Re: Methods to Determine Special vs. Common Cause

[demingtw <demingtw@ms17.hinet.net>]

> >I was wondering, are there any accepted methods to separate common causes
> >from special causes besides control charts?

Bill Latzko replied
> No!

WMack's wondering is indeed one of  most sophiscated ones for us.
Bill's zen-like answer was quite like WED and I think he might be right.
The power of control charting is that it cover the'states' and the
'processes'( if we trace the operational parts) of the system we are concerned
with but in some cases, we cannot have such 'data'.
I think we need to think from the starting points.
What is the 'purpose' of WAS and WED's 'control chart thinking'?
The ' economics' and continual improvement.
IMHO, various 'understanding' conjectures were proposed by many people.
For example, Dr. Brian Joiner in his 4GM proposed one 'quick criterion' for it
and David Hume proposed another one for historical understanding.
This might be related with our recent discussions of Mr. Sarason and/or
Deming, for example.
What is our aim in this pursuit?
I hope we can have some deeper plays in this one.

Hanching Chung
http://www.deming.com.tw
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