This is what it does.

Compositional Statistics Calculator Description

This calculator performs computations described in *A Concise Guide to Compositional Data Analysis *by John Aitchison.

First, it transforms raw data (x_{1}, x_{2}, x_{3},…) into a *composition* (X_{1}, X_{2}, X_{3},…), whose value sum to 1, or 100%. It would also *normalize* a raw composition (x_{1}, x_{2}, x_{3},…) into a unit-sum constrained composition (X_{1}, X_{2}, X_{3},…).

It then performs a logratio transformation of the composition followed by computation of distributional variation as three matrix specifications:

- logratio covariance matrix,
- centered logratio covariance matrix, and
- variation matrix.

Finally, it computes measures of central tendency using two algorithms which produce identical results:

- logratio mean vector, and
- centered logratio mean vector.