Ethical Indices of Income Mobility

Abstract

Indices of inequality are typically summary statistics of the dispersion of incomes at a particular point of time. Even if such indices are computed for a number of successive periods, by their very nature they will ignore many features of time path of incomes which are of interest. As time progresses we observe changes in relative incomes as well as changes in the absolute income differences found in any given time period. Indices of income mobility are meant to measure the magnitude of these changes. Indices of relative mobility measure changes in relative incomes while indices of absolute mobility measure changes in income differences.