방법 비교

	강건 OLS (강건 표준 오차를 사용한 OLS)	가중 최소 제곱법 (Weighted Least Squares, WLS)
분야	계량경제학	통계학
계열	Regression model	Regression model
기원 연도	1980	1935
창시자	Halbert White	Alexander Craig Aitken
유형	Linear regression with robust inference	Weighted linear estimator
원전	White, H. (1980). A heteroskedasticity-consistent covariance matrix estimator and a direct test for heteroskedasticity. Econometrica, 48(4), 817–838.	Aitken, A. C. (1935). IV.—On least squares and linear combination of observations. Proceedings of the Royal Society of Edinburgh, 55, 42–48.
별칭	HC robust regression, White robust OLS, sandwich estimator OLS, OLS with robust standard errors	WLS, weighted regression, heteroscedasticity-corrected OLS, variance-weighted least squares
관련	6	3
요약	Robust OLS applies ordinary least squares to estimate coefficients and then replaces the classical standard errors with heteroscedasticity-consistent (HC) standard errors — commonly called White standard errors. This leaves the point estimates unchanged while yielding valid t-statistics and confidence intervals even when the error variance is not constant across observations.	Weighted Least Squares is a generalization of Ordinary Least Squares (OLS) regression that assigns each observation a weight inversely proportional to its error variance, thereby down-weighting high-variance data points and up-weighting precise ones. Introduced in its general matrix form by Alexander Craig Aitken in 1935, WLS is the canonical remedy when heteroscedasticity is present and the error variance structure is known or can be reliably estimated.