Ah. I see. So, if I want to test to see whether each simple effect is different from 0, I would do something like the following:
cm2 <- rbind( "A:L" = c(1, 0, 0, 0, 0, 0), "A:M" = c(1, 1, 0, 0, 0, 0), "A:H" = c(1, 0, 1, 0, 0, 0), "B:L" = c(1, 0, 0, 1, 0, 0), "B:M" = c(1, 1, 0, 1, 1, 0), "B:H" = c(1, 0, 1, 1, 0, 1)) summary(glht(fm, linfct = cm2), test = adjusted(type="none")) Correct? What is the df on those t-tests then? Is it 48? Interestingly, I find this produces results no different than fm2<-lm(breaks ~ tension:wool+0, data=warpbreaks) summary(fm2) Also, here, it would seem each t-test was done with the full 48df. Hrm. Chuck Cleland wrote: > > > Each column corresponds to one of the coefficients in the model, and > each row specifies a particular contrast. The numbers in the matrix > indicate how the model coefficients are combined to indicate a > particular difference in means. > For example, the first row indicates that the third coefficient > (woolB) is multiplied by -1. The baseline categories are A and L for > the wool and tension factors, so the woolB effect in fm is the simple > effect of B vs. A in the baseline category of the tension factor. > Multiplying this coefficient by -1 produces an A vs. B comparison in the > baseline category of the tension factor. > > > -- View this message in context: http://www.nabble.com/Asking%2C-are-simple-effects-different-from-0-tp15835552p15855630.html Sent from the R help mailing list archive at Nabble.com. ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
