Hi I am having problems using na.action=na.include in a nlme call. Basically I am trying to run a particular model without including any covariates but my dataset does include some covariates (factors) with missing values. My understanding from the Pinheiro and Bates book is that one would use na.action=na.include in order to treat the missing values as another factor level and then one can also use naPattern to specify which rows must be excluded from the calculation of the objective function.
I have tried this but keep getting error messages about being unable to find the object or the function "na.include". I have also tried to replicate the particular Phenobarbital example verbatim from the book but am getting the same error message. Could it be that my version of the nlme package is outdated? I also cannot find any help on na.include... Thanks Greg ______________________________________________ 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