The role of time in price discovery

Abstract

In this paper we investigate the price effects of trading intensity. Extending on the Madhavan et al. (1997) model, we split the intensity effect into liquidity and information effects. We provide a measure of market quality that is the ratio of the covariance bias to the variance bias. Analyzing about 6 years of tick by tick data, we find that the bid-ask spread in a pure limit order book market contains a risk component associated with managing the time to trade, and this component accounts for roughly 19.6% of the implied bid-ask spread. Extending our model to investigate intraday patterns, we find that the adverse selection cost exhibits a U-shaped pattern reflecting uncertainty at market openings in the Helsinki Stock Exchange (HEX) and in the New York Stock Exchange (NYSE). The results emphasize the importance of managing time in limit order book markets.