Backgammon Dictionary

A fee charged by a backgammon play site for hosting money games. It is usually a percentage of the winnings of each game.

Variation in the result of a rollout due to chance. It results when the rolls for one side are luckier overall than the rolls for the other side. You can reduce the random error in a rollout by increasing the number of trials.  Compare: Systematic Error.

A numeric value that uniquely determines the sequence of dice rolls produced by a random number generator.

A match that counts towards your rating.

A number associated with each player based on that player's record of performance against other rated players. When you win a match, points are added to your rating; when you lose, points are deducted from your rating. The size of the adjustment depends on the strength of your opponent—the higher the rating of your opponent, the more points you receive. Over time, your rating will tend to be higher than players weaker than yourself, and lower than players stronger than yourself.  See: FIBS rating formula.

Points assigned by a ratings system to players based on their performance against other rated players.

A phenomenon that results when players exit a ratings pool at a lower rating than when they entered. The lost ratings remain with the players still in the pool, giving a higher average rating overall.

The people who participate in a ratings system.

A method of assigning ratings to players based on their performance in such a way that players with greater ability will, over time, tend to have higher ratings.

The minimum game winning chances you need to accept a double if you assume no gammons and no further cube action. The raw take point can be derived from a match equity table and depends only on the score of the match, not on the position. See post by Timothy Chow.   Compare: Take point.

To intentionally allow a blot to be hit for the purpose of gaining time to preserve other valuable points (2).

Redouble.

The value of cube ownership to the player being offered a double; the additional equity that comes from being the only player who may redouble.

A double other than the first double of a game. Only the player who last accepted a double may redouble.  Compare: Initial Double.

Enter a checker from the bar after it has been hit.

A position of known value that serves as a standard by which other similar positions may be measured or judged.  See: Cube Reference Position.

To resign the game at the current stakes after the opponent offers a double rather than continue play at twice the stakes.  Compare: Accept a Double.

To accept defeat. Resignation is a form of settlement; when you resign you must specify whether you are resigning a single game, a gammon, or a backgammon (2), and the opponent must agree. Resigning is not allowed in tournament play before contact is broken.

A chance to hit back after being hit yourself.

Bar.