NEWS

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DRDID 1.2.1

• Fix typo on returning influence functions for TWFE regressions.

DRDID 1.2.0 (2024-10-07)

• Improve code to avoid redundant data checks

  • Use fastglm instead of parglm for improved speed

DRDID 1.1.0 (2024-09-05)

• Restore solve as default to invert matrix, as it is faster than qr.solve for small matrices.

  • Improve error handling for non-invertible matrices.

  • Changing estimation methods for fastglm and parglm (in place of lm and glm).

  • Do not let the estimated propensity score be above 1 - 1e-6 (instead of 1 - e-16).

DRDID 1.0.7 (2024-07-05)

• Speed up data processing using Rcpp

  • The weights are now enforced to be normalized and have mean 1 across all observations.

DRDID 1.0.6 (2023-05-18)

• Use qr.solve as default (instead of solve)

  • Drop collinear variables in pre_process_drdid.R (useful in drdid command but not other commands)

  • Add compatibility with R 3.5

  • Improve invertibility of outcome regression design matrix

DRDID 1.0.4 (2022-07-19)

• Fixed links

DRDID 1.0.3 (2021-11-13)

• Add new flags for non-unique unit identifier

  • Better handle of factor variables as covariates

DRDID 1.0.2

• Fix issue with NA in covariates

DRDID 1.0.1 (2021-01-07)

• Allows for treating covariates as factor and alike when computing DiD

  • Improve error and warning handling due to collinearity and convergence issues.

DRDID 1.0.0 (2020-05-18)

• First official version of package, functions for computing a variety of difference-in-differences (DiD) estimators for the ATT.

  • Documentation is improved compared to the devel version, including examples for every function now.

  • Created wrapper function drdid, ordid and ipwdid to implement doubly-robust, outcome regression and inverse probability weighted DID estimators.

  • Add dataset used in the empirical application of Sant'Anna and Zhao (2020).