Last fall Google announced the release of the much anticipated Custom Variables in Google Analytics. Previously the only out of the box way to segment visitors on your site using custom metrics was to use the User Defined variable. While the User Defined method was useful for segmenting traffic into members vs non members, and for things like Michael’s Exact Keyword Tracking script, Analytics users requested more options, customizations, and more control. Well, Google listened.
Unlike the User Defined variable, the Custom Variables allow you to determine the scope of the visitor engagement. Basically that means in addition to setting just a visitor level segment, you can also set session level segments, which will persist while the visitor is active on the site, and page level segments, which correspond to pageviews and events on the site. This allows you to get much more detailed with the information you’re gathering and storing in the custom variable. For example, you could separate different sections of the site by using the page level scope, or you could track if a visitor has completed a particular action during their session with the session level scope.
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