Dear Gang, The problem was in the model.matrix.lme() method provided by the car package, and is now fixed in the development version of the car package on R-Forge. You should be able to install it from there via install.packages("car", repos="http://R-Forge.R-project.org") after the package is next built on R-Forge, usually in a day or so.
Best, John > -----Original Message----- > From: R-help [mailto:r-help-boun...@r-project.org] On Behalf Of Gang Chen > Sent: January-13-15 1:48 PM > To: r-help > Subject: [R] Problem with Anova() in package "car" > > I'm having some trouble with Anova() in package "car". When the model > formula is explicitly expressed: > > library('nlme') > library('car') > fm <- lme(distance ~ age + Sex, data = Orthodont, random = ~ 1) > > Anova() works fine: > > Anova(fm) > > However, if the model formula is scanned from an external source: > > myModel <- as.formula("distance ~ age + Sex") > fm2 <- lme(myModel, data = Orthodont, random = ~ 1) > > I get the following error: > > Anova(fm2) > Error: object of type 'symbol' is not subsettable > > How to resolve the situation when the model formula is defined externally? > > Thanks, > Gang > > ______________________________________________ > R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see > 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. --- This email has been checked for viruses by Avast antivirus software. ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see 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.