Estimating Models of Supply and Demand: Instruments and Covariance Restrictions
研究了在不完全竞争下估计供给与需求模型的方法，提出利用未观测需求与成本冲击之间的协方差约束来解决内生性并识别价格参数，并与工具变量法进行比较，通过谷物、水泥和航空业的应用案例展示该方法。
We consider the identification of empirical models of supply and demand with imperfect competition. We show that a restriction on the covariance between unobserved demand and cost shocks can resolve endogeneity and identify the price parameter. We demonstrate how to employ this approach in estimation, and we compare it to the method of instrumental variables. Our formal results also indicate that weaker covariance restrictions can bound the price parameter. We illustrate the covariance restriction approach with applications to ready-to-eat cereal, cement, and airlines.