Try the fit.contrast() and estimable() functions from my gregmisc package, or the contrasts() function in Frank Harrell's Design package.
-Greg > -----Original Message----- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] Behalf Of Kimberly Ann > Fernandes > Sent: Monday, May 31, 2004 1:10 PM > To: [EMAIL PROTECTED] > Subject: [R] Contrasts > > > Hello, > > I am trying to figure out how to conduct a t-test on a > specific contrast > for my data. I have four factors in my data and would like > to conduct a > t-test on the average of the data from the first two factors > against the > average of the data on the second two factor (i.e. is the > average of the > first two different from the average of the second two). Is there a > quick way to do this? I found the contrast function, but wasn't sure > how to apply it. > > Thank you, > Kim > > ______________________________________________ > [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 > LEGAL NOTICE\ Unless expressly stated otherwise, this messag...{{dropped}} ______________________________________________ [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