Q-learning and policy iteration algorithms for stochastic shortest path problems
We consider the stochastic shortest path problem, a classical finite-state Markovian decision problem with a termination state, and we propose new convergent Q-learning algorithms that combine elements of policy iteration and classical Q-learning/value iteration. These algorithms are related to the...
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| Other Authors: | |
| Format: | Article |
| Language: | en_US |
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Springer-Verlag
2015
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| Online Access: | http://hdl.handle.net/1721.1/93745 https://orcid.org/0000-0001-6909-7208 |
| _version_ | 1811082971057225728 |
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| author | Yu, Huizhen Bertsekas, Dimitri P. |
| author2 | Massachusetts Institute of Technology. Department of Electrical Engineering and Computer Science |
| author_facet | Massachusetts Institute of Technology. Department of Electrical Engineering and Computer Science Yu, Huizhen Bertsekas, Dimitri P. |
| author_sort | Yu, Huizhen |
| collection | MIT |
| description | We consider the stochastic shortest path problem, a classical finite-state Markovian decision problem with a termination state, and we propose new convergent Q-learning algorithms that combine elements of policy iteration and classical Q-learning/value iteration. These algorithms are related to the ones introduced by the authors for discounted problems in Bertsekas and Yu (Math. Oper. Res. 37(1):66-94, 2012). The main difference from the standard policy iteration approach is in the policy evaluation phase: instead of solving a linear system of equations, our algorithm solves an optimal stopping problem inexactly with a finite number of value iterations. The main advantage over the standard Q-learning approach is lower overhead: most iterations do not require a minimization over all controls, in the spirit of modified policy iteration. We prove the convergence of asynchronous deterministic and stochastic lookup table implementations of our method for undiscounted, total cost stochastic shortest path problems. These implementations overcome some of the traditional convergence difficulties of asynchronous modified policy iteration, and provide policy iteration-like alternative Q-learning schemes with as reliable convergence as classical Q-learning. We also discuss methods that use basis function approximations of Q-factors and we give an associated error bound. |
| first_indexed | 2024-09-23T12:15:58Z |
| format | Article |
| id | mit-1721.1/93745 |
| institution | Massachusetts Institute of Technology |
| language | en_US |
| last_indexed | 2024-09-23T12:15:58Z |
| publishDate | 2015 |
| publisher | Springer-Verlag |
| record_format | dspace |
| spelling | mit-1721.1/937452022-09-28T00:50:13Z Q-learning and policy iteration algorithms for stochastic shortest path problems Yu, Huizhen Bertsekas, Dimitri P. Massachusetts Institute of Technology. Department of Electrical Engineering and Computer Science Massachusetts Institute of Technology. Laboratory for Information and Decision Systems Bertsekas, Dimitri P. Yu, Huizhen Bertsekas, Dimitri P. We consider the stochastic shortest path problem, a classical finite-state Markovian decision problem with a termination state, and we propose new convergent Q-learning algorithms that combine elements of policy iteration and classical Q-learning/value iteration. These algorithms are related to the ones introduced by the authors for discounted problems in Bertsekas and Yu (Math. Oper. Res. 37(1):66-94, 2012). The main difference from the standard policy iteration approach is in the policy evaluation phase: instead of solving a linear system of equations, our algorithm solves an optimal stopping problem inexactly with a finite number of value iterations. The main advantage over the standard Q-learning approach is lower overhead: most iterations do not require a minimization over all controls, in the spirit of modified policy iteration. We prove the convergence of asynchronous deterministic and stochastic lookup table implementations of our method for undiscounted, total cost stochastic shortest path problems. These implementations overcome some of the traditional convergence difficulties of asynchronous modified policy iteration, and provide policy iteration-like alternative Q-learning schemes with as reliable convergence as classical Q-learning. We also discuss methods that use basis function approximations of Q-factors and we give an associated error bound. United States. Air Force (Grant FA9550-10-1-0412) National Science Foundation (U.S.) (Grant ECCS-0801549) 2015-02-03T19:29:00Z 2015-02-03T19:29:00Z 2012-04 Article http://purl.org/eprint/type/JournalArticle 0254-5330 1572-9338 http://hdl.handle.net/1721.1/93745 Yu, Huizhen, and Dimitri P. Bertsekas. “Q-Learning and Policy Iteration Algorithms for Stochastic Shortest Path Problems.” Annals of Operations Research 208, no. 1 (April 18, 2012): 95–132. https://orcid.org/0000-0001-6909-7208 en_US http://dx.doi.org/10.1007/s10479-012-1128-z Annals of Operations Research Creative Commons Attribution-Noncommercial-Share Alike http://creativecommons.org/licenses/by-nc-sa/4.0/ application/pdf Springer-Verlag Prof. Bertsekas via Chris Sherratt |
| spellingShingle | Yu, Huizhen Bertsekas, Dimitri P. Q-learning and policy iteration algorithms for stochastic shortest path problems |
| title | Q-learning and policy iteration algorithms for stochastic shortest path problems |
| title_full | Q-learning and policy iteration algorithms for stochastic shortest path problems |
| title_fullStr | Q-learning and policy iteration algorithms for stochastic shortest path problems |
| title_full_unstemmed | Q-learning and policy iteration algorithms for stochastic shortest path problems |
| title_short | Q-learning and policy iteration algorithms for stochastic shortest path problems |
| title_sort | q learning and policy iteration algorithms for stochastic shortest path problems |
| url | http://hdl.handle.net/1721.1/93745 https://orcid.org/0000-0001-6909-7208 |
| work_keys_str_mv | AT yuhuizhen qlearningandpolicyiterationalgorithmsforstochasticshortestpathproblems AT bertsekasdimitrip qlearningandpolicyiterationalgorithmsforstochasticshortestpathproblems |