While searching today, I noticed that the number of returns on my query was prefaced by “Personalized Results” and I don’t remember turning any such feature on. Had it always been like that and I just hadn’t noticed? This lead me to search for “google personalized” and I was very surprised by what I found. I skipped past the iGoogle result (which was number one) and went straight to the sub-result beneath it titled “Google Web History.” ( I tried iGoogle once…I don’t even remember how long ago. But I didn’t like it so I just stuck with plain old Google as my home page.) Clicking on this link was very enlightening. Google is keeping track of how many searches I perform, which results I visit, how many times I have visited each result, and at what time I did these actions. Then I checked out how much information had been accumulated – everything as far back as May of 2006!! Two years worth of search history available just on me. Imagine how much data they have if you multiple that times the number of Google users. No wonder they need all those server farms.
When I think of the information I can get from Google Analytics, and the information I have seen in my Google Web History, I can’t but help to think that Google is using more parameters and metrics than they are letting on. If you logically combine the information that Google is collecting, it is an entire flow of search sessions. I think of Google as a sea, and each search session as a boat on that sea, and sites as docks in the sea that the boats do or do not stop at. If they can analyze the sites that you frequent and the search terms that you enter, then logically they can create search currents that send you to places that you are more likely to want to go. But this also works in the other direction; the currents could also steer you toward sites *they* want you to be exposed to.
If they are tracking search flows, then the visitors to your site could have an impact on your SERP. For example, let’s say I start a blogger blog about Sea Monkeys, and the leading Sea Monkey expert with a Google account starts to visit my blog once a month. Then the expert starts to visit every week. According to my theory, this would make your rank placement rise. If established experts are given extra ‘weight’ like .gov and .edu links do for PageRank, then your visitors could be given ‘credibility scores’ and influence your SERP.
I cannot prove that the quality of your traffic is being quantified for use in search algorithms. But that doesn’t mean it’s not happening.
Maybe your SERP will be affected by sites that you visit. If I am researching paid link sites or black hat SEO, then I will in all likelihood be visiting some unsavory neighborhoods. If I ‘slum it’ possibly this could reflect badly on the sites I am associated with.
Maybe I’m a paranoid conspiracy theorist. Or maybe not.