n.共分散；协方差
Analysis of covariance is a combination of regression analysis and variance analysis. 协方差分析足把直线回归与方差分析结合起来应用的一种方法。
The data on covariance presently available are here. 目前所能获得的关于协变的资料都在这儿。
The theoretical foundation of the covariance is pertinence of system theory. 协变性的理论基础是系统原理中的相关性。
