Authors: Nicola Galesi, Navid Talebanfard and Jacobo Toran
Paper Information
Title: | Cops-Robber games and the resolution of Tseitin formulas |
Authors: | Nicola Galesi, Navid Talebanfard and Jacobo Toran |
Proceedings: | SAT Proceedings |
Editors: | Christoph M. Wintersteiger and Olaf Beyersdorff |
Keywords: | Resolution, Tseitin formulas, Games, Complexity measures |
Abstract: | ABSTRACT. We characterize several complexity measures for the resolution of Tseitin formulas in terms of a two person cop-robber game. Our game is a slight variation of the the one Seymour and Thomas used in order to characterize the tree-width parameter. For any undirected graph, by counting the number of cops needed in our game in order to catch a robber in it, we are able to exactly characterize the width, variable space and depth measures for the resolution of the Tseitin formula corresponding to that graph. We also give an exact game characterization of resolution variable space for any formula. We show that our game can be played in a monotonous way. This implies that the corresponding resolution measures on Tseitin formulas correspond to those under the restriction of regular resolution. Using our characterizations we improve the existing complexity bounds for Tseitin formulas showing that resolution width, depth and variable space coincide up to a logarithmic factor, and that variable space is bounded by the clause space times a logarithmic factor. |
Pages: | 16 |
Talk: | Jul 11 10:00 (Session 60F: Theory) |
Paper: |