Decision Diagrams: Fast and Flexible Support for Case Retrieval and Recommendation
We show how case bases can be compiled into Decision Diagrams, which represent the cases with reduced redundancy. Numerous computations can be performed efficiently on the Decision Diagrams. The ones we illustrate are: counting characteristics of the case base; computing the distance between a user query and all cases in the case base; and retrieving the k best cases from the case base. Through empirical investigation on four case bases, we confirm that Decision Diagrams are more efficient than a conventional algorithm. Finally, we argue that Decision Diagrams are also flexible in that they support a wide range of computations, additional to the retrieval of the k nearest neighbours.
KeywordsCase Base Recommender System Constraint Satisfaction Problem Operation Count Complete Path
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