CORRESPONDENCE-ANALYSIS AS A TOOL IN FUNGAL TAXONOMY

Citation
Tn. Sieber et al., CORRESPONDENCE-ANALYSIS AS A TOOL IN FUNGAL TAXONOMY, Systematic and applied microbiology, 21(3), 1998, pp. 433-441
Citations number
23
Categorie Soggetti
Microbiology,"Biothechnology & Applied Migrobiology
ISSN journal
07232020
Volume
21
Issue
3
Year of publication
1998
Pages
433 - 441
Database
ISI
SICI code
0723-2020(1998)21:3<433:CAATIF>2.0.ZU;2-S
Abstract
The polyphasic approach to taxonomic problems has led to the creation of complex datasets that lend themselves to numerical analysis. The nu merical study, however, has to deal with mathematical problems linked with the presence of mixed-type data originating from the investigatio ns. Correspondence analysis (CA) is an ordination technique widely use d in ecology and social sciences but only rarely applied to taxonomic problems. In Cb corresponding variables and taxa ordination are obtain ed simultaneously, thus allowing to explore the taxonomic interrelatio nships between taxa and variables in a single analysis. CA can be used on large and small datasets, and can be applied to mixed-type data af ter appropriate coding. It is not sensitive to variation of class numb er and size and is useful to screen large unstructured datasets, to su ggest which variables should be retained to discriminate samples, to d etect outliers or erroneous data and to perform identification of unkn own samples. It also has the advantage of handling missing data partic ularly well. On the other hand, CA is sensitive to outliers, which can cause a distortion of the geometric map of the points in the graphica l display. Nevertheless, the sensitivity of correspondence analysis to outliers can be effectively used to verify data. Finally, based on sy mmetry of row and column analyses correspondence analysis can be appli ed to find out which characters can be used to construct identificatio n keys and to selectively group variables by their importance for the discrimination of samples.