Scaling Transformation in the Rembrandt Technique: Examination of the Progression Factors

This paper examines a decision support system (DSS) for the appraisal of complex decision problems using multi-criteria decision analysis (MCDA). The DSS makes use of a structured hierarchical approach featuring the multiplicative AHP also known as the REMBRANDT technique. The paper addresses the influence of the progression factor used when transforming the decision makers' verbal responses from a semantic to a geometric scale in REMBRANDT. Conventionally, the progression factor 2 is used for calculating scores of alternatives and √2 for calculation of criteria weights. Tests are conducted on the magnitude of these progression factors in order to examine the sensitivity towards the final outcome of an analysis. For illustration a case study concerning the appraisal of a large infrastructure project is presented. The results of the sensitivity calculations are compared with the results of a conventional AHP calculation in order to examine what impact the choice of progression factors as well as the choice of technique have on the decision making. Based on this a modified progression factor for the calculation of scores for the alternatives in REMBRANDT is suggested while the progression factor for the criteria weights is suggested to be kept unchanged. Finally, conclusions and perspectives are set out.