walkman - 5:08 pm on Oct 16, 2011 (gmt 0)
I've been noticing those "deep clicks" for several years and they really puzzle me. It doesn't seem like they could be real user behavior. Over the past couple years I've been suspecting some kind of automated activity - or possibly someone's MTurk job.
You have seen the quality rater handbook, it's essentially rigged:
"this would be a good match for this query.
Now , based on our guidelines, rank the results for this query." It shows if Google reached its stated goal, not if serps are better to average users.
Maybe they use the number of click in ads, more clicks in ads normally might mean worst SERP quality (with some caveats) and they seek to improve so users get the answers in SERPs based on that.
Or count number of people hitting the back button coupled with the time and compare it?