Thanks to Joshua and Erik for very helpful suggestions. This clarifies what I had found to be a tricky area of the documentation! Best wishes, Anthony Staines
-- Anthony Staines, Professor of Health Systems Research, School of Nursing, Dublin City University, Dublin 9, Ireland. Tel:- +353 1 7007807. Mobile:- +353 86 606 9713 ______________________________________________ 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.
