Constrained Mixture Design Results - Quick Tab

Analyzing Mixture Experiments

Select the Quick tab of the Constrained Mixture Design Results dialog to access the options described here.

Summary: Display design

Click the Summary: Display design button to display a spreadsheet containing the vertex and centroid points. The way in which these points are displayed is affected by the respective settings of the options on the Display design tab. To save the design, select the spreadsheet and use the Save or Save As options on the File menu. To use this spreadsheet in further analyses, you must specify it as an input spreadsheet. For more information, see the Input Spreadsheet Overview.

Note: Partial replications. If you want to replicate selected points from the design (e.g., so that you can later obtain an estimate of pure error; see the Introductory Overview), first add rows to the design (use option Insert - Add Cases), and then copy and paste the respective runs into those new rows.

Triangular scatterplot

Click the Triangular scatterplot button to display a triangular scatterplot of the constrained experimental region. If there are more than three factors in the current design, after clicking the Triangular scatterplot button, the Select factors for 3D Scatterplot dialog will be displayed. From this dialog, select the three factors for the triangular scatterplot. Note that this scatterplot shows not only points for which the sum of the components is equal to the mixture total, but also "projected" points. If there are only three factors in the design, then the sum of the component values is, of course, always equal to the mixture total. However, if there are more than three variables in the design, then the scatterplot also shows those points where the component values for the components in the plot is not equal to the mixture total (but greater than 0). The values for those points are proportionately adjusted in the plot (maintaining the ratio of the component values) so that they sum to the mixture total.

Order of runs

The choice of options in the Order of runs group box determines how the design is displayed.

Standard order

If you select the Standard order option button, the design is displayed in standard order.

Random

To randomize the order of runs, select the Random option button. For standard experiments, it is common practice to randomize the runs in order to avoid any systematic biases due to, for example, fluctuations in the production process across runs.