The Yule-Frisch-Waugh-Lovell Theorem for Linear Instrumental Variables Estimation
线性工具变量估计中的 Yule–Frisch–Waugh–Lovell 定理
In this paper, I discuss three aspects of the Frisch-Waugh-Lovell theorem. First, I show that the theorem holds for linear instrumental variables estimation of a multiple regression model that is either exactly or overidentified. I show that with linear instrumental variables estimation: (a) coefficients on endogenous variables are identical in full and partial (or residualized) regressions; (b) residual vectors are identical for full and partial regressions; and (c)…