admob impressions vs analytics screenviews

Question

Android

Good afternoon. The question is why the number of screen views according to google analytics does not match the number of ad impressions in admob.
Approximate statistics for the same period looks like this:
admob:
Requests: 1000
Impressions: 1000
Fill rate: 100%
analytics:
Screen views: 1300
Where does the third go?

Answer 1

Well, at least not all countries have ads
, and probably due to some restrictions, ads are not shown to users

Answer 2

I may be wrong, but Screenviews != Impressions in admob mk
1. Watching 1 screen for a long time may show a few ads (frequency is adjustable in admob)
2. If you request ads from admob several times in a short period (more often than the parameter from n1), then the same ad will appear and most likely admob will count for 1 impression.
PS I'm not a specialist in admob and analytics, but there is a small application in which all this is used