Math RL has almost no intermediate supervision, so hierarchical hints lifted a 7B model from 30.4 to 39.1 percent on a new benchmark
AspireAI community · arXiv (cs.LG)
Reinforcement learning with verifiable rewards gives a final answer but almost no signal for the middle of a multi-step problem. Hierarchical Hint-based Reward uses the intrinsic sub-question structure of mathematical problems as intermediate conditioning signals during RLVR training, which are logically grounded milestones rather than chain-of-thought prompts, and shrinks the reasoning horizon toward the final answer. On the new HiMath benchmark, hierarchical hints alone lifted Qwen2.5-Math-7B from 30.4 to 39.1 percent accuracy, and up to 45.6 percent with oracle hierarchical hints, across diverse models and even without task-specific training.
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