The statistical-analysis of somatotype data

Authors

Noel A. Cressie, University of WollongongFollow
Ryan Withers, University Of Newcastle
N Craig

RIS ID

73471

Publication Details

Cressie, N. A., Withers, R. & Craig, N. (1986). The statistical-analysis of somatotype data. Yearbook Of Physical Anthropology, 29 (Supplement - S7), 197-208.

Abstract

The literature contains examples of one-way ANOVAs being conducted on SAD (somatotype altitudinal distance) values to determine whether there are statistically significant differences between group somatotype means. The problems with this strategy concern the premature collapsing of the three component somatotype vectors into a scalar SAD value together with use of the inappropriate degrees of freedom for the F-ratio. A theoretical rationale is presented for remedying the latter defect. However, a one-way MANOVA, which uses Wilks's lambda as the test statistic, is the most powerful method of determining whether there are statistically significant differences between the somatotype means for two or more groups. If the null hypothesis is rejected, then for more than two groups, pairwise comparisons should be conducted by using Hotelling's T2 with a Bonferroni adjusted alpha level. The one-by-one and joint contributions of the somatotype components to each significant pairwise difference can furthermore be determined by univariate F-ratios, discriminant function analyses, and forward stepwise discriminant analyses.