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Choice or competition: does integration benefit everyone?

Author

Listed:
  • Kamada, Yuichiro

    (Haas School of Business, University of California, Berkeley and Department of Economics, University of Tokyo)

  • Kojima, Fuhito

    (Department of Economics, University of Tokyo)

Abstract

Matching markets are often fragmented, organized at a small local level. While integration of matching markets may lead to welfare gains by expanding choice, it may also harm some market participants by increasing competition for the same resources. We show that every "good" mechanism fails the monotonicity requirement that no individuals be hurt by integration. Then we provide characterization results that identify conditions under which monotonicity becomes compatible with other desirable properties of matching mechanisms.

Suggested Citation

  • Kamada, Yuichiro & Kojima, Fuhito, 2026. "Choice or competition: does integration benefit everyone?," Theoretical Economics, Econometric Society, vol. 21(1), January.
    • Handle: RePEc:the:publsh:6468
    as

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    References listed on IDEAS

    as
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    Keywords

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    JEL classification:

    • C70 - Mathematical and Quantitative Methods - - Game Theory and Bargaining Theory - - - General
    • C78 - Mathematical and Quantitative Methods - - Game Theory and Bargaining Theory - - - Bargaining Theory; Matching Theory
    • D47 - Microeconomics - - Market Structure, Pricing, and Design - - - Market Design
    • D61 - Microeconomics - - Welfare Economics - - - Allocative Efficiency; Cost-Benefit Analysis
    • D63 - Microeconomics - - Welfare Economics - - - Equity, Justice, Inequality, and Other Normative Criteria and Measurement

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