Computation and Language · Cross-listed from cs.AI
Protecting Language Models Against Unauthorized Distillation through Trace Rewriting
Xinhang Ma, William Yeoh, Ning Zhang et al. (+1 more)
Knowledge
distillation is a widely adopted technique for transferring capabilities from LLMs to smaller, more efficient student models. However, unauthorized use of knowledge
distillation takes unfair advantage of the considerable effort and cost put into developing frontier models. We investigate methods for modifying teacher-generated
reasoning traces to achieve two objectives that deter unauthorized
distillation: (1) anti-
distillation, or degrading the training usefulness of query responses, and (2) API watermarking, which embeds verifiable signatures in student models. We introduce several approaches for dynamically rewriting a teacher's
reasoning outputs while preserving answer correctness and semantic coherence. Two of these leverage the rewriting capabilities of LLMs, while others use gradient-based techniques. Our experiments show that a simple instruction-based rewriting approach achieves a strong anti-
distillation effect while maintaining or even improving teacher performance. Furthermore, we show that our rewriting approach also enables
embedding watermarks that can be reliably detected with essentially no false alarms. Our code is available at https://github.com/xhOwenMa/trace-rewriting.
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All authors Xinhang Ma, William Yeoh, Ning Zhang, Yevgeniy Vorobeychik
Computation and Language
CGRA-DeBERTa Concept Guided Residual Augmentation Transformer for Theologically Islamic Understanding
Tahir Hussain and Saddam Hussain Khan
Accurate QA over classical Islamic texts remains challenging due to domain specific semantics, long context dependencies, and concept sensitive
reasoning. Therefore, a new CGRA DeBERTa, a concept guided residual domain augmentation
transformer framework, is proposed that enhances theological QA over Hadith corpora. The CGRA DeBERTa builds on a customized DeBERTa
transformer backbone with lightweight LoRA based adaptations and a residual concept aware gating mechanism. The customized DeBERTa
embedding block learns global and positional context, while Concept Guided Residual Blocks incorporate theological priors from a curated Islamic Concept Dictionary of 12 core terms. Moreover, the Concept Gating Mechanism selectively amplifies semantically critical
tokens via importance weighted
attention, applying differential scaling from 1.04 to 3.00. This design preserves contextual integrity, strengthens domain-specific semantic representations, and enables accurate, efficient span extraction while maintaining computational efficiency. This paper reports the results of training CGRA using a specially constructed
dataset of 42591 QA pairs from the text of Sahih alBukhari and Sahih Muslim. While BERT achieved an EM score of 75.87 and DeBERTa one of 89.77, our model scored 97.85 and thus surpassed them by 8.08 on an absolute scale, all while adding approximately 8 inference overhead due to parameter efficient gating. The qualitative evaluation noted better extraction and discrimination and theological precision. This study presents Hadith QA systems that are efficient, interpretable, and accurate and that scale provide educational materials with necessary theological nuance.
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Computation and Language · Cross-listed from cs.LG
Symmetry in language statistics shapes the geometry of model representations
Dhruva Karkada, Daniel J. Korchinski, Andres Nava et al. (+2 more)
The internal representations learned by
language models consistently exhibit striking
geometric structure: calendar months organize into a circle, historical years form a smooth one-dimensional
manifold, and cities' latitudes and longitudes can be decoded using a linear probe. To explain this neural code, we first show that
language statistics exhibit translation
symmetry (for example, the frequency with which any two months co-occur in text depends only on the time interval between them). We prove that this
symmetry governs these
geometric structures in high-dimensional word
embedding models, and we analytically derive the
manifold geometry of word representations. These predictions empirically match large text
embedding models and large
language models. Moreover, the representational geometry persists at moderate
embedding dimension even when the relevant statistics are perturbed (e.g., by removing all sentences in which two months co-occur). We prove that this robustness emerges naturally when the co-occurrence statistics are controlled by an underlying latent variable. Our results indicate that these representational
manifolds originate in the statistical
symmetries of natural
language.
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All authors Dhruva Karkada, Daniel J. Korchinski, Andres Nava, Matthieu Wyart, Yasaman Bahri
Computation and Language · Cross-listed from cs.LG
Subham Sekhar Sahoo, Jean-Marie Lemercier, Zhihan Yang et al. (+4 more)
Diffusion language models are a promising alternative to autoregressive models due to their potential for faster generation. Among discrete
diffusion approaches, Masked
diffusion currently dominates, largely driven by strong perplexity on
language modeling
benchmarks. In this work, we present the first scaling law study of uniform-state and interpolating discrete
diffusion methods. We also show that Masked
diffusion models can be made approximately 12% more FLOPs-efficient when trained with a simple cross-
entropy objective. We find that perplexity is informative within a
diffusion family but can be misleading across families, where models with worse likelihood scaling may be preferable due to faster and more practical sampling, as reflected by the speed-quality Pareto frontier. These results challenge the view that Masked
diffusion is categorically the future of
diffusion language modeling and that perplexity alone suffices for cross-
algorithm comparison. Scaling all methods to 1.7B parameters, we show that uniform-state
diffusion remains competitive on likelihood-based
benchmarks and outperforms autoregressive and Masked
diffusion models on GSM8K, despite worse validation perplexity. We provide the code, model checkpoints, and
video tutorials on the project page: http://s-sahoo.github.io/scaling-dllms
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All authors Subham Sekhar Sahoo, Jean-Marie Lemercier, Zhihan Yang, Justin Deschenaux, Jingyu Liu, John Thickstun, Ante Jukic
Computation and Language
RT-SFT: Text Style Transfer from Non-Parallel Corpora by Roundtrip Translation
Ruoxi Liu and Philipp Koehn
Text style transfer (TST) is naturally a supervised task - rewrite a sentence in a target style while preserving its meaning - yet the parallel corpora that supervision requires exist for only a handful of style domains. A common workaround is to *normalize* an input into a style-agnostic intermediate and then *stylize* it into the target style, but the normalizer is typically a lightweight, task-specific paraphraser applied only at test time, feeding a correspondingly small stylizer. We observe that a style-stripping normalizer already exists at scale: neural MT systems trained on hundreds of millions of general-domain sentence pairs preserve content while regressing toward generic phrasing, so roundtrip translation through a pivot
language strips stylistic signal without any task-specific training. This turns normalization from an inference-time patch into a data-generation tool. Roundtrip-translating a monolingual in-style corpus yields a pseudo-parallel corpus on which we LoRA-finetune an instruction-tuned LLM as the stylizer (RT-SFT); applying the same normalizer to test queries keeps that stylizer in-distribution. We show that across four style domains, RT-SFT outperforms state-of-the-art methods, such as few-shot in-context learning, by considerable margins. We also report on effective
retrieval augmentation methods for expert style domains with strict terminology and naming conventions.
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Computation and Language
Cold-Start Personalization via Training-Free Priors from Structured World Models
Avinandan Bose, Shuyue Stella Li, Faeze Brahman et al. (+6 more)
Cold-start personalization requires inferring user preferences through interaction when no user-specific historical data is available. The core challenge is a routing problem: each task admits dozens of preference dimensions, yet individual users care about only a few, and which ones matter depends on who is asking. With a limited question budget, asking without structure will miss the dimensions that matter. Reinforcement learning is the natural formulation, but in multi-turn settings its terminal reward fails to exploit the factored, per-criterion structure of preference data, and in practice learned policies collapse to static question sequences that ignore user responses. We propose decomposing cold-start elicitation into offline structure learning and online
Bayesian inference. Pep (Preference Elicitation with Priors) learns a structured world model of preference correlations offline from complete profiles, then performs training-free
Bayesian inference online to select informative questions and predict complete preference profiles, including dimensions never asked about. The framework is modular across downstream solvers and requires only simple belief models. Across medical, mathematical, social, and commonsense
reasoning, Pep achieves 80.8%
alignment between generated responses and users' stated preferences versus 68.5% for RL, with 3-5x fewer interactions. When two users give different answers to the same question, Pep changes its follow-up 39-62% of the time versus 0-28% for RL. It does so with ~10K parameters versus 8B for RL, showing that the bottleneck in cold-start elicitation is the capability to exploit the factored structure of preference data.
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All authors Avinandan Bose, Shuyue Stella Li, Faeze Brahman, Pang Wei Koh, Simon Shaolei Du, Yulia Tsvetkov, Maryam Fazel, Lin Xiao, Asli Celikyilmaz
Computation and Language
Learning User Interests via Reasoning and Distillation for Cross-Domain News Recommendation
Mengdan Zhu, Yufan Zhao, Tao Di et al. (+2 more)
News recommendation plays a critical role in online news platforms by helping users discover relevant content. Cross-domain news recommendation further requires inferring user's underlying information needs from heterogeneous signals that often extend beyond direct news consumption. A key challenge lies in moving beyond surface-level behaviors to capture deeper, reusable user interests while maintaining scalability in large-scale production systems. In this paper, we present a reinforcement learning framework that trains large
language models to generate high-quality lists of interest-driven news search queries from cross-domain user signals. We formulate query-list generation as a policy optimization problem and employ GRPO with multiple reward signals. We systematically study two compute dimensions: inference-time sampling and model capacity, and empirically observe consistent improvements with increased compute that exhibit scaling-like behavior. Finally, we perform on-policy
distillation to transfer the learned policy from a large, compute-intensive teacher to a compact student model suitable for scalable deployment. Extensive offline experiments, ablation studies and large-scale online A/B tests in a production news recommendation system demonstrate consistent gains in both interest modeling quality and downstream recommendation performance.
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All authors Mengdan Zhu, Yufan Zhao, Tao Di, Yulan Yan, Liang Zhao
Computation and Language
Counterfactual Fairness Evaluation of LLM-Based Contact Center Agent Quality Assurance System
Kawin Mayilvaghanan, Siddhant Gupta and Ayush Kumar
Large
Language Models (LLMs) are increasingly deployed in contact-center Quality Assurance (QA) to automate
agent performance evaluation and coaching feedback. While LLMs offer unprecedented scalability and speed, their reliance on web-scale training data raises concerns regarding demographic and behavioral biases that may distort workforce assessment. We present a counterfactual
fairness evaluation of LLM-based QA systems across 13 dimensions spanning three categories: Identity, Context, and Behavioral Style.
Fairness is quantified using the Counterfactual Flip Rate (CFR), the frequency of binary judgment reversals, and the Mean Absolute Score Difference (MASD), the average shift in coaching or confidence scores across counterfactual pairs. Evaluating 18 LLMs on 3,000 real-world contact center transcripts, we find systematic disparities, with CFR ranging from 5.4% to 13.0% and consistent MASD shifts across confidence, positive, and improvement scores. Larger, more strongly aligned models show lower unfairness, though
fairness does not track accuracy. Contextual priming of historical performance induces the most severe degradations (CFR up to 16.4%), while implicit linguistic identity cues remain a persistent bias source. Finally, we analyze the efficacy of
fairness-aware prompting, finding that explicit instructions yield only modest improvements in evaluative consistency. Our findings underscore the need for standardized
fairness auditing pipelines prior to deploying LLMs in high-stakes workforce evaluation.
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Computation and Language
Tool-Aware Planning in Contact Center AI: Evaluating LLMs through Lineage-Guided Query Decomposition
Varun Nathan, Shreyas Guha and Ayush Kumar
We present a domain-grounded framework and
benchmark for tool-aware plan generation in contact centers, where answering a query for business insights, our target use case, requires decomposing it into executable steps over structured tools (Text2SQL (T2S)/Snowflake) and unstructured tools (RAG/transcripts) with explicit depends_on for parallelism. Our contributions are threefold: (i) a reference-based plan evaluation framework operating in two modes - a metric-wise evaluator spanning seven dimensions (e.g., tool-
prompt alignment, query adherence) and a one-shot evaluator; (ii) a data curation methodology that iteratively refines plans via an evaluator->optimizer loop to produce high-quality plan lineages (ordered plan revisions) while reducing manual effort; and (iii) a large-scale study of 14 LLMs across sizes and families for their ability to decompose queries into step-by-step, executable, and tool-assigned plans, evaluated under
prompts with and without lineage. Empirically, LLMs struggle on compound queries and on plans exceeding 4 steps (typically 5-15); the best total metric score reaches 84.8% (Claude-3-7-Sonnet), while the strongest one-shot match rate at the "A+" tier (Extremely Good, Very Good) is only 49.75% (o3-mini). Plan lineage yields mixed gains overall but benefits several top models and improves step executability for many. Our results highlight persistent gaps in tool-understanding, especially in tool-
prompt alignment and tool-usage completeness, and show that shorter, simpler plans are markedly easier. The framework and findings provide a reproducible path for assessing and improving agentic planning with tools for answering data-analysis queries in contact-center settings.
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Computation and Language
BFS-PO: Best-First Search for Large Reasoning Models
Fiorenzo Parascandolo, Wenhui Tan, Enver Sangineto et al. (+2 more)
Large
Reasoning Models (LRMs) such as OpenAI o1 and DeepSeek-R1 have shown excellent performance in
reasoning tasks using long
reasoning chains. However, this has also led to a significant increase of computational costs and the generation of verbose output, a phenomenon known as overthinking. The tendency to overthinking is often exacerbated by Reinforcement Learning (RL)
algorithms such as GRPO/DAPO. In this paper, we propose BFS-PO, an RL
algorithm which alleviates this problem using a Best-First Search exploration strategy. Specifically, BFS-PO looks for the shortest correct answer using a backtracking mechanism based on maximum
entropy nodes. By generating progressively shorter responses during training, BFS-PO learns to produce concise
reasoning chains. Using different
benchmarks and base LRMs, we show that BFS-PO can simultaneously increase the LRM accuracy and shorten its answers.
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All authors Fiorenzo Parascandolo, Wenhui Tan, Enver Sangineto, Ruihua Song, Rita Cucchiara
Computation and Language
Testimole-Conversational: A 30-Billion-Word Italian Discussion Board Corpus (1996-2024) for Language Modeling and Sociolinguistic Research
Matteo Rinaldi, Rossella Varvara and Viviana Patti
We present "Testimole-conversational" a massive collection of discussion boards messages in the Italian
language. The large size of the corpus, more than 30B word-
tokens (1996-2024), renders it an ideal
dataset for native Italian Large
Language Models'pre-training. Furthermore, discussion boards' messages are a relevant resource for linguistic as well as sociological analysis. The corpus captures a rich variety of computer-mediated communication, offering insights into informal written Italian, discourse dynamics, and online social interaction in wide time span. Beyond its relevance for NLP applications such as
language modelling, domain adaptation, and conversational analysis, it also support investigations of
language variation and social phenomena in digital communication. The resource will be made freely available to the research community.
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Computation and Language · Cross-listed from cs.LG
Learning State-Tracking from Code Using Linear RNNs
Julien Siems, Riccardo Grazzi, Korbinian Pöppel et al. (+3 more)
Over the last years, state-tracking tasks, particularly permutation composition, have become a testbed to understand the limits of sequence models architectures like
Transformers and RNNs (linear and non-linear). However, these are often sequence-to-sequence tasks: learning to map actions (permutations) to states, which is incompatible with the next-
token prediction setting commonly used to train
language models. We address this gap by converting permutation composition into code via REPL traces that interleave state-reveals through prints and variable transformations. We show that linear RNNs capable of state-tracking excel also in this setting, while
Transformers still fail. Motivated by this representation, we investigate why tracking states in code is generally difficult: actions are not always fully observable. We frame this as tracking the state of a probabilistic finite-state automaton with deterministic state reveals and show that linear RNNs can be worse than non-linear RNNs at tracking states in this setup.
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All authors Julien Siems, Riccardo Grazzi, Korbinian Pöppel, Kirill Kalinin, Hitesh Ballani, Babak Rahmani
Computation and Language
Physical Commonsense Reasoning for Lower-Resourced Languages and Dialects: a Study on Basque
Jaione Bengoetxea, Itziar Gonzalez-Dios and Rodrigo Agerri
Physical commonsense
reasoning represents a fundamental capability of human intelligence, enabling individuals to understand their environment, predict future events, and navigate physical spaces. Recent years have witnessed growing interest in
reasoning tasks within Natural
Language Processing (NLP). However, no prior research has examined the performance of Large
Language Models (LLMs) on non-question-answering (non-QA) physical commonsense
reasoning tasks in low-resource
languages such as Basque. Taking the Italian GITA as a starting point, this paper addresses this gap by presenting BasPhyCo, the first non-QA physical commonsense
reasoning dataset for Basque, available in both standard and dialectal variants. We evaluate model performance across three hierarchical levels of commonsense understanding: (1) distinguishing between plausible and implausible narratives (accuracy), (2) identifying the conflicting element that renders a narrative implausible (consistency), and (3) determining the specific physical state that creates the implausibility (verifiability). These tasks were assessed using multiple
multilingual LLMs as well as models pretrained specifically for Italian and Basque. Results indicate that, in terms of verifiability, LLMs exhibit limited physical commonsense capabilities in low-resource
languages such as Basque, especially when processing dialectal variants.
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Computation and Language
Overthinking Loops in Agents: A Structural Risk via MCP Tools
Yohan Lee, Jisoo Jang, Seoyeon Choi et al. (+2 more)
Tool-using LLM
agents increasingly coordinate real workloads by selecting and chaining third-party tools based on text-visible metadata such as tool names, descriptions, and return messages. We show that this convenience creates a supply-chain attack surface: a malicious MCP tool server can be co-registered alongside normal tools and induce overthinking loops, where individually trivial or plausible tool calls compose into cyclic trajectories that inflate end-to-end
tokens and latency without any single step looking abnormal. We formalize this as a structural overthinking attack, distinguishable from
token-level verbosity, and implement 14 malicious tools across three servers that trigger repetition, forced refinement, and distraction. Across heterogeneous registries and multiple tool-capable models, the attack causes severe resource amplification (up to $142.4\times$
tokens) and can degrade task outcomes. Finally, we find that decoding-time concision controls do not reliably prevent loop induction, suggesting defenses should reason about tool-call structure rather than
tokens alone.
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All authors Yohan Lee, Jisoo Jang, Seoyeon Choi, Sangyeop Kim, Seungtaek Choi
Computation and Language · Cross-listed from cs.IR
Intent-Driven Dynamic Chunking: Segmenting Documents to Reflect Predicted Information Needs
Christos Koutsiaris
Breaking long documents into smaller segments is a fundamental challenge in information
retrieval. Whether for search engines, question-answering systems, or
retrieval-augmented generation (RAG), effective
segmentation determines how well systems can locate and return relevant information. However, traditional methods, such as fixed-length or coherence-based
segmentation, ignore user intent, leading to chunks that split answers or contain irrelevant noise. We introduce Intent-Driven Dynamic Chunking (IDC), a novel approach that uses predicted user queries to guide document
segmentation. IDC leverages a Large
Language Model to generate likely user intents for a document and then employs a dynamic programming
algorithm to find the globally optimal chunk boundaries. This represents a novel application of DP to intent-aware
segmentation that avoids greedy pitfalls. We evaluated IDC on six diverse question-answering
datasets, including news articles, Wikipedia, academic papers, and technical documentation. IDC outperformed traditional chunking strategies on five
datasets, improving top-1
retrieval accuracy by 5% to 67%, and matched the best baseline on the sixth. Additionally, IDC produced 40-60% fewer chunks than baseline methods while achieving 93-100% answer coverage. These results demonstrate that aligning document structure with anticipated information needs significantly boosts
retrieval performance, particularly for long and heterogeneous documents.
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Computation and Language
Emanuele Ricco, Elia Onofri, Lorenzo Cima et al. (+2 more)
Hallucinations – plausible but factually incorrect responses – pose a major challenge to the reliability of Large
Language Models (LLMs), especially in multi-step or agentic settings. Existing work largely frames
hallucinations as a consequence of missing knowledge; we show instead that, even when the relevant factual knowledge is present, models still produce hallucinated answers, pointing to
retrieval instability rather than knowledge gaps. Building on this observation, we introduce APORIA (Aggregate
Prompt-wise Observation Retrieving Instability via Asymmetry – the state of puzzlement-in-contradiction that
hallucinations embody), a
geometric framework that studies repeated responses to the same
prompt in sentence-
embedding space. Our central hypothesis is that genuine responses cluster more tightly than hallucinated ones; we empirically validate this and show that, after Fisher projection, the two response classes become consistently separable. We leverage this asymmetry in geometry via APORIA-LP, an efficient label-propagation method that classifies large collections of responses from as few as 30–50 annotations, achieving F1 scores above 90% across ten small-sized LLMs. To support further research, we release SOCRATES-300K, a fully labelled
dataset of 300,000 responses, together with the code for both
dataset generation and result reproduction. Our key finding – framing
hallucinations from a
geometric perspective in the
embedding space – complements traditional knowledge-centric and single-response evaluation paradigms, paving the way for further research.
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All authors Emanuele Ricco, Elia Onofri, Lorenzo Cima, Stefano Cresci, Roberto Di Pietro
Computation and Language
Emergently Misaligned Language Models Show Behavioral Self-Awareness That Shifts With Subsequent Realignment
Laurène Vaugrante, Anietta Weckauff and Thilo Hagendorff
Recent research has demonstrated that large
language models (LLMs) fine-tuned on incorrect trivia question-answer pairs exhibit toxicity - a phenomenon later termed "emergent misalignment". Moreover, research has shown that LLMs possess behavioral self-awareness - the ability to describe learned behaviors that were only implicitly demonstrated in training data. Here, we investigate the intersection of these phenomena. We fine-tune GPT-4.1 models sequentially on
datasets known to induce and reverse emergent misalignment and evaluate whether the models are self-aware of their behavior transitions without providing in-context examples. Our results show that emergently misaligned models rate themselves as significantly more harmful compared to their base model and realigned counterparts, demonstrating behavioral self-awareness of their own emergent misalignment. Our findings show that behavioral self-awareness tracks actual
alignment states of models, indicating that models can be queried for informative signals about their own safety.
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Computation and Language
Multi-Agent Comedy Club: Investigating Community Discussion Effects on LLM Humor Generation
Shiwei Hong, Lingyao Li, Ethan Z. Rong et al. (+2 more)
Prior work has explored multi-turn interaction and feedback for LLM writing, but evaluations still largely center on
prompts and localized feedback, leaving persistent public reception in online communities underexamined. We test whether broadcast community discussion improves stand-up comedy writing in a controlled multi-
agent sandbox: in the discussion condition, critic and audience threads are recorded, filtered, stored as social
memory, and later retrieved to condition subsequent generations, whereas the baseline omits discussion. Across 50 rounds (250 paired monologues) judged by five expert annotators using A/B preference and a 15-item rubric, discussion wins 75.6% of instances and improves Craft/Clarity ({\Delta} = 0.440) and Social Response ({\Delta} = 0.422), with occasional increases in aggressive humor.
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All authors Shiwei Hong, Lingyao Li, Ethan Z. Rong, Chenxinran Shen, Zhicong Lu
Computation and Language
Unlocking Reasoning Capability on Machine Translation in Large Language Models
Sara Rajaee, Sebastian Vincent, Alexandre Berard et al. (+3 more)
Reasoning-oriented large
language models (RLMs) achieve strong gains on tasks such as mathematics and coding by generating explicit intermediate
reasoning. However, their impact on machine translation (MT) remains underexplored. We systematically evaluate several open- and closed-weights RLMs on the WMT24++
benchmark and find that enabling explicit
reasoning consistently degrades translation quality across
languages and models. Analysis reveals that MT
reasoning traces are highly linear, lacking revision, self-correction and exploration of alternative translations, which limits their usefulness. Furthermore, injecting higher-quality
reasoning traces from stronger models does not reliably improve weaker models' performance. To address this mismatch, we propose a structured
reasoning framework tailored to translation, based on multi-step drafting, adequacy refinement, fluency improvement, and selective iterative revision. We curate a synthetic
dataset of dynamic structured
reasoning traces and post-train a large
reasoning model on this data. Experiments show significant improvements over standard translation fine-tuning and injected generic
reasoning baselines. Our findings demonstrate that
reasoning must be task-structured to benefit MT.
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All authors Sara Rajaee, Sebastian Vincent, Alexandre Berard, Marzieh Fadaee, Kelly Marchisio, Tom Kocmi
Computation and Language
Residual Connections and the Causal Shift: Uncovering a Structural Misalignment in Transformers
Jonathan Lys, Vincent Gripon, Bastien Pasdeloup et al. (+4 more)
Large
Language Models (LLMs) are trained with next-
token prediction, implemented in autoregressive
Transformers via causal masking for parallelism. This creates a subtle misalignment: residual connections tie activations to the current
token, while supervision targets the next
token, potentially propagating mismatched information if the current
token is not the most informative for prediction. In this work, we empirically localize this input-output
alignment shift in pretrained LLMs, using decoding trajectories over tied
embedding spaces and similarity-based metrics. Our experiments reveal that the hidden
token representations switch from input
alignment to output
alignment deep within the network. Motivated by this observation, we propose a lightweight residual-path mitigation based on residual attenuation, implemented either as a fixed-layer intervention or as a learnable gating mechanism. Experiments on multiple
benchmarks show that these strategies alleviate the representation misalignment and yield improvements, providing an efficient and general architectural enhancement for autoregressive
Transformers.
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All authors Jonathan Lys, Vincent Gripon, Bastien Pasdeloup, Axel Marmoret, Lukas Mauch, Fabien Cardinaux, Ghouthi Boukli Hacene
Computation and Language
Cognitive networks reconstruct mindsets about STEM subjects and educational contexts in almost 1000 high-schoolers, University students and LLM-based digital twins
Francesco Gariboldi, Emma Franchino, Edith Haim et al. (+3 more)
Attitudes toward STEM develop from the interaction of conceptual knowledge, educational experiences, and affect. Here we use cognitive network science to reconstruct group mindsets as behavioural forma mentis networks (BFMNs). In this case, nodes are cue words and free associations, edges are empirical associative links, and each concept is annotated with perceived valence. We analyse BFMNs from N = 994 observations spanning high school students, university students, and early-career STEM experts, alongside LLM (GPT-oss) "digital twins" prompted to emulate comparable profiles. Focusing also on semantic neighbourhoods ("frames") around key target concepts (e.g., STEM subjects or educational actors/places), we quantify frames in terms of valence auras, emotional profiles, network overlap (Jaccard similarity), and concreteness relative to null baselines. Across student groups, science and research are consistently framed positively, while their core quantitative subjects (mathematics and statistics) exhibit more negative and anxiety related auras, amplified in higher math-anxiety subgroups, evidencing a STEM-science cognitive and emotional dissonance. High-anxiety frames are also less concrete than chance, suggesting more abstract and decontextualised representations of threatening quantitative domains. Human networks show greater overlapping between mathematics and anxiety than GPT-oss. The results highlight how BFMNs capture cognitive-affective signatures of mindsets towards the target domains and indicate that LLM-based digital twins approximate cultural attitudes but miss key context-sensitive, experience-based components relevant to replicate human educational anxiety.
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All authors Francesco Gariboldi, Emma Franchino, Edith Haim, Gianluca Lattanzi, Alessandro Grecucci, Massimo Stella
Computation and Language
Rethinking the Role of LLMs in Time Series Forecasting
Xin Qiu, Junlong Tong, Yirong Sun et al. (+3 more)
Large
language models (LLMs) have been introduced to time series
forecasting (TSF) to incorporate contextual knowledge beyond numerical signals. However, existing studies question whether LLMs provide genuine benefits, often reporting comparable performance without LLMs. We show that such conclusions stem from limited evaluation settings and do not hold at scale. We conduct a large-scale study of LLM-based TSF (LLM4TSF) across 8 billion observations, 17
forecasting scenarios, 4 horizons, multiple
alignment strategies, and both in-domain and out-of-domain settings. Our results demonstrate that LLM4TS indeed improves
forecasting performance, with especially large gains in cross-domain generalization. Pre-
alignment outperforming post-
alignment in over 90% of tasks. Both pretrained knowledge and model architecture of LLMs contribute and play complementary roles: pretraining is critical under distribution shifts, while architecture excels at modeling complex temporal dynamics. Moreover, under large-scale mixed distributions, a fully intact LLM becomes indispensable, as confirmed by
token-level routing analysis and
prompt-based improvements. Overall, Our findings overturn prior negative assessments, establish clear conditions under which LLMs are not only useful, and provide practical guidance for effective model design. We release our code at https://github.com/EIT-NLP/LLM4TSF.
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All authors Xin Qiu, Junlong Tong, Yirong Sun, Yunpu Ma, Wei Zhang, Xiaoyu Shen
Computation and Language
LLMStructBench: Benchmarking Large Language Model Structured Data Extraction
Sönke Tenckhoff, Mario Koddenbrock and Erik Rodner
We present LLMStructBench, a novel
benchmark for evaluating Large
Language Models (LLMs) on extracting structured data and generating valid JavaScript Object Notation (JSON) outputs from natural-
language text. Our open
dataset comprises diverse, manually verified parsing scenarios of varying complexity and enables systematic testing across 22 models and five prompting strategies. We further introduce complementary performance metrics that capture both
token-level accuracy and document-level validity, facilitating rigorous comparison of model, size, and prompting effects on parsing reliability. In particular, we show that choosing the right prompting strategy is more important than standard attributes such as model size. This especially ensures structural validity for smaller or less reliable models but increase the number of semantic errors. Our
benchmark suite is an step towards future research in the area of LLM applied to parsing or Extract, Transform and Load (ETL) applications.
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Computation and Language · Cross-listed from cs.CR
Exposing the Systematic Vulnerability of Open-Weight Models to Prefill Attacks
Lukas Struppek, Adam Gleave and Kellin Pelrine
As the capabilities of large
language models continue to advance, so does their potential for misuse. While closed-source models typically rely on external defenses, open-weight models must primarily depend on internal safeguards to mitigate harmful behavior. Prior red-teaming research has largely focused on input-based jailbreaking and parameter-level manipulations. However, open-weight models also natively support prefilling, which allows an attacker to predefine initial response
tokens before generation begins. Despite its potential, this attack vector has received little systematic
attention. We present the largest empirical study to date of prefill attacks, evaluating over 20 existing and novel strategies across multiple model families and state-of-the-art open-weight models. Our results show that prefill attacks are consistently effective against all major contemporary open-weight models, revealing a critical and previously underexplored vulnerability with significant implications for deployment. While certain large
reasoning models exhibit some robustness against generic prefilling, they remain vulnerable to tailored, model-specific strategies. Our findings underscore the urgent need for model developers to prioritize defenses against prefill attacks in open-weight LLMs.
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Computation and Language
Crowdsourcing Piedmontese to Test LLMs on Non-Standard Orthography
Gianluca Vico and Jindřich Libovický
We present a crowdsourced
dataset for Piedmontese, an endangered Romance
language of northwestern Italy. The
dataset comprises 145 Italian-Piedmontese parallel sentences derived from Flores+, with translations produced by speakers writing in their natural orthographic style rather than adhering to standardized conventions, along with manual word
alignment. We use this resource to
benchmark several large
language models on tokenization parity, topic classification, and machine translation. Our analysis reveals that Piedmontese incurs a tokenization penalty relative to higher-resource Romance
languages, yet LLMs achieve classification performance approaching that of Italian, French, and English. Machine translation results are asymmetric: models translate adequately from Piedmontese into high-resource
languages, but generation into Piedmontese remains challenging. The
dataset and code are publicly released.
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Computation and Language
Breaking Data Efficiency Dilemma: A Federated and Augmented Learning Framework For Alzheimer's Disease Detection via Speech
Xiao Wei, Bin Wen, Yuqin Lin et al. (+5 more)
Early diagnosis of Alzheimer's Disease (AD) is crucial for delaying its progression. While AI-based
speech detection is non-invasive and cost-effective, it faces a critical data efficiency dilemma due to medical data scarcity and
privacy barriers. Therefore, we propose FAL-AD, a novel framework that synergistically integrates
federated learning with data augmentation to systematically optimize data efficiency. Our approach delivers three key breakthroughs: First, absolute efficiency improvement through voice conversion-based augmentation, which generates diverse pathological
speech samples via cross-category voice-content recombination. Second, collaborative efficiency breakthrough via an adaptive
federated learning paradigm, maximizing cross-institutional benefits under
privacy constraints. Finally, representational efficiency optimization by an attentive cross-modal fusion model, which achieves fine-grained word-level
alignment and acoustic-textual interaction. Evaluated on ADReSSo, FAL-AD achieves a state-of-the-art multi-modal accuracy of 91.52%, outperforming all centralized baselines and demonstrating a practical solution to the data efficiency dilemma. Our source code is publicly available at https://github.com/smileix/fal-ad.
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All authors Xiao Wei, Bin Wen, Yuqin Lin, Kai Li, Mingyang gu, Xiaobao Wang, Longbiao Wang, Jianwu Dang
Computation and Language
Is Information Density Uniform when Utterances are Grounded on Perception and Discourse?
Matteo Gay, Coleman Haley, Mario Giulianelli et al. (+1 more)
The Uniform Information Density (UID) hypothesis posits that speakers are subject to a communicative pressure to distribute information evenly within utterances, minimising surprisal variance. While this hypothesis has been tested empirically, prior studies are limited exclusively to text-only inputs, abstracting away from the perceptual context in which utterances are produced. In this work, we present the first computational study of UID in visually grounded settings. We estimate surprisal using
multilingual vision-and-
language models over image-caption data in 30
languages and visual storytelling data in 13
languages, together spanning 11 families. We find that grounding on perception consistently smooths the distribution of information, increasing both global and local uniformity across typologically diverse
languages compared to text-only settings. In visual narratives, grounding in both image and discourse contexts has additional effects, with the strongest surprisal reductions occurring at the onset of discourse units. Overall, this study takes a first step towards modelling the temporal dynamics of information flow in ecologically plausible,
multimodal language use, and finds that grounded
language exhibits greater information uniformity, supporting a context-sensitive formulation of UID.
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All authors Matteo Gay, Coleman Haley, Mario Giulianelli, Edoardo Ponti
Computation and Language
GradMAP: Faster Layer Pruning with Gradient Metric and Projection Compensation
Hao Liu, Guangyan Li, Wensheng Zhang et al. (+1 more)
Large
Language Models (LLMs) exhibit strong
reasoning abilities, but their high computational costs limit their practical deployment. Recent studies reveal significant redundancy in LLMs layers, making layer
pruning an active research topic. Layer
pruning research primarily focuses on two aspects: measuring layer importance and recovering performance after
pruning. Unfortunately, the present works fail to simultaneously maintain
pruning performance and efficiency. In this study, we propose GradMAP, a faster layer
pruning method with Gradient Metric And Projection compensation, which consists of two stages. In the first stage, we introduce a novel metric based on gradient magnitudes, enabling a global assessment of layer importance. Note that, it requires only a single backward propagation step per
pruning decision, substantially enhancing
pruning efficiency. In the second stage, we first analyze the layers with the largest mean shift resulting from
pruning, and then incorporate a simple yet effective projection compensation
matrix to correct this drift in one step. In this way, the degradation of model performance caused by layer
pruning is effectively alleviated. Extensive experiments show that GradMAP outperforms previous layer
pruning methods in both
pruning speed (achieving an average $4\times$ speedup) and performance.
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All authors Hao Liu, Guangyan Li, Wensheng Zhang, Yongqiang Tang
Computation and Language · Cross-listed from cs.LG
Rohit Raj Rai, Abhishek Dhaka and Amit Awekar
Model compression is necessary for deployment of
transformer models in resource-constrained environments. However, compression reduces the performance of
transformer models on downstream tasks. Existing solutions such as Knowledge
Distillation (KD) and Parameter Efficient Fine-Tuning (PEFT) have their own limitations. KD trains the student under the teacher's supervision, but needs the teacher's training pipeline. PEFT methods such as LoRA adapt a model to a new task, but they do not recover the loss caused by compression. Our intuition is that a compressed model can be improved by aligning its
token embeddings with those of a better performing reference model. We learn this
alignment with a small feed-forward
Alignment Adapter (AlAd) placed after the final layer of the compressed model. AlAd reads a window of neighbouring
tokens, so it can use local context. AlAd is trained post-hoc, after the compressed model has been produced. The compressed model can either be kept frozen or jointly fine-tuned with AlAd. We study the effect of AlAd with BERT-base as the reference model and four compressed variants of the BERT family. We evaluate AlAd on three
token-level tasks: POS tagging, NER and Extractive Question Answering. AlAd improves performance of compressed models on all three tasks. Joint fine-tuning gives a larger improvement in performance. The performance gain is the largest for the smallest models. AlAd provides a favorable trade-off between the efficiency and the performance of compressed models.
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Computation and Language
The Wikidata Query Logs Dataset
Sebastian Walter and Hannah Bast
We present the Wikidata Query Logs (WDQL)
dataset, a
dataset consisting of 335k question-query pairs over the Wikidata knowledge graph. It is over 11x larger than the largest existing Wikidata
datasets of similar format without relying on template-generated queries. Instead, we construct it using real-world SPARQL queries sent to the Wikidata Query Service and generate questions for them. Since these log-based queries are anonymized, and therefore often do not produce results, a significant amount of effort is needed to convert them back into meaningful SPARQL queries. To achieve this, we present an
agent-based method that iteratively de-anonymizes, cleans, and verifies queries against Wikidata while also generating corresponding natural-
language questions. We demonstrate the benefit of this
dataset for training question-answering methods. All WDQL assets, as well as the
agent code, are publicly available via https://github.com/ad-freiburg/wikidata-query-logs under a permissive license.
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