[R] Change title size in plot(model)?

I want to use the plot(model) function to generate Tukey-anscomb and Q-Q plots of a lm(). I manage to change all labels but the main one which apparently is neither main or sub. So far I have tried as par setting: cex (changes symbol size within the plot), cex.main (no effect), cex.sub (no effec

[R] Create grouping from TukeyHSD (as a duncan test does)?

Hello everybody 1. If there is/ever will be a function to perform "duncan multiple range test" please inform me at once. 2. Is there a way to create a grouping as duncan does from TukeyHSD output? My experimental design contained 62 genotypes, so the pairwise comparison is not that usefull and