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View Full Version : Is minitab 'AIAG compliant' to perform GR&R, linearity and bias study?


Anatta
10th April 2006, 05:59 AM
Hi all,

our organization is using minitab as a standard siftware to perform GR&R, linearity and bias study.

particularly for linearity and bias, the output is different from what is stated in AIAG's MSA ref manula 3 rd edition.

In AIAG MSA Referenece manual 3rd edition, page 86, it mentioned that Bias is acceptable at the alpha level if zero falls within the 1 minus alpha confidence bounds around the bias value.

As for linearity, Minitab doesn't culculate the t value to determine linearity....

so can we still perform the MSA and tell the auditors that we doing it with minitab just that the output is diffrent?

rgds,
Anatta:thanx:

apestate
10th April 2006, 06:22 AM
Try it with the excel spreadsheet posted in this thread

http://Elsmar.com/Forums/showthread.php?t=6950&referrerid=4520

Anatta
11th April 2006, 11:09 PM
atetsade,

thanks a lot!

however, what i am to achieve here is that, whether we can consolidate one software to determine all our MSA study.

well, actually Minitab is quite well known...althought the output is diffrent from the ones spelled out in MSA ref manual....if we can use it as well, we do not want to engage in too many manual work sheet....

please enlighten...:cool: :thanx:

Anatta
17th April 2006, 10:46 PM
Hi all.....calling anyone that can help....

As discuss previous week, our organization is using Minitab to perform MSA study. And the output for Mintab is P value & %linearity or % bias, which is very different from the one results in AIAG reference manual.

For Bias study, how much of %Bias and how much of p value onwards from the Minitab output we need to consider the study fail and need to perform improvements. For AIAG reference guideline only spell out, if zero fall in between the 95% confidence interval of the bias, it is considered acceptable.

As for linearity, how much of % linearity, R-sq & P value from Minitab output is consider acceptable? In AIAG reference manual, we have to calculate the t-value.

There is a guideline for GR&R, where if the %R&R is less than 10%, it's acceptable. 10% ~ 30%, it's an indicator of rooms for improvement and >30% is unacceptable.

We just do not get the acceptable limit for Bias & Linearity.

Can someone please help me on these......

:(

Caster
18th April 2006, 05:52 PM
Hi all.....calling anyone that can help....

As discuss previous week, our organization is using Minitab to perform MSA study. And the output for Mintab is P value & %linearity or % bias, which is very different from the one results in AIAG reference manual.

For Bias study, how much of %Bias and how much of p value onwards from the Minitab output we need to consider the study fail and need to perform improvements. For AIAG reference guideline only spell out, if zero fall in between the 95% confidence interval of the bias, it is considered acceptable.

As for linearity, how much of % linearity, R-sq & P value from Minitab output is consider acceptable? In AIAG reference manual, we have to calculate the t-value.

There is a guideline for GR&R, where if the %R&R is less than 10%, it's acceptable. 10% ~ 30%, it's an indicator of rooms for improvement and >30% is unacceptable.

We just do not get the acceptable limit for Bias & Linearity.

Can someone please help me on these......



Forget about QS/TS, it is your business to run the way you see fit!

Just state in your MSA procedure that you use Minitab. Call out the acceptance criteria you will use and let it go.

If and when a customer or auditor issues a CA you can deal with it then.

The more confident you are in your system, the less likely you will ever be challenged.

If it makes sense to your company and is mathematically correct what can they say?

TS/QS both allow alternate methods as long as they meet the intent.

Hey, you're doing MSA and that's 99% of the battle right there!

Do what you want first, then bend TS/QS to your will!

Chances are no one at the customer or auditor really understand it anyway....at least not enough to go toe to toe with someone who can rattle off p values at them!

Good luck!