Y = f(X)

Another way to recognize a Lean Six Sigma program that has “dumbed” it down can be found in the y=f(x). Every program talks about it as a concept, but they fail to really tell you how to do it. If you come into it with a strong math or statistics background you can figure it out, but what about everyone else. Top programs give you the skills to mix continuous and attribute data into a single equation. The mid range programs show you how to mix a set of continuous factors or a set of attribute factors, but not a mixture.

If you use Minitab, I will share some of the tricks to combine continuous and attribute data into a single model that will predict the results.

If they are mostly continuous factors with a few attributes: Use the “Calc>make indicator variable” function to map the attribute into columns of zeros and ones. Now use Stat>Regression>Regression function with the continuous factors and all but one of the indicator columns.

If they are mostly attributes with a few continuous factors: Use the Stat>ANOVA>General Linear Model function. All the attributes go into the model while the continuous factors are assigned with the Covariate Option button. You also need to adjust the output options to include coefficients.

Both methods will provide you the coefficients to build a true Y=F(X) equation.

Of course without these two statistical methods, you can still predict the output using a simulation program and your process map knowledge.

Good Luck

These methods can be found in “Integrated Enterprise Excellence Volume III” by Forrest Breyfogle in the ANOVA and Regression chapters.