Q
I am analyzing a process capability study and am not sure which capability index applies. For our thirty piece sample, I am looking at the Ppk because the subgroup is 1. Since the subgroup is one, I want to use the actual standard deviation.
Our other study is made up of thirty subgroups. The subgroup size is 10. For this study I am looking and the Cpk because it uses an estimated standard deviation.
Am I correct in how I am using the capability indexes?
Our other study is made up of thirty subgroups. The subgroup size is 10. For this study I am looking and the Cpk because it uses an estimated standard deviation.
Am I correct in how I am using the capability indexes?