Omniture Site Catalyst: Props ,eVars and events

Omniture SiteCatalyst is one of the most advanced web analytics solutions available in the market today. SiteCatalyst's advanced reporting capabilities generate over 150,000 report combinations. Traffic reporting lets you analyze all aspects of visitor activity, such as traffic patterns, popular channels, referred technology and finding methods used .

 So How does SiteCatalyst collect data?

The SiteCatalyst data collection process is fairly basic. After proper development time, the SiteCatalyst code (or Code to Paste) is placed in the HTML source code on the desired pages of their production web site(s).

When a visitor enters your web site, your landing page loads in their browser window. As the page loads, the SiteCatalyst Code to Paste sets certain variables, for example, the pageName variable, and the SiteCatalyst JavaScript Include file. The variables (and other identifiers) are used to facilitate the data collection process, and can be dynamically populated with server or application variables.

The JavaScript Include file builds an image request, or web beacon. The image request uses a transparent 1x1 pixel image to pass data from the web page to the Omniture data center. No personal data about the visitors is ever passed to Omniture. The process is repeated every time the visitor accesses a page that contains SiteCatalyst code.

The image request contains a query string that passes the data variables that are collected on the page. Some of these variables are set specifically in the Code to Paste, and some variables are set automatically within the JavaScript file. Additionally, the image request contains a number of variables in the HTTP header. All of these variables constitute the sum of the data collection elements.



Props, eVars and events :

At the heart of SiteCatalyst's data collection methodology are Props, eVars and events. Props and eVars are variables that store data and pass them on to the data collection server, whereas events help in triggering data collection by these variables. Let's look into the variables in a little more detail:

Props and eVars:

Custom Insight Variables, also called props or property variables, are counters that count the number of times each value is sent into SiteCatalyst. They also enable you to correlate custom data with specific traffic-related events. s.prop variables are embedded in the SiteCatalyst code on each page of your website. Through s.prop variables, SiteCatalyst allows you to create custom reports, unique to your organization, industry, and business objectives. For example, if you are an automobile manufacturer you may be interested in seeing "Most Popular Car Model" to complement your "Most Popular Pages" report. You can accomplish this by allocating one of your traffic properties to represent car model and then implement your code to pass in car model on the appropriate pages.

There are endless business questions that can be answered through the Custom Insight Variables, depending on what you are capturing from your website. The following list contains a few common goals and objectives.

§ Understanding user navigation through the web site

§ Understanding internal user search behavior

§ Segmenting traffic by navigation or category

§ Segmenting visitor behavior by demographics

An important thing to note is that Props are non persistent variables. The values that are populated in these variables last only within the context of the particular page.


eVars (or Custom Conversion Insight Variables) are used to identify how well specific attributes or actions contribute to success events on your site. For example, for a media site, eVars may be used to identify how well internal promotions bring visitors to register. When a visitor clicks on the internal promotion, an eVar can be used to store a unique identifier for that promotion. When the same visitor completes registration and a custom success event is fired, the original unique identifier will receive credit for the registration event.

eVars are persistent variables and can be used to store a particular value throughout a session unless over written. They can be used to tie success events to custom variable.


Events are triggers that help in collection of data. For example in case you want to check how many time a certain product has been viewed, you can use an event that is fired each time that product page is viewed. Omniture offers predefined and Custom events which will discussed a later post.