% Generated by roxygen2: do not edit by hand
% Please edit documentation in R/negbin_helpers.R
\name{negbin_family}
\alias{negbin_family}
\title{Negative Binomial Family for lgspline}
\usage{
negbin_family()
}
\value{
A list with family components used by \code{lgspline}.
}
\description{
Creates a family-like object for NB2 regression. The link is log, the
variance function is \eqn{V(\mu) = \mu + \mu^2/\theta}, and the
dispersion stored by lgspline (\code{sigmasq_tilde}) is the shape
parameter \eqn{\theta}.
}
\details{
The NB2 model has a nuisance shape parameter \eqn{\theta} analogous
to the Weibull scale parameter. It is estimated jointly with
\eqn{\boldsymbol{\beta}} and its uncertainty is propagated via the
Schur complement correction.
}
\examples{
fam <- negbin_family()
fam$family
fam$link

}
