jrubio said:
I will translate exactly the sentence, May be I am wrong.
Sorry for My English is getting worse.
"It can be calculated the Cpk index if the process is stable, PPk it should be used for a process Chronic unstable but with a result that meet specification"
Example.
1) 5 parts Av=2 Sigma=3 ppk1=2.1
2) 5 parts Av=2 Sigma=2.9 ppk2=2.3
3) 5 parts Av=2 Sigma=2 ppk3= 2
ppk due to the Capability is changing, Not Stable,
...
17) 5 parts Av=2 Sigma= 1 ppk97=2
18) 5 parts Av=2 Sigma= 1 Cp1=2
19) 5 parts Av=2 Sigma= 1.01 Cp2=2.1
20) 5 parts Av=2 Sigma= 1.01 Cp2=2.1
Now Stable finished.
Total = 100 parts.
The only serious doubt I really have is the minimumn number of points needed to say than a distribution is normal, 5, 10 ??????