[R-sig-ME] lme error message

[Stuart Luppescu]

Running a nested model with lme, and getting this message:

Error in MEEM(object, conLin, control$niterEM) : 
  Singularity in backsolve at level 0, block 1

Can anyone explain this?

Thanks.
-- 
Stuart Luppescu -=- slu .at. ccsr.uchicago.edu        
University of Chicago -=- CCSR 
才文と智奈美の父 -=-    Kernel 2.6.28-gentoo-r5                
Xander: What's going on here? People are going all 
 Felicity with  their hair.