GARCH-type models have been very successful in describing the volatility dynamics of financial return series for short periods of time. However, the time-varying behavior of investors, for example, may cause the structure of volatility to change and the assumption of stationarity is no longer...

This paper develops a tick time model for the quote setting dynamics on Nasdaq. The model decomposes quotes into an efficient price, asymmetric information and noise. Both the evolution of the efficient price and the information contents of quotes depend on quote durations. New measures for the...