This paper is devoted to the study of opportunity sets comparisons when the sets may contain options whose characteristics are not completely known. We propose a suitable environment in which this problem can be approached, and provide axiomatic characterizations of several rules for ranking...

This paper is devoted to the study of how to extend a dichotomous partition of a universal set X into good and bad objects to an ordering on the power set of X. We introduce a family of rules that naturally take into account the number of good objects and the number of bad objects, and provide...