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International Journal of Game Theory

, Volume 37, Issue 3, pp 371–386 | Cite as

Cournot–Walras equilibrium as a subgame perfect equilibrium

  • Francesca Busetto
  • Giulio Codognato
  • Sayantan Ghosal
Original Paper

Abstract

In this paper, we investigate the problem of the strategic foundation of the Cournot–Walras equilibrium approach. To this end, we respecify à la Cournot–Walras the mixed version of a model of simultaneous, noncooperative exchange, originally proposed by Lloyd S. Shapley. We show, through an example, that the set of the Cournot–Walras equilibrium allocations of this respecification does not coincide with the set of the Cournot–Nash equilibrium allocations of the mixed version of the original Shapley’s model. As the nonequivalence, in a one-stage setting, can be explained by the intrinsic two-stage nature of the Cournot–Walras equilibrium concept, we are led to consider a further reformulation of the Shapley’s model as a two-stage game, where the atoms move in the first stage and the atomless sector moves in the second stage. Our main result shows that the set of the Cournot–Walras equilibrium allocations coincides with a specific set of subgame perfect equilibrium allocations of this two-stage game, which we call the set of the Pseudo–Markov perfect equilibrium allocations.

Keywords

Walras equilibrium Cournot–Nash equilibrium Cournot–Walras equilibrium Subgame perfect equilibrium 

JEL Classification

C72 D51 

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Copyright information

© Springer-Verlag 2008

Authors and Affiliations

  • Francesca Busetto
    • 1
  • Giulio Codognato
    • 1
  • Sayantan Ghosal
    • 2
  1. 1.Dipartimento di Scienze EconomicheUniversità degli Studi di UdineUdineItaly
  2. 2.Department of EconomicsUniversity of WarwickCoventryUK

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