Group Decision Making in Linguistic Contexts: An Information Granulation Approach

Group decision making situations are part of today's organizations. It is a type of decision making involving many decision makers which act collectively to choose the best alternative (or alternatives) from a set of feasible alternatives. Usually, numerical values have been used by the decision makers to express their opinions on the possible alternatives. However, as the standard representation of the concepts that humans use for communication is the natural language, words or linguistic terms instead of numerical values should be used by the decision makers to provide their preferences. In such a situation, the linguistic information has to be made operational in order to be fully utilized. In this contribution, assuming that decision makers express their opinions by using linguistic terms, we present an information granulation of such a type of information, which is formulated as an optimization problem in which consistency is maximized by a suitable mapping of the linguistic terms on information granules.