MCDA

Any complex decisional problem requires to explicitly consider several points of view. The classical approaches (utility theory, game theory, benefit-cost analysis, mathematical programming, etc.) consider only one objective function to be maximised or minimised, hence they do not ensure a faithful modelisation of real world decision problems.

Many multidimensional approaches have been proposed as extensions of the classical ones. The first was the so called Multicriteria Decision Making (MCDM), developed by the American School.

More recently, the European School has created a new type of approach to these problems, called Multicriteria Decision Aid (MCDA). The MCDA, even if not perfectly axiomatised yet, tries to cope with the complexity of decision problems by relaxing the mathematical axiomatisation and by offering a more flexing way of modeling real world cases. Furthermore, several real life applications have successfully validated the feasibility of this approach.

For these reasons, MCDA is today one of the most important research fields in Operation Research.

Technically, MCDA deals with different classes of decisional problems (choice, classification, sorting, ranking), taking explicitly into consideration several points of view (multiple attributes or criteria, i.e. attributes with ordered domain), in order to support Decision Makers (DMs) (or stakeholders) to find a consistent solution of the problem at hand. Moreover, modern tools in preference modeling (such as fuzzy sets and rough sets) have been successfully applied in the framework of MCDA.

The scientific aspects and the practical applications have attracted a lot of researchers and practitioners towards MCDA world, stimulating both theoretical and methodological developments, as well as real life applications and specific software implementation.