Relationship between the weighted distributions and some inequality measures

ABSTRACT

In this paper, we study the relationships between the weighted distributions and the parent distributions in the context of Lorenz curve, Lorenz ordering and inequality measures. These relationships depend on the nature of the weight functions and give rise to interesting connections. The properties of weighted distributions for general weight functions are also investigated. It is shown how to derive and to determine characterizations related to Lorenz curve and other inequality measures for the cases weight functions are increasing or decreasing. Some of the results are applied for special cases of the weighted distributions. We represent the reliability measures of weighted distributions by the inequality measures to obtain some results. Length-biased and equilibrium distributions have been discussed as weighted distributions in the reliability context by concentration curves. We also review and extend the problem of stochastic orderings and aging classes under weighting. Finally, the relationships between the weighted distribution and transformations are discussed.

KEYWORDS:

• Aging classes
• Gini index
• inequality indicators
• lorenz curve
• lorenz order
• weighted distributions

MATHEMATICS SUBJECT CLASSIFICATION:

• 91B15
• 91B80
• 62N05
• 62P20

Acknowledgments

The authors are grateful to the referees for their useful comments and constructive suggestions, which have led to an improved version of the paper.