Application of Fuzzy Relative Quality Performance Matrix on the Improvement of Critical to Quality Problems

The implementation of 6-sigma project consists of five well-known stages, that is, define, measure, analyze, improve and control. Among them, four have received much analysis and exploration by articles and scholars as well. While in the respect of definition, quite a few literatures have suggested that voice of customer (VOC) should be used as the core basis in improving the overall business performance. In collecting VOC, questionnaire has long been regarded as one of the most important tools. Whereas VOC is in nature fuzzy and non-quantitative, to which the mandatory dichotomy cannot seem to apply. To effectively collect genuine VOC, this paper tries to adopt fuzzy linguistic questionnaire (FLQ) instead of the conventional Likert-type scale. In presenting our definition of customerpsilas fuzzy valuation index and fuzzy satisfaction index, we have referred to the methods adopted by Y. H. Hung et al. (2003). Furthermore, a set of fuzzy relative quality performance matrix (FRQPM) will be suggested by combining relative competition matrix proposed by D. M. Lambert & A. Sharma (1990), to help businesses in defining, through objectively viewed VOC, CTQ problems, in the process of promoting the 6-sigma program.