The inequality dataset compiled in the 1990s by the World Bank and extendedby the UN has been both widely used and strongly criticized. The criticisms raisequestions about conclusions drawn from secondary inequality datasets in general. Wedevelop techniques to deal with national and...

Early, the convergence theory was suggestively expressed in the Solow model. This can be shown in line with the fact that while economic development is advancing (expressed by the income per capita growth), on long run there is a general convergence process among countries. Generally, empirical...