On approximating MIS over B-1-VPG graphs

In this paper, we present an approximation algorithm for the maximum independent set (MIS) problem over the class of B-1-VPG graphs when the input is specified by a B-1-VPG representation. We obtain a 6(log n)(2)-approximation algorithm running in O(n(logn)(3)) time. This is an improvement over the previously best n(epsilon)-approximation algorithm [J. Fox and J. Pach, Computing the independence number of intersection graphs, in Proc. Twenty-Second Annual ACM-SIAM Symp. Discrete Algorithms (SODA 2011), 2011, pp. 1161-1165, doi:10.1137/1.9781611973082.87] (for some fixed epsilon > 0) designed for some subclasses of string graphs, on B-1-VPG graphs.