Symmetric Strategy Improvement

  • Sven ScheweEmail author
  • Ashutosh Trivedi
  • Thomas Varghese
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 9135)


Symmetry is inherent in the definition of most of the two-player zero-sum games, including parity, mean-payoff, and discounted-payoff games. It is therefore quite surprising that no symmetric analysis techniques for these games exist. We develop a novel symmetric strategy improvement algorithm where, in each iteration, the strategies of both players are improved simultaneously. We show that symmetric strategy improvement defies Friedmann’s traps, which shook the belief in the potential of classic strategy improvement to be polynomial.


Model Check Strategy Improvement Tree Automaton Positional Strategy Graph 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 2015

Authors and Affiliations

  • Sven Schewe
    • 1
    Email author
  • Ashutosh Trivedi
    • 2
  • Thomas Varghese
    • 1
  1. 1.University of LiverpoolLiverpoolUK
  2. 2.Indian Institute of Technology BombayMumbaiIndia

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