chemometrics (version 1.4.4)

ilr: isometric logratio transformation

Description

A data transformation according to the isometric logratio transformation is done.

Usage

ilr(X)

Value

Returns the transformed data matrix with one dimension less than X.

Arguments

X

numeric data frame or matrix

Author

Peter Filzmoser <[e-mail]>

Details

The ilr transformation is one possibility to transform compositional data to a real space. Afterwards, the transformed data can be analyzed in the usual way.

References

K. Varmuza and P. Filzmoser: Introduction to Multivariate Statistical Analysis in Chemometrics. CRC Press, Boca Raton, FL, 2009.

See Also

alr,clr

Examples

data(glass)
glass_ilr <- ilr(glass)