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The Two Margin Problem in Insurance Markets

Author

Listed:
  • Geruso, Michael

    (University of Texas at Austin)

  • Layton, Timothy J.

    (Harvard University)

  • McCormack, Grace

    (Harvard University)

  • Shepard, Mark

    (Harvard Kennedy School)

Abstract

Insurance markets often feature consumer sorting along both an extensive margin (whether to buy) and an intensive margin (which plan to buy). We present a new graphical theoretical framework that extends a workhorse model to incorporate both selection margins simultaneously. A key insight from our framework is that policies aimed at addressing one margin of selection often involve an economically meaningful tradeoff on the other margin in terms of prices, enrollment,and welfare. Using data from Massachusetts, we illustrate these tradeoffs in an empirical sufficient statistics approach that is tightly linked to the graphical framework we develop.

Suggested Citation

  • Geruso, Michael & Layton, Timothy J. & McCormack, Grace & Shepard, Mark, 2019. "The Two Margin Problem in Insurance Markets," Working Paper Series rwp19-035, Harvard University, John F. Kennedy School of Government.
  • Handle: RePEc:ecl:harjfk:rwp19-035
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    References listed on IDEAS

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    More about this item

    JEL classification:

    • D82 - Microeconomics - - Information, Knowledge, and Uncertainty - - - Asymmetric and Private Information; Mechanism Design
    • G22 - Financial Economics - - Financial Institutions and Services - - - Insurance; Insurance Companies; Actuarial Studies
    • H51 - Public Economics - - National Government Expenditures and Related Policies - - - Government Expenditures and Health
    • I1 - Health, Education, and Welfare - - Health
    • I13 - Health, Education, and Welfare - - Health - - - Health Insurance, Public and Private

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