A parametric specification of an indirect utility function in terms of expenditure and two unit cost functions.is.proposed.Specification of these unit cost functions in terms of regular functions leads to the notion of an "effectively globally regular" system of demand equations; that is, a system of demand equations that is regular over a cone in expenditure-price space, and for which the regular region includes all points in any given sample, and all values of nominal expenditure and prices generating higher values of real expenditure than the sample minimum.This general model nests a number of popular demand systems, such as the Linear Expenditure System, as special cases.An empirical application demonstrates the value of the generalization.

ONE of the most puzzling dichotomies in economics is that between the microeconomic theory of consumer demand and the consumption function of macroeconomics. Although there is now a highly developed literature on the specification and estimation of systems of consumer demand equations, this is basically a theory of allocation, i.e., given the level of consumption, how is it to be allocated among the various categories of consumer goods? This literature takes as given the allocation of current income between consumption and savings, and hence contributes very little to the specification of the consumption function. A notable exception to this dichotomy is the Extended Linear Expenditure System (ELES) proposed by Lluch (1973), an intertemporal model of consumer decision making which endogenizes not only the allocation of consumption across commodities, but also the consumption-saving decision, and hence generates a consumption function which is firmly based in microeconomic theory. However, ELES is based on the rather special Klein-Rubin instantaneous utility function, which will be shown below to have quite restrictive implications. In fact, when the problem is set up in terms of the indirect utility function, generalizations of the Klein-Rubin form are easily incorporated into the intertemporal optimization problem. A second generalization of ELES relates to price expectations. Most empirical applications of ELES, for example, Lluch, Powell and Williams (1977), Lluch and Williams (1975) and Powell (1973) have generally assumed static price expectations and have depended upon the continual replanning assumption to justify observed price movement through time. Where price expectations have been considered, it has usually been in an ad hoc manner. Additionally, these models have generally assumed constant (current) nominal interest rate expectations,'which would appear to be inconsistent with an assumption of stationary price expectations, since the current nominal rate of interest will include a premium for inflation. In a previous paper (Cooper and McLaren (1980a)), an initial attempt was made to integrate a model of the formation of price expectations into an intertemporal consumer decision making model at the optimization stage. Two weaknesses of this model were the restriction to the case of a Klein-Rubin utility function, and the inconsistency of the assumptions made about interest rate expectations with those on price expectations. In the following two sections we present a reasonably general model of intertemporal consumer decision making incorporating price and interest rate expectations which overcomes these two weaknesses. Section IV presents the estimating forms based on a particular choice of functional forms, and estimates using Australian data are presented in section V.