Data - Overlaid Contour Plot
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You must fit a factorial design model with at least two continuous variables before you can generate an overlaid contour plot. If you want to include multiple responses, you must fit a model for each response separately. Minitab looks in the worksheet for the stored model(s) to obtain the information necessary to generate the plot.

Minitab automatically stores the most recent model that you fit for each response variable. To view information about models that are stored in the worksheet, go to the View Model subdialog.