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Enhanced Realization Probability Search

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    (MICC-IKAT Games and AI Group, Faculty of Humanities and Sciences, Universiteit Maastricht, P.O. Box 616 6200MD Maastricht, The Netherlands)



    (School of Computer Science, Reykjavík University, Ofanleiti 2 IS-103 Reykjavík, Iceland)

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    In this paper, we show that Realization Probability Search (RPS) significantly improves the playing strength of a world-class Lines-of-Action (LOA) computer program, even when used in combination with existing state-of-the-art αβ search enhancements. In a 600-game match, a RPS-based version of the program defeats the original one with a winning score of 62.5%. The main contribution of the paper, however, is the introduction of a much improved variant of RPS, called Enhanced Realization Probability Search (ERPS). The new algorithm addresses two weaknesses of RPS and overcomes them by using a better focussed re-searching scheme, resulting in both more robust tactical play and reduced search overhead. Our experiments in the domain of LOA show that ERPS offers just as a significant improvement over regular RPS, as the latter improves upon regular search. More specifically, the ERPS-based variant scores 62.1% against the RPS variant, and an impressive 72.2% score against the original program. This represents an improvement of over 100 ELO points over the original state-of-the-art player.

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    Article provided by World Scientific Publishing Co. Pte. Ltd. in its journal New Mathematics and Natural Computation.

    Volume (Year): 04 (2008)
    Issue (Month): 03 ()
    Pages: 329-342

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    Handle: RePEc:wsi:nmncxx:v:04:y:2008:i:03:p:329-342
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