The Method Tab

You can use the Method tab (Figure 27.4) to set options in the analysis.

Each of the following options corresponds to an option in the FACTOR procedure.

Factoring method

specifies the method used to extract factors or specifies a component analysis. This corresponds to the METHOD= option in the PROC FACTOR statement.

Compute factors from

specifies whether the factors are computed for the correlation matrix or the covariance matrix. This corresponds to the COV option in the PROC PRINCOMP statement. Note: Some methods require a correlation matrix.

Number of Factors

The number of factors retained is determined by the minimum number satisfying the next three criteria.

Maximum number

specifies how many factors to compute. This corresponds to the N= option in the PROC FACTOR statement. Note that you can type into the field; if you want five factors, you can enter 5 even though this is not an option on the list.

Proportion of variance

specifies the proportion of common variance in the retained factors. This value is in the range . The option corresponds to the PROPORTION= option in the PROC FACTOR statement.

Minimum eigenvalue

specifies the smallest eigenvalue for which a factor is retained. This corresponds to the MINEIGEN= option in the PROC FACTOR statement.

Prior estimates

specifies a method for computing prior communality estimates. This corresponds to the PRIORS= option in the PROC FACTOR statement. Note that the default method for the principal factor method is to set all priors equal to 1. This results in a principal component analysis. If you want a principal factor analysis, you should select a different method for estimating the prior communalities, as illustrated in the section "Example".

Heywood Conditions

specifies how the factor analysis behaves if a communality is greater than 1. The section "Heywood Cases and Other Anomalies about Communality Estimates" in the documentation for the FACTOR procedure describes why this situation might occur.

Do not allow communalities greater than one

specifies that an analysis should stop processing if it encounters a communality greater than one.

Set any communality greater than one to one

specifies that an analysis should set any communality greater than one to one, and then continue. This corresponds to the HEYWOOD option in the PROC FACTOR statement.

Allow communalities greater than one

specifies that an analysis should allow any communality. This corresponds to the ULTRAHEYWOOD option in the PROC FACTOR statement.