st: ztnb missing values from regression output

[Megan McKeown <mmckeown@uwo.ca>]

Hello Statalist,

I am running a zero-truncated negative binomial regression using the option 'cluster'. The output gives no values for the standard error of alpha and lnalpha and no values for the confidence intervals. When I run this regression omitting the 'cluster' option these values are present. Any suggestions as to what is causing this?

Thanks,

Megan