Hi! I'm the new kid in the forum. I used to work a lot with the product SAS QC. I love that product so much so I use my SAS QC manual as statistical reference.
Well, my question is about the calculation of c5(Ni) parameter i to calculate Statistical control limits for the SChart in the XSChart procedure.
The documentation about calculations for control limits in XSChart describes the calculation of c4(Ni) parameter as a function of the gamma function, but nothing is mentioned about the c5(Ni) parameter. The only reference is that c5(Ni) is the standard error of the standard deviation of the subgroup i. I've done some web searches and found something related but, I want to be sure that they are referring to the same concept.