Problems and Issues with Control Charts

Statistical process control charts, aka Shewhart control charts, are introduced in our Green Belt course.  At the Black Belt level, students are tasked to develop control charts for the primary Y variable that is to be the focus of improvement during the Define phase of their Black Belt project. Before we can rely on the […] read more

On August 11th, 2017, posted in: Articles, Six Sigma by Tags:

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 […] read more

On August 2nd, 2017, posted in: Articles, Six Sigma by Tags: ,

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 […] read more

On July 14th, 2017, posted in: Articles, Six Sigma by Tags: , ,

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 […] read more

On June 4th, 2017, posted in: Articles, Six Sigma by Tags: ,