Inequality in the very long run: inferring inequality from data on social groups.

This is a post-peer-review, pre-copyedit version of an article published in The Journal of Economic Inequality. The final authenticated version is available online at https://doi.org/10.1007/s10888-014-9279-6This paper presents a new method for calculating Gini coefficients from tabulations of the mean income of social classes. Income distribution data from before the Industrial Revolution usually come in the form of such tabulations, called social tables. Inequality indices generated from social tables are frequently calculated without adjusting for within-group income dispersion, leading to a systematic downward bias in the reporting of pre-industrial inequality. The correction method presented in this paper is applied to an existing collection of twenty-five social tables, from Rome in AD 1 to India in 1947. The corrections, using a variety of assumptions on within-group dispersion, lead to substantial increases in the Gini coefficients.This paper is part of the research activities at the centre of Equality, Social Organization, and Performance (ESOP) at the Department of Economics at the University of Oslo. ESOP is supported by the Research Council of Norway.acceptedVersio