← 研踪 PaperTrailACL Anthology · ACL 2026:acl:2026.acl-long.1921 · 记录 #1
From \log \pi to \pi: Taming Divergence in Soft Clipping via Bilateral Decoupled Decay of Probability Gradient Weight
来源日期（仅到月份） 2026-07
来源记录日期 2026-07
雷达观测 2026-11-01 21:48
摘要
Reinforcement Learning with Verifiable Rewards (RLVR) has catalyzed a leap in Large Language Model (LLM) reasoning, yet its optimization dynamics remain fragile. Standard algorithms like GRPO enforce stability via “hard clipping”, which inadvertently stifles exploration by discarding gradients of tokens outside the trust region. While recent “soft clipping” methods attempt to recover these gradients, they suffer from a critical challenge: relying on log-probability gradient (\nabla_\theta\log \pi_\theta) yields divergent weights as probabilities vanish, destabilizing LLM training. We rethink this convention by establishing probability gradient (\nabla_\theta \pi_\theta) as the superior optimization primitive. Accordingly, we propose Decoupled Gradient Policy Optimization (DGPO), which employs a decoupled decay mechanism based on importance sampling ratios. By applying asymmetric, continuous decay to boundary tokens, DGPO resolves the conflict between stability and sustained exploration. Extensive experiments across DeepSeek-R1-Distill-Qwen series models (1.5B/7B/14B) demonstrate that DGPO consistently outperforms strong baselines on various mathematical benchmarks, offering a robust and scalable solution for RLVR. Our code and implementation are available at: https://github.com/FlyTune/DGPO-RL.
论文发现出处
这些页面提供论文线索，不代表同行评审或质量认证。
观测到的版本
平台记录号代表本站观测到的元数据变化，不是作者修订号。来源日期仅到月份或年份时，按该月或该年首日存档。
记录 #1 · 2026-07 · 最新观测版本
From \log \pi to \pi: Taming Divergence in Soft Clipping via Bilateral Decoupled Decay of Probability Gradient Weight
Reinforcement Learning with Verifiable Rewards (RLVR) has catalyzed a leap in Large Language Model (LLM) reasoning, yet its optimization dynamics remain fragile. Standard algorithms like GRPO enforce stability via “hard clipping”, which inadvertently stifles exploration by discarding gradients of tokens outside the trust region. While recent “soft clipping” methods attempt to recover these gradients, they suffer from a critical challenge: relying on log-probability gradient (\nabla_\theta\log \pi_\theta) yields divergent weights as probabilities vanish, destabilizing LLM training. We rethink this convention by establishing probability gradient (\nabla_\theta \pi_\theta) as the superior optimization primitive. Accordingly, we propose Decoupled Gradient Policy Optimization (DGPO), which employs a decoupled decay mechanism based on importance sampling ratios. By applying asymmetric, continuous decay to boundary tokens, DGPO resolves the conflict between stability and sustained exploration. Extensive experiments across DeepSeek-R1-Distill-Qwen series models (1.5B/7B/14B) demonstrate that DGPO consistently outperforms strong baselines on various mathematical benchmarks, offering a robust and scalable solution for RLVR. Our code and implementation are available at: https://github.com/FlyTune/DGPO-RL.
查看此版本解读 →查看此版本原文 ↗