A Class of Practical and Acceptable Social Welfare Orderings That Satisfy the Principles of Aggregation and Non-Aggregation : Reexamination of the Tyrannies of Aggregation and Non-Aggregation

This paper revisits impossibility results on the tyrannies of aggregation and non-aggregation. I propose two aggregation principles --quantitative aggregation and ratio aggregation—and investigate theoretical implications. As a result, I show that quantitative aggregation and minimal non-aggregation are incompatible while ratio aggregation and minimal non-aggregation are compatible under the assumption of standard axioms in social choice theory. Furthermore, this study provides a new characterization of the leximin rule by using replication invariance and the strong version of non-aggregation. Finally, I propose a class of practical and acceptable social welfare orderings that satisfy the principles of aggregation and non-aggregation, which has various advantages over the standard rank-discounted generalized utilitarianism.