“N” Backgammon Terms

A tournament of 1-point Nackgammon matches.

[Named after Nack Ballard, who popularized the game.]  A backgammon variant played using the same rules as regular backgammon except for the starting position. Players start with 2 checkers on each of the opponent's one-point and two-point, 4 checkers on the mid-point, 3 checkers on the eight-point, and 4 checkers on the six-point. With fewer checkers up front for attacking, and more checkers back for anchoring and maneuvering, games tend to be longer and more positional. 

[An amalgamation of "Nack" (for Nack Ballard) and "action notation."]  A convenient notation for describing backgammon positions in the first several moves of the game.   See: the Nactation Tutorial for a complete description.

[Also spelled "Nardi" and "Nardy".]  A Russian game similar to Moultezim.   See: How to Play Narde.

[Devised by backgammon expert Neil Kazaross.]  A mnemonic device for estimating match equity (1) based on the current match score. The leader's percent probability of winning the match is 50, plus his point (4) lead in the match multiplied by the appropriate Neil's number. Compare: Janowski's Formula and Turner's Formula.

The architecture used in many of the strongest backgammon programs such as Jellyfish, Snowie, and GNU Backgammon. A neural network consists of many simple processors connected by unidirectional paths carrying numeric data. The network is "trained" by adjusting the weights of the connections until desired outputs are achieved for given inputs.

[From the online match between Kit Woolsey and Readers at GammonU. When the Readers' play is obvious, they are greeted with a link that says "Next" and the game proceeds without a vote.]  A move that is clearly better than the alternatives or obvious enough that it requires no explanation.

Neural network.

Pure race.

An easy decision.

Cocked dice.

A home board with n made points.

A position in which you will bear off all of your checkers in n rolls or less. For example, having ten checkers left on your ace-point is a "5-roll position."