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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 <ref>[http://www.open-aurec.com/wbforum/viewtopic.php?f=18&t=42991 When can a game be declared as a draw?] by [[Josué Forte]], [[Computer Chess Forums|Winboard Forum]], June 15, 2003</ref>* 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). * [https://en.wikipedia.org/wiki/Queen_versus_pawn_endgame KQKP] with [https://en.wikipedia.org/wiki/Queen_versus_pawn_endgameQueen versus Pawn#Rook_pawn rook pawn] or [https://en.wikipedia.org/wiki/Queen_versus_pawn_endgame#Bishop_pawn bishop pawn] RookPawn7|Queen versus Rook Pawn on its seventh rank supported by own king threatening [[Stalemate|stalemate]], other king far enough away <ref>[http://www.talkchess.com/forum/viewtopic.php?t=66640 Marcel Duchamp endgame "splits" engines / hash phenomenon] by [[Kenneth W. Regan|Kenneth Regan]], [[CCC7th]], February 19, 2018 » [[Chess Problems, Compositions and Studies]], [[:Category:Marcel DuchampQueen versus Pawn#BishopPawn7|Marcel Duchamp]], [[Transposition TableQueen versus Bishop Pawn on 7th]]</ref> <ref>[http://www.talkchess.com/forum/viewtopic.php?t=66798 what to do when all depths give the exact same score?] by [[Sander Maassen vd Brink]], [[CCC]], March 10, 2018</ref>
* [[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]]* [http://www.open-aurec.com/wbforum/viewtopic.php?f=18&t=42991 When can a game be declared as a draw?] by [[Josué Forte]], [[Computer Chess Forums|Winboard Forum]], June 15, 2003
==2010 ...==
* [http://www.talkchess.com/forum/viewtopic.php?t=34673 question on draw evaluation] by liuzy, [[CCC]], June 03, 2010
* [http://www.talkchess.com/forum/viewtopic.php?t=50223 Discocheck 5.01: Bishop related endgame problems] by [[Michael Scheidl|Mike Scheidl]], [[CCC]], November 25, 2013 » [[DiscoCheck]], [[Color of a Square]], [[Wrong Color Bishop and Rook Pawn]]
==2015 ...==
* [http://www.talkchess.com/forum/viewtopic.php?t=61250 Stockfish eval output] by [[Erin Dame]], [[CCC]], August 27, 2016 » [[Wrong Color Bishop and rook pawnRook Pawn]], [[Stockfish]]
* [http://www.talkchess.com/forum/viewtopic.php?t=62380 draw endgame scaling] by [[Alexandru Mosoi]], [[CCC]], December 04, 2016
* [http://www.talkchess.com/forum/viewtopic.php?t=64115 insufficient mating material] by [[Erin Dame]], [[CCC]], May 29, 2017
* [http://www.talkchess.com/forum/viewtopic.php?t=66798 what to do when all depths give the exact same score?] by [[Sander Maassen vd Brink]], [[CCC]], March 10, 2018
* [http://www.talkchess.com/forum3/viewtopic.php?f=7&t=70827 KQKP and the like] by [[Harm Geert Muller]], [[CCC]], May 25, 2019
* [http://www.talkchess.com/forum3/viewtopic.php?f=7&t=71707 Why does stockfish randomise draw evaluations?] by konsolas[[Vincent Tang]], [[CCC]], September 01, 2019 » [[Stockfish]], [[Score#DrawScore|Draw Score]], [[Search with Random Leaf Values]]==2020 ...==* [http://www.talkchess.com/forum3/viewtopic.php?f=7&t=73012 Endgame woes] by [[Tom King]], [[CCC]], February 07, 2020* [http://www.talkchess.com/forum3/viewtopic.php?f=7&t=74203 OliThink 5.4.0 has been published with an big leap in strength for only 3 lines of code] by [[Oliver Brausch]], [[CCC]], June 16, 2020 » [[OliThink]]* [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]]
=References=
<references />
'''[[Endgame|Up one Level]]'''
[[Category:Marcel Duchamp]]
