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| Gabriel Montes-Rojas |
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| ''A note on the variance of average treatment effects estimators'' |
| ( 2009, Vol. 29 No.4 ) |
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| We derive the variance of the Hirano, Imbens and Ridder (Econometrica 66, 315--31, 2003) average treatment effects estimator when the true propensity score is known. This variance is used in the derivation of the variance of a similar two-step estimator, where a M-estimator is used in the first step to estimate the propensity score. |
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| Keywords: Average treatment effects; efficiency bound; two-step estimator; |
JEL: C1 - Econometric and Statistical Methods: General C2 - Single Equation Models; Single Variables: General |
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| Manuscript Received : Sep 04 2009 | | Manuscript Accepted : Nov 24 2009 |
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