Computes the QDiD ATT and counterfactual outcome distribution
for a single 2x2 (pre/post x treated/control) data subset. Serves
directly as the attgt_fun argument to ptetools::pte. Panel
vs. repeated cross sections is detected automatically from whether the
same unit ids appear in both periods.
Arguments
- gt_data
A data frame (typically a
gt_data_framefromptetools) with columnsname("pre"or"post"),D(treatment dummy),Y(outcome),id(unit identifier),.w(sampling weights), and any covariate columns referenced byxformula.- xformula
One-sided formula for covariates. Default
~1uses no covariates. With covariates, conditional quantile regressions are used following Athey and Imbens (2006).- ...
Additional arguments passed through by
ptetools; not used directly.
Value
A ptetools::attgt_noif object with the ATT estimate and, in
extra_gt_returns, three objects: F1 (weighted ECDF of
observed treated outcomes in the post period), F0 (weighted ECDF
of counterfactual untreated outcomes for the treated group), and Fte
(weighted ECDF of individual treatment effects; NULL for repeated
cross sections).