thank you all, Jagat, Bert and Prof. Ripley for your kind help. The PROBLEM was:
give descripitve names to the columns in JJ<-data.frame( c( as.character(rep( gender,3))) , c( F76,6- F83, F90) ) Possible SOLUTIONs are: 1. JJ <- data.frame( gender=c( as.character(rep( gender,3))) , J.value=c(F76,6- F83, F90) ) 2. names(JJ) <- c("gender","J.value") Now I can continue my work being happy with R. hth Wolfgang ______________________________________________ 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.