The Gini index is the most commonly used measure of income inequality. Like any single summary measure of a set of data it cannot capture all aspects that are of interest to researchers. One of its widely reported flaws is that it is supposed to be overly sensitive to changes in the middle of...

The increase in income inequality in many countries, apparently due to a greater relative increase in upper incomes, has become a public policy concern. This paper shows that the standard Gini index underestimates the rate of increase in inequality because a shift of income towards the top...