Computer Backgammon

The first strong computer opponent was BKG 9.8. It was programmed by Hans Berliner in the late 1970s on a PDP-10 as an experiment in evaluating board positions. Early versions of BKG played badly even against poor players, but Berliner noticed that the critical mistakes the program made were always at phase changes. He applied basic principles of fuzzy logic to smooth out the transition between phase changes, and by July 1979, BKG 9.8 was ready to play against then current world champion Luigi Villa. It won the match, 7-1, becoming the first computer program to defeat a world champion in any game, although this was mostly a matter of luck, as the computer happened to get better dice rolls than its opponent in that match.

Beginning in the late 1980s, creators of backgammon-playing software began to have even more success with a neural network approach. TD-Gammon, developed by Gerald Tesauro of IBM, was the first of these computer programs to play at or near the expert level. This program’s neural network was trained using Temporal Difference learning applied to data generated from self-play.

This line of research has resulted in two modern commercial programs, Jellyfish and Snowie, the shareware BGBlitz (implemented in Java), and the free software GNU Backgammon, that play on a par with the best human players in the world. It is worth noting that without their associated “weights” tables which represent hours or even months of tedious neural net training, these programs play no better than a human child.

It is interesting to contrast the development of backgammon software with that of chess software:

For backgammon, neural networks work better than any other methods so far. For chess, brute force searching, with sophisticated pruning and other refinements, works better than neural networks.

Every advance in the power of computer hardware has significantly improved the strength of chess programs. In contrast, additional computing power appears to improve the strength of backgammon software only marginally.

For both backgammon and chess, it is at present unclear whether the best computer or the best human is best overall. For most other games, one or the other is unambiguously stronger.

Greek Tavli Variations for Backgammon Fans

If you’re interested in backgammon you may be interested to know that several different varieties of backgammon exist and are played in different parts of the world. One of these is known as Tavli.

Tavli is a Greek version of backgammon and gets its name from the Greek word for “board”. Three separate games make up Tavli, all offering different rules and sequences of play. However, all three are usually played in sets where players compete in order to win the best of three, five or seven games.

The first version of the game is known as Portes, which bears the most similarities to backgammon as it is commonly played in the western world. Players begin a game of Portes with checkers set up identically to those in a game of regular backgammon. However, players do not use a doubling cube for Portes meaning the game is played for fun rather than money. There is also no backgammon. Instead two points constitute a gammon and a normal win receives one point.

A second Tavli variation is known as Plakoto. The starting point of all checkers in a game of Plakoto deviates from the standard backgammon set up. A player must place his checkers on his opponent’s one point to begin the game and then move them around the board to his home area to bear off. There is also no “hitting” of blots in Plakoto. Instead, if you trap your opponent’s checker on a space it must remain there until you choose to remove your checker. This creates an interesting new twist on the game of backgammon. If your mother checker (the last checker on your starting point) is trapped by your opponent, you automatically lose the game along with two points.

The third Tavli variation known as Fevga also requires players to begin the game with all their checkers on one point on the board. Beginning on the point situated to their far right, each player must move his 15 checkers around the board and bear off once they are safely in his home board area. A major rule in Fevga is that your first checker must pass the point at which your opponent has started before you can move any of your other checkers. Like Plakoto, there is no hitting in the game and one checker is enough to dominate a point. Plakoto strategy differs from regular backgammon as the player is not permitted to erect a prime over six consecutive points. If your opponent gets stuck behind your prime, you are obliged to move a checker to enable him to play on.

While the rules deviate for each Tavli variation, there are some common points you should remember if you’re interested in trying a game. All Tavli games use one set of dice and players must determine who takes the first turn by rolling the dice for a high number. The first player must then roll the dice again to take his turn. One point is awarded to the first player who successfully bears all his checkers off the board. All Tavli variations rely on the enjoyment of the game alone, therefore no doubling cube is used for gambling purposes.

Winning At Backgammon Variant – Plakoto

Plakoto a variant of Backgammon is a popular game in Greece. The motive behind playing Plakoto is to bring all your checkers around to your own home board and then bear them off. The player who bears off all of his checkers first wins the game. This game is usually palyed along with the two other variants of backgammon, namely Fevga and Portes. Together these three games are called Tavli and are played in sequence usually one after the other. They have matches of three, five or seven points. A Bulgarian version of Plakoto is known as Tapa.

Every player has fifteen checkers to start with. These checkers are placed on opponent’s one-point. The players have to move their checkers in different direction on the Plakato board. At the start of the game each player rolls one dice and the player with the highest roll gets the chance to start. Unlike

Backgammon
the player has to again roll the dice to begin his first turn. A player who has won a game starts the next game. The number of points, or pips, or the places a player can move his checkers is decided by the roll of the dice.

In the game of online backgammon Plakoto, a checker can be positioned only on an open point. An open point is the one that is not occupied by two or more checkers of the opponent. The numbers that appear after rolling the two dices make separate moves .For example, if a player rolls 4 and 2, he may move a checker four spaces to an open point and one more checker two spaces to an open point. A player also has an option to move a single checker to a totla of six spaces to an open point the precondition for this single move is that the intermediate points (four or two spaces from the starting point) must also be open.

The doubles in Plakoto are played twice. For example, a roll of 3-3 means that the player can use the three’s four times. If it’s possible the player must use both the numbers of a roll and all four numbers in the case he draws a double in the roll of dices.

Hitting is not allowed in the game of online backgammon Plakoto. In its place, if a player lands on a point occupied by an opponent’s single checker, the opponent cannot move his checker unless the player moves his checker. In other words the opponent’s checker is trapped. A block is created by two checkers of a player lying on a point or one of his checkers pinning the opponent’s checker.

Mother checker is the last checker on a player’s starting point. It is very important to win a online backgammon Plakoto game. If the mother checker gets pinned by opponent’s checker before it has left the starting point – the game is over and two points are lost. This particular rule has an exception if the opponent has his own mother checker at the starting point. A game in which mother checker of both the players are pinned results in a tie.

Bearing off in the game of online backgammon Plakoto starts after a player has moved all of his fifteen checkers on his home board. A player can bear off by rolling a number that corresponds to the point on which the checker is placed. If there is no checker on the point indicated by the roll, then the player has to make a legal move using a checker on a higher-numbered point. If there are no checkers on higher-numbered points, the player must remove a checker from the highest point that has a checker. In this way he can remove all of his checkers from the board

The first player who bears off all his fifteen checkers is declared as the winner of the game. If the losing player has successfully borne off at least one checker, he loses only one point; otherwise two points are lost.

Acey-Deucy Rules for Backgammon Fans

If you’re new to the game of Acey-deucy, the following rules should help get you started playing this simple and fun version of backgammon. If you’re a backgammon enthusiast, you can check out Acey Deucey and start improving your skills before you take on real live opponents.

Acey-ducey shares many similarities with the common game of backgammon. Players begin a game with the same number of checkers and dice. Two home boards on the backgammon board act as the destination to which each player wants to bring his checkers before bearing them off the board altogether.

However, the initial setup of the checkers differs to that in common backgammon rules. Each player must play all of his checkers onto the board instead of starting with them on the board as they do in backgammon. To get checkers onto the board, each player must roll two die. The aim is to get doubles or Acey-deucey, which is when the pip count is one and a two. When a player rolls Ace-deucy, he must move one of his checkers one space and a second checker two spaces. He then receives another turn and must move double (four times) the amount of his choice. A player must move all of his checkers onto the board before he can move those checkers already on the board.

For the purposes of this version of backgammon, a player must roll again each time he rolls a one and a two, or when he rolls doubles. However, several other variants of Acey Deucey exist. One of these stipulates that the player must roll the die again after making acey deucy and use that number to dictate his doubles. Another variant says that if the player cannot move the total amount of doubles after rolling a one and a two, he forfeits his turn.

To make this backgammon game even more difficult, players must roll an exact amount to bear off each checker. If you roll a six and a five, you can only move those checkers that are positioned on your six point and five point, not a checker that is on your four point. This rule can make for some nail-biting finishes. Despite the variations acey-deucy offers on standard backgammon, a player must still be first to remove all of his checkers from his home board in order to win.

Two commonly played versions of Acey-deucy exist; one American and the other European. The American version is thought to have been developed during World War One, where it became popular with sailors and navy personnel. The European version borrowed many of its rules from the American version. Both games are played for fun only, unlike the game of backgammon which is regularly gambled upon. The doubling cube found in backgammon is redundant in Acey Deucey and there are also no points awarded for backgammons or gammons. Instead, the game is considered a pure game of skill due to the difficulties players must face in bearing off exactly and playing all their checkers onto the board before being allowed to move them toward their home boards.