The Enemy of My Enemy Is My Friend: A New Condition for Network Games

Hideto Koizumi, Hitotsubashi University

Abstract: Group formation tends to involve peer effects. I provide a new sufficient condition for the non-emptiness of the core of network formation games that involve pairwise complementarities between peers. My condition allows for a novel class of preferences that are relevant to political alliances and publicly open friendship networks.

Read the full working paper here (PDF).