, which increases with team size and correlates negatively with performance.
Conclusion: Self-organizing multi-agent LLM teams have significant gap in harnessing collective expertise, showing consensus-seeking behavior that improves robustness to adversarial agents but creates trade-off between alignment and effective expertise utilization.
Abstract: Multi-agent LLM systems are increasingly deployed as autonomous collaborators, where agents interact freely rather than execute fixed, pre-specified workflows. In such settings, effective coordination cannot be fully designed in advance and must instead emerge through interaction. However, most prior work enforces coordination through fixed roles, workflows, or aggregation rules, leaving open the question of how well self-organizing teams perform when coordination is unconstrained. Drawing on organizational psychology, we study whether self-organizing LLM teams achieve strong synergy, where team performance matches or exceeds the best individual member. Across human-inspired and frontier ML benchmarks, we find that – unlike human teams – LLM teams consistently fail to match their expert agent’s performance, even when explicitly told who the expert is, incurring performance losses of up to 37.6%. Decomposing this failure, we show that expert leveraging, rather than identification, is the primary bottleneck. Conversational analysis reveals a tendency toward integrative compromise – averaging expert and non-expert views rather than appropriately weighting expertise – which increases with team size and correlates negatively with performance. Interestingly, this consensus-seeking behavior improves robustness to adversarial agents, suggesting a trade-off between alignment and effective expertise utilization. Our findings reveal a significant gap in the ability of self-organizing multi-agent teams to harness the collective expertise of their members.
[1157] On the Uncertainty of Large Language Model-Based Multi-Agent Systems
Yuxuan Zhao, Sijia Chen, Ningxin Su
Main category: cs.MA
TL;DR: Analysis of multi-agent systems (MAS) using LLMs through uncertainty perspective, finding single agents often outperform MAS, with entropy dynamics determining outcomes early. Introduces Entropy Judger algorithm for solution selection.
Details
Motivation: The mechanisms behind why multi-agent systems built on publicly available LLMs succeed or fail remain poorly understood. The paper aims to investigate MAS effectiveness through the lens of uncertainty dynamics during problem-solving.Method: Analyzes entropy transitions across various MAS topologies and six benchmark tasks using 245 features spanning token-, trajectory-, and round-level entropy. Investigates intra- and inter-agent uncertainty dynamics during problem-solving.
Result: Found single agents outperform MAS in ~43.3% of cases. Uncertainty dynamics are largely determined in first interaction round. Key observations: Certainty Preference (reducing uncertainty critical), Base Uncertainty (lower entropy benefits MAS), Task Awareness (entropy dynamics vary by task).
Conclusion: Proposes Entropy Judger algorithm for selecting solutions from MAS pass@k results, achieving consistent accuracy improvements across all configurations and tasks. Provides insights into uncertainty dynamics in LLM-based multi-agent systems.
Abstract: Multi-agent systems (MAS) have emerged as a prominent paradigm for leveraging large language models (LLMs) to tackle complex tasks. However, the mechanisms governing the effectiveness of MAS built upon publicly available LLMs, specifically the underlying rationales for their success or failure, remain largely unexplored. In this paper, we revisit MAS through the perspective of uncertainty, considering both intra- and inter-agent dynamics by investigating entropy transitions during problem-solving across various topologies and six benchmark tasks. By analyzing 245 features spanning token-, trajectory-, and round-level entropy, we counterintuitively find that a single agent outperforms MAS in approximately 43.3% of cases, and that uncertainty dynamics are largely determined during the first round of interaction. Furthermore, we provide three key observations: 1) Certainty Preference: reducing uncertainty at any stage for any agent is critical for guaranteeing correct solutions; 2) Base Uncertainty: base models with lower entropy during problem-solving directly benefit MAS performance; and 3) Task Awareness: entropy dynamics of MAS play varying roles across different tasks. Building on these insights, we introduce a simple yet effective algorithm, the Entropy Judger, to select solutions from MAS’s pass@k results, leading to consistent accuracy improvements across all MAS configurations and tasks. Our source code is available at https://github.com/AgenticFinLab/multiagent-entropy.
[1158] PhysicsAgentABM: Physics-Guided Generative Agent-Based Modeling
Kavana Venkatesh, Yinhan He, Jundong Li, Jiaming Cui
Main category: cs.MA
TL;DR: PhysicsAgentABM combines symbolic agents with neural transition models for scalable, calibrated agent-based simulations, reducing LLM calls via clustering.
Details
Motivation: LLM-based multi-agent systems are expensive to scale and poorly calibrated for timestep-aligned simulation, while classical ABMs struggle with rich individual-level signals and non-stationary behaviors.Method: Uses state-specialized symbolic agents for mechanistic priors, multimodal neural transition model for temporal/interaction dynamics, uncertainty-aware epistemic fusion for cluster-level transitions, and ANCHOR clustering strategy with contrastive loss to reduce LLM calls.
Result: Reduces LLM calls by 6-8 times, shows consistent gains in event-time accuracy and calibration over mechanistic, neural, and LLM baselines across public health, finance, and social sciences.
Conclusion: Establishes a new paradigm for scalable and calibrated simulation with LLMs by re-architecting generative ABM around population-level inference with uncertainty-aware neuro-symbolic fusion.
Abstract: Large language model (LLM)-based multi-agent systems enable expressive agent reasoning but are expensive to scale and poorly calibrated for timestep-aligned state-transition simulation, while classical agent-based models (ABMs) offer interpretability but struggle to integrate rich individual-level signals and non-stationary behaviors. We propose PhysicsAgentABM, which shifts inference to behaviorally coherent agent clusters: state-specialized symbolic agents encode mechanistic transition priors, a multimodal neural transition model captures temporal and interaction dynamics, and uncertainty-aware epistemic fusion yields calibrated cluster-level transition distributions. Individual agents then stochastically realize transitions under local constraints, decoupling population inference from entity-level variability. We further introduce ANCHOR, an LLM agent-driven clustering strategy based on cross-contextual behavioral responses and a novel contrastive loss, reducing LLM calls by up to 6-8 times. Experiments across public health, finance, and social sciences show consistent gains in event-time accuracy and calibration over mechanistic, neural, and LLM baselines. By re-architecting generative ABM around population-level inference with uncertainty-aware neuro-symbolic fusion, PhysicsAgentABM establishes a new paradigm for scalable and calibrated simulation with LLMs.
cs.MM
[1159] Federated Prompt-Tuning with Heterogeneous and Incomplete Multimodal Client Data
Thu Hang Phung, Duong M. Nguyen, Thanh Trung Huynh, Quoc Viet Hung Nguyen, Trong Nghia Hoang, Phi Le Nguyen
Main category: cs.MM
TL;DR: A federated prompt-tuning framework for multi-modal data with missing features, enabling collaborative learning across distributed clients while handling modality-specific missing patterns.
Details
Motivation: Address the gap between federated learning and multi-modal prompt-tuning, which traditionally focus on either uni-modal or centralized data. Real-world scenarios involve distributed multi-modal datasets with different patterns of missing features across clients.Method: Proposes a generalized federated prompt-tuning framework with specialized client-tuning and server-aggregation designs that simultaneously optimize, align, and aggregate prompt-tuning instructions across clients and data modalities to handle missing feature patterns.
Result: Extensive evaluations on diverse multimodal benchmark datasets demonstrate consistent outperformance over state-of-the-art baselines.
Conclusion: The framework successfully bridges federated learning with multi-modal prompt-tuning, enabling effective collaborative learning in practical distributed multi-modal scenarios with missing features.
Abstract: This paper introduces a generalized federated prompt-tuning framework for practical scenarios where local datasets are multi-modal and exhibit different distributional patterns of missing features at the input level. The proposed framework bridges the gap between federated learning and multi-modal prompt-tuning which have traditionally focused on either uni-modal or centralized data. A key challenge in this setting arises from the lack of semantic alignment between prompt instructions that encode similar distributional patterns of missing data across different clients. To address this, our framework introduces specialized client-tuning and server-aggregation designs that simultaneously optimize, align, and aggregate prompt-tuning instructions across clients and data modalities. This allows prompt instructions to complement one another and be combined effectively. Extensive evaluations on diverse multimodal benchmark datasets demonstrate that our work consistently outperforms state-of-the-art (SOTA) baselines.
[1160] Stickers on Facebook: Multifunctionality and face-enhancing politeness in everyday social interaction
Laura M. Porrino-Moscoso
Main category: cs.MM
TL;DR: Analysis of sticker usage in Facebook comments during/after COVID-19, focusing on sociopragmatic functions and gender differences in digital politeness strategies.
Details
Motivation: Despite stickers' popularity in digital communication, most research has focused on emojis and emoticons, leaving a gap in understanding stickers' sociopragmatic functions, particularly in face-enhancing politeness during significant social periods like the COVID-19 pandemic.Method: Sociopragmatic analysis of sticker usage in Facebook comments from a corpus of posts containing face-enhancing politeness acts, collected during and after the COVID-19 pandemic, with consideration of gender variables.
Result: Identified six main functions of stickers: affective, illocutionary, interactional, gestural, aesthetic, and representative/substitutive. Found that stickers can intensify polite messages and express face-enhancing politeness autonomously. Gender differences observed: women use more stickers (especially cute/affectionate ones), while men prefer masculine human figures.
Conclusion: Stickers play a key multifunctional role in affective digital communication, serving as important tools for expressing politeness and emotional content in online interactions, with distinct gender-based usage patterns.
Abstract: Stickers are multimodal resources widely used in everyday digital conversations. Despite their popularity, most studies have focused on emojis and emoticons. Therefore, this study analyzes, from a sociopragmatic perspective, the use of stickers in the comments from a corpus of Facebook posts containing acts of face-enhancing politeness, created during and after the COVID-19 pandemic. The main objective is to identify their communicative functions and determine the extent to which they act as strategies of face-enhancing politeness also considering the gender variable. The results show a predominance of naked stickers and those representing human emotions and gestures, and festive situations. Six main functions were identified: affective, illocutionary, interactional, gestural, aesthetic, and representative or substitutive. It was found that stickers can intensify polite messages and express face-enhancing politeness autonomously. Furthermore, gender differences were observed: women use more stickers, especially cute and affectionate ones, whereas men prefer masculine human figures. These findings highlight the key and multifunctional role of stickers in affective digital communication.
[1161] T2VTree: User-Centered Visual Analytics for Agent-Assisted Thought-to-Video Authoring
Zhuoyun Zheng, Yu Dong, Gaorong Liang, Guan Li, Guihua Shan, Shiyu Cheng, Dong Tian, Jianlong Zhou, Jie Liang
Main category: cs.MM
TL;DR: T2VTree is a visual analytics system for agent-assisted thought-to-video authoring that represents the creative process as an editable tree visualization with collaborative AI agents.
Details
Motivation: Current video generation tools either hide intermediate decisions behind repeated reruns or expose operator-level workflows that make exploration traces difficult to manage, compare, and reuse, creating barriers for practical thought-to-video creation.Method: T2VTree uses a tree visualization where each node binds editable specifications (intent, inputs, workflow choices, prompts, parameters) with multimodal outputs. Collaborative AI agents translate step-level intent into executable plans that remain visible and editable before execution.
Result: The system enables end-to-end multi-scene creation without leaving the authoring context, supporting reliable refinement, localized comparison, and practical reuse in real authoring workflows as demonstrated through case studies and user studies.
Conclusion: T2VTree provides a user-centered visual analytics approach that makes the thought-to-video authoring process more manageable, comparable, and reusable through its tree visualization and editable agent planning system.
Abstract: Generative models have substantially expanded video generation capabilities, yet practical thought-to-video creation remains a multi-stage, multi-modal, and decision-intensive process. However, existing tools either hide intermediate decisions behind repeated reruns or expose operator-level workflows that make exploration traces difficult to manage, compare, and reuse. We present T2VTree, a user-centered visual analytics approach for agent-assisted thought-to-video authoring. T2VTree represents the authoring process as a tree visualization. Each node in the tree binds an editable specification (intent, referenced inputs, workflow choice, prompts, and parameters) with the resulting multimodal outputs, making refinement, branching, and provenance inspection directly operable. To reduce the burden of deciding what to do next, a set of collaborating agents translates step-level intent into an executable plan that remains visible and user-editable before execution. We further implement a visual analytics system that integrates branching authoring with in-place preview and stitching for convergent assembly, enabling end-to-end multi-scene creation without leaving the authoring context. We demonstrate T2VTreeVA through two multi-scene case studies and a comparative user study, showing how the T2VTree visualization and editable agent planning support reliable refinement, localized comparison, and practical reuse in real authoring workflows. T2VTree is available at: https://github.com/tezuka0210/T2VTree.
[1162] Lightweight Call Signaling and Peer-to-Peer Control of WebRTC Video Conferencing
Kundan Singh
Main category: cs.MM
TL;DR: A serverless, peer-to-peer web-based video conferencing system using WebRTC without media servers, leveraging push notifications or email for signaling.
Details
Motivation: To create a lightweight, cost-effective video conferencing solution that eliminates server dependencies and reduces maintenance costs for multiparty calls.Method: Uses WebRTC data channels and media streams for control and media paths, creates peer-to-peer network among clients, and employs push notifications or email for signaling without traditional media servers.
Result: A prototype web app that can be installed as browser extension or progressive web app, supporting full-featured video conferencing with audio, video, text, and screen sharing.
Conclusion: The serverless architecture and techniques developed are valuable for low-end WebRTC applications seeking to reduce server costs and dependencies for multiparty video calls.
Abstract: We present the software architecture and implementation of our web-based multiparty video conference application. It does not use a media server. For call signaling, it either piggybacks on existing push notifications via a lightweight notification server, or utilizes email messages to further remove that server dependency. For conference control and data storage, it creates a peer-to-peer network of the clients participating in the call. Our prototype client web app can be installed as a browser extension, or a progressive web app on desktop and mobile. It uses WebRTC data channels and media streams for the control and media paths in implementing a full featured video conferencing with audio, video, text and screen sharing. The challenges faced and the techniques used in creating our lightweight or serverless system are useful to other low-end WebRTC applications that intend to save cost on server maintenance or paid subscriptions for multiparty video calls.
eess.AS
[1163] SoulX-Singer: Towards High-Quality Zero-Shot Singing Voice Synthesis
Jiale Qian, Hao Meng, Tian Zheng, Pengcheng Zhu, Haopeng Lin, Yuhang Dai, Hanke Xie, Wenxiao Cao, Ruixuan Shang, Jun Wu, Hongmei Liu, Hanlin Wen, Jian Zhao, Zhonglin Jiang, Yong Chen, Shunshun Yin, Ming Tao, Jianguo Wei, Lei Xie, Xinsheng Wang
Main category: eess.AS
TL;DR: SoulX-Singer is an open-source singing voice synthesis system supporting multiple languages with strong zero-shot generalization capabilities, accompanied by a dedicated evaluation benchmark.
Details
Motivation: Addressing the lack of robust, production-ready open-source singing voice synthesis systems with good zero-shot generalization for industrial deployment.Method: Developed a high-quality SVS system trained on 42,000+ hours of vocal data, supporting Mandarin Chinese, English, and Cantonese, with conditioning on symbolic musical scores (MIDI) or melodic representations.
Result: Achieves state-of-the-art synthesis quality across languages under diverse musical conditions, with improved robustness and zero-shot generalization for practical deployment.
Conclusion: SoulX-Singer provides a production-ready open-source SVS solution with strong multilingual capabilities and zero-shot performance, accompanied by a dedicated evaluation benchmark for systematic assessment.
Abstract: While recent years have witnessed rapid progress in speech synthesis, open-source singing voice synthesis (SVS) systems still face significant barriers to industrial deployment, particularly in terms of robustness and zero-shot generalization. In this report, we introduce SoulX-Singer, a high-quality open-source SVS system designed with practical deployment considerations in mind. SoulX-Singer supports controllable singing generation conditioned on either symbolic musical scores (MIDI) or melodic representations, enabling flexible and expressive control in real-world production workflows. Trained on more than 42,000 hours of vocal data, the system supports Mandarin Chinese, English, and Cantonese and consistently achieves state-of-the-art synthesis quality across languages under diverse musical conditions. Furthermore, to enable reliable evaluation of zero-shot SVS performance in practical scenarios, we construct SoulX-Singer-Eval, a dedicated benchmark with strict training-test disentanglement, facilitating systematic assessment in zero-shot settings.
[1164] Detect, Attend and Extract: Keyword Guided Target Speaker Extraction
Haoyu Li, Yu Xi, Yidi Jiang, Shuai Wang, Kate Knill, Mark Gales, Haizhou Li, Kai Yu
Main category: eess.AS
TL;DR: DAE-TSE: A keyword-guided target speaker extraction framework that uses partial transcriptions instead of clean enrollment speech to identify and extract target speakers from speech mixtures.
Details
Motivation: Traditional target speaker extraction systems rely on clean enrollment utterances to identify target speakers, but these are often unavailable in real-world scenarios. The authors propose using keywords (partial transcriptions) as a more flexible and practical alternative to enrollment-based approaches.Method: DAE-TSE follows a Detect-Attend-Extract paradigm: 1) Detects the presence of given keywords in the speech mixture, 2) Attends to the corresponding speaker based on keyword content, 3) Extracts the target speech. This uses partial transcription as a cue instead of enrollment speech.
Result: Experimental results show DAE-TSE outperforms standard TSE systems that rely on clean enrollment speech. This represents the first study to utilize partial transcription as a cue for specifying target speakers in TSE.
Conclusion: The proposed keyword-guided TSE framework offers a flexible and practical solution for real-world scenarios where clean enrollment utterances are unavailable, demonstrating superior performance over enrollment-based approaches.
Abstract: Target speaker extraction (TSE) aims to extract the speech of a target speaker from mixtures containing multiple competing speakers. Conventional TSE systems predominantly rely on speaker cues, such as pre-enrolled speech, to identify and isolate the target speaker. However, in many practical scenarios, clean enrollment utterances are unavailable, limiting the applicability of existing approaches. In this work, we propose DAE-TSE, a keyword-guided TSE framework that specifies the target speaker through distinct keywords they utter. By leveraging keywords (i.e., partial transcriptions) as cues, our approach provides a flexible and practical alternative to enrollment-based TSE. DAE-TSE follows the Detect-Attend-Extract (DAE) paradigm: it first detects the presence of the given keywords, then attends to the corresponding speaker based on the keyword content, and finally extracts the target speech. Experimental results demonstrate that DAE-TSE outperforms standard TSE systems that rely on clean enrollment speech. To the best of our knowledge, this is the first study to utilize partial transcription as a cue for specifying the target speaker in TSE, offering a flexible and practical solution for real-world scenarios. Our code and demo page are now publicly available.
[1165] Cross-Modal Bottleneck Fusion For Noise Robust Audio-Visual Speech Recognition
Seaone Ok, Min Jun Choi, Eungbeom Kim, Seungu Han, Kyogu Lee
Main category: eess.AS
TL;DR: CoBRA introduces a bottleneck-based fusion framework using learnable tokens to mediate cross-modal exchange between audio and visual streams for robust audio-visual speech recognition under noisy conditions.
Details
Motivation: Current AVSR systems need better fusion mechanisms that can effectively exploit visual information when audio is degraded by noise, while maintaining performance on clean speech. The challenge is designing a fusion approach that works reliably under adverse or out-of-domain noise conditions.Method: Proposes CoBRA (Cross-modal Bottleneck for Robust AVSR), a bottleneck-based fusion framework that introduces a compact set of learnable tokens to mediate cross-modal exchange. These tokens regulate information flow, allowing the audio stream to access essential visual cues even under noisy conditions.
Result: Despite limited training data, CoBRA surpasses comparable baselines and remains competitive with large-scale systems through noise-adaptive fusion. Ablation studies show that the depth of fusion is the most critical factor for robust AVSR performance.
Conclusion: CoBRA demonstrates both efficiency and robustness in AVSR through its bottleneck-based fusion approach, highlighting the importance of fusion depth in designing robust multimodal speech recognition systems.
Abstract: Audio-Visual Speech Recognition (AVSR) leverages both acoustic and visual cues to improve speech recognition under noisy conditions. A central question is how to design a fusion mechanism that allows the model to effectively exploit visual information when the audio signal is degraded, while maintaining strong performance on clean speech. We propose CoBRA (Cross-modal Bottleneck for Robust AVSR), a bottleneck-based fusion framework that introduces a compact set of learnable tokens to mediate cross-modal exchange. By regulating information flow through these tokens, the audio stream can reliably access essential visual cues even under adverse or out-of-domain noise. Despite limited training data, our model surpasses comparable baselines and remains competitive with large-scale systems through noise-adaptive fusion, demonstrating both efficiency and robustness. Ablation studies highlight that the depth of fusion is the most critical factor, underscoring its importance in designing robust AVSR systems.
[1166] Physics-Guided Variational Model for Unsupervised Sound Source Tracking
Luan Vinícius Fiorio, Ivana Nikoloska, Bruno Defraene, Alex Young, Johan David, Ronald M. Aarts
Main category: eess.AS
TL;DR: Unsupervised variational model for sound source tracking using physics-based decoder, achieving performance comparable to supervised methods with robustness to array geometry changes.
Details
Motivation: Traditional sound source tracking uses classical array-processing or supervised ML requiring costly ground truth labels. Need for unsupervised methods that don't require labeled data.Method: Variational model performing single-source unsupervised sound source tracking in latent space with physics-based decoder. Extended to multi-source tracking with theoretical modifications.
Result: Method surpasses traditional baselines, achieves performance/complexity comparable to state-of-the-art supervised models, shows robustness to altered microphone array geometries and corrupted position metadata.
Conclusion: Proposed unsupervised variational approach is effective for sound source tracking without labeled data, robust to practical deployment challenges, and extensible to multi-source scenarios.
Abstract: Sound source tracking is often performed using classical array-processing algorithms. Alternative methods, such as machine learning, rely on ground truth position labels, which are costly to obtain. We propose a variational model that can perform single-source unsupervised sound source tracking in latent space, aided by a physics-based decoder. Our experiments demonstrate that the proposed method surpasses traditional baselines and achieves performance and computational complexity comparable to state-of-the-art supervised models. We also show that the method presents substantial robustness to altered microphone array geometries and corrupted microphone position metadata. Finally, the method is extended to multi-source sound tracking and the basic theoretical changes are proposed.
[1167] Input-Adaptive Spectral Feature Compression by Sequence Modeling for Source Separation
Kohei Saijo, Yoshiaki Bando
Main category: eess.AS
TL;DR: Spectral Feature Compression (SFC) replaces band-split modules in audio source separation with input-adaptive, parameter-efficient sequence modeling for frequency compression.
Details
Motivation: Band-split (BS) modules in time-frequency domain models have limitations: they're not input-adaptive (can't use input-dependent information) and have large parameter counts since each subband needs a dedicated module. These issues are particularly problematic for high-sampling-rate tasks like music and cinematic audio source separation.Method: Proposes Spectral Feature Compression (SFC) which compresses input using a single sequence modeling module (making it input-adaptive and parameter-efficient). Investigates two variants: one based on cross-attention and another on Mamba. Introduces inductive biases inspired by BS modules to make them suitable for frequency information compression.
Result: SFC consistently outperforms BS modules across different separator sizes and compression ratios on music source separation (MSS) and cinematic audio source separation (CASS) tasks. Analysis shows SFC adaptively captures frequency patterns from input.
Conclusion: SFC provides a superior alternative to BS modules for frequency compression in audio source separation, offering better performance with input-adaptivity and parameter efficiency.
Abstract: Time-frequency domain dual-path models have demonstrated strong performance and are widely used in source separation. Because their computational cost grows with the number of frequency bins, these models often use the band-split (BS) module in high-sampling-rate tasks such as music source separation (MSS) and cinematic audio source separation (CASS). The BS encoder compresses frequency information by encoding features for each predefined subband. It achieves effective compression by introducing an inductive bias that places greater emphasis on low-frequency parts. Despite its success, the BS module has two inherent limitations: (i) it is not input-adaptive, preventing the use of input-dependent information, and (ii) the parameter count is large, since each subband requires a dedicated module. To address these issues, we propose Spectral Feature Compression (SFC). SFC compresses the input using a single sequence modeling module, making it both input-adaptive and parameter-efficient. We investigate two variants of SFC, one based on cross-attention and the other on Mamba, and introduce inductive biases inspired by the BS module to make them suitable for frequency information compression. Experiments on MSS and CASS tasks demonstrate that the SFC module consistently outperforms the BS module across different separator sizes and compression ratios. We also provide an analysis showing that SFC adaptively captures frequency patterns from the input.
[1168] Pronunciation Editing for Finnish Speech using Phonetic Posteriorgrams
Zirui Li, Lauri Juvela, Mikko Kurimo
Main category: eess.AS
TL;DR: PPG2Speech: A diffusion-based model that edits native speech to approximate second-language (L2) speech by transforming Phonetic Posteriorgrams (PPGs) to mel-spectrograms, enabling phoneme-level editing without text alignment for low-resourced languages.
Details
Motivation: Synthesizing L2 speech is valuable for language learning but challenging due to lack of L2 speech datasets, especially for low-resourced languages. The paper aims to provide a practical solution for editing native speech to approximate L2 speech.Method: Uses a diffusion-based multispeaker Phonetic-Posteriorgrams-to-Speech model (PPG2Speech) with Matcha-TTS’s flow-matching decoder as backbone. Strengthens decoder with Classifier-free Guidance and Sway Sampling. Transforms PPGs to mel-spectrograms conditioned on speaker embeddings and pitch. Proposes Phonetic Aligned Consistency (PAC) metric for evaluation.
Result: Validated on Finnish (low-resourced, nearly phonetic language) using ~60 hours of data. Objective and subjective evaluations show effectiveness in naturalness, speaker similarity, and editing effectiveness compared to TTS-based editing.
Conclusion: PPG2Speech provides a practical solution for L2 speech synthesis by enabling phoneme-level editing without text alignment, particularly useful for low-resourced languages where L2 datasets are scarce.
Abstract: Synthesizing second-language (L2) speech is potentially highly valued for L2 language learning experience and feedback. However, due to the lack of L2 speech synthesis datasets, it is difficult to synthesize L2 speech for low-resourced languages. In this paper, we provide a practical solution for editing native speech to approximate L2 speech and present PPG2Speech, a diffusion-based multispeaker Phonetic-Posteriorgrams-to-Speech model that is capable of editing a single phoneme without text alignment. We use Matcha-TTS’s flow-matching decoder as the backbone, transforming Phonetic Posteriorgrams (PPGs) to mel-spectrograms conditioned on external speaker embeddings and pitch. PPG2Speech strengthens the Matcha-TTS’s flow-matching decoder with Classifier-free Guidance (CFG) and Sway Sampling. We also propose a new task-specific objective evaluation metric, the Phonetic Aligned Consistency (PAC), between the edited PPGs and the PPGs extracted from the synthetic speech for editing effects. We validate the effectiveness of our method on Finnish, a low-resourced, nearly phonetic language, using approximately 60 hours of data. We conduct objective and subjective evaluations of our approach to compare its naturalness, speaker similarity, and editing effectiveness with TTS-based editing. Our source code is published at https://github.com/aalto-speech/PPG2Speech.
[1169] Differentiable Grouped Feedback Delay Networks for Learning Coupled Volume Acoustics
Orchisama Das, Gloria Dal Santo, Sebastian J. Schlecht, Vesa Valimaki, Zoran Cvetkovic
Main category: eess.AS
TL;DR: Differentiable Grouped Feedback Delay Networks (DiffGFDNs) for efficient rendering of dynamic reverberation in coupled acoustic spaces, optimized to match measured room impulse responses with low computational cost.
Details
Motivation: Rendering dynamic reverberation for moving sources/listeners in XR applications is challenging due to high computational/memory costs of measured RIRs and difficulty in capturing spatially varying acoustic data. GFDNs offer efficiency but need parameter tuning for specific spaces.Method: Proposes DiffGFDNs with tunable parameters optimized to match late reverberation profiles of measured RIRs from multi-slope decay spaces. Uses parallel processing pipeline with multiple frequency-independent DiffGFDNs per octave band, enabling rapid parameter updates during inference.
Result: DiffGFDNs generate multi-slope late reverberation with lower memory/computational requirements than Common Slopes model, achieving better energy decay relief error and slightly worse octave-band energy decay curve errors, with order-of-magnitude fewer FLOPs per sample.
Conclusion: DiffGFDNs provide efficient, differentiable solution for dynamic reverberation rendering in XR applications, enabling real-time acoustic simulation for moving sources/listeners with practical computational demands.
Abstract: Rendering dynamic reverberation in a complicated acoustic space for moving sources and listeners is challenging but crucial for enhancing user immersion in extended-reality (XR) applications. Capturing spatially varying room impulse responses (RIRs) is costly and often impractical. Moreover, dynamic convolution with measured RIRs is computationally expensive with high memory demands, typically not available on wearable computing devices. Grouped Feedback Delay Networks (GFDNs), on the other hand, allow efficient rendering of coupled room acoustics. However, its parameters need to be tuned to match the reverberation profile of a coupled space. In this work, we propose the concept of Differentiable GFDNs (DiffGFDNs), which have tunable parameters that are optimised to match the late reverberation profile of a set of RIRs captured from a space that exhibits multi-slope decay. Once trained on a finite set of measurements, the DiffGFDN interpolates to unmeasured locations in the space. We propose a parallel processing pipeline that has multiple DiffGFDNs with frequency-independent parameters processing each octave band. The parameters of the DiffGFDN can be updated rapidly during inferencing as sources and listeners move. We evaluate the proposed architecture against the Common Slopes (CS) model on a dataset of RIRs for three coupled rooms. The proposed architecture generates multi-slope late reverberation with low memory and computational requirements, achieving a better energy decay relief (EDR) error and slightly worse octave-band energy decay curve (EDC) errors compared to the CS model. Furthermore, DiffGFDN requires an order of magnitude fewer floating-point operations per sample than the CS renderer.
[1170] Non-Intrusive Automatic Speech Recognition Refinement: A Survey
Mohammad Reza Peyghan, Saman Soleimani Roudi, Saeedreza Zouashkiani, Sajjad Amini, Fatemeh Rajabi, Shahrokh Ghaemmaghami
Main category: eess.AS
TL;DR: Survey paper reviewing non-intrusive refinement techniques for ASR systems, categorizing approaches into five classes and discussing domain adaptation, evaluation datasets, and future directions.
Details
Motivation: ASR systems struggle with speech variability (accents, dialects, noise) and domain-specific terminology, causing errors that propagate through NLP pipelines. Non-intrusive refinement techniques are needed as redesigning ASR models is costly.Method: Survey methodology categorizing non-intrusive ASR refinement approaches into five classes: fusion, re-scoring, correction, distillation, and training adjustment. Also reviews domain adaptation techniques, evaluation datasets, and proposes standardized metrics.
Result: Provides structured classification of refinement techniques with analysis of methods, advantages, drawbacks, and ideal application scenarios. Includes comprehensive review of adaptation techniques and evaluation resources.
Conclusion: Offers clear foundation for developing robust ASR refinement pipelines, identifies research gaps, and suggests future directions for improving ASR accuracy without architectural changes.
Abstract: Automatic Speech Recognition (ASR) has become an integral component of modern technology, powering applications such as voice-activated assistants, transcription services, and accessibility tools. Yet ASR systems continue to struggle with the inherent variability of human speech, such as accents, dialects, and speaking styles, as well as environmental interference, including background noise. Moreover, domain-specific conversations often employ specialized terminology, which can exacerbate transcription errors. These shortcomings not only degrade raw ASR accuracy but also propagate mistakes through subsequent natural language processing pipelines. Because redesigning an ASR model is costly and time-consuming, non-intrusive refinement techniques that leave the model’s architecture unchanged have become increasingly popular. In this survey, we review current non-intrusive refinement approaches and group them into five classes: fusion, re-scoring, correction, distillation, and training adjustment. For each class, we outline the main methods, advantages, drawbacks, and ideal application scenarios. Beyond method classification, this work surveys adaptation techniques aimed at refining ASR in domain-specific contexts, reviews commonly used evaluation datasets along with their construction processes, and proposes a standardized set of metrics to facilitate fair comparisons. Finally, we identify open research gaps and suggest promising directions for future work. By providing this structured overview, we aim to equip researchers and practitioners with a clear foundation for developing more robust, accurate ASR refinement pipelines.
[1171] Nord-Parl-TTS: Finnish and Swedish TTS Dataset from Parliament Speech
Zirui Li, Jens Edlund, Yicheng Gu, Nhan Phan, Lauri Juvela, Mikko Kurimo
Main category: eess.AS
TL;DR: Nord-Parl-TTS is an open text-to-speech dataset for Finnish and Swedish created from Nordic parliamentary proceedings, providing 900 hours of Finnish and 5090 hours of Swedish speech to address data scarcity for lower-resourced languages.
Details
Motivation: TTS development is limited by scarcity of high-quality, publicly available speech data for most languages outside a few high-resource languages. There's a significant resource gap between high-resource and lower-resourced languages in TTS.Method: Used recordings of Nordic parliamentary proceedings to extract speech data. Applied an adapted version of the Emilia data processing pipeline to create the dataset. Includes unified evaluation sets for benchmarking.
Result: Created Nord-Parl-TTS dataset with 900 hours of Finnish and 5090 hours of Swedish speech suitable for TTS training. The dataset is publicly available and includes evaluation sets for model development.
Conclusion: Nord-Parl-TTS narrows the resource gap in TTS between high- and lower-resourced languages by offering open, large-scale data for Finnish and Swedish, enabling better TTS development for these languages.
Abstract: Text-to-speech (TTS) development is limited by scarcity of high-quality, publicly available speech data for most languages outside a few high-resource languages. We present Nord-Parl-TTS, an open TTS dataset for Finnish and Swedish based on speech found in the wild. Using recordings of Nordic parliamentary proceedings, we extract 900 hours of Finnish and 5090 hours of Swedish speech suitable for TTS training. The dataset is built using an adapted version of the Emilia data processing pipeline and includes unified evaluation sets to support model development and benchmarking. By offering open, large-scale data for Finnish and Swedish, Nord-Parl-TTS narrows the resource gap in TTS between high- and lower-resourced languages.
[1172] Measuring Audio’s Impact on Correctness: Audio-Contribution-Aware Post-Training of Large Audio Language Models
Haolin He, Xingjian Du, Renhe Sun, Zheqi Dai, Yujia Xiao, Mingru Yang, Jiayi Zhou, Xiquan Li, Zhengxi Liu, Zining Liang, Chunyat Wu, Qianhua He, Tan Lee, Xie Chen, Wei-Long Zheng, Weiqiang Wang, Mark Plumbley, Jian Liu, Qiuqiang Kong
Main category: eess.AS
TL;DR: The paper introduces AudioMCQ, a large-scale audio multiple-choice question dataset with chain-of-thought annotations, and proposes novel post-training paradigms for Large Audio Language Models (LALMs) that address the zero audio-contribution phenomenon.
Details
Motivation: Current multi-stage post-training approaches for Large Audio Language Models (LALMs) remain suboptimal, with insufficient exploration of data allocation across training stages and a lack of large-scale, high-quality datasets. Additionally, there's a prevalent zero audio-contribution phenomenon where models answer correctly without processing audio content.Method: 1) Created AudioMCQ dataset with 571k audio multiple-choice questions and chain-of-thought annotations; 2) Proposed Audio-Contribution Filtering to partition data into weak and strong audio-contribution subsets; 3) Developed two post-training paradigms: Weak-to-Strong (SFT on weak audio-contribution data followed by RL on strong audio-contribution data) and Mixed-to-Strong (SFT on mixed audio-contribution data followed by RL on strong audio-contribution data).
Result: Achieved first place in DCASE 2025 Audio-Question-Answering challenge using AudioMCQ. Established new state-of-the-art performance: 78.2% on MMAU-test-mini, 75.6% on MMAU, 67.1% on MMAR, and 70.7% on MMSU.
Conclusion: The AudioMCQ dataset and proposed post-training paradigms effectively address data allocation challenges and the zero audio-contribution phenomenon in LALMs, leading to significant performance improvements across multiple audio understanding benchmarks.
Abstract: Large Audio Language Models (LALMs) represent an important frontier in multimodal AI, addressing diverse audio tasks. Recently, post-training of LALMs has received increasing attention due to significant performance improvements over foundation models. While single-stage post-training such as reinforcement learning (RL) has demonstrated promising results, multi-stage approaches such as supervised fine-tuning (SFT) followed by RL remain suboptimal. The allocation of data across multiple training stages to maximize LALM capabilities has not been fully explored, and large-scale, high-quality datasets for such research are also lacking. To address these problems, we firstly present AudioMCQ, a comprehensive audio multiple-choice question dataset comprising 571k samples with two kinds of chain-of-thought annotations. Secondly, we investigate the prevalent zero audio-contribution phenomenon in LALMs, where models derive correct answers solely from textual information without processing audio content. We propose Audio-Contribution Filtering to partition data into weak and strong audio-contribution subsets. Based on these insights, we develop two effective post-training paradigms: Weak-to-Strong (SFT on weak audio-contribution data followed by RL on strong audio-contribution data) and Mixed-to-Strong (SFT on mixed audio-contribution data followed by RL on strong audio-contribution data). We achieve first place in the DCASE 2025 Audio-Question-Answering challenge by using AudioMCQ. Additionally, leveraging our dataset with different training strategies, we achieve 78.2% on MMAU-test-mini, 75.6% on MMAU, 67.1% on MMAR, and 70.7% on MMSU, establishing new state-of-the-art performance.
[1173] The Combination of Several Decorrelation Methods to Improve Acoustic Feedback Cancellation
Klaus Linhard, Philipp Bulling
Main category: eess.AS
TL;DR: This paper enhances acoustic feedback cancellation by integrating multiple decorrelation techniques including variable time delay, prediction, distortion compensation, and simplified reverberation modeling into a frequency-domain Kalman filter framework.
Details
Motivation: Existing acoustic feedback cancellation systems often focus on single extensions like prediction, but the authors aim to demonstrate that combining multiple decorrelation methods can create a superior system with better performance.Method: Extends a baseline frequency-domain Kalman filter in multi-delay structure with four decorrelation methods: variable time delay line, prediction, distortion compensation, and simplified reverberation model. Each extension is analyzed individually and in combination.
Result: Each individual extension contributes to performance improvements, and the combination of all proposed extensions results in a superior system, validated using publicly available datasets with system distance metrics and PSEQ objective speech quality measure.
Conclusion: A comprehensive approach combining multiple decorrelation methods yields better acoustic feedback cancellation performance than systems focusing on single extensions, with practical parameter ranges defined for implementation.
Abstract: This paper extends an acoustic feedback cancellation system by incorporating multiple decorrelation methods. The baseline system is based on a frequency-domain Kalman filter implemented in a multi-delay structure. The proposed extensions include a variable time delay line, prediction, distortion compensation, and a simplified reverberation model. Each extension is analyzed, and a practical parameter range is defined. While existing literature often focuses on a single extension, such as prediction, to describe an optimal system, this work demonstrates that each individual extension contributes to performance improvements. Furthermore, the combination of all proposed extensions results in a superior system. The evaluation is conducted using publicly available datasets, with performance assessed through system distance metrics and the objective speech quality measure PSEQ.
eess.IV
[1174] Condition Errors Refinement in Autoregressive Image Generation with Diffusion Loss
Yucheng Zhou, Hao Li, Jianbing Shen
Main category: eess.IV
TL;DR: Theoretical analysis showing autoregressive diffusion models with diffusion loss outperform standard diffusion models by mitigating condition errors through patch denoising and condition refinement via Optimal Transport theory.
Details
Motivation: Recent work combines diffusion models with autoregressive frameworks using diffusion loss, but lacks theoretical understanding of why autoregressive diffusion performs better and how to address condition inconsistency issues.Method: Theoretical comparison of conditional diffusion vs autoregressive diffusion with diffusion loss, analysis of patch denoising optimization, and introduction of Optimal Transport-based condition refinement using Wasserstein Gradient Flow.
Result: Autoregressive diffusion models effectively mitigate condition errors, achieve stable condition distribution with exponential decay of condition error influence, and OT-based refinement converges to ideal condition distribution.
Conclusion: Autoregressive diffusion with diffusion loss and OT-based condition refinement theoretically and empirically outperforms standard diffusion and autoregressive diffusion methods.
Abstract: Recent studies have explored autoregressive models for image generation, with promising results, and have combined diffusion models with autoregressive frameworks to optimize image generation via diffusion losses. In this study, we present a theoretical analysis of diffusion and autoregressive models with diffusion loss, highlighting the latter’s advantages. We present a theoretical comparison of conditional diffusion and autoregressive diffusion with diffusion loss, demonstrating that patch denoising optimization in autoregressive models effectively mitigates condition errors and leads to a stable condition distribution. Our analysis also reveals that autoregressive condition generation refines the condition, causing the condition error influence to decay exponentially. In addition, we introduce a novel condition refinement approach based on Optimal Transport (OT) theory to address ``condition inconsistency’’. We theoretically demonstrate that formulating condition refinement as a Wasserstein Gradient Flow ensures convergence toward the ideal condition distribution, effectively mitigating condition inconsistency. Experiments demonstrate the superiority of our method over diffusion and autoregressive models with diffusion loss methods.
[1175] Guidestar-Free Adaptive Optics with Asymmetric Apertures
Weiyun Jiang, Haiyun Guo, Christopher A. Metzler, Ashok Veeraraghavan
Main category: eess.IV
TL;DR: First closed-loop adaptive optics system using asymmetric apertures and machine learning for real-time aberration correction without guidestar or wavefront sensor
Details
Motivation: To develop a guidestar-free adaptive optics system that can correct optical aberrations in real-time using computational methods rather than traditional wavefront sensorsMethod: Combines asymmetric apertures for phase retrieval, machine learning algorithms for PSF estimation from natural scenes and phase reconstruction, and spatial light modulator for optical correction
Result: Outperforms state-of-the-art guidestar-free wavefront shaping methods with order of magnitude fewer measurements and three orders of magnitude less computation
Conclusion: Demonstrates successful real-time aberration correction without guidestar or wavefront sensor using computational approach with asymmetric apertures and machine learning
Abstract: This work introduces the first closed-loop adaptive optics (AO) system capable of optically correcting aberrations in real-time without a guidestar or a wavefront sensor. Nearly 40 years ago, Cederquist et al. demonstrated that asymmetric apertures enable phase retrieval (PR) algorithms to perform fully computational wavefront sensing, albeit at a high computational cost. More recently, Chimitt et al. extended this approach with machine learning and demonstrated real-time wavefront sensing using only a single (guidestar-based) point-spread-function (PSF) measurement. Inspired by these works, we introduce a guidestar-free AO framework built around asymmetric apertures and machine learning. Our approach combines three key elements: (1) an asymmetric aperture placed in the optical path that enables PR-based wavefront sensing, (2) a pair of machine learning algorithms that estimate the PSF from natural scene measurements and reconstruct phase aberrations, and (3) a spatial light modulator that performs optical correction. We experimentally validate this framework on dense natural scenes imaged through unknown obscurants. Our method outperforms state-of-the-art guidestar-free wavefront shaping methods, using an order of magnitude fewer measurements and three orders of magnitude less computation.
[1176] MTS-CSNet: Multiscale Tensor Factorization for Deep Compressive Sensing on RGB Images
Mehmet Yamac, Lei Xu, Serkan Kiranyaz, Moncef Gabbouj
Main category: eess.IV
TL;DR: MTSCSNet: A compressive sensing framework using Multiscale Tensor Summation factorization for efficient high-dimensional signal processing with large receptive fields and cross-dimensional correlation modeling.
Details
Motivation: Existing deep learning compressive sensing methods use convolutional or block-wise fully connected layers that limit receptive fields and scale poorly for high-dimensional data, motivating a more efficient structured operator approach.Method: Proposes MTSCSNet using Multiscale Tensor Summation (MTS) factorization - a structured operator performing mode-wise linear transformations with multiscale summation for large receptive fields and cross-dimensional correlation modeling. MTS serves as both learnable CS operator for dimensionality reduction and in reconstruction stage to refine estimates.
Result: Achieves state-of-the-art reconstruction performance on RGB image CS benchmarks with notable PSNR gains and faster inference compared to recent methods including diffusion-based approaches, using a compact feed-forward architecture.
Conclusion: MTSCSNet demonstrates that structured tensor operators like MTS can enable efficient high-dimensional compressive sensing with large receptive fields, achieving superior performance with simpler architectures than iterative or diffusion-based methods.
Abstract: Deep learning based compressive sensing (CS) methods typically learn sampling operators using convolutional or block wise fully connected layers, which limit receptive fields and scale poorly for high dimensional data. We propose MTSCSNet, a CS framework based on Multiscale Tensor Summation (MTS) factorization, a structured operator for efficient multidimensional signal processing. MTS performs mode-wise linear transformations with multiscale summation, enabling large receptive fields and effective modeling of cross-dimensional correlations. In MTSCSNet, MTS is first used as a learnable CS operator that performs linear dimensionality reduction in tensor space, with its adjoint defining the initial back-projection, and is then applied in the reconstruction stage to directly refine this estimate. This results in a simple feed-forward architecture without iterative or proximal optimization, while remaining parameter and computation efficient. Experiments on standard CS benchmarks show that MTSCSNet achieves state-of-the-art reconstruction performance on RGB images, with notable PSNR gains and faster inference, even compared to recent diffusion-based CS methods, while using a significantly more compact feed-forward architecture.
[1177] U-Net Based Image Enhancement for Short-time Muon Scattering Tomography
Haochen Wang, Pei Yu, Liangwen Chen, Weibo He, Yu Zhang, Yuhong Yu, Xueheng Zhang, Lei Yang, Zhiyu Sun
Main category: eess.IV
TL;DR: U-Net framework trained on simulated PoCA images enhances low-quality muon scattering tomography images, improving SSIM from 0.723 to 0.970 and reducing LPIPS from 0.360 to 0.027.
Details
Motivation: Short-time Muon Scattering Tomography suffers from poor image quality due to limited muon flux, hindering practical applications. Need to enhance low-statistics MST images for real-world deployment.Method: Propose U-Net-based framework trained on simulated Point of Closest Approach (PoCA) images to enhance image quality. Use simulation MST data to train model, then apply to experimental MST data.
Result: Framework significantly improves image quality: SSIM increases from 0.7232 to 0.9699, LPIPS decreases from 0.3604 to 0.0270. Demonstrates effective enhancement of low-statistics MST images.
Conclusion: Method effectively enhances low-statistics MST images, enabling practical deployment of short-time Muon Scattering Tomography for non-invasive inspection applications.
Abstract: Muon Scattering Tomography (MST) is a promising non-invasive inspection technique, yet the practical application of short-time MST is hindered by poor image quality due to limited muon flux. To address this limitation, we propose a U-Net-based framework trained on Point of Closest Approach (PoCA) images reconstructed with simulation MST data to enhance image quality. When applied to experimental MST data, the framework significantly improves image quality, increasing the Structural Similarity Index Measure (SSIM) from 0.7232 to 0.9699 and decreasing the Learned Perceptual Image Patch Similarity (LPIPS) from 0.3604 to 0.0270. These results demonstrate that our method can effectively enhance low-statistics MST images, thereby paving the way for the practical deployment of short-time MST.
[1178] Surveillance Facial Image Quality Assessment: A Multi-dimensional Dataset and Lightweight Model
Yanwei Jiang, Wei Sun, Yingjie Zhou, Xiangyang Zhu, Yuqin Cao, Jun Jia, Yunhao Li, Sijing Wu, Dandan Zhu, Xingkuo Min, Guangtao Zhai
Main category: eess.IV
TL;DR: Proposes SFIQA-Bench benchmark and SFIQA-Assessor model for surveillance facial image quality assessment, jointly evaluating visual quality and identity fidelity for surveillance applications.
Details
Motivation: Surveillance facial images suffer from quality degradation (low resolution, blur, occlusion, poor lighting), and existing restoration techniques often compromise identity fidelity. Current FIQA methods focus on either visual quality or recognition, but not both jointly, which is critical for surveillance where reliable identity verification is the primary objective.Method: 1) Constructs SFIQA-Bench benchmark with 5,004 surveillance facial images from three real-world surveillance cameras, collecting six-dimensional quality ratings (noise, sharpness, colorfulness, contrast, fidelity, overall quality) through subjective experiments. 2) Proposes SFIQA-Assessor, a lightweight multi-task FIQA model that uses cross-view feature interaction between complementary facial views and learnable task tokens for unified regression of multiple quality dimensions.
Result: The proposed SFIQA-Assessor achieves state-of-the-art performance on the SFIQA-Bench dataset compared to existing general IQA and FIQA methods, validating its effectiveness for real-world surveillance applications.
Conclusion: This is the first comprehensive study on surveillance facial image quality assessment (SFIQA), addressing the unique challenges of surveillance scenarios by jointly considering visual quality and identity fidelity. The proposed benchmark and model provide effective tools for evaluating and improving surveillance facial image quality.
Abstract: Surveillance facial images are often captured under unconstrained conditions, resulting in severe quality degradation due to factors such as low resolution, motion blur, occlusion, and poor lighting. Although recent face restoration techniques applied to surveillance cameras can significantly enhance visual quality, they often compromise fidelity (i.e., identity-preserving features), which directly conflicts with the primary objective of surveillance images – reliable identity verification. Existing facial image quality assessment (FIQA) predominantly focus on either visual quality or recognition-oriented evaluation, thereby failing to jointly address visual quality and fidelity, which are critical for surveillance applications. To bridge this gap, we propose the first comprehensive study on surveillance facial image quality assessment (SFIQA), targeting the unique challenges inherent to surveillance scenarios. Specifically, we first construct SFIQA-Bench, a multi-dimensional quality assessment benchmark for surveillance facial images, which consists of 5,004 surveillance facial images captured by three widely deployed surveillance cameras in real-world scenarios. A subjective experiment is conducted to collect six dimensional quality ratings, including noise, sharpness, colorfulness, contrast, fidelity and overall quality, covering the key aspects of SFIQA. Furthermore, we propose SFIQA-Assessor, a lightweight multi-task FIQA model that jointly exploits complementary facial views through cross-view feature interaction, and employs learnable task tokens to guide the unified regression of multiple quality dimensions. The experiment results on the proposed dataset show that our method achieves the best performance compared with the state-of-the-art general image quality assessment (IQA) and FIQA methods, validating its effectiveness for real-world surveillance applications.
[1179] MRI Cross-Modal Synthesis: A Comparative Study of Generative Models for T1-to-T2 Reconstruction
Ali Alqutayfi, Sadam Al-Azani
Main category: eess.IV
TL;DR: Comparative study of three generative models (Pix2Pix GAN, CycleGAN, VAE) for T1-to-T2 MRI synthesis using BraTS 2020 dataset, with CycleGAN achieving best PSNR/SSIM and Pix2Pix GAN best MSE.
Details
Motivation: MRI cross-modal synthesis reduces scan time while maintaining diagnostic information, offering clinical value. Need to compare state-of-the-art generative models for T1-to-T2 MRI reconstruction to guide researchers and clinicians in model selection.Method: Comprehensive comparison of Pix2Pix GAN, CycleGAN, and Variational Autoencoder (VAE) using BraTS 2020 dataset (11,439 training and 2,000 testing slices). Evaluation based on MSE, PSNR, and SSIM metrics.
Result: All models successfully synthesize T2 images from T1 inputs. CycleGAN achieved highest PSNR (32.28 dB) and SSIM (0.9008). Pix2Pix GAN provided lowest MSE (0.005846). VAE showed lower quantitative performance (MSE: 0.006949, PSNR: 24.95 dB, SSIM: 0.6573) but offers latent space advantages.
Conclusion: Comparative study provides insights for selecting appropriate generative models for MRI synthesis based on specific requirements and data constraints, with CycleGAN performing best overall for T1-to-T2 conversion.
Abstract: MRI cross-modal synthesis involves generating images from one acquisition protocol using another, offering considerable clinical value by reducing scan time while maintaining diagnostic information. This paper presents a comprehensive comparison of three state-of-the-art generative models for T1-to-T2 MRI reconstruction: Pix2Pix GAN, CycleGAN, and Variational Autoencoder (VAE). Using the BraTS 2020 dataset (11,439 training and 2,000 testing slices), we evaluate these models based on established metrics including Mean Squared Error (MSE), Peak Signal-to-Noise Ratio (PSNR), and Structural Similarity Index (SSIM). Our experiments demonstrate that all models can successfully synthesize T2 images from T1 inputs, with CycleGAN achieving the highest PSNR (32.28 dB) and SSIM (0.9008), while Pix2Pix GAN provides the lowest MSE (0.005846). The VAE, though showing lower quantitative performance (MSE: 0.006949, PSNR: 24.95 dB, SSIM: 0.6573), offers advantages in latent space representation and sampling capabilities. This comparative study provides valuable insights for researchers and clinicians selecting appropriate generative models for MRI synthesis applications based on their specific requirements and data constraints.
[1180] Exploring Polarimetric Properties Preservation during Reconstruction of PolSAR images using Complex-valued Convolutional Neural Networks
Quentin Gabot, Joana Frontera-Pons, Jérémy Fix, Chengfang Ren, Jean-Philippe Ovarlez
Main category: eess.IV
TL;DR: Complex-valued neural networks outperform real-valued models for processing polarimetric SAR data by preserving essential physical characteristics through various decompositions.
Details
Motivation: Polarimetric SAR data is inherently complex-valued, but most deep learning approaches convert it to real domain before processing, losing important physical information. The paper aims to explore specialized complex-valued algorithms that can directly process complex representations.Method: The authors leverage complex-valued neural networks, specifically complex-valued Convolutional AutoEncoders, to compress and reconstruct fully polarimetric SAR data while preserving physical characteristics through Pauli, Krogager, Cameron coherent decompositions, and non-coherent H-α decomposition.
Result: Complex-valued neural networks effectively compress and reconstruct polarimetric SAR data while preserving essential physical characteristics. They demonstrate advantages over real-valued counterparts in maintaining the integrity of complex signal representations.
Conclusion: Complex-valued neural networks are superior for processing complex-valued SAR data and pave the way for developing robust, physics-informed, complex-valued generative models for SAR data processing.
Abstract: The inherently complex-valued nature of Polarimetric SAR data necessitates using specialized algorithms capable of directly processing complex-valued representations. However, this aspect remains underexplored in the deep learning community, with many studies opting to convert complex signals into the real domain before applying conventional real-valued models. In this work, we leverage complex-valued neural networks and investigate the performance of complex-valued Convolutional AutoEncoders. We show that these networks can effectively compress and reconstruct fully polarimetric SAR data while preserving essential physical characteristics, as demonstrated through Pauli, Krogager, and Cameron coherent decompositions, as well as the non-coherent $H-α$ decomposition. Finally, we highlight the advantages of complex-valued neural networks over their real-valued counterparts. These insights pave the way for developing robust, physics-informed, complex-valued generative models for SAR data processing.
[1181] DEMIX: Dual-Encoder Latent Masking Framework for Mixed Noise Reduction in Ultrasound Imaging
Soumee Guha, Scott T. Acton
Main category: eess.IV
TL;DR: DEMIX: A dual-encoder denoising framework with masked gated fusion for ultrasound image restoration, handling mixed noise and PSF-induced distortions using diffusion-inspired approach.
Details
Motivation: Ultrasound imaging suffers from signal-dependent speckle noise, sensor noise, and PSF-induced blurring that degrade image quality. Conventional methods assume simplified noise models and struggle with these complex degradations, creating need for specialized algorithms that can reduce noise while preserving structural details.Method: Proposes DEMIX, a dual-encoder denoising framework with masked gated fusion mechanism. Inspired by diffusion models with forward and deterministic reverse processes. Adaptively assesses different noise components, disentangles them in latent space, and suppresses noise while compensating for PSF degradations.
Result: Extensive experiments on two ultrasound datasets show DEMIX consistently outperforms state-of-the-art baselines, achieving superior noise suppression and preserving structural details. Also demonstrates effectiveness in downstream segmentation task.
Conclusion: DEMIX effectively addresses mixed noise and PSF-induced distortions in ultrasound imaging, outperforming existing methods and showing practical utility in medical diagnostics through improved image quality and segmentation performance.
Abstract: Ultrasound imaging is widely used in noninvasive medical diagnostics due to its efficiency, portability, and avoidance of ionizing radiation. However, its utility is limited by the quality of the signal. Signal-dependent speckle noise, signal-independent sensor noise, and non-uniform spatial blurring caused by the transducer and modeled by the point spread function (PSF) degrade the image quality. These degradations challenge conventional image restoration methods, which assume simplified noise models, and highlight the need for specialized algorithms capable of effectively reducing the degradations while preserving fine structural details. We propose DEMIX, a novel dual-encoder denoising framework with a masked gated fusion mechanism, for denoising ultrasound images degraded by mixed noise and further degraded by PSF-induced distortions. DEMIX is inspired by diffusion models and is characterized by a forward process and a deterministic reverse process. DEMIX adaptively assesses the different noise components, disentangles them in the latent space, and suppresses these components while compensating for PSF degradations. Extensive experiments on two ultrasound datasets, along with a downstream segmentation task, demonstrate that DEMIX consistently outperforms state-of-the-art baselines, achieving superior noise suppression and preserving structural details. The code will be made publicly available.
[1182] Information Theory: An X-ray Microscopy Perspective
Charles Wood
Main category: eess.IV
TL;DR: The paper analyzes X-ray microscopy workflows as information-processing systems using information theory metrics to quantify how various stages (acquisition, denoising, alignment, sparse sampling, dose variation, reconstruction) reshape statistical structure and impose information bottlenecks.
Details
Motivation: X-ray microscopy workflows introduce noise, redundancy, and information loss at multiple stages, but there's a lack of quantitative understanding of how these processes affect information flow and impose bottlenecks in the imaging pipeline.Method: Treats XRM workflow as an information-processing system using entropy, mutual information, and Kullback-Leibler divergence to quantify how acquisition, denoising, alignment, sparse-angle sampling, dose variation, and reconstruction reshape statistical structure of projection data and reconstructed volumes.
Result: Case studies using the Walnut 1 dataset show how these processes redistribute information and impose bottlenecks; mutual information provides a reconstruction-agnostic indicator of fidelity, supporting quantitative comparison and optimization of XRM protocols.
Conclusion: Information theory provides a unified framework for analyzing XRM workflows, with mutual information serving as a valuable metric for protocol optimization, especially under low-dose or time-constrained conditions.
Abstract: X-ray microscopy (XRM) is commonly used to obtain three-dimensional information on internal microstructure, but the imaging pipeline introduces noise, redundancy and information loss at multiple stages. This paper treats the XRM workflow as an information-processing system acting on a finite information budget. Using entropy, mutual information and Kullback-Leibler divergence, we quantify how acquisition, denoising, alignment, sparse-angle sampling, dose variation and reconstruction reshape the statistical structure of projection data and reconstructed volumes. Case studies based on the Walnut 1 dataset illustrate how these processes redistribute information and impose bottlenecks. We summarise the workflow using a unified information budget and show that mutual information provides a reconstruction-agnostic indicator of fidelity, supporting quantitative comparison and optimisation of XRM protocols, particularly under low-dose or time-constrained conditions
[1183] Extracting Root-Causal Brain Activity Driving Psychopathology from Resting State fMRI
Eric V. Strobl
Main category: eess.IV
TL;DR: SOURCE method identifies localized root-causal BOLD disturbances in fMRI that drive specific symptom dimensions in psychiatric disorders, improving interpretability over traditional correlation approaches.
Details
Motivation: Traditional neuroimaging studies correlate imaging patterns with diagnostic labels or symptom scores, producing diffuse associations that obscure underlying mechanisms. The authors aim to identify root-causal maps - localized BOLD disturbances that initiate pathological cascades - and link them selectively to specific symptom dimensions.Method: Introduce a bilevel structural causal model connecting between-subject symptom structure to within-subject resting-state fMRI via independent latent sources with localized direct effects. Develop SOURCE (Symptom-Oriented Uncovering of Root-Causal Elements) procedure that links interpretable symptom axes to a parsimonious set of localized drivers.
Result: Experiments show that SOURCE recovers localized maps consistent with root-causal BOLD drivers and increases interpretability and anatomical specificity relative to existing comparators.
Conclusion: SOURCE provides a framework for identifying localized neural drivers of specific psychiatric symptoms, moving beyond diffuse correlations to causal mechanisms with improved anatomical specificity.
Abstract: Neuroimaging studies of psychiatric disorders often correlate imaging patterns with diagnostic labels or composite symptom scores, yielding diffuse associations that obscure underlying mechanisms. We instead seek to identify root-causal maps – localized BOLD disturbances that initiate pathological cascades – and to link them selectively to symptom dimensions. We introduce a bilevel structural causal model that connects between-subject symptom structure to within-subject resting-state fMRI via independent latent sources with localized direct effects. Based on this model, we develop SOURCE (Symptom-Oriented Uncovering of Root-Causal Elements), a procedure that links interpretable symptom axes to a parsimonious set of localized drivers. Experiments show that SOURCE recovers localized maps consistent with root-causal BOLD drivers and increases interpretability and anatomical specificity relative to existing comparators.
[1184] Transform and Entropy Coding in AV2
Alican Nalci, Hilmi E. Egilmez, Madhu P. Krishnan, Keng-Shih Lu, Joe Young, Debargha Mukherjee, Lin Zheng, Jingning Han, Joel Sole, Xiaoqing Zhu, Xin Zhao, Tianqi Liu, Liang Zhao, Todd Nguyen, Urvang Joshi, Kruthika Koratti Sivakumar, Luhang Xu, Zhijun Lei, Van Luong Pham, Yue Yu, Aki Kuusela, Minhua Zhou, Andrey Norkin, Adrian Grange
Main category: eess.IV
TL;DR: AV2 is the next-generation video coding standard from AOMedia that achieves significant compression gains and quality improvements through redesigned transform kernels, expanded partitioning, and new coding tools like secondary transforms and trellis coded quantization.
Details
Motivation: To create a successor to AV1 that delivers substantial compression improvements and subjective quality enhancements while maintaining low-complexity encoding and decoding operations for practical video applications.Method: AV2 introduces redesigned transform kernels, data-driven transforms, expanded transform partitioning, and mode/coefficient dependent transform signaling. New coding tools include Intra/Inter Secondary Transforms (IST), Trellis Coded Quantization (TCQ), Adaptive Transform Coding (ATC), Probability Adaptation Rate Adjustment (PARA), Forward Skip Coding (FSC), Cross Chroma Component Transforms (CCTX), Parity Hiding (PH) tools, and improved lossless coding.
Result: AV2 delivers the highest quality video experience for video applications at significantly reduced bitrates compared to previous standards.
Conclusion: AV2 represents a major advancement in video compression technology, achieving substantial quality improvements and bitrate reductions through innovative transform, quantization, and entropy coding designs while maintaining practical computational complexity.
Abstract: AV2 is the successor to the AV1 video coding standard developed by the Alliance for Open Media (AOMedia). Its primary objective is to deliver substantial compression gains and subjective quality improvements while maintaining low-complexity encoder and decoder operations. This paper describes the transform, quantization and entropy coding design in AV2, including redesigned transform kernels and data-driven transforms, expanded transform partitioning, and a mode & coefficient dependent transform signaling. AV2 introduces several new coding tools including Intra/Inter Secondary Transforms (IST), Trellis Coded Quantization (TCQ), Adaptive Transform Coding (ATC), Probability Adaptation Rate Adjustment (PARA), Forward Skip Coding (FSC), Cross Chroma Component Transforms (CCTX), Parity Hiding (PH) tools and improved lossless coding. These advances enable AV2 to deliver the highest quality video experience for video applications at a significantly reduced bitrate.
[1185] Wavelet-Domain Masked Image Modeling for Color-Consistent HDR Video Reconstruction
Yang Zhang, Zhangkai Ni, Wenhan Yang, Hanli Wang
Main category: eess.IV
TL;DR: WMNet: A novel HDR video reconstruction network using wavelet domain masked image modeling and temporal modules for improved color accuracy and temporal consistency.
Details
Motivation: Existing HDR video reconstruction methods suffer from color inaccuracies and temporal inconsistencies, limiting their practical application for recovering fine brightness, color, and details from LDR videos.Method: Two-phase training: Phase I uses wavelet domain masked image modeling (W-MIM) for self-reconstruction pre-training with curriculum learning; Phase II fine-tunes. Temporal consistency achieved via Temporal Mixture of Experts (T-MoE) and Dynamic Memory Module (DMM). Also reorganizes HDRTV4K into HDRTV4K-Scene benchmark.
Result: WMNet achieves state-of-the-art performance across multiple evaluation metrics, significantly improving color fidelity, temporal coherence, and perceptual quality compared to existing methods.
Conclusion: WMNet effectively addresses color accuracy and temporal consistency challenges in HDR video reconstruction through wavelet domain pre-training and temporal fusion modules, establishing a new benchmark for the field.
Abstract: High Dynamic Range (HDR) video reconstruction aims to recover fine brightness, color, and details from Low Dynamic Range (LDR) videos. However, existing methods often suffer from color inaccuracies and temporal inconsistencies. To address these challenges, we propose WMNet, a novel HDR video reconstruction network that leverages Wavelet domain Masked Image Modeling (W-MIM). WMNet adopts a two-phase training strategy: In Phase I, W-MIM performs self-reconstruction pre-training by selectively masking color and detail information in the wavelet domain, enabling the network to develop robust color restoration capabilities. A curriculum learning scheme further refines the reconstruction process. Phase II fine-tunes the model using the pre-trained weights to improve the final reconstruction quality. To improve temporal consistency, we introduce the Temporal Mixture of Experts (T-MoE) module and the Dynamic Memory Module (DMM). T-MoE adaptively fuses adjacent frames to reduce flickering artifacts, while DMM captures long-range dependencies, ensuring smooth motion and preservation of fine details. Additionally, since existing HDR video datasets lack scene-based segmentation, we reorganize HDRTV4K into HDRTV4K-Scene, establishing a new benchmark for HDR video reconstruction. Extensive experiments demonstrate that WMNet achieves state-of-the-art performance across multiple evaluation metrics, significantly improving color fidelity, temporal coherence, and perceptual quality. The code is available at: https://github.com/eezkni/WMNet
[1186] DINO-Mix: Distilling Foundational Knowledge with Cross-Domain CutMix for Semi-supervised Class-imbalanced Medical Image Segmentation
Xinyu Liu, Guolei Sun
Main category: eess.IV
TL;DR: DINO-Mix: A semi-supervised medical image segmentation framework using foundational knowledge distillation from DINOv3 and progressive imbalance-aware data augmentation to address class imbalance issues.
Details
Motivation: Current SSL frameworks for medical image segmentation are "inward-looking" and suffer from confirmation bias under class imbalance, leading to catastrophic failure on minority classes. The paper aims to break this vicious cycle by looking outward for unbiased knowledge.Method: Proposes DINO-Mix framework with two key components: 1) Foundational Knowledge Distillation (FKD) using pre-trained DINOv3 as an unbiased external semantic teacher, and 2) Progressive Imbalance-aware CutMix (PIC) that creates a dynamic curriculum forcing focus on minority classes in both labeled and unlabeled data.
Result: Achieves remarkable performance on challenging semi-supervised class-imbalanced medical image segmentation benchmarks Synapse and AMOS, demonstrating effectiveness in handling minority classes.
Conclusion: The outward-looking paradigm with foundational knowledge distillation and progressive imbalance-aware augmentation successfully breaks the vicious cycle of bias in SSL for medical image segmentation, enabling robust performance on minority classes.
Abstract: Semi-supervised learning (SSL) has emerged as a critical paradigm for medical image segmentation, mitigating the immense cost of dense annotations. However, prevailing SSL frameworks are fundamentally “inward-looking”, recycling information and biases solely from within the target dataset. This design triggers a vicious cycle of confirmation bias under class imbalance, leading to the catastrophic failure to recognize minority classes. To dismantle this systemic issue, we propose a paradigm shift to a multi-level “outward-looking” framework. Our primary innovation is Foundational Knowledge Distillation (FKD), which looks outward beyond the confines of medical imaging by introducing a pre-trained visual foundation model, DINOv3, as an unbiased external semantic teacher. Instead of trusting the student’s biased high confidence, our method distills knowledge from DINOv3’s robust understanding of high semantic uniqueness, providing a stable, cross-domain supervisory signal that anchors the learning of minority classes. To complement this core strategy, we further look outward within the data by proposing Progressive Imbalance-aware CutMix (PIC), which creates a dynamic curriculum that adaptively forces the model to focus on minority classes in both labeled and unlabeled subsets. This layered strategy forms our framework, DINO-Mix, which breaks the vicious cycle of bias and achieves remarkable performance on challenging semi-supervised class-imbalanced medical image segmentation benchmarks Synapse and AMOS.
[1187] A Unified Framework for Multimodal Image Reconstruction and Synthesis using Denoising Diffusion Models
Weijie Gan, Xucheng Wang, Tongyao Wang, Wenshang Wang, Chunwei Ying, Yuyang Hu, Yasheng Chen, Hongyu An, Ulugbek S. Kamilov
Main category: eess.IV
TL;DR: Any2all is a unified framework that treats multimodal image reconstruction and synthesis as virtual inpainting problems using a single unconditional diffusion model trained on complete multimodal data.
Details
Motivation: Existing methods require multiple task-specific models for handling incomplete multimodal imaging data, which complicates training and deployment workflows. There's a need for a unified approach.Method: Formulates multimodal reconstruction and synthesis as a single virtual inpainting problem. Trains a single unconditional diffusion model on complete multimodal data stack, then adapts it at inference to inpaint target modalities from any combination of available inputs (clean images or noisy measurements).
Result: Validated on PET/MR/CT brain dataset. Achieves excellent performance on both multimodal reconstruction and synthesis tasks, with competitive distortion-based performance and superior perceptual quality over specialized methods.
Conclusion: Any2all provides a unified framework that simplifies multimodal imaging workflows while maintaining or improving performance compared to task-specific approaches.
Abstract: Image reconstruction and image synthesis are important for handling incomplete multimodal imaging data, but existing methods require various task-specific models, complicating training and deployment workflows. We introduce Any2all, a unified framework that addresses this limitation by formulating these disparate tasks as a single virtual inpainting problem. We train a single, unconditional diffusion model on the complete multimodal data stack. This model is then adapted at inference time to ``inpaint’’ all target modalities from any combination of inputs of available clean images or noisy measurements. We validated Any2all on a PET/MR/CT brain dataset. Our results show that Any2all can achieve excellent performance on both multimodal reconstruction and synthesis tasks, consistently yielding images with competitive distortion-based performance and superior perceptual quality over specialized methods.
[1188] Trajectory Stitching for Solving Inverse Problems with Flow-Based Models
Alexander Denker, Moshe Eliasof, Zeljko Kereta, Carola-Bibiane Schönlieb
Main category: eess.IV
TL;DR: MS-Flow: A memory-efficient flow-based generative model for inverse problems using intermediate latent states instead of single initial noise optimization
Details
Motivation: Existing flow-based generative models for inverse problems require optimizing a single initial latent code, which necessitates backpropagation through the entire generative trajectory, leading to high memory costs and numerical instability.Method: MS-Flow represents the generative trajectory as a sequence of intermediate latent states rather than a single initial code. It enforces flow dynamics locally and couples segments through trajectory-matching penalties, alternating between updating intermediate latent states and enforcing consistency with observed data.
Result: MS-Flow reduces memory consumption while improving reconstruction quality compared to existing methods. Demonstrated effectiveness on image recovery tasks including inpainting, super-resolution, and computed tomography.
Conclusion: MS-Flow provides a more efficient and stable approach for using flow-based generative models as priors for solving inverse problems by optimizing intermediate latent states rather than a single initial latent code.
Abstract: Flow-based generative models have emerged as powerful priors for solving inverse problems. One option is to directly optimize the initial latent code (noise), such that the flow output solves the inverse problem. However, this requires backpropagating through the entire generative trajectory, incurring high memory costs and numerical instability. We propose MS-Flow, which represents the trajectory as a sequence of intermediate latent states rather than a single initial code. By enforcing the flow dynamics locally and coupling segments through trajectory-matching penalties, MS-Flow alternates between updating intermediate latent states and enforcing consistency with observed data. This reduces memory consumption while improving reconstruction quality. We demonstrate the effectiveness of MS-Flow over existing methods on image recovery and inverse problems, including inpainting, super-resolution, and computed tomography.
[1189] Efficient Brain Extraction of MRI Scans with Mild to Moderate Neuropathology
Hjalti Thrastarson, Lotta M. Ellingsen
Main category: eess.IV
TL;DR: A novel skull stripping method for brain MRI using modified U-net with signed-distance transform loss function, achieving robust brain extraction with consistent outer surface preservation.
Details
Motivation: Existing skull stripping methods for brain MRI often fail with neuropathology and inconsistently define brain boundaries, particularly struggling with sulcal CSF inclusion and subarachnoid space exclusion.Method: Modified U-net architecture trained on silver-standard ground truth using novel loss function based on signed-distance transform (SDT) for robust brain boundary segmentation.
Result: Achieved consistent mean Dice similarity coefficient of 0.964±0.006 and average symmetric surface distance of 1.4mm±0.2mm on held-out test data, with comparable performance (0.958±0.006 DSC, 1.7±0.2mm ASSD) on external dataset.
Conclusion: The method provides robust and efficient skull stripping with superior boundary consistency compared to existing methods, particularly in preserving the brain’s outer surface while excluding subarachnoid space.
Abstract: Skull stripping magnetic resonance images (MRI) of the human brain is an important process in many image processing techniques, such as automatic segmentation of brain structures. Numerous methods have been developed to perform this task, however, they often fail in the presence of neuropathology and can be inconsistent in defining the boundary of the brain mask. Here, we propose a novel approach to skull strip T1-weighted images in a robust and efficient manner, aiming to consistently segment the outer surface of the brain, including the sulcal cerebrospinal fluid (CSF), while excluding the full extent of the subarachnoid space and meninges. We train a modified version of the U-net on silver-standard ground truth data using a novel loss function based on the signed-distance transform (SDT). We validate our model both qualitatively and quantitatively using held-out data from the training dataset, as well as an independent external dataset. The brain masks used for evaluation partially or fully include the subarachnoid space, which may introduce bias into the comparison; nonetheless, our model demonstrates strong performance on the held-out test data, achieving a consistent mean Dice similarity coefficient (DSC) of 0.964$\pm$0.006 and an average symmetric surface distance (ASSD) of 1.4mm$\pm$0.2mm. Performance on the external dataset is comparable, with a DSC of 0.958$\pm$0.006 and an ASSD of 1.7$\pm$0.2mm. Our method achieves performance comparable to or better than existing state-of-the-art methods for brain extraction, particularly in its highly consistent preservation of the brain’s outer surface. The method is publicly available on GitHub.
[1190] ResSR: A Computationally Efficient Residual Approach to Super-Resolving Multispectral Images
Haley Duba-Sullivan, Emma J. Reid, Sophie Voisin, Charles A. Bouman, Gregery T. Buzzard
Main category: eess.IV
TL;DR: ResSR is a computationally efficient multispectral image super-resolution method that uses spectral decomposition and spatial residual correction for faster upsampling of low-resolution spectral bands.
Details
Motivation: Multispectral imaging sensors have wavelength-dependent resolution limitations, and existing MSI-SR methods are computationally expensive due to spatially regularized deconvolution and training-based approaches.Method: ResSR uses singular value decomposition for spectral correlation identification, pixel-wise computation for upsampling, and residual correction for high-spatial frequency components. It employs pixel-wise regularization and derives an approximate non-iterative solution from a spatially-coupled optimization problem.
Result: ResSR is 2× to 10× faster than alternative MSI-SR algorithms while producing comparable or better image quality on both simulated and measured data.
Conclusion: ResSR provides an efficient, non-iterative solution for multispectral image super-resolution that balances computational speed with reconstruction quality.
Abstract: Multispectral imaging sensors typically have wavelength-dependent resolution, which limits downstream processing. Consequently, researchers have proposed multispectral image super-resolution (MSI-SR) methods which upsample low-resolution bands to achieve a common resolution across all wavelengths. However, existing MSI-SR methods are computationally expensive because they require spatially regularized deconvolution and/or training-based methods. In this paper, we introduce ResSR, a computationally efficient MSI-SR method that achieves high-quality reconstructions by using spectral decomposition along with spatial residual correction. ResSR applies singular value decomposition to identify correlations across spectral bands, uses pixel-wise computation to upsample the MSI, and then applies a residual correction process to correct the high-spatial frequency components of the upsampled bands. While ResSR is formulated as the solution to a spatially-coupled optimization problem, we use pixel-wise regularization and derive an approximate non-iterative solution, resulting in a computationally efficient, non-iterative algorithm. Results on a combination of simulated and measured data show that ResSR is 2$\times$ to 10$\times$ faster than alternative MSI-SR algorithms, while producing comparable or better image quality. Code is available at https://github.com/hdsullivan/ResSR.
[1191] Clinical utility of foundation models in musculoskeletal MRI for biomarker fidelity and predictive outcomes
Gabrielle Hoyer, Michelle W Tong, Rupsa Bhattacharjee, Valentina Pedoia, Sharmila Majumdar
Main category: eess.IV
TL;DR: A modular system converts routine MRI into quantitative biomarkers using fine-tuned foundation segmenters (SAM variants) for musculoskeletal imaging, enabling automated clinical decision support applications including knee triage and osteoarthritis prediction.
Details
Motivation: Precision medicine in musculoskeletal imaging requires scalable measurement infrastructure to convert routine MRI into standardized quantitative biomarkers for clinical decision support.Method: Fine-tuned promptable foundation segmenters (SAM, SAM2, MedSAM) across heterogeneous musculoskeletal datasets, coupled with automated detection for fully automatic prompting, creating a modular, model-agnostic open-source architecture.
Result: Fine-tuned segmentations yielded clinically reliable measurements with high concordance to expert annotations across cartilage, bone, and soft tissue biomarkers. Demonstrated applications: three-stage knee triage cascade reducing verification workload while maintaining sensitivity, and 48-month landmark models forecasting knee replacement and incident osteoarthritis with favorable calibration.
Conclusion: Validates a pathway from automated measurement to clinical decision: reliable biomarkers drive both workload optimization today and patient risk stratification tomorrow, showing how foundation models can be operationalized within precision medicine systems.
Abstract: Precision medicine in musculoskeletal imaging requires scalable measurement infrastructure. We developed a modular system that converts routine MRI into standardized quantitative biomarkers suitable for clinical decision support. Promptable foundation segmenters (SAM, SAM2, MedSAM) were fine-tuned across heterogeneous musculoskeletal datasets and coupled to automated detection for fully automatic prompting. Fine-tuned segmentations yielded clinically reliable measurements with high concordance to expert annotations across cartilage, bone, and soft tissue biomarkers. Using the same measurements, we demonstrate two applications: (i) a three-stage knee triage cascade that reduces verification workload while maintaining sensitivity, and (ii) 48-month landmark models that forecast knee replacement and incident osteoarthritis with favorable calibration and net benefit across clinically relevant thresholds. Our model-agnostic, open-source architecture enables independent validation and development. This work validates a pathway from automated measurement to clinical decision: reliable biomarkers drive both workload optimization today and patient risk stratification tomorrow, and the developed framework shows how foundation models can be operationalized within precision medicine systems.
[1192] Towards Effective and Efficient Context-aware Nucleus Detection in Histopathology Whole Slide Images
Zhongyi Shui, Honglin Li, Yunlong Zhang, Yuxuan Sun, Yiwen Ye, Pingyi Chen, Ruizhe Guo, Lei Cui, Chenglu Zhu, Lin Yang
Main category: eess.IV
TL;DR: A context-aware nucleus detection method for histopathology whole slide images that aggregates contextual clues from historically visited sliding windows instead of using large field-of-view patches, improving both efficiency and accuracy.
Details
Motivation: Current nucleus detection methods process each sliding window independently, missing broader contextual information, while recent approaches using large field-of-view patches significantly increase inference latency. There's a need for both effective context integration and computational efficiency.Method: Proposes aggregating contextual clues from off-the-shelf features of historically visited sliding windows rather than using large field-of-view patches. Uses annotated patches with surrounding unlabeled patches for training, and includes a post-training strategy leveraging abundant unlabeled nucleus samples to enhance context adaptability.
Result: Extensive experiments on three challenging benchmarks demonstrate the superiority of the method, achieving both improved efficiency (reduced inference latency) and enhanced classification accuracy compared to previous approaches.
Conclusion: The proposed context-aware nucleus detection approach effectively balances computational efficiency and detection accuracy by intelligently leveraging historical window features and unlabeled data, making it suitable for practical whole-slide image analysis.
Abstract: Nucleus detection in histopathology whole slide images (WSIs) is crucial for a broad spectrum of clinical applications. The gigapixel size of WSIs necessitates the use of sliding window methodology for nucleus detection. However, mainstream methods process each sliding window independently, which overlooks broader contextual information and easily leads to inaccurate predictions. To address this limitation, recent studies additionally crop a large Filed-of-View (LFoV) patch centered on each sliding window to extract contextual features. However, such methods substantially increase whole-slide inference latency. In this work, we propose an effective and efficient context-aware nucleus detection approach. Specifically, instead of using LFoV patches, we aggregate contextual clues from off-the-shelf features of historically visited sliding windows, which greatly enhances the inference efficiency. Moreover, compared to LFoV patches used in previous works, the sliding window patches have higher magnification and provide finer-grained tissue details, thereby enhancing the classification accuracy. To develop the proposed context-aware model, we utilize annotated patches along with their surrounding unlabeled patches for training. Beyond exploiting high-level tissue context from these surrounding regions, we design a post-training strategy that leverages abundant unlabeled nucleus samples within them to enhance the model’s context adaptability. Extensive experimental results on three challenging benchmarks demonstrate the superiority of our method.
[1193] Vision Transformer for Intracranial Hemorrhage Classification in CT Scans Using an Entropy-Aware Fuzzy Integral Strategy for Adaptive Scan-Level Decision Fusion
Mehdi Hosseini Chagahi, Md. Jalil Piran, Niloufar Delfan, Behzad Moshiri, Jaber Hatam Parikhan
Main category: eess.IV
TL;DR: A PVT-based model with SHAP feature selection and entropy-aware fuzzy integral fusion for automated intracranial hemorrhage subtype classification from brain CT scans.
Details
Motivation: Intracranial hemorrhage (ICH) is a critical medical emergency requiring accurate and timely classification of subtypes for effective clinical decision-making. Current methods need improvement in capturing both local and global spatial dependencies while reducing computational complexity.Method: Uses pyramid vision transformer (PVT) with hierarchical attention mechanisms to capture spatial dependencies in CT scans. Employs SHAP-based feature selection to identify discriminative components, trains a boosting neural network on latent features, and introduces entropy-aware aggregation with fuzzy integral operator to fuse information across multiple CT slices.
Result: The PVT-based framework significantly outperforms state-of-the-art deep learning architectures in classification accuracy, precision, and robustness for ICH subtype classification.
Conclusion: The method offers a scalable and computationally efficient AI-driven solution for automated ICH subtype classification by combining SHAP-driven feature selection, transformer-based modeling, and entropy-aware fuzzy integral operator for decision fusion.
Abstract: Intracranial hemorrhage (ICH) is a critical medical emergency caused by the rupture of cerebral blood vessels, leading to internal bleeding within the skull. Accurate and timely classification of hemorrhage subtypes is essential for effective clinical decision-making. To address this challenge, we propose an advanced pyramid vision transformer (PVT)-based model, leveraging its hierarchical attention mechanisms to capture both local and global spatial dependencies in brain CT scans. Instead of processing all extracted features indiscriminately, A SHAP-based feature selection method is employed to identify the most discriminative components, which are then used as a latent feature space to train a boosting neural network, reducing computational complexity. We introduce an entropy-aware aggregation strategy along with a fuzzy integral operator to fuse information across multiple CT slices, ensuring a more comprehensive and reliable scan-level diagnosis by accounting for inter-slice dependencies. Experimental results show that our PVT-based framework significantly outperforms state-of-the-art deep learning architectures in terms of classification accuracy, precision, and robustness. By combining SHAP-driven feature selection, transformer-based modeling, and an entropy-aware fuzzy integral operator for decision fusion, our method offers a scalable and computationally efficient AI-driven solution for automated ICH subtype classification.
[1194] Sequential Attention-based Sampling for Histopathological Analysis
Tarun G, Naman Malpani, Gugan Thoppe, Sridharan Devarajan
Main category: eess.IV
TL;DR: SASHA is a deep reinforcement learning approach for efficient histopathological image analysis that uses sequential attention-based sampling to intelligently zoom into only 10-20% of high-resolution patches in gigapixel whole-slide images.
Details
Motivation: Whole-slide histopathology images are gigapixel-sized and computationally infeasible to analyze entirely at high resolution. Diagnostic labels are only available at slide-level, and diagnostic regions occupy only small fractions of the image, making full-resolution examination inefficient.Method: Two-stage approach: 1) Learns informative features with lightweight hierarchical attention-based multiple instance learning (MIL), 2) Uses deep reinforcement learning for intelligent sampling to selectively zoom into only 10-20% of high-resolution patches for diagnosis.
Result: SASHA matches state-of-the-art methods that analyze entire WSIs at high resolution while using only a fraction of computational and memory costs. It significantly outperforms competing sparse sampling methods.
Conclusion: SASHA is an intelligent sampling model for medical imaging challenges involving automated diagnosis with exceptionally large images containing sparsely informative features.
Abstract: Deep neural networks are increasingly applied in automated histopathology. Yet, whole-slide images (WSIs) are often acquired at gigapixel sizes, rendering them computationally infeasible to analyze entirely at high resolution. Diagnostic labels are largely available only at the slide-level, because expert annotation of images at a finer (patch) level is both laborious and expensive. Moreover, regions with diagnostic information typically occupy only a small fraction of the WSI, making it inefficient to examine the entire slide at full resolution. Here, we propose SASHA – Sequential Attention-based Sampling for Histopathological Analysis – a deep reinforcement learning approach for efficient analysis of histopathological images. First, SASHA learns informative features with a lightweight hierarchical, attention-based multiple instance learning (MIL) model. Second, SASHA samples intelligently and zooms selectively into a small fraction (10-20%) of high-resolution patches to achieve reliable diagnoses. We show that SASHA matches state-of-the-art methods that analyze the WSI fully at high resolution, albeit at a fraction of their computational and memory costs. In addition, it significantly outperforms competing, sparse sampling methods. We propose SASHA as an intelligent sampling model for medical imaging challenges that involve automated diagnosis with exceptionally large images containing sparsely informative features. Model implementation is available at: https://github.com/coglabiisc/SASHA.
[1195] A Survey on Medical Image Compression: From Traditional to Learning-Based Approaches
Guofeng Tong, Sixuan Liu, Yang Lv, Hanyu Pei, Feng-Lei Fan
Main category: eess.IV
TL;DR: A comprehensive survey on medical image compression that categorizes approaches by data structure (2D vs 3D/4D) and technical methods (traditional vs learning-based), analyzing challenges and future directions.
Details
Motivation: The exponential growth of medical imaging creates challenges in data storage, transmission, and management, requiring efficient compression that preserves diagnostic details and structural integrity while balancing computational complexity with clinically acceptable quality.Method: Establishes a two-facet taxonomy: (1) data structure (2D images vs 3D/4D volumetric/dynamic imaging) and (2) technical approaches (traditional mathematical transform-based methods vs deep learning-based approaches).
Result: Systematically presents the complete technological evolution of medical image compression, analyzes unique technical challenges for different modalities, and prospects future directions in the field.
Conclusion: Medical image compression requires specialized approaches that differ from natural image compression, with traditional methods providing theoretical foundations and standardization while deep learning offers adaptive learning capabilities; the survey provides a comprehensive framework for understanding this evolving field.
Abstract: The exponential growth of medical imaging has created significant challenges in data storage, transmission, and management for healthcare systems. In this vein, efficient compression becomes increasingly important. Unlike natural image compression, medical image compression prioritizes preserving diagnostic details and structural integrity, imposing stricter quality requirements and demanding fast, memory-efficient algorithms that balance computational complexity with clinically acceptable reconstruction quality. Meanwhile, the medical imaging family includes a plethora of modalities, each possessing different requirements. For example, 2D medical image (e.g., X-rays, histopathological images) compression focuses on exploiting intra-slice spatial redundancy, while volumetric medical image faces require handling intra-slice and inter-slice spatial correlations, and 4D dynamic imaging (e.g., time-series CT/MRI, 4D ultrasound) additionally demands processing temporal correlations between consecutive time frames. Traditional compression methods, grounded in mathematical transforms and information theory principles, provide solid theoretical foundations, predictable performance, and high standardization levels, with extensive validation in clinical environments. In contrast, deep learning-based approaches demonstrate remarkable adaptive learning capabilities and can capture complex statistical characteristics and semantic information within medical images. This comprehensive survey establishes a two-facet taxonomy based on data structure (2D vs 3D/4D) and technical approaches (traditional vs learning-based), thereby systematically presenting the complete technological evolution, analyzing the unique technical challenges, and prospecting future directions in medical image compression.
[1196] Predicting brain tumour enhancement from non-contrast MR imaging with artificial intelligence
James K Ruffle, Samia Mohinta, Guilherme Pombo, Asthik Biswas, Alan Campbell, Indran Davagnanam, David Doig, Ahmed Hammam, Harpreet Hyare, Farrah Jabeen, Emma Lim, Dermot Mallon, Stephanie Owen, Sophie Wilkinson, Sebastian Brandner, Parashkev Nachev
Main category: eess.IV
TL;DR: Deep learning models can predict brain tumor contrast enhancement from non-contrast MRI sequences alone, potentially reducing gadolinium dependence in neuro-oncology imaging.
Details
Motivation: Gadolinium administration for contrast-enhanced MRI is not always desirable due to frequent follow-up needs, renal impairment, allergies, or pediatric patients. There's a need to develop methods that can predict contrast enhancement from non-contrast sequences alone.Method: Used 11,089 brain MRI studies from 10 international datasets spanning adult and pediatric populations with various neuro-oncological conditions. Trained deep learning models (nnU-Net, SegResNet, SwinUNETR) to predict and segment enhancing tumor using only non-contrast T1-, T2-, and T2/FLAIR-weighted images.
Result: Best-performing nnU-Net achieved 83% balanced accuracy, 91.5% sensitivity, and 74.4% specificity in detecting enhancing tumor. Enhancement volume predictions strongly correlated with ground truth (R² 0.859). Model outperformed expert radiologists (69.8% accuracy, 75.9% sensitivity, 64.7% specificity). 76.8% of test patients had Dice >0.3, 67.5% >0.5, and 50.2% >0.7.
Conclusion: Deep learning can identify contrast-enhancing brain tumors from non-contrast MRI with clinically relevant performance. These models show promise as screening tools and may reduce gadolinium dependence in neuro-oncology imaging.
Abstract: Brain tumour imaging assessment typically requires both pre- and post-contrast MRI, but gadolinium administration is not always desirable, such as in frequent follow-up, renal impairment, allergy, or paediatric patients. We aimed to develop and validate a deep learning model capable of predicting brain tumour contrast enhancement from non-contrast MRI sequences alone. We assembled 11089 brain MRI studies from 10 international datasets spanning adult and paediatric populations with various neuro-oncological states, including glioma, meningioma, metastases, and post-resection appearances. Deep learning models (nnU-Net, SegResNet, SwinUNETR) were trained to predict and segment enhancing tumour using only non-contrast T1-, T2-, and T2/FLAIR-weighted images. Performance was evaluated on 1109 held-out test patients using patient-level detection metrics and voxel-level segmentation accuracy. Model predictions were compared against 11 expert radiologists who each reviewed 100 randomly selected patients. The best-performing nnU-Net achieved 83% balanced accuracy, 91.5% sensitivity, and 74.4% specificity in detecting enhancing tumour. Enhancement volume predictions strongly correlated with ground truth (R2 0.859). The model outperformed expert radiologists, who achieved 69.8% accuracy, 75.9% sensitivity, and 64.7% specificity. 76.8% of test patients had Dice over 0.3 (acceptable detection), 67.5% had Dice over 0.5 (good detection), and 50.2% had Dice over 0.7 (excellent detection). Deep learning can identify contrast-enhancing brain tumours from non-contrast MRI with clinically relevant performance. These models show promise as screening tools and may reduce gadolinium dependence in neuro-oncology imaging. Future work should evaluate clinical utility alongside radiology experts.
[1197] W-DUALMINE: Reliability-Weighted Dual-Expert Fusion With Residual Correlation Preservation for Medical Image Fusion
Md. Jahidul Islam
Main category: eess.IV
TL;DR: W-DUALMINE is a reliability-weighted dual-expert fusion framework for medical image fusion that resolves the trade-off between global statistical similarity and local structural fidelity through architectural constraints and theoretically grounded loss design.
Details
Motivation: Existing deep learning-based medical image fusion methods, including spatial-frequency frameworks like AdaFuse and ASFE-Fusion, suffer from a fundamental trade-off between global statistical similarity (measured by correlation coefficient and mutual information) and local structural fidelity.Method: Proposes W-DUALMINE with dense reliability maps for adaptive modality weighting, dual-expert fusion combining global-context spatial expert and wavelet-domain frequency expert, soft gradient-based arbitration mechanism, and residual-to-average fusion paradigm.
Result: Extensive experiments on CT-MRI, PET-MRI, and SPECT-MRI datasets demonstrate that W-DUALMINE consistently outperforms AdaFuse and ASFE-Fusion in CC and MI metrics.
Conclusion: W-DUALMINE effectively resolves the trade-off between global statistical similarity and local structural fidelity in medical image fusion through its architectural design and loss formulation.
Abstract: Medical image fusion integrates complementary information from multiple imaging modalities to improve clinical interpretation. However, existing deep learningbased methods, including recent spatial-frequency frameworks such as AdaFuse and ASFE-Fusion, often suffer from a fundamental trade-off between global statistical similaritymeasured by correlation coefficient (CC) and mutual information (MI)and local structural fidelity. This paper proposes W-DUALMINE, a reliability-weighted dual-expert fusion framework designed to explicitly resolve this trade-off through architectural constraints and a theoretically grounded loss design. The proposed method introduces dense reliability maps for adaptive modality weighting, a dual-expert fusion strategy combining a global-context spatial expert and a wavelet-domain frequency expert, and a soft gradient-based arbitration mechanism. Furthermore, we employ a residual-to-average fusion paradigm that guarantees the preservation of global correlation while enhancing local details. Extensive experiments on CT-MRI, PET-MRI, and SPECT-MRI datasets demonstrate that W-DUALMINE consistently outperforms AdaFuse and ASFE-Fusion in CC and MI metrics while