Adobe "All Visits" Segment Data Discrepancy

[tkirwin]

Why would the Adobe Default "All Visits" segment result in a different count of "Unique Visitors" and "Visits" vs using "Page Dimension" and "Unique Visitors" and "Visits"? 

[samk10]

The aggregate will only be accurate when you look at Unique visitors and visits at a page level. This is because in a single visit, someone can view multiple pages, and that's what you get for each page (count of visits). So, for example, in one visit, if I view Page 1 and Page 2, both the pages will have one visit each, and the total will be 2 (that's what you see in your top image).

Whereas when you look at the segment, the data is deduplicated, which means, in the above example, it still counts the total visit as 1.

Hope this helps you understand the difference.

[tkirwin]

I was always told that the top line aggregate number was deduped for visitors. If I sum all rows for Visitor count it would be higher than the top line sum as a visitor can view more than one page in a session. In fact, a test with my visitor id verifies that this is indeed deduped. The All Visits visitors and Page visitors are deduped thus the numbers should be equal. The visit number could be "squishy" depending on when the session of a user started and ended on any given set of pages. You can see that the aggregate delta or difference is not as exasperated between Page Visits and All Visits.

When using the month I get the same result as all visits which is as expected - I believe it all depends on the dimension being used.

[Jennifer_Dungan · Accepted solution]

You are correct about the column totals de-duplicating UVs and Vs... if that wasn't the case, the value of those columns would be higher, not lower.

But the key is looking at the "grand total" in your screenshot for table 1.

154,973 out of 155,223
and
185,648 out of 186,861

Your breakdown is by your "Page" dimension, this would mean that you have actions that are being tracked where those users aren't actually hitting pages. Do you maybe have embedded tracking on a Newsletter that is triggering as an "action" but not a "page view". Or maybe there are scenarios in your site where an action is triggered before the page view - and users trigger that, then bounce before the actual page view has occurred.

UVs and Vs will count against any hit, not just pages.... but when you are looking at Page data, the non-page data won't be included in the total; hence why the values are smaller than the Month or "All Visits" data.