Identifying the Unique Polarization Index: A Mean‐Preserving Axiomatic Approach

In this paper, we propose a new axiomatic approach to identify the unique polarization index from a class of polarization measures proposed by Esteban and Ray. Methodologically, we consider the absolute income or the mean normalized income instead of the logarithm of income, which in our opinion is useful under various circumstances. Accordingly, we propose a set of mean‐preserving axioms so that the obfuscating effects of income scale can be removed. We also discuss some properties of the polarization indices based on different types of income differences.