Estimates Two-way Fixed Effects difference-in-differences/event-study models using the approach proposed by Gardner (2021) <doi:10.48550/arXiv.2207.05943>. To avoid the problems caused by OLS estimation of the Two-way Fixed Effects model, this function first estimates the fixed effects and covariates using untreated observations and then in a second stage, estimates the treatment effects.
| Version: | 1.2.0 | 
| Depends: | R (≥ 3.5.0), fixest (≥ 0.13.2) | 
| Imports: | boot, broom, data.table, did, didimputation, dreamerr, ggplot2, HonestDiD, Matrix, rlang, staggered, stats | 
| Suggests: | haven, knitr, rmarkdown, testthat (≥ 3.0.0) | 
| Published: | 2025-09-19 | 
| DOI: | 10.32614/CRAN.package.did2s | 
| Author: | Kyle Butts  [aut,
    cre],
  John Gardner  [aut],
  Grant McDermott  [ctb],
  Laurent Berge [ctb] | 
| Maintainer: | Kyle Butts  <buttskyle96 at gmail.com> | 
| License: | MIT + file LICENSE | 
| URL: | https://kylebutts.github.io/did2s/ | 
| NeedsCompilation: | no | 
| Citation: | did2s citation info | 
| Materials: | README, NEWS | 
| In views: | Econometrics | 
| CRAN checks: | did2s results |