This paper presents a game-theoretic model of network formation, which allows agents to enter bilateral alliances and to extract payoffs from enemies. Each pair of agents creates a surplus of one, which allies divide in equal parts. If agents are enemies, then the agent with more allies obtains...

We investigate the role of networks of military alliances in preventing or encouraging wars between groups of countries. A country is vulnerable to attack if there is some fully-allied group of countries that can defeat that country and its (remaining) allies based on a function of their...

We look at syndication in the venture capital industry. Investments conducted by syndicates are believed to have better chances of being successful, measured by the survival probability of portfolio companies or by successful exits. Using a novel and large dataset, covering several countries,...

Community enforcement is an important device for sustaining efficiency in some repeated games of cooperation. We investigate cooperation when information about players' reputations spreads to their future partners through links in a social network that connects them. We find that information...