Hi All, I have used glm to model my data, I have two factors and a covariate as described in the example code below (mod.1).
I have been able to "force" glht to perform multiple comparisons by creating a combined variable for the factors, accepting that there will be a loss of statistical power as it seems to do what I want. I then use the cld function to generate the letters of significance from the glht which I can then apply to my figures with ggplot2. However when it comes to describing my data I am becoming increasingly suspicious that this hasn't worked as I want it too as the letters don't always make sense in relation my original model. Is there any other way of doing this on my original model (mod.1) rather than having to "cheat" (mod.2)? mod.1 <- glm(response ~ 1 + treat + seas + covariate, data = dat) # combined variable for pairwise comparisons treat.seas <- (as.numeric(dat$treat) * 10) + as.numeric(dat$seas) dat$treat.seas <- factor(treat.seas) mod.2 <- glm(response ~ 1 + treat.seas + covariate, data = dat) mod.2_glht <- glht(mod.2, linfct = mcp(treat.seas = "Tukey")) letters_mod.2 <- cld(mod.2_glht) Thank you in advance Melanie -- View this message in context: http://r.789695.n4.nabble.com/glht-multiple-comparisons-for-glm-with-2-factors-tp4633365.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.
