RATIONAL GROUP DECISION-MAKING - A RANDOM-FIELD ISING-MODEL AT T=O

A modified version of a finite random field Ising ferromagnetic model in an external magnetic field at zero temperature is presented to desc ribe group decision making. Fields may have a non-zero average. A post ulate of minimum inter-individual conflicts is assumed. Interactions t hen produce a group polarization along one very choice which is howeve r randomly selected. A small external social pressure is shown to have a drastic effect on the polarization. Individual bias related to pers onal backgrounds, cultural values and past experiences are introduced via quenched local competing fields. They are shown to be instrumental in generating a larger spectrum of collective new choices beyond init ial ones. In particular, compromise is found to result from the existe nce of individual competing bias. Conflict is shown to weaken group po larization. The model yields new psychosociological insights about con sensus and compromise in groups.