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On the Hardness and Existence of Quasi-Strict Equilibria

  • Felix Brandt
  • Felix Fischer
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4997)

Abstract

This paper investigates the computational properties of quasi-strict equilibrium, an attractive equilibrium refinement proposed by Harsanyi, which was recently shown to always exist in bimatrix games. We prove that deciding the existence of a quasi-strict equilibrium in games with more than two players is NP-complete. We further show that, in contrast to Nash equilibrium, the support of quasi-strict equilibrium in zero-sum games is unique and propose a linear program to compute quasi-strict equilibria in these games. Finally, we prove that every symmetric multi-player game where each player has two actions at his disposal contains an efficiently computable quasi-strict equilibrium which may itself be asymmetric.

Keywords

Nash Equilibrium Positive Probability Pure Nash Equilibrium Graphical Game Symmetric Game 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer-Verlag Berlin Heidelberg 2008

Authors and Affiliations

  • Felix Brandt
    • 1
  • Felix Fischer
    • 1
  1. 1.Institut für InformatikUniversität MünchenMünchenGermany

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