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By Donald J. Wheeler

The number of major hurricanes in the Atlantic since 1940 (as we considered in my February column, “First, Look at the Data”) are shown as a histogram in figure 1, below. Some analysts would begin their treatment of these data by considering whether they might be distributed according to a Poisson distribution.

The 68 data in figure 1 have an average of 2.60. Using this value as the mean value for a Poisson distribution, we can carry out any one of several tests collectively known as “goodness-of-fit” tests. Skipping over the details, the results show that there’s no detectable lack of fit between the data and a Poisson distribution with a mean of 2.60. Based on this, many analysts would proceed to use techniques that are appropriate for collecting Poisson observations. For example, they might transform the data in some manner, or they might compute probability limits to use in analyzing these data. Such actions would be wrong on several levels.

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By Quality Digest

Regarding H. James Harrington’s video interview with Dirk Dusharme (“Profiles in Quality: Jim Harrington--Episode 2,” Harrington is highly recognized in the quality management society of China and has made significant contributions to Chinese quality management progress.

The Chinese government plays an important role in business, as pointed out by Harrington. Its responsibility is to ensure that products made in China are safe for consumption.

The Chinese government does not dictate what business should do. Like all business in other countries, Chinese business is led by market demands and consumers’ requirements. If a U.S. importer decides to order lower-grade products for its customers or fails to provide adequate quality specifications that meet U.S. standards, the U.S. consumers will get precisely what the importer ordered. It is not fair for the news media or consumers to blame Chinese producers for providing exactly what they were asked to produce.

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By Nicolette Dalpino



A Macquarie Island beach
(Photo: M. Murphy/Public domain)


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By Quality Digest

A Tell Tool technician using the Hawkeye borescope for part inspection

A mix of mission-critical components for high-stakes applications makes visual inspection a key part of the process for Westfield, Massachusetts, manufacturer Tell Tool Inc. The company manufacturers complex machined castings, forgings, and wrought material for aircraft and spacecraft, so quality control is important to Tell Tool, an ISO 9001- and AS9100-registered company.

For products such as electronic engine controls, hydromechanical fuel controls, auxiliary power units, pump housings, and jet fuel control housing, blueprint requirements are stringent. “If the part doesn’t meet blueprint tolerances, Tell Tool must reject it,” says Michael Ostrowski, head of Tell Tool’s purchasing team. “There’s no repair allowed; the customer will not receive the part. It’s that critical. If a burr were clogging a passageway when the engine is calling for fuel, you could have a catastrophic failure of the engine.”

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By Davis Balestracci

This column is in honor of the first anniversary of my late father’s death. In his last days, Dad enjoyed watching golf, and I’d often join him. Watching the recent British Open, I thought I would apply some basic statistical principles to the final scores.

For example, 83 people made the cut, and the ANOVA of their individual round scores is shown in figure 1.

The two ANOM plots are shown in figures 2 and 3.

Another interesting statistic is the standard deviation of an individual round: square root 8.975 ~ 3. Using the standard Bartlett and Levene tests for equality of variances, I tested the 83 golfers as to whether this was consistent for all of them:

p-value Bartlett: 0.891

p-value Levene: 0.983

Depending on luck and other random factors, an individual’s score could swing by ± 6-9 strokes in a round!

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By Dirk Dusharme @ Quality Digest

Why is it that we have to be at the end of our rope, all hope lost, and near death’s door, before we “see the light?” Near-death experiences; prison time; losing your job, your house, your family; all seem to clarify our focus about where we’ve gone wrong and how we can do better. Once there’s no way to go but up, confession, repentance, and forgiveness all seem so easy.

I’m not speaking from a religious perspective. I’m speaking in even broader terms. Why do we wait until the system breaks before we decide that, gee, maybe we haven’t been as honest as we should be? You need to look no further than recent Quality Digest online or print articles to see where I’m coming from.

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By Quality Digest

In the world of nationwide retail, margins are tight, timing is essential, and inventory management will make or break a company’s success. Third-party logistics (3PL) providers work with major retailers and provide a broad range of fulfillment services. They make the complex process of delivering goods through the entire distribution process as efficient and cost-effective as possible.

Westcoast Warehousing, based in Southern California, is a 3PL that partners with some of the largest and best-known retailers in the United States, including JCPenney, Sears, and Kohl’s. Key services offered by Westcoast Warehousing include pick-and-pack, and direct-to-store (DTS) replenishment, as well as options that allow retailers to ship product in bulk directly to Westcoast Warehousing, which maintains a six- to eight-week supply of inventory on the retailer’s behalf.

Retailers place weekly orders and product is shipped accordingly via prepacked boxes. This relieves retailers of the massive infrastructure and expense associated with in-house logistics and inventory management, and provides significant cost-savings combined with increased efficiency and flexibility.

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By Carey Wilson

In autumn 2006, customer demand was exceeding production capacity at Singer Sewing Machine facilities. To meet the capacity constraints, Don Fletcher, CEO of Singer’s parent company, SVP Worldwide, headquartered in Hamilton, Bermuda, decided to launch lean Six Sigma into all facilities around the world.

Singer had been building sewing machines for more than a century utilizing old-fashioned methods of manufacturing, and the need for change was undeniable. The problem was a lack of data-driven procedures, which sometimes resulted in inefficient processes being accepted as business as usual. The situation clearly needed to change.

First there had to be a champion for change. With that realization in mind, Mike Simmons, SVP Worldwide’s vice president of global human resources, took on the challenge. Simmons decided to partner with Air Academy Associates in the worldwide launch of lean Six Sigma at Singer. The decision to start from the top down was clearly the right choice, and all top management went through a one-week champions’ training on how to launch a successful lean Six Sigma implementation. Greg Atwater, director of worldwide quality and Six Sigma, was brought on board to travel throughout the organization setting up and implementing the plan to train Black Belts and Green Belts.

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By Quality Digest

Why, Why, Why, Why, Why

I agree with Craig Cochran that complex problems are difficult to solve or tackle using the 5 Whys method (“Don’t Fail Your Customers With the Five Whys,” February 2009). Companies and consultants have a tendency to want to use the 5 Whys method as a pill for all illnesses.

Another problem with the 5 Whys method is that by the time you get to the fifth why, the root cause of a problem inevitably ends up being something along the lines of “the employee causing the error is not motivated.”

There are, however, a lot of cases where the 5 Whys method has worked nicely. Normally it’s with simpler or straight- forward situations, or where there’s supporting data for the problem-solving team to explore during the 5 Whys process. I have seen instances where after a lot of complicated Six Sigma or failure mode analysis, problems were never solved. When we applied the 5 Whys correctly and, in a brutally honest way, we got to the bottom of the issue in no time.

--Paolo Chiappina


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By Dirk Dusharme @ Quality Digest

You might notice that the copy of Quality Digest you’re holding in your hand is a little light. You’ve been telling us for years that we had too many advertising pages, so we delivered with fewer pesky ads to interrupt your reading pleasure. Is that customer service or what? Of course, we didn’t plan it that way.

As to why we’re skinny this month, our “Quality Curmudgeon” Scott Paton has analyzed the woes facing the publishing industry in his column, so I won’t do that here. Just flip to his column at the end of the magazine (which is much closer than it used to be) when you’re done here.

Obviously the print news industry, including trade publications, is quickly changing. Fortunately for us we have seen it coming and have been improving our online presence and adding exclusive content.

In case you haven’t been to our web site recently, here’s a brief overview of what’s available:

The key feature is the addition of video. We both produce our own content and solicit content from others. The site currently hosts 50 videos, with about two videos being added each week. The most popular videos have been our Technorazzi and Viewpoint series.