All Features
Greg Fox
It’s that time of year again. The time when eggs get nogged, pudding gets figgy, and it becomes socially acceptable to speak in rhyme. So on that note, and with apologies to Clement Clarke Moore, I bring you this timely and heartfelt public service announcement. Enjoy.
’Twas the week before…
Davis Balestracci
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…
Barbara A. Cleary
Statistics has gotten a bad rap. People love to quote Mark Twain (“There are lies, damn lies, and statistics,” alternatively attributed to Benjamin Disraeli), Vin Scully (“Statistics are used much like a drunk uses a lamppost: for support, not illumination”), or Stephen Leacock (“In ancient times…
Steve Daum
Capability analysis is a set of calculations used to assess whether a system is able to meet a set of requirements. Customers, engineers, or managers usually set the requirements, which can be specifications, goals, aims, or standards.
The primary reason for doing a capability analysis is to…
Donald J. Wheeler
Who can be against apple pie, motherhood, or good measurements? This is why everyone stands up and salutes when we are told to maintain our measurement systems in good calibration. But what is good calibration? By what method will we achieve it? And how will we know when we have it?
One day I…
Stanford News Service
Most leadership advice is based on anecdotal observation and basic common sense. Stanford Graduate School of Business professor Kathryn Shaw tried a different tack: data-driven analysis.
Through research done in collaboration with a very large, undisclosed technology-based company that has a…
Davis Balestracci
Have you ever heard something like: “I’m committed to Dr. Deming’s approach [or Six Sigma or lean or TPS, it doesn’t matter], but executives don’t seem to listen anymore. All they do is keep interrupting my very clear explanations with, ‘Show me some results, then show me what to do.’ I was…
Donald J. Wheeler
Now we come to the sixth way to use a process behavior chart. Here we are going to look at how one group of workers used their average and range chart to improve their process. Their part had only one critical dimension, and this dimension had a standard deviation of only 15 microns. What kind of…
Joby George
Having difficulty managing quality and quality-related data? You’re not alone. Many manufacturers struggle with this these issues due to paper-based or other disparate systems being used to track, manage, and report on quality events. Walk about a production room floor, and there’s a good chance…
Eston Martz
At last month’s Minitab Insights conference, experts from a wide range of industries offered some great lessons about how they use data analysis to improve business practices and solve a variety of problems. I shared five tips from quality leaders in yesterday’s column; here are five more.…
Eston Martz
If you were among the 300 people who attended the first-ever Minitab Insights conference last month, you already know how powerful it was. Attendees learned how practitioners from a wide range of industries use data analysis to address a variety of problems, find solutions, and improve business…
Scott A. Hindle
In all walks of life, being wrong can come with a penalty. It’s also true that, if you’re lucky, you sometimes get away with it without anybody being the wiser. To understand what this means in relation to the capability indexes Cp and Cpk, read on.
Introduction
In part 3 of “Process Capability:…
Davis Balestracci
Client A came to me for a consultation and told me upfront his manager would allow him to run only 12 experiments. I asked for his objective. When I informed him that it would take more than 300 experiments to test his objective, he replied, “All right, I’ll run 20.”
Sigh. No, he needed either to…
Fred Schenkelberg
We establish reliability goals and measure reliability performance. Goals and measures can be related; however, they’re not the same, and neither do they serve the same purpose.
Recently, I’ve seen a few statements that seem to confuse the role of statistical confidence when establishing a goal.…
Donald J. Wheeler
While we may tweak things in production, we rarely get permission to conduct formal experiments with an operating production line. Production’s job is to make product, whereas experiments are what they do in R&D. So how can we learn about an existing production process without rocking the boat…
Bruno Scibilia
There may be huge potential benefits waiting in the data in your servers. These data may be used for many different purposes. Better data allow better decisions, of course. For instance, banks, insurance firms, and telecom companies already own a large amount of data about their customers. These…
Davis Balestracci
Referring back to June’s column, I hope you’ve found C. M. Hendrix’s “ways to mess up an experiment” helpful in putting your design of experiments training into a much better perspective. Today, I’m going to add two common mess-ups from my consulting experience. If you’re not careful, it’s all too…
Eston Martz
A recent post at Ben Orlin’s always amusing mathwithbaddrawings.com blog nicely encapsulates why so many people feel wary about anything related to statistics and data analysis. Take a moment to check it out; it’s a fast read.
In all the scenarios Orlin offers in his post, the statistical…
Donald J. Wheeler
The question “Is this batch like the others?” is asked all over the world on a daily basis. It turns out that the process behavior chart provides a very effective answer for questions about the homogeneity of the product stream.
In World War II, Gen. Leslie Simon used the process behavior chart…
Scott A. Hindle
A t the end of part three of this four-part series on process capability, Alan was ready to identify a contact at the factory who could assist in providing some context around the collected data and the overall production process.
Discussion with Joe
Joe, working on the production team, was the…
Scott A. Hindle
Part two of this four-part series on process capability concluded with Alan just about to meet Sarah for a second time. He thought he was making good progress with his analysis of Product 874 data until he was asked to assess process capability, even though it can’t be assessed for an unstable…
Scott A. Hindle
In part one of this four-part series, we considered the basics of process capability, as witnessed through the learning curve of Alan in his quest to determine the product characteristics of the powder, Product 874. We pick up with Alan here as he prepares for his second meeting with his colleague…
Scott A. Hindle
In my August 2015 article, “Process Capability: How Many Data?” I discussed whether 30 data were the “right” number in an analysis of process capability. In this four-part series, the focus is on understanding what process capability is and the pitfalls associated with it, along with how it can…
Davis Balestracci
I hope this little diversion into design of experiments (DOE) that I’ve explored in my last few columns has helped clarify some things that may have been confusing. Even if you don’t use DOE, there are still some good lessons about understanding the ever-present, insidious, lurking cloud of…
Meredith Griffith
When I wrote about automation back in March, I made my husband out to be an automation guru. He certainly is, but what you don’t know about my husband is that, although he loves to automate everything in his life, sometimes he drops the ball. He’s human. On the other hand, instances of hypocrisy…
