The Rank of Demand Systems: Theory and Nonparametric Estimation
扩展了Gorman的恩格尔曲线概念至任意需求系统，证明秩对需求的可分性和加总有影响，并基于英美消费者调查数据提出一种非参数秩检验方法，用于评估代表性消费者模型中的加总误差。
W. M. Gorman's (1981) concept of Engel curve is extended to apply to any demand system. Rank is shown to have implications for specification, separability, and aggregation of demands. A simple nonparametric test of rank using Engel curve data is described and applied to U.S. and U.K. consumer survey data. The test employs a new general method for testing the rank of estimated matrices. The results are used to assess theoretical and empirical aggregation error in representative consumer models, and to explain a representative consumer paradox. Copyright 1991 by The Econometric Society.