DEC Persona Rules Setup

I am looking at setting up my personas but seem to be not getting it as far as what some of the rules mean.  I found this documentation  with some general info on creating a rule, and I also found this documentation which describes several of the events we are capable of using in our rules.

I still seem to feel confused.  How do I know how a user is tracked as "attend event" or "expand list".  Is there some documentation I am missing?