Dear Karla,

There are several options for classical phylogenetic regressions. For instance, 
the �gls� function from nlme package with the �corStruct� objects from ape, the 
function �phylolm� from the package of the same name or �pgls� in caper to name 
a few. For multivariate data you can use �mvgls� in mvMORPH.

Note however that the goal of these comparative approaches is to provide valid 
confidence interval or p-values associated to parameter estimates rather than 
�phylogenetically corrected� slopes or intercepts. Both ordinary least squares 
coefficients (conventional non-phylogenetic regressions or OLS) and generalized 
least squares (GLS � phylogenetic regressions) might slightly differ but are as 
good as any (they�re unbiased - at least assuming that both errors and 
predictors are independent and known without errors). However, their variance 
may differ substantially and impact the statistical performances of the 
regressions.

Best wishes,

Julien

________________________________
De : R-sig-phylo <r-sig-phylo-boun...@r-project.org> de la part de Karla Shikev 
<karlashi...@gmail.com>
Envoy� : dimanche 28 juin 2020 15:35
� : R Sig Phylo Listserv <r-sig-phylo@r-project.org>
Objet : [R-sig-phylo] regression slopes

Dear friends,

What would be your suggestion for the best PCM to obtain
"phylogenetically-corrected" slopes and intercepts of a relationship
between two continuous variables?

Karla

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