Talk:Process capability index/Archives/2017

Confusing
The definitions of Cp, Cpk here are exactly the same as for Pp, Ppk in the article Process performance index. Are they meant to be the same and just used under different conditions (under statistical control, not under statistical control)? Or are they meant to be different? A statement about this is required. — Preceding unsigned comment added by 217.13.68.110 (talk) 06:55, 18 July 2017 (UTC)