Prior to the steps below, enter the data as appropriate for the analyses (described elsewhere). As always, the following commands should be typed directly in the R console window.
Get the mean and standard deviation for the dependent variable for each of the levels.
by(Outcome,Factor,mean)
by(Outcome,Factor,sd)
Test the mean difference for statistical significance and get its confidence interval.
t.test(Outcome~Factor,var.equal=T)