How is the 'x% fitting' calculated on Netflix?
Nobody here can tell you that. Netflix's recommendation algorithm is one of her big selling points. Not only will they do the hell of making it public, it is unlikely that any of the staff will be able to explain to you, if any, how it works. The calculation gets more and more complex the more input Netflix gets. Accordingly, this is unfortunately not something that can be answered easily.
But is it based on what I'm looking at?
What you look at, what you rate as good, what trailers you may have looked at, i.e. Your personal viewing behavior in combination with the experience that they have gathered from other user profiles.
