R
Reach
Hi guys,
I'm doing some research and trying to understand the meaning of numbers resulted from Gage R&R.
I got an example set of data for a Gage R&R that shows following results:
----------------------------------------------------------------------
Two-Way ANOVA Table With Interaction
Source DF SS MS F P
Part 2 0.0001881 0.0000941 397.099 0.000
Operator 2 0.0000017 0.0000008 3.526 0.131
Part * Operator 4 0.0000009 0.0000002 2.520 0.077
Repeatability 18 0.0000017 0.0000001
Total 26 0.0001925
Alpha to remove interaction term = 0.25
Gage R&R
%Contribution
Source VarComp (of VarComp)
Total Gage R&R 0.0000002 1.96
Repeatability 0.0000001 0.88
Reproducibility 0.0000001 1.07
Operator 0.0000001 0.63
Operator*Part 0.0000000 0.45
Part-To-Part 0.0000104 98.04
Total Variation 0.0000106 100.00
Study Var %Study Var
Source StdDev (SD) (6 * SD) (%SV)
Total Gage R&R 0.0004562 0.0027374 13.99
Repeatability 0.0003066 0.0018397 9.40
Reproducibility 0.0003378 0.0020269 10.36
Operator 0.0002579 0.0015472 7.91
Operator*Part 0.0002182 0.0013094 6.69
Part-To-Part 0.0032290 0.0193739 99.02
Total Variation 0.0032611 0.0195663 100.00
Number of Distinct Categories = 9
----------------------------------------------------------------------
I have found equations and was able to do manual mathematics to obtain those results. I understand (or at least i think i do) why %contributions add up to 100% and how that number is used (or explain the meaning of that number to layperson).
However, although i can follow how to calculate those numbers, I don't understand why get the second set of numbers with SD's and %Study Var's, and how they are used.
I know the criteria for %contribution, and %StudyVar (i asked you guys for the help on that as well last week or so ), but i'm now trying to understand actual meaning of them.
I guess the question that confuses me the most is the use of percentages (%) for study variations. It seems natural when we find percentages of certain things, we want that to add up to 100%.
Again, i understand they dont add up to 100 because we're using SD's but don't understand why we use it.
I'm sorry i'm rambling on and my wording is really confusing. I guess i'm not exactly sure what to ask since i recently started studying about gage r&r and only have very crude knowledge about the test.
Thanks!!!
ps. sorry for the messy data; i'm new to pasting data, and posting thread skills><
I'm doing some research and trying to understand the meaning of numbers resulted from Gage R&R.
I got an example set of data for a Gage R&R that shows following results:
----------------------------------------------------------------------
Two-Way ANOVA Table With Interaction
Source DF SS MS F P
Part 2 0.0001881 0.0000941 397.099 0.000
Operator 2 0.0000017 0.0000008 3.526 0.131
Part * Operator 4 0.0000009 0.0000002 2.520 0.077
Repeatability 18 0.0000017 0.0000001
Total 26 0.0001925
Alpha to remove interaction term = 0.25
Gage R&R
%Contribution
Source VarComp (of VarComp)
Total Gage R&R 0.0000002 1.96
Repeatability 0.0000001 0.88
Reproducibility 0.0000001 1.07
Operator 0.0000001 0.63
Operator*Part 0.0000000 0.45
Part-To-Part 0.0000104 98.04
Total Variation 0.0000106 100.00
Study Var %Study Var
Source StdDev (SD) (6 * SD) (%SV)
Total Gage R&R 0.0004562 0.0027374 13.99
Repeatability 0.0003066 0.0018397 9.40
Reproducibility 0.0003378 0.0020269 10.36
Operator 0.0002579 0.0015472 7.91
Operator*Part 0.0002182 0.0013094 6.69
Part-To-Part 0.0032290 0.0193739 99.02
Total Variation 0.0032611 0.0195663 100.00
Number of Distinct Categories = 9
----------------------------------------------------------------------
I have found equations and was able to do manual mathematics to obtain those results. I understand (or at least i think i do) why %contributions add up to 100% and how that number is used (or explain the meaning of that number to layperson).
However, although i can follow how to calculate those numbers, I don't understand why get the second set of numbers with SD's and %Study Var's, and how they are used.
I know the criteria for %contribution, and %StudyVar (i asked you guys for the help on that as well last week or so ), but i'm now trying to understand actual meaning of them.
I guess the question that confuses me the most is the use of percentages (%) for study variations. It seems natural when we find percentages of certain things, we want that to add up to 100%.
Again, i understand they dont add up to 100 because we're using SD's but don't understand why we use it.
I'm sorry i'm rambling on and my wording is really confusing. I guess i'm not exactly sure what to ask since i recently started studying about gage r&r and only have very crude knowledge about the test.
Thanks!!!
ps. sorry for the messy data; i'm new to pasting data, and posting thread skills><