Empirical studies of consumer demand or of factor demand have now moved far beyond the Cobb-Douglas functional form and elasticities of interest are no longer estimated as parameters of the system. Instead, such elasticities are typically non-linear functions of the parameters that have been estimated and it is natural to want to be able to say something about the statistical properties of such elasticities. One way of dealing with this is to linearly approximate the elasticity formulas (in terms of the estimated parameters) and use classical statistical procedures to get approximations to the underlying variances. If y-f(x) and x has a variance covariance matrix V, the linear approximation is given by: Var(y) (8f/8x)V(8f/8x). The data needed for such an approximation are estimates of the parameters and of the associated variance-covariance matrix. Some of the earliest references that we have found to uses of this approximation technique in the elasticity context are to Griffin and Gregory (1976), Griffin (1977), and Fuss (1977), while the earliest references to

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Using micro data from the Canadian Survey of Consumer Finances, 1971-91, we investigate the return to a university education. Our conclusions are that while there appears to have been some decline in the return to a university degree during the 1970s in Canada (similar to the United States), the return did not rebound much during the 1980s except among the youngest experience (age) group. There is, however, considerable noise in the ratios from year to year so that one is likely to draw misleading inferences if only a few years of data are used.