English

Polytopality of simple games

Combinatorics 2023-09-27 v1

Abstract

The Bier sphere Bier(G)=Bier(K)=KΔKBier(\mathcal{G}) = Bier(K) = K\ast_\Delta K^\circ and the canonical fan Fan(Γ)=Fan(K)Fan(\Gamma) = Fan(K) are combinatorial/geometric companions of a simple game G=(P,Γ)\mathcal{G} = (P,\Gamma) (equivalently the associated simplicial complex KK), where PP is the set of players, Γ2P\Gamma\subseteq 2^P is the set of wining coalitions, and K=2PΓK = 2^P\setminus \Gamma is the simplicial complex of losing coalitions. We characterize roughly weighted majority games as the games Γ\Gamma such that Bier(G)Bier(\mathcal{G}) (respectively Fan(Γ)Fan(\Gamma)) is canonically polytopal (canonically pseudo-polytopal) and show, by an experimental/theoretical argument, that all simple games with at most five players are polytopal.

Keywords

Cite

@article{arxiv.2309.14848,
  title  = {Polytopality of simple games},
  author = {Marinko Timotijević and Rade T. Živaljević and Filip D. Jevtić},
  journal= {arXiv preprint arXiv:2309.14848},
  year   = {2023}
}
R2 v1 2026-06-28T12:32:39.206Z