Lucy: Why are you interested in robust standard errors from lme? Typically, robust standard errors are sought when there is model misspecification due to ignoring some covariance among units with a group.
But, a mixed model is designed to directly account for covariances among units within a group such that the standard errors more adequately represent the true sampling variance of the parameters. So, the lme standard errors are robust in a sense that they are presumably correct if you have your model correctly specified. It would do better service to explain your issue a little more to get better help. Harold > -----Original Message----- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] On Behalf Of Lucy Radford > Sent: Tuesday, August 07, 2007 8:17 AM > To: r-help@stat.math.ethz.ch > Subject: [R] Robust Standard Errors for lme object > > Hi > > I have fitted a linear mixed model using the lme function but > now wish to calculate robust standard errors for my model. I > have been able to find several functions which calculate > robust s.e for lm objects but have not been able to find a > function which calcualtes robust s.e for lme objects. Would > anyone know of a function that will allow me to do this. > > Many Thanks > > Lucy > > ______________________________________________ > R-help@stat.math.ethz.ch 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. > ______________________________________________ R-help@stat.math.ethz.ch 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.
