Income Distribution at Flint: A Comparison of the Inequality with Other American Cities.

The topic of this presentation is the study of the income distributions of Flint for four decades from the 1980 to the 2010. The distributions are compared with the ones of other American cities in order to analyse their different stories of the lasts forty years. In particular we are interested to the inequality observed in such distributions and it has to be observed together with the average value. First of all is presented a descriptive analysis, where the Gini index [Gini, 1914] and the Zenga index I [Zenga, 2007] of the sample distributions are showed. Observe that such indexes may be influenced by the mean value of the distribution. Therefore, data are fitted with a new model distribution. This model is proposed by Zenga [2010] to describe income distributions and it origins from the inequality index I. The model depends on three parameters. One of them is a scale parameter and it corresponds to the expectation. The inequality does not change in case of scale transformations, therefore the model expectation does not affect the shape of the distribution and the inequality measures. For each fitted model the Gini index and the Zenga index I are provided. Moreover, it is presented how the shape parameters influence the inequality, and more informations about the income distributions are obtained by the comparison of the estimated values of such parameters.