R: Extract cluster definitions from factor loadings

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)

http://personality-project.org/revelle.html

Maintainer: William Revelle revelle@northwestern.edu

### References

http://personality-project.org/r/r.vss.html

### See Also

`cluster.cor`, `factor2cluster`, `fa`, `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 1.7.8 Index]