st: xtmelogit models are dropping clusters

[Katie Brooks Biello <katie.biello@yale.edu>]

Hi all -
I am using xtmelogit on multiply imputed data (mi estimate: xtmelogit)  
to run a series of random coefficient models (random intercept and one  
random slope). I have run a dozen or so models, where I add blocks of  
covariates to each subsequent model. I have 4323 individuals nested  
within 110 clusters. The first 5 models correctly indicated that I had  
110 clusters. However, after including another set of covariates, my  
subsequent model seemed to have dropped 5 clusters (and the  
individuals in these clusters). There was no error/warning, and I  
checked to make sure that there was not missing data on those  
variables (there is not). Does anyone have any idea what could be  
going on or how I can begin to figure it out? I'm new to Stata so I  
may be missing some straightforward diagnostic tools.

Thank you in advance,
Katie

Katie Brooks Biello, MPH
PhD Candidate
Yale University
School of Epidemiology and Public Health




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