Google Analytics vs. Ad Server Reporting
I know this is somewhat of an old subject and there are numerous blog posts and basic info available out there, but I am interested in getting some feedback from the field.
Google Analytics vs. Ad Servers
Over the past year and a half, we have experienced a noticeable increase in advertisers that are using Google Analytics to verify/validate our publisher side ad server metrics, particularly click-thrus. We have seen GA report as little as 1/3rd of clicks as visits. I have done a lot of research on why this may be, including the different counting methodologies (clicks vs. visits) and tracking mechanisms (cookies vs. IP and user agent)but it still seems almost impossible to me that there would be such a difference in the reporting.
For instance, if a campaign reports having 100 clicks in our ad server, but GA reports only 25 visits, that would indicate that each user clicked on an ad 4 times within a 30 minute time frame. That seems unlikely, and I can't imagine that the other issues that have been uncovered would result in such differences.
We have had some advertisers state that they are not seeing as large a discrepancy with other Publishers. So, I am working to discover if there are any patterns based on ad server, ad placement, rich media, etc. that could help uncover a source(s)of the problem and at least narrow the gap.
If any of you have experienced the same issue, I would appreciate any info you may have, along with what publisher you work with and what ad server you use. We use RealMedia 24/7's OpenAdStream Central as our ad server, and I know that a few other publishers that use OAS have experienced this issue.
Thanks in advance,
Manager, Ad Ops and Analytics
The Seattle Times.