R> X <- data.frame(bad=1:3, worse=rnorm(3)) R> X bad worse 1 1 -2.440467 2 2 1.320113 3 3 -0.306639 R> colnames(X) <- c("good", "better") R> X good better 1 1 -2.440467 2 2 1.320113 3 3 -0.306639