[01] Michael Gr. Voskoglou, Department of Applied Mathematics, Faculty of Technological Applications, Graduate Technological Educational Institute of Western Greece, Patras, Greece.

In this paper we develop a method for assessing the overall performance of groups of individuals participating in any kind of human activities. For this, we represent each of the groups under assessment as a fuzzy subset of a set U of linguistic labels characterizing its members’ performance and we use the centre of gravity defuzzification technique in converting the fuzzy data collected from the corresponding activity to a crisp number. According to the above method the higher is an individual’s performance the more its “contribution” to the corresponding group’s overall performance (weighted performance). Two real life applications are also presented, related to the bridge players’ performance and the students’ assessment respectively, illustrating our assessment method in practice.

Fuzzy Sets, Centre of Gravity (COG) Defuzzification Technique, Contract Bridge

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