ABSTRACT
A direct determination of WA (cf. Chapter 12) would measure – and average – the inequality ratio ε = β α https://s3-euw1-ap-pe-df-pch-content-public-p.s3.eu-west-1.amazonaws.com/9781315628653/9c36181c-bff3-4e19-a13b-a82ce3632af0/content/pg174_eq143.tif"/> in effect in each exchange in a society – a rather formidable task in data collection and computation. Instead, we estimate WA for a whole society: We approximate WA for any given year with the ratio of the income shares of lower quintiles of a population to the income shares of higher quintiles. Our assumption is that the movement of such ratios would follow that of WA , that is
