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Home * Chess * Draw

Elke Rehder - Remis (1990) [1]

the outcome of a chess game when it appears that neither side will win. Draws are codified by various rules of chess including stalemate, threefold repetition, and the fifty-move rule. A draw also occurs when neither player has sufficient material to checkmate the opponent or when no sequence of legal moves can lead to checkmate.

Players may further agree to a draw, the side to move may not only claim, but offer a draw, the other side may accept or decline - in computer chess, conform to a protocol and considering game stage, late endgame material configuration, score history and forecast. In official over the board computer chess tournaments such as the World Computer Chess Championship, operator draw agreements require confirmation by the tournament director or arbiter.

Recognizing Draws

The primary purpose to recognize draws is to direct the chess program to produce drawing moves if alternatives are likely losing, or to avoid draws if ahead and alternative moves most likely win as reflected by the score of the minimax search.

Draw Score

Usually, assuming symmetric evaluation and negamaxed values, positive scores indicate the side to move is ahead, and negative if behind, which defines the value of zero as a natural draw score. However, a score of zero does not necessarily reflect a draw score, but a score of a equal or balanced position. Same is true, if programs apply a contempt factor considering the relative strength of the opponent.

Cray Blitz

Cray Blitz applied a special draw heuristic, not uniformly using zero as draw score, but rather zero plus the ply distance to the root to prefer later draws rather than a draw now. Additionally, the draw score range is disjoint from evaluation scores, which then exclude values around zero by adding or subtracting appropriate offsets if either greater or equal, or less than zero [2].

Draw Topics

See also


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External Links

Grandmaster draw from Wikipedia


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