Re: [R] Pairwise T-Tests and Dunnett's Test (possibly using multcomp)

Hi Josh,   Thanks for your reply. You're right about letting R's method dispatch system choose the method for summary and inserting more spaces in the code. I was just messing around with the code in the former case and forgot to change it back. As far as not having enough whitespace goes, I've

Re: [R] Pairwise T-Tests and Dunnett's Test (possibly using multcomp)

Hi Paul, Changing the factor levels will work (as you saw). In this case, you could also edit the contrast matrix. ## look at default contrasts contrasts(gad$dosegrp) model1 <- lm(hama ~ dosegrp, data = gad) summary(model1) ## choose group 3 as base (comparison) contrasts(gad$dosegrp) <- contr.

[R] Pairwise T-Tests and Dunnett's Test (possibly using multcomp)

Hello Everyone,   Figured out one part of the code. Setting the reference level for a factor is accomplished using the relevel funtion (pg. 383 of MASS; pg. 70 of Data Manipulation with R):   gad$dosegrp <- relevel(gad$dosegrp,3)   This works very well. Much better than using a format in SAS proc

[R] Pairwise T-Tests and Dunnett's Test (possibly using multcomp)

Hello Everyone,   I've been learning to use R in my spare time over the past several months. I've read about 7-8 books on the subject. Lately I've been testing what I've learned by trying to replicate the analyses from some of my SAS books. This helps me make sure I know how to use R properly an