Those of you familiar with W. Edwards Deming know that his Funnel Experiment ultimately shows that a process in control delivers the best results if left alone. Funnel Rule No. 4, also known as a “random walk”—i.e., making, doing, or building your next iteration based on the previous one—has been influencing Deming’s philosophy for the last 35 years. Isn’t it obvious that many times any resemblance between what one observes vs. Deming’s original intent is purely coincidental?

I’ve said it before: People don’t need statistics. They need to know how to solve their problems. All that’s needed are a few simple tools and a working knowledge of variation to be able to distinguish between common and special causes.

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