st: Insufficient Observations error(2001) with out-of-sample predictions

[Stephen Mennemeyer <smennemeyer@ms.soph.uab.edu>]

I am attempting to make out-of-sample predictions using the approach 
described in [R] predict  (pages 219-220). 
I estimated a model

gllamm y x1 x2 x3......

later I call up a second dataset of 18 hypothetical observations:

use newdata, clear

then I try to get predicted values

predict newvar, xb

I get back

 error  . . . . . . . . . . . . . . . . . . . . . . .  Return code 2001
       insufficient observations;
       You have requested some statistical calculation and, while there
       are some observations, the number is not sufficient to carry out
       your request.
The same problem occurs if  I use an alternative method of prediction:
gllapred newvar, xb

I have checked to see that I have the same variables in my dataset as in 
the estimated model. Variable names are in the correct case. The 
internal order of the variables in my second dataset is a bit different 
from the original, but the manual seems to say that this is ok. "ereturn 
list"  shows that the parameters for the estimated model  are still in 
memory.
Why this error?    
--
Stephen T. Mennemeyer Ph.D.
University of Alabama at Birmingham
School of Public Health
Dept. of Health Care Organization and Policy

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e-mail: smenneme@uab.edu


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