Using fuzzy method to measure the consistency of service quality

Service quality is very important for practitioners in service organization in order to success and survival in today´s competitive environment. Indentifying the dimensions of the service quality would definitely help managers in the challenge of improving the service quality. Service-quality evaluation is usually fuzzy because of the process concerning human being´s subjective judgment. This study presents an evaluation approach to evaluate the consistency of service quality problem with fuzzy numbers. Based on the probability of fuzzy sets defined by Zadeh [1], the membership function of triangular fuzzy number determined by each customer with respect to each evaluation-item is first calculated, the coefficient of variation is calculated, and the degree of service consistency for each evaluation-item can then be recognized. Those data can be the bases when making strategies of improving service quality. An empirical study is conducted to illustrate the effectiveness of the presented approach.