FACTOID # 2: Puerto Rico has roughly the same gross state product as Montana, Wyoming and North Dakota combined.

 Home Encyclopedia Statistics States A-Z Flags Maps FAQ About

 WHAT'S NEW RELATED ARTICLES People who viewed "Backgammon" also viewed:

SEARCH ALL

FACTS & STATISTICS    Advanced view

Search encyclopedia, statistics and forums:

(* = Graphable)

Encyclopedia > Backgammon
Backgammon

A backgammon set, consisting of a board, two sets of 15 checkers, two pairs of dice, a doubling cube, and dice cups
Players 2
Age range 5+
Setup time 10–30 seconds
Playing time 5–30 minutes
Random chance Dice
Skills required Counting, Tactics, Strategy, Probability

Backgammon is a board game for two players in which the playing pieces[1] are moved according to the roll of dice. A player wins by removing all of his checkers from the board. There are many variants of backgammon, most of which share common traits. Backgammon is a member of the tables family, one of the oldest classes of board games in the world. Image File history File linksMetadata Size of this preview: 800 Ã— 533 pixels Full resolution (1500 Ã— 1000 pixel, file size: 738 KB, MIME type: image/jpeg) File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Backgammon Metadata This file contains... Two standard six-sided pipped dice with rounded corners. ... Counting is the mathematical action of repeatedly adding (or subtracting) one, usually to find out how many objects there are or to set aside a desired number of objects (starting with one for the first object and proceeding with an injective function from the remaining objects to the natural numbers... A tactic is a method employed to help achieve a certain goal. ... A strategy is a long term plan of action designed to achieve a particular goal, most often winning. Strategy is differentiated from tactics or immediate actions with resources at hand by its nature of being extensively premeditated, and often practically rehearsed. ... Probability is the likelihood that something is the case or will happen. ... A board game is a game played with counters or pieces that are placed on, removed from, or moved across a board (a premarked surface, usually specific to that game). ... Two standard six-sided pipped dice with rounded corners. ... Tables is a general name given to a class of board games similar to backgammon, played on a board with two rows of 12 vertical markings called points. Players roll dice to determine the movement of pieces. ...

Although luck plays an important role, there is a large scope for strategy. With each roll of the dice a player must choose from numerous options for moving his checkers and anticipate possible counter-moves by the opponent. Players may raise the stakes during the game. There is an established repertory of common tactics and occurrences.

Like chess, backgammon has been studied with great interest by computer scientists. Owing to this research, backgammon software has been developed capable of beating world-class human players. This article is about the Western board game. ... Computer science, or computing science, is the study of the theoretical foundations of information and computation and their implementation and application in computer systems. ...

## History

Brädspel ("board game") set recovered from the warship Vasa, which sank in 1628.

The ancient Egyptian game senet resembled backgammon,[2] with moves controlled by the roll of dice. However, the Royal Game of Ur, played in ancient Mesopotamia, is a more likely ancestor of modern day tables games. Excavations at the "Burnt City" in Iran have showed that a similar game existed there around 3000 BC. The artifacts include two dice and 60 checkers, and the set is believed to be 100 to 200 years older than the sets found in Ur.[3] Image File history File links Size of this preview: 800 Ã— 600 pixels Full resolution (2592 Ã— 1944 pixel, file size: 2. ... Image File history File links Size of this preview: 800 Ã— 600 pixels Full resolution (2592 Ã— 1944 pixel, file size: 2. ... BrÃ¤dspel is a Swedish variant of backgammon. ... Vasa (or Wasa[2]) is a 64-gun warship, built for Gustavus Adolphus of Sweden 1626-1628. ... The pyramids are the most recognizable symbols of the civilization of ancient Egypt. ... Nefertari playing Senet. ... The Royal Game of Ur refers to two game boards found in Royal Tombs of Ur by Sir Leonard Woolley in the 1920s. ... Mesopotamia was a cradle of civilization geographically located between the Tigris and Euphrates rivers, largely corresponding to modern-day Iraq. ... Shahr-e Sokhte or Shahr-i Sokhta (Persian for burnt city) is an archaeological site of a sizable Bronze Age urban settlement, associated with the Jiroft civilization. ...

The ancient Romans played a number of games remarkably similar to backgammon. Ludus duodecim scriptorum ("Game of twelve lines") used a board with three rows of 12 points each, and the checkers were moved across all three rows according to the roll of dice. Little specific text about the gameplay has survived.[4] Tabula, meaning "table" or "board", was a game mentioned in an epigram of Byzantine Emperor Zeno (AD 476–481). It was similar to modern backgammon in that the object of the game was to be the first to bear off all of one's checkers. Players threw three dice and moved their checkers in opposing directions on a board of 24 points.[5][6] Ancient Rome was a civilization that grew from a small agricultural community founded on the Italian Peninsula circa the 9th century BC to a massive empire straddling the Mediterranean Sea. ... XII scripta board in the museum at Ephesus Ludus duodecim scriptorum, or XII scripta, was a tables game popular during the time of the Roman Empire. ... Medieval illustration of Tabula players (13. ... Byzantine redirects here. ... Flavius Zeno (c. ...

Herr Goeli, from the 14th century Codex Manesse

The jeux de tables, predecessors of modern backgammon, first appeared in France during the 11th century and became a favorite pastime of gamblers. In 1254, Louis IX issued a decree prohibiting his court officials and subjects from playing.[8][9] Tables games were played in Germany in the 12th century, and had reached Iceland by the 13th century. The Alfonso X manuscript Libro de los juegos, completed in 1283, describes rules for a number of dice and tables games in addition to its extensive discussion of chess.[10] By the 17th century, tables games had spread to Sweden. A wooden board and checkers were recovered from the wreck of the Vasa among the belongings of the ship's officers. Backgammon appears widely in paintings of this period, mainly those of Dutch and German painters (Van Ostade, Jan Steen, Bosch and others). One surviving artwork is "Cardsharps" by Caravaggio (The backgammon board is in the lower left.) Others are the Hell of Bosch and interior of an Inn by Jan Steen. Louis IX (25 April 1215 â€“ 25 August 1270), commonly Saint Louis, was King of France from 1226 to his death. ... Alfonso X, El Sabio, or the Learned, (November 23, 1221 - April 4, 1284) was a king of Castile and León (1252 - 1284). ... The Libro de los Juegos, (Book of games), or Libro de ajedrez, dados y tablas, (Book of chess, dice and tables) was commissioned by Alfonso X, king of León and Castile, during the 13th century between 1251 and 1283 AD. It consists of 98 pages, with 150 color illustrations. ... Regalskeppet Vasa (also Wasa) is a Swedish 64-gun ship of the line built for King Gustavus Adolphus of Sweden of the House of Vasa, between 1626 and 1628. ... The Cardsharps (around 1594) is a painting by the Italian Baroque artist Michelangelo Merisi da Caravaggio (1571-1610). ...

In the 16th century, Elizabethan laws and church regulations prohibited playing tables, but by the 18th century backgammon was popular among the English clergy.[8] Edmund Hoyle published A Short Treatise on the Game of Back-Gammon in 1743; this described rules and strategy for the game and was bound together with a similar text on whist.[11] The Elizabethan Era is the period associated with the reign of Queen Elizabeth I (1558 - 1603) and is often considered to be a golden age in English history. ... Edmond Hoyle (sometimes Edmund Hoyle) (1672 - August 29, 1769) Trained to become a barrister, in 1741 Hoyle began working as a Whist tutor to members of high society. ... Whist is a classic trick-taking card game which was played widely in the 18th and 19th centuries. ...

In English, the word "backgammon" is most likely derived from "back" and Middle English "gamen", meaning "game" or "play". The earliest use documented by the Oxford English Dictionary was in 1650.[12] The English language is a West Germanic language that originates in England. ... Middle English is the name given by historical linguistics to the diverse forms of the English language spoken between the Norman invasion of 1066 and the mid-to-late 15th century, when the Chancery Standard, a form of London-based English, began to become widespread, a process aided by the... The Oxford English Dictionary print set The Oxford English Dictionary (OED) is a dictionary published by the Oxford University Press (OUP), and is the most successful dictionary of the English language, (not to be confused with the one-volume Oxford Dictionary of English, formerly New Oxford Dictionary of English, of...

The most recent major development in backgammon was the addition of the doubling cube. It was first introduced in 1926 or 1927 in New York City among members of gaming clubs in the Lower East Side.[13] The cube required players not only to select the best move in a given position, but also to estimate the probability of winning from that position, transforming backgammon into the expected value-driven game played in the 20th and 21st centuries.[13] New York, New York and NYC redirect here. ... Categories: Manhattan neighborhoods | Stub ... In probability theory the expected value (or mathematical expectation) of a random variable is the sum of the probability of each possible outcome of the experiment multiplied by its payoff (value). Thus, it represents the average amount one expects as the outcome of the random trial when identical odds are...

## Rules

Paths of movement for red and black, with checkers in the starting position

The objective of backgammon is to move all of one's own checkers past those of one's opponent and then remove them from the board. The checkers are scattered at first and may be blocked or hit by the opponent. As the playing time for each individual game is short, it is often played in matches, where victory is awarded to the first player to reach a certain number of points. Image File history File links This is a lossless scalable vector image. ... Image File history File links This is a lossless scalable vector image. ...

### Setup

Each side of the board has a track of 12 long triangles, called points. The points are considered to be connected across one edge of the board, forming a continuous track in the shape of a horseshoe, and are numbered from 1 to 24. Each player begins with two checkers on his 24-point, three checkers on his 8-point, and five checkers each on his 13-point and his 6-point. The two players move their checkers in opposing directions, each from his own 24-point towards his 1-point.[14] For other uses, see Horseshoe (disambiguation). ...

Points 1 through 6 are called the home board or inner board, and points 7 through 12 are called the outer board. The 7-point is referred to as the bar point, and the 13-point as the mid point.[14][15]

### Movement

A Short Treatise on the Game of Backgammon, by Edmond Hoyle

To start the game, each player rolls one die, and the player with the higher number moves first using both the numbers shown. Both dice must land completely flat on the right hand side of the gameboard. The players then alternate turns, rolling two dice at the beginning of each turn.[14][15] Image File history File links Size of this preview: 304 Ã— 600 pixels Full resolution (1092 Ã— 2154 pixel, file size: 47 KB, MIME type: image/png) Faithful reproductions of two-dimensional original works cannot attract copyright in the U.S. according to the rule in Bridgeman Art Library v. ... Image File history File links Size of this preview: 304 Ã— 600 pixels Full resolution (1092 Ã— 2154 pixel, file size: 47 KB, MIME type: image/png) Faithful reproductions of two-dimensional original works cannot attract copyright in the U.S. according to the rule in Bridgeman Art Library v. ...

After rolling the dice a player must, if possible, move his checkers according to the number of pips shown on each die. For example, if the player rolls a 6 and a 3 (noted as "6-3"), that player must move one checker six points forward, and another checker three points forward. The same checker may be moved twice as long as the two moves are distinct: six and then three, or three and then six, but not all nine at once. If a player rolls two of the same number, called doubles, that player must play each die twice. For example, upon rolling a 5-5 that player must move four checkers forward five spaces each. It can sometimes happen that a player can not play his entire roll, in which case as much of the roll as possible must be used. For example if a player rolls 6-3 and can only move a 6 or a 3, the 6 being the bigger number must be moved; if it is possible to move the 3 but not the 6 then the 3 is played.[14][15]

In the course of a move, a checker may land on any point that is unoccupied or is occupied only by a player's own checkers. It may also land on a point occupied by exactly one opposing checker; such a lone piece is called a blot. In this case, the blot has been hit, and is placed in the middle of the board on the bar that divides the two sides of the playing surface. A checker may never land on a point occupied by two or more opposing checkers; thus, no point is ever occupied by checkers from both players simultaneously.[14][15]

Checkers placed on the bar re-enter the game through the hitting player's home board. A roll of 2 allows the checker to enter on the 23-point, a roll of 3 on the 22-point, and so forth. A player may not move any other checkers until all checkers on the bar belonging to that player have re-entered the game.[14][15]

When all of a player's checkers are in the player's home board, that player may start removing them; this is called bearing off. A roll of 1 may be used to bear off a checker from the 1-point, a 2 from the 2-point, and so on. A die may not be used to bear off checkers from a lower-numbered point unless there are no checkers on any higher points.[14][15] For example if a player rolls a 6 and a 5, but has no checkers on the 6-point, though 2 checkers remain on the 5-point, then the 6 and the 5 must be used to bear off the 2 checkers from the 5-point. When bearing off, a player may also move a lower die roll before the higher even if that means 'the full value of the higher die' is not fully utilized. In other words, if a player has exactly 1 checker remaining on the 6-point, and rolls a 6 and a 1, the player may move the 6-point checker 1 place to the 5-point with the lower die roll of 1, and then bear that piece off the 5-point using the die roll of 6, this is sometimes useful tactically.

If one player has not borne off any checkers by the time that player's opponent has borne off all fifteen, then the player has lost a gammon, which counts for double a normal loss. If the losing player has not borne off any checkers and still has checkers on the bar or in the opponent's home board, then the player has lost a backgammon, which counts for triple a normal loss.[14][15]

### Doubling cube

Doubling cube

The game is rarely redoubled beyond four times the original stake, but there is no limit on the number of doubles. Although 64 is the highest number depicted on the doubling cube, the stakes may rise to 128, 256, and so on. In money games, a player is often permitted to "beaver" when offered the cube, doubling the value of the game again, while retaining possession of the cube.[16]

Some money games use the "automatic double" rule. If both opponents roll the same opening number, the doubling cube is incremented on each occasion yet remains in the middle of the board, available to either player. When a player decides to double his opponent, the value is then a double of whatever face value is shown (e.g. if two automatic doubles have occurred putting the cube up to 4, the first in-game double will be for 8 points).

A variant of the doubling cube "beaver" is the "raccoon". The player who doubled his opponent, seeing him beaver the cube, may in turn then double the stakes once again as part of that cube phase before any dice are rolled. His opponent retains the doubling cube. E.g. White doubles Black to 2 points, Black accepts then beavers the cube to 4 points; White, confident of a win, raccoons the cube to 8 points, whilst Black retains the cube. Such a move adds greatly to the risk of having to face the doubling cube coming back at 8 times its original value when first doubling the opponent (offered at 2 points, counter offered at 16 points) should the luck of the dice change.

The Jacoby rule allows gammons and backgammons to count for their respective double and triple values only if the cube has already been offered and accepted. This encourages a player with a large lead to double, possibly ending the game, rather than to play it to conclusion hoping for a gammon or backgammon. The Jacoby rule is widely used in money play but is not used in match play.[17]

The Crawford rule is designed to make match play more equitable for the player in the lead. If a player is one point away from winning a match, that player's opponent will always want to double as early as possible in order to catch up. Whether the game is worth one point or two, the trailing player must win to continue the match. To balance the situation, the Crawford rule requires that when a player first reaches a score one point short of winning, neither player may use the doubling cube for the following game, called the Crawford game. After the Crawford game, normal use of the doubling cube resumes. The Crawford rule is used in tournament match play.[17]

### Variants

Todas tablas from the Libro de los juegos
Main article: Tables (board game)

There are many variants of standard backgammon rules. Some are played primarily throughout one geographic region, and others add new tactical elements to the game. Variants commonly alter the starting position, restrict certain moves, or assign special value to certain dice rolls, but in some geographic regions even the direction of the pieces and rules change, rendering the game fundamentally different. Image File history File links No higher resolution available. ... Image File history File links No higher resolution available. ... The Libro de los Juegos, (Book of games), or Libro de ajedrez, dados y tablas, (Book of chess, dice and tables) was commissioned by Alfonso X, king of León and Castile, during the 13th century between 1251 and 1283 AD. It consists of 98 pages, with 150 color illustrations. ... Tables is a general name given to a class of board games similar to backgammon, played on a board with two rows of 12 vertical markings called points. Players roll dice to determine the movement of pieces. ...

A common simple variant of Backgammon is to only allow a maximum of five checkers on any point. This variation is not part of the official rules, but has proved popular with casual players in some regions [18]. The popular GNU Backgammon software has an option for this, which is described as the 'Egyptian Rule', however the origin of that name might be due to a humorous invention.[19]

Acey-deucey is a variant of backgammon in which players start with no checkers on the board, and must bear them on at the beginning of the game. The roll of 1-2 is given special consideration, allowing the player, after moving the 1 and the 2, to select any doubles move of his choice. A player also receives an extra turn after a roll of 1-2 or of doubles. Acey-Deucey is a backgammon variant with different starting, ending, and doubles rules. ...

Hypergammon is a variant of backgammon in which players have only three checkers on the board, starting with one each on the 24-, 23- and 22-points. The game has been strongly solved, meaning that exact equities are available for all 32 million possible positions.[20][21] A two player game can be solved on several levels [1] [2]: Ultra-weak In the weakest sense, solving a game means proving whether the first player will win, lose, or draw from the initial position, given perfect play on both sides. ... In probability theory the expected value (or mathematical expectation) of a random variable is the sum of the probability of each possible outcome of the experiment multiplied by its payoff (value). Thus, it represents the average amount one expects as the outcome of the random trial when identical odds are...

Nackgammon is a variant of backgammon invented by Nack Ballard in which players start with one fewer checker on the six point and midpoint and two checkers on the 23 point.[21][22]

## Strategy and tactics

Backgammon set, 19th century

Backgammon has an established opening theory, although it is less detailed than that of games like chess. The tree of positions expands rapidly because of the number of possible dice rolls and the moves available on each turn. Recent computer analysis has offered more insight on opening plays, but the midgame is reached quickly. After the opening, backgammon players frequently rely on some established general strategies, combining and switching among them to adapt to the changing conditions of a game. Backgammon-set from American civil war From http://www. ... Backgammon-set from American civil war From http://www. ... The first moves of a backgammon game are the opening moves, collectively referred to as the opening, and studied in the backgammon opening theory. ... In game theory, a game tree is a directed graph whose nodes are positions in a game and whose edges are moves. ...

The most direct strategy is simply to avoid being hit, trapped, or held in a stand-off. A "running game" describes a strategy of moving as quickly as possible around the board, and is most successful when a player is already ahead in the race.[23] When this fails, one may opt for a "holding game", maintaining control of a point on one's opponent's side of the board, called an anchor. As the game progresses, this player may gain an advantage by hitting an opponent's blot from the anchor, or by rolling large doubles that allow the checkers to escape into a running game.[23]

The "priming game" involves building a wall of checkers, called a prime, covering a number of consecutive points. This obstructs opposing checkers that are behind the prime. A checker trapped behind a six-point prime may not escape until the prime is broken.[23] A particularly successful priming effort may lead to a "blitz", which is a strategy of covering the entire home board as quickly as possible while keeping one's opponent on the bar. Because the opponent has difficulty re-entering from the bar or escaping, a player can quickly gain a running advantage and win the game, often with a gammon.[14]

A "backgame" is a strategy of placing two or more anchors in an opponent's home board, while building a prime in one's own board. The anchors obstruct the opponent's checkers and create opportunities to hit them as they move home. The backgame is generally used only to salvage a game wherein a player is already significantly behind; using a backgame as an initial strategy is usually unsuccessful.[14][23]

"Duplication" refers to the placement of checkers such that one's opponent needs the same dice rolls to achieve different goals. For example, a player may position all of his blots in such a way that his opponent must roll a 2 in order to hit any of them, reducing the probability of being hit.[14][23] "Diversification" refers to a complementary tactic of placing one's own checkers in such a way that more numbers are useful.[23]

Many positions require a measurement of a player's standing in the race, for example, in making a doubling cube decision, or in determining whether to run home and begin bearing off. The minimum total of dice rolls needed to move a player's checkers around and off the board is called the "pip count". The difference between the two players' pip counts is frequently used as a measure of the leader's racing advantage. Players often use mental calculation techniques to determine pip counts in live play.[23] Mental calculation is the practice of doing mathematical calculations using only the human brain, with no help from any computing devices. ...

## Social and competitive play

Medieval players, from the 13th century Carmina Burana

Image File history File links Wurfzabel, Tabula game (Wurfzabelspieler (13. ... Image File history File links Wurfzabel, Tabula game (Wurfzabelspieler (13. ... Carmina Burana (IPA: ; note that the stress is on the first syllable of Carmina, not the second) also known as the Burana Codex is a manuscript collection, now in the Bayerische Staatsbibliothek in Munich, of more than 1000 poems and songs written in the early 13th century. ...

### Club and tournament play

Enthusiasts have formed clubs for social play of backgammon. Local clubs may hold informal gatherings, with members meeting at cafés and bars in the evening to play and converse.[24][25] A few clubs offer additional services, maintaining their own facilities or offering computer analysis of troublesome plays.[26] Some club leaders have noticed a recent growth of interest in backgammon, and attribute it to the game's popularity on the internet.[27] This article does not cite any references or sources. ...

A backgammon chouette permits three or more players to participate in a single game, often for money. One player competes against a team of all the other participants, and positions rotate after each game. Chouette play often permits the use of multiple doubling cubes.[14] The Backgammon Chouette is a social, multi-player form of backgammon and was mostly played socially with a number of players conversing and playing against each other on the same table. ...

Backgammon clubs may also organize tournaments. Large club tournaments sometimes draw competitors from other regions, with final matches viewed by hundreds of spectators.[28] The top players at regional tournaments often compete in major national and international championships. Winners at major tournaments may receive prizes of tens of thousands of dollars.[29] A tournament is an organized competition in which many participants play each other in individual games. ... The United States dollar is the official currency of the United States. ...

### International competition

Prior to 1979, there was no single world championship competition in backgammon, although a number of major tournaments were held in Las Vegas, Nevada and the Bahamas. Since 1979, the World Backgammon Championship in Monte Carlo has been widely acknowledged as the top international tournament.[30] The Monte Carlo tournament draws thousands of players and spectators, and is played over the course of a week.[29] For further information, see Las Vegas metropolitan area and Las Vegas Strip. ... Monte Carlo is a very wealthy section of the city-state of Monaco known for its casino, gambling, beaches, glamour, and sightings of famous people. ...

By the 21st century, the largest international tournaments had established the basis of a tour for top professional players. Major tournaments are held yearly in St. Tropez, Rio de Janiero, Dallas, and Venice.[17] PartyGaming sponsored a tournament in the Bahamas in January 2007 with a prize pool of one million dollars, the largest for any tournament to date.[31] Saint-Tropez is a commune of the Var département in southern France, located on the French Riviera. ... Ipanema beach A NASA satellite image of Rio de Janeiro Rio de Janeiro (meaning River of January in Portuguese) is the name of both a state and a city in southeastern Brazil. ... Dallas redirects here. ... For other uses, see Venice (disambiguation). ... PartyGaming Plc (LSE: PRTY) is an online gambling company, best known for its online poker room PartyPoker. ... [--168. ...

### Gambling

When backgammon is played for money, the most common arrangement is to assign a monetary value to each point, and to play to a certain score, or until either player chooses to stop. The stakes are raised by gammons, backgammons, and use of the doubling cube. Backgammon is sometimes available in casinos. As with most gambling games, successful play requires a combination of luck and skill, as a single dice roll can sometimes significantly change the outcome of the game. [23] Gamble redirects here. ... This article or section does not adequately cite its references or sources. ...

## Software

### Play and analysis

A screen shot of GNU Backgammon, showing an evaluation and rollout of possible moves

The first strong computer opponent was BKG 9.8. It was written by Hans Berliner in the late 1970s on a DEC PDP-10 as an experiment in evaluating board game positions. Early versions of BKG played badly even against poor players, but Berliner noticed that its critical mistakes were always at transitional phases in the game. He applied principles of fuzzy logic to improve its play between phases, and by July 1979, BKG 9.8 was strong enough to play against the ruling world champion Luigi Villa. It won the match, 7–1, becoming the first computer program to defeat a world champion in any board game. Berliner stated that the victory was largely a matter of luck, as the computer received more favorable dice rolls.[32] Hans Jack Berliner (born January 27, 1929) Professor of Computer Science at Carnegie Mellon University, is a former World Correspondence Chess Champion. ... The PDP-10 was a computer manufactured by Digital Equipment Corporation (DEC) from the late 1960s on; the name stands for Programmed Data Processor model 10. It was the machine that made time-sharing common; it looms large in hacker folklore because of its adoption in the 1970s by many... Fuzzy logic is derived from fuzzy set theory dealing with reasoning that is approximate rather than precisely deduced from classical predicate logic. ... Luigi Villa is a backgammon player from Milan, Italy. ...

In the late 1980s, backgammon programmers found more success with an approach based on artificial neural networks. TD-Gammon, developed by Gerald Tesauro of IBM, was the first of these programs to play near the expert level. Its neural network was trained using temporal difference learning applied to data generated from self-play.[33] According to assessments by Bill Robertie and Kit Woolsey, TD-Gammon's play was at or above the level of the top human players in the world.[33] Woolsey said of the program that "There is no question in my mind that its positional judgment is far better than mine."[33] For other uses, see IBM (disambiguation) and Big Blue. ... Temporal difference learning is a prediction method. ... Bill Robertie is a backgammon, chess and poker player and author. ... Kit Woolsey (born 1943) is a world class bridge player as well as one of the top backgammon players in the world. ...

Neural network research has resulted in two modern commercial programs, Jellyfish[34] and Snowie[35] as well as the shareware BGBlitz[36] and the free software GNU Backgammon.[37] These programs not only play the game, but offer tools for analyzing games and offering detailed comparisons of individual moves. The strength of these programs lies in their neural networks' weights tables, which are the result of months of training. Without them, these programs play no better than a human novice. For the bearoff phase, backgammon software usually relies on a database containing precomputed equities for all possible bearoff positions. Proprietary software is software with restrictions on copying and modifying as enforced by the proprietor. ... Look up shareware in Wiktionary, the free dictionary. ... Free software is software that can be used, studied, and modified without restriction, and which can be copied and redistributed in modified or unmodified form either without restriction, or with minimal restrictions only to ensure that further recipients can also do these things. ...

### Internet play

Backgammon software has been developed not only to play and analyze games, but also to facilitate play between humans over the internet. Dice rolls are provided by random or pseudorandom number generators. Real-time online play began with the First Internet Backgammon Server in 1992.[38] It is the longest running non-commercial backgammon server and retains an international community of backgammon players. Yahoo Games offers a Java-based online backgammon room, and MSN Games offers a game based on ActiveX. Online gambling providers began to expand their offerings to include backgammon in 2006.[39] A random number generator is a computational or physical device designed to generate a sequence of elements (usually numbers), such that the sequence can be used as a random one. ... A pseudorandom number generator (PRNG) is an algorithm to generate a sequence of numbers that approximate the properties of random numbers. ... First Internet Backgammon Server (FIBS) is the earliest backgammon server on the internet, operating since July 19, 1992. ... Yahoo! Games is the games section of the Yahoo! website. ... MSN Games (also known as Zone. ... ActiveX control is a term used to denote reusable software components that are based on Microsoft Component Object Model (COM). ... Online gambling is a general term for gambling using the Internet. ...

### Backgammon in popular culture

The fictional super spy character James Bond (portrayed by Roger Moore) plays Backgammon for a Faberge egg against the chief villain Kamal Khan in the 1983 film Octopussy Image File history File links Broom_icon. ... Look up trivia in Wiktionary, the free dictionary. ... In fiction, a plot is all the events in a story particularly rendered towards the achievement of some particular artistic or emotional effect. ... This article is about the spy series. ... For other persons named Roger Moore, see Roger Moore (disambiguation). ... Fabergé may refer to: Peter Carl Fabergé, the jeweler House of Fabergé, his firm Fabergé eggs, his most famous works Fabergé line of Victor Mayer This is a disambiguation page — a navigational aid which lists other pages that might otherwise share the same title. ... Kamal Khan is a fictional character and villain in the James Bond film Octopussy. ... For other uses, see Octopussy (disambiguation). ...

Wikibooks has more on the topic of
Backgammon
Wikisource has original text related to this article:
Backgammon
Wikimedia Commons has media related to:
Backgammon
Look up Transwiki:Backgammon glossary in
Wiktionary, the free dictionary.

Image File history File links Wikibooks-logo-en. ... Wikibooks logo Wikibooks, previously called Wikimedia Free Textbook Project and Wikimedia-Textbooks, is a wiki for the creation of books. ... Image File history File links Wikisource-logo. ... The original Wikisource logo. ... Image File history File links Commons-logo. ... Wiktionary (a portmanteau of wiki and dictionary) is a multilingual, Web-based project to create a free content dictionary, available in over 151 languages. ... Backgammon notation is a means for recording backgammon games, developed by Paul Magriel in the 1970s. ...

## Notes and references

1. ^ Backgammon playing pieces are known variously as stones, men, counters, pawns, checkers, or chips.
2. ^ Hayes, William C. (March 1946.). ""Egyptian Tomb Reliefs of the Old Kingdom"". The Metropolitan Museum of Art Bulletin New Series 4 (7): 170-178.
3. ^ "Iran's Burnt City Throws up World’s Oldest Backgammon", Persian Journal, December 4, 2004. Retrieved on 2006-08-05.
4. ^ Austin, Roland G. (October 1934). "Roman Board Games. I". Greece & Rome 4 (10): 24-34.
5. ^ Austin, Roland G. (February 1935). "Roman Board Games. II". Greece & Rome 4 (11): 76-82.
6. ^ Austin, Roland G (1934). "Zeno's Game of τάβλη". The Journal of Hellenic Studies 54 (2): 202-205.
7. ^ Wilkinson, Charles K (May 1943). "Chessmen and Chess". The Metropolitan Museum of Art Bulletin New Series 1 (9): 271-279.
8. ^ a b c Murray, Harold James Ruthven (1952). "6: Race-Games", A History of Board-Games Other than Chess. Hacker Art Books. ISBN 0-87817-211-4.
9. ^ Lillich, Meredith Parsons (March 1983). "The Tric-Trac Window of Le Mans". The Art Bulletin 65 (1): 23-33.
10. ^ Wollesen, Jens T (1990). "Sub specie ludi...: Text and Images in Alfonso El Sabio's Libro de Acedrex, Dados e Tablas". Zeitschrift für Kunstgeschichte 53 (3): 277-308.
11. ^ Allee, Sheila. "A Foregone Conclusion: Fore-Edge Books Are Unique Additions to Ransom Collection", The University of Texas at Austin. Retrieved on 2006-08-08.
12. ^ (1989) ""backgammon"". The Oxford English Dictionary, Second Edition. Retrieved on 2006-08-05.
13. ^ a b Robertie, Bill (2002). 501 Essential Backgammon Problems, Second Printing, Cardoza, 22. ISBN 1-58042-019-2.
14. ^ a b c d e f g h i j k l m Robertie, Bill (2002). Backgammon for Winners, Third Edition, Cardoza. ISBN 1-58042-043-5.
15. ^ a b c d e f g h (2001) Hoyle's Rules of Games, Third Revised and Updated Edition, Signet, 321-330. ISBN 0-451-20484-0.
16. ^ Robertie, Bill. Backgammon Beavers. GammonVillage. Retrieved on 2007-10-17.
17. ^ a b c Robertie, Bill (2006). Backgammon for Serious Players, Second Edition, Cardoza, 19-22. ISBN 0-940685-68-X.
18. ^ Discussion at bkgm.com
19. ^ IRC archive that contains (when searched) a discussion of how the name originated at aqsis.org
20. ^ Tesauro, G. (2002). "Programming backgammon using self-teaching neural nets". Artificial Intelligence 134 (1): 181-199. Retrieved on 2007-08-08.
21. ^ a b Strato, Michael. Backgammon Variants. Gammonlife. Retrieved on 2007-08-08.
22. ^ Woolsey, Kit (September 2001). Nackgammon. Gammonline. Retrieved on 2007-08-08.
23. ^ a b c d e f g h Magriel, Paul (1976). Backgammon. Quadrangle/The New York Times Book Co. ISBN 0-8129-0615-2.
24. ^ "Tribes of Sydney — Sydney Backgammon Club", The Daily Telegraph (Australia), June 24, 2006, pp. 95.
25. ^ Bray, Chris. "Backgammon", The Independent (London), June 29, 2002, pp. 50.
26. ^ Bray, Chris. "Backgammon", The Independent (London), November 25, 2000, pp. 19.
27. ^ Laverty, Roy. "Backgammon warriors — columnist, club member square off as board game's popularity grows", The Alameda Times-Star (Section: Bay Area Living), May 16, 2003.
28. ^ Magriel, Paul. "Backgammon: Before Planning Big Attack, Be Sure to Cover Your Rear", The New York Times, Late City Final Edition, June 1, 1980, pp. 50, section 1, part 2.
29. ^ a b Maxa, Rudy. "Where the Rich And the Royal Play Their Games — Monte Carlo's Seven-Day Backgammon Soiree With Countesses, Princes and Other Sharpies", The Washington Post, September 6, 1981, pp. H1.
30. ^ Michael Crane (July 25, 2000). Backgammon News — World Championships 2000. Mind Sports Worldwide. Retrieved on 2006-09-14.
31. ^ "PartyGammon.com to Stage First Ever US\$1 Million Backgammon Tournament", PR Newswire, Lexis-Nexis, July 10, 2006. Retrieved on 2006-08-12.
32. ^ Berliner, Hans; et al. (January 1980). "Backgammon program beats world champ". ACM SIGART Bulletin (69): 6-9.
33. ^ a b c Tesauro, Gerald (March 1995). "Temporal difference learning and TD-Gammon". Communications of the ACM 38 (3): 58-68.
34. ^ Jellyfish
35. ^ Snowie,
36. ^ BGBlitz
37. ^ GNU Backgammon.
38. ^ Schneider, Andreas; et al.. Brief history of FIBS. FIBS, the First Internet Backgammon Server. Retrieved on 2006-08-05.
39. ^ Lemke, Tim. "Odds favor Internet gambling — Lawmakers aim to rein in industry", The Washington Times, March 19, 2006, pp. A1.

Results from FactBites:

 Play Backgammon Online! Backgammon Games, Rules, Tips, and much more. (2529 words) Backgammon is an obstacle race between two armies of 15 men each, moving around a track divided into 24 dagger-like divisions known as ``points''. The Backgammon layout is divided down the center by a partition, known as the ``bar'' (See Diagram 1), into an outer and inner (or home) board or table. The object of Backgammon is for each player to bring all his men into his home board, and then to bear them off the board.
 Backgammon - Wikipedia, the free encyclopedia (4867 words) Backgammon is a board game for two players in which pieces are moved according to the roll of dice and the winner is the first to remove all his pieces from the board. When backgammon is played for money, the most common arrangement is to assign a monetary value to each game, with the stakes raised by the doubling cube, gammons, and backgammons, and to play until a certain score is reached. Matches in the World Backgammon Championship start at 17 points, and are 19 points in the round of 16, 21 points in the quarterfinals, 23 points in the semifinals, and 25 points in the finals.
More results at FactBites »

Share your thoughts, questions and commentary here