swiss
The swiss system is a fairly complicated pairing system(books have been
written on it). Here is a short summary. For the first round, the players
are ranked by rating. The top player of the top half plays the top player of
the bottom half, the #2 player from the top half plays the #2 player from the
bottom half, and so on. Colors alternate for the top players. A sample first
round pairing for an 8 player tourney would be 1-5, 6-2, 3-7, 8-4. After each
round, the players are sorted again. This time, they are sorted by score in
the tourney(1.0 for each win, 0.5 for each draw, 0.0 for each loss). The
swiss algorithm mentioned above is then applied to each group. As the tourney
goes on, the number of groups(and thus the number of groups with an odd number
of players) grows. There are many techniques used to pair players that are at
least very close in score while avoiding having two players play each other
more than once and giving very lopsided color distribution(for example, having
4 whites and one black in a 5 round tourney) which are beyond the scope of
this short summary. To sum up, you play people who are doing close to as well
(or poorly) as you in the tourney, you play close to an equal number of
games with white as with black, and you don't play the same player twice.
Mamer does its best to make good swiss pairings, but occasionally it will
produce some odd pairings.
[Last modified: September 1, 1998 -- toddmf]