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On the Existence of Bayesian Cournot Equilibrium

Author

Listed:
  • Ezra Einy

    (Department of Economics Ben-Gurion University, Israel)

  • Ori Haimanko

    (Department of Economics, Ben Gurion University, Israel)

  • Diego Moreno

    (Departamento de Econom?a, Universidad Carlos III de Madrid, Spain)

  • Benyamin Shitovitz

    (Department of Economics, University of Haifa, Israel)

Abstract

We show that when firms have asymmetric information about the market demand and theirs costs, a (Bayesian) Cournot equilibrium in pure strategies may not exist, or be unique. In fact, we are able to construct surprisingly simple and robust examples of duopolies with these features. However, we also find sufficient conditions for existence, and for uniqueness, of Cournot equilibrium in a certain class of industries. More general results arise when negative prices are possible.

Suggested Citation

  • Ezra Einy & Ori Haimanko & Diego Moreno & Benyamin Shitovitz, 2007. "On the Existence of Bayesian Cournot Equilibrium," Working Papers 0715, Ben-Gurion University of the Negev, Department of Economics.
    • Handle: RePEc:bgu:wpaper:0715
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    References listed on IDEAS

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    1. Esther Gal-or, 1986. "Information Transmission—Cournot and Bertrand Equilibria," The Review of Economic Studies, Review of Economic Studies Ltd, vol. 53(1), pages 85-92.
    2. William Novshek, 1985. "On the Existence of Cournot Equilibrium," The Review of Economic Studies, Review of Economic Studies Ltd, vol. 52(1), pages 85-98.
    3. Lagerlof, Johan N.M., 2007. "Insisting on a non-negative price: Oligopoly, uncertainty, welfare, and multiple equilibria," International Journal of Industrial Organization, Elsevier, vol. 25(4), pages 861-875, August.
    4. Szidarovszky, F & Yakowitz, S, 1977. "A New Proof of the Existence and Uniqueness of the Cournot Equilibrium," International Economic Review, Department of Economics, University of Pennsylvania and Osaka University Institute of Social and Economic Research Association, vol. 18(3), pages 787-789, October.
    5. Gal-Or, Esther, 1985. "Information Sharing in Oligopoly," Econometrica, Econometric Society, vol. 53(2), pages 329-343, March.
    6. Einy, Ezra & Haimanko, Ori & Moreno, Diego & Shitovitz, Benyamin, 2010. "On the existence of Bayesian Cournot equilibrium," Games and Economic Behavior, Elsevier, vol. 68(1), pages 77-94, January.
    7. Einy, Ezra & Moreno, Diego & Shitovitz, Benyamin, 2003. "The value of public information in a Cournot duopoly," Games and Economic Behavior, Elsevier, vol. 44(2), pages 272-285, August.
    8. Sakai, Yasuhiro, 1985. "The value of information in a simple duopoly model," Journal of Economic Theory, Elsevier, vol. 36(1), pages 36-54, June.
    9. Amir, R., 1996. "Cournot oligopoly and theory of supermodular games," LIDAM Reprints CORE 1228, Université catholique de Louvain, Center for Operations Research and Econometrics (CORE).
    10. Amir, Rabah, 1996. "Cournot Oligopoly and the Theory of Supermodular Games," Games and Economic Behavior, Elsevier, vol. 15(2), pages 132-148, August.
    11. Einy, Ezra & Moreno, Diego & Shitovitz, Benyamin, 2002. "Information Advantage in Cournot Oligopoly," Journal of Economic Theory, Elsevier, vol. 106(1), pages 151-160, September.
    12. Vives, Xavier, 1988. "Aggregation of Information in Large Cournot Markets," Econometrica, Econometric Society, vol. 56(4), pages 851-876, July.
    13. Xavier Vives, 2001. "Oligopoly Pricing: Old Ideas and New Tools," MIT Press Books, The MIT Press, edition 1, volume 1, number 026272040x, April.
    14. Vives, Xavier, 1990. "Nash equilibrium with strategic complementarities," Journal of Mathematical Economics, Elsevier, vol. 19(3), pages 305-321.
    15. Vives, Xavier, 1984. "Duopoly information equilibrium: Cournot and bertrand," Journal of Economic Theory, Elsevier, vol. 34(1), pages 71-94, October.
    16. repec:bla:ausecp:v:37:y:1998:i:4:p:363-71 is not listed on IDEAS
    17. Shlomit Hon‐Snir & Benyamin Shitovitz & Menahem Spiegel, 2010. "Bayesian Equilibrium in a Public Good Economy," Journal of Public Economic Theory, Association for Public Economic Theory, vol. 12(2), pages 387-398, April.
    18. Kukushkin, Nikolai S., 1994. "A fixed-point theorem for decreasing mappings," Economics Letters, Elsevier, vol. 46(1), pages 23-26, September.
    19. Raith, Michael, 1996. "A General Model of Information Sharing in Oligopoly," Journal of Economic Theory, Elsevier, vol. 71(1), pages 260-288, October.
    20. Lagerlöf Johan N.M., 2006. "Equilibrium Uniqueness in a Cournot Model with Demand Uncertainty," The B.E. Journal of Theoretical Economics, De Gruyter, vol. 6(1), pages 1-8, December.
    21. Milgrom, Paul & Roberts, John, 1990. "Rationalizability, Learning, and Equilibrium in Games with Strategic Complementarities," Econometrica, Econometric Society, vol. 58(6), pages 1255-1277, November.
    22. Carl Shapiro, 1986. "Exchange of Cost Information in Oligopoly," The Review of Economic Studies, Review of Economic Studies Ltd, vol. 53(3), pages 433-446.
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    Citations

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    Cited by:

    1. Francesco Sinopoli & Christopher Künstler & Claudia Meroni & Carlos Pimienta, 2023. "Poisson–Cournot games," Economic Theory, Springer;Society for the Advancement of Economic Theory (SAET), vol. 75(3), pages 803-840, April.
      • Francesco De Sinopoli & Christopher Kunstler & Claudia Meroni & Carlos Pimienta, 2020. "Poisson-Cournot Games," Discussion Papers 2020-07, School of Economics, The University of New South Wales.
    2. Ali Kakhbod & Asuman Ozdaglar & Ian Schneider, 2018. "Selling Wind," Papers 1812.11420, arXiv.org.
    3. Oriol Carbonell-Nicolau & Richard P. McLean, 2018. "On the Existence of Nash Equilibrium in Bayesian Games," Mathematics of Operations Research, INFORMS, vol. 43(2), pages 100-129, February.
    4. Einy, Ezra & Haimanko, Ori & Moreno, Diego & Shitovitz, Benyamin, 2010. "On the existence of Bayesian Cournot equilibrium," Games and Economic Behavior, Elsevier, vol. 68(1), pages 77-94, January.
    5. Tseng, Chin-Yi & Lee, Chia-Yen & Wang, Qunwei & Wu, Changsong, 2022. "Data envelopment analysis and stochastic equilibrium analysis for market power investigation in a bi-level market," Transportation Research Part E: Logistics and Transportation Review, Elsevier, vol. 161(C).
    6. Arsen Palestini & Ilaria Poggio, 2015. "A Bayesian potential game to illustrate heterogeneity in cost/benefit characteristics," International Review of Economics, Springer;Happiness Economics and Interpersonal Relations (HEIRS), vol. 62(1), pages 23-39, March.
    7. Cabolis, C. & Manasakis, C., 2016. "R&D investments fostering horizontal mergers," UC3M Working papers. Economics 23280, Universidad Carlos III de Madrid. Departamento de Economía.
    8. Einy, Ezra & Haimanko, Ori, 2020. "Equilibrium existence in games with a concave Bayesian potential," Games and Economic Behavior, Elsevier, vol. 123(C), pages 288-294.
    9. Richter, Jan & Viehmann, Johannes, 2014. "The value of information in explicit cross-border capacity auction regimes in electricity markets," Energy Policy, Elsevier, vol. 70(C), pages 74-84.
    10. Deb, Joyee & Kalai, Ehud, 2015. "Stability in large Bayesian games with heterogeneous players," Journal of Economic Theory, Elsevier, vol. 157(C), pages 1041-1055.
    11. Richter, Jan, 2013. "Incomplete Information in Cournot Oligopoly: The Case of Unknown Production Capacities," EWI Working Papers 2013-1, Energiewirtschaftliches Institut an der Universitaet zu Koeln (EWI).
    12. Eliaz, Kfir & Forges, Françoise, 2015. "Information disclosure to Cournot duopolists," Economics Letters, Elsevier, vol. 126(C), pages 167-170.
    13. Shlomit Hon‐Snir & Benyamin Shitovitz & Menahem Spiegel, 2010. "Bayesian Equilibrium in a Public Good Economy," Journal of Public Economic Theory, Association for Public Economic Theory, vol. 12(2), pages 387-398, April.
    14. Routledge, Robert R., 2010. "Bertrand competition with cost uncertainty," Economics Letters, Elsevier, vol. 107(3), pages 356-359, June.
    15. R. R. Routledge & R. A. Edwards, 2020. "Ambiguity and price competition," Theory and Decision, Springer, vol. 88(2), pages 231-256, March.
    16. Cabolis, C. & Manasakis, C. & Moreno, D. & Petrakis, E., 2021. "The interactions of R&D investments and horizontal mergers," Journal of Economic Behavior & Organization, Elsevier, vol. 187(C), pages 507-534.

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    More about this item

    Keywords

    Oligopoly; Incomplete Information; Bayesian; Cournot; Equilibrium; Existence; Uniqueness;
    All these keywords.

    JEL classification:

    • C72 - Mathematical and Quantitative Methods - - Game Theory and Bargaining Theory - - - Noncooperative Games
    • D43 - Microeconomics - - Market Structure, Pricing, and Design - - - Oligopoly and Other Forms of Market Imperfection
    • L13 - Industrial Organization - - Market Structure, Firm Strategy, and Market Performance - - - Oligopoly and Other Imperfect Markets

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