BioOne.org will be down briefly for maintenance on 17 December 2024 between 18:00-22:00 Pacific Time US. We apologize for any inconvenience.
How to translate text using browser tools
1 December 2009 Size-Correction and Principal Components for Interspecific Comparative Studies
Liam J. Revell
Author Affiliations +
Abstract

Phylogenetic methods for the analysis of species data are widely used in evolutionary studies. However, preliminary data transformations and data reduction procedures (such as a size-correction and principal components analysis, PCA) are often performed without first correcting for nonindependence among the observations for species. In the present short comment and attached R and MATLAB code, I provide an overview of statistically correct procedures for phylogenetic size-correction and PCA. I also show that ignoring phylogeny in preliminary transformations can result in significantly elevated variance and type I error in our statistical estimators, even if subsequent analysis of the transformed data is performed using phylogenetic methods. This means that ignoring phylogeny during preliminary data transformations can possibly lead to spurious results in phylogenetic statistical analyses of species data.

© 2009 The Society for the Study of Evolution.
Liam J. Revell "Size-Correction and Principal Components for Interspecific Comparative Studies," Evolution 63(12), 3258-3268, (1 December 2009). https://doi.org/10.1111/j.1558-5646.2009.00804.x
Received: 25 February 2009; Accepted: 1 July 2009; Published: 1 December 2009
JOURNAL ARTICLE
11 PAGES

This article is only available to subscribers.
It is not available for individual sale.
+ SAVE TO MY LIBRARY

KEYWORDS
data transformation
evolutionary regression
least squares
linear regression
PCA
PHYLOGENETIC COMPARATIVE METHODS
principal components analysis
RIGHTS & PERMISSIONS
Get copyright permission
Back to Top