Why do Google Analytics and the statistics panel disagree?

Google Analytics and the Statistics panel collect data in different ways, and give different results.

How Google Analytics collects data

Google Analytics tracks visitors using a small JavaScript file that a visitor’ browser requests each time they view a page. If the visitor’s browser does not request the JavaScript file, they are not tracked by Google Analytics. Reasons for not requesting the JavaScript file include:

In order to determine the number of distinct visits, Google Analytics uses a cookie — a small text file stored by the visitor’s browser, which is sent to the site with every request. If the visitor’s browser blocks the cookie, their visits cannot be tracked. Reasons for blocking the cookie include:

How the editing system collects data

The editing system counts all page views. It can determine these with complete accuracy as it is responsible for generating the pages being viewed.

From the page views it determines the number of distinct visits using the referrer header — a piece of information sent by a browser when it requests a page. If the visitor followed a link, the referrer header contains the address of the page containing the link. In other situations (for example, if the visitor has clicked on one of their bookmarks) the referrer header is blank.

If the referrer header is blank or contains the address of a page on another site, the editing system counts the page view as the start of a new visit. If the referrer header contains the address of a page on your site, the editing system counts the page view as the continuation of an existing visit.