Is there a sample code available to run random effect zero inflated negative binomial model for count data?
I found a program for random effect zero inflated poison from here: https://stats.oarc.ucla.edu/sas/faq/how-do-i-run-a-random-effect-zero-inflated-poisson-model-using-n...
How to modify it to run negative binomial zero inflated data? code was pasted below. Thank you!
proc nlmixed data = hdp method=gauss qpoints=25;
parms b0=1.0569 b1=-0.0020 b2=0.0094 b3=0.0122 b4=0.0239 b5=0.0530 b6=0.1322
a0=-1.6766 a1=-0.0116 a2=0.7479 a3=1.2588 a4=-0.8077 a5=-2.1410 a6=-2.7530
sigma2=0.2414;
logit0 = a0 + a1*Age + a2*SmokingHx2 + a3*SmokingHx3 +
a4*CancerStage2 + a5*CancerStage3 + a6*CancerStage4;
prob0 = 1 / (1 + exp(-logit0));
mu = exp(b0 + u + b1*Age + b2*LengthofStay + b3*BMI +
b4*CancerStage2 + b5*CancerStage3 + b6*CancerStage4);
if nmorphine = 0 then
ll = log(prob0 + (1 - prob0)*exp(-mu));
else
ll = nmorphine*log(mu) + log(1 - prob0) - mu - lgamma(nmorphine + 1);
model nmorphine ~ general(ll);
random u ~ normal(0, sigma2) subject=DID;
run;
