Re: Are these examples of stable systems with points outside the

[Richard White <RichWhite@orchardavenue.com>]

Thanks to everyone!

I appreciate each and every one of your many thoughtful responses. Reading
them all, I realized that I neglected to mention in my original note that
these results came from a simulation that I'm reporting on, not from a real
life system. I apologize for the fact that my careless omission led several
of you to take the time to put together some responses that would have been
extremely helpful if this were real.

I was surprised by some responses, though. Some folks suggested that maybe I
should not have used an np chart in this situation, or that I didn't have
enough data to draw a meaningful control chart. Yet is this situation not
virtually identical to the Red Bead Experiment, in which Deming uses an np
chart on defect data obtained over four production periods to demonstrate
that the system is stable?

Rich White
Orchard Avenue