Scalar estimate of the relative risk \(q\) for zero-inflated Poisson data.
estimate_zip_relrisk(d, mu, y)A vector of indicator variables for whether the corresponding count
in the argument y is an excess zero or not. Can also be estimates
of these indicators.
A vector of given/estimated Poisson expected value parameters, of
same length as d.
An integer vector of the observed counts, of same length as
d.
A scalar, the estimated relative risk.