RE: Using two different means and control limits on one control c

[Steven_S_Prevette@rl.gov]

Yes, he did.  For an example, see page 198 of Quality, Productivity, and
Competitive Position.  I have my copy of OOC loaned out, I suppose the same
figure should be in there.  If you want to be able to show continual
improvement over time, you need to keep your history.  For an example, see
the control chart in http://www.hanford.gov/safety/vpp/asqarticle.pdf

Steve Prevette
Site Technical Authority for Statistical Trending
Environment, Safety and Health
Fluor Hanford, A Fluor Global Services Company
ASQ Certified Quality Engineer
steven_s_prevette@rl.gov
509-373-9371