Optimal Design Result: Response Surface - Quick Tab

Select the Quick tab of the Optimal Design Result: Response Surface dialog box to access the options described here.

Display design

Click the Display design button to produce a spreadsheet containing the selected points. The way in which these points are displayed is affected by the selection of 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.

The second column of the spreadsheet contains the prediction variances. For design point i, this value is computed as (see Mitchell, 1974b):

si2 = f(xi)'*(X'X)-1*f(xi)

where X stands for the design matrix, and f(xi) is the vector of codes associated with the factor effects in the current model for design point i.

Order of runs

The choice of options in the Order of runs group box affects the order of runs displayed in the spreadsheet (via option Display design, see above).

Standard order

Select the Standard order option button to display the design in standard order (the order in which it appears in the candidate list).

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 fluctuations in the production process across runs.

Summary: Efficiency measures

Click the Summary: Efficiency measures button to produce a spreadsheet containing the summary of efficiency measures. For a description of these efficiency measures, see Efficiency Measures for D- and A-Optimal Designs. Note that the D- and A- efficiency measures are only reported if the current model is a response surface (and not a mixture) model, and when the factors are recoded to the ±1 range (see the D- and A-Optimal Designs - Options tab). For a discussion of the different optimality criteria, refer to the Introductory Overview.

2D Scatterplot of points

Click the 2D Scatterplot of points button to display a scatterplot of the final design points for two factors. If there are more than two factors in the current design,after clicking the 2D Scatterplot of points button, the Select factors for 2D scatterplot dialog box will be displayed. In this dialog box, select the two factors for the 3D scatterplot.

3D Scatterplot of points

Click the 3D Scatterplot of points button to produce a 3D scatterplot of the design points. If there are more than three factors in the current design,after clicking the 3D Scatterplot of points button, the Select factors for 3D Scatterplot dialog box will be displayed. In this dialog box, select the three factors for the 3D scatterplot.