Alpha-Beta Search Revisited
An algorithm, Aspiration Scout/MTD(f), is derived from an analysis of alpha-beta (α-β) tree search. When compared to its predecessors, it results in an average 10.1% reduction in search effort with a best case of 17.4%. 1 The search space is usually referred to as a tree, however in games such as chess and draughts it is actually a directed acyclic graph (DAG). Programs search a dynamically unfolding DAG.
KeywordsLeaf Node Directed Acyclic Graph Search Effort Node Count Interior Node
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