Stock Market Prices Do Not Follow Random Walks: Evidence from a Simple Specification Test
- 1 January 1988
- journal article
- research article
- Published by Oxford University Press (OUP) in The Review of Financial Studies
- Vol. 1 (1), 41-66
- https://doi.org/10.1093/rfs/1.1.41
Abstract
In this article we test the random walk hypothesis for weekly stock market returns by comparing variance estimators derived from data sampled at different frequencies. The random walk model is strongly rejected for the entire sample period (1962–1985) and for all subperiods for a variety of aggregate returns indexes and size-sorted portfolios. Although the rejections are due largely to the behavior of small stocks, they cannot be attributed completely to the effects of infrequent trading or time-varying volatilities. Moreover, the rejection of the random walk for weekly returns does not support a mean-reverting model of asset prices.Keywords
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This publication has 28 references indexed in Scilit:
- Are Output Fluctuations Transitory?The Quarterly Journal of Economics, 1987
- Expected stock returns and volatilityJournal of Financial Economics, 1987
- Stock return variancesJournal of Financial Economics, 1986
- Some robust exact results on sample autocorrelations and tests of randomnessJournal of Econometrics, 1985
- Friction in the trading process and the estimation of systematic riskJournal of Financial Economics, 1983
- Autoregressive Conditional Heteroscedasticity with Estimates of the Variance of United Kingdom InflationEconometrica, 1982
- RANK TESTS FOR SERIAL DEPENDENCEJournal of Time Series Analysis, 1981
- Specification Tests in EconometricsEconometrica, 1978
- Efficient Capital Markets: A Review of Theory and Empirical WorkThe Journal of Finance, 1970
- The Behavior of Stock-Market PricesThe Journal of Business, 1965