princomp.rmult {compositions}R Documentation

Principle component analysis for Real data

Description

Performes a principle component analysis for datasets of type rmult.

Usage

## S3 method for class 'rmult':
princomp(x,...)

Arguments

x a rmult-dataset
... Further arguments to call of princomp.default

Details

The function just does princomp(unclass(x),...,scale=scale) and is only here for convenience.

Value

An object of type princomp with the following fields

sdev the standard deviation of the principle components.
loadings the matrix of variable loadings (i.e., a matrix whose columns contain the eigenvectors). This is of class "loadings". The last eigenspace is removed since it should contain the irrelevant scaling.
center the clr of the means that was substracted
scale the scaling applied to each variable
n.obs number of observations
scores if scores = TRUE, the scores of the supplied data on the principle components and the information was available. Scores are coordinates in a basis given by the principle components and thus not compositions.
call the matched call
na.action Not clearly understood

Author(s)

K.Gerald v.d. Boogaart http://www.stat.boogaart.de

See Also

princomp.rplus

Examples

data(SimulatedAmounts)
pc <- princomp(rmult(sa.lognormals5))
pc
summary(pc)
plot(pc) 
screeplot(pc)
screeplot(pc,type="l")
biplot(pc)
biplot(pc,choice=c(1,3))
loadings(pc)
plot(loadings(pc))
pc$sdev^2
cov(predict(pc,sa.lognormals5))

[Package compositions version 0.9-11 Index]