Showing papers by "Terence Wales published in 1987"

Flexible Functional Forms and Global Curvature Conditions

Abstract: Empirically estimated flexible functional forms frequently fail to satisfy the appropriate theoretical curvature conditions. Lau and Gallant and Golub have worked out methods for imposing the appropriate curvature conditions locally, but those local techniques frequently fail to yield satisfactory results. We develop two methods for imposing curvature conditions globally in the context of cost function estimation. The first method adopts Lau's technique to a generalization of a functional form first proposed by McFadden. Using this Generalized McFadden functional form, it turns out that imposing the appropriate curvature conditions at one data point imposes the conditions globally. The second method adopts a technique used by McFadden and Barnett, which is based on the fact that a non-negative sum of concave functions will be concave. Our various suggested techniques are illustrated using the U.S. Manufacturing data utilized by Berndt and Khaled

Specification and Estimation of Nonseparable Two-Stage Technologies: The Leontief CES and the Cobb-Douglas CES

Abstract: A two-stage technology is a sequential production process that first uses pri mary inputs to produce intermediate inputs and then uses theintermediate inputs to produce final output. In this paper the authors show that two-stage technologies provide a general procedure for combining production functions or cost functions to obtain new specifications suitable for empirical production analysis. They investigate two new cost functions for which the input demand systemssatisfy global regularity conditions in a wide range of nondegenerate cases. Using six data sets, the authors estimate thesetwo input demand systems, both with and without imposing global regularity conditions, and find that one of them performs well. Copyright 1987 by University of Chicago Press.

Pooling International Consumption Data

Abstract: Pooling consumption data from different countries for demand system estimation is attractive because it increases both sample size and therange of v ariation of relative prices and income. The major objection to pooling is that d ifferent countries may have different demand system parameters. This paper propo sed and estimates specifications that permit pooling while allowing both short-r un andlong-run demand systems to differ across countries. Using data from Belgi um, the United Kingdom, and the United States, the authors findthat, although p ooling was accepted for some pairs of countries and some specifications, it was rejected for most. They conclude that caution is appropriate in pooling internat ional consumption data. Copyright 1987 by MIT Press.