Abstract
We consider a finitely defined game where the payoff for each player at each terminal point of the game is not a fixed quantity but varies according to probability distributions on the terminal points induced by the strategies chosen. We prove that if these payoffs have an upper-semicontinuous and convex valued structure then the game has an equilibrium. For this purpose the concept of a myopic equilibrium is introduced, a concept that generalizes that of a Nash equilibrium and applies to the games we consider. We answer in the affirmative a question posed by A. Neyman: if the payoffs of an infinitely repeated game of incomplete information on one side are a convex combination of the undiscounted payoffs and payoffs from a finite number of initial stages, does the game have an equilibrium?
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Dedicated to the memory of Andrzej Granas (1929–2019)
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Simon, R., Spież, S. & Toruńczyk, H. Games of incomplete information and myopic equilibria. Isr. J. Math. 241, 721–748 (2021). https://doi.org/10.1007/s11856-021-2111-7
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DOI: https://doi.org/10.1007/s11856-021-2111-7