Most econometric multi-equation models estimated are assumed to be linear in both the variables and the parameters. One reason is that, in general, methods of linear algebra cannot be applied to nonlinear systems. <p> In this paper a certain class of nonlinear models is defined, however, the...</p>

A regression model is considered where earnings are explained by schooling and ability. It is assumed that schooling is measured with error and that there are no data on ability. Regressing earnings on observed schooling then yields an estimate of the return to schooling that is subject to...

Productivity measurement is considered in the context of incomplete output information. Only a value measure of output is assumed to be available, which is typical for many service industries. Input markets are assumed to be competitive, while the output market is allowed to be noncompetitive,...

Investigating the robustness of the skill-biased technical change hypothesis, this analysis incorporates two novel features. First, effective labor is modeled as the product of a quantity measure - number of employees with a given level of education - and a quality index. The quality index,...