st: xtmixed output

[Gabriele Schino <gschino@casaccia.enea.it>]

Dear Statalisters,

I have a (possibly silly) question about the output provided by xtmixed.

In testing the significance of the individual independent variables 
xtmixed provides a z value and a P value. This is in contrast with, 
for example, xtreg, that provides t, df and P values.

My question is: given that my sample is obviously finite, shouldn't 
xtmixed test significance using a statistic (like t) for finite 
samples? How do I attach a df to my test?

Thank you very much for your help.

All the best,
Gabriele Schino

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