[R-sig-ME] Cholmod warning with glmer

[leanne heisler]

Hi All,
I am running a generalized linear mixed effects model with lme4 and am getting an error I have not been able to decipher. I was hoping for some guidance. I am using the following code:

> glmer(DM~PREC+(1|NEST)+(1|NG)+(1|LONG),data=data,family=poisson,verbose=TRUE)
 0: 6107.8287: 1.34084 1.29515 0.532795 3.23218 -0.00145626
 1: 6107.8287: 1.34084 1.29515 0.532795 3.23218 -0.00145626
Error in mer_finalize(ans) : Downdated X'X is not positive definite, 1.
In addition: Warning messages:
1: In mer_finalize(ans) :
 Cholmod warning 'not positive definite' at file:../Cholesky/t_cholmod_rowfac.c, line 431
2: In mer_finalize(ans) :
 Cholmod warning 'not positive definite' at file:../Cholesky/t_cholmod_rowfac.c, line 431
All fixed and random effects are continuous variables (DM is counts of deer mice) except for the random effect 'NEST', which is categorical. The model runs fine when the random effects NEST and LONG are removed.

I feel I am doing something wrong here and would greatly appreciate any help from this mailing list.

Thank you in advance.
---------------
 Leanne Heisler
 Graduate Student
 Department of Biology
 University of Regina