factor2cluster {psych} R Documentation

Extract cluster definitions from factor loadings

Description

Given a factor or principal components loading matrix, assign each item to a cluster corresponding to the largest (signed) factor loading for that item. Essentially, this is a Very Simple Structure approach to cluster definition that corresponds to what most people actually do: highlight the largest loading for each item and ignore the rest.

Usage

```factor2cluster(loads, cut = 0)
```

Arguments

 `loads` either a matrix of loadings, or the result of a factor analysis/principal components analyis with a loading component `cut` Extract items with absolute loadings > cut

Details

A factor/principal components analysis loading matrix is converted to a cluster (-1,0,1) definition matrix where each item is assigned to one and only one cluster. This is a fast way to extract items that will be unit weighted to form cluster composites. Use this function in combination with cluster.cor to find the corrleations of these composite scores.

A typical use in the SAPA project is to form item composites by clustering or factoring (see `ICLUST`, `principal`), extract the clusters from these results (`factor2cluster`), and then form the composite correlation matrix using `cluster.cor`. The variables in this reduced matrix may then be used in multiple R procedures using mat.regress.

The input may be a matrix of item loadings, or the output from a factor analysis which includes a loadings matrix.

Value

a matrix of -1,0,1 cluster definitions for each item.

Author(s)

Maintainer: William Revelle revelle@northwestern.edu

See Also

`cluster.cor`, `factor2cluster`, `factor.pa`, `principal`, `ICLUST`

Examples

```
## Not run:
f  <- factanal(x,4,covmat=Harman74.cor\$cov)
factor2cluster(f)
## End(Not run)
#                       Factor1 Factor2 Factor3 Factor4
#VisualPerception             0       1       0       0
#Cubes                        0       1       0       0
#PaperFormBoard               0       1       0       0
#Flags                        0       1       0       0
#GeneralInformation           1       0       0       0
#PargraphComprehension        1       0       0       0
#SentenceCompletion           1       0       0       0
#WordClassification           1       0       0       0
#WordMeaning                  1       0       0       0
#Addition                     0       0       1       0
#Code                         0       0       1       0
#CountingDots                 0       0       1       0
#StraightCurvedCapitals       0       0       1       0
#WordRecognition              0       0       0       1
#NumberRecognition            0       0       0       1
#FigureRecognition            0       0       0       1
#ObjectNumber                 0       0       0       1
#NumberFigure                 0       0       0       1
#FigureWord                   0       0       0       1
#Deduction                    0       1       0       0
#NumericalPuzzles             0       0       1       0
#ProblemReasoning             0       1       0       0
#SeriesCompletion             0       1       0       0
#ArithmeticProblems           0       0       1       0

```

[Package psych version 1.0-68 Index]