vegan::adonis, SS, order of terms
Thanks for reminding me about the behavior of stats::anova under unbalanced designs. I had forgotten that equations 5 and 6 in Anderson 2001 are only for balanced designs. Oliver
On Wed, Feb 1, 2012 at 2:40 AM, Jari Oksanen <jari.oksanen at oulu.fi> wrote:
On 01/02/2012, at 06:52 AM, Oliver Soong wrote:
Are the vegan::adonis sums of squares supposed to depend on the order of the terms?
Yes, the terms are added sequentially, just like in ordinary R anova, and they are order-dependent. The next release version of vegan will show this information (I just committed the change to R-Forge).
I'm trying to understand permutational MANOVA, and this disagrees with my reading of Anderson 2001. library(vegan) data(dune) data(dune.env) adonis(dune ~ A1 + Management, dune.env) adonis(dune ~ Management + A1, dune.env)
So *how* does this disagree with your reading? Cheers, Jari Oksanen -- Jari Oksanen, Dept Biology, Univ Oulu, 90014 Finland