Donald J. Wheeler
Last month we provided an operational definition of when measurement systems are equivalent in terms of bias. Here we will look at comparing the within-instrument measurement error between two or...
Edwin Amenta
Ever since sportswriter Henry Chadwick popularized the box score in the 19th century, baseball fans have had a love affair with statistics. Many can recite records like Joe DiMaggio’s 56-game hitting...
Donald J. Wheeler
As soon as we have two or more instruments for measuring the same property the question of equivalence raises its head. This paper provides an operational definition of when two or more...
Davis Balestracci
In most healthcare settings, workers attend weekly, monthly, or quarterly meetings where performances are reported, analyzed, and compared to goals in an effort to identify trends. Reports often...
Teofilo Cortizo
Within maintenance management, the term MTBF (mean time between failures) is the most important key performance indicator after physical availability.
Unlike MTTF (mean time to failure), which...
Donald J. Wheeler
Managers the world over want to know if things are “in control.” This usually is taken to mean that the process is producing 100-percent conforming product, and to this end an emphasis is placed upon...
Davis Balestracci
During recent visits to Twitter and LinkedIn, I’ve become increasingly shocked by the devolution of the posts to vacuous nonsense. I felt a Network moment of, “I’m mad as hell, and I’m not going to...
Scott A. Hindle
‘Process Capability: What It Is and How It Helps,” parts one, two, three, and four, discussed Alan’s development in the field of process capability1 He’d learned about the mistakes that can be made...
Donald J. Wheeler
With the click of your mouse you can turn a list of values into a bubble plot. No thought or effort is required. Simply sit back and let the software gods do the heavy lifting of transforming...
Tom Siegfried
If Fyodor Dostoyevsky had been a mathematician, he might have written a book called Crime and Statistics. However, since “statistics” doesn’t have quite the same ring as “punishment,” it wouldn’t...
Davis Balestracci
“People think that if you collect enormous amounts of data you are bound to get the right answer. You are not bound to get the right answer unless you are enormously smart.” —Bradley Efron
There has...
Donald J. Wheeler
Story update 1/15/2019: Thanks to the sharp eye of Dr. Stan Alekman, who spotted an inconsistent value in figure 2, I discovered an error in the program used to construct the table of critical...
Anthony D. Burns
The control chart is at the heart of the very definition of quality. It is central to building, maintaining, and predicting quality into the future. However, control charts today, more often than not...
David Currie
This is part three of a three-part series. Read about good metrics in part one and bad metrics in part two.
Have you ever had occasion to dread a metric reviewed month after month, where the metric...
Quality Digest
Annalise Suzuki, director of technology and engagement at software provider Elysium Inc., spoke to Quality Digest about the importance of model-based definitions (MBD) for data quality, validation,...
Anthony Chirico
Everybody wants to design and conduct a great experiment! To find enlightenment by the discovery of the big red X and perhaps a few smaller pink x’s along the way. Thoughtful selection of the best...
Jody Muelaner
In this article I will show that the conventional method for calculating uncertainty is not always reliable. In fact, it is generally only exact when the measurement can be represented by a simple...
Scott A. Hindle
Walter Shewhart, father of statistical process control and creator of the control chart, put a premium on the time order sequence of data. Since many statistics and graphs are unaffected by this, you...
Minitab LLC
Machine learning as a tool in your analytical toolkit can help accelerate the discovery of insights in data that can create a more efficient manufacturing process and drive innovation.
Machine...
Donald J. Wheeler
Process behavior charts are the interface between your data and your brain. But you have to begin by making a choice about which type of chart to use. You can either plot the individual values...