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ANOM JMP v's Wheeler

Hi I am trying to replicate an ANOM that Wheeler did in Understanding Industrial Experimentation p60 (details attached)

 

I have attached the data set, I get different control limits for some reason, I set the alpha level at 0.10

Can you advise

 

 

 

Data TableRe: ANOM JMP v's Wheeler

The JMP help notes that JMP implements the methods from Nelson, et. al (2003).  link to JMP ANOM help 

The methodology in the Nelson book differs slightly from Wheeler's, for instance the measure of error differs. Therefore, the ANOM decision limits calculated in JMP will differ from those in the Wheeler book. You can find the Nelson ANOM book here (ANOM Book ).

 

For the equal case for means the decision limits are:

 

Re: ANOM JMP v's Wheeler

Thanks Karen, I asppreciate your response here

Re: ANOM JMP v's Wheeler

Hi Karen, I just looked at the book, your one of the the authors. So which is the best method and why ;0) 

Re: ANOM JMP v's WheelerWheeler uses ranges, JMP/Nelson uses standard deviations. Generally they are going to give you "similar" results. The key is plot your data, understand your measurement systems, use ANOM decision lines to guide your decision making. Since you are using JMP use the ANOM charts in JMP.Re: ANOM JMP v's Wheeler

Thanks, that really helps understanding the difference.  I have dealt with SD and ranges with the control charts.  The Shewhart chart and the Levey–Jennings charts for calculating control limits, where the Levey–Jennings uses SD.  Its important to understand these differences.