Industrial Statistics with Minitab

13.4 R&R Study for the Data in File ‘RR_CROSSED’

In this case, the adequate approach is a crossed design since each operator measures all parts several times. Thus, go to: Stat > Quality Tools > Gage Study > Gage R&R Study (Crossed)

With Minitab, the use of ANOVA is recommended, which is actually the default option. The Xbar and R method is only advisable for comparison with other studies conducted with this method.

Options, with all default values:

Process tolerance refers to the tolerance interval for the measured magnitude. If this value is specified, Minitab displays which percentage of the amplitude is due to the variation of the measurement system and which percentage is due to each of its components. Furthermore, if the corresponding option is activated, the probabilities of erroneous classification are shown (seen later on).

Historical standard deviation. If the historical standard deviation of the measured magnitude is known, it can be specified here. Minitab will then show the percentage of that total variability due to the measurement process and each of its components.

The results shown in the Session window can be divided into three parts: (1) tables of the analysis of variance; (2) table of the variance components; (3) table of the study of variation.

13.4.1 ...