EFA.dimensions (version 0.1.8.1)

PCA: Principal components analysis

Description

Principal components analysis

Usage

PCA(data, corkind='pearson', Nfactors=NULL, Ncases=NULL, rotation='promax', 
	 ppower=3, verbose=TRUE, rotate)

Value

A list with the following elements:

loadingsNOROT

The unrotated factor loadings

loadingsROT

The rotated factor loadings

pattern

The pattern matrix

structure

The structure matrix

phi

The correlations between the factors

varexplNOROT1

The initial eigenvalues and total variance explained

varexplROT

The rotation sums of squared loadings and total variance explained for the rotated loadings

cormat_reprod

The reproduced correlation matrix, based on the rotated loadings

fit_coeffs

Model fit coefficients

communalities

The unrotated factor solution communalities

uniquenesses

The unrotated factor solution uniquenesses

Arguments

data

An all-numeric dataframe where the rows are cases & the columns are the variables, or a correlation matrix with ones on the diagonal.The function internally determines whether the data are a correlation matrix.

corkind

The kind of correlation matrix to be used if data is not a correlation matrix. The options are 'pearson', 'kendall', 'spearman', 'gamma', and 'polychoric'. Required only if the entered data is not a correlation matrix.

Nfactors

The number of components to extraction. If not specified, then the EMPKC procedure will be used to determine the number of components.

Ncases

The number of cases. Required only if data is a correlation matrix.

rotation

The factor rotation method for the analysis. The orthogonal rotation options are: 'varimax' (the default), 'quartimax', 'bentlerT', 'equamax', 'geominT', 'bifactorT', 'entropy', and 'none'. The oblique rotation options are: 'promax' (the default), 'quartimin', 'oblimin', 'oblimax', 'simplimax', 'bentlerQ', 'geominQ', 'bifactorQ', and 'none'.

ppower

The power value to be used in a promax rotation (required only if rotation = 'promax'). Suggested value: 3

verbose

Should detailed results be displayed in console? TRUE (default) or FALSE

rotate

(Deprecated.) Use 'rotation' instead.

Author

Brian P. O'Connor

Examples

# \donttest{
# the Harman (1967) correlation matrix
PCA(data_Harman, Nfactors=2, Ncases=305, rotation='oblimin', verbose=TRUE)

# Rosenberg Self-Esteem scale items
PCA(data_RSE, corkind='polychoric', Nfactors=2, rotation='bifactorQ', verbose=TRUE)

# NEO-PI-R scales
PCA(data_NEOPIR, corkind='pearson', Nfactors=5, rotation='promax', ppower = 4, verbose=TRUE)
# }