A data transformation according to the additive logratio transformation is done.
Usage
alr(X, divisorvar)
Value
Returns the transformed data matrix with one variable (divisor variable) less.
Arguments
X
numeric data frame or matrix
divisorvar
number of the column of X for the variable to divide with
Author
Peter Filzmoser <P.Filzmoser@tuwien.ac.at>
Details
The alr 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.