arXiv:2606.05888cs.AI2026-06被引 2

提出连续动作空间的重试梯度方法,让智能体自发探索且不依赖额外奖励。

Retry Policy Gradients in Continuous Action Spaces

论文配图:Retry Policy Gradients in Continuous Action Spaces
图 1 · 摘自论文原文
  • 用路径导数估计器扩展重试目标到连续动作空间。
  • 在确定性奖励下仍能提升策略熵,促进随机探索。
  • 适合需要自发探索的强化学习场景,如复杂控制任务。

基于重试的目标(如 pass@K、max@K)通过优化多次采样轨迹中的最佳回报来促进探索,无需显式探索奖励。在离散动作空间中,ReMax 已证明可通过适应回报不确定性实现此目标。本文引入重试目标的路径导数估计器,并将其拓展至连续动作空间。我们研究了由此产生的学习动态,发现即使在确定性奖励下,ReMax 也能通过重塑策略梯度景观促进随机探索:一方面改变梯度方向,偏向更高策略熵;另一方面降低梯度幅值,减缓收敛速度。此外,我们发现 Adam 的自适应归一化可缓解这种幅值抑制,具体取决于其数值稳定参数。实验上,我们将该目标实例化为 ReMax Actor-Critic(ReMAC),一种使用路径导数估计器优化 ReMax 目标的离线策略演员-评论家算法。结果表明,ReMAC 可在无熵正则化情况下实现更高策略熵,性能媲美 SAC。

原文摘要 · Abstract (English)

Retry-based objectives such as pass@K and max@K optimize the best return obtained from multiple sampled trajectories, and recent work has shown that they can promote exploration without explicit exploration bonuses. In discrete action spaces, ReMax was shown to do so by adapting to return uncertainty. In this work, we introduce pathwise derivative estimators for retry objectives and use them to extend ReMax to continuous action spaces. We study the resulting learning dynamics and show that, even with deterministic rewards, ReMax can encourage stochastic exploration by reshaping the policy-gradient landscape. In particular, it alters gradients both in direction, biasing updates toward higher policy entropy, and in magnitude, damping gradients and slowing convergence. We further show that Adam's adaptive normalization can mitigate this damping, depending on its numerical stabilization parameter. Empirically, we instantiate this objective as ReMax Actor-Critic (ReMAC), an off-policy actor--critic algorithm that optimizes the ReMax objective using a pathwise derivative estimator. Our experiments show that ReMAC can promote higher policy entropy without entropy regularization and achieves performance comparable to SAC.

强化学习探索机制连续控制

Thank you to arXiv for use of its open access interoperability. PaperDance 不是 arXiv 官方产品;中文卡片由大模型生成,请以原文为准。