Hi all, In the (very simple) example below, I have defined a random effect for the residuals in lme(). So the model is equivalent to a FIXED effect model. Could someone explain to me why lme() still gives two standard deviation estimates? I would expect lme() to return either: a) an error or a warning for having an unidentifiable model; b) only one standard deviation estimate.
Thank you for your time. Jerome Asselin > library(nlme) > simdat <- data.frame(A=1:4,Y=c(23,43,11,34)) > simdat A Y 1 1 23 2 2 43 3 3 11 4 4 34 > lme(Y~1,data=simdat,random=~1|A) <...snip...> Random effects: Formula: ~1 | A (Intercept) Residual StdDev: 12.96007 4.860027 <...snip...> > summary(lm(Y~1,data=simdat))$sigma [1] 13.84136 > sqrt(12.96007^2+4.860027^2) [1] 13.84136 ______________________________________________ [EMAIL PROTECTED] mailing list https://www.stat.math.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html