Here's a report that was supposedly "leaked" from Google that details how real humans hired by Google are to rank web pages.

http://www.mauriziopetrone.com/blog/wp-content/uploads/quality-rater-guidelines-2007.pdf

Even if you don't have time to read it now, I suggest you download it as it may dissapear in the future.

Whether this is an official Google document is irrelevant IMO. What is important is the way the document teaches how to judge relevancy, as well as spam.

While some claim the document is fake, it does contain a number of facts that are exactly the same as Google has published in other documents.

Those that have been Bombers for a while know that I have a concept I call "People Rank", which is a combo of hired reviewers as well as the SE tracking searcher actions...This document adds to my theory.