Hostname: page-component-cd9895bd7-p9bg8 Total loading time: 0 Render date: 2024-12-25T07:26:14.945Z Has data issue: false hasContentIssue false

Portfolio Selection with an Imperfectly Competitive Asset Market

Published online by Cambridge University Press:  19 October 2009

Extract

Traditional models of portfolio selection assume that all assets are traded in competitive markets, so that rates of return to any individual investor are fixed. This paper represents an extension of portfolio theory to the case in which asset markets are not perfectly competitive and rates of return cannot be taken as given. Klein [10] has noted that, when asset markets are imperfect, the separation theorem no longer holds but does not solve explicitly for the relationship between risk and return. Here for simplicity we shall consider the case of the investor who has a monopoly in an asset he creates, so that its risk and return characteristics are determined by the decisions of the portfolio selector and hence are endogenous. It will be shown that even if the market for an asset in the portfolio is imperfectly competitive, as long as the demand curve for the asset is well behaved, the locus of efficient portfolios facing the investor, which is composed of combinations of the riskless asset and the optimal combination of risky assets, will be a concave function, as opposed to a linear function in the competitive case. In other words, the introduction of capital market imperfections does not affect the positive slope of the efficient set of portfolios. Moreover, the expected return on the imperfectly competitive asset will be shown to be easily decomposable into the standard risk premium and a monopoly premium.

Type
Research Article
Copyright
Copyright © School of Business Administration, University of Washington 1976

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

[1]Alhadeff, D.Monopoly and Competition in Banking. Berkeley: University of California Press, 1954.CrossRefGoogle Scholar
[2]Cohn, R., and Pringle, J.. “Steps toward an Integration of Corporate Financial Theory.” In Management of Working Capital, edited by Smith, K. V.. St. Paul, Minn.: West Publishing Co., 1975.Google Scholar
[3]Daly, G.Financial Intermediation and the Theory of the Firm.” Southern Economic Journal, Vol. 37, No. 3 (January 1971), pp. 283295.CrossRefGoogle Scholar
[4]Emery, J.;Risk, Return, and the Morphology of Commercial Banking.” Journal of Financial and Quantitative Analysis, Vol. 6, No. 2 (March 1971), pp. 763781.CrossRefGoogle Scholar
[5]Fried, J.Bank Portfolio Selection.” Journal of Financial and Quantitative Analysis, Vol. 5, No. 2 (June 1970), pp. 203227.CrossRefGoogle Scholar
[6]Hart, O. D., and Jaffee, D. M.. “On the Application of Portfolio Theory to Depository Financial Intermediaries.” Review of Economic Studies, Vol. 21, No. 125 (January 1974), pp. 129147.CrossRefGoogle Scholar
[7]James, J. “The Evolution of the National Money Market, 1888–1911.” Unpublished Ph.D. dissertation, MIT, 1974.Google Scholar
[8]Kane, E., and Malkiel, B.. “Bank Portfolio Allocation, Deposit Variability, and the Availability Doctrine.” Quarterly Journal of Economics, Vol. 79, No. 1 (February 1965), pp. 113134.CrossRefGoogle Scholar
[9]Klein, M.The Economics of Security Divisibility and Financial Intermediation.” Journal of Finance, Vol. 28, No. 4 (September 1973), pp. 923932.CrossRefGoogle Scholar
[10]Klein, M.Imperfect Asset Elasticity and Portfolio Theory.” American Economic Review, Vol. 60, No. 3 (June 1970), pp. 491494.Google Scholar
[11]Klein, M.A Theory of the Banking Firm.” Journal of Money, Credit, and Banking, Vol. 3, No. 2 (May 1971), pp. 205218.CrossRefGoogle Scholar
[12]Michaelsen, J., and Goshay, R.. “Portfolio Selection in Financial Intermediaries: A New Approach.” Journal of Financial and Quantitative Analysis, Vol. 2, No. 2 (June 1967), pp. 166199.CrossRefGoogle Scholar
[13]Milne, F.Corporate Investment and Finance Theory in Competitive Equilibrium.” Economic Record, Vol. 50, No. 132 (December 1974), pp. 511533.CrossRefGoogle Scholar
[14]Pringle, J.The Capital Decision in Commercial Banks.” Journal of Finance, Vol. 29, No. 3 (June 1974), pp. 779795.CrossRefGoogle Scholar
[15]Pringle, J.The Imperfect-Markets Model of Commercial Bank Financial Management.” Journal of Financial and Quantitative Analysis, Vol. 9, No. 1 (January 1974), pp. 6987.CrossRefGoogle Scholar
[16]Pyle, D.Descriptive Theories of Financial Institutions under Uncertainty. Journal of Financial and Quantitative Analysis, Vol. 7, No. 5 (December 1972), pp. 20092029.CrossRefGoogle Scholar
[17]Pyle, D.On the Theory of Financial Intermediation.” Journal of Finance, Vol. 26, No. 3 (June 1971), pp. 737748.CrossRefGoogle Scholar
[18]Russell, W.Commercial Bank Portfolio Adjustments.” American Economic Review, Vol. 54, No. 3 (May 1964), pp. 544553.Google Scholar
[19]Samuelson, P.Foundations of Economic Analysis. Cambridge, Mass.: Harvard University Press, 1947.Google Scholar
[20]Sharpe, W.Capital Asset Prices: A Theory of Market Equilibrium under Conditions of Risk.” Journal of Finance, Vol. 19, No. 3 (September 1964), pp. 425442.Google Scholar
[21]Sharpe, W.Portfolio Theory and Capital Markets. New York: McGraw-Hill, 1970.Google Scholar
[22]Tobin, J.Liquidity Preference as Behavior towards Risk.” Review of Economic Studies, Vol. 25, No. 2 (February 1958), pp. 6586.CrossRefGoogle Scholar