A new weighting method for detecting outliers in IPA based on Choquet integral

When interactions among items of survey exist in importance-performance analysis (IPA), the traditional equal weighting method for detecting outliers in IPA is not always available. In this paper, we suggest to use Choquet integral based on two fuzzy measures, the well known fuzzy measures, lambda-measure, proposed by Sugeno, and gamma-measure, proposed by our previous study, to improve this situation. A real data experiment by comparing the numbers of reduced outliers and the changing numbers of items which were needed improvement was conducted. The performances of traditional equal weighting method, lambda- measure Choquet integral weighting method, and gamma-measure Choquet integral weighting method for detecting outliers in IPA were compared. Experimental result shows that the gamma- measure Choquet integral weighting method outperforms the other two weighting methods.