On Purification of Equilibrium in Bayesian Games and Ex-Post Nash Equilibrium
Working Paper No. 05-W12
Edward Cartwright and Myrna Wooders
ABSTRACT [article]
Kalai (2002) demonstrates that in semi anonymous Bayesian games with sufficiently many players any Bayesian equilibrium is approximately ex-post Nash. In this paper we demonstrate that the existence of an approximate expost Nash property implies a purification result of the standard sort for the original Bayesian game. We also provide an example showing that the bound we obtain on the distance of a purified approximate equilibrium from an exact equilibrium is tight.
Keywords and Phrases: Ex-post Nash equilibrium, noncooperative games, incomplete
information, purification, epsilon ex-post Nash equilibrium
JEL Classification Numbers: C72