Centroid-Point of Ranking Fuzzy Numbers and Its Application to Health Related Quality of Life Indicators

Ranking of fuzzy numbers is not an easy task as fuzzy numbers are represented by possibility distributions and they can overlap with each other. Since it was introduced, various approaches on ranking fuzzy numbers have been proposed. The recent ranking fuzzy numbers proposed by Wang and Li is claimed to be the improved version in ranking. However, the method was never been simplified and tested in real life application. This paper presents a four-step computation of ranking fuzzy numbers and its application in ranking indicators of health related quality of life. The four steps algorithm was proposed as to establish ranking and followed by a testimony in health related symptoms among elderly. Data in form of linguistic terms were collected from three experts at State of Terengganu Malaysia. Decisions were made based on the centroid-point ( y x, ), where the degree of representative location ( x ) is higher than average height ( y ). These points permit to characterize the evaluation behaviour of each indicator. The ranking reflects the problematic level of elderly people. The results show the feasibility of the proposed stepwise computation in real application. KeywordsCentroid-points, fuzzy numbers, ranking, health related indicator