How do the "Bot" apps on Facebook (True Friend Bot, Sex Bot, Crush Bot) calculate who are most likely?

[bonita bohemian]

I think it is both random & defined. Sexbot may randomly pick predefined locations on your facebook profile. I figured this because if I run Sexbot more than once, or over a couple of days (however long it takes for my profile to have different people in different element locations), the result is that the list of people to have sex with changes slightly. I am making the assumption that the list is changing because of expected functionality, and not because there is a bug in the software.

This is merely a marketing tool, this Sexbot application, so I don't think they would want to spend a lot of time or money on it. It is meant to drive Traffic to Sexbot.com, a porn site.