Buzz words in job requirement - Taguchi method

The first time I heard "Taguchi method" is in the six sigma course. It's not covered by the intense course. But the professor did mention it several times.

I kept on searching for details about the method. It seems not well defined even in Wikipedia. Maybe the term itself is not clear or accurate. The exact term might be "Taguchi method in design of experiments". If that is the case, I think "Taguchi method" is just orthogonal analysis in fractal factorial design.

the Idea
In simple English. "Taguchi method" is the method to use smallest runs of experiment, which neglects effect of combination of factors.

If effect of combination of factors is not our interest, we can use 8 runs of experiment to represent an experiment with up to 7 facors, which is far more effective than full factorial case, 2⁷=128

Design of experiment
I'm not sure if should use this as a heading. It covers lots of topics and Fisher even wrote a book about it in 1935. Here I will copy the rule of thumbs about options in design of experiments from one online document
as the summary of this blog.

When do we use which method?

• Option 1: Factorial Design
• Small numbers of variables with few states (1 to 3)
• Interactions between variables are strong and important
• Every variable contributes significantly
• Option 2: Taguchi Method
• Intermediate numbers of variables (3 to 50)
• Few interactions between variables
• Only a few variables contributes significantly
• Option 3: Random Design
• Many variables (50+)
• Few interactions between variables
• Very few variables contributes significantly