IDEAS home Printed from https://ideas.repec.org/p/nbr/nberwo/3430.html
   My bibliography  Save this paper

Measuring Ignorance in the Market: A New Method with an Application to Physician Services

Author

Listed:
  • Martin Gaynor
  • Solomon Polachek

Abstract

Ever since Stigler's seminal piece on the economics of information, a great deal of research has been done investigating equilibrium in markets with imperfect information. While most of this research has been concerned with theoretically establishing the conditions under which there exists a distribution of prices in equilibrium, there is a small, but growing, body of empirical research in this area. This work has followed the suggestion of Stigler and utilized the dispersion of prices (usually the variance) as a measure of ignorance about price. There are two disadvantages to using the variance (or another measure of dispersion, such as the range) of prices as a measure of ignorance about price. The first reason, recognized by Stigler and others, is that price can vary for many reasons other than ignorance. Thus dispersion is not a pure measure of ignorance about prices. The second reason, which has not been commonly considered in the empirical literature, is that price dispersion can due to ignorance on the part of both buyers and of sellers. In this paper we propose a method for measuring ignorance about price in a market which builds on Stigler's original suggestion to use dispersion as a measure of ignorance. The innovation is to use a new frontier estimation technique containing a three component error term to separate observed price dispersion into purely random variation, variation due to buyer ignorance, and variation due to seller ignorance . We apply the technique to the physicians' service market. This supplies us with quantitative indices of price ignorance for different services and how the level of ignorance varies by buyer, seller, and market area characteristics. The results are striking. Buyer ignorance exceeds seller ignorance by roughly a factor of two in his market, and this gap is greater for services which are less frequently purchased, more heavily insured, or accompanied by greater severity of illness, as predicted by search theory.

Suggested Citation

  • Martin Gaynor & Solomon Polachek, 1990. "Measuring Ignorance in the Market: A New Method with an Application to Physician Services," NBER Working Papers 3430, National Bureau of Economic Research, Inc.
    • Handle: RePEc:nbr:nberwo:3430
    Note: EH
    as

    Download full text from publisher

    File URL: http://www.nber.org/papers/w3430.pdf
    Download Restriction: no
    ---><---

    References listed on IDEAS

    as
    1. Roger Feldman & James W. Begun, 1978. "The Effects of Advertising Lessons from Optometry," NBER Chapters, in: The Economics of Physician and Patient Behavior, pages 247-262, National Bureau of Economic Research, Inc.
    2. Van Hoomissen, Theresa, 1988. "Price Dispersion and Inflation: Evidence from Israel," Journal of Political Economy, University of Chicago Press, vol. 96(6), pages 1303-1314, December.
    3. Goldman, Fred & Grossman, Michael, 1978. "The Demand for Pediatric Care: An Hedonic Approach," Journal of Political Economy, University of Chicago Press, vol. 86(2), pages 259-280, April.
    4. Dionne, Georges, 1984. "Search and Insurance," International Economic Review, Department of Economics, University of Pennsylvania and Osaka University Institute of Social and Economic Research Association, vol. 25(2), pages 357-367, June.
    5. Mathewson, G Frank, 1983. "Information, Search, and Price Variability of Individual Life Insurance Contracts," Journal of Industrial Economics, Wiley Blackwell, vol. 32(2), pages 131-148, December.
    6. Jarque, Carlos M. & Bera, Anil K., 1980. "Efficient tests for normality, homoscedasticity and serial independence of regression residuals," Economics Letters, Elsevier, vol. 6(3), pages 255-259.
    7. Polachek, Solomon W & Yoon, Bong Joon, 1987. "A Two-tiered Earnings Frontier Estimation of Employer and Employee Information in the Labor Market," The Review of Economics and Statistics, MIT Press, vol. 69(2), pages 296-302, May.
    8. MacKinnon, James G. & White, Halbert & Davidson, Russell, 1983. "Tests for model specification in the presence of alternative hypotheses : Some further results," Journal of Econometrics, Elsevier, vol. 21(1), pages 53-70, January.
    9. Benham, Lee, 1972. "The Effect of Advertising on the Price of Eyeglasses," Journal of Law and Economics, University of Chicago Press, vol. 15(2), pages 337-352, October.
    10. Kwoka, John E, Jr, 1984. "Advertising and the Price and Quality of Optometric Services," American Economic Review, American Economic Association, vol. 74(1), pages 211-216, March.
    11. repec:bla:scandj:v:79:y:1977:i:1:p:20-40 is not listed on IDEAS
    12. Marvel, Howard P, 1976. "The Economics of Information and Retail Gasoline Price Behavior: An Empirical Analysis," Journal of Political Economy, University of Chicago Press, vol. 84(5), pages 1033-1060, October.
    13. John W. Pratt & David A. Wise & Richard Zeckhauser, 1979. "Price Differences in almost Competitive Markets," The Quarterly Journal of Economics, President and Fellows of Harvard College, vol. 93(2), pages 189-211.
    14. Dahlby, Bev & West, Douglas S, 1986. "Price Dispersion in an Automobile Insurance Market," Journal of Political Economy, University of Chicago Press, vol. 94(2), pages 418-438, April.
    15. Burdett, Kenneth & Judd, Kenneth L, 1983. "Equilibrium Price Dispersion," Econometrica, Econometric Society, vol. 51(4), pages 955-969, July.
    16. Cox, Steven R & DeSerpa, Allan C & Canby, William C, Jr, 1982. "Consumer Information and the Pricing of Legal Services," Journal of Industrial Economics, Wiley Blackwell, vol. 30(3), pages 305-318, March.
    17. Mark V. Pauly & Mark A. Satterthwaite, 1981. "The Pricing of Primary Care Physicians' Services: A Test of the Role of Consumer Information," Bell Journal of Economics, The RAND Corporation, vol. 12(2), pages 488-506, Autumn.
    18. Marquis, M. Susan, 1985. "Cost-sharing and provider choice," Journal of Health Economics, Elsevier, vol. 4(2), pages 137-157, June.
    19. Cady, John F, 1976. "An Estimate of the Price Effects of Restrictions on Drug Price Advertising," Economic Inquiry, Western Economic Association International, vol. 14(4), pages 493-510, December.
    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. Martin Gaynor & Deborah Haas-Wilson, 1999. "Change, Consolidation, and Competition in Health Care Markets," Journal of Economic Perspectives, American Economic Association, vol. 13(1), pages 141-164, Winter.
    2. Paul Gertler & Roland Sturm & Bruce Davidson, 1994. "Information and the Demand for Supplemental Medicare Insurance," NBER Working Papers 4700, National Bureau of Economic Research, Inc.
    3. John Robst & Kimmarie Mcgoldrick, 1997. "Frontier estimation of changes in Workers' labor market information," Atlantic Economic Journal, Springer;International Atlantic Economic Society, vol. 25(4), pages 386-402, December.
    4. John Robst & Kimmarie McGOLDRICK, 1999. "The Measurement of Firm Information About Product Demand," Review of Industrial Organization, Springer;The Industrial Organization Society, vol. 15(2), pages 149-163, September.
    5. Solomon W. Polachek & Jun (Jeff) Xiang, 2006. "The Effects of Incomplete Employee Wage Information: A Cross-Country Analysis," Research in Labor Economics, in: The Economics of Immigration and Social Diversity, pages 35-75, Emerald Group Publishing Limited.
    6. Gaynor, Martin & Town, Robert J., 2011. "Competition in Health Care Markets," Handbook of Health Economics, in: Mark V. Pauly & Thomas G. Mcguire & Pedro P. Barros (ed.), Handbook of Health Economics, volume 2, chapter 0, pages 499-637, Elsevier.
    7. Darren Grant, 2005. "Information and sorting in the market for obstetrical services," Health Economics, John Wiley & Sons, Ltd., vol. 14(7), pages 703-719, July.

    Most related items

    These are the items that most often cite the same works as this one and are cited by the same works as this one.
    1. Martin Gaynor, 1994. "Issues in the Industrial Organization of the Market for Physician Services," Journal of Economics & Management Strategy, Wiley Blackwell, vol. 3(1), pages 211-255, March.
    2. Jeffrey R. Brown & Austan Goolsbee, 2002. "Does the Internet Make Markets More Competitive? Evidence from the Life Insurance Industry," Journal of Political Economy, University of Chicago Press, vol. 110(3), pages 481-507, June.
    3. Mariano Tommasi, 1992. "Inflation and Relative Prices Evidence from Argentina," UCLA Economics Working Papers 661, UCLA Department of Economics.
    4. Barron, John M. & Taylor, Beck A. & Umbeck, John R., 2004. "Number of sellers, average prices, and price dispersion," International Journal of Industrial Organization, Elsevier, vol. 22(8-9), pages 1041-1066, November.
    5. Joshua Sherman & Avi Weiss, 2017. "On Fruitful And Futile Tests Of The Relationship Between Search And Price Dispersion," Economic Inquiry, Western Economic Association International, vol. 55(4), pages 1898-1918, October.
    6. Jason R. Blevins & Garrett T. Senney, 2019. "Dynamic selection and distributional bounds on search costs in dynamic unit‐demand models," Quantitative Economics, Econometric Society, vol. 10(3), pages 891-929, July.
    7. Alfredo Martín-Oliver & Vicente Salas-Fumás & Jesús Saurina, 2005. "Interest rate dispersion in deposit and loan markets," Working Papers 0506, Banco de España.
    8. Alfredo Martin-Oliver & Vicente Salas-Fumas & Jesús Saurina, 2008. "Search Cost and Price Dispersion in Vertically Related Markets: The Case of Bank Loans and Deposits," Review of Industrial Organization, Springer;The Industrial Organization Society, vol. 33(4), pages 297-323, December.
    9. Jeffrey R. Brown & Austan Goolsbee, 2000. "Does the Internet Make Markets More Competitive?," NBER Working Papers 7996, National Bureau of Economic Research, Inc.
    10. Joel Waldfogel & Jeffrey Milyo, 1999. "The Effect of Price Advertising on Prices: Evidence in the Wake of 44 Liquormart," American Economic Review, American Economic Association, vol. 89(5), pages 1081-1096, December.
    11. Louis De Alessi, 1989. "The Effect of Institutions on the Choices of Consumers and Providers of Health Care," Journal of Theoretical Politics, , vol. 1(4), pages 427-458, October.
    12. Mitchell Berlin & Loretta J. Mester, 2004. "Credit card rates and consumer search," Review of Financial Economics, John Wiley & Sons, vol. 13(1-2), pages 179-198.
    13. Marshall Reinsdorf, 1993. "The Effect of Outlet Price Differentials on the US Consumer Price Index," NBER Chapters, in: Price Measurements and Their Uses, pages 227-258, National Bureau of Economic Research, Inc.
    14. Erik Brynjolfsson & Michael D. Smith, 2000. "Frictionless Commerce? A Comparison of Internet and Conventional Retailers," Management Science, INFORMS, vol. 46(4), pages 563-585, April.
    15. Solomon W. Polachek & Jun (Jeff) Xiang, 2006. "The Effects of Incomplete Employee Wage Information: A Cross-Country Analysis," Research in Labor Economics, in: The Economics of Immigration and Social Diversity, pages 35-75, Emerald Group Publishing Limited.
    16. Greg Kaplan & Guido Menzio & Leena Rudanko & Nicholas Trachter, 2019. "Relative Price Dispersion: Evidence and Theory," American Economic Journal: Microeconomics, American Economic Association, vol. 11(3), pages 68-124, August.
    17. George Alessandria, 2005. "Consumer search, price dispersion, and international relative price volatility," Working Papers 05-9, Federal Reserve Bank of Philadelphia.
    18. J. Rupert Gatti, 2000. "Equilibrium Price Dispersion with Sequential Search," Econometric Society World Congress 2000 Contributed Papers 1368, Econometric Society.
    19. Mark J. Roberts & Dylan Supina, 1997. "Output Price and Markup Dispersion in Micro Data: The Roles of Producer Heterogeneity and Noise," NBER Working Papers 6075, National Bureau of Economic Research, Inc.
    20. Cason, Timothy N. & Friedman, Daniel, 2003. "Buyer search and price dispersion: a laboratory study," Journal of Economic Theory, Elsevier, vol. 112(2), pages 232-260, October.

    More about this item

    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:nbr:nberwo:3430. See general information about how to correct material in RePEc.

    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 bibliographic 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.

    For technical questions regarding this item, or to correct its authors, title, abstract, bibliographic or download information, contact: the person in charge (email available below). General contact details of provider: https://edirc.repec.org/data/nberrus.html .

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

    IDEAS is a RePEc service. RePEc uses bibliographic data supplied by the respective publishers.