TABLE OF CONTENTS Dr. Genichi Taguchi is a well-known Japanese quality expert who pioneered the idea of robust engineering (Taguchi and Wu, 1979; Taguchi, 1993). The robust engineering method is a comprehensive quality strategy that builds robustness into a product/process during its design stage. Robust engineering is a combination of engineering design principles and Taguchi s version of design of experiments, which are called orthogonal array experiments. Taguchi and coworkers [Taguchi (1981), Taguchi, Elsayed, and Hsiang (1989)] also developed a system of online quality control methods, which is featured by quality loss function and Taguchi tolerance design. The system of robust engineering, Taguchi online quality control methods, and other methods developed by Taguchi are usually called the Taguchi method.
The recent addition to the Taguchi method is the Mahalanobis-Taguchi system (MTS). (Taguchi et al., 2001; Taguchi and Jugulum, 2002). The Mahalanobis-Taguchi system is a multivariate data-based pattern recognition and diagnosis system. A significant number of case studies have been recorded, based on the MTS, which range from health diagnosis, electronic manufacturing, chemical industry, fire prevention, etc. There are more than 70 published case applications in a wide variety of companies such as Nissan, Fuji, Xerox, Ford, Sony, Delphi, Yamaha, Minolta, Konica, and several medical firms.
In this approach, a large number of multivariate data sets are collected, and then the data sets for healthy or normal groups are partitioned from other data sets for abnormal or unhealthy groups. For example, in liver disease diagnosis, for each potential patient, many kinds of medical...
