Bivariate Zero-Inflated Count Models Using Copulas R package bizicount version 1.3.4 Maximum likelihood estimation of copula-based zero-inflated (and non-inflated) Poisson and negative binomial count models, based on the article <doi:10.18637/jss.v109.i01>. Supports Frank and Gaussian copulas. Allows for mixed margins (e.g., one margin Poisson, the other zero-inflated negative binomial), and several marginal link functions. Built-in methods for publication-quality tables using 'texreg', post-estimation diagnostics using 'DHARMa', and testing for marginal zero-modification via <doi:10.1177/0962280217749991>. For information on copula regression for count data, see Genest and Nešlehová (2007) <doi:10.1017/S0515036100014963> as well as Nikoloulopoulos (2013) <doi:10.1007/978-3-642-35407-6_11>. For information on zero-inflated count regression generally, see Lambert (1992) <https://www.jstor.org/stable/1269547>. The author acknowledges support by NSF DMS-1925119 and DMS-212324. Software Depends: R (>= 4.1.0) Imports: pbivnorm (>= 0.6.0), Formula (>= 1.2-4), rlang (>= 0.4.7), MASS (>= 7.3-54), numDeriv (>= 2016.8-1.1), methods, stats, utils, DHARMa (>= 0.3.4), texreg (>= 1.37.5) Suggests: covr, testthat (>= 3.0.0) John Niehaus <jniehaus2257@gmail.com> Comprehensive R Archive Network (CRAN) John Niehaus [aut, cre] GPL (>= 3) 2025-08-20 application/tgz https://CRAN.R-project.org/package=bizicount doi:10.32614/CRAN.package.bizicount