All Features
Donald J. Wheeler
Story update 9/8/2015: There was an error in the data set for columns "Skew" and "Kurt" in figure 7. The error has been corrected.
Clear thinking and simplicity of analysis require concise, clear, and correct notions about probability models and how to use them. Last month in part one we looked…
Mike Micklewright
You’ve heard of Bam Bam, Duran Duran, Zsa Zsa, so-so, tutu, and Reverend Tutu. And now we have... Gemba Gemba! But what is Gemba Gemba?
Quite simply, Gemba Gemba means going to the gemba for the purpose of observing others going to the gemba to ask, teach, learn, coach, and challenge. In this way…
Bob Emiliani
As both a participant and witness to the practice of lean management in higher education, I’d like to point out methodological errors in relation to how lean is practiced in industry.
People in industry who practice lean management correctly provide us with a standard to which we can compare the…
David Schwinn
I recently had a dream in which Adrian Bass, a colleague and friend for whom I have much admiration, asked me why I still care about quality management after all these years.
You can substitute Six Sigma for quality management because, in my mind, they are both part of a larger belief system that…
Fred Schenkelberg
Just, please, plot the data if you have gathered some time-to-failure data, or you have the breakdown dates for a piece of equipment. Any data really. It could be your review of your car maintenance records and notes and dates of repairs. You may have some data from field returns. You have a group…
Eston Martz
Statisticians say the darnedest things. At least, that’s how it can seem if you’re not well-versed in statistics.
When I began studying statistics, I approached it as a language. I quickly noticed that, compared to other disciplines, statistics has some unique problems with terminology. These are…
Gorur N. Sridhar
Quality and Six Sigma are often considered as links in a chain. For example, when quality is poor, many times the immediate response is, “Let’s improve it using Six Sigma.” But does Six Sigma, or any other program for that matter, really improve quality? Or, are they simply mirrors to let us know…
Joel Smith
Just 100 years ago, very few statistical tools were available and the field was largely unknown. Since then, there has been an explosion in available tools, as well as ever-increasing awareness and use of statistics.
Although most readers of this column are looking to pick up new tools or improve…
John Flaig
I have discussed the economics of project management numerous times in presentations all over the country, and based on the response to my message, I have to conclude that many people just don’t get it.
Let me again sound the wake-up call with a quote from V. S. Liebhold, co-author of the article…
Donald J. Wheeler
Some commonly held ideas about skewed probability models are incorrect. These incorrect ideas are one source of complexity and confusion regarding the analysis of data. By examining the basic properties of skewed distributions this article can help you to greater clarity of thought and may even…
David Schwinn
This month’s column was prompted by an especially thoughtful commencement address by Michael Ward, reproduced in the May/June 2015 issue of Imprimis (Hillsdale College). Ward, of course, encouraged the students to strive for success, but interestingly predicted that failure is inevitable and is to…
Eston Martz
If you’ve read the first two parts of this tale, you know it started when I published a post that involved transforming data for capability analysis. When an astute reader asked why Minitab didn‘t seem to transform the data outside of the capability analysis, it revealed an oversight that…
Eston Martz
In my last post, I told you how I had double-checked the analysis in a post that involved running the Johnson transformation on a set of data before doing normal capability analysis on it. A reader asked why the transformation didn’t work on the data when you applied it outside of the capability…
Eston Martz
I don’t like the taste of crow, which is a shame, because I’m about to eat a huge helping of it.
I’m going to tell you how I messed up an analysis. But in the process, I learned some new lessons and was reminded of some older ones I should remember to apply more carefully.
This failure starts in…
Joel Smith
Last month, the ESPN series Outside the Lines reported on baseball pitchers suffering serious injuries from being struck in the head by line drives, and the efforts that Major League Baseball (MLB) is making toward having protective gear developed for pitchers.
You can view the report here if you…
Davis Balestracci
This is a continuation of my last column, which I’ve written to honor my late dad who loved golf. As promised, let’s look at the Masters golf tournament final four-round scores for the 55 players who survived the cut. We’ll analyze and then give it a twist based on the ongoing enumerative vs.…
Matthew E. May
No, this isn’t an opinion piece or in any way a critique. It’s more like a public service announcement for business professionals in the job market, looking for a strategy position with a market leader.
Like most regular users of LinkedIn, I constantly get pushed notices about “jobs I might be…
David Schwinn
“If we are to achieve a richer culture, rich in contrasting values, we must recognize the whole gamut of human potentialities, and so weave a less arbitrary social fabric, one in which each diverse human gift will find a fitting place.”
—Margaret Mead
This month’s article comes from the…
Brian Maskell
T here are three ways in which a standard costing system is typically used in a manufacturing company:
1. Performance measurement 2. Decision making 3. Inventory valuation
From an accounting perspective, performance measurement and decision making are part of a company’s management accounting…
Fred Schenkelberg
Control charts provide an ongoing statistical test to determine if a recent reading or set of readings represents convincing evidence that a process has changed from an established stable average. The test also checks sample-to-sample variation to determine if the variation is within the…
Patrick Runkel
I’ve never understood the fascination with selfies.
Maybe it’s because I'm over 50. After surviving the slings and arrows of a half a century on Earth, the minute or two I spend in front of the bathroom mirror each morning is more than enough selfie time for me.
Still, when I heard that Microsoft…
Bruce Hamilton
The last few weeks for me have been all things Shingo, including a presentation at the Shingo Institute’s International Conference three weeks ago in Provo, Utah, followed by four days of Shingo Institute workshops at Vibco in Richmond, RI. Questions at both events about assessing for enterprise…
Patrick Runkel
It’s usually not a good idea to rely solely on a single statistic to draw conclusions about your process. Do that, and you could fall into the clutches of the “duck-rabbit” illusion shown below.
If you fix your eyes solely on the duck, you’ll miss the rabbit—and vice-versa.
If you’re using…
Brian Maskell
It is vitally important for lean people to know nothing when working on improvement. This sounds like a crazy idea, but it is another 100-percent turnaround from traditional management thinking.
To do this, it’s necessary to do three things: • Understand how lean thinkers go about radically…
Rip Stauffer
Recently, in one of the many online discussion groups about quality, Six Sigma, and lean, this question was posed: “Can X-bar R and X-bar S be used interchangeably based on samples size (n) if the subgroup size is greater than one and less than eight?” Answers varied, of course.
In some of these…