Single Parameter FPT-Algorithms for Non-trivial Games

  • Vladimir Estivill-Castro
  • Mahdi Parsa
Part of the Lecture Notes in Computer Science book series (LNCS, volume 6460)


We know that k -Uniform Nash is W[2]-Complete when we consider imitation symmetric win-lose games (with k as the parameter) even when we have two players. However, this paper provides positive results regarding Nash equilibria. We show that consideration of sparse games or limitations of the support result in fixed-parameter algorithms with respect to one parameter only for the k -Uniform Nash problem. That is, we show that a sample uniform Nash equilibrium in r-sparse imitation symmetric win-lose games is not as hard because it can be found in FPT time (i.e polynomial in the size of the game, but maybe exponential in r). Moreover, we show that, although NP-Complete, the problem of Best Nash Equilibrium is also fix-parameter tractable.


Algorithmic Game Theory Computational Complexity 


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© Springer-Verlag Berlin Heidelberg 2011

Authors and Affiliations

  • Vladimir Estivill-Castro
    • 1
  • Mahdi Parsa
    • 1
  1. 1.School of ICTGriffith UniversityQueenslandAustralia

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