THEORY OF COLLECTIVE DECISION-MAKING IN HIERARCHICAL AND NON-HIERARCHICAL GROUPS

Using elements from the study of collective phenomena in physics, we build a simple model to describe processes of group decision-making. The theory is articulated around the concept of spontaneous symmetry breaking. It is found in particular that group polarization results from a whole class of phenomena and, not from a single phenomenon, as was believed up to now. Moreover, polarization is a direct function of interactions in the group. Competing effects such as ethical and cultural individual bias as well as external social pressures are also considered. Size effects are studied. Non-hierarchical as well as hierarchical systems are discussed. Perspectives are outlined.