Re: [R-sig-phylo] understanding variance-covariance matrix

2018-08-27 Thread Theodore Garland
us mentioned references illustrated with > > some simulations. > > Hope it may helps... > > > > Best, > > > > Julien > > > > -- > > *De :* R-sig-phylo de la part de > > Andrew Hipp > > *Envoyé :* dim

Re: [R-sig-phylo] understanding variance-covariance matrix

2018-08-27 Thread Agus Camacho
p > *Envoyé :* dimanche 26 août 2018 05:36 > *À :* bome...@utk.edu > *Cc :* mailman, r-sig-phylo; Agus Camacho > *Objet :* Re: [R-sig-phylo] understanding variance-covariance matrix > > I'll second Brian's self-citation. O'Meara et al. 2006 is I think one of > the best introdu

Re: [R-sig-phylo] understanding variance-covariance matrix

2018-08-26 Thread Julien Clavel
trated with some simulations. Hope it may helps... Best, Julien De : R-sig-phylo de la part de Andrew Hipp Envoy� : dimanche 26 ao�t 2018 05:36 � : bome...@utk.edu Cc : mailman, r-sig-phylo; Agus Camacho Objet : Re: [R-sig-phylo] understanding variance-cova

Re: [R-sig-phylo] understanding variance-covariance matrix

2018-08-25 Thread Andrew Hipp
I'll second Brian's self-citation. O'Meara et al. 2006 is I think one of the best introductions to the phylogenetic covariance matrix, and I often direct students to it. Brian's point about the relationship between observed and expected covariance is illustrated here in a brief note I wrote up

Re: [R-sig-phylo] understanding variance-covariance matrix

2018-08-25 Thread Emmanuel Paradis
Hi Agus & Brian, To complete Brian's response, vcv() is a generic function which works with trees (class "phylo") and phylogenetic correlation structures (class "corPhyl"). The latter can be used to define an OU model, see ?vcv, and ?corPhyl for the correlation structures available in ape.

Re: [R-sig-phylo] understanding variance-covariance matrix

2018-08-25 Thread Brian O'Meara
Hi, Agus. The variance-covariance matrix comes from the tree and the evolutionary model, not the data. Each entry between taxa A and B in the VCV is how much covariance I should expect between data for taxa A and B simulated up that tree using that model. I don't want to be *that guy*, but O'Meara