Personalization for non logged in users

[PeterRota]

My question is, how does google personalize the search results for non logged in users and incoqnito searches? I already know about the location personalization  whether you're logged in or not and auto complete. But, is personalization still helping in the other cases. Does for example Google keep track of your I.P and then match suggestions that way? Additionally, any other resources would be great.

[FedeEinhorn]

The only personalization Google can make if you are not logged in and have no cookies stored would be using your IP to trace your location. There's no need to keep track of your IP. Every request you make goes with your IP address, a simple IP tracing can reveal lots of information about you: http://tracethisip.com/myip

[PeterRota]

So, if I have cookies stored and i'm logged out. That would probably give more personalized results. Even though I may be logged out?

[FedeEinhorn]

I guess not, at least they shouldn't. But they were caught doing pretty ugly stuff

They could still use your IP to personalize search, there's nothing wrong there.