The Gini index is a measure of the inequality of a distribution that can be derived from Lorenz curves. While commonly used in, e.g., economic research, it suffers from ambiguity via lack of Lorenz dominance preservation. Here, investigation of large sets of empirical distributions of incomes of the World's countries over several years indicated firstly, that the Gini indices are centered on a ...

Household vehicle ownership is a critical demographic characteristic influencing many aspects of travel demand. Using the 1995 NPTS data set, this research proposes a multivariate negative binomial model to investigate households’ distinctions in vehicle purchases among passenger cars, SUVs, pickups, and minivans. This model structure is capable of capturing unobserved heterogeneity across the ...