Enregistré dans:
Détails bibliographiques
Auteurs principaux: Zhao, Tianyi, He, Yinhan, Zheng, Wendy, Zhang, Yujie, Chen, Chen
Format: Preprint
Publié: 2026
Sujets:
Accès en ligne:https://arxiv.org/abs/2604.01457
Tags: Ajouter un tag
Pas de tags, Soyez le premier à ajouter un tag!
_version_ 1866914439269187584
author Zhao, Tianyi
He, Yinhan
Zheng, Wendy
Zhang, Yujie
Chen, Chen
author_facet Zhao, Tianyi
He, Yinhan
Zheng, Wendy
Zhang, Yujie
Chen, Chen
contents Large language models are often not just wrong, but \emph{confidently wrong}: when they produce factually incorrect answers, they tend to verbalize overly high confidence rather than signal uncertainty. Such verbalized overconfidence can mislead users and weaken confidence scores as a reliable uncertainty signal, yet its internal mechanisms remain poorly understood. We present a circuit-level mechanistic analysis of this inflated verbalized confidence in LLMs, organized around three axes: capturing verbalized confidence as a differentiable internal signal, identifying the circuits that causally inflate it, and leveraging these insights for targeted inference-time recalibration. Across two instruction-tuned LLMs on three datasets, we find that a compact set of MLP blocks and attention heads, concentrated in middle-to-late layers, consistently writes the confidence-inflation signal at the final token position. We further show that targeted inference-time interventions on these circuits substantially improve calibration. Together, our results suggest that verbalized overconfidence in LLMs is driven by identifiable internal circuits and can be mitigated through targeted intervention.
format Preprint
id arxiv_https___arxiv_org_abs_2604_01457
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle Wired for Overconfidence: A Mechanistic Perspective on Inflated Verbalized Confidence in LLMs
Zhao, Tianyi
He, Yinhan
Zheng, Wendy
Zhang, Yujie
Chen, Chen
Computation and Language
Large language models are often not just wrong, but \emph{confidently wrong}: when they produce factually incorrect answers, they tend to verbalize overly high confidence rather than signal uncertainty. Such verbalized overconfidence can mislead users and weaken confidence scores as a reliable uncertainty signal, yet its internal mechanisms remain poorly understood. We present a circuit-level mechanistic analysis of this inflated verbalized confidence in LLMs, organized around three axes: capturing verbalized confidence as a differentiable internal signal, identifying the circuits that causally inflate it, and leveraging these insights for targeted inference-time recalibration. Across two instruction-tuned LLMs on three datasets, we find that a compact set of MLP blocks and attention heads, concentrated in middle-to-late layers, consistently writes the confidence-inflation signal at the final token position. We further show that targeted inference-time interventions on these circuits substantially improve calibration. Together, our results suggest that verbalized overconfidence in LLMs is driven by identifiable internal circuits and can be mitigated through targeted intervention.
title Wired for Overconfidence: A Mechanistic Perspective on Inflated Verbalized Confidence in LLMs
topic Computation and Language
url https://arxiv.org/abs/2604.01457