In short, provisional ratings are averages of the following numbers
opponents rating if you drew
opponents rating + 400 if you won
opponents rating - 400 if you lost.
Originally posted by merman I'm really pissed off at this lose points after winning thing, should I just not play people that are rated lower than me?
You should play anyone you feel like playing, finish up your games and get your true rating. Just because your rating goes down isn't a problem... once you establish your rating more high rated players may want to play you, but I don't feel you should limit yourself yet because you lose a few points for a win.