topic Re: Variable Control limit plot in Discussions

Variable Control limit plot

jasongao — Tue, 12 Nov 2019 18:22:45 GMT

Hello,

I have a data table like below, with variable control limits. I would like to generate a control plot with spec lines. I can do it in overlay plot, but is there anyway I can do it in Fit Y and X plot, or control chart? Because I would like to modify the lengend for different groups, add fitting line etc, which I could not do on overlay plot.

Thanks!

Data	Time	LCL	UCL	Target	Group
6369.36	11/8/2019 13:07	4000	7081	5540	a
6220.436	11/8/2019 15:15	4000	7081	5540	b
6553.124	11/9/2019 16:15	4000	7081	5540	a
6659.495	11/9/2019 17:54	4000	7081	5540	a
6153.043	11/10/2019 6:49	5000	8081	6540	b
6587.26	11/10/2019 18:40	5000	8081	6540	a
6922.839	11/10/2019 22:53	5000	8081	6540	b
6608.837	11/11/2019 0:44	5000	8081	6540	a
7134.386	11/11/2019 23:22	5000	8081	6540	b
6936.434	11/12/2019 0:51	5000	8081	6540	a
7339.771	11/12/2019 7:34	5000	8081	6540	b

Re: Variable Control limit plot

cwillden — Tue, 12 Nov 2019 18:40:10 GMT

You could do it in Graph Builder if you stack your Data, LCL, UCL, and Target columns by dropping the resulting Label column into the Overlay drop zone. Are you sure you want your specs on your control chart? That often drives bad behavior like not reacting to out of control points that are in spec. Sorry, I know that is unsolicited advice.

Re: Variable Control limit plot

tonya_mauldin — Tue, 12 Nov 2019 19:03:21 GMT

You can do this Control Chart Builder with a phase variable. Here is a blog post that details the steps.

https://community.jmp.com/t5/JMPer-Cable/Creating-a-phase-control-chart-with-historical-limits-for-each/ba-p/33738

Re: Variable Control limit plot

cwillden — Tue, 12 Nov 2019 19:22:02 GMT

The only downside to that is you can't fix your control limits. They will always be re-estimated from the data within each phase.

Re: Variable Control limit plot

tonya_mauldin — Tue, 12 Nov 2019 19:36:52 GMT

I'm not sure which method you are refering to when you say "They only downside to that is you can't fix your control limits." My blog post details how to fix your control limits for each phase. You can specify a different set of historical control limits for each phase of your data in Control Chart Builder.

Re: Variable Control limit plot

cwillden — Tue, 12 Nov 2019 19:46:46 GMT

response got duplicated

Re: Variable Control limit plot

cwillden — Tue, 12 Nov 2019 19:45:56 GMT

Sorry, I hadn’t read the blog post and didn’t realize you addressed that capability in the blog. I didn’t know that was possible to do

Re: Variable Control limit plot

Mark_Zwald — Wed, 13 Nov 2019 03:56:17 GMT

Create a spec limit property for the column(s) that have specs and make sure you check the box that says "Show as Graph Reference Lines". Then any visual you make with those columns will show lines for the spec limits.

Similarly, you can also define control limits as a column property and they would show up in a control chart.