A New Consensus-based Fuzzy Group Decision-Making Algorithm Case Study: Groundwater Resource Management

Decision-making is an essential process in many financial, engineering, and medical fields. Multi Criteria Decision Making (MCDM) and Group Decision-Making (GDM) are among well practiced approaches in solving decision making problems. Group Decision-Making basically combines professional judgments into a coherent group decision. This paper surveys Fuzzy Group Decision Making (FGDM) and develops a new consensus-based fuzzy group decision making algorithm. Decision Makers (DMs) may express their opinions about alternatives and importance of each criterion in four different formats as follow: (1) preference ordering, (2) utility values, (3) fuzzy preference relations; and (4) multiplicative preference relations. In this proposed algorithm, unifying the evaluations of each expert, results in an aggregated score for each alternative. The third step is to rank the linguistic labels or fuzzy sets and select the preferred alternatives based on this sorting. Finally, the decision manager assesses the consensus level and the individual contribution to the group decision and selects the final solution. To illustrate the application of the model in the real decision making processes, this algorithm is used to a groundwater development project to select the most preference alternative for a regional water supply system. Results indicate that the proposed Fuzzy Group Decision Making approach is a relevant approach to aggregate the individual expert’s opinion in order to reach a reasonable and determinate consensus level among DMs.