Context: We are investigating a data discrepancy between number of clicks in Google Ads and sessions in Google analytics (3000 clicks but only 500 sessions). We are using the standard Google Analytics "Global Site Tag (gtag.js)" snippet on the landing pages. There are additional trackers being used as well (facebook, twitter, etc.)
Test performed: Tester clicks on Google Ad in Google search results and performs a conversion action (signup). We look at a segment which shows this particular action (filter on country / city)
We observe different (source / medium) attributions, depending on which report we look at.
- In "Behavior > Events > Top Events" we see source / medium as (l.facebook.com / referral) which I think is incorrect, since tester was coming from the Google search results page, not from facebook
- In "Acquisition > Campaigns > All Campaigns" we see source / medium as (google / cpc), which I would consider to be more correct since the tester clicked on the advertisement on the Google search results page.
It appears that one session could have multiple (source / medium) attributions, is that correct, and could someone explain how this works? Are there different (source / medium) attributions depending on the filter?