Introducing multiple factor analysis (MFA) as a diagnostic taxonomic tool complementing principal component analysis (PCA)

Multiple factor analysis (MFA) is introduced as a diagnostic tool for taxonomy and discussed using examples from the herpetological literature. Its methodology and output are compared and contrasted to the more often used principal component analysis (PCA). The most significant difference between MF...

Full description

Saved in:
Bibliographic Details
Main Author: L. Lee Grismer
Format: Article
Language:English
Published: Pensoft Publishers 2025-08-01
Series:ZooKeys
Online Access:https://zookeys.pensoft.net/article/159516/download/pdf/
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1849236537299959808
author L. Lee Grismer
author_facet L. Lee Grismer
author_sort L. Lee Grismer
collection DOAJ
description Multiple factor analysis (MFA) is introduced as a diagnostic tool for taxonomy and discussed using examples from the herpetological literature. Its methodology and output are compared and contrasted to the more often used principal component analysis (PCA). The most significant difference between MFA and PCA is that the former can more appropriately integrate numeric (meristic and/or morphometric) and categorical characters (e.g., big-small, blue-red, striped-banded, keeled-smooth, etc.) in the analysis, thus creating a nearly total-evidence morphological output. MFA emphasizes the diagnostic utility of categorical characters in a statistically defensible landscape as opposed to their often-anecdotal treatment or complete omission in species diagnoses, usually owing to their variability. PCA is most informative when only a single numeric data type (e.g., morphometric or meristic) is analyzed. Using PCA to analyze different data types separately and comparing the results, one can determine which data type and which of their variables (traits/characters) bear most heavily on the differentiation among the operational taxonomic units (OTUs [i.e., populations or species]) and, in some cases, their biological significance. If more than one data type is used in a PCA, the output may be biased by the data type with the largest amount of variation or statistical variance. Also discussed is the necessity of using a non-parametric permutation of analysis of variance (PERMANOVA)—or a similar analysis—as a robust, statistically defensible method for assessing the significance of OTU plot positions as opposed to subjective visual interpretations.
format Article
id doaj-art-9a8a99c4b26549c1ad2d1eab87f90db4
institution Kabale University
issn 1313-2970
language English
publishDate 2025-08-01
publisher Pensoft Publishers
record_format Article
series ZooKeys
spelling doaj-art-9a8a99c4b26549c1ad2d1eab87f90db42025-08-20T04:02:13ZengPensoft PublishersZooKeys1313-29702025-08-0112489310910.3897/zookeys.1248.159516159516Introducing multiple factor analysis (MFA) as a diagnostic taxonomic tool complementing principal component analysis (PCA)L. Lee Grismer0San Diego Natural History MuseumMultiple factor analysis (MFA) is introduced as a diagnostic tool for taxonomy and discussed using examples from the herpetological literature. Its methodology and output are compared and contrasted to the more often used principal component analysis (PCA). The most significant difference between MFA and PCA is that the former can more appropriately integrate numeric (meristic and/or morphometric) and categorical characters (e.g., big-small, blue-red, striped-banded, keeled-smooth, etc.) in the analysis, thus creating a nearly total-evidence morphological output. MFA emphasizes the diagnostic utility of categorical characters in a statistically defensible landscape as opposed to their often-anecdotal treatment or complete omission in species diagnoses, usually owing to their variability. PCA is most informative when only a single numeric data type (e.g., morphometric or meristic) is analyzed. Using PCA to analyze different data types separately and comparing the results, one can determine which data type and which of their variables (traits/characters) bear most heavily on the differentiation among the operational taxonomic units (OTUs [i.e., populations or species]) and, in some cases, their biological significance. If more than one data type is used in a PCA, the output may be biased by the data type with the largest amount of variation or statistical variance. Also discussed is the necessity of using a non-parametric permutation of analysis of variance (PERMANOVA)—or a similar analysis—as a robust, statistically defensible method for assessing the significance of OTU plot positions as opposed to subjective visual interpretations.https://zookeys.pensoft.net/article/159516/download/pdf/
spellingShingle L. Lee Grismer
Introducing multiple factor analysis (MFA) as a diagnostic taxonomic tool complementing principal component analysis (PCA)
ZooKeys
title Introducing multiple factor analysis (MFA) as a diagnostic taxonomic tool complementing principal component analysis (PCA)
title_full Introducing multiple factor analysis (MFA) as a diagnostic taxonomic tool complementing principal component analysis (PCA)
title_fullStr Introducing multiple factor analysis (MFA) as a diagnostic taxonomic tool complementing principal component analysis (PCA)
title_full_unstemmed Introducing multiple factor analysis (MFA) as a diagnostic taxonomic tool complementing principal component analysis (PCA)
title_short Introducing multiple factor analysis (MFA) as a diagnostic taxonomic tool complementing principal component analysis (PCA)
title_sort introducing multiple factor analysis mfa as a diagnostic taxonomic tool complementing principal component analysis pca
url https://zookeys.pensoft.net/article/159516/download/pdf/
work_keys_str_mv AT lleegrismer introducingmultiplefactoranalysismfaasadiagnostictaxonomictoolcomplementingprincipalcomponentanalysispca