* TAGUCHI'S DEFINITION OF QUALITY
* TAGUCHI'S LOSS FUNCTION
* TAGUCHI, ROBUST DESIGN, AND THE DESIGN OF EXPERIMENTS
* EXAMPLES AND CONCLUSIONS
* FURTHER READING:
There has been a great deal of controversy about Genichi Taguchi's methodology since it was first introduced in the United States. This controversy has lessened considerably in recent years due to modifications and extensions of his methodology. The main controversy, however, is still about Taguchi's statistical methods, not about his philosophical concepts concerning quality or robust design. Furthermore, it is generally accepted that Taguchi's philosophy has promoted, on a worldwide scale, the design of experiments for quality improvement upstream, or at the product and process design stage.
Taguchi's philosophy and methods support, and are consistent with, the Japanese quality controlapproach that asserts that higher quality generally results in lower cost. This is in contrast to the widely prevailing view in the United States that asserts that quality improvement is associated with higher cost. Furthermore, Taguchi's philosophy and methods support the Japanese approach to move quality improvement upstream. Taguchi's methods help design engineers build quality into products and processes. As George Box, Soren Bisgaard, and Conrad Fung observed: "Today the ultimate goal of quality improvement is to design quality into every product and process and to follow up at every stage from design to final manufacture and sale. An important element is the extensive and innovative use of statistically designed experiments."
TAGUCHI'S DEFINITION OF QUALITY
The old traditional definition of quality states quality is conformance to specifications. This definition was expanded by Joseph M. Juran (1904-) in 1974 and then by the American Society for Quality Control (ASQC) in 1983. Juran observed that "quality is fitness for use." The ASQC...