Population and Sample Selection Effects in Measuring International Income Inequality

In: Journal of world-systems research, S. 8-28

Abstract

The issue of world income inequality has been debated widely in the literature. At issue is whether inequality has, on the whole, been increasing or decreasing over time. I reexamine results from Firebaugh's (1999) seminal article on demographic e?ects on inequality, in which he found a 30-year "plateau" of world income inequality when countries are weighted based on their populations. In contrast, I show that the increasing integration of market economies over the past decades has been re?ected in dramatically increasing international inequality. "Inequality" as currently measured, however, may bear little resemblance to a naive under-standing of the term. I conclude with some preliminary ?gures from an alternate characterization of convergence and divergence, based on world-systems categories.