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On the Openness of Unique Pure-Strategy Nash Equilibrium

Anna A. Klis ORCID logo


This paper investigates whether small perturbations to a game with continuous strategy spaces and unique Nash equilibrium also yields a game with unique equilibrium. The answer is affirmative for games with smooth payoffs, differentiable strict concavity in own actions, and transversal intersection of best response curves. Though intuitive for games with unique interior equilibrium, this result holds even for equilibria at the boundaries of strategy sets.


I thank Dr. Maxwell Stinchcombe for his unfailing support, as well as three anonymous reviewers for the time and effort spent on my paper.


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Published Online: 2018-01-04

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