Classification of water quality using interval TOPSIS method

In this paper, Multi-Criteria Decision Making (MCDM) approach called Interval-TOPSIS (Technique for Order Preference by Similarity to Ideal Solution) has been introduced to assess the effectiveness of choice alternatives based on a number of criteria. It modifies the conventional TOPSIS approach to handle interval-valued data, which conveys that the criterion values are expressed as range instead of single numbers. Relative closeness coefficients have been determined in this present approach. According to the values of the closeness coefficients, the alternatives can be ranked and the most desirable one(s) can be selected in the decision-making process. In this paper, the best water quality among 5 sets of water has been found, using the proposed Interval-TOPSIS approach and then the results are compared to conventional TOPSIS and SAW approach.