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Equilibrium existence in Krugman’s and Bertoletti–Etro’s trade models: the general case

Author

Listed:
  • Fedor Slepov

    (HSE University
    Pennsylvania State University)

  • Sergey Kokovin

    (HSE University)

Abstract

We revisit Krugman’s (J Int Econ 9(4):469–479, 1979.) classical trade model in its general form with several asymmetric countries and unspecified additive utility functions. We present the weakest known conditions on utilities sufficient for the existence of equilibrium. These conditions are also necessary under symmetric preferences. Using the same method for Bertoletti and Etro’s (Econ J 127(603):1217–1243, 2017.) trade model with several asymmetric countries, we establish sufficient conditions on unspecified indirect utilities for the existence of equilibrium.

Suggested Citation

  • Fedor Slepov & Sergey Kokovin, 2025. "Equilibrium existence in Krugman’s and Bertoletti–Etro’s trade models: the general case," Economic Theory, Springer;Society for the Advancement of Economic Theory (SAET), vol. 80(3), pages 761-800, November.
    • Handle: RePEc:spr:joecth:v:80:y:2025:i:3:d:10.1007_s00199-025-01642-8
    DOI: 10.1007/s00199-025-01642-8
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    References listed on IDEAS

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    1. Evgeny Zhelobodko & Sergey Kokovin & Mathieu Parenti & Jacques‐François Thisse, 2012. "Monopolistic Competition: Beyond the Constant Elasticity of Substitution," Econometrica, Econometric Society, vol. 80(6), pages 2765-2784, November.
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    JEL classification:

    • F12 - International Economics - - Trade - - - Models of Trade with Imperfect Competition and Scale Economies; Fragmentation
    • L13 - Industrial Organization - - Market Structure, Firm Strategy, and Market Performance - - - Oligopoly and Other Imperfect Markets
    • D43 - Microeconomics - - Market Structure, Pricing, and Design - - - Oligopoly and Other Forms of Market Imperfection

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