Discrepancy in content experiment sessions

Question

I noticed a huge discrepancy in the count of sessions for one of our experiments in Google Analytics.

The API says 3,123 sessions for variation 0 and 3,039 for variation 1. GA API screenshot
At the same time the report in google.com/analytics reads 5,743 for variation 0 and 5,620 for variation 1. GA Web screenshot

The above data is:
- on the exact same dates
- with no filters
- with no segments
- on the same Google Analytics view id

Could you please help me figure this out?

Thanks, V.

Answer 1

The thing is that ga_sessions in query explorer (api) is not the same as experiment sessions in content experiments interface.

Read this for more information on experiment conversion rate and sessions calculation: https://support.google.com/analytics/answer/6112437#

Here is a quotation:

Conversion rate is calculated using the same methodology as Analytics: total converted visits divided by total visits (once a user becomes a part of an experiment). A user is considered part of an experiment once he or she has seen the experiment page. For example, if a user sees the experiment page, then comes back the next day, the second visit is counted, even if the user does not view the experiment page again.