Providing convincing explanations to accompany recommendations is a key issue in decision-aiding. In the context of decisions involving multiple criteria, the problem is made very difficult because the decision model itself may involve a complex process. In this paper, we investigate the following issue: when the preferential information provided by the user is incomplete, is there a principled way to define what is a "simple" explanation for a recommended choice? We argue first that explanations may necessitate different levels of detail. Next, we show that even when a detailed explanation is necessary, it is possible to distinguish explanations of different levels of complexity. Our results rely on an original connection we establish between the "mechanics" required to compute supporting coalitions of criteria and the simplicity of the explanation.
展开▼
