Can someone explain one aspect of ratings calculations to me?  How is an initial provisional rating calculated after four rated games have been completed? 

In the game of Cam, Jannssen has a provisional rating of 2100 after four victories, zero defeats, and zero draws.  Those four victories were against players with ratings of 1341, 1094, and unrated (2 of them).  How is a resultant rating of 2100 possible? 

Let me hasten to add that this is not to cast aspersions on Jannssen's Cam skill level.  For all I know, he is a world-class Cam player.