Backgammon according to the normal movement rules. The first player to bear off all fifteen of his/her own checkers wins the game. If the opponent has not yet borne off any checkers when the game ends, the winner scores a "gammon", which counts for double stakes. If the opponent has not yet borne off any checkers and has some on the bar or in the winner's home board, the winner scores a "backgammon", which counts for triple stakes. To speed up match play and to provide an added dimension for strategy, a doubling cube is usually used. The doubling cube is
Backgammon against the reigning 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. 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. According to assessments by