How does Google figure out if visitors stayed on the page? Chrome telemetry (creepy)? Google Analytics (are you required to use this to get a good ranking)?
If a user clicks on a link on a search page, stays a few seconds on the new page and then press 'back', and clicks on another link on the search, that's a pretty strong signal to Google that the first link wasn't that good.
Hmmm. If true, I wonder if cmd-clicking the top N links into other tabs can be distinguished or if it's harmful for their ranking. Also, does going back cause a reload?
I'd guess that various clicks in a small time frame can be trivially detected and discarded as noise. The vast majority of the users do not use that pattern.
I don't think it causes a reload, but it can also be trivially detected using JavaScript.
Usage of Google Analytics doesn't affect your PageRank, but it is one way to find out what people that clicked through to your site searched for to find it.