On the Power of Mediators

  • Josep Díaz
  • Dieter Mitsche
  • Navin Rustagi
  • Jared Saia
Part of the Lecture Notes in Computer Science book series (LNCS, volume 5929)


We consider a problem at the intersection of distributed computing and game theory, namely: Is it possible to achieve the “windfall of malice” even without the actual presence of malicious players? Our answer to this question is “Yes and No”. Our positive result is that for the virus inoculation game, it is possible to achieve the windfall of malice by use of a mediator. Our negative result is that for symmetric congestion games that are known to have a windfall of malice, it is not possible to design a mediator that achieves this windfall. In proving these two results, we develop novel techniques for mediator design that we believe will be helpful for creating non-trivial mediators to improve social welfare in a large class of games.


Nash Equilibrium Social Welfare Social Cost Related Equilibrium Congestion 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 2009

Authors and Affiliations

  • Josep Díaz
    • 1
  • Dieter Mitsche
    • 1
  • Navin Rustagi
    • 1
  • Jared Saia
    • 2
  1. 1.Deptartament Llenguatges i SistemesUniversitat Politecnica de Catalunya 
  2. 2.Department of Computer ScienceUniversity of New Mexico 

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