Remember my previous article on the quality pyramid where the very top element emphasizes the concept of “process?” One of the most powerful points to get across in any quality improvement ... [Read More]

Why do major change initiatives fail? It seems obvious: major change will not happen easily for a long list of reasons. However, if you feel your organization is overmanaged and underled with ... [Read More]

W. Edwards Deming has been dead for almost 16 years. In my opinion, he and Joseph Juran were the true quality giants of the 20th century. No one seems to talk about Deming much any more except to ... [Read More]

Do top managers still view financial performance as the sole indicator of success, despite mouthing platitudes about dazzled customers and fulfilled employees? Is there a point when reductions are ... [Read More]

“I suffer simultaneously from amnesia and déjà vu. I have the feeling that I keep forgetting the same thing over and over again.” —Steven Wright (surreal comedian) It all seems so ... [Read More]

Click here to read part 1 of this series. Analytic statistical methods are in very strong contrast with what is normally taught in most statistics textbooks, which describe the problem as one ... [Read More]

This is an expanded version of an article that Balestracci wrote for Quality Digest in December 2007.  --Editor I discovered a wonderful unpublished paper by David and Sarah Kerridge ... [Read More]

As this is my last column for Quality Digest, I’m delighted to announce that my distinguished predecessor, Donald J. Wheeler, will be writing this column again. You’ll be in good hands. When I got my master’s degree in statistics in 1980, jobs were plentiful for internal statistical consultants in corporate research and manufacturing. Their jobs involved educating scientists and ... [Read More]

Take a look at the control chart in figure 1. There are no observations outside the common-cause limits, but there are five special-cause flags: • Observation 5: Two out of three consecutive points greater than two standard deviations away from the mean • Observations 21 and 30-32: Four out of five consecutive points greater than one standard deviation away from the mean ... [Read More]

Suppose you had 16 months of data on an important process (as plotted on the run chart seen in figure 1). For improvement purposes, an intervention was made after the sixth observation to lower this key process indicator. This intervention is equivalent to creating a special cause for a desired effect. There is no trend as defined statistically (despite the trend downward of length ... [Read More]