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Web Analytics Association
Web Analytics Definitions – Version 4.0
Authors: Jason Burby, Angie Brown & WAA Standards Committee
Page 18
TERM: Referrer
Type: Dimension
Universe: Aggregate, Segmented, Individual
Definition/Calculation:
The referrer is the page URL that originally generated the request for the current
page view or object.
Comments:
The referrer is a field in the request header from a client. Most of the time the
referrer is the value of this field. If the link is contained within a frame, most analytic
tools will navigate through the frames to collect the referrer of the top-most page
containing the frame. Also the original link may be redirected to another URL one or
more times. Typically the redirecting server will maintain the original referrer so that
rendered page will have the referrer URL of the page that started the sequence of
requests. For log-based analytic tools, the referrer is the referrer value in the request
header.
Each hit to a website has a referrer. However there are several situations where the
referrer value is empty or null. Some user agents such as email clients or news
readers may not set the referrer value in the request header. For browser user-
agents, an empty referral string usually indicates that the user either directly
entered the URL or selected from a list of bookmarks. These are often reported as
"No Referrer" or "Direct Navigation".
In the case when the visitor is coming from outside the website, the referrer value is
the only way of determining where the visitor came from or who referred the visitor
to the website. Furthermore the referrer URL may be accompanied by parameters
that convey additional important information. For example, the content that was
viewed or the keyword that was searched in the case of search portals may be
passed through parameters.
Specific Referrer Types:
Internal Referrer, External Referrer, Search Referrer, Visit Referrer, Original Referrer