We subdivide trades on the London Stock Exchange according to their reaction times. We classify an aggressive order as 'fast' if it executes against a standing limit order that is less than 50 milliseconds old. We show that fast trades are associated with smaller execution costs than slow...

We study the relation between limit order flow, market order flow and returns. We develop a model where market-makers face inventory risk and adverse selection and show how prices depend on market and limit order flows. In the model, market-makers receive information through trade with customers...