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=Obvious Draws=
According to the rules of a dead position, Article 5.2 b, when there is no possibility of [[Checkmate|checkmate]] for either side with any series of legal moves, the position is an immediate draw if
* both sides Both Sides have a bare king King * one side One Side has a king King and a minor piece Minor Piece against a bare king King * both sides Both Sides have a king King and a bishopBishop, the bishops Bishops being the same colorColor
=Simple Heuristics=
The bishops of different colors are not counted as an immediate draw, because of the possibility of a helpmate in the corner. Since this is unlikely given even a four ply search, we may introduce another class of drawn positions: those that cannot be claimed, but can be evaluated as draws:
* two knights Two Knights against the bare kingKing* both sides Both Sides have a king King and a minor piece Minor Piece each * the weaker side The Weaker Side has a minor piece Minor Piece against two knights Knights * two bishops Two Bishops draw against a bishop Bishop * two minor pieces Two Minor Pieces against one draw, except when the stronger side Stronger Side has a [[Bishop Pair|bishop pair]]
Please note that a knight or even two knights against two bishops are not included here, as it is possible to win this ending.
=Complex Heuristics=
* If the stronger side Stronger Side has a pawn Pawn and a bishop Bishop against the minor pieceMinor Piece, the position Position is almost certainly drawn if the weaker sideWeaker Side's king King occupies a square Square on the path Path of a pawn Pawn that is inaccessible to the enemy bishop Bishop (the The degenerate cases like trapping Trapping the minor piece Minor Piece are best left for searchSearch).
* [[Queen versus Pawn#RookPawn7|Queen versus Rook Pawn on 7th]] and [[Queen versus Pawn#BishopPawn7|Queen versus Bishop Pawn on 7th]]
* [[Wrong Color Bishop and Rook Pawn]]
=One-sided Heuristics=
There are some heuristics that tells us only that one of the players cannot win the endgame
* a A single minor piece Minor Piece should not win against any number of pawns Pawns (again, there is a special case of a smothered mate in the corner, but it is search Search issue, not to be taken into account by the [[Evaluation Function|evaluation function]])
=See also=
==2000 ...==
* [https://www.stmintz.com/ccc/index.php?id=182927 "Don't trust draw score" <=Is it true?] by [[Teerapong Tovirat]], [[CCC]], August 08, 2001 » [[Repetitions]], [[Transposition Table]], [[Path-Dependency]]
* [https://www.stmintz.com/ccc/index.php?id=193257 Draw recognition by eval problems] by [[Rafael B. Andrist]], [[CCC]], October 17, 2001 » [[Wrong Color Bishop and Rook Pawn]]
==2010 ...==
* [http://www.talkchess.com/forum/viewtopic.php?t=34673 question on draw evaluation] by liuzy, [[CCC]], June 03, 2010
* [http://www.talkchess.com/forum3/viewtopic.php?f=7&t=77497 Alpha-beta search for drawing endgames] by Emanuel Torres, [[CCC]], June 16, 2021 » [[Alpha-Beta]], [[Graph History Interaction]], [[Repetitions]]
'''[[Endgame|Up one Level]]'''
[[Category:Marcel Duchamp]]
