How The Ratings Work
         [with THANKS to SarahT]
 
What the heck are the ratings? I'm so glad you asked! I'll tell you!
 
Every week (a Trivia Week runs from a Sunday night to a Saturday night),
I gather all the game reports from the "Game Results" area. After I
perform many complex mathematical tasks with these results (er,
maybe not complex for most, but just ask Bill about the difficulties
I have with subtraction), I get a ranking of players. There are two
different rankings, the Masters Division and the Open Division. If you
score points in the top seven of 3 or more games during the week, you
qualify for the Masters Division. Score points in the top seven of 2 or
fewer games during the week, and you qualify for the Open Division.
 
For those of you who are dying to know what the complex mathematical
functions are, and you haven't pried it out of Bill already, I'll tell
you.
 
For each game report, I first "cut" the report down so that only the top
seven scorers are listed. Then, I "normalize" the scores for the top seven
players. Normalizing scores makes sure that everyone is on an equal
footing in the ratings no matter what games they have played. To do
this, each person's points are divided by the winning points in the
game:
 
----
SuperHost's SuperGame Score Report:
 7th place with 1 point: SarahT
..
and the winner, 10 points: TomFoster!
----
 
To find out my normalized score for this game, I would divide my points
(1 point) by the winner's points (10) - my normalized score is .10. I do
this for each and every game and each and every player. The winner
always gets a 1.00 and normalized scores always range between 0.01 and
1.00. Triples and pats do not count in any way toward a player's
ratings.
 
Once I have all the games tabulated in this manner, I add up each
person's normalized scores for the week and divide by the number of
games they played to get their "rating."
 
SarahT: .10, .75, 1.00
 
Here, my rating is  (.10 + .75 + 1.00)/3 = .62.
 
Once I've done all the ratings, I divide up the ratings into the
Master's and Open Division and order the players by their rating.
 
And then I have a beer.
 
Those with the highest ratings have "done well" during the Trivia
Week, but we all know that everyone who plays trivia is a winner. ;>
I usually list the top 20 or 30 in my postings, to save space -
usually the cutoff for the listing is a rating of around .40 or so.
 
I used to do this by hand with a calculator and lots of paper, but
I smartened up and now I use a spreadsheet. ;D
 
::officially retiring from the math textbook writing business::