Tj. George et Cy. Hwang, TRANSITORY PRICE CHANGES AND PRICE-LIMIT RULES - EVIDENCE FROM THE TOKYO STOCK-EXCHANGE, Journal of financial and quantitative analysis, 30(2), 1995, pp. 313-327
We compare the volatility of 24-hour returns computed from the opening
and closing prices of a diverse sample of Tokyo Stock Exchange (TSE)
stocks. We find that volatility at the open is greater than volatility
at the close only for the most actively traded TSE stocks. Daytime an
d overnight return covariances suggest that the volatility patterns ar
e explained by the effect of implicit bid-ask spreads at the open and
partial price adjustment at the close, both of which are related to th
e intensity of trading. Our results challenge the view that open-to-op
en returns are more volatile than close-to-close returns for stocks, i
n general, and are consistent with the hypothesis that TSE price limit
rules have a significant impact on the dynamics of security prices.