Using unique transactions data for individual high-frequency trading (HFT) firms in the UK equity market, we examine if the trading activity of individual HFT firms is contemporaneously and dynamically correlated with each other, and what impact this has on price efficiency. We find that HFT...

We study the evolution of the price discovery process in the euro-dollar and dollar-yen currency pairs over a ten-year period on the EBS platform, a global trading venue used by both manual and automated traders. We find that the importance of market orders decreases sharply over that period,...