Genichi Taguchi

was a Japanese engineer and statistician. From the 1950s on, Taguchi developed a methodology for applying statistics to improve the quality of manufactured goods. Taguchi methods have been controversial among some conventional Western statisticians, but others have accepted many of the concepts introduced by him as valid extensions to the body of knowledge.

Biography

Taguchi was born and raised in the textile town of Tokamachi, in Niigata prefecture. He initially studied textile engineering at Kiryu Technical College with the intention of entering the family kimono business. However, with the escalation of World War II in 1942, he was drafted into the Astronomical Department of the Navigation Institute of the Imperial Japanese Navy.

After the war, in 1948 he joined the Ministry of Public Health and Welfare, where he came under the influence of eminent statistician Matosaburo Masuyama, who kindled his interest in the design of experiments. He also worked at the Institute of Statistical Mathematics during this time, While working at the SQC Unit of ISI, he was introduced to the orthogonal arrays invented by C. R. Rao - a topic which was to be instrumental in enabling him to develop the foundation blocks of what is now known as Taguchi methods.

On completing his doctorate at Kyushu University in 1962, he left ECL, though he maintained a consulting relationship. In the same year he visited Princeton University under the sponsorship of John Tukey, who arranged a spell at Bell Labs, his old ECL rivals. In 1964 he became professor of engineering at Aoyama Gakuin University, Tokyo. His concepts pertaining to experimental design, the loss function, robust design, and the reduction of variation have influenced fields beyond product design and manufacturing, such as sales process engineering.

Taguchi Approach to Robust Design One of Genichi Taguchi’s most important contributions was the development of the concept of robust design, which aims to minimize product variability even under adverse conditions. This approach is based on the use of orthogonal arrays and the signal-to-noise (S/N) ratio analysis, with the goal of optimizing products and processes at early stages of design. The Taguchi method has been widely adopted in the automotive and electronics industries due to its effectiveness in reducing costs and improving quality.

Contributions

Taguchi has made a very influential contribution to industrial statistics. Key elements of his quality philosophy include the following: Taguchi loss function, used to measure financial loss to society resulting from poor quality; The philosophy of off-line quality control, designing products and processes so that they are insensitive ("robust") to parameters outside the design engineer's control. Innovations in the statistical design of experiments, notably the use of an outer array for factors that are uncontrollable in real life, but are systematically varied in the experiment.

Honours

1960 - Deming Prize for Individuals 1986 - Willard F. Rockwell Medal of the International Technology Institute 1989 - Indigo Ribbon from the Emperor of Japan 1990 - Honoured as a Quality Guru by the British Department of Trade and Industry 1995 - Honorary member of the Japanese Society of Quality Control 1996 - Honorary Fellow of the Institute of Directors (India) 1997 - Automotive Hall of Fame Inductee 1998 - Honorary member of the American Society for Quality 1998 - Honorary member of the American Society of Mechanical Engineers 1999 - Honorary president of the Robust Quality Engineering Society (Japan)

Books