Data Characteristics

Before presenting the analysis, we briefly describe the different ways in which the web site is accessed, the characteristics of the data logs, and the types of analyses we carried out. For the web server we used in this study, a single browse request results in exactly one HTTP request to the server. There are no images or other types of content embedded in the page that is transmitted to the client as a result of this request. In the rest of the paper, we use the term notification document to refer to a unique document that may be sent to multiple users; we refer to each such transmission as a notification message, which includes duplicates.