Correlated Equilibrium via Hierarchies of Beliefs

Du, Songzi (2009): Correlated Equilibrium via Hierarchies of Beliefs.

Abstract

We study a model of correlated equilibrium where every player takes actions based on his hierarchies of beliefs (belief on what other players will do, on what other players believe about others will do, etc.) intrinsic to the game. Our model does away with messages from outside mediator that are usually assumed in the interpretation of correlated equilibrium. We characterize in every finite, complete information game the exact sets of correlated equilibria (both subjective and objective) that can be obtained conditioning on hierarchies of beliefs; the characterizations rely on a novel iterated deletion procedure. If the procedure ends after k rounds of deletion for a correlated equilibrium obtained from hierarchies of beliefs, then players in the equilibrium need to reason to at most k-th order beliefs. Further conceptual and geometric properties of the characterizations are studied.

• Item Type: MPRA Paper
• Language: English
• Keywords: game theory; correlated equilibrium; higher order beliefs; purification; intrinsic correlation
• Subjects: D - Microeconomics > D8 - Information, Knowledge, and Uncertainty > D80 - General; C - Mathematical and Quantitative Methods > C7 - Game Theory and Bargaining Theory > C72 - Noncooperative Games

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