Using a modified grey relation method for improving airline service quality

This study applies a modified grey relation method to improve service quality among domestic airlines in Taiwan. First, we replace the referential alternative (sequence) with an aspired alternative, which should better reflect the reality of today’s competitive markets. Second, because the compared alternatives do not usually have the same criteria/aspects, traditional methods are unsuitable to deal with them. Our model fixes this problem, allowing decision-makers to understand the gaps between alternatives and aspired levels in practice. Third, we develop a new ranking index to measure the airlines’ competitiveness in terms of service quality. To validate the effectiveness of our model, we conduct a large sample survey. We also provide managerial improvements needed by each carrier to achieve the aspired level of customer satisfaction.