Principal Component Objects
- DESCRIPTION:
-
The class of objects that results from performing a principal component
analysis.
- GENERATION:
-
This class of objects is returned from princomp.
- METHODS:
-
The class "princomp" has methods for the following generic functions:
biplot, predict, print, rotate, screeplot, summary.
- STRUCTURE:
-
The "princomp" object is implemented as a list
with the following components:
- sdev:
-
vector of standard deviations of the principal components.
- loadings:
-
orthogonal matrix of class "loadings" giving the loadings.
The first column is the linear combination of columns of x defining
the first principal component, etc.
If argument scores was numeric, then this contains that number of columns.
- n.obs:
-
the number of observations on which the estimates are based.
This may not be present if covlist was used.
- scores:
-
the scores of some or all of the principal components for the observations.
- center:
-
vector of centers for the variables.
- scale:
-
vector of numbers by which the variables are scaled.
These are all 1 if cor is FALSE.
If cor is TRUE, then scales will be the square roots of the diagonal
of the cov component of covlist, if present, and otherwise it is the
standard deviations of the input data variables.
- terms:
-
the terms object of the formula.
This is not present if a formula was not used.
- call:
-
an image of the call to princomp.
- SEE ALSO:
-
princomp
,
loadings
.