A Theoretical Framework for Tradeoff Generation using Soft Constraints
Tradeoffs have been proposed in the literature as an approach to resolving over-constrainedness in interactive constraint-based tools, such as product configurators, that reason about user preferences . It has been reported how tradeoffs can be modeled as additional constraints. This paper presents a formal framework for tradeoff generation based on the semiring approach to soft constraints. In particular, user preferences and tradeoffs are represented as soft constraints and as an entailment operator, respectively. The entailment operator is used to interactively generate new constraints representing tradeoffs. We also introduce a novel definit ion of substitutability for soft constraints upon which we present a relaxed definition of tradeoffs.
KeywordsUser Preference Constraint Satisfaction Problem Soft Constraint Configuration Process Product Configuration
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