Lexicographic social ranking
摘要
In this paper we focus on the analysis of ranking methods based on a lexicographic comparison of individual evaluations. Notable examples of ranking methods in this family are the majority judgement, the lexicographic excellence and its dual version. Making a bridge with the theory of lexicographic preferences on elements with multiple factors, we provide an axiomatic characterization of the family of lexicographic methods using three well-studied properties in social choice: Anonymity, Neutrality and Independence of Irrelevant Alternatives. These assumptions allow restricting the study to the set of individual evaluations rearranged in a non increasing way. Two further assumptions of Ordinal Invariance and Dominance (restricted to this domain) allow for the requested characterization. Some operational indications on how to establish the order used by the lexicographic procedure is also discussed.