How can two ad blocks that are on the same page yield a different number of page impressions? Do some of them not load sometimes?
If there are not enough ads in the inventory for your keywords, it might load just one block, and the other would be a PSA(not counted in stats) or your alternate ad which is also not considered in stats
It happens to me too! Maybe is what you said, sometimes one doesn't have "time to load", the visitors leave your site before all open, i don't know...:/
I am almost positive it is, for tracking stats I have created channels for both of the ads on one of my pages and one has shown 8,587 times today and the other 8,142. I also have a replacement ad set up for that parciular ad block, which has been views 440 times today, I think it might be a little more than coincidense. "time to load" could also be a factor, but usually, once the initial connection to the server is made all ads load very quick. So it would be more than likely that either both would not load at all or both load just fine
hehe, I am not sure about the answer to this question that has been bothering adsense publishers for ages
my channels usually show the same number of impressions, with maybe 2 or 3 impressions discrepancies.