Comments on: What is Taguchi? How does it relate to testing?

By: Juan Rivas

Juan Rivas — Mon, 09 Jun 2008 19:51:21 +0000

This comments are erroneous in part, because Taguchi Methods are based on Plackett Burmann design, and Taguchi took this option for many interesting reasons.

The author of this article is an ignorant, because Taguchi Method is a philosophy , a little bit of Design of Experiments, in fact you can analyze a Design of Experiment from fractional factorial design classical through S/N ratios….in question to multivariate analysis you can work with MTGS also Taguchi Method.

By: Billy

Billy — Mon, 25 Feb 2008 22:43:32 +0000

Hi Dale,
It’s difficult to understand what you’re saying without having read Roy’s book. We are not saying that the Taguchi method has no standing or merit, just that by itself it is not the best method to decipher marketing data. The goals of the Taguchi method is far from what we, as marketers, are trying to achieve.

What you described as “adjustments” is close to what I am saying. The Taguchi method is a part of fractional factorial design, but is not all encompassing. Marketers that say they are using “the Taguchi method” probably are just doing fractional factorial design and incorrectly attributing it to the Taguchi method.

I just want to clarify that the true Taguchi method is not made for marketing and should not be sought as the answer to answer multivariate tests.

By: Dale Jelinek

Dale Jelinek — Thu, 21 Feb 2008 20:37:59 +0000

I am reading Ranjit Roy’s “Primer on the Taguchi Method” and I sense that his understanding differs from that of Vladimir in a few areas. Being a non-statistician and neophyte in this area I don’t claim to know the answers, but here is where I see the differences:

- “There is no possibility of detecting interactions among the control factors”
+ In Roy’s book he covers this topic in many sections, starting in Section 5-5-2 “Interaction Affects”. He also publishes Taguchi’s triangular tables and linear graphs which provide information on how to isolate interaction effects of the control factors in the orthogonal arrays.

- “However the confounding structure for the control factors is the same as that of an array of size N1. This implies that the same resolution can be obtained with much smaller number of runs. ”
+ The full factorial array is N1 * N2 in size, but isn’t that the point of the research done by Taguchi - that by using orthogonal fractional factorial arrays that you can use a fraction of the number of experimental runs to capture the essential information to determine main effects and interaction effects?

I have heard the comment in the past that the Taguchi approach does work in marketing, but there are “adjustments” that need to be made to make it useful in that context. Have you any idea what those “adjustments” might be?

Thank you in advance for your expanded comments in reply, I am looking forward to advancing my understanding of optimization techniques applied to marketing.

By: Terry Polyak

Terry Polyak — Wed, 20 Feb 2008 17:36:08 +0000

Nice article. I always wondered how auto manufacturing QC and website Optimization through MVT were related……only that it was a process to arrive to an end with mathematics helping you get to a result quicker. Zoom zoom.