Datasets collected by high-throughput sequencing (HTS) of 16S rRNA gene amplimers,
metagenomes or metatranscriptomes are commonplace and being used to study human …

Purpose The ability to properly analyze and interpret large microbiome data sets has
lagged behind our ability to acquire such data sets from environmental or clinical samples. …

Geometry in the simplex has been developed in the last 15 years mainly based on the
contributions due to J. Aitchison. The main goal was to develop analytical tools for the statistical …

… in the simplex (Egozcue and Pawlowsky-Glahn, 2001, 2002; Pawlowsky-Glahn and …
useful expressions to compute the total variance (Egozcue and Pawlowsky-Glahn, 2011). …

… Compositions are represented in the plane of two orthogonal coordinates (Egozcue …
associated with a single partition were developed by Egozcue and others (2003). Coordinates of a …

… general equations for any number of parts can be found either in the references cited in
the previous paragraph, or in other contributions to this book, particularly in Egozcue & …

… A similar reasoning lead Aitchison 2001) to justify the closed geometric mean as the natural
center of a random composition and, later, Pawlowsky-Glahn and Egozcue 2001) to define …

In the life sciences, many measurement methods yield only the relative abundances of
different components in a sample. With such relative—or compositional—data, differential …

The main features of the Aitchison geometry of the simplex of D parts are reviewed.
Compositions are positive vectors in which the relevant information is contained in the ratios …

High-throughput sequencing technologies have revolutionized microbiome research by
allowing the relative quantification of microbiome composition and function in different …