Robust equilibria under non-common priors

• 成果类型: Article
• 署名作者: Oyama, Daisuke; Tercieux, Olivier
• 署名单位: Hitotsubashi University; Centre National de la Recherche Scientifique (CNRS); Paris School of Economics
• 刊物名称: JOURNAL OF ECONOMIC THEORY
• ISSN/ISSBN: 0022-0531
• DOI: 10.1016/j.jet.2009.10.009
• 发表日期: 2010
• 页码: 752-784
• 关键词: Incomplete information; Robustness; Common prior assumption; Higher order belief

摘要

This paper considers the robustness of equilibria to a small amount of incomplete information, where players are allowed to have heterogeneous priors. An equilibrium of a complete information game is robust to incomplete information under non-common priors if for every incomplete information game where each player's prior assigns high probability on the event that the players know at arbitrarily high order that the payoffs are given by the complete information game, there exists a Bayesian Nash equilibrium that generates behavior close to the equilibrium in consideration. It is shown that for generic games, an equilibrium is robust under non-common priors if and only if it is the unique rationalizable action profile. Set-valued concepts are also introduced, and for generic games, a smallest robust set is shown to exist and coincide with the set of a posteriori equilibria. (C) 2009 Elsevier Inc. All rights reserved.