Exploratory compositional data analysis using the R-package robCompositions

Abstract

Compositional data are multivariate observations that carry only relative information. This means that not the absolute values but the ratios between the variables are of interest. This is important also for an exploratory analysis of such data. We present two basic methods for the exploratory compositional data analysis (ECDA), namely multivariate outlier detection and the compositional biplot. The methods are illustrated at a small data example using the R package robCompositions.