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On the (non-)lattice structure of the equilibrium set in games with strategic substitutes

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  • Sunanda Roy

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  • Tarun Sabarwal

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Abstract

This paper studies models where the optimal response functions under consideration are non-increasing in endogenous variables, and weakly increasing in exogenous parameters. Such models include games with strategic substitutes, and include cases where additionally, some variables may be strategic complements. The main result here is that the equilibrium set in such models is a non-empty, complete lattice, if, and only if, there is a unique equilibrium. Indeed, for a given parameter value, a pair of distinct equilibria are never comparable. Therefore, with multiple equilibria, some of the established techniques for exhibiting increasing equilibria or computing equilibria that use the largest or smallest equilibrium, or that use the lattice structure of the equilibrium set do not apply to such models. Moreover, there are no ranked equilibria in such models. Additionally, the analysis here implies a new proof and a slight generalization of some existing results. It is shown that when a parameter increases, no new equilibrium is smaller than any old equilibrium. (In particular, in n-player games of strategic substitutes with real-valued action spaces, symmetric equilibria increase with the parameter.)
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  • Sunanda Roy & Tarun Sabarwal, 2008. "On the (non-)lattice structure of the equilibrium set in games with strategic substitutes," Economic Theory, Springer;Society for the Advancement of Economic Theory (SAET), vol. 37(1), pages 161-169, October.
  • Handle: RePEc:spr:joecth:v:37:y:2008:i:1:p:161-169 DOI: 10.1007/s00199-007-0285-9
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    References listed on IDEAS

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    1. Federico Echenique, 2002. "Comparative Statics by Adaptive Dynamics and the Correspondence Principle," Econometrica, Econometric Society, vol. 70(2), pages 833-844, March.
    2. Zhou Lin, 1994. "The Set of Nash Equilibria of a Supermodular Game Is a Complete Lattice," Games and Economic Behavior, Elsevier, vol. 7(2), pages 295-300, September.
    3. Shannon, Chris, 1995. "Weak and Strong Monotone Comparative Statics," Economic Theory, Springer;Society for the Advancement of Economic Theory (SAET), pages 209-227.
    4. Dubey, Pradeep & Haimanko, Ori & Zapechelnyuk, Andriy, 2006. "Strategic complements and substitutes, and potential games," Games and Economic Behavior, Elsevier, vol. 54(1), pages 77-94, January.
    5. Katherine M. O'Regan & John M. Quigley, 1996. "Teenage Employment and the Spatial Isolation of Minority and Poverty Households," Journal of Human Resources, University of Wisconsin Press, pages 692-702.
    6. Echenique, Federico & Sabarwal, Tarun, 2003. "Strong comparative statics of equilibria," Games and Economic Behavior, Elsevier, vol. 42(2), pages 307-314, February.
    7. Bulow, Jeremy I & Geanakoplos, John D & Klemperer, Paul D, 1985. "Multimarket Oligopoly: Strategic Substitutes and Complements," Journal of Political Economy, University of Chicago Press, vol. 93(3), pages 488-511, June.
    8. Milgrom, Paul & Roberts, John, 1994. "Comparing Equilibria," American Economic Review, American Economic Association, pages 441-459.
    9. Federico Echenique, 2003. "Mixed equilibria in games of strategic complementarities," Economic Theory, Springer;Society for the Advancement of Economic Theory (SAET), pages 33-44.
    10. Milgrom, Paul & Shannon, Chris, 1994. "Monotone Comparative Statics," Econometrica, Econometric Society, vol. 62(1), pages 157-180, January.
    11. Villas-Boas, J. Miguel, 1997. "Comparative Statics of Fixed Points," Journal of Economic Theory, Elsevier, vol. 73(1), pages 183-198, March.
    12. Edlin, Aaron S. & Shannon, Chris, 1998. "Strict Monotonicity in Comparative Statics," Journal of Economic Theory, Elsevier, vol. 81(1), pages 201-219, July.
    13. Lippman, Steven A. & Mamer, John W. & McCardle, Kevin F., 1987. "Comparative statics in non-cooperative games via transfinitely iterated play," Journal of Economic Theory, Elsevier, vol. 41(2), pages 288-303, April.
    14. Corchon, Luis C., 1994. "Comparative statics for aggregative games the strong concavity case," Mathematical Social Sciences, Elsevier, vol. 28(3), pages 151-165, December.
    15. Vives, Xavier, 1990. "Nash equilibrium with strategic complementarities," Journal of Mathematical Economics, Elsevier, vol. 19(3), pages 305-321.
    16. Milgrom, Paul & Roberts, John, 1990. "Rationalizability, Learning, and Equilibrium in Games with Strategic Complementarities," Econometrica, Econometric Society, vol. 58(6), pages 1255-1277, November.
    17. Federico Echenique, 2003. "The equilibrium set of two-player games with complementarities is a sublattice," Economic Theory, Springer;Society for the Advancement of Economic Theory (SAET), pages 903-905.
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    Citations

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    Cited by:

    1. Federico Quartieri & Ryusuke Shinohara, 2015. "Coalition-proofness in a class of games with strategic substitutes," International Journal of Game Theory, Springer;Game Theory Society, vol. 44(4), pages 785-813, November.
    2. Roy, Sunanda & Sabarwal, Tarun, 2012. "Characterizing stability properties in games with strategic substitutes," Games and Economic Behavior, Elsevier, vol. 75(1), pages 337-353.
    3. Finn Christensen, 2016. "Comparative Statics and Heterogeneity," Working Papers 2016-01, Towson University, Department of Economics, revised Oct 2016.
    4. Shuoxun Zhang & Tarun Sabarwal & Li Gan, 2015. "Strategic Or Nonstrategic: The Role Of Financial Benefit In Bankruptcy," Economic Inquiry, Western Economic Association International, vol. 53(2), pages 1004-1018, April.
    5. Andrew Monaco & Tarun Sabarwal, 2012. "Games with Strategic Heterogeneity," WORKING PAPERS SERIES IN THEORETICAL AND APPLIED ECONOMICS 201240, University of Kansas, Department of Economics, revised Nov 2012.
    6. Roy, Sunanda & Sabarwal, Tarun, 2010. "Monotone comparative statics for games with strategic substitutes," Journal of Mathematical Economics, Elsevier, vol. 46(5), pages 793-806, September.
    7. repec:kan:wpaper:201502 is not listed on IDEAS
    8. Maria Montero & Alex Possajennikov & Martin Sefton & Theodore Turocy, 2016. "Majoritarian Blotto contests with asymmetric battlefields: an experiment on apex games," Economic Theory, Springer;Society for the Advancement of Economic Theory (SAET), pages 55-89.
    9. Aflaki, Sam, 2013. "The effect of environmental uncertainty on the tragedy of the commons," Games and Economic Behavior, Elsevier, vol. 82(C), pages 240-253.
    10. repec:kan:wpaper:201412 is not listed on IDEAS
    11. Bertrand Koebel & François Laisney, 2014. "Aggregation with Cournot Competition: the Le Chatelier Samuelson Principle," Annals of Economics and Statistics, GENES, issue 115-116, pages 343-360.
    12. Andrew J. Monaco & Tarun Sabarwal, 2016. "Games with strategic complements and substitutes," Economic Theory, Springer;Society for the Advancement of Economic Theory (SAET), pages 65-91.
    13. Anne-Christine Barthel & Tarun Sabarwal, 2016. "Directional Monotone Comparative Statics," WORKING PAPERS SERIES IN THEORETICAL AND APPLIED ECONOMICS 201601, University of Kansas, Department of Economics.

    More about this item

    Keywords

    Monotone comparative statics; Non-increasing functions; Never increasing correspondences; Strategic substitutes; Equilibrium set; C60; C61; C62; C72;

    JEL classification:

    • C61 - Mathematical and Quantitative Methods - - Mathematical Methods; Programming Models; Mathematical and Simulation Modeling - - - Optimization Techniques; Programming Models; Dynamic Analysis
    • C72 - Mathematical and Quantitative Methods - - Game Theory and Bargaining Theory - - - Noncooperative Games
    • C62 - Mathematical and Quantitative Methods - - Mathematical Methods; Programming Models; Mathematical and Simulation Modeling - - - Existence and Stability Conditions of Equilibrium
    • C60 - Mathematical and Quantitative Methods - - Mathematical Methods; Programming Models; Mathematical and Simulation Modeling - - - General

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