This topic applies to mixture designs.
Modify the component names and the process variable names and the process variable low and high values. Usually, you modify process variables because you did not specify levels for the variables during design creation. The default levels are set so that the low level is −1 and the high level is 1. For a correct analysis when you analyze the experiment, you must use Modify Design instead of typing the levels directly in the worksheet. For individual runs that have settings that differ from the planned settings, type changes in the worksheet.
For example, an engineer creates a mixture design to study the effects of metal components on tensile strength. During the design creation in Minitab, the engineer did not specify the component names, the process variable names, or the process variable levels. Thus, the components are specified as A, B, C, the process variable is specified as X1, and the process variable levels are coded so that the low level is −1 and the high level is 1. Before collecting the data, the engineer wants to specify the component names, the process variable names, and the process variable levels so that the settings are more meaningful.
If you specified process variable levels when you created the design, you can use Display Design to change between coded and uncoded process variable levels.