Analysis of an Experiment with Two- and Three-Level Factors - Means Tab

Designs for Factors at 2 and 3 Levels

Select the Means tab of the Analysis of an Experiment with Two- and Three-Level Factors dialog to access options to review and plot various means from the analysis as well as to perform response desirability profiling. Note that these results are for the currently specified model. You can specify a new model on the Model tab.

Observed design and means

Use the options in the Observed design and means group box to display a spreadsheet (described below) and choose whether to display text labels in the spreadsheet.

Display design and observed means

Click the Display design and observed means button to display a spreadsheet showing the unique runs (those with unique combinations of factor settings) in the experiment. In addition, for each unique run STATISTICA will compute the mean, standard deviation, and standard error of the mean (if there is more than one run for the respective unique combination of factor settings).

Show text labels instead of factor values

If the Show text labels instead of factor values check box is selected, the factor settings in the spreadsheet will be identified by their respective text labels. If there are no text labels in the file (for the list of independent variables or factors), then this option will not be available. Note that the setting of this option also determines whether or not text labels will be shown in spreadsheets with marginal means and in marginal means plots.

Observed marginal means

Use the options in the Observed marginal means group box to display or print the marginal means for the current model. Click the Display button or Means plot button to display the Compute marginal means for dialog, in which you specify for which factors to display or print marginal means.

Display

Click the Display button to compute the marginal means for the design (e.g., the means for Factor 1 by Factor 2, collapsed across Factor 3 and Factor 4). If the Show text labels instead of factor values check box is selected (see above), then factor levels in this plot will be labeled with the respective text labels.

Means plot

Click the Means plot button to produce a plot of weighted or unweighted marginal means. If the Show text labels instead of factor values check box is selected (see above), then factor levels in this plot will be labeled with the respective text labels. The computation of the marginal means, standard errors, and confidence intervals follows the procedures outlined in the note on Marginal means. After selecting the factors for the marginal means plot, the Specify the arrangement of the factors in the plot dialog is displayed, in which you select the assignment of factors. Note that the orientation and layout of the x-upper value labels can be adjusted via the Graph Options dialog.

Display/plot weighted means

Select the Display/plot weighted means check box to display or plot weighted marginal means. For more details, see Marginal Means in Experiments with Two- and Three-Level Factors.

Show confidence intervals

Select the Show confidence intervals check box to display or plot confidence intervals. The confidence limits for the marginal means are computed based on the respective estimates of the standard errors. The percentile used for the confidence limits (e.g., 95%, 90%, etc.) depends on the setting in the Confidence interval box on the ANOVA/Effects tab.

Predicted (estimated) means. Use the option in the Predicted (estimated) means group box to access the Profiler dialog.

Response desirability profiling

Click the Response desirability profiling button to display the Profiler dialog. Use the Profiler to inspect the predicted values for the dependent variables at different combinations of levels of the independent variables, to specify desirability functions for the dependent variables, and to specify a search for the levels of the independent variables that produce the most desirable response on the dependent variables.