Mathematical models which relate the growth rate of a microorganism to a single limiting substrate concentration have long been established. In recent years, it has become apparent that, under certain conditions, the growth rate of an organism may be simultaneously limited by two or more...

The identification and estimation of a semiparametric simultaneous equation model with selectivity have been considered. The identification of structural parameters from reduced form parameters in the semiparametric model requires stronger conditions than the usual rank condition in the...

Luce's Biased Choice Model has never had a serious competitor as a model of identification data. Even when it has provided a poor model of such data, other models have done even less well. Two alternative models are presented and the three are fit to a published data set. One alternative model...

In this paper, we define dynamic and static factors and distinguish between the dynamic and static structure of asset excess returns. We examine the value-weighted market portfolio as a dynamic factor and propose an intuitively appealing procedure to search for more dynamic factors. We find...