Sonneborn-Berger

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Sonneborn-Berger Tie Break System

The Sonneborn-Berger is similar to the Solkoff except that opponents scores are also adjusted by multiplying them by the result acheived in the game.

Scores of players tied with the same tournament score (1 point for a win, 1/2 point for a draw and no points for a loss) can be sorted by using the Sonneborn-Berger system.

First make a list of the opponents adjusted scores for the tournament - unplayed games are cocunted as draws, whether they are scored as wins or losses for tournament standings. An opponents unplayed game against other opponents are scored as a loss.

Then total the opponents adjusted scores to determine the Solkoff tie-break. The highest Solkoff score is the tie-break winner. Note that tie-break systems only sort the players rank within the tournament score group and cannot catapult a player with a lower tournament score over a player with a higher score.

Examples

Example 1: Player A & B both score 3 wins and 2 losses. Player A played games with opponetns who scored 1, 3, 2, 2,& 2 with wins against the first three. Player B played opponetns who scored 1, 2, 2, 2 & 2 and also scored wins against the first three. Player A woud have a Sonneborn-Berger tie-break of 6 (1*1+3*1+2*1+2*0+2*0) and Player B would have a Sonneborn-Berger tie-break of 5 (1*1+1*2+1*2+0*2+0*2).

Example 2: In this example, we'll again assume 3 points for each player, this time in rounds 1, 3 and 5. Both players have the same opponents scores, but Player A, won one game on forfeiture. When calculating that players score, a zero in scored for that round. So if a Player A was paired with opponents of 1,3,2,2,2 and his ;last round opponent left early and so the player was awarded a win on a forfeit, his tie-break would be calculated as 1*1+0*3+1*2+0*2+1*0=3. Player B scored 5 S-B tie break points (1*1+0*2+1*2+0*2+1*2).

Example 3: In this example, we'll again assume 3 points for each player in rounds 1, 3 and 5. Both players have the same opponents scores and played all their games, but one Player A opponent won one game on forfeiture. When calculating that players score, a half point in scored for the unplayed round of the opponent. So if a player was paired with opponents of 1,3,2,2,2 but his last round opponent was awarded a win on a forfeit, the opponets adjusted score would be calculated as 1.5, instead of 2 and Player A's Sonneborn-Berger tie-break would be 4.5 (1*1+0*3+1*2+0*2+1*1.5). Player B's score would be determined as above.