% of Contribution or % of Study Variation? Using Minitab - Gage R&R
Hi all
By Using Minitab, when GR&R study is conducted (crossed method), what are the conditions when % of contribution or % of study variation is a more appropriate metric to use?
Thanks in advance
Re: % of Contribution or % of Study Variation? Using Minitab - Gage R&R
% of study variation is %GRR. This is the appropriate metric to use to determine whether a gage is suitable for use in process control, or in continual improvement (hypothesis test, DOE's, etc.).
% contribution is a tool, not a metric. Its only purpose is to point you to the parameter (i.e., repeatability, reproducibility, operator x part interaction, etc.) that contributes the most to the measurement variation. That allows you to focus on the correct parameter to reduce measurement variation.
__________________
"A fool can learn from his own experiences; the wise learn from the experience of others." - Democritus, 460-370 B.C.
Re: % of Contribution or % of Study Variation? Using Minitab - Gage R&R
In that case why Minitab displays a Total GR&R % in % Contribution?
It seems just to be the addition of EV and AV.. not the square root of (EVsqure + AVsquare). am I right?
Re: % of Contribution or % of Study Variation? Using Minitab - Gage R&R
Minitab bases the % Contibution on the variances (VarComp), which are additive. The variance (VarComp) of the repeatability is EVsquared. The variance of the reproducibility is AVsquared.
__________________
"A fool can learn from his own experiences; the wise learn from the experience of others." - Democritus, 460-370 B.C.
% of Contribution or % of Study Variation? Using Minitab - Gage R&R
Re: % of Contribution or % of Study Variation? Using Minitab - Gage R&R
Linear Mode
