Abstract
This paper addresses two issues: how to choose between solutions for a problem specified by multiple criteria, and how to search for solutions in such situations. We argue against an approach common in decision theory, reducing several criteria to a single ‘cost’ (e.g., using a weighted sum cost function) and instead propose a way of partially ordering solutions satisfying a set of prioritised soft constraints. We describe a generalisation of the A* search algorithm which uses this ordering and prove that under certain reasonable assumptions the algorithm is complete and optimal.
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Alechina, N., Logan, B. State Space Search with Prioritised Soft Constraints. Applied Intelligence 14, 263–272 (2001). https://doi.org/10.1023/A:1011242703014
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DOI: https://doi.org/10.1023/A:1011242703014