A CoP model for graph-constrained coalition formation

Abstract

We focus on Graph-Constrained Coalition Formation (GCCF), a widely studied subproblem of coalition formation where the set of valid coalitions is constrained by a graph. We propose COP-GCCF, a novel approach that models GCCF as a COP. We then solve such COP with a highly-parallel GPU implementation of Bucket Elimination, which is able to exploit the high constraint tightness of COP-GCCF. Results on realistic graphs, i.e., a crawl of the Twitter social graph, show that our approach outperforms state of the art algorithms (i.e., DyCE and IDPG) by at least one order of magnitude, both in terms of runtime and memory.