השוואת שיטות

	ריבועים פחותים משוקללים לא-לינאריים (NWLS)	שיטת הריבועים הפחותים המוכללת (GLS)
תחום	אקונומטריקה	סטטיסטיקה
משפחה	Regression model	Regression model
שנת המקור	1960s–1980s (formalized in applied econometrics)	1935
הוגה השיטה	Extension of Gauss-Newton nonlinear least squares with Aitken-type weighting	Alexander Craig Aitken
סוג	Nonlinear regression estimator	Linear estimator
מקור מכונן	Greene, W. H. (2018). Econometric Analysis (8th ed.). Pearson Education. ISBN: 978-0134461366	Aitken, A. C. (1935). IV.—On least squares and linear combination of observations. Proceedings of the Royal Society of Edinburgh, 55, 42–48.
כינויים	NWLS, nonlinear weighted least squares, weighted nonlinear regression, heteroscedasticity-corrected nonlinear regression	GLS, Aitken estimator, EGLS, feasible GLS
קשורות	3	3
תקציר	Nonlinear Weighted Least Squares combines the flexibility of nonlinear regression with the variance-stabilizing power of observation-level weights. It minimises a weighted sum of squared residuals around a user-specified nonlinear mean function, making it the method of choice when the relationship is inherently nonlinear and error variance differs across observations.	Generalized Least Squares (GLS) is a linear regression estimator that extends ordinary least squares to handle situations where the error terms are correlated or have non-constant variance (heteroscedasticity). Introduced by Alexander Craig Aitken in 1935, GLS achieves the Best Linear Unbiased Estimator (BLUE) under a general error covariance structure by weighting observations according to their precision, providing a theoretical bridge between OLS and modern linear mixed models.