We examine empirically the role of high-frequency traders (HFTs) in price discovery and price efficiency. Based on our methodology, we find overall that HFTs facilitate price efficiency by trading in the direction of permanent price changes and in the opposite direction of transitory pricing...

This paper studies whether high-frequency trading (HFT) increases the execution costs of institutional investors. We use technology upgrades that lower the latency of the London Stock Exchange to obtain variation in the level of HFT over time. Following upgrades, the level of HFT increases....

We analyze trading dynamics as successive high-frequency trading (HFT) firms begin to trade stocks in an equity market. Entrants compete with incumbents for volume, and there is crowding out. Earlier entry is associated with larger effects. After Passive HFT entry, incumbent spreads tighten....

Using detailed publication and citation data for over 50,000 articles from 30 major economics and finance journals, we investigate whether network proximity to an editor influences research productivity. During an editor's tenure, his current university colleagues publish about 100% more papers...

The speed of trading is an important factor in modern security markets. We still know relatively little about the e ffect of speed on liquidity and price discovery, two important aspects of market quality. On April 23rd, 2007, Deutsche Boerse made the most important upgrade to their trading...

Using a unique data set with 18.1 million transactions in bank-issued warrants from the European Warrant Exchange, we compute a retail investor sentiment index. We show that retail investors are contrarian, that retail investor sentiment is an important part of the equity pricing process and...