Estimation of a Variety of Count Regression Models // An implementation of multiple regression models for count data. These include various forms of the negative binomial (NB-1, NB-2, NB-P, generalized negative binomial, etc.), Poisson- Lognormal, other compound Poisson distributions, the Generalized Waring model, etc. Information on the different forms of the negative binomial are described by Greene (2008) doi:10.1016/j.econlet.2007.10.015. For treatises on count models, see Cameron and Trivedi (2013) doi:10.1017/CBO9781139013567 and Hilbe (2012) doi:10.1017/CBO9780511973420. For the implementation of under- reporting in count models, see Wood et al. (2016) doi:10.1016/j.aap.2016.06.013. For prediction methods in random parameter models, see Wood and Gayah (2025) doi:10.1016/j.aap.2025.108147. For estimating random parameters using maximum simulated likelihood, see Greene and Hill (2010) doi:10.1108/S0731-9053(2010)26; Gourieroux and Monfort (1996) doi:10.1093/0198774753.001.0001; or Hensher et al. (2015) doi:10.1017/CBO9781316136232.