Non-oblivious Strategy Improvement

  • John Fearnley
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 6355)


We study strategy improvement algorithms for mean-payoff and parity games. We describe a structural property of these games, and we show that these structures can affect the behaviour of strategy improvement. We show how awareness of these structures can be used to accelerate strategy improvement algorithms. We call our algorithms non-oblivious because they remember properties of the game that they have discovered in previous iterations. We show that non-oblivious strategy improvement algorithms perform well on examples that are known to be hard for oblivious strategy improvement. Hence, we argue that previous strategy improvement algorithms fail because they ignore the structural properties of the game that they are solving.


Strategy Improvement Outgoing Edge Winning Strategy Positional Strategy Back Edge 
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 2010

Authors and Affiliations

  • John Fearnley
    • 1
  1. 1.Department of Computer ScienceUniversity of WarwickUK

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