Elsevier

Games and Economic Behavior

Volume 67, Issue 2, November 2009, Pages 363-375
Games and Economic Behavior

Consistency of beliefs and epistemic conditions for Nash and correlated equilibria

https://doi.org/10.1016/j.geb.2009.02.003Get rights and content

Abstract

A consistency condition (action-consistency) on the interim beliefs of players in a game is introduced. Action-consistency is weaker than common priors and, unlike common priors, is characterized by a “no-bets” condition on verifiable events. Using action-consistency, we provide epistemic conditions to Nash and correlated equilibria weakening the common knowledge restrictions in Aumann and Brandenburger [Aumann, R., Brandenburger, A., 1995. Epistemic conditions for Nash equilibrium. Econometrica 63, 1161–1180] and Aumann [Aumann, R., 1987. Correlated equilibrium as an expression of Bayesian rationality. Econometrica 55, 1–18].

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