In this paper we introduce a new two-factor commodity term structure model for which inventories serve as a second state variable. We derive a closed-form formula for futures prices and empirically analyze the model's properties. Besides being economically appealing, our model also outperforms...

An implication of the von Liebig hypothesis is that crop-production functions have right-angle isoquants. This article presents a nonparametric estimation of right-angle isoquant production functions. It then describes a new test for right-angle isoquants. The procedures are used to test...