Specify the options for Expanded Gage R&R Study

Stat > Quality Tools > Gage Study > Gage R&R Study (Expanded) > Options
Study variation
Enter a constant to multiply by the standard deviation to estimate the variation in the measurements. The default multiplier is 6, which is the number of standard deviations that is needed to include 99.73% of your measurements.
Note

If you provide only one specification, and you want to include 99.73% of your measurements, you do not need to change the 6 to a 3. Minitab divides the constant by 2 for these calculations.

Process tolerance
Enter the specification limits or the tolerance range to compare the measurement system variation to customer specifications. When you enter a specification limit or the tolerance range, Minitab displays a %Tolerance column in a table and in the Components of Variation graph. The %Tolerance column shows the percentage of the tolerance taken up by the measurement system variation.
  • Enter at least one specification limit: Enter one or both of the specification limits for the measurements to compare measurement system variation to customer specifications.
    Note

    Minitab can calculate the probabilities of misclassifying product when you enter at least one of the individual specification limits.

    • Lower spec: Enter the lower specification limit.
    • Upper spec: Enter the upper specification limit.
  • Upper spec - Lower spec: Select this option if you have both an upper and a lower specification limit, and you do not want to calculate the probabilities of misclassifying product. Enter the difference between the specification limits. This is also known as the tolerance range.
Historical standard deviation

Enter a known value for the total variation, which is the part-to-part variation plus the measurement system variation. Use the drop down to specify whether to use the historical standard deviation to estimate the process variation or to use the parts in the study to estimate the process variation.

When you select Use parts in the study to estimate process variation, Minitab displays a %Process column in a table and in the Components of Variation graph. The %Process column shows the percentage of process standard deviation taken up by each variance component.

Alpha to remove interaction term
Enter the alpha value (also called significance level) that is used to remove the interaction term from the model.
Usually, a significance level of 0.05 works well. A significance level of 0.05 indicates a 5% risk of concluding that the variability from the interaction term is significant when it is not.
Use a higher alpha level, such as 0.10 or 0.25, if you want to be more likely to keep the interaction in the model. Use a lower alpha level, such as 0.01, to be less likely to keep the interaction in the model.
Do not display percent contribution
Specify whether to display percent contribution.
Do not display percent study variation
Specify whether to display percent study variation.
Title
You can enter a custom title for the gage study.