On a Method of Computing Engel Elasticities from Concentration Curves
从集中曲线计算恩格尔弹性的方法
THIS PAPER PRESENTS, on the assumption of lognormality, a simple graphical method of deriving the Engel elasticities for various items of consumer expenditure from what are known as concentration curves. Usually two types of such curves are distinguished: (a) the Lorenz curve which relates the proportion of total expenditure to the proportion of persons spending up to a given level of total expenditure per capita, and (b) the specific concentration curve which relates the…