Multidimensional Unfolding Plots

The Plots dialog box allows you to specify which plots will be produced.

Plots. The following plots are available:

  • Multiple starts. Displays a stacked histogram of penalized stress displaying both stress and penalty.
  • Initial common space. Displays a scatterplot matrix of the coordinates of the initial common space.
  • Stress per dimension. Produces a lineplot of penalized stress versus dimensionality. This plot is produced only if the maximum number of dimensions is larger than the minimum number of dimensions.
  • Final common space. A scatterplot matrix of coordinates of the common space is displayed.
  • Space weights. A scatterplot is produced of the individual space weights. This is possible only if one of the individual differences models is specified in the Model dialog box. For the weighted Euclidean model, the weights for all sources are displayed in a plot, with one dimension on each axis. For the generalized Euclidean model, one plot is produced per dimension, indicating both rotation and weighting of that dimension for each source.
  • Individual spaces. A scatterplot matrix of coordinates of the individual space of each source is displayed. This is possible only if one of the individual differences models is specified in the Model dialog box.
  • Transformation plots. A scatterplot is produced of the original proximities versus the transformed proximities. Depending on how transformations are applied, a separate color is assigned to each row or source. An unconditional transformation produces a single color.
  • Shepard plots. The original proximities versus both transformed proximities and distances. The distances are indicated by points, and the transformed proximities are indicated by a line. Depending on how transformations are applied, a separate line is produced for each row or source. An unconditional transformation produces one line.
  • Scatterplot of fit. A scatterplot of the transformed proximities versus the distances is displayed. A separate color is assigned to each source if multiple sources are specified.
  • Residuals plots. A scatterplot of the transformed proximities versus the residuals (transformed proximities minus distances) is displayed. A separate color is assigned to each source if multiple sources are specified.

Row Object Styles. These give you further control of the display of row objects in plots. The values of the optional colors variable are used to cycle through all colors. The values of the optional markers variable are used to cycle through all possible markers.

Source Plots. For Individual spaces, Scatterplot of fit, and Residuals plots—and if transformations are applied by source, for Transformation plots and Shepard plots—you can specify the sources for which the plots should be produced. The source numbers entered must be values of the sources variable specified in the main dialog box and range from 1 to the number of sources.

Row Plots. If transformations are applied by row, for Transformation plots and Shepard plots, you can specify the row for which the plots should be produced. The row numbers entered must range from 1 to the number of rows.

To Obtain Plots in Multidimensional Unfolding

This feature requires the Categories option.

  1. From the menus choose:

    Analyze > Scale > Multidimensional Unfolding (PREFSCAL)...

  2. In the Multidimensional Unfolding dialog box, click Plots.