Selective Extensions in Game-Tree Search †
Chun Ye, T.A. Marsland · 2013
Although most of today’s chess playing programs still adopt a brute-force approach in their search region, much has been done on search extensions to make the effort spent more worthwhile. In this paper, we discuss some successful search extension heuristics in the domain of Chinese Chess, a game that bears much resemblance to chess. We restrict our experiments to the following: knowledge search extensions, singular extensions, null move search (both in the brute-force and the quiescence search phase) and futility cutoffs. These heuristics have been implemented in Abyss, a Chinese Chess program participating in the 3rd Computer Olympiad. From the algorithmic point of view, since Chinese Chess differs most from chess in its repetition rules, some discussion is also devoted to that matter. 1.