arXiv AI By Jihao Huang, Guangjia Chai, Zhirui Chen, Lei Wang, Yao Liu, Liu Qi, Pengjie Ding, Xinyang Liu, Chengxun Jia, Ling Shao, Hongyu Chen, Junchen Wan

MGE-PO: Entropy-Aware Credit Assignment for Mathematical Reasoning

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MGE-PO introduces an entropy-aware credit assignment framework for mathematical reasoning, using a four-quadrant advantage shaping that blends verified correctness with rollout generation entropy. The method assigns larger bonuses to low-entropy successful responses and larger penalties to high-entropy failures, guided by an online entropy-based question curriculum. Experiments on Qwen3-8B-Base and Qwen2.5-7B-Base show significant macro average and pass rate improvements across multiple benchmarks.

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