Indifference and incomparability are different concepts that may lead to different behavioral consequences. Under the assumption that the agent is averse to making a choice between incomparable alternatives, we propose an axiomatic model that allows for a discrimination between indifference and...

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...

This paper contributes to the axiomatization of additive rules for ranking sets of objects under the psychological principle of categorization. Firstly we proceed with the case where the elements in the sets are categorized into at most three groups, namely good (with value 1), neutral (with...