[R-sig-phylo] How to test stratification of sampling across tree?

Hi all, I'm interested in the distribution of a non-heritable binary trait/observation across a large tree 1000+ tip tree. The tree is non-distinct in shape and balance, it is neither fully pectinate nor fully balanced. It has many soft polytomies too. I believe the distribution of this trait to

Re: [R-sig-phylo] How to test stratification of sampling across tree?

Ross, An interesting question. I understand it as that you want to test if the trait is overdispersed relative to phylogeny, which still makes me think that measures of 'phylogenetic signal' might be still be useful, even though the typical interpretation is 'signal' as 'heritability'. I would try

Re: [R-sig-phylo] How to test stratification of sampling across tree?

Thanks Dave, I'll try Blomberg's K with small simulated fully-bifurcating trees of simple shape (e.g. fully pectinate), where I can easily paint the tips myself in what I believe to be a "maximally stratified manner" e.g. 010101010 to see if Blomberg's K does actually reach minimum (i.e. 0.0 ?

Re: [R-sig-phylo] How to test stratification of sampling across tree?

So I tried a 12-taxon fully pectinate tree with Blomberg's K as calculated by picante::Kcalc() library(picante) library(ape) aa<-"(A,(B,(C,(D,(E,(F,(G,(H,(I,(J,(K,L)));" t1<-read.tree(text=aa) t4 <- compute.brlen(t1,method="Grafen",1) tipvals <- c(0,1,0,1,0,1,0,1,0,1,0,1) Kcalc(tipvals,t4)