A generalised quiescence search algorithm

摘要

This paper describes how the concept of a null move may be used to define a generalised quiescence search applicable to any minimax problem. Experimental results in the domain of chess tactics show major gains in cost effectiveness over full-width searches, and it is suggested that null-move quiescence may be almost as widely useful as the alpha-beta mechanism. The essence of the mechanism is that null moves give rise to bounds on position values which are more reliable than evaluations. When opposing bounds touch, they create a single value which is more reliable than ordinary evaluations, and the search is terminated at that point. These terminations are prior to any alpha-beta cutoffs, and can lead to self-terminating searches.