A re‐interpretation of the linear quadratic model when inventories and sales are polynomially cointegrated
针对美国近二十年数据中库存与销售的非平稳特性，提出使用多项式协整的线性二次模型，该模型在聚合与细分数据上表现良好，为库存研究提供了更贴合实际的方法。
Abstract Estimation of the linear quadratic model, the workhorse of the inventory literature, traditionally takes inventories and sales to be first‐difference stationary series, and the ratio of the two variables to be stationary. However, these assumptions do not always match the properties of the data for the last two decades in the United States. We propose a model that allows for the non‐stationary characteristics of the data, using polynomial cointegration. We show that the closed‐form solution has other recent models as special cases. The resulting model performs well on aggregate and disaggregated data. Copyright © 2006 John Wiley & Sons, Ltd.