Folks, we apologize for the delayed announcement but wanted the morphometrics community to be aware of a new paper we have recently published. We compared two methods for performing phylogenetic regression using shape data (PIC vs D-PGLS). In it we demonstrate that while test statistics from both are the same (SS, MS, F etc), P-values can differ dramatically. The reason is that current randomization tests with PIC-based methods use an incorrect permutation procedure, which results in very high type I error rates. We discuss this relative to correct exchangeable units for permutation procedures, and provide a solution.
Here are the paper details: Adams, DC and Collyer, ML. 2015. Permutation tests for phylogenetic comparative analyses of high-dimensional shape data: What you shuffle matters. Evolution 69 (3): 823-829. (March 2015 issue) Warm regards! Michael Collyer Associate Professor Biostatistics Department of Biology Western Kentucky University 1906 College Heights Blvd. #11080 Bowling Green, KY 42101-1080 Phone: 270-745-8765; Fax: 270-745-6856 Email: [email protected]<mailto:[email protected]> -- MORPHMET may be accessed via its webpage at http://www.morphometrics.org To unsubscribe from this group and stop receiving emails from it, send an email to [email protected].
