Seeing distinct groups where there are none: spurious patterns from between-group PCA

A Cardini, P O'Higgins, FJ Rohlf - Evolutionary Biology, 2019 - Springer
Using sampling experiments, we found that, when there are fewer groups than variables,
between-groups PCA (bgPCA) may suggest surprisingly distinct differences among groups …

Cross-validated between group PCA scatterplots: A solution to spurious group separation?

A Cardini, PD Polly - Evolutionary Biology, 2020 - Springer
Between group PCA (bgPCA) has been developed to summarize group differences in high
dimensional spaces like in geometric morphometrics and microarray data where the number …

Permutation tests for phylogenetic comparative analyses of high-dimensional shape data: what you shuffle matters

DC Adams, ML Collyer - Evolution, 2015 - academic.oup.com
Evaluating statistical trends in high-dimensional phenotypes poses challenges for
comparative biologists, because the high-dimensionality of the trait data relative to the …

[HTML][HTML] Pathologies of between-groups principal components analysis in geometric morphometrics

FL Bookstein - Evolutionary Biology, 2019 - Springer
Good empirical applications of geometric morphometrics (GMM) typically involve several
times more variables than specimens, a situation the statistician refers to as “high p/n,” …

Phylogenetic ANOVA: group-clade aggregation, biological challenges, and a refined permutation procedure

DC Adams, ML Collyer - Evolution, 2018 - academic.oup.com
Phylogenetic regression is frequently used in macroevolutionary studies, and its statistical
properties have been thoroughly investigated. By contrast, phylogenetic ANOVA has …

Controlling for non-independence in comparative analysis of patterns across populations within species

GN Stone, S Nee, J Felsenstein - … Transactions of the …, 2011 - royalsocietypublishing.org
How do we quantify patterns (such as responses to local selection) sampled across multiple
populations within a single species? Key to this question is the extent to which populations …

[HTML][HTML] Discriminant analysis of principal components: a new method for the analysis of genetically structured populations

T Jombart, S Devillard, F Balloux - BMC genetics, 2010 - Springer
Background The dramatic progress in sequencing technologies offers unprecedented
prospects for deciphering the organization of natural populations in space and time …

Uncertainties due to within-species variation in comparative studies: measurement errors and statistical weights

LZ Garamszegi - Modern phylogenetic comparative methods and their …, 2014 - Springer
Comparative studies investigating evolutionary questions are generally concerned with
interspecific variation of trait values, while variations observed within species are inherently …

Size-correction and principal components for interspecific comparative studies

LJ Revell - Evolution, 2009 - academic.oup.com
Phylogenetic methods for the analysis of species data are widely used in evolutionary
studies. However, preliminary data transformations and data reduction procedures (such as …

Using the AMOVA framework to estimate a standardized genetic differentiation measure

PG Meirmans - Evolution, 2006 - Wiley Online Library
Abstract Comparison of population structure between studies can be difficult, because the
value of the often‐used FST‐statistic depends on the amount of genetic variation within …