IDEAS home Printed from https://ideas.repec.org/
MyIDEAS: Login to save this paper

Keynes Meets Markowitz: The Trade-off Between Familiarity and Diversification

  • Boyle, Phelim
  • Garlappi, Lorenzo
  • Uppal, Raman
  • Wang, Tan

We develop a model of portfolio choice to nest the views of Keynes - who advocates concentration in a few familiar assets - and Markowitz - who advocates diversification across assets. We rely on the concepts of ambiguity and ambiguity aversion to formalize the idea of an investor’s "familiarity" toward assets. The model shows that when an investor is equally ambiguous about all assets, then the optimal portfolio corresponds to Markowitz’s fully diversified portfolio. In contrast, when an investor exhibits different degrees of familiarity across assets, the optimal portfolio depends on (i) the relative degree of ambiguity across assets, and (ii) the standard deviation of the estimate of expected return on each asset. If the standard deviation of the expected return estimate and the difference between the ambiguity about familiar and unfamiliar assets are low, then the optimal portfolio is composed of a mix of both familiar and unfamiliar assets; moreover, an increase in correlation between assets causes an investor to increase concentration in the assets with which they are familiar (flight to familiarity). Alternatively, if the standard deviation of the expected return estimate and the difference between the ambiguity of familiar and unfamiliar assets are high, then the optimal portfolio contains only the familiar asset(s) as Keynes would have advocated. In the extreme case in which the ambiguity about all assets and the standard deviation of the estimated mean are high, then no risky asset is held (non-participation). The model also has empirically testable implications for trading behavior: in response to a change in idiosyncratic volatility, the Keynesian portfolio always exhibits more trading than the Markowitz portfolio, while the opposite is true for a change in systematic volatility. In the equilibrium version of the model with heterogeneous investors who are familiar with different assets, we find that the risk premium of stocks depends on both systematic and idiosyncratic volatility, and that the equity risk premium is significantly higher than in the standard model without ambiguity.

If you experience problems downloading a file, check if you have the proper application to view it first. In case of further problems read the IDEAS help page. Note that these files are not on the IDEAS site. Please be patient as the files may be large.

File URL: http://www.cepr.org/active/publications/discussion_papers/dp.php?dpno=7687
Download Restriction: CEPR Discussion Papers are free to download for our researchers, subscribers and members. If you fall into one of these categories but have trouble downloading our papers, please contact us at subscribers@cepr.org

As the access to this document is restricted, you may want to look for a different version under "Related research" (further below) or search for a different version of it.

Paper provided by C.E.P.R. Discussion Papers in its series CEPR Discussion Papers with number 7687.

as
in new window

Length:
Date of creation: Feb 2010
Date of revision:
Handle: RePEc:cpr:ceprdp:7687
Contact details of provider: Postal:
Centre for Economic Policy Research, 77 Bastwick Street, London EC1V 3PZ.

Phone: 44 - 20 - 7183 8801
Fax: 44 - 20 - 7183 8820

Order Information: Email:


References listed on IDEAS
Please report citation or reference errors to , or , if you are the registered author of the cited work, log in to your RePEc Author Service profile, click on "citations" and make appropriate adjustments.:

as in new window
  1. Brennan, M. J., 1975. "The Optimal Number of Securities in a Risky Asset Portfolio When There Are Fixed Costs of Transacting: Theory and Some Empirical Results," Journal of Financial and Quantitative Analysis, Cambridge University Press, vol. 10(03), pages 483-496, September.
  2. Valery Polkovnichenko, 2005. "Household Portfolio Diversification: A Case for Rank-Dependent Preferences," Review of Financial Studies, Society for Financial Studies, vol. 18(4), pages 1467-1502.
  3. Stijn Van Nieuwerburgh & Laura Veldkamp, 2006. "Inside Information and the Own Company Stock Puzzle," Journal of the European Economic Association, MIT Press, vol. 4(2-3), pages 623-633, 04-05.
  4. Kelly, Morgan, 1995. "All their eggs in one basket: Portfolio diversification of US households," Journal of Economic Behavior & Organization, Elsevier, vol. 27(1), pages 87-96, June.
  5. Peter Bossaerts & Paolo Ghirardato & Serena Guarnaschelli & William R. Zame, 2010. "Ambiguity in Asset Markets: Theory and Experiment," Review of Financial Studies, Society for Financial Studies, vol. 23(4), pages 1325-1359, April.
  6. Conine, Thomas E, Jr & Tamarkin, Maurry, J, 1981. "On Diversification Given Asymmetry in Returns," Journal of Finance, American Finance Association, vol. 36(5), pages 1143-55, December.
  7. Campbell, John, 2006. "Household Finance," Scholarly Articles 3157877, Harvard University Department of Economics.
  8. Kraus, Alan & Litzenberger, Robert H, 1976. "Skewness Preference and the Valuation of Risk Assets," Journal of Finance, American Finance Association, vol. 31(4), pages 1085-1100, September.
  9. Terrance Odean, 1999. "Do Investors Trade Too Much?," American Economic Review, American Economic Association, vol. 89(5), pages 1279-1298, December.
  10. Ju, Nengjiu & Miao, Jianjun, 2009. "Ambiguity, Learning, and Asset Returns," MPRA Paper 14737, University Library of Munich, Germany, revised Apr 2009.
  11. Garlappi, Lorenzo & Uppal, Raman & Wang, Tan, 2005. "Portfolio Selection with Parameter and Model Uncertainty: A Multi-Prior Approach," CEPR Discussion Papers 5148, C.E.P.R. Discussion Papers.
  12. Lasse Heje Pederson & Markus K Brunnermeier, 2007. "Market Liquidity and Funding Liquidity," FMG Discussion Papers dp580, Financial Markets Group.
  13. Blume, Marshall E & Friend, Irwin, 1975. "The Asset Structure of Individual Portfolios and Some Implications for Utility Functions," Journal of Finance, American Finance Association, vol. 30(2), pages 585-603, May.
  14. Robert C. Merton, 1980. "On Estimating the Expected Return on the Market: An Exploratory Investigation," NBER Working Papers 0444, National Bureau of Economic Research, Inc.
  15. Laurent E. Calvet & John Y. Campbell & Paolo Sodini, 2007. "Down or Out: Assessing the Welfare Costs of Household Investment Mistakes," Journal of Political Economy, University of Chicago Press, vol. 115(5), pages 707-747, October.
  16. French, Kenneth R. & Poterba, James M., 1990. "Japanese and U.S. cross-border common stock investments," Journal of the Japanese and International Economies, Elsevier, vol. 4(4), pages 476-493, December.
  17. Bryan R. Routledge & Stanley E. Zin, 2000. "Model Uncertainty and Liquidity," Econometric Society World Congress 2000 Contributed Papers 1617, Econometric Society.
  18. Welch, Ivo, 2000. "Views of Financial Economists on the Equity Premium and on Professional Controversies," The Journal of Business, University of Chicago Press, vol. 73(4), pages 501-37, October.
  19. Chan, Louis K C & Karceski, Jason & Lakonishok, Josef, 1999. "On Portfolio Optimization: Forecasting Covariances and Choosing the Risk Model," Review of Financial Studies, Society for Financial Studies, vol. 12(5), pages 937-74.
  20. Hui Chen & Nengjiu Ju & Jianjun Miao, . "Dynamic Asset Allocation with Ambiguous Return Predictability," Boston University - Department of Economics - Working Papers Series wp2009-015, Boston University - Department of Economics.
  21. LeRoy, Stephen F & Singell, Larry D, Jr, 1987. "Knight on Risk and Uncertainty," Journal of Political Economy, University of Chicago Press, vol. 95(2), pages 394-406, April.
  22. Massa, Massimo & Simonov, Andrei, 2004. "Hedging, Familiarity and Portfolio Choice," SIFR Research Report Series 21, Institute for Financial Research.
  23. Dimitri Vayanos, 2004. "Flight to quality, flight to liquidity, and the pricing of risk," LSE Research Online Documents on Economics 456, London School of Economics and Political Science, LSE Library.
  24. Mehra, Rajnish & Prescott, Edward C., 1985. "The equity premium: A puzzle," Journal of Monetary Economics, Elsevier, vol. 15(2), pages 145-161, March.
  25. Cooper, Ian & Kaplanis, Evi, 1994. "Home Bias in Equity Portfolios, Inflation Hedging, and International Capital Market Equilibrium," Review of Financial Studies, Society for Financial Studies, vol. 7(1), pages 45-60.
  26. Dow, James & Werlang, Sergio Ribeiro da Costa, 1992. "Uncertainty Aversion, Risk Aversion, and the Optimal Choice of Portfolio," Econometrica, Econometric Society, vol. 60(1), pages 197-204, January.
  27. Zoran Ivkovic & Scott Weisbenner, 2005. "Local Does as Local Is: Information Content of the Geography of Individual Investors' Common Stock Investments," Journal of Finance, American Finance Association, vol. 60(1), pages 267-306, 02.
  28. Epstein, Larry G. & Miao, Jianjun, 2003. "A two-person dynamic equilibrium under ambiguity," Journal of Economic Dynamics and Control, Elsevier, vol. 27(7), pages 1253-1288, May.
  29. H. Henry Cao & Tan Wang & Harold H. Zhang, 2005. "Model Uncertainty, Limited Market Participation, and Asset Prices," Review of Financial Studies, Society for Financial Studies, vol. 18(4), pages 1219-1251.
  30. Joshua D. Coval & Tobias J. Moskowitz, 1999. "Home Bias at Home: Local Equity Preference in Domestic Portfolios," Journal of Finance, American Finance Association, vol. 54(6), pages 2045-2073, December.
  31. Sergei Sarkissian, 2004. "The Overseas Listing Decision: New Evidence of Proximity Preference," Review of Financial Studies, Society for Financial Studies, vol. 17(3), pages 769-809.
  32. Myron S. Scholes, 2000. "Crisis and Risk Management," American Economic Review, American Economic Association, vol. 90(2), pages 17-21, May.
  33. Sujoy Mukerji & Peter Klibanoff, 2002. "A Smooth Model of Decision,Making Under Ambiguity," Economics Series Working Papers 113, University of Oxford, Department of Economics.
  34. Pascal J. Maenhout, 2004. "Robust Portfolio Rules and Asset Pricing," Review of Financial Studies, Society for Financial Studies, vol. 17(4), pages 951-983.
  35. Merton, Robert C., 1987. "A simple model of capital market equilibrium with incomplete information," Working papers 1869-87., Massachusetts Institute of Technology (MIT), Sloan School of Management.
  36. Victor DeMiguel & Lorenzo Garlappi & Raman Uppal, 2009. "Optimal Versus Naive Diversification: How Inefficient is the 1-N Portfolio Strategy?," Review of Financial Studies, Society for Financial Studies, vol. 22(5), pages 1915-1953, May.
  37. Gilboa, Itzhak & Schmeidler, David, 1989. "Maxmin expected utility with non-unique prior," Journal of Mathematical Economics, Elsevier, vol. 18(2), pages 141-153, April.
  38. Uppal, Raman & Wang, Tan, 2002. "Model Misspecification and Under-Diversification," CEPR Discussion Papers 3304, C.E.P.R. Discussion Papers.
  39. Meulbroek, Lisa, 2005. "Company Stock in Pension Plans: How Costly Is It?," Journal of Law and Economics, University of Chicago Press, vol. 48(2), pages 443-74, October.
  40. Stijn Van Nieuwerburgh & Laura Veldkamp, 2009. "Information Immobility and the Home Bias Puzzle," Journal of Finance, American Finance Association, vol. 64(3), pages 1187-1215, 06.
  41. Heath, Chip & Tversky, Amos, 1991. "Preference and Belief: Ambiguity and Competence in Choice under Uncertainty," Journal of Risk and Uncertainty, Springer, vol. 4(1), pages 5-28, January.
  42. Epstein, Larry G & Wang, Tan, 1994. "Intertemporal Asset Pricing Under Knightian Uncertainty," Econometrica, Econometric Society, vol. 62(2), pages 283-322, March.
  43. Campbell R. Harvey & Akhtar Siddique, 2000. "Conditional Skewness in Asset Pricing Tests," Journal of Finance, American Finance Association, vol. 55(3), pages 1263-1295, 06.
  44. Harry Markowitz, 1952. "Portfolio Selection," Journal of Finance, American Finance Association, vol. 7(1), pages 77-91, 03.
  45. Lei Feng & Mark S. Seasholes, 2004. "Correlated Trading and Location," Journal of Finance, American Finance Association, vol. 59(5), pages 2117-2144, October.
  46. Frost, Peter A. & Savarino, James E., 1986. "An Empirical Bayes Approach to Efficient Portfolio Selection," Journal of Financial and Quantitative Analysis, Cambridge University Press, vol. 21(03), pages 293-305, September.
  47. Easley, David & O'Hara, Maureen, 2010. "Liquidity and valuation in an uncertain world," Journal of Financial Economics, Elsevier, vol. 97(1), pages 1-11, July.
  48. Anderson, Evan W. & Ghysels, Eric & Juergens, Jennifer L., 2009. "The impact of risk and uncertainty on expected returns," Journal of Financial Economics, Elsevier, vol. 94(2), pages 233-263, November.
  49. Shefrin, Hersh & Statman, Meir, 2000. "Behavioral Portfolio Theory," Journal of Financial and Quantitative Analysis, Cambridge University Press, vol. 35(02), pages 127-151, June.
  50. Larry Epstein & Martin Schneider, 2002. "Learning Under Ambiguity," RCER Working Papers 497, University of Rochester - Center for Economic Research (RCER), revised Mar 2005.
  51. Nicholas Barberis & Ming Huang, 2007. "Stocks as Lotteries: The Implications of Probability Weighting for Security Prices," NBER Working Papers 12936, National Bureau of Economic Research, Inc.
  52. Louis K.C. Chan & Jason Karceski & Josef Lakonishok, 1999. "On Portfolio Optimization: Forecasting Covariances and Choosing the Risk Model," NBER Working Papers 7039, National Bureau of Economic Research, Inc.
  53. Jianjun Miao & Takashi Hayashi, 2010. "Intertemporal substitution and recursive smooth ambiguity preferences," Boston University - Department of Economics - Working Papers Series WP2010-030, Boston University - Department of Economics.
  54. Longin, Francois & Solnik, Bruno, 1995. "Is the correlation in international equity returns constant: 1960-1990?," Journal of International Money and Finance, Elsevier, vol. 14(1), pages 3-26, February.
  55. Brad M. Barber & Terrance Odean, 2000. "Trading Is Hazardous to Your Wealth: The Common Stock Investment Performance of Individual Investors," Journal of Finance, American Finance Association, vol. 55(2), pages 773-806, 04.
  56. Craig R. Fox & Amos Tversky, 1995. "Ambiguity Aversion and Comparative Ignorance," The Quarterly Journal of Economics, Oxford University Press, vol. 110(3), pages 585-603.
  57. Ser-Huang Poon, 2004. "Extreme Value Dependence in Financial Markets: Diagnostics, Models, and Financial Implications," Review of Financial Studies, Society for Financial Studies, vol. 17(2), pages 581-610.
  58. Shlomo Benartzi, 2001. "Excessive Extrapolation and the Allocation of 401(k) Accounts to Company Stock," Journal of Finance, American Finance Association, vol. 56(5), pages 1747-1764, October.
  59. Mark Grinblatt, 2001. "How Distance, Language, and Culture Influence Stockholdings and Trades," Journal of Finance, American Finance Association, vol. 56(3), pages 1053-1073, 06.
  60. Best, Michael J & Grauer, Robert R, 1991. "On the Sensitivity of Mean-Variance-Efficient Portfolios to Changes in Asset Means: Some Analytical and Computational Results," Review of Financial Studies, Society for Financial Studies, vol. 4(2), pages 315-42.
Full references (including those not matched with items on IDEAS)

This item is not listed on Wikipedia, on a reading list or among the top items on IDEAS.

When requesting a correction, please mention this item's handle: RePEc:cpr:ceprdp:7687. 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: ()

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 references are entirely missing, you can add them using this form.

If the full references list an item that is present in RePEc, but the system did not link 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 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.

This information is provided to you by IDEAS at the Research Division of the Federal Reserve Bank of St. Louis using RePEc data.