It is well documented that stock prices on ex-dividend days drop by less than the value of the dividend, on average. This has commonly been attributed to the effect of tax clienteles. We examine data from the Hong Kong stock market, where neither dividends nor capital gains are taxed. As in the U.S., the average stock price drop is less than the value of the dividend; specifically, the average dividend for the period 1980–1993 is HK 0.12 and the average price drop is HK 0.06. We are able to account for this both theoretically and empirically through market microstructure arguments.

Without the assumption of conditional homoskedasticity, a general asymptotic distribution theory for the two‐stage cross‐sectional regression method shows that the standard errors produced by the Fama–MacBeth procedure do not necessarily overstate the precision of the risk premium estimates. When factors are misspecified, estimators for risk premiums can be biased, and the t ‐value of a premium may converge to infinity in probability even when the true premium is zero. However, when a beta‐pricing model is misspecified, the t ‐values for firm characteristics generally converge to infinity in probability, which supports the use of firm characteristics in cross‐sectional regressions for detecting model misspecification.