Re: [R] Robust estimation of variance components for a nested design

If you mean using random effects which have a fat-tailed distribution this has been available in AD Model Builder's random effects package for some time now. The general idea is to start with a random effect assumed to be standard normal and then to transform it by the cumulative dist function for

Re: [R] Robust estimation of variance components for a nested design

Sue-- Check out the heavy package on CRAN, which implements the robust mixed-effects models that Andy mentioned. The package is relatively new and is still being developed, but worth a look. cheers, Dave I believe Pinhiero et al published a paper in JCGS a few years back on the subject, m

Re: [R] Robust estimation of variance components for a nested design

I believe Pinhiero et al published a paper in JCGS a few years back on the subject, modeling the random effects with t distributions. No software were publicly available, as far as I know. Andy From: S Ellison > Sent: Thursday, March 11, 2010 9:56 AM > To: r-help@r-project.org > Subject: [R] Ro