This 2009 question answered by Google’s Matt Cutts dealt with the issue of whether or not Google’s SearchWiki or Analytics data was used for website ranking.
Is SearchWiki or Analytics data used for ranking? –

While interesting to listen to, this particular 2009 question has been rendered partially moot by the 2010 cancellation by Google of the SearchWiki function. Its successor, Google Stars, does not have the same set of capabilities contained in the SearchWiki tool.

Regardless of this, the discussion sheds light on how Google itself is organized. Matt explains that SearchWiki and Analytics are part of the analytic side of Google’s operations. This part of the company is kept segregated from the web search and rating side of Google. This discussion makes the reason quite obvious.

If Google were to start using raw analytical data to adjust their search engine rankings, people would soon be busy poisoning the well of statistical data to suit their own purposes. This would, in turn, render analytical data essentially useless as a factual baseline upon which to make decisions.

As always, Matt emphasizes that people need to take the straight road towards search engine rankings. They need to build a great site that offers real value, rather than spend their days scheming on ways to slip through a crack in the system. There are many sites that generate ad revenue, but they do so by offering something that causes users to visit their site and keep coming back.