Aggregation of fuzzy views of a large number of stakeholders for multi-objective flood management decision-making

Flood management decision-making problems are often associated with multiple objectives and multiple stakeholders. The challenge remains on how to obtain the diversified opinions of a large number of stakeholders where uncertainty plays a major role. In response to this challenge, a methodology has been proposed to capture the views of multiple stakeholders using fuzzy set theory and fuzzy logic. Three possible forms of individual stakeholders' input, scale (crisp), linguistic (fuzzy), and conditional (fuzzy), are analyzed to obtain the aggregated input by using Fuzzy Expected Value. The methodology is applied to flood management in the Red River Basin, Manitoba, Canada. The outputs derived from the three different input types show good correlation. Thus, the proposed methodology shows alternative ways of soliciting the opinion of a large number of stakeholders and aggregating those opinions for use in multi-objective decision making.