Abdus Sattar said the following on 9/19/2007 7:03 AM: > Dear R-Users: > > I am trying to find the robust (or sandwich) estimates of the standard error > of fixed effects parameter estimates using the package "lmer2". In model-1, I > used "robust=TRUE" on the other, in model-2, I used "robust=FALSE". Both > models giving me the same estimates. So my question is, does the robust > option works in lmer2 to get the robust estimates of the standard error? If > anybody could offer me a suggestion I would greatly appreciate it. Thank you. > > > Model-1: > >> p.mle<-lmer2(ddimer~race+steroid+psi+sofa+apache + (apache|subject), >> method="ML", data=final, robust=TRUE, cluster="id", weights=final$w) >> beta=fixef(p.mle) >> Vcov=vcov(p.mle, useScale=FALSE) >> se=sqrt(diag(Vcov)) >> beta > (Intercept) race steroid psi sofa apache > 5.826489820 -0.001920670 -0.242040171 0.005293996 0.075468340 0.009245152 >> se > [1] 0.108325229 0.058921371 0.055975547 0.001285687 0.018119089 0.002559902 > > Model-2: > >> p.mle<-lmer2(ddimer~race+steroid+psi+sofa+apache + (apache|subject), >> method="ML", data=final, robust=FALSE, cluster="id", weights=final$w) >> beta=fixef(p.mle) >> Vcov=vcov(p.mle, useScale=FALSE) >> se=sqrt(diag(Vcov)) >> beta > (Intercept) race steroid psi sofa apache > 5.826489820 -0.001920670 -0.242040171 0.005293996 0.075468340 0.009245152 >> se > [1] 0.108325229 0.058921371 0.055975547 0.001285687 0.018119089 0.002559902 > > > Best Regards, > > Sattar > >
The help page to ?lmer2 in the lme4 package makes no mention of "cluster" or "robust" arguments. To me, that would mean these arguments are ignored. HTH, --sundar ______________________________________________ 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.
