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

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

Element Name Description
Summary descriptives Select this check box to produce a spreadsheet with the descriptive statistics, means and standard deviations, for the variables in the current analysis.
Correlation matrix Select this check box to produce a spreadsheet with the correlation matrix for all variables (active as well as supplementary). Note that the correlation matrix can be produced irrespective of whether the analysis was based on correlations. However, if the Correlations option button was selected in the Analysis based on group box on the Specifications - Quick tab, this is the matrix that has been used for computing the principal components and the related statistics.
Inverse correlation Select this check box to produce the inverse of the correlation matrix for the active variables only.
Covariance matrix Select this check box to produce a spreadsheet with the covariance matrix for all variables (active as well as supplementary). Note that the covariance matrix can be produced irrespective of whether the analysis was based on covariances. However, if the Covariances option button was selected in the Analysis based on group box on the Specifications - Quick tab, this is the matrix that has been used for computing principal components and the related statistics.
Inverse covariance Select this check box to produce the inverse of the covariance matrix.
Include in plots If a Variable for active cases was selected (via the Variables button on the Specifications - Quick tab), the code for active cases will categorize the cases into active and supplementary cases. You can then use the options in the Include in plots group box to choose to produce various plots (described below) either for the active cases only, the supplementary cases only, or for all cases.
All cases Select this option button to include both active and supplementary cases in the plots described below.
Active cases only Select this option button to include only the active cases in the plots described below.
Supplementary cases only Select this option button to include only the supplementary cases in the plots described below.
Box-Whisker Type Select one of the box-whisker types (described below) to use in combination with the Box and whisker plot by group option (described below).
Median/Quart./Range This box plot describes the central tendency of the variable in terms of the median of the values (represented by the smallest box in the plot). The spread (variability) in the variable values is represented in this plot by the quartiles (the 25th and 75th percentiles, larger box in the plot) and the minimum and maximum values of the variable (the "whiskers" in the plot).
Mean/SE/SD Here, the smallest box in the plot represents the mean (central tendency) of the variable, while the dispersion (variability) is represented by ± 1 times the standard error (large box) and ± 1 times the standard deviation about the mean ("whiskers").
Mean/SD/1.96*SD This plot will show the mean (small box in the plot) of the variable surrounded by a larger box (± 1 times the standard deviation). If the distribution is normal, the "whiskers" in this plot represent a "95% confidence interval" defined as the variable mean ± 1.96 times the variable standard deviation.
Mean/SE/1.96*SE This plot will show the mean (small box in the plot) of the variable surrounded by a larger box. However, in this plot, the larger box represents ± 1 times the standard error. If the distribution is normal, the "whiskers" in this plot represent a "95% confidence interval" defined as the variable mean ± 1.96 times the variable standard deviation.
Box & whisker plot by group Select this check box to produce a box & whisker plot. Click the adjacent button to display a standard variable selection dialog box, where you can select the variables for which you would like to produce the plot. Use the options in the Box-Whisker Type group box, described above, to specify the type of box & whisker plot to be produced. By selecting the appropriate option button in the Include in plots group box (see above), you can choose to include All cases, Active cases only, or Supplementary cases only in the box & whisker plot.
2D scatterplots Select this check box to produce a 2D scatterplot. Click the adjacent button to display a standard variable selection dialog box, where you can select a pair of variables for the x- and y-axis. By selecting the appropriate option button in the Include in plots group box (see above), you can choose to include All cases, Active cases only, or Supplementary cases only in the 2D scatterplot.
Histograms Select this check box to produce a cascade of histograms for the variables in the current analysis. By selecting the appropriate option button in the Include in plots group box (see above), you can choose to include All cases, Active cases only, or Supplementary cases only in the histogram.
3D scatterplots Select this check box to produce a 3D scatterplot. Click the adjacent button to display a standard variable selection dialog box, where you can select a triplet of variables for the x-, y-, and z-axis. By selecting the appropriate option button in the Include in plots group box (see above), you can choose to include All cases, Active cases only, or Supplementary cases only in the 3D scatterplot.
Normal prob. plots Select this check box to produce a cascade of normal probability plots for the variables in the current analysis. For more information on how the standard normal probability plot is constructed, see the Factor Analysis topic Computation note for normal probability plots. By selecting the appropriate option button in the Include in plots group box (see above), you can choose to include All cases, Active cases only, or Supplementary cases only in the normal probability plot.
Surface plots Select this check box to produce a surface plot. Click the adjacent button to display a standard variable selection dialog box, where you can select a triplet of variables for the x-, y-, and z-axis. By selecting the appropriate option button in the Include in plots group box (see above), you can choose to include All cases, Active cases only, or Supplementary cases only in the surface plot. Note that if the surface fit to the plotted data cannot be computed, only a 3D scatterplot will be produced.

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.