Hello, and sorry for asking a question without the data - hope it can still be answered:
I've run two things on the same data: # Using lme: mix.lme <- lme(DV ~a+b+c+d+e+f+h+i, random = random = ~ e+f+h+i| group, data = mydata) # Using lmer mix.lmer <- lmer(DV ~a+b+c+d+(1|group)+(e|group)+(f|group)+(h|group)+(i|group), data = mydata) lme provided an output (fixed effects and random effects coefficients). lmer gave me an error: Error in mer_finalize(ans) : Downdated X'X is not positive definite, 10. I've rerun lmer with - but specifying the random effects for 2 fewer predictors. This time it ran and provided an output. (BTW, the random effects of lmer with 2 fewer predictors specified as random were very close to the output of lme). Question: Looks like lmer could not invert the matrix, right? But how come lme (which I thought was an earlier version of lmer) COULD invert it? Greatly appreciate a clarification! -- Dimitri Liakhovitski Ninah Consulting www.ninah.com ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
