How does the DCI compute my rating?

[jazzykat]

Well, I lost a game today to a friend who was 100 points below me, but I beat 4 people all of which I was 200 points above. The tournament was 16K. I was told some things about how my rating will be computed and my guess is that I will be net -2 points on the evening.

Is there a place that states how your rating is computed?

Thanks.

[Nihil Credo]

http://en.wikipedia.org/wiki/Elo_rating_system#Theory

[RoddyVR]

Wierd. From that page i gather that who i win or lose against in a tournament doesnt matter. Its my record in the tourny and the average/total ratings of all my opponents combined that matter?

So going 2-2 in a 4 round tourny, playing against 2 people with insanely high ratings and 2 with realy low ratings, it doesnt matter which 2 i beat and which two beat me?

Also, does any one know if the DCI counts games or matches for their Win/Loss calculations? is a 2-1 match win the same as a 2-0 win or does that game loss in game 2 affect ratings too?

[Van Phanel]

Nope.

For magic each the rating change is calculated seperately for each game you play.

2-1 or 2-0 doesn't matter for rating, only for tiebreakers.