A new arXiv paper introduces the first systematic evaluation of data referencing errors (DREs) — incorrect citation or omission of table values — across LLMs ranging from 1.7B to 20B parameters. The authors find DREs are pervasive across all tested models and tasks, compromising intermediate reasoning steps beyond just final-answer accuracy. They demonstrate that a critic-based filtering and rejection sampling approach improves answer accuracy by up to 12%, and train a lightweight 4B critic model achieving 78.2% F1 on detecting DREs both in- and out-of-distribution.
A new arXiv paper argues that standard LLM benchmarks overstate model capabilities by focusing on average performance on training-data-adjacent tasks while ignoring response variance and error magnitude. The authors introduce a novel benchmark requiring frontier LLMs to write code for data analysis tasks, comparing results against human expert submissions. Human experts outperformed the frontier LLM on average across multiple metrics and showed lower performance variability. The findings challenge the prevailing narrative that LLMs perform at human-expert level on knowledge economy tasks.
A new arXiv paper evaluates 8 state-of-the-art LLMs on discrete probability problems using two datasets: standard exercises (average accuracy 0.96) and counterintuitive exercises designed to trigger heuristic reasoning (average accuracy 0.59). The authors document token bias causing 20%+ performance drops when canonical problem formulations are disguised, and up to 34% degradation when misleading suggestions are embedded in prompts. The findings argue that current LLMs are not genuine probabilistic reasoners despite their success on advanced math benchmarks.
A new arXiv paper introduces a taxonomy of factual error types in human-written text, derived from analysis of newspaper article corrections, identifying categories like kanji misconversions and numeral classifier errors absent from existing hallucination benchmarks. The authors evaluate several LLMs on Factual Error Detection (FED) tasks using both synthetic and real correction data. Even high-performance models like GPT-5.4 achieve only ~52% word-level F1 on synthetic data, underscoring the difficulty of detecting human-induced factual errors versus LLM hallucinations. The work highlights a neglected subproblem in factual accuracy research as the field has shifted focus toward LLM-generated hallucinations.
Researchers introduce RECOM, a contamination-free evaluation dataset of 15,000 r/AskReddit questions paired with authentic community replies postdating all evaluated models' training cutoffs. Testing five open-source 7–10B LLMs, the paper finds that no standard automatic metric (cosine similarity, BERTScore, LLM judges) simultaneously achieves both validity (distinguishing real from random answers) and discriminative power (ranking models against each other). Cosine similarity is valid but cannot rank models; BERTScore's apparent ranking collapses when response length is controlled. The authors argue this tradeoff is a structural property of metric representation design and recommend reporting metrics on both axes with an explicit random-baseline floor.
A new arXiv preprint tests the implicit assumption that LLM evaluation is easier than generation, using a controlled in-context QA setup across four benchmarks (SQuAD 2.0, DROP, HotpotQA, MuSiQue) and two models. Results show generation accuracy exceeds self-evaluation accuracy on three of four benchmarks, with attention analysis revealing that evaluation attends to context 3–5x less than generation does. LoRA fine-tuning experiments confirm the asymmetry is not a training artifact, with cross-task interference observed in both directions. The findings directly challenge assumptions underlying LLM-as-a-Judge and self-evaluation pipelines widely used in RLHF and agentic systems.
A preprint from arXiv demonstrates that an LLM pipeline can automate reproducibility assessments of published social and behavioral science studies, recovering original effect sizes in 41% of cases (vs. 34% for human reanalysts) and reaching the same qualitative conclusion in 96% of cases (vs. 74% for humans). The study evaluated 76 published studies with predefined claims. The results suggest LLMs could serve as a scalable tool for systematic auditing of empirical research, addressing the resource-intensive nature of traditional reproducibility efforts.
A new arXiv paper evaluates whether LLMs can recognize that their own prior responses were elicited by adversarial prefill attacks, testing ten open-weight models (3B–70B) across four safety benchmarks. Models claim intent on prefilled responses only 27.3% of the time on average, and introspective signal is largely mediated by refusal-related reasoning. Three LoRA fine-tuning methods (SFT, GRPO, DPO) improve the intention-probe gap but counterintuitively raise attack success rates on most models, suggesting partial and fragile mitigation. The findings raise concerns about the reliability of LLM self-reports in safety-critical contexts.
This paper systematically investigates strategies for extending LLM-based automatic evaluation (LLMs-as-a-Judge) to multilingual settings, covering high-, mid-, and low-resource languages (English, Spanish, Basque). The authors compare instruction translation, monolingual vs. multilingual supervision, and model size, finding that fine-tuned smaller models can match proprietary models when in-domain data is available, while zero-shot larger models are preferable out-of-domain. Two meta-evaluation datasets are extended to Spanish and Basque, and all data and code are publicly released.