I've been using the PSCL zero-inflated negative binomial model to simply fit count data. I'm not specifying any complex formula, essentially I just provide the count data and try to find the parameters of the underlying zero-inflated NB distribution (that I think) is generating the obtained counts. Like below,
pscl::zeroinfl(formula = counts ~ 1, data = df, dist = "negbin")
I am trying to better understand how this fitting works, and I was specifically wondering how the PSCL package computes the parameters of a ZINB model? Does it use MLE or MOM? Would appreciate any pointers on this, and also even any links to the exact solutions written out for the fit. Thanks!