Forum Moderators: DixonJones
referer info isn't completely reliable as it can be spoofed or often is not available.
What I have donw in the past is use a cookie or a session to store the original referer and then when the customer purchases, or executes whatever your conversion action is, then I would read that cookie/session info and add it to the purchase.
It's definitely true that the referrer field is suspect. Some kinds of (referring) web sites think it's a good idea to supply a fake identity but it depends on the market you're in. A far bigger problem is missing referrer information. (See elsewhere in WWW for "no referrer" discussions.) For example, in our experience, just about exactly 20% of all pay-per-click traffic from AdWords/Yahoo is missing the referrer and this percent has been rock-steady for 11 months now. (Your percentage will depend on your audience's mix of IE and other browsers.) Same problem for most banner traffic, at least for the publishers we work with. This means that when you have control over the entry page URL, as you do with Pay Per Click and banners, you should instead be putting markers in the URL to make sure the referrer is correctly credited in your stats.
[edited by: cgrantski at 9:03 am (utc) on July 10, 2006]