IDEAS home Printed from https://ideas.repec.org/a/eee/econom/v190y2016i1p62-78.html
   My bibliography  Save this article

Adverse selection, moral hazard and the demand for Medigap insurance

Author

Listed:
  • Keane, Michael
  • Stavrunova, Olena

Abstract

In this paper we study the adverse selection and moral hazard effects of Medicare supplemental insurance (Medigap). While both have been studied separately, this is the first paper to analyze them in a unified econometric framework. We find that adverse selection into Medigap is weak, but the moral hazard effect is substantial. On average, Medigap coverage increases health care spending by 24%, with especially large effects for relatively healthy individuals. These results have important policy implications. For instance, they imply that conventional remedies for inefficiencies created by adverse selection (e.g., mandatory enrollment) may lead to substantial health care cost increases.

Suggested Citation

  • Keane, Michael & Stavrunova, Olena, 2016. "Adverse selection, moral hazard and the demand for Medigap insurance," Journal of Econometrics, Elsevier, vol. 190(1), pages 62-78.
  • Handle: RePEc:eee:econom:v:190:y:2016:i:1:p:62-78
    DOI: 10.1016/j.jeconom.2015.08.002
    as

    Download full text from publisher

    File URL: http://www.sciencedirect.com/science/article/pii/S0304407615002225
    Download Restriction: Full text for ScienceDirect subscribers only

    As the access to this document is restricted, you may want to look for a different version below or search for a different version of it.

    Other versions of this item:

    References listed on IDEAS

    as
    1. Gilleskie, Donna B. & Mroz, Thomas A., 2004. "A flexible approach for estimating the effects of covariates on health expenditures," Journal of Health Economics, Elsevier, vol. 23(2), pages 391-418, March.
    2. Tomas Philipson & John Cawley, 1999. "An Empirical Examination of Information Barriers to Trade in Insurance," American Economic Review, American Economic Association, vol. 89(4), pages 827-846, September.
    3. Chiappori, Pierre-Andre & Durand, Franck & Geoffard, Pierre-Yves, 1998. "Moral hazard and the demand for physician services: First lessons from a French natural experiment," European Economic Review, Elsevier, vol. 42(3-5), pages 499-511, May.
    4. Geweke, John, 2007. "Interpretation and inference in mixture models: Simple MCMC works," Computational Statistics & Data Analysis, Elsevier, vol. 51(7), pages 3529-3550, April.
    5. Wolfe, John R. & Goddeeris, John H., 1991. "Adverse selection, moral hazard, and wealth effects in the medigap insurance market," Journal of Health Economics, Elsevier, vol. 10(4), pages 433-459.
    6. John F. Geweke, 1991. "Evaluating the accuracy of sampling-based approaches to the calculation of posterior moments," Staff Report 148, Federal Reserve Bank of Minneapolis.
    7. Michael Rothschild & Joseph Stiglitz, 1976. "Equilibrium in Competitive Insurance Markets: An Essay on the Economics of Imperfect Information," The Quarterly Journal of Economics, Oxford University Press, vol. 90(4), pages 629-649.
    8. Munkin M & Trivedi P. K, 2009. "Incentives and Selection Effects of Drug Coverage on Total Drug Expenditure: a Finite Mixture Approach," Health, Econometrics and Data Group (HEDG) Working Papers 09/22, HEDG, c/o Department of Economics, University of York.
    9. John Geweke, 2004. "Getting It Right: Joint Distribution Tests of Posterior Simulators," Journal of the American Statistical Association, American Statistical Association, vol. 99, pages 799-804, January.
    10. Manning, Willard G., 1998. "The logged dependent variable, heteroscedasticity, and the retransformation problem," Journal of Health Economics, Elsevier, vol. 17(3), pages 283-295, June.
    11. Manning, Willard G, et al, 1987. "Health Insurance and the Demand for Medical Care: Evidence from a Randomized Experiment," American Economic Review, American Economic Association, vol. 77(3), pages 251-277, June.
    12. Hanming Fang & Lauren Nicholas & Daniel Silverman, 2010. "Cognitive Ability and Retiree Health Care Expenditure," Working Papers wp230, University of Michigan, Michigan Retirement Research Center.
    13. Mullahy, John, 1998. "Much ado about two: reconsidering retransformation and the two-part model in health econometrics," Journal of Health Economics, Elsevier, vol. 17(3), pages 247-281, June.
    14. Murat K. Munkin & Partha Deb & Pravin K. Trivedi, 2006. "Bayesian analysis of the two-part model with endogeneity: application to health care expenditure," Journal of Applied Econometrics, John Wiley & Sons, Ltd., vol. 21(7), pages 1081-1099.
    15. Buchmueller, Thomas, 2006. "Price and the health plan choices of retirees," Journal of Health Economics, Elsevier, vol. 25(1), pages 81-101, January.
    16. Ahmed W. Khwaja, 2001. "Health Insurance, Habits and Health Outcomes: A Dynamic Stochastic Model of Investment in Health," Computing in Economics and Finance 2001 166, Society for Computational Economics.
    17. Alma Cohen & Peter Siegelman, 2010. "Testing for Adverse Selection in Insurance Markets," Journal of Risk & Insurance, The American Risk and Insurance Association, vol. 77(1), pages 39-84.
    18. Kimball, Miles S & Sahm, Claudia R & Shapiro, Matthew D, 2008. "Imputing Risk Tolerance From Survey Responses," Journal of the American Statistical Association, American Statistical Association, vol. 103(483), pages 1028-1038.
    19. Rubin, Donald B, 1986. "Statistical Matching Using File Concatenation with Adjusted Weights and Multiple Imputations," Journal of Business & Economic Statistics, American Statistical Association, vol. 4(1), pages 87-94, January.
    20. de Meza, David & Webb, David C, 2001. "Advantageous Selection in Insurance Markets," RAND Journal of Economics, The RAND Corporation, vol. 32(2), pages 249-262, Summer.
    21. Pierre-Andre Chiappori & Bernard Salanie, 2000. "Testing for Asymmetric Information in Insurance Markets," Journal of Political Economy, University of Chicago Press, vol. 108(1), pages 56-78, February.
    22. Hanming Fang & Michael P. Keane & Dan Silverman, 2008. "Sources of Advantageous Selection: Evidence from the Medigap Insurance Market," Journal of Political Economy, University of Chicago Press, vol. 116(2), pages 303-350, April.
    23. Deb, Partha & Munkin, Murat K. & Trivedi, Pravin K., 2006. "Private Insurance, Selection, and Health Care Use: A Bayesian Analysis of a Roy-Type Model," Journal of Business & Economic Statistics, American Statistical Association, vol. 24, pages 403-415, October.
    24. Munkin, Murat K. & Trivedi, Pravin K., 2008. "Bayesian analysis of the ordered probit model with endogenous selection," Journal of Econometrics, Elsevier, vol. 143(2), pages 334-348, April.
    25. Manning, Willard G. & Basu, Anirban & Mullahy, John, 2005. "Generalized modeling approaches to risk adjustment of skewed outcomes data," Journal of Health Economics, Elsevier, vol. 24(3), pages 465-488, May.
    26. Michael Keane & Olena Stavrunova, 2011. "A smooth mixture of Tobits model for healthcare expenditure," Health Economics, John Wiley & Sons, Ltd., vol. 20(9), pages 1126-1153, September.
    27. Alma Cohen, 2005. "Asymmetric Information and Learning: Evidence from the Automobile Insurance Market," The Review of Economics and Statistics, MIT Press, vol. 87(2), pages 197-207, May.
    28. Murat K. Munkin & Pravin K. Trivedi, 2010. "Disentangling incentives effects of insurance coverage from adverse selection in the case of drug expenditure: a finite mixture approach," Health Economics, John Wiley & Sons, Ltd., vol. 19(9), pages 1093-1108, September.
    29. Dardanoni, Valentino & Li Donni, Paolo, 2012. "Incentive and selection effects of Medigap insurance on inpatient care," Journal of Health Economics, Elsevier, vol. 31(3), pages 457-470.
    30. Fruhwirth-Schnatter S., 2001. "Markov Chain Monte Carlo Estimation of Classical and Dynamic Switching and Mixture Models," Journal of the American Statistical Association, American Statistical Association, vol. 96, pages 194-209, March.
    31. Geweke, John & Keane, Michael, 2007. "Smoothly mixing regressions," Journal of Econometrics, Elsevier, vol. 138(1), pages 252-290, May.
    32. Ettner, Susan L., 1997. "Adverse selection and the purchase of Medigap insurance by the elderly," Journal of Health Economics, Elsevier, vol. 16(5), pages 543-562, October.
    33. Hurd, Michael D. & McGarry, Kathleen, 1997. "Medical insurance and the use of health care services by the elderly," Journal of Health Economics, Elsevier, vol. 16(2), pages 129-154, April.
    34. Blough, David K. & Madden, Carolyn W. & Hornbrook, Mark C., 1999. "Modeling risk using generalized linear models," Journal of Health Economics, Elsevier, vol. 18(2), pages 153-171, April.
    35. Patrick Bajari & Christina Dalton & Han Hong & Ahmed Khwaja, 2014. "Moral hazard, adverse selection, and health expenditures: A semiparametric analysis," RAND Journal of Economics, RAND Corporation, vol. 45(4), pages 747-763, December.
    36. Amy Finkelstein & Kathleen McGarry, 2006. "Multiple Dimensions of Private Information: Evidence from the Long-Term Care Insurance Market," American Economic Review, American Economic Association, vol. 96(4), pages 938-958, September.
    37. Manning, Willard G. & Mullahy, John, 2001. "Estimating log models: to transform or not to transform?," Journal of Health Economics, Elsevier, vol. 20(4), pages 461-494, July.
    38. Harris, Katherine M. & Keane, Michael P., 1998. "A model of health plan choice:: Inferring preferences and perceptions from a combination of revealed preference and attitudinal data," Journal of Econometrics, Elsevier, vol. 89(1-2), pages 131-157, November.
    39. Gruber, Jonathan & Washington, Ebonya, 2005. "Subsidies to employee health insurance premiums and the health insurance market," Journal of Health Economics, Elsevier, vol. 24(2), pages 253-276, March.
    40. Buntin, Melinda Beeuwkes & Zaslavsky, Alan M., 2004. "Too much ado about two-part models and transformation?: Comparing methods of modeling Medicare expenditures," Journal of Health Economics, Elsevier, vol. 23(3), pages 525-542, May.
    41. Cardon, James H & Hendel, Igal, 2001. "Asymmetric Information in Health Insurance: Evidence from the National Medical Expenditure Survey," RAND Journal of Economics, The RAND Corporation, vol. 32(3), pages 408-427, Autumn.
    42. Chib, Siddhartha, 1992. "Bayes inference in the Tobit censored regression model," Journal of Econometrics, Elsevier, vol. 51(1-2), pages 79-99.
    Full references (including those not matched with items on IDEAS)

    Citations

    Citations are extracted by the CitEc Project, subscribe to its RSS feed for this item.
    as


    Cited by:

    1. Vincenzo Atella & Alberto Holly & Alessandro Mistretta, 2016. "Disentangling Adverse Selection, Moral Hazard and Supply Induced Demand: An Empirical Analysis of The Demand For Healthcare Services," CEIS Research Paper 389, Tor Vergata University, CEIS, revised 28 Jun 2016.
    2. Woldemichael, Andinet & Gurara, Daniel Zerfu & Shimeles, Abebe, 2016. "Community-Based Health Insurance and Out-of-Pocket Healthcare Spending in Africa: Evidence from Rwanda," IZA Discussion Papers 9922, Institute for the Study of Labor (IZA).
    3. Julie L. Hotchkiss & Anil Rupasingha, 2016. "Wage Determination in Social Occupations: the Role of Individual Social Capital," Working Papers 16-46, Center for Economic Studies, U.S. Census Bureau.
    4. Michael Keane & Olena Stavrunova, 2011. "A smooth mixture of Tobits model for healthcare expenditure," Health Economics, John Wiley & Sons, Ltd., vol. 20(9), pages 1126-1153, September.
    5. repec:taf:oaefxx:v:5:y:2017:i:1:p:1330303 is not listed on IDEAS
    6. Mercy Raquel Orellana Bravo & Juan Andrés Piedra Peña & Luis Santiago Sarmiento Moscoso, 2017. "Evidence About The Moral Hazard In The Ecuadorian Health System," Journal of Smart Economic Growth, , vol. 2(1), pages 109-132, March.
    7. Julie L. Hotchkiss, 2017. "Decennial Census Return Rates: The Role of Social Capital," Working Papers 17-39, Center for Economic Studies, U.S. Census Bureau.
    8. Stephen Kwasi Opoku Duku & Francis Asenso-Boadi & Edward Nketiah-Amponsah & Daniel Kojo Arhinful, 2016. "Utilization of healthcare services and renewal of health insurance membership: evidence of adverse selection in Ghana," Health Economics Review, Springer, vol. 6(1), pages 1-12, December.

    More about this item

    Keywords

    Health insurance; Health expenditures; Adverse selection; Moral hazard; Medicare; Medigap; Bayesian analysis; Missing data; Data fusion; Markov-chain Monte Carlo; Gibbs; Metropolis; Simultaneous equation model;

    JEL classification:

    • C11 - Mathematical and Quantitative Methods - - Econometric and Statistical Methods and Methodology: General - - - Bayesian Analysis: General
    • C15 - Mathematical and Quantitative Methods - - Econometric and Statistical Methods and Methodology: General - - - Statistical Simulation Methods: General
    • C30 - Mathematical and Quantitative Methods - - Multiple or Simultaneous Equation Models; Multiple Variables - - - General
    • C63 - Mathematical and Quantitative Methods - - Mathematical Methods; Programming Models; Mathematical and Simulation Modeling - - - Computational Techniques
    • D82 - Microeconomics - - Information, Knowledge, and Uncertainty - - - Asymmetric and Private Information; Mechanism Design
    • I11 - Health, Education, and Welfare - - Health - - - Analysis of Health Care Markets
    • I13 - Health, Education, and Welfare - - Health - - - Health Insurance, Public and Private

    Statistics

    Access and download statistics

    Corrections

    All material on this site has been provided by the respective publishers and authors. You can help correct errors and omissions. When requesting a correction, please mention this item's handle: RePEc:eee:econom:v:190:y:2016:i:1:p:62-78. See general information about how to correct material in RePEc.

    For technical questions regarding this item, or to correct its authors, title, abstract, bibliographic or download information, contact: (Dana Niculescu). General contact details of provider: http://www.elsevier.com/locate/jeconom .

    If you have authored this item and are not yet registered with RePEc, we encourage you to do it here. This allows to link your profile to this item. It also allows you to accept potential citations to this item that we are uncertain about.

    If CitEc recognized a reference but did not link an item in RePEc to it, you can help with this form .

    If you know of missing items citing this one, you can help us creating those links by adding the relevant references in the same way as above, for each refering item. If you are a registered author of this item, you may also want to check the "citations" tab in your RePEc Author Service profile, as there may be some citations waiting for confirmation.

    Please note that corrections may take a couple of weeks to filter through the various RePEc services.

    IDEAS is a RePEc service hosted by the Research Division of the Federal Reserve Bank of St. Louis . RePEc uses bibliographic data supplied by the respective publishers.