Nogood Learning for Constraint Satisfaction
نویسندگان
چکیده
The basic algorithm is derived from the weak-commitment algorithm (WC) of Yokoo [17], which has been shown to outperform breakout and min-conflict backtracking on certain classes of problems. Weakcommitment search is that part of WC which results from removing the learning mechanism; this will be called WC-NL. WC-NL is coupled with learning-by-merging to form the new algorithm WC-NG. Experiments on a range of problems yield two indicative results: (i) WC-NL and WC-NG always outperform WC, and (ii) for harder problems WC-NG always outperforms WC-NL. It should be noted that for easier problems learning-by-merging never significantly degrades the performance of WC-NL.
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