This study aims to investigate the influence of construction schemes for non-compensatory composite indicators by multiplicative utility functions on the flood vulnerability assessment. The flood vulnerability outcomes are evaluated and compared for the 231 administrative districts in the Republic of Korea, based on the two composite indicators by different aggregation schemes from the three assessment components such as exposure, sensitivity, and coping, presented in The IPCC Third Assessment Report. The one scheme uses the coping component having a negative functional relationship with vulnerability as a divisor, and the other scheme employs the lack of coping component in the opposite concept to coping as a multiplier. As a result of comparison analysis, some districts show markedly large differences in the flood vulnerability ranking orders by the two different aggregation schemes using the same proxy variables. For robustness of flood vulnerability assessment outcomes, it is necessary to compile a non-compensatory composite indicator under the condition that all constituent assessment components have the same directional elasticity to vulnerability. This study can help to select a proper aggregation framework in constructing flood vulnerability indicators to provide useful information for supporting policy and decision-making on complex issues.
