A Combined Multi-criteria Risk Decision and Rank Aggregation Approach with Multiple Risk Factors with an Application to Greenhouse Gas Emission Risk Assessment of Sectors

Abstract In this work, a combined multi-criteria risk decision-making and rank aggregation method, WASPAS-WBR, is proposed for the risk assessment of alternatives according to different risk factors. The method consists first in applying the weighted aggregated sum product assessment (WASPAS) method, with criteria defined by risk measures, in order to obtain a ranking of the alternatives for a given risk factor. After obtaining the rankings for the different risk factors, the rank aggregation method weighted Borda ranking (WBR) is applied to establish a final ranking of the alternatives. The WASPAS-WBR method is illustrated with an application to the risk analysis of greenhouse gas emission by sectors, considering the risk factors carbon dioxide (CO $$_2$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mmultiscripts> <mml:mrow/> <mml:mn>2</mml:mn> <mml:mrow/> </mml:mmultiscripts> </mml:math> ), methane (CH $$_4$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mmultiscripts> <mml:mrow/> <mml:mn>4</mml:mn> <mml:mrow/> </mml:mmultiscripts> </mml:math> ), and nitrous oxide (N $$_2$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mmultiscripts> <mml:mrow/> <mml:mn>2</mml:mn> <mml:mrow/> </mml:mmultiscripts> </mml:math> O). The aim is to classify the sectors in terms of risk for greenhouse gas emission, first by evaluating the sectors according to each individual air pollutant using the WASPAS method with risk criteria mean, value at risk and tail value at risk, and then by assessing the combined risk with the WASPAS-WBR method. Data corresponding to annual greenhouse gas concentrations measured in Portugal in the time horizon from 1990 to 2022 are analyzed.