This is a reply to the comments on the previously published paper entitled “Using a modified grey relation method for improving airline service quality”. The commentators question that the paper does not offer any improvement over Chen and Tzeng’s (2004) work and uses the same data as in Liou, Tsai, Lin, and Tzeng’s (2011b) paper. However, the modified grey relation described therein actually does improve on Chen and Tzeng’s (2004) work in two ways. First, the ideal and negative ideal referential sequences are replaced by the aspired to and tolerable levels. Second, the similarity used in the grey relation model is transformed into a weighted gap, “the smaller the better”. The same survey data is used in both papers, but the targets and purposes differ. One is focused on economy class passengers, while the other targets all passengers. Therefore, we argue that the comments indicate misunderstanding of the modifications.
