AIAG's MSA III Edition - Forms and Formulas - Attribute Gage R&R

[Varadhan]

Hi All

Can anyone explain me

1. Why no forms were included for in Sample Forms (Page 215) for conducting Attribute Gage R & R ?
2. Do you suggest that I can use Table 12 ( Page 127) for collecting data and use format in page 131 for computations?
3. Do you recommend calculation of " kappa" before computing Attribute Measurement results?

Warm regards

K S Varadhan

 

[Atul Khandekar]

Varadhan,

1&2.
The sample forms given for Variable R&R are not just the reporting formats, they serve the purpose of explaining the various steps in the complex calculations involved- when should you take horizontal (or vertical) totals and why, etc etc.
Comparatively, attribute R&R calculations are simpler. IMO, you can use the formats given on p127 & 131 s they are. You can also design your own.

3.
The question is not very clear to me. Kappa IS calculated on the basis of results obtained by different appraisers. (Degree of agreement between operators) If you also have the 'Reference Decision' you can calculate kappa w.r.t. the reference (Degree of agreement with Reference).

-Atul.

 

[Varadhan]

Dear Atul

Thanks for your valuable clarifications. Regarding Q3 let me clarify. Is it neccassary to calculate kappa before computing effectiveness,false alarm, miss etc? Suppose if calculated value of kappa is below 0.75, what we should do? Do we change appraisers before computing effectiveness,false alarm, miss etc.,? BTW Would you post me a complete workout on Attrbute Gage R & R conducted at your end showing steps at <[email protected]>

Regards

K S Varadhan

 

[Atul Khandekar]

Varadhan,

There are two kappa evaluations:
1. for Agreement between operators and
2. Agrrement of each operator with Reference decision.
(See note at the end of p129)

The results of Effectiveness calculations may contradict the kappa evaluations as mentioned in the manual example. Please also read the "Concerns" expressed on p132 of the manual.

IMO, you can calculate effectiveness without calculating the kappa. But please note that when you calculate effectiveness, you already have the data to calculate kappa.

For an example of effectiveness calculation, withou kappa, please refer to thread:
https://elsmar.com/elsmarqualityforum/threads/5347/

-Atul