I would use aov( ) mod<-aov(Score~Group, data=x) summary(mod)
JJ -- View this message in context: http://n4.nabble.com/t-test-tp1470539p1470558.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.