Plot: Ternary

Selecting the Plot: Ternary tab in the Graph Options dialog box is one way to access the options described here. Use these options to select and further refine the type and various display characteristics of ternary graphs. You can also review the documentation for mixture designs and triangular surfaces in the context of Experimental Design, to learn more about the nature of ternary plots.

Plot

Use the Plot drop-down box to select the plot to which you want to make changes. If you have several plots in one graph, you assign names to each plot using the Name field on the Plot: General tab of the Graph Options dialog box.

Data range

Use the Data range group box to specify the data range for the ternary plot.

Plot Pseudo-components

Select the Plot Pseudo-components check box to recode the component settings to so-called pseudo-components so that (see also Cornell, 1990a, Chapter 3):

x'i = (xi -Li )/(Total-L)

Here, x'i stands for the i'th pseudo-component, xi stands for the original component value, Li stands for the lower constraint (limit) for the i'th component, L stands for the sum of all lower constraints (limits) for all components in the design, and Total stands for the mixture total. This transformation makes the coefficients for different factors comparable in size. When you select this option, the Ignore cases with invalid sums option will automatically be selected (see below).

Ignore cases with invalid sums

Use the Ignore cases with invalid sums check box to manage cases in which the component proportions do not add to the constrained value. If you select this check box, STATISTICA will ignore cases in which the proportions add to a specified expected sum. If you clear this check box, then STATISTICA will rescale the proportions so that they add to 1 in each case.

Expected sum of x+y+z

Use the Expected sum of x+y+z field to specify the sum to which the proportions should add. Note this option is only available if the Ignore cases with invalid sums check box has been selected.

Type

Use the Type drop-down box to select the type of ternary plot: Regular or Selected points.

Regular

Select Regular to display the standard ternary plot.

Selected points

Select Selected points to create subsets of points that will be identified by different point markers in the plot. The method of creating the subsets, i.e., of categorizing the respective variable, can be specified in the Intervals group; these methods are also described in the Methods of Categorization topic.

Intervals

Use the options in the Intervals group to select a method (Integer mode, Unique values, Categories, Boundaries, Codes, or Multiple subsets) for categorizing the points in the plot; the points belonging to different categories (subsets) will be identified by different point markers. Refer to the Methods of Categorization topic for details on the different methods for creating categories.

Change Variable/Specify Boundaries/Specify Codes/Specify Subsets

Note that the name of this button changes depending on the Interval option button that is selected. Click the Change Variable button to display a standard variable selection dialog, which is used to change the selection of the grouping variable to which the Intervals options apply. Click the Specify Boundaries/Codes/Subsets button to display various dialogs in which you enter the boundaries, codes, or subsets that are used to create user-defined categories.

Intervals value format

If the selected Type is Selected points, then the Intervals value format button controls the display of legends defining the categories used in the plot. Click this button to display the Value Format dialog box, from which you can choose the desired format for display of subsets defined by categorization.