We study the impact on market liquidity of the introduction of a penalty for high order-to-trade ratios (OTRs), implemented by the Italian stock exchange to curtail high-frequency quote submission. We find that the fee is associated with a collapse in the quoted depth of the stocks that make up...

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...

Does it matter to market quality if broker identities are revealed after a trade and only to the two traders involved? We find that implementing full anonymity dramatically improves liquidity and reduces trader execution costs. To explain this, we compare theories based on asymmetric information...