Modal split modelling using multicriteria analysis and discrete fuzzy sets

As users make transport mode choice decisions by taking several factors (criteria) into account, modal split may be regarded as a multicriteria problem and, therefore, solved using well-known multicriteria analysis methods. Many of the possible factors of relevance for modal split are hard to quantify precisely and reliably the way users do. Decisions are made by users who evaluate these factors as they see, feel or estimate them. The incorporation of fuzzy sets theory into the modal split modelling procedure is primarily intended to allow users to give ‘less precise’ answers to questions (in questionnaires) about relevant parameters (e.g. work trip duration: ‘short’, ‘long’, ‘around 5 minutes’, etc.) as well as to permit transportation planners to process these data and use them later. This is why the TOPSIS method, as a multicriteria method adapted to handling imprecise discrete quantities, can be employed for modal split modelling. This paper presents an attempt at modal split modelling using multicriteria analysis and discrete fuzzy sets.