How is group conflict over a public-good prize affected when individuals are active members of multiple groups simultaneously? To investigate this question, I introduce a simple model of Tullock group contest: individuals are partitioned into two groups in two dimensions each, the group-level...

We study a dynamic multi-stage contest that resolves in each stage only with a given probability. Assuming that there is unobservable heterogeneity in intrinsic motivations we derive properties of the equilibrium efforts across the different stages. Whereas in the corresponding complete...

We consider two players' choice about the formation of an alliance ahead of conflict in a framework with incomplete information about the strength of co-players. When deciding on alliance formation, players anticipate the self-selection of other players and the informational value of own and...

This paper surveys some of the strategic aspects that emerge if players fight in an alliance against an enemy. The survey includes the free-rider problem and the hold-up problem that emerges in the baseline model, the role of supermodularity in alliance members' effort contributions, the role of...

We study the role of an imbalance in fighting strengths when players bargain in the shadow of conflict. Our experimental results suggest: In a simple bargaining game with an exogenous mediation proposal, the likelihood of conflict is independent of the balance of power. If bargaining involves...

In many real-world contests (political elections / lobbying for public projects), contestants try to engage supporters (unemployed youth / local residents) to fight for them. Such contests have the following features: a significant part of a contestant's supporter compensation is contingent upon...

In the world of satin bowerbirds, the male-birds engage in a contest among themselves to win their mates: they spend considerable time and effort in decorating their own bowers, and then attempt to destroy the decorations of their rivals' bowers. The female-birds, in turn, select their mates on...

This paper studies the attack-and-defence game between a web user and a whole set of players over this user's ‘valuable secrets.' The number and type of these valuable secrets are the user's private information. Attempts to tap information as well as privacy protection are costly. The...

This study compares contests with exogenous alliance formation under proportional sharing rules with contests among individual players in a laboratory setting. The standard equilibrium predictions are identical for all players because the proportional rule ensures the same payoff incentives for...

We study conflict between two groups of individuals. Using Schaffer's (1988) concept of evolutionary stability we provide an evolutionary underpinning for in-group altruism combined with spiteful behavior towards members of the rival out-group. We characterize the set of evolutionarily stable...