In the world of Digital Campaigns whenever creative is being served through Ad Tags it means the ad delivery is being tracked using two sets of numbers: The Publisher's numbers (as reported by their Ad Server) and the Third Party Vendor's numbers (as reported thru the Ad Server of the Vendor used to traffic the ads). The difference between these two sets of numbers is referred to as a Discrepancy.
What causes discrepancies?
Discrepancies are a by-product of counting methodology. In other words it's the difference between when a Publisher considers an Impression "counted" and when the Third Party considers the same impression "counted". Additionally, different vendors may count their impressions at different times in the ad delivery process so discrepancies can vary by vendor. Here's another way of looking at this:
What causes discrepancies?
Discrepancies are a by-product of counting methodology. In other words it's the difference between when a Publisher considers an Impression "counted" and when the Third Party considers the same impression "counted". Additionally, different vendors may count their impressions at different times in the ad delivery process so discrepancies can vary by vendor. Here's another way of looking at this:
If either ad response fails prior to the 3rd Party’s count (Vendor X does not respond with content, Vendor Y’s content does not load), then the impression is not captured on the vendor's end. The result is a discrepancy between the Publisher and Third Party impression counts.
What is considered a normal discrepancy?
Agencies and Publishers typically consider a discrepancy of up to 10% normal, and most vendors will not troubleshoot anything less than this amount. My experience has been that most discrepancies range 2% - 5% depending on the vendor.
How do Publishers compensate for discrepancies?
When trafficking a campaign that is billed using 3rd Party numbers, a Publisher will "overbook" the goals on the campaign by a default or anticipated discrepancy percentage to ensure that the Advertiser's contracted goal is met.
For more on discrepancies you can read about the Impression Exchange Solution: An industry-wide standard mechanism designed to create immediate awareness and transparency around discrepancies.
What is considered a normal discrepancy?
Agencies and Publishers typically consider a discrepancy of up to 10% normal, and most vendors will not troubleshoot anything less than this amount. My experience has been that most discrepancies range 2% - 5% depending on the vendor.
How do Publishers compensate for discrepancies?
When trafficking a campaign that is billed using 3rd Party numbers, a Publisher will "overbook" the goals on the campaign by a default or anticipated discrepancy percentage to ensure that the Advertiser's contracted goal is met.
For more on discrepancies you can read about the Impression Exchange Solution: An industry-wide standard mechanism designed to create immediate awareness and transparency around discrepancies.