DRDID package implements different estimators for the average treatment effect on
the treated in difference-in-differences (DID) setups where the parallel trends assumption
holds after you condition on a vector of pre-treatment covariates. The main estimators
implemented here are the locally efficient, doubly-robust DID estimators proposed by
Sant'Anna and Zhao (2020) <https://arxiv.org/abs/1812.01723>. A number of other DID
estimators discussed in Sant'Anna and Zhao (2020) are also implemented.
Sant'Anna, Pedro H. C. and Zhao, Jun. (2020), "Doubly Robust Difference-in-Differences Estimators." Journal of Econometrics, Vol. 219 (1), pp. 101-122, doi:10.1016/j.jeconom.2020.06.003