Episode Details

What is the Taguchi Loss Function and how does it apply to education? In this episode, Andrew and David talk about statistician Genichi Taguchi's idea that the further you move from a measurable quality target, the more quality is lost, even if the item still "meets specifications." David shows how you can apply this to education.

(For more about the Tachugi Loss Function, visit Wikipedia or Christopher Chapman's Digestible Deming blog post.)

TRANSCRIPT

Stotz: My name is Andrew Stotz, and I'll be your host as we continue our journey into the teachings of Dr. W Edwards Deming. Today, I'm continuing my discussion with David P. Langford, who has devoted his life to applying Dr. Deming's philosophy to education, and he offers us his practical advice for implementation. Today's topic is, Taguchi loss function. David, take it away.

Langford: Thank you, Andrew. And I liked how your eyes got really big when you said Taguchi loss function. Oh my gosh, it sounds frightening, doesn't it?

Stotz: It does. It's a little bit overwhelming, it's exciting. I'm interested to learn.

Langford: And in education, it's probably less known than it is in business. Usually when I'm working with a group of business leaders and I mention that I can get pretty strong - two-thirds of the audience probably knows something about the Taguchi loss function. I was at a conference with a whole roomful of school superintendents and I asked them, Anybody know what the Taguchi loss function was? And not a single hand went up. So less well known, but just as applicable. So in one of the earlier podcasts, we were talking about the concept of optimization of the system. And I just wanna refresh our memories and the memory of our listeners that it's really based on Deming's System of Profound Knowledge as well. So the four parts that Deming had was, Appreciation for a System, Understanding Variation, and especially statistical variation, Psychology and Knowledge of Theory. And I always add neuroscience to that mix as part of profound knowledge, because it's really critical to understand, especially in education, how the brain actually processes information.

Langford: So when we're talking about the optimization of a system, we're actually talking about all of those factors being optimized, especially in a classroom or a school. So you can't just sort of optimize one thing, for instance. So over the last 30 years, I've known principals that are just really, really good managers, excellent at running the building. They never do anything out of the ordinary, everything is always perfect. The trash cans are always where they're supposed to be. They're just really good managers. They're the kind of people that if you're gonna take a school trip and they have to organize something complex, that's the kind of people you want. But if you're gonna do something really super innovative, change the system in some way, do something that's never been done before, that's not the kind of person that you want.

Stotz: Right, it's interesting that you just mentioned that optimizing so many different factors, that's part of the reason why people don't do it because it is complex. David, I just pulled up Wikipedia and I thought maybe it would be interesting if we see what Wikipedia says about what is the Taguchi loss function. Would you like me to read a little bit of that?

Langford: Yeah, so, go ahead.

Stotz: According to Wikipedia, the Taguchi loss function is graphical depiction of loss developed by the Japanese business statistician, Genuichi Taguchi to describe a phenomenon affecting the value of products p