Did someone knows a SAS/IML module that computes the log-likelihood function of the negative binomial distribution (pdf)?
Wikipedia has the equations for the log-likelihood:
Negative binomial distribution - Wikipedia, the free encyclopedia
You can call the DIGAMMA function in SAS: http://support.sas.com/documentation/cdl/en/lrdict/64316/HTML/default/viewer.htm#a000245889.htm
The use the basic outline provided in my article
Maximum likelihood estimation in SAS/IML - The DO Loop
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