Learning from Own Solutions: Self-Conditioned Credit Assignment for Reinforcement Learning with Verifiable Rewards
Summary
SC-GRPO (Self-Conditioned GRPO) is a novel method addressing limitations in reinforcement learning with verifiable rewards (RLVR) for large language models (LLMs) on reasoning tasks. Traditional methods like GRPO assign uniform credit across tokens, inefficiently distributing gradients, while existing token-level credit assignment often requires external resources such as process reward models or ground-truth answers. SC-GRPO leverages the observation that conditioning a model on its own verified trajectories creates a measurable per-token KL divergence between original and conditioned distributions. This KL divergence is then applied as a multiplicative weight on GRPO gradients. Across five benchmarks spanning math, code, and agentic tasks, SC-GRPO consistently outperforms GRPO by 8.1%, DAPO by 5.9%, and also achieves higher performance than OPD, demonstrating stronger out-of-distribution capabilities.
Key takeaway
For AI scientists and machine learning engineers developing LLMs for complex reasoning, SC-GRPO offers a significant advancement in credit assignment. By leveraging self-conditioned KL divergence to weight GRPO gradients, you can achieve more precise learning without relying on expensive external supervision. Consider integrating SC-GRPO to improve your models' performance on math, code, and agentic tasks, especially when out-of-distribution robustness is critical. This approach enhances training efficiency and reasoning accuracy.
Key insights
SC-GRPO improves LLM reasoning by using self-conditioned KL divergence for fine-grained credit assignment in RLVR.
Principles
- Uniform credit assignment in RLVR wastes gradient on routine tokens.
- Conditioning a model on its own verified trajectories induces measurable per-token KL divergence.
- Distilling from a self-teacher with multiple verified trajectories leads to infeasible solutions.
Method
SC-GRPO uses per-token KL divergence, derived from self-conditioned verified trajectories, as a multiplicative weight on GRPO gradients to refine credit assignment.
In practice
- Apply SC-GRPO to enhance LLM performance on math and code reasoning.
- Improve out-of-distribution generalization for agentic tasks.
Topics
- Reinforcement Learning
- Large Language Models
- Credit Assignment
- KL Divergence
- SC-GRPO
- Reasoning Tasks
Best for: Research Scientist, AI Scientist, Machine Learning Engineer, NLP Engineer
Related on AIssential
Editorial summary, takeaway, and curation by AIssential. Original article published by Takara TLDR - Daily AI Papers.