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A detail-free mediator

Author

Listed:
  • Vida, Péter
  • Āzacis, Helmuts

Abstract

We present a cheap talk extension to any two-player, finite, complete information game, and ask what correlations over actions are implementable in Nash equilibria of the extended game. In the extension, players communicate repeatedly through a detail-free mediator that has been studied in Lehrer (1991) and in Gossner and Vieille (2001). The extension captures situations in which people can observe the opponentʼs face during the conversation. While Gossner and Vieille (2001) prove that no correlation can be securely implemented by using only this mediator, we prove a result closer to Lehrer (1991), namely, that the Nash equilibrium payoffs of the extended game essentially coincide with the correlated equilibrium payoffs of the underlying game. The contrasting results can be explained with our additional assumptions that the players can also communicate directly and, more importantly, the private messages sent to the mediator can be recorded and revealed later in the conversation.

Suggested Citation

  • Vida, Péter & Āzacis, Helmuts, 2013. "A detail-free mediator," Games and Economic Behavior, Elsevier, vol. 81(C), pages 101-115.
    • Handle: RePEc:eee:gamebe:v:81:y:2013:i:c:p:101-115
    DOI: 10.1016/j.geb.2013.04.004
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    References listed on IDEAS

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    Cited by:

    1. , & ,, 2013. "Implementation of communication equilibria by correlated cheap talk: The two-player case," Theoretical Economics, Econometric Society, vol. 8(1), January.
    2. Goltsman, Maria & Pavlov, Gregory, 2014. "Communication in Cournot oligopoly," Journal of Economic Theory, Elsevier, vol. 153(C), pages 152-176.
    3. Françoise Forges, 2006. "Correlated Equilibrium in Games with Incomplete Information Revisited," Theory and Decision, Springer, vol. 61(4), pages 329-344, December.

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    More about this item

    Keywords

    Correlated equilibrium; Detail-free mechanism; Mediated pre-play communication;
    All these keywords.

    JEL classification:

    • C72 - Mathematical and Quantitative Methods - - Game Theory and Bargaining Theory - - - Noncooperative Games

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