A comparison of eight numerical procedures applied to the classification of some African Trifolium taxa based on Rhizobium affinities

Abstract

A comparative study was made of correlation coefficients, taxonomic distance, non-metric coefficient, and probabilistic index in combmatlon with nearest neighbour, furthest neighbour, centroid, and flexible sorting as methods for the classification of 16 Trifolium taxa. The data used were published Rhizobium affinities that were shown to be meaningful from the point of view of morphology, cytology, and evolutionary theory. The criterion used in testing the numerical methods was the ability to produce groups of taxa in accordance with Rhizobium affinity groups.

On the basis of this study acceptable classifications were obtained by using the non-metric coefficient with flexible sorting, taxonomic distance with furthest neighbour, and taxonomic distance with flexible sorting.