st: adjusted counts after xtmepoisson

[rlhall@umich.edu]

I am running a crossed random effects model using xtmepoisson, after  
which I want to generate estimated counts and confidence intervals at  
different levels of X1 and X2.  The documentation suggests that the  
new "margins" command should be able to handle this -- it is listed as  
an option after xtmepoisson -- but I get the error message: "default  
prediction is a function of possibly stochastic quantities other than  
e(b)".  Using the "force" option only generates the error message:  
"data have changed since estimation"

xtmepoisson y x1 x2 || _all:R_group_j || group_i:, mle
(output omitted)
margins, predict(mu) atmeans


Thanks!
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