Artificial Intelligence
Copies or Sources? Measuring How LLM Aggregators Count Restated Evidence in Multi-Agent Systems
Jianxin Gao, Runze Li, Tianyi Yu et al. (+3 more)
Multi-
agent systems built on large
language models (LLMs) restate observations as a matter of course: relays forward them, shared boards repeat them and discussion rounds echo them. An aggregator that pools such messages should count sources, not statements. We convert a reported probability into units of independent readings, which assigns every restatement a copy weight, 0 for an aggregator that counts sources and 1 for one that counts every statement, and yields the implied decision under any cost structure. Three testbeds hold the evidence fixed and vary how it is restated: message logs with an exact
Bayesian oracle, web documents with appended copies, and logs written by LLM
agent teams under four communication protocols. Across four models from three providers, a forwarded copy counts for 0.06 to 0.42 of a new reading, mostly because some replies count every statement. On 5% to 40% of logs that state one reading three times, the reported belief implies an early commitment that the oracle never makes. The models that count copies least and most on controlled logs do so on web copies and
agent-written logs as well. A one-paragraph declaration of what a copy contributes brings the copy weight on controlled logs to 0.08 or less. A rule that has
agents refer to readings instead of restating them cuts belief-implied early commitment from 11.2% to 1.1% and preserves genuine corroboration.
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All authors Jianxin Gao, Runze Li, Tianyi Yu, Liangwei Ren, Bohan Chen, Zining Wang
Artificial Intelligence
Judged Useless, Queried Anyway: Tool-Using Agents Rarely Turn Their Own Evidence Judgments into Stopping Decisions
Chubin Zhang, Zhenglin Wan, Xingrui Yu et al. (+4 more)
An
agent whose tool keeps returning nothing useful should stop relying on it. In a
retrieval environment with controlled source failures, we separate how
agents judge results from what they do. We compare stopping at the same step after longer and shorter runs of results the
agent judged useless; this contrast is zero for clock- or deadline-driven stopping. Where we record their judgments, the seven
agents we test call a failing source's results useless 97-100% of the time, yet most of them rarely stop on that judgment.
Prompt cues change when they stop but not what they stop on. Permission to answer from
memory and a
reasoning mode can bring early stops regardless of evidence, a stated budget moves the 7-8B models' stops to the deadline, and a stopping rule or call cost in the
prompt is followed at most partly. Stopping follows the evidence only when the harness enforces an integration step that makes the
agent answer after five consecutive results it judged useless. This step raises failing-source success for every model, keeps the stopping point fixed when the budget doubles, and needs no extra judgment call when the
agent states its judgments. A pre-registered replication on 300 fresh questions confirms the dissociation and the rule's effect.
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All authors Chubin Zhang, Zhenglin Wan, Xingrui Yu, Jingxuan Wu, Yaxin Zhou, Ivor Tsang, Bo An
Artificial Intelligence
Bridging the Evidence-to-Execution Gap:A Reflective Agent for Multi-Objective Peptide Design
Haosen Zhang and Yang Yang
Large
language models (LLMs) can reason over scientific literature to devise design strategies, yet fail to reliably implement them for biological sequences. While
protein generative models learn sequence patterns, they lack the capacity to incorporate literature evidence for multi-step reflective
reasoning, forming an evidence-to-execution gap between scientific
reasoning and sequence manipulation. We present EASER (Evidence-Aware Sequence Engineering with Reflection), a reflective
agent bridging
reasoning and sequence generation via a learned property interface of offline-trained, fixed low-rank
matrices. The
agent steers a
diffusion generator by combining these
matrices, proposing intervention hypotheses (anchors, editable positions, control coefficients) grounded in retrieved evidence, sequence context and past results. A Probe-and-Steer mechanism validates interventions and allocates samples according to predicted property responses, with outcome reflection informing subsequent decisions. Evaluated on multi-objective antimicrobial peptide design (optimizing activity, non-hemolysis and non-toxicity), explicit hypothesis formulation delivers better multi-objective performance than direct action generation under identical decision conditions. Ablation studies verify the importance of evidence
retrieval, episodic history, reflection and Probe-and-Steer. Over six repeated trials, EASER obtains the highest mean hypervolume and lowest mean IGD+ on screened candidates compared with competing baselines. Our work demonstrates how an executable property interface and iterative feedback link scientific
reasoning to targeted peptide sequence generation.
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Artificial Intelligence · Cross-listed from cs.LG
Anlu: Enabling In-Context Time Series Anomaly Detection in Foundation Models via Counterfactual Supervision
Tian Lan, Yifei Gao, Yimeng Lu et al. (+5 more)
Whether a time-series pattern is anomalous often depends on the operating regime of the monitored process. A missing event can signal a fault in one regime and be routine in another, and the query alone may not reveal which regime applies. We study in-context learning (ICL) for time series anomaly detection (TSAD) through reference-conditioned detection, where a reference record provides evidence about expected behavior and model parameters remain fixed at inference. Supplying the reference is not enough: when training anomalies are recognizable from the query alone, the detector can fit its targets while ignoring the reference. We therefore introduce counterfactual supervision, which pairs one query with two references that support different normal rules and labels the query under each. At positions where the two labels disagree, no detector that ignores the reference can fit both targets. Anlu learns from this supervision by adding a reference
memory and zero-initialized gated adapters to a frozen time-series foundation model (TSFM) pretrained for anomaly detection. On the 350 TSB-AD-U evaluation sequences, Anlu raises the mean VUS-PR of the frozen TSFM from 0.542 to 0.607. Replacing the reference with zeros lowers Anlu's score to 0.499.
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All authors Tian Lan, Yifei Gao, Yimeng Lu, Xuming An, Meng Wang, Yue Pan, Wenjun He, Chen Zhang
Artificial Intelligence
Auditable Clinical Timeline Reconstruction with Provenance-Aware Evidence Graphs
Judith Jeyafreeda Andrew
A patient-timeline reconstruction system is auditable only if it keeps the mentions behind each answer, records how facts were revised, and declines to answer when the evidence is not in the text. This study tests these three properties on a fully synthetic corpus (1,000 patients, 3,353 notes, 220 revision edges). Two provenance-aware Evidence Graph operators reduced the node-plus-edge count to 67% and 63% (77-78% of serialized size) while preserving every answer and mention link across 6,813 query points answerable by recency; a fixed-window baseline returned no value for 53.4% of points, unflagged. On evidence-unavailable controls that announce the omission, a BioClinicalBERT gate and a zero-shot LLM gate responded mainly to the announcement. On marker-free controls, BERT abstained on 0 of 81 notes while its accuracy fell from 93.8% to 59.3% across all three relation classes; the LLM's coverage fell from 75.6% to 27.7% on notes its own model family judged undeterminable. Against 482 regenerated gold spans, the LLM's cited evidence reached recall 0.850 and precision 0.864; BERT's span head, trained without span labels, did not localize evidence. A temporally versioned provenance graph stored abstentions as typed, queryable edges. The clean task admits a 0.651-accuracy shortcut, and results describe implementation behaviour on synthetic data, not clinical performance.
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Artificial Intelligence · Cross-listed from cs.LG
Anosognosia in LLMs: Probing Self-Awareness of Quantized Computational Substrate
Yoshihiro Izawa, Gouki Minegishi and Yoko Yamakata
Can LLMs recognize degradation in their own computational substrate? Inspired by anosognosia, a neurological condition in which patients fail to recognize impairments in their own abilities, we investigate whether LLMs can recognize degradation in their computational substrate induced by quantization. We first show that existing models fail to self-report their quantization state, even when provided with their own generated text as an external cue. Linear probing reveals that, while generated text carries almost no trace of quantization, internal representations contain clear, method-specific fingerprints. Through training, models learn to identify severely degraded outputs such as those of 4-bit models by comparison, yet still fail to do so from a single output. A shared LoRA trained jointly across quantization levels succeeded in reading out internal fingerprints, but fails on unseen quantization methods, merely mapping method-specific fingerprints to labels. Whereas external self-observation can restore awareness in some cases of human anosognosia, our results suggest that the more promising route to enabling such awareness in LLMs may lie in their internal representations. Our results highlight fundamental limits of generalizability to LLM self-monitoring.
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Artificial Intelligence
MS-Exam-Gen: An Automatic Benchmark Construction Toolkit for Evaluating LLMs on Multiple Sclerosis-MRI Imaging Knowledge
Abdul Basit, Muhammad Abdullah Hanif and Muhammad Shafique
Biomedical large
language model (LLM) evaluation requires auditable assessment of narrow, evolving, source-grounded subspecialty knowledge. Multiple sclerosis MRI (MS-MRI) provides a high-stakes textual-knowledge test case because correct
reasoning requires current diagnostic criteria, standardized acquisition and reporting knowledge, longitudinal monitoring concepts, lesion morphology, and recognition of difficult mimics. We present MS-Exam-Gen, a reproducible framework for constructing and auditing a text-based multiple-choice question (MCQ)
benchmark for MS-MRI knowledge; it does not evaluate direct MRI image interpretation. MS-Exam-Gen targets source-grounded criteria, protocols, reporting, and differential diagnosis. The framework combines expert-source indexing, exam-oriented topic induction, evidence-grounded MCQ generation, automated quality audits, a same-family consistency screen, and empirical calibration. From a 66-source corpus indexed into 4,289
retrieval chunks, the pipeline produced a locked 3,058-item candidate
benchmark spanning 16 topics and 53 subtopics. Evaluation across 12 primary LLM endpoints yielded 36,696 item-level predictions and separated performance over a 42.8-percentage-point accuracy range (89.7% to 46.9%). Across these endpoints, 25.5% of items were missed by at least four. Post-generation audits showed that refreshed construction reduced measurable answer cues, while option-order testing showed that absolute MCQ scores remain position-sensitive. Generated construction labels remain metadata rather than validated psychometric categories. Because expert adjudication and full option-order counterbalancing remain future work, MS-Exam-Gen is not a clinically certified examination. It should be interpreted as an automatically filtered, source-grounded candidate
benchmark and reproducible audit workflow for item-level and topic-specific LLM evaluation.
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Artificial Intelligence · Cross-listed from cs.CR
Where Did the Repair First Go Wrong? Localizing the Origins of Silent Failures in Agentic Vulnerability Repair
Wenji Bai, Muhammad Waseem, Zeeshan Rasheed et al. (+2 more)
Localizing where an LLM-based
agent first fails to uphold security during a repair can show which stage of its workflow needs an additional safeguard. This is difficult for silent failures, which are patches that pass syntactic and functional checks but still contain a security vulnerability. Because such patches give no observable failure signal, existing failure attribution methods, which rely on observed task failures and labelled failure steps, are less suited to them. We propose Security Awareness Gap Evaluation (SAGE), a trace-based method that combines an assessment of the security
reasoning recorded at each turn with the reconstructed code history to identify the earliest turn at which a repair diverges from the task's security intent. We evaluate SAGE on 95 confirmed silent failures drawn from 3,684 repair traces produced by six
agent frameworks and six base models on SecurityEval and CVEfixes. SAGE assigned an origin in 93 cases. Most origins were an unaddressed security requirement or an inadequate defence choice, and only five coincided with the code change itself. When the
agent introduced the vulnerable code, the origin preceded the write in 14 of 19 cases. Repeated scoring and a second judge reproduced the origin type more consistently than the exact turn, and agreement was lowest for traces that kept only the final file.
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All authors Wenji Bai, Muhammad Waseem, Zeeshan Rasheed, Jaakko Peltonen, Pekka Abrahamsson
Artificial Intelligence
Impact of Data Augmentation on Confidence Calibration in Melanoma Classification
Morgan May, Simon Caton and Pierpaolo Dondio
Accurately quantifying the predictive uncertainty or improving model calibration plays an important role in medical image classification, in particular in melanoma diagnosis, where accurate uncertainty quantification can have significant implications for patient care. One of the methods for calibration improvement is data augmentation. In addition, data augmentation as a method for synthetically increasing the size of the
dataset has been proven to improve the performance of models trained on imbalanced
datasets. However, the impact of data augmentation, as a transformation of a part of the original data, on calibration of models trained on imbalanced
datasets, in particular in melanoma classification is under-explored. We train neural networks on SIIM-ISIC 2020 melanoma classification
dataset under two conditions: with and without data augmentation, and compare the differences in AUC and expected calibration error (ECE) in both scenarios. Our results shows improvements in uncertainty calibration using different augmentation methods.
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Artificial Intelligence
On Impact of Loss Function on the Performance of Neural Networks in Melanoma Diagnosis
Morgan May, Pierpaolo Dondio and Simon Caton
Melanoma is the deadliest type of skin cancer, whose early diagnosis is crucial for patients' survival. Image classification using deep learning models has shown promising results for melanoma diagnosis. However, the performance of these models on the melanoma
datasets such as SIIM-ISIC melanoma classification
dataset is a challenge due to the class imbalance. One of the methods to deal with this challenge is using loss function modifications. In this work, we have investigated the effect of different loss functions on the performance of deep neural networks. We trained these networks using focal loss, logit-adjusted softmax cross-
entropy (CE) loss, and weighted softmax CE loss, and we report different metrics for evaluating performance and uncertainty calibration. Our results suggest that focal loss delivers a good combination of performance in terms of AUC and uncertainty calibration in terms of expected calibration error (ECE) simultaneously.
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Artificial Intelligence · Cross-listed from cs.LG
Machine learning for journal entry testing: A type-aware evaluation of anomaly detectors under a review budget
Jan Gronewald, Michel Scherer and Nijat Mehdiyev
Journal entry anomaly detectors are commonly evaluated on the full population with ROC-AUC, precision and recall, ignoring the review budget and which anomaly types are found. We propose a type-aware evaluation combining per-type recall, fair-share type recall (FSR), which caps each type's credit at its budget share, type coverage and first-hit rank. We evaluate nine unsupervised detectors, a supervised reference and feedback-driven Deep Semi-Supervised Anomaly Detection (DeepSAD) on four real client ledgers with injected typed anomalies and a public synthetic ledger. On the largest client ledger, principal component analysis (PCA), an autoencoder (AE) and a variational autoencoder (VAE) each place on average 98 anomalies among the first 100 postings, but at least 95.8 belong to one type. FSR instead favours a nearest-neighbour (kNN) detector and changes the top-ranked detector on three of four client ledgers. Representation also matters: one-hot encoding exposes unseen accounts, whereas frequency encoding leaves unseen contra accounts largely undetected. On the public ledger, the Histogram-Based Outlier Score (HBOS) and Empirical Cumulative Distribution-Based Outlier Detection (ECOD) reach all eight markings within 1,386 entries, whereas kNN, the hit leader at 1,000 entries, first reaches cross-linked clearing at rank 4,641, and the supervised row-level reference misses this marking within 1,000 entries. There, the adaptive DeepSAD review protocol raises mean hits per 100 reviews from 40.0 to 68.3 but type coverage only from 2.7 to 3.0. These findings show that high hit rates can conceal systematic blind spots and suggest that feedback can reinforce existing detection patterns without broadening anomaly coverage.
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Artificial Intelligence
Benchmarking Jailbreak Guardrails for Embodied Agents
Xunguang Wang, Qingyue Wang, Yuguang Zhou et al. (+3 more)
Embodied
agents powered by large
language models and
vision-
language models are increasingly deployed in physical environments, but jailbreak attacks can induce these
agents to perform physically harmful actions. A growing number of guardrail methods have been proposed to intercept dangerous behavior before it is executed, yet existing safety
benchmarks evaluate the embodied models themselves, leaving it unclear how well these guardrails actually defend an embodied
agent in practice. We present the first systematic evaluation of jailbreak guardrails for embodied
agents. To compare guardrails under identical conditions, we build a pluggable evaluation framework that treats the embodied
agent as a fixed backend and each guardrail as a module that can intervene at the perception, planning, or control stage. We subject six representative guardrails to template-based and automated jailbreak attacks as well as safe instructions, and assess them at the system level along three dimensions: defense effectiveness, measured by the bypass rate and the hazard success rate in the simulator; usability, measured by the false-positive rate and the task completion rate on safe instructions; and efficiency, measured by the latency overhead added at runtime. Experiments on guardrails that span different intervention stages, decision mechanisms, and input modalities reveal a clear trade-off among the three dimensions, and show that no single guardrail dominates in all settings. We further analyze how intervention stage, decision mechanism, and input modality shape safety outcomes, and we offer practical guidance for selecting and designing guardrails for embodied
agents.
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All authors Xunguang Wang, Qingyue Wang, Yuguang Zhou, Zongjie Li, Wenxuan Wang, Shuai Wang
Artificial Intelligence · Cross-listed from cs.LG
On the Geometry of Multimodal Saturation: Riemannian VICReg
Nessim Ben Abbes, Duc Han Le, Sabri Mtibaa et al. (+1 more)
In self-supervised learning, a third modality should improve, or at least preserve, performance. Across nine image-text-tabular
datasets, we show that it instead harms performance: the trimodal model underperforms its own best bimodal subset in 55.6% of paired runs under VICReg. The same failure occurs in 51.1% of paired runs under SimSiam. We call this failure
multimodal saturation. We propose that the failure lies in the
alignment geometry. Riemannian VICReg (R-VICReg) generalizes classical VICReg: it aligns views by squared geodesic distance on learnable negative-
curvature product factors and recovers VICReg exactly as
curvature vanishes. Over the same 45 paired runs, R-VICReg raises the probability that the third modality helps from 44.4% to 64.4%, with gains concentrated where VICReg saturates.
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All authors Nessim Ben Abbes, Duc Han Le, Sabri Mtibaa, Van-Tam Nguyen
Artificial Intelligence · Cross-listed from cs.CL
Cross-Lingual Transferability of Training Data Extraction Attacks to Recover Memorized PII
Alexandru Nazare, Agnese Profico, Nicolò Vania et al. (+6 more)
The robustness of Personally Identifiable Information (PII) protection in Large
Language Models (LLMs) is a critical concern, yet the risks associated with cross-lingual data extraction remain under-explored. This study evaluates the vulnerability of English-centric and multilingual models to Training Data Extraction (TDE) attacks when prompted in non-English
languages. We construct a multi-domain PII
dataset comprising social media handles, email addresses, and phone numbers and translate the attack contexts into Italian, Spanish, French, and German. Our results show that TDE attacks against both English-centric and multilingual models transfer to different
languages: the attacks are successful on translated
prompts, even though only the original English
prompt might have been included in the pre-training data. A web-presence check on a sample of the translations confirms that they are not available online. The share of English leaks recovered in other
languages grows with the multilingual capability of the model, and it drops sharply when the original wording is lost, even without a change of
language. This suggests that native multilingual pre-training facilitates the emergence of latent cross-linguistic bridges that simplify the
retrieval of personally identifiable information (PII). We analyze the activations of multilingual large
language models (LLMs) and find that different translations of the same
prompt are bridged in similar representations, with the strongest
alignment in the middle layers. Our results highlight a fundamental security gap in modern LLMs, necessitating more robust,
language-agnostic sanitization strategies for future model
alignment.
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All authors Alexandru Nazare, Agnese Profico, Nicolò Vania, Elena Di Croce, Daria Caramanica, Davide Venditti, Elena Sofia Ruzzetti, Giancarlo A. Xompero, Fabio Massimo Zanzotto
Artificial Intelligence · Cross-listed from cs.RO
Adaptive Mean Flow for Responsive Closed-Loop Robot Control
Aksel Vaaler, Marco Job, Christian Holden et al. (+1 more)
Diffusion- and flow-based
robot policies have recently become widespread in robotic Imitation Learning (IL) due to their high performance and ability to model continuous and
multimodal distributions. However, the iterative denoising procedure used by these models introduces significant prediction latency, hindering high-frequency closed-loop
robot control and leading to jittery, unstable motion when frequent updates to the
robot's action predictions are used. Therefore, it is common practice to train models to predict chunks of actions that can be executed sequentially without feedback, even when this reduces responsiveness and may mean the most recent state information is not used. In this article, we present Adaptive Mean Flow (AMF), a flow-based IL method that enables smooth and responsive, fully closed-loop
robot control. AMF uses Mean Flow, which is an accelerated form of Flow Matching (FM), to minimize prediction latency. To ensure smoothness and consistency across predictions, AMF uses a corrupted version of the trajectory from the previous step when predicting new
robot actions, with the signal-to-noise ratio increasing over the time parameter of the trajectory. This discourages large changes in the prediction from one step to the next, while allowing freedom to adapt the predictions for future steps. We evaluate AMF across a wide range of simulated and real
robot tasks and demonstrate significantly improved performance compared with baselines. Code: https://github.com/akselva/Adaptive-mean-flow-RoboticIL.
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All authors Aksel Vaaler, Marco Job, Christian Holden, Olav Egeland
Artificial Intelligence · Cross-listed from cs.LG
Boosting Transferable Adversarial Attacks against Deep Reinforcement Learning
Zexin Li, Ruili Yao, Yiming Zeng et al. (+1 more)
Most
adversarial attacks on deep reinforcement learning (DRL) assume white-box access to the victim policy, which rarely holds in practice. This paper studies transfer-based black-box attacks on DRL: the attacker crafts observation perturbations on a white-box surrogate
agent and feeds them to an unknown victim. We formulate the attack as return minimization under a per-step perturbation budget. We first show that transplanting transferable image-classification attacks (FGSM, MI-FGSM, and NI-FGSM) with a per-step objective yields perturbations that transfer but are no stronger than random noise of the same budget. We then propose a trajectory-level attack that optimizes a sequence of perturbations over a receding horizon through a differentiable model of the environment and a temperature-smoothed surrogate policy, with the same optimizers. On CartPole-v1 with ten DQN and DDQN
agents and 100 surrogate–victim pairs, the trajectory-level attack outperforms per-step attacks and random noise in the white-box, cross-model, and cross-
algorithm settings.
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All authors Zexin Li, Ruili Yao, Yiming Zeng, Xiaoxue Gao
Artificial Intelligence · Cross-listed from cs.RO
Do VLAs Understand and Adapt to the Objects They Handle, or Simply Replay Learned Behaviors?
Xinnuo Xu
This paper asks whether VLA generalization is grounded in a global understanding of objects' physical properties that enables policies to adapt their motion to unseen setups, or if policies simply replay the motions they've learnt that happen to succeed in new setups. The former reflects genuine generalization; the latter reflects incidental robustness. We first examine awareness of physical properties in seven VLAs by applying linear probing and representational similarity analysis (RSA) to their activations. We find that physical properties, including mass, fragility, deformability, friction and size are less decodable than non-physical properties such as semantic category, material, sound and price in nearly every modality stream. Compared with their base VLMs,
robot pre-training weakens the linear encoding of physical properties in the
language stream. Neither pre-training nor downstream fine-tuning strengthens the
alignment between physical-property differences and activation distances. We then ask whether the weak physical information present in these activations shapes the actions a VLA generates. In a controlled LIBERO case study, we increase the mass of an in-domain object and signal the change through
language or
vision. Most VLAs use similar lifting behaviour for the heavier and original-mass objects, leading to task success declines. The few exceptions change their behaviour in response to lexical or visual cues rather than to mass itself. These results suggest that VLAs encode physical properties weakly and do not reliably use them to adapt their motion.
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Artificial Intelligence · Cross-listed from cs.MA
Attention Tax, Handoff Tax: A Stylised Model of When Multi-Agent LLM Systems Help
Akshit Anchan and Nayonika Sen
Recent work on multi-
agent LLM systems reaches sharply different conclusions: some results show that a single
agent with the same information and compute should dominate a delegated system, others that multi-
agent gains grow with task depth. We argue that much of the disagreement comes from modelling different bottlenecks, and introduce a stylised reliability model built around two trade-offs. Decomposition reduces the burden of long contexts but incurs a handoff tax when information is compressed or transferred between
agents. Redundancy gains from multiple samples, but its benefit depends on how much their failures are shared. With
reasoning budget, verification, and task structure added, the model yields two crossover conditions: decomposition becomes preferable once the
attention cost avoided by resetting context exceeds the handoff cost, and parallel sampling at equal budget is eventually preferable when its shared-failure floor lies below the error floor of one
agent thinking longer. We connect these regimes to recent theoretical and empirical results. On a ledger-reconciliation task we measure the context-degradation curve and the handoff tax from single-
agent and handoff runs alone. From these the model places the crossover at depth 10 and predicts decomposition to win at depths 20, 50, and 100. It does, on step-level and final-balance accuracy, and the decomposed system's success, which the prediction never sees, lands within 9 percentage points of the predicted rate at every depth.
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Artificial Intelligence · Cross-listed from cs.CV
Vision Transformer Ensembles for Panoramic Street Segmentation
Yunus Serhat B{\i}çakç{\i}
Semantic segmentation of street panoramas can support detailed descriptions of urban environments, yet small
datasets and unequal training costs make model selection difficult. This paper presents the system used for a first place submission to the PalmCity challenge in the leaderboard snapshot dated 5 October 2026. Nine pretrained segmentation systems are compared using approximately equal computation budgets. The candidates include DeepLabV3+, SegFormer, UPerNet, Mask2Former, DINOv3 with a linear decoder, and an Encoder only Mask
Transformer using DINOv3. The two leading candidates are trained independently with three random seeds and longer budgets. Equal averaging of class probabilities from the three Encoder only Mask
Transformer models, evaluated at three image scales with horizontal reflection, produces 60.95% mean intersection over union and 71.16% mean F1 on the 84 image public validation split. The submitted predictions receive 57.08% mean intersection over union and 67.96% mean F1 on the hidden test leaderboard. Producing all 249 test masks takes 251.49 seconds including model initialization and provenance checks on one NVIDIA RTX 5090. Peak allocated GPU
memory is 2.70 GiB. The study reports all eligible models, all inference variants, class level errors, source conditions, and reproducibility checks, providing a documented challenge workflow with existing architectures.
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Artificial Intelligence · Cross-listed from cs.SD
A Comprehensive Objective Evaluation of Modern Text-to-Speech for Turkish Using Speech Quality Assessment Models
Yunus Emre Ozkose, Alperen Kahraman and Ali Haznedaroglu
Modern text-to-
speech (TTS) systems can clone a target speaker from a short reference clip or be fine-tuned on a target voice, yet their behaviour on morphologically rich, lower-resource
languages such as Turkish remain under-characterised. We present a systematic
benchmark of four contemporary systems (Chatterbox, CosyVoice, OmniVoice, and VoxCPM2) evaluated across fine-tuned and zero-shot configurations, contrasted with a conventional VITS baseline and anchored to natural gold
speech. Each configuration is scored with eighteen complementary objective metrics spanning learned naturalness predictors (UTMOS v2, DNSMOS-Pro, SCOREQ, WhisQA, AudioBox-PQ, NatScore, SpeechLMScore), intelligibility and signal-quality
estimators (SQUIM PESQ/SI-SDR/STOI, Brouhaha), speaker similarity, distributional fidelity (TTSDS) and low-level acoustic descriptors. We further analyse how quality varies with utterance length and quantify long-form temporal consistency through speaker-identity and naturalness drift over chunked utterances. We release our evaluation code to support reproducible TTS evaluation.
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Artificial Intelligence · Cross-listed from cs.CV
ROT: Rotating Hidden States towards Contextual Vectors for Hallucination Mitigation in LVLMs
Yijing Du, Xiangcheng Zhan and Shuo Yang
Large
Vision-
Language Models (LVLMs) frequently suffer from object
hallucination. Existing training-free interventions primarily manipulate
attention weights, which indirectly affect the deep semantics reaching the final predictive layers. In this work, we shift our focus to the hidden state vectors extracted after self-
attention and residual addition. Empirical analysis reveals that hallucinated
tokens do not simply over-rely on linguistic priors; instead, they exhibit an anomalous contextual deviation, showing significantly lower similarities to both textual and visual contexts in intermediate layers. Motivated by this, we propose ROT, a layer-specific, training-free framework. ROT dynamically detects semantic deviation in the middle layers and applies a norm-preserving rotation to steer the hidden states back toward the local
multimodal context plane spanned by the contexts. For subsequent layers, a representational smoothing mechanism is introduced to stabilize the calibrated trajectory. Extensive experiments on multiple
benchmarks demonstrate that ROT consistently reduces
hallucinations across various model architectures and scales, offering an efficient, geometry-driven solution for grounded generation.
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Artificial Intelligence · Cross-listed from cs.CV
Local2Mesh: Spatially Localized Contour-to-Mesh for Left Ventricular Reconstruction from Sparse 2D Cardiac MRI
Haoyu Wu, Ling Lin, Pascal Lefèvre et al. (+2 more)
Three-dimensional (3D) left ventricular (LV) reconstruction from sparse cardiac
magnetic resonance (CMR) imaging remains challenging due to inter-slice misalignment and insufficient local spatial information between slices. Global aggregation of contour features may obscure local contour-to-surface relationships. We propose Local2Mesh, a spatially localized contour-to-mesh framework that deforms a template mesh to reconstruct 3D LV geometry from sparse 2D contours without 3D mesh annotations. The framework introduces geometry-aware
alignment to correct inter-slice misalignment and a plane-aware Local Router that routes contour features to template vertices using vertex-to-plane distances. Local and global contour features then jointly guide graph-based template deformation for 3D LV reconstruction. Experiments on two public
datasets, M&Ms-2 and ACDC, demonstrate superior
geometric reconstruction and functional estimation over existing methods. Zero-shot transfer from M&Ms-2 to ACDC demonstrates strong cross-
dataset generalization. Reconstructed meshes also improve disease classification over sparse contours, supporting their utility for downstream cardiac analysis. These results demonstrate that combining geometry-aware
alignment with local contour-to-vertex modeling improves LV reconstruction from sparse 2D contours and supports downstream cardiac analysis. The code is available at https://github.com/hwu918945-alt/loca2mesh.
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All authors Haoyu Wu, Ling Lin, Pascal Lefèvre, Ruizhe Li, Xiaowu Sun
Artificial Intelligence · Cross-listed from cs.CR
Backdooring Sparse Autoencoders
Enrico Ahlers, Daniel Passon, Tobias Kiecker et al. (+2 more)
Sparse autoencoders (SAEs) are increasingly used not only to interpret
language models but also to intervene on their internal representations. We show that this creates a supply-chain attack surface: a maliciously modified SAE can induce attacker-chosen behavior when inserted into the forward pass of an otherwise unchanged
language model. We introduce a decoder-only SAE backdoor that leaves both the underlying LLM and the SAE encoder frozen, restricting the attack to a single auxiliary component at a single insertion layer. Using code generation as a case study, we demonstrate high rates of unsolicited code insertion across three
language models and a wide range of insertion layers, as well as trigger-dependent behavior conditioned on a
prompt cue. We further evaluate the modified SAEs using HumanEval and selected SAEBench metrics. While attack effectiveness varies across models and layers, strong backdoor behavior can coexist with relatively small changes in several conventional SAE quality measures. These results establish that SAEs can carry behavioral backdoors without modifying the
language model itself and should therefore be treated as security-sensitive components.
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All authors Enrico Ahlers, Daniel Passon, Tobias Kiecker, Eik Reichmann, Lars Grunske
Artificial Intelligence
RocketAgent: A Long-Horizon Engineering Agent for Multidisciplinary Design of Liquid-Rocket Thrust Chambers
Junxiang He, Runze Mao, Kun He et al. (+4 more)
Liquid-rocket thrust-chamber design involves interdependent analyses in which downstream constraints can require earlier design decisions to be revisited. Managing these dependencies across heterogeneous tools requires consistent design information and coordinated updates throughout the workflow. We present RocketAgent, a long-horizon engineering
agent for multidisciplinary preliminary design of
liquid-rocket thrust chambers. A single plan-owning Coding
Agent coordinates engineering skills for performance sizing, subsystem optimization, geometry generation, and multiphysics assessment. A provenance-aware knowledge graph supports method selection, while a typed Design Intermediate Representation maintains shared parameters, artifacts, and decisions. Revision-aware checks invalidate affected results and block superseded inputs, with consequential changes subject to engineering approval. In a representative simulation-based design, RocketAgent continued from an infeasible cooling search through an engineer-authorized operating-point revision, identified feasible subsystem designs, and coordinated subsequent geometry generation and multiphysics assessment to support final configuration selection. Separate module tests assessed surrogate predictions and nozzle adaptation. A two-configuration comparison across three controlled scenarios verified the expected dependency invalidations and superseded-input blocking before solver execution. The representative case demonstrates sustained coordination across a multidisciplinary design workflow, while the controlled tests establish the behavior of the revision mechanisms supporting that execution.
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All authors Junxiang He, Runze Mao, Kun He, Teng Zhang, Liming Zheng, Ke Xiao, Zhi X. Chen
Artificial Intelligence · Cross-listed from cs.CV
Representation Disentanglement for Fair Chest X-Ray Diagnosis
Yujie Sun, Ruizhe Li and Xiaowu Sun
Deep learning has advanced chest X-ray (CXR) diagnosis, yet demographic biases in learned representations may contribute to performance disparities across intersectional groups. We propose a single-encoder framework combining dual-level decorrelation with prototype-guided cross-group contrastive learning to reduce demographic dependence while accounting for within-class variation. We further propose Demographic Representation
Alignment Reduction (DRAR), a new metric that quantifies the reduction in demographic structure within disease representations. The framework is evaluated on four classification tasks using 34,809 CheXpert test images across eight intersectional groups, defined by age, sex and ethnicity. Compared with empirical risk minimization (ERM), our method reduces the mean equalized-odds gap from 15.41% to 10.86% and the AUC gap from 5.95% to 5.01%. Our method achieves a DRAR of 59.04% relative to ERM, with only a slight decrease in mean AUC. These results demonstrate that representation disentanglement can reduce demographic bias and improve intersectional
fairness. Code is available at \url{https://github.com/06Yujie/Fair-Medical-Imaging}.
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Artificial Intelligence · Cross-listed from cs.LG
MercerFlow: Flow Matching in a Kernel-Induced Latent Space for Probabilistic Forecasting
Ilya Kuleshov, Egor Serov and Alexey Zaytsev
Recent work has shown that probabilistic flow matching for time series forecasting benefits from a data-matched prior. The resulting prior introduces local correlations, which a sequential architecture usually absorbs: a recurrent neural network (RNN), a structured state-space model (S4), or a
Transformer. However, such a backbone costs GPU
memory and time per epoch. A cheaper alternative is MLP-based latent-space flow matching: embed the time series via an invertible map to a single latent vector and learn the flow there, so a tabular MLP can treat the series as a set of features. The relationship between the prior and the choice of linear latent map is understudied in conditional flow matching (CFM) forecasting, yet we found it strongly affects performance. Fixed transforms such as
Fourier or discrete cosine (DCT) are only well-conditioned for Ornstein–Uhlenbeck priors, while a principal-component (PCA) map fit to the data is a strong but training-set-dependent reference sensitive to train–test shift. Instead, we propose to use the Mercer eigenbasis of the prior kernel: it diagonalises the centred covariance exactly, decouples from training data, and adapts to non-stationary and periodic priors. On five GluonTS
benchmarks (ETTh1, ETTh2, Weather, Electricity, Traffic) under a shared protocol with TSFlow, the resulting MLP matches or beats it on CRPS at about $4.7\times$ less training
memory and $3.5\times$–$4.4\times$ less time per epoch.
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Artificial Intelligence · Cross-listed from cs.CL
LightMTP: Lightweight Latent Multi-Token Prediction
Tamara Czinczoll, Julie Kallini, Gerard de Melo et al. (+1 more)
Next-
token prediction (NTP) is the standard pretraining objective for large
language models, yet it provides an explicit training signal only for the immediate next
token, which can lead models to exploit local patterns instead of capturing longer-range structure and ideas. Multi-
token prediction (MTP) addresses this by training models to predict several future
tokens. However, existing MTP methods often introduce a large number of new parameters with limited improvements in downstream performance. Latent MTP approaches address this efficiency issue by encoding future
tokens into a vector representation. However, these approaches usually rely on external helper models for future
token encoding. We propose LightMTP, a lightweight, i.e., parameter-efficient, latent MTP approach that bootstraps the future
token representations from the model's own hidden states. Our two LightMTP variants extend supervision to more future
tokens without requiring the additional computational overhead of conventional MTP nor the external supervision latent MTP normally relies on. LightMTP adds at most 1% extra parameters, retains better performance on general
language modeling
benchmarks, and achieves similar gains in planning, coding, and
reasoning.
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All authors Tamara Czinczoll, Julie Kallini, Gerard de Melo, Chen Shani
Artificial Intelligence · Cross-listed from cs.CL
Differentiable Bit-Widths: Co-optimizing Pruning and Quantization via SVD for Ultra-Efficient LLM Compression
Hankyul Kang and Jongbin Ryu
SVD-based
pruning and quantization have recently emerged as a promising strategy for the ultra-efficient compression of large
language models. In these methods, compression is performed in two stages: components are first truncated, and the remaining ones are subsequently quantized. Although this decoupled pipeline benefits from both
pruning and quantization, it requires separate optimization for each stage and fails to fully exploit their balance, which can lead to suboptimal performance under aggressive compression. To address this limitation, we propose a new LLM compression method that co-optimizes
pruning and quantization in a unified framework. Our key idea is a differentiable method for learning component-wise bit-widths, allowing less important components to be assigned 0-bit precision and pruned away. Notably, our method performs favorably against two-stage baselines, even when subjected to extreme quantization settings ($1.61$ bits) designed for ultra-efficiency. Code: https://github.com/MMAI-Laboratory/DBW.
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Artificial Intelligence
Grounded Joint-Attention Other-Play for Zero-Shot Coordination
Giulia Benintendi, Constantin Ruhdorfer, Fabian Kögel et al. (+1 more)
Joint
attention - the human ability to share a common visual or cognitive focus with others - enables a meeting of minds that lets us coordinate even with unfamiliar partners. In this work we investigate whether equipping AI
agents with a similar mechanism can enable such zero-shot coordination. We introduce Mutual
Attention for zero-shot TEaming (MATE): a novel multi-
agent reinforcement learning method inspired by human joint
attention. MATE encourages
agents to coordinate their actions by aligning their visual
attention on scene-salient objects during the interaction rather than relying on arbitrary partner-dependent conventions established during training. Unlike
symmetry-breaking approaches that merely prevent brittle conventions from emerging, MATE actively promotes coordination through an environment-grounded signal that is naturally shared across partners. We evaluate MATE on three
benchmarks: our Card
Alignment Game, designed to isolate brittle convention formation, and the more challenging Level-Based Foraging and OvercookedV2
benchmarks. Our experiments consistently show that a joint-
attention-inspired signal improves coordination with unknown partners, underlining MATE's potential as a general coordination mechanism that complements and surpasses
symmetry-breaking approaches.
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All authors Giulia Benintendi, Constantin Ruhdorfer, Fabian Kögel, Andreas Bulling
Artificial Intelligence · Cross-listed from cs.CV
Scalable Minimal-Change Learning for Controllable Image Editing
Shuo Chen, Fengming Huang, Yu Yao et al. (+2 more)
Image editing should change only the attributes specified by an instruction while preserving everything else, yet current methods often make unintended changes. We treat this minimal-change principle as an optimization objective for instruction-based editing. Latent L1 regularization is a poor proxy for output locality in modern nonlinear generators and often requires supervision unavailable at scale. We instead optimize edit outcomes with reinforcement learning. An agentic
vision-
language reward model audits each source image, instruction, and edited image for two failure types: unimplemented requested changes and unintended changes. A group-level rubric merges and verifies these issues to provide consistent rewards across candidate edits without per-instruction human annotations. On FLUX.1 Kontext-dev, ARRO raises average EditScore from 5.21 to 5.88 across MinEval, MagicBrush, AnyBench, and Emu-Edit. On 600 evaluation examples, it reduces off-target pixel change by 8.4% relative to the base editor. Reward and SFT controls, blinded human evaluations, and transfer to OmniGen2 provide complementary evidence. Code: https://github.com/Showwwwwwwww/ARRO
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All authors Shuo Chen, Fengming Huang, Yu Yao, Mingming Gong, Tongliang Liu