Building Gorman's Nest

Gorman's class of Engel curve demand models is extended to incomplete demand systems. The Gorman class of aggregable incomplete demand systems admits any transformation of deflated income. A maximum rank of three for the demand equations is a corollary of Slutsky symmetry. Models of incomplete demand systems are developed that nest the rank of the demand system and functional form of the income variables, can be globally restricted to be weakly integrable, can be estimated consistently and efficiently with aggregate market data, and permit inferences on the impacts of policies on consumption and economic welfare for identifiable groups of consumers