Inventory Models

Econometric aspects of recent research on inventory models are surveyed. The discussion emphasizes issues relevant to instrumental variables estimation of a first order condition of the Holt et al. (1960) linear quadratic inventory model, including choice of instruments, covariance matrix estimation, methods for testing, and implications of unit root nonstationarity. The paper also briefly discusses estimation of a decision rule implied by the model, and, finally, the impliations for inventory models of some stylized facts about inventories.