Hi all, I created a data frame with three factors, plus the response that looks like this:
x1 x2 x3 y a 1 1 0.3 a 2 1 0.1 b 1 1 0.4 c 4 3 0.1 ... I would like to analise the effect of two of them, keeping the third fixed (I already know the effect of the last). The reason why I don't create several data frames for each value of the thirs factor is simply convenience (I'd like to be able to decide which factor I want to rule out) for example I'd like to write something like boxplot(y ~ x1 + x2, x3 == 1) which of course doesn't work, otherwise I wouldn't write :-) Is this possible and how? Thank you Giampiero ______________________________________________ [EMAIL PROTECTED] mailing list https://www.stat.math.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
