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arXiv · 1901.01977

Accelerating Goal-Directed Reinforcement Learning by Model Characterization

Shoubhik Debnath·Gaurav Sukhatme·Lantao Liu
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Abstract

We propose a hybrid approach aimed at improving the sample efficiency in goal-directed reinforcement learning. We do this via a two-step mechanism where firstly, we approximate a model from Model-Free reinforcement learning. Then, we leverage this approximate model along with a notion of reachability using Mean First Passage Times to perform Model-Based reinforcement learning. Built on such a novel observation, we design two new algorithms - Mean First Passage Time based Q-Learning (MFPT-Q) and Mean First Passage Time based DYNA (MFPT-DYNA), that have been fundamentally modified from the state-of-the-art reinforcement learning techniques. Preliminary results have shown that our hybrid approaches converge with much fewer iterations than their corresponding state-of-the-art counterparts and therefore requiring much fewer samples and much fewer training trials to converge.

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Shoubhik Debnath, Gaurav Sukhatme, Lantao Liu. 2019-01-04. Accelerating Goal-Directed Reinforcement Learning by Model Characterization. https://arxiv.org/abs/1901.01977

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