For some traits, I'm seeing that the unique visitor volume in Audience Manager is as low as 50% of the volume that we're seeing in Adobe Analytics. Is that normal or does that seem to low? I know that AAM doesn't accept visitors with 3rd party cookies, so I'm sure the discrepancy varies by industry.
Are there any other reasons besides tagging mistakes and 3rd party cookies as to why there would be a discrepancy?
If we have set up server-side forwarding, and if I can see an event (e.g. prodview) has been tracked in Adobe Analytics but after I created a trait using that event, it has been returning 0 in AAM. What could be the reason of that?
I used c_events that contains "prodview", cart addition and purchase events all work fine.
Also, is "d_rs" the one to use when I want to include data from only one specific reporting suite. It is in the unused signal report and the "unique" look fine after i used it to create traits and segments in AAM. Are there any limitations when using it with others such as c_evar, c_prop, c_events, etc?
There could be a number reasons. I'll list a few below:
AAM only counts visitors that use browsers that accept 3rd party cookies (Safari does not so if your site has a large mobile presence, that could be a big one)
Analytics might have duplicate visitors for one user. If the visitor visits multiple sites that report to the same report suite and they didn't have cross domain tracking setup properly it could inflate Analytics numbers. Also, there are certain scenarios where even if they did have the cross-domain setup properly it may not have worked because of the path the visitor choose to take.
Analytics might be deployed on more web properties than AAM
The Marketing Cloud ID service (likely to be changed to the Experience Cloud ID service) is helping to combat some of these difference. Before we had MCID, each solution identified a visitor or user in a different way. It's best not to compare these numbers to each other. If you want a better representation, try looking at numbers after you've deployed MCID.
I'll copy our AAM and Analytics community managers here in case they have anything to add. Gaurang Mathur & Gigazelle