Reference-based ranking procedure for environmental decision making: insights from an ex-post analysis

Preference elicitation is a challenging activity in any decision-making process, yet preferences are fundamental since the recommendations are meaningful and acceptable only if the Decision Maker's values are taken into account. This study proposes an ex-post application of a recent ranking method named Simple Ranking with Multiple Points (S-RMP) to support a participatory decision making process. The method has been tested on a real-world case study simulating the selection of the most suitable site for locating a new landfill. The purpose of the research is twofold: (i) to explore the applicability and relevance of the S-RMP method to support environmental decisionmaking processes and (ii) to provide guidelines for the elicitation of preference parameters of the S-RMP ranking method. The results highlight that the proposed method opens a promising line of research in the environmental decision-making domain, thanks to its ability to use heterogeneous information consistently with the increasing amount of qualitative data embedded in real decisionmaking processes.