TTree: Tree-based state generalization with temporally abstract actions - Robotics Institute Carnegie Mellon University

TTree: Tree-based state generalization with temporally abstract actions

William Uther and Manuela Veloso
Conference Paper, Proceedings of International Symposium on Abstraction, Reformulation, and Approximation (SARA '02), pp. 308 - 315, August, 2002

Abstract

In this paper we describe the Trajectory Tree, or TTree, algorithm. TTree uses a small set of supplied policies to help solve a Semi-Markov Decision Problem (SMDP). The algorithm uses a learned tree based discretization of the state space as an abstract state description and both user supplied and auto-generated policies as temporally abstract actions. It uses a generative model of the world to sample the transition function for the abstract SMDP defined by those state and temporal abstractions, and then finds a policy for that abstract SMDP. This policy for the abstract SMDP can then be mapped back to a policy for the base SMDP, solving the supplied problem. In this paper we present the TTree algorithm and give empirical comparisons to other SMDP algorithms showing its effectiveness.

BibTeX

@conference{Uther-2002-8524,
author = {William Uther and Manuela Veloso},
title = {TTree: Tree-based state generalization with temporally abstract actions},
booktitle = {Proceedings of International Symposium on Abstraction, Reformulation, and Approximation (SARA '02)},
year = {2002},
month = {August},
pages = {308 - 315},
}