Large language models

Model releases, architecture work and prompting research on large language models — from frontier-lab announcements to the arXiv papers behind them.

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arXiv AI
Sep 23

Testing, not presuming, adequacy: calibrating generative social simulators against emergent network structure

The paper introduces an adequacy‑aware calibration protocol for generative social simulators that integrates amortized posterior estimation, synthetic identifiability assessment, matched‑sample‑size adequacy checks, diagnosis‑guided repair, and held‑out audits. Applied to a second‑hand luxury resale market, the protocol reveals that behavioural parameters are recoverable but calibration is approximate and overconfident for one parameter, and that the simulator’s reachability reference is violated in every cell, particularly in mean purchased tier. The repair improves two of four cells but fails to restore full adequacy, and a held‑out audit uncovers a buyer‑breadth‑dispersion miss not detected earlier; profile‑source ablation shows language‑model‑derived persona profiles outperform a flat rule baseline, though within‑category brand relabelling has no consistent effect. whyItMatters":"The study demonstrates that without an adequacy check, generative social models may appear valid descriptively yet fail to capture key emergent network structures, highlighting the need for rigorous calibration protocols in social simulation research."

By Tengfei Shao, Chao Li, Xu Wang, Masayuki Goto
arXiv AI
Sep 23

Taming CoT Obfuscation in VLMs: From Mechanistic Evidence to Activation Enforcement

The paper investigates how reinforcement learning can unintentionally obscure the chain‑of‑thought (CoT) reasoning in vision‑language models, making their internal reasoning less traceable. By analyzing activation patterns, the authors show that template‑associated activations become less distinguishable during RL and that targeted interventions can mitigate this effect. They introduce TAME, a method that uses sparse autoencoders to suppress these problematic activations while still encouraging accurate behavior, achieving significant gains in CoT monitorability across multiple datasets and model families.

By Xutao Mao, Jianing Zhu, Jinman Zhao, Tongliang Liu, Xiaowen Chu, Cong Wang, Bo Han
arXiv AI
Sep 23

When the Agent Becomes the Kernel: A Systematization of Security on the Path to AI-Native Operating Systems

The paper discusses how large language model agents now act as privileged principals with kernel‑grade authority, yet lack the trusted mediation traditionally required for operating‑system security. It introduces a taxonomy that distinguishes between provenance‑based deterministic checks and content‑semantic checks, identifying a central mediation gap in distinguishing data from instruction and authorized from unauthorized actions. The authors argue that this gap creates an irreducible risk of undetected attacks whenever inputs and actions are not pre‑enumerated, and they propose defenses across runtime monitoring, architectural separation, and authorization while critiquing current evaluation practices. They extend the analysis to AI‑native operating systems where the model itself serves as the arbitration core, outlining design constraints, challenges, and a research agenda.

By Li Zhang, Yang Sun, Jie Shi
arXiv Machine Learning
Sep 23

The Probabilistic Structure of Large Language Models

The paper offers a unified probabilistic framework for large language models, describing them as probability measures over token sequences defined by autoregressive conditional distributions. Training is cast as maximum‑likelihood estimation solved via stochastic gradient methods, while generation is treated as sequential simulation of the resulting stochastic process. It also explores how the asymmetry of the Kullback–Leibler divergence relates to hallucination and the distinction between plausibility and truth, and extends the perspective to diffusion models that generate data by simulating a reverse‑time stochastic process.

By Adnan Aboulala\^a
arXiv Machine Learning
Sep 23

Same Quantity, Different Answer: Numerical Representation Invariance in Language Models

The paper introduces a benchmark of 3,600 exact‑rational word problems and 8,600 prompts that test whether language models give the same canonical answer when the same quantity is expressed in different numeric forms (decimal, fraction, percentage, number word, scientific notation, or unit‑converted). After normalizing answer syntax, canonical accuracy is high (0.969–0.996), but correctness across equivalent representations drops to 0.848–0.981, revealing that many errors stem from the evaluator’s number grammar rather than the models’ reasoning. The study also finds that representation consensus does not outperform paraphrase consensus on low‑error subsets and that certain models (e.g., Mistral Small 4) exhibit systematic unit‑conversion errors.

By Ephraim Atta-Duncan
arXiv Machine Learning
Sep 23

WeightBridge: An Efficient Weight Transfer Library for Reinforcement Learning

WeightBridge is a lightweight library that streamlines weight transfer between trainers and rollout generators in reinforcement learning systems, particularly for large language models. It automatically maps trainer and rollout weight layouts, then performs redundancy‑free, load‑balanced transfers while supporting various synchronization modes. Experiments show that WeightBridge can cut GPU stall time by up to 42× compared to leading open‑source RL frameworks, and it was easily integrated into two different frameworks by a coding agent.

By Xuanlin Jiang, Samuel Hsia, Michael Kuchnik, Zachary DeVito, Minlan Yu, Carole-Jean Wu
arXiv Computation and Language
Sep 23

LLM-Driven Training-free Location-Attribute Synergic Fusion: A Closed-Loop Paradigm for Dual-source Encrypted POIs and LULC Mapping

The paper introduces a novel, training‑free, LLM‑driven closed‑loop framework for fusing dual‑source encrypted points of interest (DSEP) to improve land‑use/land‑cover (LULC) mapping. By iteratively refining location transformations and attribute correspondences—using LLM‑based matching, particle swarm optimization, and fuzzy attribute reassessment—the method reduces matching complexity from O(N²) to O(N) and converges in about two iterations. Experiments across 31 Chinese provincial capitals demonstrate a 4.58 m average location residual and 95.12 % attribute accuracy, outperforming existing baselines by 1.77 m and 14.87 % respectively, and enabling georeferencing of encrypted vector data to WGS‑84 without ground control points.

By Chang Li, Xingtao Peng, Yongjun Zhang, Yinfei He, Cairun Huang
arXiv Computation and Language
Sep 23

SpecialEduBench: Benchmarking Vision-Language Models on Knowledge, Skill, and Attitude in Language Intervention for Autistic Children

SpecialEduBench is a new benchmark for vision‑language models that evaluates their pedagogical competence in language intervention for autistic children across knowledge, skill, and attitude dimensions. It contains 4,537 knowledge items, 200 skill items, and 68 attitude items derived from recorded interventions, with 192 response cells for attitude items that combine pressure and monitoring. Eight leading vision‑language models were tested, none achieving full performance, especially in honesty cells, indicating that current models still struggle with situated teaching tasks.

By Jihoi Na, Taeyeong Kim, Sungjune Kong, Jaemin Jung, Min Joung Park, Kyungtae Joo, Ahhyun Kim, Shim Jaechang, Sooyoung Joo, Dongjin Ka, SeJoong Kim, Jimin Kim, HyunJin Jung, Unggi Lee
arXiv Computation and Language
Sep 23

Faithful Autoformalization via Roundtrip Verification and Repair

The paper introduces a roundtrip verification method for ensuring that large language models (LLMs) produce faithful formalizations of natural language statements. By formalizing a statement, translating it back to natural language, re-formalizing, and checking logical equivalence with a formal tool, the approach detects inconsistencies without needing ground-truth annotations. When inconsistencies are found, a diagnosis localizes the error to a specific translation step, and a scoped repair operator attempts to correct it. The framework is evaluated on the Texas Transportation Code and Texas Parks and Wildlife Code using Claude Opus and GPT-5, showing that diagnosis-guided scoped repair is most effective and that rules failing the equivalence check exhibit significantly more natural language inference drift.

By Daneshvar Amrollahi, Jerry Lopez, Clark Barrett