glmmPQL Question
On 12-06-04 05:38 PM, John Michel wrote:
Ben
I have always had an issue getting VarCorr to work with any program working from lme4. Here is the error message I get when I try to calculate the VarCorr
VarCorr(Model.A2)
Error in VarCorr(Model.A2) : error in evaluating the argument 'x' in selecting a method for function 'VarCorr' Thanks for any additional suggestions you have for me... John
Do you have nlme loaded at the same time? Does VarCorr() work if you
detach("package:nlme")? What is the result of sessionInfo()? I can't
quite reproduce your error, but if I load nlme after lme4 I can get
Error in UseMethod("VarCorr") :
no applicable method for 'VarCorr' applied to an object of class "mer"
From ?glmmPQL: x <- glmmPQL(y ~ trt + I(week > 2), random = ~ 1 | ID, family = binomial, data = bacteria) VarCorr(x) ID = pdLogChol(1) Variance StdDev (Intercept) 1.9898963 1.4106368 Residual 0.6084797 0.7800511 You probably already know that the object returned by VarCorr() has a slightly weird format. I don't know where your second line, GRPpdSymm(1) comes from?? VarCorr() should work just fine on lmer objects too. Perhaps you can give a reproducible example of what you've tried/ what fails for you? ---------------------------------------------------------- John W. Michel, Ph.D. Assistant Professor of Management Sellinger School of Business & Management Loyola University Maryland 4501 N. Charles Street Baltimore, MD 21201 jwmichel at loyola.edu