arXiv AI

Measuring Mechanistic Uncertainty in Large Language Models via Causal Robustness

The paper introduces mechanistic uncertainty, a measure of how stable a large language model’s internal mechanisms are when producing a response. It defines the causal robustness margin as the smallest internal intervention needed to change the output, and implements this using Jacobian Lens steering vectors. Experiments on three open‑source models and five QA datasets show that incorrect or uncertain answers have smaller margins, while correctly learned facts exhibit larger margins after training, indicating that causal robustness complements traditional output‑based uncertainty methods.

arXiv Computation and Language
Oct 12

Self-Aware Knowledge Probing: Evaluating Language Models' Relational Knowledge through Confidence Calibration

The paper introduces a framework for assessing how well language models (LMs) calibrate their confidence when answering relational knowledge questions. It evaluates three types of confidence—intrinsic, paraphrase consistency, and linguistic—across 21 causal and 8 masked LMs, finding that most models, especially masked ones, are overconfident. The study shows that confidence estimates that account for rephrasing inconsistencies and increasing answer options lead to better calibration.

By Christopher Kissling, Elena Merdjanovska, Alan Akbik
Hugging Face Trending Papers
Jul 14

The Illusion of Robustness: Aggregate Accuracy Hides Prediction Flips under Task-Irrelevant Context

As large language models (LLMs) grow more capable, they are increasingly deployed in context-rich settings where task inputs are often accompanied by long, partially irrelevant context. In a controlled setting, we find that state-of-the-art models often appear robust to task-irrelevant context at the aggregate level: prepending it to benchmark questions causes little change in overall accuracy.

arXiv AI
Aug 20

Different Facets of Verbalised Overconfidence: an Interpretability Study

The study examines how the large language model Qwen3-4B exhibits overconfidence across three expressions of uncertainty—verbal epistemic markers, abstention, and numeric confidence scores—using controlled reasoning scenarios that vary logical necessity and possibility. Findings confirm a pronounced overconfidence tendency, especially when numeric scores are requested, and reveal that certainty is generated by a broad coalition of shared features while uncertainty relies on a sparse set of dedicated features. By intervening on these uncertainty features, the researchers demonstrate causal evidence of the imbalance driving overconfidence and show that this intervention can mitigate overconfident errors across different settings, languages, and an out‑of‑distribution modality task.

By Davide Mazzaccara, Leonardo Bertolazzi, Raffaella Bernardi
arXiv AI
Oct 2

Verbalized and Internal Probabilities Are Coupled in Large Language Models

The paper investigates the relationship between a large language model’s internal probability distribution and its verbalized confidence statements. By systematically manipulating training and in‑context data, the authors show that both internal and verbalized probabilities are influenced by distributional and asserted uncertainty in the data. They find that verbalized probabilities align with internal ones beyond what would be expected if they tracked the same sources independently, indicating that verbalized confidence can serve as a probe of the model’s internal distribution.

By Sinead Williamson, Jiaxuan Li, Nick Foti, Russ Webb, Masha Fedzechkina
arXiv Computation and Language
Aug 27

From Passive Response to Proactive Correction: Enhancing LLM Robustness Against Input Fact Perturbations

The paper introduces DEDUCE, a three‑stage framework that turns large language models into proactive error correctors by detecting input fact errors, devising correction strategies, and delivering reliable answers. It also presents MisFactQA, a dataset of factual errors, and new metrics for robustness evaluation. Experiments on TruthfulQA, FalseQA, and MisFactQA show significant gains in accuracy and error correction across Qwen, LLaMA, and Gemma models.

By Ping Wang, Xiangguo Sun, Bingbing Xu, Guocong Li, Xiaofeng Meng
Hugging Face Trending Papers
Jun 22

The Origins of Stochasticity: Comprehensive Investigations on Uncertainty Quantification for Large Language Models

Recent advancements in Large Language Models (LLMs) have enabled sophisticated reasoning and content generation, yet their inherent stochasticity poses significant challenges for ensuring predictive credibility. While traditional uncertainty taxonomy paradigms, such as the dichotomy of aleatoric and epistemic uncertainties, provide conceptual foundations, they often fail to capture the multi-component and multi-stage nature of LLM generation and struggle to evaluate the effectiveness of various Uncertainty Quantification (UQ) methods.

arXiv AI
Jul 23

Rethinking Uncertainty Evaluation in Large Language Models

arXiv:2607. 19367v1 Announce Type: new Abstract: Calibration is the primary criterion for evaluating LLM confidence, but it is insufficient: it admits trivially incoherent estimators, depends on the evaluation distribution, and does not test the extent to which the estimation can be interpreted as a consistent, underlying probability function.

By Krish Matta, Atharv Naphade, Andy Zou