Price clustering in E‐mini and floor‐traded index futures

This article sets out to investigate price clustering in both the open‐outcry (floor‐traded) and electronically traded (E‐mini) index futures markets of the DJIA, S&P 500, and NASDAQ‐100 indices. The results show that although price clustering is ubiquitous in both the floor‐traded and E‐mini index futures markets, it nevertheless tends to be higher for open‐outcry index futures, with the clustering in floor‐traded NASDAQ‐100 index futures demonstrating the highest level (97%) at zero digits. A significant increase was also found in price clustering in floor‐traded index futures after the introduction of E‐mini futures trading. The results tend to suggest that those trading mechanisms that involve higher levels of human participation, such as the open‐outcry markets, may well lead to increased incidences of price clustering. © 2006 Wiley Periodicals, Inc. Jrl Fut Mark 26: 269–295, 2006