2019/05/07 by Seungyul Han, Han, Seungyul, Youngchul Sung +1 · 3 citations
Computer Science · Decision Sciences · #Reinforcement Learning in Robotics #Advanced Bandit Algorithms Research #Adaptive Dynamic Programming Control
paper · pdf · doi:10.48550/arxiv.1905.02363
In importance sampling (IS)-based reinforcement learning algorithms such as\nProximal Policy Optimization (PPO), IS weights are typically clipped to avoid\nlarge variance in learning. However, policy update from clipped statistics\ninduces large bias in tasks with high action dimensions, and bias from clipping\nmakes it difficult to reuse old samples with large IS weights. In this paper,\nwe consider PPO, a representative on-policy algorithm, and propose its\nimprovement by dimension-wise IS weight clipping which separately clips the IS\nweight of each action dimension to avoid large bias and adaptively controls the\nIS weight to bound policy update from the current policy. This new technique\nenables efficient learning for high action-dimensional tasks and reusing of old\nsamples like in off-policy learning to increase the sample efficiency.\nNumerical results show that the proposed new algorithm outperforms PPO and\nother RL algorithms in various Open AI Gym tasks.\n