We explore the time series properties of overnight and daytime returns on the London Stock Exchange's primary stock market index, the FTSE-100 on the over the 1984-1991 period. We use a modified GARCH model to specify daytime and overnight return dynamics where (a) intra-day returns can have different impacts and persistence on stock return volatility, (b) return effects on volatility can be asymmetric and (c) intra-day returns can follow conditional distributions with different fourth moments. We uncover important changes in return dynamics and conditional fourth moments following the stock exchange's major restructuring called quot;Big Bangquot;, which merged broker and dealer functions and after the1987 stock market crash.

I examine intraday stock returns in the Istanbul Stock Exchange (ISE) around non-trading periods - weekends and holidays - by utilizing the exchange's structure of two trading sessions. I find that returns are generally more positive in the last session on Fridays and more negative in the first session on Mondays. The results also indicate that the weekend effect has disappeared in the ISE in recent years. I further find some evidence that there is a relationship between the length of a holiday non-trading period and returns around it. The longer a non-trading period is, the more positive the returns are in the morning session before the holiday and the less positive the returns are in the morning session after the holiday. My findings indicate the importance of the uncertainty imposed on stock returns by the length of a non-trading period.

This paper uses transactions data from the London Stock Exchange to characterize the intraday pattern of security prices and trading volume for securities trading on SEAQ. It focuses in more detail on a sample of U.K. firms that are cross-listed on the NYSE. Using additional data from the NYSE-AMEX (I5SM), we compare volatility, volume, and quotes as trading starts in London and then continues in New York. These firms have substantially longer trading hours than most singly-listed stocks, and are also traded in two markets with very different institutional setups. This is shown to have several important implications for theories on intraday behavior of prices, the organization of exchanges, and the general consequences of round-the-clock trading.

This paper compares the intra-day patterns on the NYSE and AMEX of volatility, trading volume and bid-ask spreads for European dually- listed stocks, Japanese dually-listed stocks also listed in London, and Japanese dually-listed stocks not listed in London with American stocks of comparable average trading volume and volatility. It is shown that the intra-day patterns for these stocks are remarkably similar even though the public information flows differ markedly across these stocks during the trading day. In the morning, Japanese stocks have the greatest volatility and volume, followed by European stocks and American stocks. These rankings are reversed in the afternoon. We argue that these patterns are consistent with markets reacting to the overnight accumulation of public information which is greatest for Japanese stock and smallest for American stocks and inconsistent with the view that early morning volatility can be attributed to monopolistic specialist behavior.