Box-Cox Symmetric Regression for Non-Negative Data R package BCSreg version 1.1.1 A collection of tools for regression analysis of non-negative data, including strictly positive and zero-inflated observations, based on the class of the Box-Cox symmetric (BCS) distributions and its zero-adjusted extension. The BCS distributions are a class of flexible probability models capable of describing different levels of skewness and tail-heaviness. The package offers a comprehensive regression modeling framework, including estimation and tools for evaluating goodness-of-fit. Software Depends: R (>= 3.5) Imports: distr, EnvStats, Formula, gamlss.dist, GeneralizedHyperbolic Suggests: testthat (>= 3.0.0) Rodrigo Medeiros <rodrigo.matheus@ufrn.br> Comprehensive R Archive Network (CRAN) Felipe Queiroz [aut] (ORCID: <https://orcid.org/0000-0001-8368-0707>), Rodrigo Medeiros [aut, cre, cph] (ORCID: <https://orcid.org/0000-0001-8101-3038>) GPL (>= 3) 2026-02-09 application/tgz https://CRAN.R-project.org/package=BCSreg doi:10.32614/CRAN.package.BCSreg