Data - Overlaid Contour Plot
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You must fit a regression model with two or more 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. Overlaid contour plot does not use the data in the worksheet. Instead, Minitab looks in the worksheet for the stored model(s) to obtain the necessary information.

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, click View Model in the Overlaid Contour Plot dialog.