Date and Location: Monday, November 28, 12:00, A 0.23
Presenter: Elnaz Bajoori
Title: On the definition of perfect equilibrium in Bayesian Games
Authors: Elnaz Bajoori, János Flesch, Dries Vermeulen

Abstract:  We develop the definition of perfect equilibrium in Bayesian games where players may have infinitely many types and actions. We formulate several definitions of perfection in this setting. The difference between the definitions arises on one hand from using two different types of strategies; behavior strategies and distributional strategies and on the other hand from using various notions of convergence such as uniform, pointwise and almost everywhere pointwise convergence. Moreover, we discuss the relations between the definitions.

Additionally, we examine these definitions of perfect equilibrium in a second-price auction with incomplete information, in which the bidders have no dominant strategies. In this auction, perfect equilibrium selects a unique solution in a certain class of strategies and rules out less intuitive equilibria. We show that the selected perfect equilibrium is not sincere.