The Existence of Informationally Efficient Markets When Individuals Are Rational
A rational-expectations equilibrium with positive demand for financial information does exist under fully revealing asset price-contrary to a wide-held conjecture. Generalizing the common additive signal-return model with CARA utility to the family of distributions with moment generating functions, this paper shows that individual investors en- dowed with an average portfolio demand information in equilibrium if they can adjust portfolio size. More information diminishes the ex- pected excess return of a risky asset so that investors who only have a choice of portfolio composition or whose asset endowments strongly differ from the average portfolio are worse off. Under fully revealing price, information market equilibria both with and without informa- tion acquisition are Pareto efficient.
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- Routledge, Bryan R, 1999. "Adaptive Learning in Financial Markets," Review of Financial Studies, Society for Financial Studies, vol. 12(5), pages 1165-1202.
- Morris, Stephen & Shin, Hyun Song, 1998.
"Unique Equilibrium in a Model of Self-Fulfilling Currency Attacks,"
American Economic Review,
American Economic Association, vol. 88(3), pages 587-97, June.
- Morris, S & Song Shin, H, 1996. "Unique Equilibrium in a Model of Self-Fulfilling Currency Attacks," Economics Papers 126, Economics Group, Nuffield College, University of Oxford.
- Morris, Stephen & Shin, Hyun Song, 1997. "Unique Equilibrium in a Model of Self-fulfilling Currency Attacks," CEPR Discussion Papers 1687, C.E.P.R. Discussion Papers.
- Jordan, J S, 1983. "On the Efficient Markets Hypothesis," Econometrica, Econometric Society, vol. 51(5), pages 1325-43, September.
- Admati, Anat R., 1991. "The informational role of prices : A review essay," Journal of Monetary Economics, Elsevier, vol. 28(2), pages 347-361, October.
- Gadi Barlevy & Pietro Veronesi, .
"Information Acquisition in Financial Markets,"
CRSP working papers
360, Center for Research in Security Prices, Graduate School of Business, University of Chicago.
- repec:hal:journl:hal-00463207 is not listed on IDEAS
- Romer, David, 1993.
"Rational Asset-Price Movements without News,"
American Economic Review,
American Economic Association, vol. 83(5), pages 1112-30, December.
- Grossman, Sanford J & Stiglitz, Joseph E, 1976. "Information and Competitive Price Systems," American Economic Review, American Economic Association, vol. 66(2), pages 246-53, May.
- Bhattacharya, Sudipto & Pfleiderer, Paul, 1985. "Delegated portfolio management," Journal of Economic Theory, Elsevier, vol. 36(1), pages 1-25, June.
- Radner, Roy, 1979. "Rational Expectations Equilibrium: Generic Existence and the Information Revealed by Prices," Econometrica, Econometric Society, vol. 47(3), pages 655-78, May.
- Jackson, Matthew O, 1991. "Equilibrium, Price Formation, and the Value of Private Information," Review of Financial Studies, Society for Financial Studies, vol. 4(1), pages 1-16.
- Citanna, Alessandro & Villanacci, Antonio, 2000. "Existence and regularity of partially revealing rational expectations equilibrium in finite economies," Journal of Mathematical Economics, Elsevier, vol. 34(1), pages 1-26, August.
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