I had a lot of feedback from interested readers in regards to Stupid Six Sigma Tricks #5, which I jokingly called “Pop Stars Without Clothing,” and which was about the frequent misuse of statistics in the Six Sigma world. Taking heart from this response to what might have been viewed as dusty old statistics, I decided forthrightly to call this Stupid Six Sigma Trick #3, Prurient Photographs. Oh, all right, it’s not really about that either. I thought I’d continue my riff on the bad statistics that I run across frequently, so this is really SSST #3, The Bride of Bad Stats.

Now remember, I’m just a lowly engineer who views statistics as a way to get things done efficiently and economically. I can appreciate the staggering beauty of a complex statistical analysis, but when it helps solve a problem or make some money for a company, that’s when I get really interested. So, the issues I’m going to bring up are ones that not only happen frequently with Black Belts, but also end up costing companies money either through missed opportunities or incorrect conclusions. This isn’t to say that these are the only statistical errors costing Six Sigma companies money—just that these are the only ones I want to write about now.

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