Data Analysis with Ceiling and/or Floor Data R package DACF version 1.1.0 An implementation of data analytic methods in R for analyses for data with ceiling/floor effects. The package currently includes functions for mean/variance estimation and mean comparison tests. Implemented methods are from Aitkin (1964) <doi:10.1007/BF02289723> and Liu & Wang (2021) <doi:10.3758/s13428-020-01407-2>. Software Depends: R (>= 3.5) Imports: mvtnorm, qgraph, Matrix, psych, utils Suggests: knitr, rmarkdown, MASS, ggplot2 Qimin Liu <Qliuacademia@gmail.com> Comprehensive R Archive Network (CRAN) Qimin Liu [aut, cre], Lijuan Wang [aut], Lauren Trichtinger [aut], Grace Murray [ctb] GPL-2 2026-07-16 application/tgz https://CRAN.R-project.org/package=DACF doi:10.32614/CRAN.package.DACF