Using electronic order flow data for a sample of NYSE-listed stocks, we examine the relative importance of program traders, institutional traders, retail traders, and exchange members in driving commonality in order flow, returns, and liquidity. Using principal components analysis, we find that...

Though trading halts are a common feature in securities markets, the issues associated with the coordination of these halts across markets are not well understood. In fact, regulations often allow traders to circumvent trading halts through the use of alternative venues. Using a sample of order...