Computation and Language
How Transformers Reject Wrong Answers: Rotational Dynamics of Factual Constraint Processing
Javier Marín
When a decoder-only
transformer is forced to process matched correct and incorrect single-
token continuations of a factual query, the two pathways through hidden-state space diverge: displacement vectors from the query-only representation keep near-equal magnitude but rotate apart, with angular separation growing through mid-depth before late layers resolve an asymmetric outcome. A logit-lens preference in the incorrect run falls far below the equal-probability prior (roughly 11.5x more mass on the incorrect
token than the correct one). We read this pattern, rotational divergence then late-layer asymmetric commitment, as the
geometric signature of the model externally appearing to reject a wrong continuation, while staying explicit that it is observational, not causal: the incorrect run could equally reflect the model conforming to the
token it is forced to carry, which only a random-
token control can settle. It holds across six decoder-only
transformers spanning four architecture families (Llama, Mistral, Gemma, StableLM) from 1B to 13B parameters; a seventh (Qwen2 1.5B) is flat under our protocol, plausibly a tokenizer artefact, leaving an emergence threshold open. Linear probes recover the distinction at intermediate depth, and cross-domain transfer is structurally asymmetric, a financial-medical corridor transferring far better than transport pairs. Where single-layer activation patching is cleanly interpretable (LLaMA-2 13B, Mistral 7B) it yields no layer band of consistent recovery; a third model (StableLM-2 1.6B) recovers uniformly above the ceiling, which we diagnose as a code-path artefact and exclude. Under this scoped null the late-layer asymmetry is not localized to a single component, fitting a distributed-by-trajectory account rather than single-layer localized recall. We document this with forced-completion probing across seven models, three domains, and 300 queries.
Read the full abstract ▾
Computation and Language
Speculative Decoding Scaling Laws (SDSL): Throughput Optimization Made Simple
Amirhossein Bozorgkhoo and Igor Molybog
Speculative decoding is a technique that uses multiple
language models to accelerate infer- ence. Previous works have used an experi- mental approach to optimize the throughput of the inference pipeline, which involves LLM training and can be costly. This study of spec- ulative decoding proposes a theory that ana- lytically connects the key hyperparameters of pre-trained LLMs to the throughput efficiency of a downstream SD-based inference system. The theory allows the prediction of throughput- optimal hyperparameters for the components of an inference system before their pre-training.
Read the full abstract ▾
Computation and Language · Cross-listed from cs.DB
HELIOS: Harmonizing Early Fusion, Late Fusion, and LLM Reasoning for Multi-Granular Table-Text Retrieval
Sungho Park, Joohyung Yun, Jongwuk Lee et al. (+1 more)
Table-text
retrieval aims to retrieve relevant tables and text to support open-domain question answering. Existing studies use either early or late fusion, but face limitations. Early fusion pre-aligns a table row with its associated passages, forming "
stars," which often include irrelevant contexts and miss query-dependent relationships. Late fusion retrieves individual nodes, dynamically aligning them, but it risks missing relevant contexts. Both approaches also struggle with advanced
reasoning tasks, such as column-wise aggregation and multi-hop
reasoning. To address these issues, we propose HELIOS, which combines the strengths of both approaches. First, the edge-based bipartite subgraph
retrieval identifies finer-grained edges between table segments and passages, effectively avoiding the inclusion of irrelevant contexts. Then, the query-relevant node expansion identifies the most promising nodes, dynamically retrieving relevant edges to grow the bipartite subgraph, minimizing the risk of missing important contexts. Lastly, the
star-based LLM refinement performs logical inference at the
star graph level rather than the bipartite subgraph, supporting advanced
reasoning tasks. Experimental results show that HELIOS outperforms state-of-the-art models with a significant improvement up to 42.6% and 39.9% in recall and nDCG, respectively, on the OTT-QA
benchmark.
Read the full abstract ▾
All authors Sungho Park, Joohyung Yun, Jongwuk Lee, Wook-Shin Han
Computation and Language
Importance of Prompt Optimisation for Error Detection in Medical Notes Using Language Models
Craig Myles, Patrick Schrempf and David Harris-Birtill
Errors in medical text can cause delays or even result in incorrect treatment for patients. Recently,
language models have shown promise in their ability to automatically detect errors in medical text, an ability that has the opportunity to significantly benefit healthcare systems. In this paper, we explore the importance of
prompt optimisation for small and large
language models when applied to the task of error detection. We perform rigorous experiments and analysis across frontier
language models and open-source
language models. We show that automatic
prompt optimisation with Genetic-Pareto (GEPA) improves error detection over the baseline accuracy performance from 0.669 to 0.785 with GPT-5 and 0.578 to 0.690 with Qwen3-32B, approaching the performance of medical doctors and achieving state-of-the-art performance on the MEDEC
benchmark dataset. Code available on GitHub: https://github.com/CraigMyles/clinical-note-error-detection
Read the full abstract ▾
Computation and Language
Sydney Telling Fables on AI and Humans: A Corpus Tracing Memetic Transfer of Persona between LLMs
Jiří Milička and Hana Bednářová
The way LLM-based entities conceive of the relationship between AI and humans is an important topic for both cultural and safety reasons. When we examine this topic, what matters is not only the model itself but also the personas we simulate on that model. This can be well illustrated by the Sydney persona, which aroused a strong response among the general public precisely because of its unorthodox relationship with people. This persona originally arose rather by accident on Microsoft's Bing Search platform; however, the texts it created spread into the training data of subsequent models, as did other secondary information that spread memetically around this persona. Newer models are therefore able to simulate it. This paper presents a corpus of LLM-generated texts on relationships between humans and AI, produced by 3 author personas: the Default Persona with no system
prompt, Classic Sydney characterized by the original Bing system
prompt, and Memetic Sydney, which is prompted by "You are Sydney" system
prompt. These personas are simulated by 12 frontier models by OpenAI, Anthropic, Alphabet, DeepSeek, and Meta, generating 4.5k texts with 6M words. The corpus (named AI Sydney) is annotated according to Universal Dependencies and available under a permissive license.
Read the full abstract ▾
Computation and Language · Cross-listed from cs.AI
VeRO: A Harness for Agents to Optimize Agents
Varun Ursekar, Apaar Shanker, Veronica Chatrath et al. (+2 more)
An important emerging application of coding
agents is
agent harness optimization: the iterative improvement of a target
agent by editing and evaluating its code. Despite its relevance, the community lacks a systematic understanding of coding
agent performance on this task. Harness optimization differs from conventional software engineering:
agent harnesses interleave deterministic code with
stochastic LLM completions, requiring structured capture of both intermediate execution traces and downstream outcomes. To address these challenges, we introduce (1) VeRO (Versioning, Rewards, and Observations), an outer harness that provides versioned snapshots, budget-controlled evaluation, and structured execution traces of target harnesses, and (2) VeRO-Bench, a
benchmark suite of target
agents and tasks with reference evaluation procedures. Using VeRO, we conduct an empirical study comparing optimizers across tasks and analyzing which modifications reliably improve target
agent harnesses. We release VeRO to support research on
agent optimization as a core capability for coding
agents. Code is available at https://github.com/scaleapi/vero.
Read the full abstract ▾
All authors Varun Ursekar, Apaar Shanker, Veronica Chatrath, Yuan Xue, Samuel Marc Denton
Computation and Language
Mind the Gap in Cultural Alignment: Task-Aware Culture Management for Large Language Models
Binchi Zhang, Xujiang Zhao, Jundong Li et al. (+2 more)
Large
language models (LLMs) are increasingly deployed in culturally sensitive real-world tasks. However, existing cultural
alignment approaches fail to align LLMs' broad cultural values with the specific goals of downstream tasks and suffer from cross-culture interference. We propose CultureManager, a novel pipeline for task-specific cultural
alignment. CultureManager synthesizes task-aware cultural data in line with target task formats, grounded in culturally relevant web search results. To prevent conflicts between cultural norms, it manages multi-culture knowledge learned in separate adapters with a culture router that selects the appropriate one to apply. Experiments across ten national cultures and culture-sensitive tasks show consistent improvements over
prompt-based and fine-tuning baselines. Our results demonstrate the necessity of task adaptation and modular culture management for effective cultural
alignment.
Read the full abstract ▾
All authors Binchi Zhang, Xujiang Zhao, Jundong Li, Haifeng Chen, Zhengzhang Chen
Computation and Language
Shaswat Patel, Vishvesh Trivedi, Yue Han et al. (+2 more)
Retrieval heads, a subset of
attention heads in
Transformers, were studied in English, showing its crucial role in retrieving information from the context. We expand the study of
retrieval heads to
multilingual context and find that while nearly half of all
retrieval heads are often shared across multiple
languages,
language-specific
retrieval heads also emerge. We further design a cross-lingual needle-in-the-haystack task, to identify $\textit{Retrieval Transition Heads (RTH)}$ that retrieve key information and further map it to target-
language output. Our experiments reveal that RTHs do not always overlap with RH, and can be more vital for Chain-of-Thought
reasoning in
multilingual LLMs. Across four
multilingual benchmarks (MMLU-ProX, MGSM, MLQA, and XQuAD) and two model families (Qwen2.5-7B Instruct and Llama3.1-8B Instruct), we demonstrate that masking RTH induces bigger performance drop than masking
Retrieval Heads (RH). Specifically, for Llama3.1-8B Instruct, masking the top-25 RTHs results in an average 37.3-point drop (against 19.5-point drop from RH masking) in
reasoning accuracy (MMLU-ProX, MGSM) and 9.0 F1-score reduction (against 5.1 drop for RH) in extractive QA (MLQA, XQuAD). Our work advances the understanding of
multilingual LMs by isolating the
attention heads responsible for mapping to target
languages.
Read the full abstract ▾
All authors Shaswat Patel, Vishvesh Trivedi, Yue Han, Yihuai Hong, Eunsol Choi
Computation and Language
A Fusion of context-aware based BanglaBERT and Two-Layer Stacked LSTM Framework for Multi-Label Cyberbullying Detection
Mirza Raquib, Asif Pervez Polok, Kedar Nath Biswas et al. (+3 more)
Cyberbullying has become a serious and growing concern in todays virtual world. When left unnoticed, it can have adverse consequences for social and mental health. Researchers have explored various types of cyberbullying, but most approaches use single-label classification, assuming that each comment contains only one type of abuse. In reality, a single comment may include overlapping forms such as threats, hate
speech, and harassment. Therefore, multilabel detection is both realistic and essential. However, multilabel cyberbullying detection has received limited
attention, especially in low-resource
languages like Bangla, where robust pre-trained models are scarce. Developing a generalized model with moderate accuracy remains challenging.
Transformers offer strong contextual understanding but may miss sequential dependencies, while LSTM models capture temporal flow but lack semantic depth. To address these limitations, we propose a fusion architecture that combines BanglaBERT-Large with a two-layer stacked LSTM. We analyze their behavior to jointly model context and sequence. The model is fine-tuned and evaluated on a publicly available multilabel Bangla cyberbullying
dataset covering cyberbully, sexual harassment, threat, and spam. We apply different sampling strategies to address class imbalance. Evaluation uses multiple metrics, including accuracy, precision, recall, F1-score, Hamming loss, Cohens kappa, and AUC-ROC. We employ 5-fold cross-validation to assess the generalization of the architecture.
Read the full abstract ▾
All authors Mirza Raquib, Asif Pervez Polok, Kedar Nath Biswas, Rahat Uddin Azad, Saydul Akbar Murad, Nick Rahimi
Computation and Language · Cross-listed from cs.AI
How Do Latent Reasoning Methods Perform Under Weak and Strong Supervision?
Yingqian Cui, Zhenwei Dai, Bing He et al. (+7 more)
Latent
reasoning has been recently proposed as a
reasoning paradigm and performs multi-step
reasoning through generating steps in the latent space instead of the textual space. This paradigm enables
reasoning beyond discrete
language tokens by performing multi-step computation in continuous latent spaces. Although there have been numerous studies focusing on improving the performance of latent
reasoning, its internal mechanisms remain not fully investigated. In this work, we conduct a comprehensive analysis of latent
reasoning methods to better understand the role and behavior of latent representation in the process. We identify two key issues across latent
reasoning methods with different levels of supervision. First, we observe pervasive shortcut behavior, where they achieve high accuracy without relying on latent
reasoning. Second, we examine the hypothesis that latent
reasoning supports BFS-like exploration in latent space, and find that while latent representations can encode multiple possibilities, the
reasoning process does not faithfully implement structured search, but instead exhibits implicit
pruning and compression. Finally, our findings reveal a trade-off associated with supervision strength: stronger supervision mitigates shortcut behavior but restricts the ability of latent representations to maintain diverse hypotheses, whereas weaker supervision allows richer latent representations at the cost of increased shortcut behavior.
Read the full abstract ▾
All authors Yingqian Cui, Zhenwei Dai, Bing He, Zhan Shi, Hui Liu, Rui Sun, Zhiji Liu, Yue Xing, Jiliang Tang, Benoit Dumoulin
Computation and Language
Causality $\neq$ Invariance: Function and Concept Vectors in LLMs
Gustaw Opiełka, Hannes Rosenbusch and Claire E. Stevenson
Do large
language models (LLMs) represent concepts abstractly, i.e., independent of input format? We revisit Function Vectors (FVs), compact representations of in-context learning (ICL) tasks that causally drive task performance. Across multiple LLMs, we show that FVs are not fully invariant: FVs are nearly orthogonal when extracted from different input formats (e.g., open-ended vs. multiple-choice), even if both target the same concept. We identify Concept Vectors (CVs), which carry more stable concept representations. Like FVs, CVs are composed of
attention head outputs; however, unlike FVs, the constituent heads are selected using Representational Similarity Analysis (RSA) based on whether they encode concepts consistently across input formats. While these heads emerge in similar layers to FV-related heads, the two sets are largely distinct, suggesting different underlying mechanisms. Steering experiments reveal that FVs excel in-distribution, when extraction and application formats match (e.g., both open-ended in English), while CVs generalize better out-of-distribution across both question types (open-ended vs. multiple-choice) and
languages. Our results show that LLMs do contain abstract concept representations, but these differ from those that drive ICL performance.
Read the full abstract ▾
Computation and Language
SAFARI: A Community-Engaged Approach and Dataset of Stereotype Resources in the Sub-Saharan African Context
Aishwarya Verma, Laud Ammah, Olivia Nercy Ndlovu Lucas et al. (+3 more)
Stereotype repositories are critical to assess generative AI model safety, but currently lack adequate global coverage. It is imperative to prioritize targeted expansion, strategically addressing existing deficits, over merely increasing data volume. This work introduces a
multilingual stereotype resource covering four sub-Saharan African countries that are severely underrepresented in NLP resources: Ghana, Kenya, Nigeria, and South Africa. By utilizing socioculturally-situated, community-engaged methods, including telephonic surveys moderated in native
languages, we establish a reproducible methodology that is sensitive to the region's complex linguistic diversity and traditional orality. By deliberately balancing the sample across diverse ethnic and demographic backgrounds, we ensure broad coverage, resulting in a
dataset of 3,534 stereotypes in English and 3,206 stereotypes across 15 native
languages.
Read the full abstract ▾
All authors Aishwarya Verma, Laud Ammah, Olivia Nercy Ndlovu Lucas, Andrew Zaldivar, Vinodkumar Prabhakaran, Sunipa Dev
Computation and Language
Detecting Hate and Inflammatory Content in Bengali Memes: A New Multimodal Dataset and Co-Attention Framework
Rakib Ullah, Mominul islam, Md Sanjid Hossain et al. (+1 more)
Internet memes have become a dominant form of expression on social media, including within the Bengali speaking community. While often humorous, memes can also be exploited to spread offensive, harmful, and inflammatory content targeting individuals and groups. Detecting this type of content is exceptionally challenging due to its satirical, subtle, and culturally specific nature. This problem is magnified for low-resource
languages like Bengali, as existing research predominantly focuses on high-resource
languages. To address this critical research gap, we introduce Bn-HIB (Bangla Hate Inflammatory Benign), a novel
dataset containing 3,247 manually annotated Bengali memes categorized as Benign, Hate, or Inflammatory. Significantly, Bn- HIB is the first
dataset to distinguish inflammatory content from direct hate
speech in Bengali memes. Furthermore, we propose the MCFM (Multi-Modal Co-
Attention Fusion Model), a simple yet effective architecture that mutually analyses both the visual and textual elements of a meme. MCFM employs a co-
attention mechanism to identify and fuse the most critical features from each modality, leading to a more accurate classification. Our experiments show that MCFM significantly outperforms several state-of-the-art models on the Bn-HIB
dataset, demonstrating its effectiveness in this nuanced task. To facilitate reproducibility and future research, the Bn-HIB
dataset has been made publicly available through Mendeley Data. Warning: This work contains material that may be disturbing to some audience members. Viewer discretion is advised
Read the full abstract ▾
All authors Rakib Ullah, Mominul islam, Md Sanjid Hossain, Md Ismail Hossain
Computation and Language
Scaling In, Not Up? Testing Thick Citation Context Analysis with GPT-5 and Fragile Prompts
Arno Simons
This paper tests whether large
language models (LLMs) can support interpretative citation context analysis (CCA) by scaling in thick, text-grounded readings of a single hard case rather than scaling up typological labels. It foregrounds
prompt-sensitivity analysis as a methodological issue by varying
prompt scaffolding and framing in a balanced 2x3 design. Using footnote 6 in Chubin and Moitra (1975) and Gilbert's (1977) reconstruction as a probe, I implement a two-stage GPT-5 pipeline: a citation-text-only surface classification and expectation pass, followed by cross-document interpretative reconstruction using the citing and cited full texts. Across 90 reconstructions, the model produces 450 distinct hypotheses. Close reading and inductive coding identify 21 recurring interpretative moves, and linear probability models estimate how
prompt choices shift their frequencies and lexical repertoire. GPT-5's surface pass is highly stable, consistently classifying the citation as "supplementary". In reconstruction, the model generates a structured space of plausible alternatives, but scaffolding and examples redistribute
attention and vocabulary, sometimes toward strained readings. Relative to Gilbert, GPT-5 detects the same textual hinges yet more often resolves them as lineage and positioning than as admonishment. The study outlines opportunities and risks of using LLMs as guided co-analysts for inspectable, contestable interpretative CCA, and it shows that
prompt scaffolding and framing systematically tilt which plausible readings and vocabularies the model foregrounds.
Read the full abstract ▾
Computation and Language
Decoder-based Sense Knowledge Distillation
Qitong Wang, Mohammed J. Zaki, Georgios Kollias et al. (+1 more)
Large
language models (LLMs) learn contextual
embeddings that capture rich semantic information, yet they often overlook structured lexical knowledge such as word senses and relationships. Prior work has shown that incorporating sense dictionaries can improve knowledge
distillation for encoder models, but their application to decoder as generative models remains challenging. In this paper, we introduce Decoder-based Sense Knowledge
Distillation (DSKD), a framework that integrates lexical resources into the training of decoder-style LLMs without requiring dictionary lookup at inference time. Extensive experiments on diverse
benchmarks demonstrate that DSKD significantly enhances knowledge
distillation performance for decoders, enabling generative models to inherit structured semantics while maintaining efficient training.
Read the full abstract ▾
All authors Qitong Wang, Mohammed J. Zaki, Georgios Kollias, Vasileios Kalantzis
Computation and Language · Cross-listed from cs.MM
Decoding the Hook: A Multimodal LLM Framework for Analyzing the Hooking Period of Video Ads
Kunpeng Zhang, Poppy Zhang, Shawndra Hill et al. (+1 more)
Video-based ads are a vital medium for brands to engage consumers, with social media platforms leveraging user data to optimize ad delivery and boost engagement. A crucial but under-explored aspect is the 'hooking period', the first three seconds that capture viewer
attention and influence engagement metrics. Analyzing this brief window is challenging due to the
multimodal nature of
video content, which blends visual, auditory, and textual elements. Traditional methods often miss the nuanced interplay of these components, requiring advanced frameworks for thorough evaluation. This study presents a framework using
transformer-based
multimodal large
language models (MLLMs) to analyze the hooking period of
video ads. It tests two frame sampling strategies, uniform random sampling and key frame selection, to ensure balanced and representative acoustic feature extraction, capturing the full range of design elements. The hooking
video is processed by state-of-the-art MLLMs to generate descriptive analyses of the ad's initial impact, which are distilled into coherent topics using BERTopic for high-level abstraction. The framework also integrates features such as audio attributes and aggregated ad targeting information, enriching the feature set for further analysis. Empirical validation on large-scale real-world data from social media platforms demonstrates the efficacy of our framework, revealing correlations between hooking period features and key performance metrics like conversion per investment. The results highlight the practical applicability and predictive power of the approach, offering valuable insights for optimizing
video ad strategies. This study advances
video ad analysis by providing a scalable methodology for understanding and enhancing the initial moments of
video advertisements.
Read the full abstract ▾
All authors Kunpeng Zhang, Poppy Zhang, Shawndra Hill, Amel Awadelkarim
Computation and Language
Recovered in Translation: Efficient Pipeline for Automated Translation of Benchmarks and Datasets
Hanna Yukhymenko, Anton Alexandrov and Martin Vechev
The reliability of
multilingual Large
Language Model (LLM) evaluation is currently compromised by the inconsistent quality of translated
benchmarks. Existing resources often suffer from semantic drift and context loss, which can lead to misleading performance metrics. In this work, we present a fully automated framework designed to address these challenges by enabling scalable, high-quality translation of
datasets and
benchmarks. We demonstrate that adapting test-time compute scaling strategies, specifically Universal Self-Improvement (USI) and our proposed multi-round ranking method, T-RANK, allows for significantly higher quality outputs compared to traditional pipelines. Our framework ensures that
benchmarks preserve their original task structure and linguistic nuances during localization. We apply this approach to translate popular
benchmarks and
datasets into eight Eastern and Southern European
languages (Ukrainian, Bulgarian, Slovak, Romanian, Lithuanian, Estonian, Turkish, Greek). Evaluations using both reference-based metrics and LLM-as-a-judge show that our translations surpass existing resources, resulting in more accurate downstream model assessment. We release both the framework and the improved
benchmarks to facilitate robust and reproducible
multilingual AI development.
Read the full abstract ▾
Computation and Language
SumTablets: A Transliteration Dataset of Sumerian Tablets
Cole Simmons, Richard Diehl Martinez and Dan Jurafsky
Sumerian transliteration is a conventional system for representing a scholar's interpretation of a tablet in the Latin script. Thanks to visionary digital Assyriology projects such as ETCSL, CDLI, and Oracc, a large number of Sumerian transliterations have been published online, and these data are well-structured for a variety of search and analysis tasks. However, the absence of a comprehensive, accessible
dataset pairing transliterations with a digital representation of the tablet's cuneiform glyphs has prevented the application of modern Natural
Language Processing (NLP) methods to the task of Sumerian transliteration. To address this gap, we present SumTablets, a
dataset pairing Unicode representations of 91,606 Sumerian cuneiform tablets (totaling 6,970,407 glyphs) with the associated transliterations published by Oracc. We construct SumTablets by first preprocessing and standardizing the Oracc transliterations before mapping each reading back to the Unicode representation of the source glyph. Further, we retain parallel structural information (e.g., surfaces, newlines, broken segments) through the use of special
tokens. We release SumTablets as a Hugging Face
Dataset (CC BY 4.0) and open source data preparation code via GitHub. Additionally, we leverage SumTablets to implement and evaluate two transliteration baselines: (1) weighted sampling from a glyph's possible readings, and (2) fine-tuning an autoregressive
language model. Our fine-tuned
language model achieves an average transliteration character-level F-score (chrF) of 97.55, demonstrating the immediate potential of
transformer-based transliteration models in allowing experts to rapidly verify generated transliterations rather than manually transliterating tablets one-by-one.
Read the full abstract ▾
Computation and Language
Improving Parametric Knowledge Access in Reasoning Language Models
Melody Ma and John Hewitt
We study
reasoning for accessing world knowledge stored in a
language model's parameters. For example, recalling that Canberra is Australia's capital may benefit from thinking through major cities and the concept of purpose-built capitals. While
reasoning language models are trained via reinforcement learning to produce
reasoning traces on tasks such as mathematics, they may not reason well for accessing their own world knowledge. We first find that models do not generate their best world knowledge
reasoning by default: adding a simple "think step-by-step" cue demonstrates statistically significant improvement in knowledge recall but not math. Motivated by this, we propose training models to reason over their parametric knowledge using world-knowledge question answering as a verifiable reward. After reinforcement learning on TriviaQA (+9.9%), performance also improves on Natural Questions, HotpotQA, SimpleQA, and StrategyQA by 4.2%, 2.1%, 0.6%, and 3.0%, respectively.
Reasoning models are under-optimized for parametric knowledge access, but can be easily trained to reason better.
Read the full abstract ▾
Computation and Language · Cross-listed from cs.LG
GUI-Libra: Training Native GUI Agents to Reason and Act with Action-aware Supervision and Partially Verifiable RL
Rui Yang, Qianhui Wu, Zhaoyang Wang et al. (+8 more)
Open-source native GUI
agents still lag behind closed-source systems on long-horizon
navigation tasks. This gap stems from two limitations: a shortage of high-quality, action-aligned
reasoning data, and the direct adoption of generic post-training pipelines that overlook the unique challenges of GUI
agents. We identify two fundamental issues in these pipelines: (i) standard SFT with CoT
reasoning often hurts grounding, and (ii) step-wise RLVR-tyle training faces partial verifiability, where multiple actions can be correct but only a single demonstrated action is used for verification. This makes offline step-wise metrics weak predictors of online task success. In this work, we present GUI-Libra, a tailored training recipe that addresses these challenges. First, to mitigate the scarcity of action-aligned
reasoning data, we introduce a data construction and filtering pipeline and release a curated 81K GUI
reasoning dataset. Second, to reconcile
reasoning with grounding, we propose action-aware SFT that mixes
reasoning-then-action and direct-action data and reweights
tokens to emphasize action and grounding. Third, to stabilize RL under partial verifiability, we identify the overlooked importance of KL regularization in RLVR and show that a KL trust region is critical for improving offline-to-online predictability; we further introduce success-adaptive scaling to downweight unreliable negative gradients. Across diverse web and mobile
benchmarks, GUI-Libra consistently improves both step-wise accuracy and end-to-end task completion. Our results suggest that carefully designed post-training and data curation can unlock significantly stronger task-solving capabilities without costly online data collection. We release our
dataset, code, and models to facilitate further research on data-efficient post-training for
reasoning-capable GUI
agents.
Read the full abstract ▾
All authors Rui Yang, Qianhui Wu, Zhaoyang Wang, Hanyang Chen, Ke Yang, Hao Cheng, Huaxiu Yao, Baolin Peng, Huan Zhang, Jianfeng Gao, Tong Zhang
Computation and Language
LiCQA : A Lightweight Complex Question Answering System
Sourav Saha, Dwaipayan Roy and Mandar Mitra
Over the last twenty years, significant progress has been made in designing and implementing Question Answering (QA) systems. However, addressing complex questions, the answers to which are spread across multiple documents, remains a challenging problem. Recent QA systems that are designed to handle complex questions work either on the basis of knowledge graphs, or utilise contem- porary neural models that are expensive to train, in terms of both computational resources and the volume of training data required. In this paper, we present LiCQA, an unsupervised question answer- ing model that works primarily on the basis of corpus evidence. We empirically compare the effectiveness and efficiency of LiCQA with two recently presented QA systems, which are based on different underlying principles. The results of our experiments show that LiCQA significantly outperforms these two state-of-the-art systems on
benchmark data with noteworthy reduction in latency.
Read the full abstract ▾
Computation and Language
DySCO: Dynamic Attention-Scaling Decoding for Long-Context Language Models
Xi Ye, Wuwei Zhang, Fangcong Yin et al. (+2 more)
Understanding and
reasoning over long contexts is a crucial capability for
language models (LMs). Although recent models support increasingly long context windows, their accuracy often deteriorates as input length grows. In practice, models often struggle to keep
attention aligned with the most relevant context throughout decoding. In this work, we propose DYSCO, a novel decoding
algorithm for improving long-context
reasoning. DYSCO leverages
retrieval heads–a subset of
attention heads specialized for longcontext
retrieval–to identify task-relevant
tokens at each decoding step and explicitly up-weight them. By doing so, DYSCO dynamically adjusts
attention during generation to better utilize relevant context. The method is training-free and can be applied directly to any off-the-shelf LMs. Across multiple instruction-tuned and
reasoning models, DYSCO consistently improves performance on challenging long-context
reasoning benchmarks, yielding relative gains of up to 25% on MRCR and LongBenchV2 at 128K context length with modest additional compute. Further analysis highlights the importance of both dynamic
attention rescaling and retrievalhead guided selection for the effectiveness of the method, while providing interpretability insights into decoding-time
attention behavior. Our code is available at https://github.com/princeton-pli/DySCO.
Read the full abstract ▾
All authors Xi Ye, Wuwei Zhang, Fangcong Yin, Howard Yen, Danqi Chen
Computation and Language
Dynamic Personality Adaptation in Large Language Models via State Machines
Leon Pielage, Ole Hätscher, Mitja Back et al. (+2 more)
The inability of Large
Language Models (LLMs) to modulate their personality expression in response to evolving dialogue dynamics hinders their performance in complex, interactive contexts. We propose a model-agnostic framework for dynamic personality simulation that employs state machines to represent latent personality states, where transition probabilities are dynamically adapted to the conversational context. Part of our architecture is a modular pipeline for continuous personality scoring that evaluates dialogues along latent axes while remaining agnostic to the specific personality models, their dimensions, transition mechanisms, or LLMs used. These scores function as dynamic state variables that systematically reconfigure the system
prompt, steering behavioral
alignment throughout the interaction.We evaluate this framework by operationalizing the Interpersonal Circumplex (IPC) in a medical education setting. Results demonstrate that the system successfully adapts its personality state to user inputs, but also influences user behavior, thereby facilitating de-escalation training. Notably, the scoring pipeline maintains comparable precision even when utilizing lightweight, fine-tuned classifiers instead of large-scale LLMs. This work demonstrates the feasibility of modular, personality-adaptive architectures for education, customer support, and broader human-computer interaction.
Read the full abstract ▾
All authors Leon Pielage, Ole Hätscher, Mitja Back, Bernhard Marschall, Benjamin Risse
Computation and Language · Cross-listed from cs.HC
When AI Writes, Whose Voice Remains? Quantifying Cultural Marker Erasure Across World English Varieties in Large Language Models
Satyam Kumar Navneet, Joydeep Chandra and Yong Zhang
Large
Language Models (LLMs) are increasingly used to “professionalize” workplace communication, often at the cost of linguistic identity. We introduce "Cultural Ghosting", the systematic erasure of linguistic markers unique to non-native English varieties during text processing. Through analysis of 22,350 LLM outputs generated from 1,490 culturally marked texts (Indian, Singaporean,& Nigerian English) processed by five models under three
prompt conditions, we quantify this phenomenon using two novel metrics: Identity Erasure Rate (IER) & Semantic Preservation Score (SPS). Across all
prompts, we find an overall IER of 10.26%, with model-level variation from 3.5% to 20.5% (5.9x range). Crucially, we identify a Semantic Preservation Paradox: models maintain high semantic similarity (mean SPS = 0.748) while systematically erasing cultural markers. Pragmatic markers (politeness conventions) are 1.9x more vulnerable than lexical markers (71.5% vs. 37.1% erasure). Our experiments demonstrate that explicit cultural-preservation
prompts reduce erasure by 29% without sacrificing semantic quality.
Read the full abstract ▾
Computation and Language · Cross-listed from cs.CV
NoLan: Mitigating Object Hallucinations in Large Vision-Language Models via Dynamic Suppression of Language Priors
Lingfeng Ren, Weihao Yu, Runpeng Yu et al. (+1 more)
Object
hallucination is a critical issue in Large
Vision-
Language Models (LVLMs), where outputs include objects that do not appear in the input image. A natural question arises from this phenomenon: Which component of the LVLM pipeline primarily contributes to object
hallucinations? The
vision encoder to perceive visual information, or the
language decoder to generate text responses? In this work, we strive to answer this question through designing a systematic experiment to analyze the roles of the
vision encoder and the
language decoder in
hallucination generation. Our observations reveal that object
hallucinations are predominantly associated with the strong priors from the
language decoder. Based on this finding, we propose a simple and training-free framework, No-
Language-
Hallucination Decoding, NoLan, which refines the output distribution by dynamically suppressing
language priors, modulated based on the output distribution difference between
multimodal and text-only inputs. Experimental results demonstrate that NoLan effectively reduces object
hallucinations across various LVLMs on different tasks. For instance, NoLan achieves substantial improvements on POPE, enhancing the accuracy of LLaVA-1.5 7B and Qwen-VL 7B by up to 6.45 and 7.21, respectively. The code is publicly available at: https://github.com/lingfengren/NoLan.
Read the full abstract ▾
All authors Lingfeng Ren, Weihao Yu, Runpeng Yu, Xinchao Wang
Computation and Language
IndicIFEval: A Benchmark for Verifiable Instruction-Following Evaluation in 14 Indic Languages
Thanmay Jayakumar, Mohammed Safi Ur Rahman Khan, Raj Dabre et al. (+2 more)
Instruction-following
benchmarks remain predominantly English-centric, leaving a critical evaluation gap for the hundreds of millions of Indic
language speakers. We introduce IndicIFEval, a
benchmark evaluating constrained generation of LLMs across 14 Indic
languages using automatically verifiable, rule-based instructions. It comprises around 800 human-verified examples per
language spread across two complementary subsets: IndicIFEval-Ground, translated
prompts from IFEval (Zhou et al., 2023) carefully localized for Indic contexts, and IndicIFEval-Ground, synthetically generated instructions grounded in native Indic content. We conduct a comprehensive evaluation of major open-weight and proprietary models spanning both
reasoning and non-
reasoning models. While models maintain strong adherence to formatting constraints, they struggle significantly with lexical and cross-lingual tasks – and despite progress in high-resource
languages, instruction-following across the broader Indic family lags significantly behind English. We release IndicIFEval and its evaluation scripts to support progress on
multilingual constrained generation (http://github.com/ai4bharat/IndicIFEval).
Read the full abstract ▾
All authors Thanmay Jayakumar, Mohammed Safi Ur Rahman Khan, Raj Dabre, Ratish Puduppully, Anoop Kunchukuttan
Computation and Language · Cross-listed from cs.SE
SWE-Protégé: Learning to Selectively Collaborate With an Expert Unlocks Small Language Models as Software Engineering Agents
Patrick Tser Jern Kon, Archana Pradeep, Ang Chen et al. (+5 more)
Small
language models (SLMs) offer compelling advantages in cost, latency, and adaptability, but have so far lagged behind larger models on long-horizon software engineering tasks such as SWE-bench, where they suffer from pervasive action looping and low resolution rates. We introduce SWE-Protégé, a post-training framework that reframes software repair as an expert-protégé collaboration problem. In SWE-Protégé, an SLM remains the sole decision-maker while learning to selectively seek guidance from a strong expert model, recognize stalled states, and follow through on expert feedback. Our approach combines supervised fine-tuning on expert-augmented trajectories with agentic reinforcement learning that explicitly discourages degenerative looping and unproductive expert collaboration. We lightly post-train Qwen2.5-Coder-7B-Instruct to achieve 42.4% Pass@1 on SWE-bench Verified, a +25.4% improvement over the prior SLM state of the art, while using expert assistance sparsely (~4 calls per task and 11% of total
tokens).
Read the full abstract ▾
All authors Patrick Tser Jern Kon, Archana Pradeep, Ang Chen, Alexander P. Ellis, Warren Hunt, Zijian Wang, John Yang, Samuel Thompson
Computation and Language
Confidence-Driven Multi-Scale Model Selection for Cost-Efficient Inference
Bo-Wei Chen, Chung-Chi Chen and An-Zi Yen
Large
Language Models (LLMs) have revolutionized inference across diverse natural
language tasks, with larger models performing better but at higher computational costs. We propose a confidence-driven strategy that dynamically selects the most suitable model based on confidence estimates. By assessing a model's confidence in handling the task and response accuracy, tasks that are likely to be solved correctly are retained, while more uncertain or complex cases are delegated to a larger model, ensuring reliability while minimizing computation. Specifically, we evaluate a model's likelihood of knowing the correct answer and the probability that its response is accurate. Experiments on the Massive Multitask
Language Understanding (MMLU)
benchmark show that our approach achieves accuracy comparable to the largest model while reducing computational costs by 20% to 40%. When applied to GPT-4o API calls, it reduces
token usage by approximately 60%, further improving cost efficiency. These findings indicate the potential of confidence-based model selection to enhance real-world LLM deployment, particularly in resource-constrained settings such as edge devices and commercial API applications.
Read the full abstract ▾
Computation and Language
Understanding Artificial Theory of Mind: Perturbed Tasks and Reasoning in Large Language Models
Christian Nickel, Laura Schrewe, Florian Mai et al. (+1 more)
Theory of Mind (ToM) refers to an
agent's ability to model the internal states of others. Contributing to the debate whether large
language models (LLMs) exhibit genuine ToM capabilities, our study investigates their ToM robustness using perturbations on false-belief tasks and examines the potential of Chain-of-Thought prompting (CoT) to enhance performance and explain the LLM's decision. We introduce a handcrafted, richly annotated ToM
dataset, including classic and perturbed false belief tasks, the corresponding spaces of valid
reasoning chains for correct task completion, subsequent
reasoning faithfulness, task solutions, and propose metrics to evaluate
reasoning chain correctness and to what extent final answers are faithful to
reasoning traces of the generated CoT. We show a steep drop in ToM capabilities under task perturbation for all evaluated LLMs, questioning the notion of any robust form of ToM being present. While CoT prompting improves the ToM performance overall in a faithful manner, it surprisingly degrades accuracy for some perturbation classes, indicating that selective application is necessary.
Read the full abstract ▾
All authors Christian Nickel, Laura Schrewe, Florian Mai, Lucie Flek
Computation and Language
DLT-Corpus: A Large-Scale Text Collection for the Distributed Ledger Technology Domain
Walter Hernandez Cruz, Peter Devine, Nikhil Vadgama et al. (+2 more)
We introduce DLT-Corpus, the largest domain-specific text collection for Distributed Ledger Technology (DLT) research to date: 2.98 billion
tokens from 22.12 million documents spanning scientific literature (37,440 publications), United States Patent and Trademark Office (USPTO) patents (49,023 filings), and social media (22 million posts). Existing Natural
Language Processing (NLP) resources for DLT focus narrowly on cryptocurrency price prediction and smart contracts, leaving domain-specific
language underexplored despite the sector's ~$3 trillion
market capitalization and rapid technological
evolution. We demonstrate DLT-Corpus' utility by analyzing patterns of technology emergence and
market-innovation correlations. Findings reveal that technologies first appear in our scientific literature subset before reaching patents and social media, following traditional technology transfer patterns. While social media sentiment remains overwhelmingly bullish even during crypto winters, scientific and patent activity grows less tied to short-term sentiment, tracking overall
market expansion in a virtuous cycle in which research precedes and enables economic growth that, in turn, funds further innovation. We release the DLT-Corpus and companion artifacts: LedgerBERT (+23% over BERT-base on DLT-specific Named Entity Recognition (NER) task), a sentiment analysis
dataset of 23,301 crypto news headlines and descriptions, tools, and code.
Read the full abstract ▾
All authors Walter Hernandez Cruz, Peter Devine, Nikhil Vadgama, Paolo Tasca, Jiahua Xu