| Sumario: | In a recent article in "Review of Economics and Statistics," economist, Hui-Shyong Chang used the form of function suggested by economists George E.P. Box and David R. Cox to estimate the demand for meat in the United States. This article indicates the constraints which this function places upon price and income elasticities, but which may, however, be removed by a slight generalization of the form. According to the author, the simple Box-Cox form imposes unreasonable constraints on the behavior of price and income elasticities. The generalization, in which price and income are raised to individual powers, is not so constrained. Moreover, it is interesting to note that of the four simple functions, introduced earlier as special cases of the generalized Box-Cox function, only the semi-logarithmic fulfills all of these elasticity conditions. This may account for its popularity in empirical work on the demand for food.
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