How Many Samples Do You Need to Be Confident Your Product Is Good?
How many samples do you need to be “95% confident that at least 95%—or even 99%—of your product is good?The answer depends on the type of response variable you are using, categorical or continuous. The...
View ArticleSealing Up Patient Safety with Monte Carlo Simulation
If you have a process that isn’t meeting specifications, using the Monte Carlo simulation and optimization tools in Companion by Minitab can help. Here’s how you, as an engineer in the medical device...
View ArticlePoisson Data: Examining the Number Deaths in an Episode of Game of Thrones
There may not be a situation more perilous than being a character on Game of Thrones. Warden of the North, Hand of the King, and apparent protagonist of the entire series? Off with your head before the...
View ArticleArea Graphs: An Underutilized Tool
In my time at Minitab, I’ve gotten a good understanding of what types of graphs users create. Everyone knows about histograms, bar charts, and time series plots. Even relatively less familiar plots...
View ArticleHow to Eliminate False Alarms on P and U Control Charts
All processes have variation, some of which is inherent in the process, and isn't a reason for concern. But when processes show unusual variation, it may indicate a change or a "special cause" that...
View ArticleSunny Day for A Statistician and A Householder – An Update
We had solar panels fitted on our property in 2011. Last year, we had a few problems with the equipment. It was shutting down at various times throughout the day, typically when it was very sunny,...
View Article3 Keys to Getting Reliable Data
Can you trust your data? That's the very first question we need to ask when we perform a statistical analysis. If the data's no good, it doesn't matter what statistical methods we employ, nor how much...
View ArticleHow to Estimate the Probability of a No-Show using Binary Logistic Regression
In April 2017, overbooking of flight seats hit the headlines when a United Airlines customer was dragged off a flight. A TED talk by Nina Klietsch gives a good, but simplistic explanation of why...
View Article5 Critical Six Sigma Tools: A Quick Guide
Six Sigma is a quality improvement method that businesses have used for decades—because it gets results. A Six Sigma project follows a clearly defined series of steps, and companies in every industry...
View Article5 More Critical Six Sigma Tools: A Quick Guide
The Six Sigma quality improvement methodology has lasted for decades because it gets results. Companies in every country around the world, and in every industry, have used this logical, step-by-step...
View ArticleFlight of the Chickens: A Statistical Bedtime Story, Part 1
by Matthew Barsalou, guest bloggerOnce upon a time, in the Kingdom of Wetzlar, there was a farm with over a thousand chickens, two pigs, and a cow. The chickens were well treated, but a few...
View ArticleFlight of the Chickens: A Statistical Bedtime Story, Part 2
by Matthew Barsalou, guest bloggerAt the end of the first part of this story, a group of evil trouble-making chickens had convinced all of their fellow chickens to march on the walled city of Wetzlar,...
View ArticleWhat's the Difference between Confidence, Prediction, and Tolerance Intervals?
In statistics, as in life, absolute certainty is rare. That's why statisticians often can't provide a result that is as specific as we might like; instead, they provide the results of an analysis as a...
View ArticleControls Charts Are Good for So Much More than SPC!
Control charts take data about your process and plot it so you can distinguish between common-cause and special-cause variation. Knowing the difference is important because it permits you to address...
View ArticleThe Easiest Way to Do Multiple Regression Analysis
Maybe you're just getting started with analyzing data. Maybe you're reasonably knowledgeable about statistics, but it's been a long time since you did a particular analysis and you feel a little bit...
View ArticleHow to Avoid Overfitting Your Regression Model
Overfitting a model is a real problem you need to beware of when performing regression analysis. An overfit model result in misleading regression coefficients, p-values, and R-squared statistics....
View Article3 Ways to Gain Buy-In for Continuous Improvement
Research out of the Juran Institute, which specializes in training, certification, and consulting on quality management globally, reveals that only 30 percent of improvement initiatives succeed. And...
View ArticleFighting Wildfires with Statistical Analysis
Wildfires in California have killed at least 40 people and burned more than 217,000 acres in the past few weeks. Nearly 8,000 firefighters are trying to contain the blazes with the aid of more than 800...
View ArticleUsing Data to Save Lives: Q&A on Quality Improvement in Healthcare
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View ArticleWHO Cares about How Much Sugar You Eat on Halloween?
Are you going to be a witch today? Batman? Jedi? You're not alone according to National Retail Federation statistics on top costumes and Halloween spending trends. Last-minute candy shopping? Check out...
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