The Normalized Quadratic Expenditure Function

A concise introduction to the Normalized Quadratic expenditure or cost function is provided so that the interested reader will have the necessary information to understand and use this functional form. The Normalized Quadratic is an attractive functional form for use in empirical applications as correct curvature can be imposed in a parsimonious way without losing the desirable property of flexibility. We believe it is unique in this regard. Topics covered included the problem of cardinalizing utility, the modeling of nonhomothetic preferences, the use of spline functions to achieve greater flexibility and the use of a “semiflexible†approach to make it feasible to estimate systems of equations with a large number of commodities.