Weaker LLMs' Opinions Also Matter: Mixture of Opinions Enhances LLM's Mathematical Reasoning
Yanan Chen, Ali Pesaranghader, Tanmana Sadhu
TL;DR
The paper tackles the reliability gap in mathematical reasoning for small-to-medium open LLMs and proposes Mixture of Opinions (MoO), a post-training approach that augments a stronger main LLM with Chain-of-Thought reasoning and answers from weaker ancillary LLMs. MoO operates in three phases: data curation with external opinions, post-training the main model on this MoO data, and inference that leverages ancillary opinions for final answers. Experiments on GSM8K, AQuA-RAT, and MATH show MoO outperforms strong baselines such as ICL, SFT, and MoA across configurations, with ablations confirming the importance of CoT and ancillary diversity. The work demonstrates that diverse reasoning paths from weaker models can meaningfully enhance multi-step mathematical reasoning and offers a practical, model-agnostic post-training strategy for improving LLM reasoning.
Abstract
Recent advances in Large Language Models (LLMs) have raised interest in their formal reasoning capabilities, particularly in mathematics. While closed LLMs like GPT-4 perform well on mathematical benchmarks, e.g., GSM8K, it remains unclear whether small to medium-sized open LLMs can achieve similar performance, questioning their reliability. To close this gap, we propose a post-training approach leveraging a mixture of opinions (MoO) from weaker ancillary LLMs to enhance a (relatively) stronger LLM's reasoning. For that, each post-training sample is augmented with Chain-of-Thought (CoT) reasoning steps and answers from ancillary LLMs, enabling the main LLM to learn from diverse perspectives. We compare MoO with standard supervised fine-tuning (SFT), few-shot prompting, and the Mixture of Agents (MoA) method on mathematical reasoning benchmarks. Our results show that incorporating weaker LLMs' opinions improves mathematical reasoning by an average of 5%, highlighting the value of diverse perspectives in reasoning tasks.
