Analysis of a Screening Experiment with Two-Level Factors

Click the OK button in the Design & Analysis of Screening Experiments dialog box to display the Analysis of a Screening Experiment with Two-Level Factors dialog box (if you have chosen to analyze a design via the Analyze design tab). This dialog box contains nine tabs: Quick, Model, Design, ANOVA/Effects, Means, Review/save residuals, Residual plots, Box-Cox, and Prediction & profiling. The options described below are available regardless of which tab you have selected. See also, the Note on unbalanced designs and singular effects matrices.

Summary box

The Summary box at the top of the dialog box displays a summary of the design including the number of factors, runs, and replications.  

Copy button Click the Copy button to copy either the selected text (if text has been selected) in the Summary box or all of the text (if no text has been selected) to the Clipboard. Note that the copied text retains formatting information (such as font, color, etc.).

Contract/Expand button Click the Contract/Expand button to contract or expand the Summary box. When contracted, you can see only one line of the Summary box text and can scroll through the text using a scroll bar. Note that when contracted the text is scrolled so that the first non-blank line is at the top. When expanded (the default setting), the entire Summary box will be displayed in the Results dialog box.

Variable

If multiple dependent variables are specified for the analysis, use the Variable box to select the dependent variable for which to review the results. Note that you can quickly print to a report the most important results for all variables: 1) select the All variables check box next to the Print results button, and 2) click the Print results button. See also the note on Missing Data and Multiple Dependent Variables.

Print Results

Click the Print results button to compute the main effects and interactions estimates (see Main Effects and Interactions), the regression coefficients, and the ANOVA table for the current variable and send them to a report. See the ANOVA/Effects tab for more details on these options. Note that if you don't have a Send to report option selected in the Output Manager, you will be prompted to select that option here. To send the results to a printer, see Printing a Report.  

All variables

Select the All variables check box to send the results for all dependent variables in the current analysis to a report when you click the Print results button.

Summary

Click the Summary button to produce a spreadsheet with the ANOVA effect estimates and coefficients for the coded model. The effects that will be computed depend on the current model, as specified via the options in the Include in model group box on the Model tab. Additional options for confidence intervals, Alpha highlighting, and sorting effects are available on the ANOVA/Effects tab. All estimates in this spreadsheet pertain to the coded factor settings, that is, to the factor settings scaled to the ±1 range. To see the results for the original (untransformed) factor settings, use the Regression coefficients option on the ANOVA/Effects tab. For a description of the statistics contained in this spreadsheet, see Main Effects and Interactions for Screening (Plackett-Burman) Experiments.

Cancel

Click the Cancel button to return to the Design & Analysis of Screening Experiments dialog box.  

Options

Click the Options button to display the Options menu.

Note: screening experiments can also be analyzed via General Linear Models (GLM) or General Regression Models (GRM), or via the (nonlinear) Generalized Linear Models (GLZ) module.