Note on the integration of prototype theory and fuzzy-set theory

Many criticisms of prototype theory and/or fuzzy-set theory are based on the assumption that category representativeness (or typicality) is identical with fuzzy membership. These criticisms also assume that conceptual combination and logical rules (all in the Aristotelian sense) are the appropriate criteria for the adequacy of the above “fuzzy typicality”. The present paper discusses these assumptions following the line of their most explicit and most influential expression by Osheron and Smith (1981). Several arguments are made against the above identification, the most important being that representativeness in prototype theory is exclusively based on element-to-element similarity while fuzzy membership is inherently an element-to-category relationship. Also the above criteria for adequacy are criticized from the viewpoint of both prototype theory and fuzzy-set theory as well as from that of both conceptual and logical combination, and also from that of integration.     

Effects of a Psychologically Based Management System on Work Motivation and Productivity

Introducing group work as a principle of work organisation to increase productivity in organisations operating in a globalising economy requires new methods of measuring performance in groups. This study describes the introduction of a measurement instrument as part of a participative productivity management (PPM) system in a medium sized factory producing rubber compounds. Using a simple quasi-experimental design, the PPM intervention was found to produce an increase in productivity and was also related to goal clarity, but not to higher group cohesion. It is concluded that PPM helps to increase productivity mainly by increasing task and goal clarity, and that increases in productivity can only be reached reliably when no competing system of performance appraisal exists besides PPM.