Improvement Insights Blog
Is Fear of Math Holding You Back?
Many people avoid Six Sigma because they think it involves a lot of math and statistics. You know, formulas. I don’t think you need any formulas. You don’t need to be a statistician. You just need software that went to college and knows the formulas.
In The Math Gene, Author Keith Devlin explores “why so many people find mathematics impossibly hard.” He says: mathematics is the science of patterns. Isn’t that what we’re trying to do in Six Sigma, separate the wheat from the chaff, separate the signal from the noise and detect the underlying patterns of performance?
Devlin also differentiates between arithmetic and mathematics. He argues that our brains aren’t well designed for arithmetic, but we are all good a math. My wife, for example, is dyslexic when it comes to numbers. Give her a phone number and she will often transpose numbers (arithmetic). But she can write software that involves algorithms (math).
Devlin also says that mathematics help make the invisible, visible. Again, isn’t that what we’re trying to do with Six Sigma? That’s why I always talk about the invisible low hanging fruit. You can’t see it, but it’s there.
Devlin’s metaphor of math is interesting; it’s construction: “Learning new mathematics is like constructing a mental house in my mind. Understanding new mathematics is like exploring the interior of the house. Working a math problem is like rearranging the furniture. Thinking mathematics is like living in the house.”
Devlin lists the following mental attributes as key to mathematical ability:
- A number sense (1, 2, 3)
- Numerical ability
- Algorithmic ability
- Abstraction
- Cause and effect (e.g., root cause analysis)
- The ability to construct and follow a causal chain of facts or events (e.g., an improvement project)
- Logical reasoning ability
- Relational reasoning ability
- Spatial reasoning ability (e.g., spaghetti diagram)
Notice, he never says formulas.
Implications for Six Sigma
In Six Sigma, we can let QI Macros calculate the formulas and give us control charts, Pareto charts and histograms that show the underlying patterns of performance. Then we can do some root cause analysis to find and fix those performance problems.
I realize that most Six Sigma books and courses are filled with formulas and manual calculations, but all that does is traumatize students and waste time. You don’t need to know formulas to do Six Sigma, but you do need to understand the patterns revealed in the charts.
Why do Six Sigma books and course insist that everyone learn the formulas behind the charts and statistics? Here’s my short answers: Because it fills up the curriculum (I get paid more if I teach longer). Because that’s how I learned it (I went through this hell; so should you). Because you need it to get by (no you don’t).
I want to make Six Sigma edible by the masses. Devlin says: “What a few individuals may be trained to do doesn’t matter. Only what an entire species does easily, naturally and by inclination is significant.”
Stop worrying about formulas. Start drawing control charts, Pareto charts and histograms that illustrate the underlying patterns of performance. Then start moving those charts in the right direction—fewer defects and less variation. That’s all you need to know to succeed a Six Sigma.
