Solving POMDPs by Searching in Policy Space

Eric A. Hansen

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arXiv · 1301.7380

Solving POMDPs by Searching in Policy Space

Eric A. Hansen

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Abstract

Most algorithms for solving POMDPs iteratively improve a value function that implicitly represents a policy and are said to search in value function space. This paper presents an approach to solving POMDPs that represents a policy explicitly as a finite-state controller and iteratively improves the controller by search in policy space. Two related algorithms illustrate this approach. The first is a policy iteration algorithm that can outperform value iteration in solving infinitehorizon POMDPs. It provides the foundation for a new heuristic search algorithm that promises further speedup by focusing computational effort on regions of the problem space that are reachable, or likely to be reached, from a start state.

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Eric A. Hansen. 2013-01-30. Solving POMDPs by Searching in Policy Space. https://arxiv.org/abs/1301.7380

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