Sparse Games Are Hard

  • Xi Chen
  • Xiaotie Deng
  • Shang-Hua Teng
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4286)


A two-player game is sparse if most of its payoff entries are zeros. We show that the problem of computing a Nash equilibrium remains PPAD-hard to approximate in fully polynomial time for sparse games. On the algorithmic side, we give a simple and polynomial-time algorithm for finding exact Nash equilibria in a class of sparse win-lose games.


Nash Equilibrium Polynomial Time Internal Node Nonzero Entry Approximate Nash Equilibrium 
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Copyright information

© Springer-Verlag Berlin Heidelberg 2006

Authors and Affiliations

  • Xi Chen
    • 1
  • Xiaotie Deng
    • 2
  • Shang-Hua Teng
    • 3
  1. 1.Department of Computer ScienceTsinghua UniversityBeijing
  2. 2.Department of Computer ScienceCity University of Hong KongHong Kong
  3. 3.Department of Computer ScienceBoston UniversityBoston

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