Webtrends Analytics 9 Adminstration Guide, November 2012
URL Parameter Analysis helps you understand requests for dynamic site content by allowing you to specify the query parameters of interest for each Basic Analysis profile. In order to maintain the performance of Basic Analysis profiles, you are limited to four Parameter Analysis reports for each profile.
If you have a programming resource for creating Webtrends plug-ins, you can report on additional web traffic data using URL Parameter Analysis. Programmers can create Webtrends plug-ins that retrieve log file data such as referrers (or any other supported field) and append the data to the query string for Webtrends to use in analysis. Because Webtrends can report on any parameter in the query string, you can use the URL Parameter Analysis feature to report on the data your plug-in appends to the query string. For example, if your plug-in appends referrer data to the query string using a parameter named ref, you specify the ref parameter in your profile, and Webtrends analyzes it and shows the traffic in your Parameter Analysis report. For more information about creating Webtrends plug-ins, see the Webtrends Programmer's Reference on the Webtrends Documentation page.