What Does It Mean When Your Probability Plot Has Clusters?
Have you ever had a probability plot that looks like this?The probability plot above is based on patient weight (in pounds) after surgery minus patient weight (again, in pounds) before surgery.The red...
View ArticleHow Cpk and Ppk Are Calculated, part 1
In technical support, we frequently receive calls from Minitab users who have questions about the differences between Cpk and Ppk. Michelle Paret already wrote a great post about the differences...
View ArticleHow Cpk and Ppk Are Calculated, part 2
Minitab's capability analysis output gives you estimates of the capability indices Ppk and Cpk, and we receive many questions about the difference between them. Some of my colleagues have taken other...
View ArticleThe World-Famous Disappearing-Reappearing-Analysis-Settings Act
Sure, Minitab Statistical Software is powerful and easy to use, but did you know that it’s also magic? One of the illusions that Minitab can peform is the world famous...
View ArticleWhich Is Better, Stepwise Regression or Best Subsets Regression?
Stepwise regression and best subsets regression are both automatic tools that help you identify useful predictors during the exploratory stages of model building for linear regression. These two...
View ArticleAnalyzing the Final College Football Playoff Poll
Throughout the college football season, I’ve been looking at the influence of the preseason AP Poll on rankings later in the season. Each analysis found a positive association between preseason...
View ArticleHow to Calculate B10 Life with Statistical Software
Over the last year or so I’ve heard a lot of people asking, “How can I calculate B10 life in Minitab?” Despite being a statistician and industrial engineer (mind you, one who has never been in the...
View ArticleAn Unauthorized Biography of the Stem-And-Leaf Plot - Part II: A New Leaf
At the end of my previous post, aspiring statisticians Woodrow "Woody" Stem and August "Russell" Leaf, creators of the famed Stem-and-Leaf plot, were in bad shape. They had beaten each other statsless...
View ArticleUnderstanding Qualitative, Quantitative, Attribute, Discrete, and Continuous...
"Data! Data! Data! I can't make bricks without clay." — Sherlock Holmes, in Arthur Conan Doyle's The Adventure of the Copper BeechesWhether you're the world's greatest detective trying to crack a case...
View ArticleA Minitab Holiday Tale: Featuring the Two Sample t-Test
by Matthew Barsalou, guest bloggerAaron and Billy are two very competitive—and not always well-behaved—eight-year-old twin brothers. They constantly strive to outdo each other, no matter what the...
View Article3 Things a Histogram Can Tell You
Histograms are one of the most common graphs used to display numeric data. Anyone who takes a statistics course is likely to learn about the histogram, and for good reason: histograms are easy to...
View ArticlePoisson Processes and Probability of Poop
On a recent vacation, I was unsuccessfully trying to reunite with my family outside a busy shopping mall and starting to get a little stressed. I was on a crowded sidewalk, in a busy city known for...
View Article3 Ways Minitab Can Illustrate My Ignorance about British Honours
I like learning about new things. This fondness makes it less depressing when I have to admit total ignorance on any subject. Thus, when I heard that there were “New Year honours” given out, I expected...
View ArticleCan a Statistician Say that Age Is Just a Number?
Last fall I had a birthday. It wasn’t one of those tougher birthdays where the number ends in a zero. Still, the birthday got me thinking. In response, I told myself, age is just a number. Then I did a...
View ArticleControl Your Control Chart!
As a member of Minitab's Technical Support team, I get the opportunity to work with many people creating control charts. They know the importance of monitoring their processes with control charts, but...
View ArticleBirds Versus Statisticians: Testing the Gambler's Fallacy
by Matthew Barsalou, guest bloggerRecently Minitab’s Joel Smith posted a blog about an incident in which he was pooped on by a bird. Twice. I suspect many people would assume the odds of it happening...
View ArticleTom Brady and the Danger of Selective Endpoints
Last Friday I had an interesting tweet come across my Twitter feed.And that was before the Patriots failed to cover their first playoff game of 2015 against the Ravens. When you include that, the...
View ArticleHow to Talk to Your Kids about Quality Engineering, Part 2: Statistical...
I really can’t make this stuff up.I wrote a post a couple of years ago entitled: “How to Talk to Your Kids about Six Sigma and Quality Improvement,” in which I lamented about “Community Hero” day in my...
View ArticleReducing the Size of Your General Full Factorial Design
You may have been in a situation where you had created a general full factorial design and noticed that your design’s run size was higher than you imagined. (Quick refresher: a general full factorial...
View ArticlePlot the State of the Union Global Temperature Data in Minitab
In the State of the Union Address, President Obama said:“No challenge — no challenge — poses a greater threat to future generations than climate change. 2014 was the planet’s warmest year on record....
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