Workspace Node: Principal Components and Classification Analysis - Results - Quick Tab

In the Principal Components and Classification Analysis node dialog box, under the Results heading, select the Quick tab to access the following options.

Element Name Description
Number of factors Enter the number of factors to be computed in the Principal Components Analysis and displayed in the spreadsheets in the Number of factors field. You can change this number at any stage of the analysis.
Note: Quality of representation. For each selected number in the Number of factors field, the percent of total variance explained by the respective number of factors will be displayed as the quality of representation. Note that the Quality of representation field works in conjunction with the Number of factors field: the value displayed in this field is recalculated whenever the number in the Number of factors field is changed. By default this field shows 100% quality of representation corresponding to the maximum number of factors shown in the Number of factors field (see above).
Factor coordinates of variables Select this check box to produce a spreadsheet with the factor coordinates of the active and supplementary variables (if selected via the Variables button of the Specifications - Quick tab). To distinguish between the two types of variables in the current analysis, the supplementary variables are marked with an asterisk (*). The factor coordinates are commonly referred to as factor loadings, and provide useful information for the interpretation of the factors. Refer to the Introductory Overview for additional details.
Factor coordinates of cases Select this check box to produce a spreadsheet with factor coordinates of cases. The spreadsheet will also contain:
  1. an additional column displaying the code for active and supplementary cases, if a Variable for active cases was selected via the Variables button on the Specifications - Quick tab;
  2. an additional column (last), displaying the label defined by the grouping variable, if a Grouping variable was selected via the Variables button on the Specifications - Quick tab.
Note: the spreadsheet will display the factor coordinates only for the complete (valid) cases if the Casewise option button was selected in the MD deletion group box on Specifications - Quick tab. Alternatively, if Mean substitution was selected, the mean of the corresponding variable will be used in place of missing data and the spreadsheet will contain the factor coordinates for all cases. The Number of factors selected for the current analysis will determine the number of factors for which the coordinates will be computed and displayed. Note that the estimates of means and standard deviations that are used in the computation of factor coordinates of cases are computed from all valid cases, both active and supplementary. Refer to the Introductory Overview for additional details.
Eigenvalues Select this check box to produce a spreadsheet with the positive eigenvalues of the correlation or covariance matrix (depending on which was chosen for the analysis in the Analysis based on group box on the Specifications - Quick tab). Note that the displayed eigenvalues are computed from the correlations or covariances of the active variables only, even if supplementary variables were selected via the Variables button on the Specifications - Quick tab.
Plot var. factor coordinates, 2D Select this check box to produce a 2D scatterplot of the current set of factor coordinates for the selected pair of factors. After you select this check box, click the adjacent button to display the Select Two Factors for the Plot dialog box, where you can select factors for the factor axes. Subsequent to clicking this button, you can use one of the Options for plot of factor coord. on the Results - Variables tab.
Plot case factor coordinates, 2D Select this check box to produce a 2D scatterplot of the factor coordinates for the cases. The plot will contain coordinates for the supplementary cases, provided a Variable for active cases was selected and a valid Code for active cases was chosen on the Specifications - Quick tab. After you select this check box, click the adjacent button to display the Select Two Factors for the Plot dialog box, where you can select factors for the factor axes. Subsequent to clicking this button, you can use one of the Options for plot of factor coord. on the Results - Cases tab.
Scree plot Select this check box to produce a simple line plot of the eigenvalues, called a Scree plot (Cattell, 1966). The eigenvalues in this plot appear to level off at certain point.  It is recommended that no more than the number of factors to the left of this point should be computed. Note that the scree plot will plot all the eigenvalues of the correlation or covariance matrix, irrespective of the Numbers of factors chosen for the current analysis.

Options / C. See Common Options.

OK Click the OK button to accept all the specifications made in the dialog box and to close it. The analysis results will be placed in the Reporting Documents node after running (updating) the project.