What Works Clearinghouse Standards for Education Impact Evaluations R package baselinr version 0.6.0 Applies the group-design determinations of the What Works Clearinghouse (WWC) to education impact studies. Computes WWC effect sizes (Hedges' g with the small-sample correction, and the Cox index) and classifies baseline equivalence; classifies overall and differential attrition against the WWC attrition boundary; returns the group-design study rating; and reports the robustness of the baseline-equivalence verdict as a multiverse over the computation choices an analyst could defensibly make differently. Provides report-ready tables and Love plots. Software Depends: R (>= 3.5) Imports: rlang, stats Suggests: ggplot2, gt, knitr, rmarkdown, testthat (>= 3.0.0) Yuxia Liang <zl1212@uw.edu> Comprehensive R Archive Network (CRAN) Yuxia Liang [aut, cre] (ORCID: <https://orcid.org/0009-0008-6489-3836>) MIT + file LICENSE (https://CRAN.R-project.org/package=baselinr/LICENSE) 2026-08-22 application/tgz https://CRAN.R-project.org/package=baselinr doi:10.32614/CRAN.package.baselinr en-US