Scholastic events
are often squeezed for time at the end of the day and tie-breaks are necessary
to determine trophies or other non-cash awards. Tie-breaks systems are not used
for cash prizes; cash prizes are divided evenly among tied players.
Depending on the
size of the event, more than one tie-break system may be needed to determine
the order of finish. The sequence of tie-break systems to be used at a
tournament should be posted before the first round. Unless a different method
has been posted or announced before the first round, USCF rules indicate that
players will expect the following sequence of tie-break systems to be employed
as the first four individual tie-breakers:
1. Modified Median
2. Solkoff
3. Cumulative
4. Cumulative of Opposition
Many of the
primary tie-break systems are based in varying ways on the strength of your
opponents' play. Generally speaking, the stronger the scores of your opponents,
the better your tie-breaks.
The following
tie-break definitions are derived from the U.S. Chess Federation's Official
Rules of Chess, Fourth Edition.
Individual Swiss
tournament tie-break systems
Solkoff
The sum of all opponents' final scores.
Modified Median
·
The sum of opponents' scores (like Solkoff) but
discarding some high or low scores:
- · for players with "plus" scores (more wins than losses) -- the lowest scoring opponent is discarded.
- · for players with "even" scores -- the highest and the lowest scoring opponents are discarded.
- · for players with "minus" scores -- the highest scoring opponent is discarded.
- · For tournaments of nine or more rounds, the top two and bottom two scores are discarded for even score ties, the bottom two scores for plus score ties, and the top two scores for minus score ties.
·
These scores are adjusted for unplayed games
(byes, forfeits, unplayed games), which count a half point each.
Median (Harkness
System)
The sum of opponents' final scores, discarding the highest
and lowest of these scores.
Cumulative
The sum of the cumulative (running) score for each round.
One point is subtracted from the sum for each unplayed win or one-point bye.
For example, if a player's results over a five-round event
were win, loss, win, draw, loss, the wallchart would show a cumulative score
round by round as 1, 1, 2, 2 1/2, 2 1/2. Adding across, the cumulative
tie-break total is 9.
Cumulative Scores of
Opposition
The cumulative tie-break points for each opponent are
calculated and then added together.
Kashdan
A player receives 4 tie-break points for a win, 2 for a
draw, 1 for a loss, and 0 for an unplayed game. This system awards aggressive
play by giving more credit for wins.
Result between Tied
Players
Self-explanatory if two tie, but useful only when they are
paired and did not draw. If more than two tie, all results among tied players
should be considered, with rank according to plus or minus, not percentage (3-1
beats 1-0).
Most Blacks
Self-explanatory.
Opposition's
Performance
This method averages the performance ratings of the players'
opposition. Performance ratings are calculated by crediting the player with the
opponent's rating plus 400 points for a win, the opponent's rating minus 400
points for a loss, and the opponent's rating for a draw. Results of each
opponent against the tied player should not be included, since this would give
the higher-rated tied player an unfair advantage. This system may be difficult
to use when unrated players are in the tournament.
Average Opposition
This system averages the ratings of the players' opponents,
the better tie-break score going to the person who played the highest-rated
average field.
Sonneborn-Berger
(Partial Score Method)
Add the final scores of all the opponents the players
defeated and half the final scores of all the opponents with whom the player
drew. Nothing is added for the games the player lost or for unplayed games.
This is the most common method used for round-robin events.
Modified
Individual/Team tie-break systems
Many scholastic events used a modified individual/team
tournament format. In this type of event, pairings are performed as in a normal
individual Swiss tournament but often teammates (e.g., players from the same
school) will not be paired against each other. At the end of the event, team
points are accumulated (usually the top 4 players' scores are used for the team
calculation) and team awards presented in addition to individual awards. For
this type of tournament, the Team Cumulative tie-break may be employed in the
overall tie-break sequence.
Cumulative
The sum of the cumulative (running) scores for each team
member at the end of the tournament.
Team Cumulative
·
The sum of the cumulative (running) scores for
each team member as the team is defined for each round.
·
This is different from the normal Cumulative
tie-break only if there are more than 4 players on a team and the top 4 scores
involve different sets of players for at least one round.
Most of the individual tie-break systems for individual
Swiss tournaments described above are also suitable for modified
individual/team events.
Team tie-break
systems
In team tournaments, the team competes as a unit against
other teams. The usual example is the 4-board team tournament in which 4 team
members compete in each round against the 4 members of another team. Most of
the individual tie-break systems for individual Swiss tournaments described
above are also suitable for team events. USCF rules describe two other
tie-break systems for team events.
Game (or Match)
Points
U.S. Amateur Team
System
For each round, the final score of the opposing team is
multiplied by the number of points scored against that team. For example, if
Team A scored 2 1/2 - 1 1/2 against Team B, which finished the tournament with
3 match points, Team A's tie-break for that round is 2 1/2 X 3 = 7 1/2.
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