APPENDIX A — Match Scoring and Tie-Breakers

Match points are used for pairing and tie-breakers. Each guild or 1v1 player (hereby know as competitor) earns 3 match points for every match won, 1 point for any draws, and 0 points for any matches lost. Each competitor is assigned an additional 0 to 0.999 match points based on that competitor's opponent's Match-Win Percentage.

Each AT participant's match-win percentage is that competitor's accumulated match points divided by 3, times the number of rounds played, or 0.33, whichever is greater. (Establishing a minimum match-win percentage of 0.33 limits the effect low performances have when calculating and comparing Opponent's Match-Win Percentages.)

For example, a competitor's record is 2-1-1 (2 wins, 1 loss, and 1 draw) after 4 rounds of Swiss play. That competitor has earned 7 match points and has a Match-Win Percentage as follows: 7/(4*3) = .583

A competitor's Opponent's Match-Win Percentage is the average Match-Win Percentage of each opponent that competitor faced (ignoring any rounds for which the competitor received a bye or forfeit).

For example, using the above example, a competitor finished 2-1-1 and its opponents' match records were 2-2-0, 1-2-1, 3-1-0, and 0-4-0, so the competitor's Opponent's Match-Win Percentage is as follows:

(6/12 + 4/12 + 9/12 + 0/12)
4 opponents

Replacing the 0/12 with 0.33 (see above minimum) and translating to the decimal system we get:

(0.50 + 0.33 + 0.67 + 0.33)
4This equation becomes 1.83
4 or 0.46.


This number, which ranges from 0.33 to 1.0 is then scaled to range from 0.0 to 0.999 (for readability) and then added to the competitor's score.

The scaled number is calculated as follows:

(Opponent Win Percentage-0.33) * (0.999/0.67)

In our example above, the competitor has 7.19 points. (7 from its 2 wins and 1 draw, and 0.19 based on an Opponent Win Percentage of 0.46.)

While this may seem a bit complicated, it basically comes down to using the strength of a competitor's schedule as the tie-breaker. The competitor who defeats opponents with better records ends up with a slightly higher score than those competitors who defeated weaker opponents.

Further, each competitor's ladder rank is captured at the start of a tournament. In the event that any ties remain after accounting for Match Points Earned, the ladder rank at the start of the tournament is used to break ties, with better-ranked participants beating worse-ranked guilds (example: a competitor ranked 5th on the ladder beats a competitor ranked 12th on the ladder). http://www.guildwars.com/competitive/tournament2008/rules.php