Learning from prices: information aggregation and accumulation in an asset market
Tóm tắt
Can prices convey information about the fundamental value of an asset? This paper considers this problem in relation to the dynamic properties of the fundamental (whether it is constant or time-varying) and the structure of information available to agents. Risk-averse traders receive two potential signals each period: one exogenous and private and the other, prices, endogenous and public. Prices aggregate private information but include aggregate noise. Information can accumulate over time both through endogenous and exogenous signals. With a constant fundamental, the precision of both private and public cumulative information increases over time but agents put progressively more weight on the endogenous signals, asymptotically disregarding private ones. If the fundamental is time-varying, the use of past private signals complicates the role of prices as a source of information, since it introduces endogenous serial correlation in the price signal and cross-correlation between it and innovations in the fundamental. A modified version of the Kalman filter can still be used to extract information from prices and results show that the precision of the endogenous signals converges to a constant, with both private and public information used at all times.
Tài liệu tham khảo
Allen, F., Morris, S., Shin, H.S.: Beauty contests and iterated expectations in asset markets. Rev Financ Stud 19(3), 719–752 (2006)
Amador, M., Weill, P.-O.: Learning from private and public observations of others’ actions. J Econ Theory 147, 910–940 (2012)
Basak, S., Chabakauri, G.: Dynamic mean-variance asset allocation. Rev Financ Stud 23, 2970–3016 (2010)
Branch, W.A., Evans, G.W.: Learning about risk and return: a simple model of bubbles and crashes. Am Econ J: Macroecon 3, 159–191 (2011)
Diamond, D.W., Verrecchia, R.E.: Information aggregation in a noisy rational expectations economy. J Financ Econ 9, 221–235 (1981)
Elliott, R.J., Aggoun, L., Moore, J.B.: Hidden Markov Models: Estimation and Control. Springer-Verlag, New York (1995)
Grossman, S.: On the efficiency of competitive stock markets where traders have diverse information. J Financ 31, 573–585 (1976)
Grossman, S.: Further results on the informational efficiency of competitive stock markets. J Econ Theory 18, 81–101 (1978)
Grossman, S., Stiglitz, J.: On the impossibility of informationally efficient markets. Am Econ Rev 70, 393–408 (1980)
Hellwig, M.F.: On the aggregation of information in competitive markets. J Econ Theory 22, 477–498 (1980)
Jackson, M.: Equilibrium, price formation, and the value of private information. Rev Financ Stud 4, 1–16 (1991)
Kasa, K., Walker, T.B., Whiteman, C.H.: Heterogeneous beliefs and tests of present value models. Rev Econ Stud 81, 1137–1163 (2014)
Kyle, A.S.: Continuous auctions and insider trading. Econometrica 53, 1315–1335 (1985)
Kyle, A.S.: Informed speculation with imperfect competition. Rev Econ Stud 56, 317–356 (1989)
Li, X.R., Han, C., Wang, J.: Discrete-time linear filtering in arbitrary noise. In: Proceedings of the 39th IEEE Conference on Decision and Control 2, pp. 1212–1217 (2000)
Mele, A., Sangiorgi, F.: Uncertainty, information acquisition, and price swings in asset markets. Rev Econ Stud 82, 1533–1567 (2015)
Nimark, K.P.: Dynamic Higher Order Expectations. Working paper, mimeo (2017)
Sargent, T.J.: Equilibrium with signal extraction from endogenous variables. J Econ Dynam Control 15, 245–273 (1991)
Townsend, R.M.: Forecasting the forecasts of others. J Polit Econ 91, 546–588 (1983)
Vives, X.: How fast do rational agents learn? Rev Econ Stud 60, 329–347 (1993)
Vives, X.: Short-term investment and the information efficiency of the market. Rev Financ Stud 8, 125–160 (1995a)
Vives, X.: The speed of information revelation in a financial market mechanism. J Econ Theory 67, 178–204 (1995b)
Vives, X.: On the possibility of informationally efficient markets. J Eur Econ Assoc 12, 1200–1239 (2014)