Using fuzzy numbers to evaluate perceived service quality

A new method of measuring perceived service quality based on triangular fuzzy numbers is proposed in this paper. It avoids using difference scores (perceptions minus expectations) which were applied by many marketing researchers but were criticized by Brown et al. (J. Retailing 69 (1) (1993) 127-139). From consumers' standpoints, we replace perceptions by satisfaction degree as well as expectations by importance degree. To evaluate the discrepancy between consumers' satisfaction degree and importance degree, we induce general solutions to compute the intersection area between two triangular fuzzy numbers, then the weak and/or strong attributes of retail stores are clarified. Our method overcomes linguistic problems, and the case study provides more objective information for retail industry in Taiwan. In addition, the method is comparable with Dubois's method, which is based on possibility theory. (C) 2000 Elsevier Science B.V. All rights reserved.