Abstract
This article presents graphical techniques for visualizing concurrency in online auctions. These include rug plots, which allow for a compact view of many simultaneous auctions while preserving the structure of individual auctions. We also use box plots, moving statistics plots, and autocorrelation plots, supplemented by statistical tests. Together, these are used to study synchronous events and to surmise trends in the data, as well as to raise new research questions. We illustrate our methods on data from eBay.com. © 2006 American Statistical Association.