Dear listmembers,
I'm investigating the effect of inclination (Inc) on bloodpressure
(Bp) in different people(Id). I've got 15 min of averaged 6 sec epochs
(150 measurements) at each level of Inc (total of 6 levels). Bp at
each Inc and within each Id are obviously not independent, so I'm
trying to fit a model---.xtmixed Bp Inc || Id:Inc, cov(unstr)-- .
However a warning appears: Warning: convergence not achieved;
estimates are based on iterated EM. Is this due to the correlation
between the measurements and insufficient # of Id ?? In that case how
can I do a poweranalysis for this problem?
Regards,
Moleps
*
* For searches and help try:
* http://www.stata.com/help.cgi?search
* http://www.stata.com/support/statalist/faq
* http://www.ats.ucla.edu/stat/stata/
