Swiss Pairings

Table of Contents: Points | Pairs | Glossary | Related Links

Points

Some KGS Tournaments use the Swiss pairing system. In the Swiss system, you either play or get a bye in every round; when you lose, you are not dropped from the tournament. You get a point for every win and a half point for every bye. The player with the most points wins. If there is a tie for the most points, the tie is broken by your SOS, which is the sum of the scores of all your opponents. If there is still a tie, it is broken by your SODOS, which is the sum of the scores of all opponents you defeated.

Pairs

In every round the tournament, the system pairs the players. As in all KGS tournaments, these pairings are fully automated. The pairing system trys to achieve the following goals.

Avoid pairing players who have played each other already.
Attempt to pair players with the highest score.
Attempt to keep handicaps low (only in handicap tournaments; in non-handicap tournaments, your ranks are completely ignored).

These goals are not absolute, instead they are balanced against each other. If the two players with the best scores have already played each other and/or would need high handicaps to play anybody else, the pairing system may decide to pair them a second time. In addition, if there are an odd number of players, the system is forced to give somebody a bye. It tries to select a player with a low score, but it also tries to avoid giving the same person multiple byes.

On the first round, you have just as good a chance to be paired with

the strongest player in the tournament
a player close to your own strength
the weakest player in the tournament

as with any other.

Glossary

SODOS
Sum Of Defeated Opponents' Scores
SOS
Sum of Opponents' Scores