Design of an Experiment with Three-Level Factors - Add to Design Tab

Designing 3(k-p) Experiments

Select the Add to design tab of the Design of an Experiment with Three-Level Factors dialog to access the options described here.

Add to the design

Use the options in the Add to the design group box to add points or columns to the standard design. Note that the settings in this group box only affect the displayed design (via option Summary: Display design on the Quick tab or Display design tab). The changes do not affect the results displayed in the Correlation matrix (main effects and interactions) spreadsheet [via option Correlation matrix (main effects and interactions) on the Generators and Aliases tab]. Those correlations always pertain to the standard design. The changes also do not affect the information displayed in the Summary box.

Number of genuine replicates

Enter a number in the Number of genuine replicates box (or adjust the number using the microscrolls) to replicate the complete design the respective number of times. For example, if you enter a 1 into the box, then Statistica adds one replicate to the design, resulting in two identical parts of the design. If you want to replicate selected points from the design (e.g., so that you can later obtain an estimate of pure error; see Replicating the Design), first display the design (via the Summary: Display design option on the Quick tab or Display design tab), add rows to the spreadsheet (use option Insert - Add Cases), and then copy and paste the respective runs into those new rows.

Number of center points (per block)

Enter a number in the Number of center points (per block) box (or adjust the number using the microscrolls) to add center points to the design. For center point runs, all factors will be set at their center value. To maintain a balanced and orthogonal design, if there is blocking in the current design, then Statistica will add the same number of center points to each block in the design.

Number of blank columns (dep. vars).

Enter a number in the Number of blank columns (dep. vars) box (or adjust the number using the microscrolls) to add the respective number of blank columns to the displayed design (via the Summary: Display design option on the Quick tab or Display design tab). This option is useful if you want to print the spreadsheet with the extra columns to use as a convenient data entry form.