Beyond the 'Enemy-of-my-Enemy' Alliances: Coalitions in Networked Contest Games

Competitive resource allocation describes scenarios where multiple agents compete by spending their limited resources. For these settings, contest games offer a game-theoretic framework to analyze how players can efficiently invest their assets. Moreover, for this family of games, the resulting behavior can be modified through external interactions among the players. For instance, players could be able to make coalitions that allow budgetary transfers among them, trying to improve their outcomes. In this work, we study budgetary transfers in contest games played over networks. In particular, we aim to characterize the networks and players that guarantee that a transfer is beneficial for all players in the coalition. For this, we provide conditions for the existence of beneficial transfers. In addition, we provide a construction that guarantees that the benefit of making coalitions is independent of the graph structure and the chosen player to make an alliance.