Unilateral Support Equilibrium, Berge Equilibrium, and Team Problems Solutions

  • Bertrand CrettezEmail author
Original Article


We compare two notions of equilibrium for other-regarding agents, namely Berge and unilateral support equilibria. A Berge equilibrium is a strategy profile such that the teammates of each agent choose their strategies in order to maximize his utility. A unilateral support equilibrium is a strategy profile such that the teammates of each agent non-cooperatively choose their strategies to maximize his utility. By definition the level of cooperation in a unilateral support equilibrium is no higher than in a Berge equilibrium. Yet, relying on ideas from Team theory, we provide conditions under which a unilateral support equilibrium is also a Berge equilibrium. We also provide conditions under which a unilateral support equilibrium is a Berge–Vaisman equilibrium, i.e., a strategy profile which is a Berge equilibrium and such that the payoff of each player is no lower than his maximin value.


Berge equilibrium Berge–Vaisman equilibrium Berge–Nash equilibrium Unilateral support equilibrium Team optimal solution Person-by-person optimal solution Mutually beneficial practice 

JEL Classification

C7 D 74 



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Copyright information

© The Indian Econometric Society 2019

Authors and Affiliations

  1. 1.Université Panthéon-Assas, Paris II, CRED, EA 7321ParisFrance

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