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arXiv · 1912.11206

Learning to Combat Compounding-Error in Model-Based Reinforcement Learning

Abstract

Despite its potential to improve sample complexity versus model-free approaches, model-based reinforcement learning can fail catastrophically if the model is inaccurate. An algorithm should ideally be able to trust an imperfect model over a reasonably long planning horizon, and only rely on model-free updates when the model errors get infeasibly large. In this paper, we investigate techniques for choosing the planning horizon on a state-dependent basis, where a state's planning horizon is determined by the maximum cumulative model error around that state. We demonstrate that these state-dependent model errors can be learned with Temporal Difference methods, based on a novel approach of temporally decomposing the cumulative model errors. Experimental results show that the proposed method can successfully adapt the planning horizon to account for state-dependent model accuracy, significantly improving the efficiency of policy learning compared to model-based and model-free baselines.

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Chenjun Xiao, Yifan Wu, Chen Ma, Dale Schuurmans, Martin Müller. 2019-12-24. Learning to Combat Compounding-Error in Model-Based Reinforcement Learning. https://arxiv.org/abs/1912.11206

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