arXiv AI
Sep 30

Beyond Symmetric Agents: Cognitive Diversity and Multi-Agent Debate in Small Language Models

The study evaluates multi‑agent debate (MAD) in small language models, testing whether cognitive diversity—via personas, sampling temperature, or model identity—drives performance gains. Across 23 models, five tasks, and over 5,500 runs, MAD consistently outperforms single‑model inference but, when matched for generation budget, it ties or falls behind self‑consistency sampling, with persona prompting actually reducing accuracy. The authors find that MAD’s benefits largely stem from the first answer exchange and that many reported gains are due to ensemble‑sampling effects rather than true diversity, highlighting the need for budget‑matched, contamination‑checked baselines. whyItMatters":"The findings clarify that MAD’s perceived advantages may be overestimated and that future debate mechanisms must be evaluated against rigorous, budget‑matched baselines to ensure genuine performance improvements."

By Leonardo Ferreira, Gardenia Liu, Kaden Zheng
arXiv Computation and Language
Oct 5

Silent Dissent: LLM Agents That Yield to the Majority Still Represent Their Original Premise

The paper investigates whether large language model (LLM) agents that yield to a unanimous majority in multi‑agent debate truly change their underlying premise or merely adjust their statement. Using two‑hop factual questions with an unstated intermediate entity, the authors show that agents that concede still encode the original bridge in their internal representations, as revealed by a Jacobian‑lens analysis, even when the majority answer is wrong. Experiments across several open‑weight models demonstrate that hiding or removing the agent’s earlier answer increases conformity and that the original premise can be recovered from the question alone.

By Ziang Ni, Peng Zou
arXiv AI
Sep 7

MABPD: Multi-Agent Bias Probing & Detection via Structured Argument Debate

MABPD (Multi‑Agent Bias Probing & Detection) is a training‑free pipeline that uses three specialized large language model agents to analyze news articles from complementary perspectives and resolve disagreements via a Structured Argument Debate (SAD) protocol. SAD imposes an asymmetric burden of proof—biased claims lacking grounded textual evidence receive zero weight—along with role‑weighted voting and post‑consensus verification, replacing task‑specific supervised decision boundaries. Ablation studies show that the debate module alone accounts for up to a 10.6‑point F1 gain, and on the BABE benchmark MABPD attains 83.4% macro F1, within 0.7 percentage points of the supervised state‑of‑the‑art, while achieving 75.0% zero‑shot accuracy on the SemEval 2019 HyperPartisan corpus.

By Garvit Joshi (Graphic Era University, Dehradun, India), Stavya Dhyani (Graphic Era University, Dehradun, India), Jasmine (Graphic Era University, Dehradun, India), Arun Chauhan (Graphic Era University, Dehradun, India)