一种改进的Gini系数

A Modified Gini Coefficient

Gini系数是以Lorenz曲线为基础而构造的一个用以衡量收入或财富分配不均等程度的测度指数。在收入分配理论中,Gini系数是一个重要的度量收入分配不平等程度的指标,但由于Gini系数与Lorenz曲线之间不是“一对一”的对应关系,即不同的Lorenz曲线具有相同的Gini系数,从而导致该指标的应用存在着一些缺陷。本文分析了Gini系数不能区分Lorenz曲线的原因,其次通过构造一种加权的Gini系数,对原Gini系数进行了修正,从而解决了原Gini系数无法区分不同的Lorenz曲线的问题。

The Gini coefficient is introduced based on the Lorenz curve. The Gini is an index to measure how fair income or fortune is distributed. In the theory of income distribution, it is an important index to assess the inequality scale of income distribution. But the Gini can not identify the Lorenze curve. Hence the Gini coefficient shows its deficiency in some economic application. In this paper,the relationship between the Gini coefficient and Lorenze curve is discussed and a weighted Gini is created. By correcting the original Gini coefficient, now the updated Gini coefficient can distinguish different Lorenze curves.