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Control Charts with different Sample Sizes

J

jdm2008

#1
I'm trying to create a control chart. I have 4 sample groups with different numbers of parts in each group. When trying to construct a control chart and picking the right constant I need "n" the problem is, is that n is different for each sub group. Can I not construct the control chart using this forumula if each subgroup has a different number of parts?
 
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bobdoering

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#2
We need a lot more information than that to help. What kind of process? Why are the sample sizes different? Is it attribute or variable? Have you done a capability study? Where are you at in your control chart preparation?
 

Bev D

Heretical Statistician
Staff member
Super Moderator
#3
as Bob said, there are different formulas for handling variable sample size depending on what type of data you are charting and which chart type you are working with.
 
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