Enhancing Multi-Agent Debate System Performance via Confidence Expression

Zijie Lin, Bryan Hooi


Abstract
Generative Large Language Models (LLMs) have demonstrated remarkable performance across a wide range of tasks. Recent research has introduced Multi-Agent Debate (MAD) systems, which leverage multiple LLMs to simulate human debate and thereby improve task performance. However, while some LLMs may possess superior knowledge or reasoning capabilities for specific tasks, they often struggle to clearly communicate this advantage during debates, in part due to a lack of confidence expression. Moreover, inappropriate confidence expression can cause agents in MAD systems to either stubbornly maintain incorrect beliefs or converge prematurely on suboptimal answers, ultimately reducing debate effectiveness and overall system performance. To address these challenges, we propose incorporating confidence expression into MAD systems to allow LLMs to explicitly communicate their confidence levels. To validate this approach, we develop ConfMAD, a MAD framework that integrates confidence expression throughout the debate process. Experimental results demonstrate the effectiveness of our method, and we further analyze how confidence influences debate dynamics, offering insights into the design of confidence-aware MAD systems.
Anthology ID:
2025.findings-emnlp.343
Volume:
Findings of the Association for Computational Linguistics: EMNLP 2025
Month:
November
Year:
2025
Address:
Suzhou, China
Editors:
Christos Christodoulopoulos, Tanmoy Chakraborty, Carolyn Rose, Violet Peng
Venue:
Findings
SIG:
Publisher:
Association for Computational Linguistics
Note:
Pages:
6453–6471
Language:
URL:
https://preview.aclanthology.org/name-variant-enfa-fane/2025.findings-emnlp.343/
DOI:
10.18653/v1/2025.findings-emnlp.343
Bibkey:
Cite (ACL):
Zijie Lin and Bryan Hooi. 2025. Enhancing Multi-Agent Debate System Performance via Confidence Expression. In Findings of the Association for Computational Linguistics: EMNLP 2025, pages 6453–6471, Suzhou, China. Association for Computational Linguistics.
Cite (Informal):
Enhancing Multi-Agent Debate System Performance via Confidence Expression (Lin & Hooi, Findings 2025)
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PDF:
https://preview.aclanthology.org/name-variant-enfa-fane/2025.findings-emnlp.343.pdf
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