Rewarding Doubt: A Reinforcement Learning Approach to Calibrated Confidence Expression of Large Language Models

Fuente: arXiv
Gespeichert in:
Bibliographische Detailangaben
Hauptverfasser: Bani-Harouni, David, Pellegrini, Chantal, Stangel, Paul, Özsoy, Ege, Zaripova, Kamilia, Navab, Nassir, Keicher, Matthias
Format: Preprint
Veröffentlicht: 2025
Schlagworte:
Online-Zugang:
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
_version_ 1866914359665491968
author Bani-Harouni, David
Pellegrini, Chantal
Stangel, Paul
Özsoy, Ege
Zaripova, Kamilia
Navab, Nassir
Keicher, Matthias
author_facet Bani-Harouni, David
Pellegrini, Chantal
Stangel, Paul
Özsoy, Ege
Zaripova, Kamilia
Navab, Nassir
Keicher, Matthias
contents A safe and trustworthy use of Large Language Models (LLMs) requires an accurate expression of confidence in their answers. We propose a novel Reinforcement Learning approach that allows to directly fine-tune LLMs to express calibrated confidence estimates alongside their answers to factual questions. Our method optimizes a reward based on the logarithmic scoring rule, explicitly penalizing both over- and under-confidence. This encourages the model to align its confidence estimates with the actual predictive accuracy. The optimal policy under our reward design would result in perfectly calibrated confidence expressions. Unlike prior approaches that decouple confidence estimation from response generation, our method integrates confidence calibration seamlessly into the generative process of the LLM. Empirically, we demonstrate that models trained with our approach exhibit substantially improved calibration and generalize to unseen tasks without further fine-tuning, suggesting the emergence of general confidence awareness.
format Preprint
id arxiv_https___arxiv_org_abs_2503_02623
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Rewarding Doubt: A Reinforcement Learning Approach to Calibrated Confidence Expression of Large Language Models
Bani-Harouni, David
Pellegrini, Chantal
Stangel, Paul
Özsoy, Ege
Zaripova, Kamilia
Navab, Nassir
Keicher, Matthias
Computation and Language
Artificial Intelligence
A safe and trustworthy use of Large Language Models (LLMs) requires an accurate expression of confidence in their answers. We propose a novel Reinforcement Learning approach that allows to directly fine-tune LLMs to express calibrated confidence estimates alongside their answers to factual questions. Our method optimizes a reward based on the logarithmic scoring rule, explicitly penalizing both over- and under-confidence. This encourages the model to align its confidence estimates with the actual predictive accuracy. The optimal policy under our reward design would result in perfectly calibrated confidence expressions. Unlike prior approaches that decouple confidence estimation from response generation, our method integrates confidence calibration seamlessly into the generative process of the LLM. Empirically, we demonstrate that models trained with our approach exhibit substantially improved calibration and generalize to unseen tasks without further fine-tuning, suggesting the emergence of general confidence awareness.
title Rewarding Doubt: A Reinforcement Learning Approach to Calibrated Confidence Expression of Large Language Models
topic Computation and Language
Artificial Intelligence
url https://arxiv.org/abs/2503.02623