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a selective search enhancement of the [[Alpha-Beta|alpha-beta]] algorithm created in 1994 by [[Michael Buro]] as introduced in his Ph.D. thesis <ref>[[Michael Buro]] ('''1994'''). ''Techniken für die Bewertung von Spielsituationen anhand von Beispielen.'' Ph.D. Thesis. [[Paderborn University]], Paderborn, Germany. (German), Kapitel 4. Selektive Suche</ref>. It permits to exclude probably irrelevant subtrees from beeing searched deeply. ProbCut and its improved variant '''Multi–ProbCut''' (MPC) have been shown to be effective in [[Othello]] <ref>[[Michael Buro]] ('''1997'''). ''Experiments with Multi-ProbCut and a New High-quality Evaluation Function for Othello.'' Technical Report No. 96, NEC Research Institute, Princeton, N.J. [https://skatgame.net/mburo/ps/improve.pdf pdf]</ref> and [[Shogi]] <ref>[[Kazutomo Shibahara]], [[Nobuo Inui]], [[Yoshiyuki Kotani]] ('''2002'''). ''Effect of ProbCut in Shogi - by changing parameters according to position category''. [[Conferences#GPW|7th Game Programming Workshop]]</ref>, and a technique similar to ProbCut is used in the [[Checkers|checkers]] program [[Chinook]] by [[Jonathan Schaeffer|Schaeffer]] et al. (1992) <ref>[[Jonathan Schaeffer]], [[Joe Culberson]], [[Norman Treloar]], [[Brent Knight]], [[Paul Lu]], [[Duane Szafron]] ('''1992'''). ''A World Championship Caliber Checkers Program''. [https://en.wikipedia.org/wiki/Artificial_Intelligence_%28journal%29 Artificial Intelligence], Vol. 53, Nos. 2-3, pp. 6, "If a line leads to a material deficit and there is insufficient positional compensation (the positional assessment of the position does not reach a fixed threshold) then the remaining search depth is cut in half. If the result of this search does not restore the material deficit, or result in sufficient positional compensation, this line is abandoned. Otherwise, the line is researched to the full search depth".</ref> described their approach in a footnodefootnote: Chinook performs forward cuts in positions with a [[Material|material]] deficit, where a shallow search does not show an escape. ProbCut is a generalization of this method in that it is game independent. It was tested by incorporating it in Buro's already strong Othello program ''Logistello'' <ref>[http://skatgame.net/mburo/log.html LOGISTELLO's Homepage]</ref> and increased the program's playing strength <ref>[[Michael Buro]] ('''1995'''). ''ProbCut: An Effective Selective Extension of the Alpha-Beta Algorithm.'' [[ICGA Journal#18_2|ICCA Journal, Vol 18, No. 2]], [https://skatgame.net/mburo/ps/probcut.pdf pdf]