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Compositional (version 5.5)

The Box-Cox transformation applied to ratios of components: The Box-Cox transformation applied to ratios of components

Description

The Box-Cox transformation applied to ratios of components.

Usage

bc(x, lambda)

Arguments

x

A matrix with the compositional data. The first component must be zero values free.

lambda

The value of the power transformation, it has to be between -1 and 1. If zero values are present it has to be greater than 0. If \(\lambda=0\) the additive log-ratio transformation (alr) is applied.

Value

A matrix with the transformed data.

Details

The Box-Cox transformation applied to ratios of components, as described in Aitchison (1986) is applied.

References

Aitchison J. (1986). The statistical analysis of compositional data. Chapman & Hall.

See Also

alr, fp, green, alfa

Examples

Run this code
# NOT RUN {
library(MASS)
x <- as.matrix(fgl[, 2:9])
x <- x / rowSums(x)
y1 <- bc(x, 0.2)
y2 <- bc(x, 0)
rbind( colMeans(y1), colMeans(y2) )
rowSums(y1)
rowSums(y2)
# }

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