Ungrouping Income Distributions - The Italian Doxa Survey of 1948

Abstract: This paper investigates alternative statistical approaches to ungroup data in tabular form. After a theoretical discussion on the interpolation problem and on the features of ungrouping techniques, a non-parametric version of the algorithm of Shorrocks and Wan is introduced. The effectiveness of the different methods is assessed using recent microdata on Italian incomes available in the Bank of Italy's Survey on Households Income and Wealth. Taking advantage of this evaluation, the most suitable ungrouping methods are applied to the Doxa Survey of 1948, the first research on Italian households' incomes based on a probability sampling procedure. Lastly, the reconstructed samples of historical microdata are used to compute inequality and poverty measures