The value of a position in the context of the current match score and cube level, usually given in terms of match winning chances.

The defensive point (2) you control when playing a holding game, usually the opponent's four-point, five-point, or bar-point. 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.Howell, James (1835). "LXVII. [Letter] To Master G. Stone" in Familiar Letters. Vol. 2. (1850). London: Humphrey Moseley. p.105.

A position which is both a proper double and a correct beaver. This can happen only in money play with the Jacoby rule. By doubling, the underdog gets full value for his potential gammons, thus raising his equity; however, as long as this equity remains negative, the opponent should beaver. The value of a position to one of the players. Equity is the sum of the values of the possible outcomes from a given position with each value multiplied by its probability of occurrence. It is the same as the fair settlement value of the position. Your equity is the negative of your opponent's equity. See post by Gary Wong. Equity comes in different flavors. See: Cubeless Equity, Cubeful Equity, Match Equity, and EMG Equity. Precision Dice Dice which have been carefully cut so their shape and balance are more accurate than regular dice and have pips (1) that are flat and not dimpled. See posts by Patti Beadles and Larry Strommen. The Persian tables game of nard or nardšir emerged somewhere between the 3rd and 6th century AD, one text ( Kār-nāmag ī Ardaxšēr ī Pāpakān) linking it with Ardashir I (r. 224–41), founder of the Sasanian dynasty, whereas another ( Wičārišn ī čatrang ud nihišn ī nēw-ardaxšēr) attributes it to Bozorgmehr Bokhtagan, the vizier of Khosrow I (r. 531–79), who is credited with the invention of the game. [5] Roman and Byzantine Empires [ edit ] Roman Ludus duodecim scriptorum board from the 2nd century, Aphrodisias a b c Tesauro, Gerald (March 1995). "Temporal difference learning and TD-Gammon". Communications of the ACM. 38 (3): 58–68. doi: 10.1145/203330.203343. S2CID 8763243.Any comments, complaints, bug reports, questions, or anything else should be sent to [email protected]. We can't respond to everyone, but we try to Proposed by Danny Kleinman.] A guideline for cube handling in pure race positions. Compute K = (D+4)*(D+4) / (S-4), where D is the player's pip count minus the opponent's count, and S is the sum of the pip counts. Kleinman says a player should make an initial double if K > 0.44, or redouble if K > 0.61, and the opponent should accept a double or redouble if K < 1.2. See post by: Øystein Johansen. An alternative to match play in which two players each begin with a predetermined amount of money or points (4) and play using table-stakes betting until one of them loses everything he started with. See post by Dave Brotherton.

Austin, Roland G. (October 1934). "Roman Board Games. I". Greece & Rome. 4 (10): 24–34. doi: 10.1017/s0017383500002941. S2CID 162861940.A rollout which is not played to the end of the game. Instead, the position is rolled out a given number of plies (the horizon of the rollout) and estimates of the equities of the resulting positions are averaged together. A truncated rollout has more systematic error than a full rollout but is faster because each trial is shorter, and a truncated rollout has less variance so fewer trials are required to converge on a result. See post by Gregg Cattanach. a b Schädler, Ulrich; Dunn-Vaturi, Anne-Elizabeth. "Board Games in pre-Islamic Persia". Encyclopædia Iranica . Retrieved 2018-04-11. To speed up match play and to provide an added dimension for strategy, a doubling cube is usually used. The doubling cube is not a die to be rolled, but rather a marker, with the numbers 2, 4, 8, 16, 32, and 64 inscribed on its sides to denote the current stake. At the start of each game, the doubling cube is placed on the midpoint of the bar with the number 64 showing; the cube is then said to be "centered, on 1". When the cube is still centered, either player may start their turn by proposing that the game be played for twice the current stakes. Their opponent must either accept ("take") the doubled stakes or resign ("drop") the game immediately. A play that leaves no blots, or a play that leaves blots only in positions where the opponent is unlikely to hit. Compare: Bold Play.

A position from which there is only one reasonable game plan for winning, as opposed to a noncommitted position. The second-last round of an elimination tournament; the one that determines the two players who advance to the finals. If you move a piece onto an opposing piece, that piece gets removed and placed onto the middle of the board. The value approached by a rollout as more and more trials are performed. It is the result you would obtain if you could do a rollout an infinite number of times.The game starts with each player throwing one die. The player with the highest number on his die makes the first move (therefore, a game cannot start with a double).