I believe that dozens of people asked this question before you. If you search this error in "google", you can find your answer!
Ozgur -- View this message in context: http://r.789695.n4.nabble.com/Merror-tp4632371p4632378.html Sent from the R help mailing list archive at Nabble.com. ______________________________________________ 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.