A Class of Unbiased Estimators of the Average Treatment Effect in Randomized Experiments

  title={A Class of Unbiased Estimators of the Average Treatment Effect in Randomized Experiments},
  author={Peter M. Aronow and Joel A. Middleton},
Abstract We derive a class of design-based estimators for the average treatment effect that are unbiased whenever the treatment assignment process is known. We generalize these estimators to include unbiased covariate adjustment using any model for outcomes that the analyst chooses. We then provide expressions and conservative estimators for the variance of the proposed estimators. 

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