The Coefficient Determination of Multivariate Quality Loss Model

The quality loss model was proposed by Genichi Taguchi in the early 1970s, and it was the core of his three-stage design theory, system design, parameter design and tolerance design. The quality loss model was based on one index of absolute quality deviants. However, in actual production process, the total quality is usually influenced by several quality indices, so the interaction of the quality indices should be considered. First, a 2-order product quality model, which was based on several indices of relatively quality deviation, was built. Then, the model was successfully extended to 3 or even higher orders. After this, the 2-order mode was simplified to build a multivariate quality loss model. Finally, a useful method of the coefficient determination was brought forward to determinate all the coefficients in the multivariate quality loss model and the workflow of it was also described.