On Wednesday 6. March 2013 14.50.23 Ben Bolker wrote: > Just a quick thought (sorry for removing context): what happens if > you use sum-to-zero contrasts throughout, i.e. > options(contrasts=c("contr.sum", "contr.poly")) ... ?
Ah, I've got it now, this pointed me in the right direction. Thanks a lot! For future reference, the default was "contr.treatment", which implies > contrasts(leaf$B) + - 0 + 1 using contr.sum, we get > contrasts(leaf$B) [,1] - 1 + -1 which is orthogonal, and also explains the switched sign. Kjetil ______________________________________________ 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.