st: Marginal effects in negative binomial models

["Corey Phelps" <cphelps@u.washington.edu>]

I am trying to calculate marginal effects using the "mfx commute" command
for a xtnbreg model. Because mfx computes marginal effects from the
post-estimated linear predictions, it returns the regresssion betas as
marginal effects. However, I am interested in the marginal effect (e^BX)Bj,
evaluated at the sample means of the covariates. How do I go about obtaining
this? 

Corey Phelps

*
*   For searches and help try:
*   http://www.stata.com/support/faqs/res/findit.html
*   http://www.stata.com/support/statalist/faq
*   http://www.ats.ucla.edu/stat/stata/