topic Re: How do I get a compared with standard Kappa in an Attribute Guage Chart? in Discussions

How do I get a compared with standard Kappa in an Attribute Guage Chart?

Noeleen20350465 — Fri, 17 Jan 2025 06:01:01 GMT

I've created a guage chart for 5 raters, who rated 20 parts against a standard (1). I've rated each as correct (1) or incorrect (2). I've followed the instructions here...https://www.jmp.com/support/help/en/18.1/index.shtml#page/jmp/attribute-gauge-charts.shtml#

In the agreement comparisons for raters with the standard, I get this...

Why am I not getting a Kappa rating? I have set my data table up the same as the JMP example

And they get this answer...

I'm using JMP Pro 18

How do I get a Kappa for the rater compared with the standard?

Thanks

Re: How do I get a compared with standard Kappa in an Attribute Guage Chart?

jthi — Fri, 17 Jan 2025 14:41:16 GMT

Could it possibly be related to the situation that you only have single value for references?

If you change all the values in JMP's example table (Attribute Gauge.jmp) to 1 you will get 0 Kappa values for Agreement comparisons with standard

Re: How do I get a compared with standard Kappa in an Attribute Guage Chart?

Dan_Obermiller — Fri, 17 Jan 2025 17:04:00 GMT

You don't provide the full details on what you are rating, but I believe that @jthi is on the right track here. In order to get Kappa values you need to have the same possibilities for the standard and the raters. You currently only have 1's for the standard, but the raters have 0 and 1 as possibilities.

Typically an attribute chart is used when you are rating an item on a scale, say 1 to 5. The attribute gage analysis then compares the raters to see if they are getting the correct "standard" value. In the JMP table you would enter the rating from each of the panelists rather than just if they are correct or not.

With your data, even if there are only two possibilities (1 and 0), only having a standard of 1 is not a complete picture. You can see if your raters can identify the 1 level, but how do they do when the other level (the 0) is what they should see? In other words, do they ever see a part without the feature and incorrectly say the feature is there? That is important to know as well, and is needed for JMP to calculate Kappa.

As a quick test to see if this truly resolves the problem, enter one row at the bottom with a standard of 0, enter values of 0 for the raters and run the analysis. I expect you will then have a Kappa value.

Re: How do I get a compared with standard Kappa in an Attribute Guage Chart?

Noeleen20350465 — Sat, 18 Jan 2025 07:59:15 GMT

@jthi @Dan_Obermiller

Thank you both very much, you were both correct.

When I changed the standard to include 0 I got a Kappa for the rater against standard.