Category Archives: Six Sigma

Transforming Non-normal Data: Proceed with Caution!

Data that follow a distribution that is either not symmetric or that is symmetric but not bell shaped are said to be non-normal.   A common misconception among students is that all data should be normally distributed, and that there is something inherently wrong if their data is not normally distributed.  In fact, data is not […]

A Real World Application of Design of Experiments

Black Belt students are exposed to Design of Experiments (DOE) in their classroom training, but in my experience very few of them actually apply the technique while completing a project to earn their Black Belt certificate.  One of my students recently completed a project that made excellent use of a Designed Experiment, and his company […]

Writing an Operational Definition for a Measure

Our Yellow Belt course includes an assignment where students are required to write an operational definition for measuring something.  An operational definition, when applied to data collection, is a clear, concise and detailed definition of a measure. The need for operational definitions is fundamental when collecting all types of data. Here is the text of […]

Statistical Software – a Trap for the Unwary

In our Six Sigma courses we make extensive use of Minitab statistical software.  Minitab is an extremely comprehensive and powerful software package.  At the same time author Milton Rosenau provided this caution when he said “(Software)…is also a trap for the unwary.” When evaluating the output of a piece of software such as Minitab, we […]

Quality Pioneers – The Evolution of Six Sigma – Fourth in a Series

One of the first assignments in our Black Belt course deals with the origins of the continuous improvement approach that we know today as Six Sigma.  Many students are surprised to learn that the body of knowledge and the tools and techniques have been evolving for well over 100 years. This article is the fourth […]

Quality Pioneers – The Evolution of Six Sigma – Third in a series

One of the first assignments in our Black Belt course deals with the origins of the continuous improvement approach that we know today as Six Sigma.  Many students are surprised to learn that the body of knowledge and the tools and techniques have been evolving for well over 100 years. This article is the third […]

Quality Pioneers – the Evolution of Six Sigma – second in a series

One of the first assignments in our Black Belt course deals with the origins of the continuous improvement approach that we know today as Six Sigma.  Many students are surprised to learn that the body of knowledge and the tools and techniques have been evolving for well over 100 years. This article is the second […]