Categorical Instrumental Variables R package civ version 0.1.0 Implementation of the categorical instrumental variable (CIV) estimator proposed by Wiemann (2023) <arXiv:2311.17021>. CIV allows for optimal instrumental variable estimation in settings with relatively few observations per category. To obtain valid inference in these challenging settings, CIV leverages a regularization assumption that implies existence of a latent categorical variable with fixed finite support achieving the same first stage fit as the observed instrument. Software Depends: R (>= 3.6) Imports: stats, AER, kcmeans Suggests: testthat (>= 3.0.0), covr, knitr, rmarkdown Thomas Wiemann <wiemann@uchicago.edu> Comprehensive R Archive Network (CRAN) Thomas Wiemann [aut, cre] GPL (>= 3) 2023-12-08 application/tgz https://CRAN.R-project.org/package=civ doi:10.32614/CRAN.package.civ