AE98                    Random subsample from the data of Angrist &
                        Evans (1991).
crosspred               Cross-Predictions using Stacking.
crossval                Estimator of the Mean Squared Prediction Error
                        using Cross-Validation.
ddml_ate                Estimators of Average Treatment Effects.
ddml_fpliv              Estimator for the Flexible Partially Linear IV
                        Model.
ddml_late               Estimator of the Local Average Treatment
                        Effect.
ddml_pliv               Estimator for the Partially Linear IV Model.
ddml_plm                Estimator for the Partially Linear Model.
mdl_glm                 Wrapper for 'stats::glm()'.
mdl_glmnet              Wrapper for 'glmnet::glmnet()'.
mdl_ranger              Wrapper for 'ranger::ranger()'.
mdl_xgboost             Wrapper for 'xgboost::xgboost()'.
ols                     Ordinary least squares.
print.summary.ddml_ate
                        Print Methods for Treatment Effect Estimators.
print.summary.ddml_fpliv
                        Print Methods for Treatment Effect Estimators.
shortstacking           Predictions using Short-Stacking.
summary.ddml_ate        Inference Methods for Treatment Effect
                        Estimators.
summary.ddml_fpliv      Inference Methods for Partially Linear
                        Estimators.
