Home > Research > Publications & Outputs > Faster Algorithm for Turn-based Stochastic Game...

Links

Text available via DOI:

View graph of relations

Faster Algorithm for Turn-based Stochastic Games with Bounded Treewidth.

Research output: Contribution in Book/Report/Proceedings - With ISBN/ISSNConference contribution/Paperpeer-review

Published
Close
Publication date16/01/2023
Host publication34th Annual ACM-SIAM Symposium on Discrete Algorithms, SODA 2023
PublisherCurran Associates, Inc.
Pages4590-4605
Number of pages16
ISBN (electronic)9781611977554
<mark>Original language</mark>English

Publication series

NameProceedings of the Annual ACM-SIAM Symposium on Discrete Algorithms
Volume2023-January

Abstract

Turn-based stochastic games (aka simple stochastic games) are two-player zero-sum games played on directed graphs with probabilistic transitions. The goal of player-max is to maximize the probability to reach a target state against the adversarial player-min. These games lie in NP ∩ coNP and are among the rare combinatorial problems that belong to this complexity class for which the existence of polynomial-time algorithm is a major open question. While randomized sub-exponential time algorithm exists, all known deterministic algorithms require exponential time in the worst-case. An important open question has been whether faster algorithms can be obtained parametrized by the treewidth of the game graph. Even deterministic sub-exponential time algorithm for constant treewidth turn-based stochastic games has remain elusive. In this work our main result is a deterministic algorithm to solve turn-based stochastic games that, given a game with n states, treewidth at most t, and the bit-complexity of the probabilistic transition function log D, has running time (Equation presented). In particular, our algorithm is quasi-polynomial time for games with constant or poly-logarithmic treewidth.