השוואת שיטות

	אומד משתנים מתערבים של אנדרסון-השייאו	שיטת המשתנים המתערבים (IV) להסקה סיבתית	System GMM (Arellano-Bover / Blundell-Bond)
תחום	אקונומטריקה	כלכלת בריאות	אקונומטריקה
משפחה	Regression model	Process / pipeline	Regression model
שנת המקור	1981	1990s (modern applications)	1998
הוגה השיטה	Theodore Anderson & Cheng Hsiao	Angrist & Pischke (applied econometrics); rooted in econometric theory	Arellano & Bover (1995); Blundell & Bond (1998)
סוג	Instrumental variables estimator for dynamic panel data	Method	Dynamic panel data estimator
מקור מכונן	Anderson, T. W., & Hsiao, C. (1981). Estimation of dynamic models with error components. Journal of the American Statistical Association, 76(375), 598–606.	Angrist, J. D., & Pischke, J. S. (2009). Mostly Harmless Econometrics: An Empiricist's Companion. Princeton: Princeton University Press.	Arellano, M. & Bond, S. (1991). Some Tests of Specification for Panel Data: Monte Carlo Evidence and an Application to Employment Equations. Review of Economic Studies, 58(2), 277-297.
כינויים	Anderson-Hsiao Estimator, AH IV Estimator, Dynamic Panel IV Estimator, Anderson-Hsiao Araçsal Değişken Tahmincisi	IV, two-stage least squares, TSLS, causal estimation	Arellano-Bover estimator, Blundell-Bond estimator, dynamic panel GMM, Sistem GMM (Arellano-Bover / Blundell-Bond)
קשורות	2	3	4
תקציר	The Anderson-Hsiao IV estimator is a method for consistently estimating dynamic panel data models that include a lagged dependent variable as a regressor. Proposed by Theodore Anderson and Cheng Hsiao in 1981, it resolves the Nickell bias that arises when fixed effects are eliminated by first-differencing, by instrumenting the differenced lagged dependent variable with its own second lag in levels or differences.	Instrumental variables (IV) is an econometric method to estimate causal effects when treatment or exposure is not randomly assigned and confounding is severe or unmeasured. IV relies on a third variable (instrument) that influences treatment but does not directly affect the outcome, allowing researchers to isolate the causal effect from the noise of confounding. Developed extensively in econometrics (Angrist & Pischke, 1990s–2000s), IV methods are increasingly used in health economics and health services research to leverage natural experiments and policy changes.	System GMM is a generalized method of moments estimator for dynamic panel models that contain a lagged dependent variable. Introduced by Blundell and Bond (1998), building on Arellano and Bover, it augments the differenced equation of the earlier difference GMM (Arellano-Bond) with the equation in levels to deliver consistent estimates when N is large and T is small.