[An efficient estimator for regressions in which the parameter vector can take any of several values is devised. It is shown that although the likelihood function is unbounded, the likelihood equations have a consistent root. An initial consistent estimator is provided. One Newton step provides efficient estimates. Applications to nonlinear models and contaminated normal models are suggested.]

[This paper explores a new approach to the estimation of a joint production technology. Pseudo data, which are obtained by solving a petrochemical process model for alternative relative prices, are used to estimate a price possibility frontier with 3 inputs and 6 outputs. Unlike traditional data sources, pseudo data are not constrained by historical price variation, technologies, and environmental controls. As an econometric exercise, the approximation of the process model's detailed piecewise linear production surface by a single equation "generalized" functional form, the translog, raises a host of interesting empirical and methodological questions.]

[We give an elementary statement and proof of a core equivalence theorem.]

T HEORETICAL work on job search views unemployment as productive search activity. By remaining unemployed, a worker acquires labor market information that helps him/ her maximize lifetime utility. Different models have different predictions with regard to the relation between search time and the resulting wage. For example, under one set of assumptions, the expected resulting wage may increase with increasing search time, while under a different set of assumptions, the relationship may be negative. These two possibilities imply differing relationships of the job searcher to the labor market. In the first case (increasing expected resulting wage), the worker weighs a typical offer against the high probability that a better one will come along later. In the second case (decreasing expected resulting wage), because future offers are likely to be worse than the typical present offer, the worker is more likely than otherwise to take whatever job is available. This paper estimates the relationship between search time and resulting wage. A simultaneous equations framework is used in which search time is endogenous (as well as the resulting wage). It is found that the expected resulting wage declines as search time increases. This result is consistent with the ranking by a searcher of firms according to expected wage offers, with the high wage firms sampled first (Salop, 1973). Further, the determinants of the duration of unemployment are investigated by race-sex groups.

This paper applies a model of the demand for public goods to explain cross-sectional differences in public allocations to agricultural research in the United States. The model postulates that demanders of agricultural research on the state level--primarily farmers and firms producing agricultural inputs--contribute voluntarily to lobbying activity either by voting or by making campaign contributions in order to induce research allocations. A "concentration effect" is derived, in which political participation by the relatively large demanders increases relative to participation by the relatively small demanders, as group size becomes large. The implications of the model are found to be consistent with American data on agricultural research allocations in 1969.