Group Polarization - History and Origins

History and Origins

The study of group polarization can be traced back to an unpublished 1961 Master’s thesis by MIT student James Stoner, who observed the so-called "risky shift". The concept of risky shift maintains that a group’s decisions are riskier than the average of the individual decisions of members before the group met. The discovery of the risky shift was considered surprising and counter-intuitive, especially since earlier work in the 1920s and 1930s by Allport and other researchers suggested that individuals made more extreme decisions than did groups, leading to the expectation that groups would make decisions that would conform to the average risk level of its members. The seemingly counter-intuitive findings of Stoner led to a spurt of research around the risky shift, which was originally thought to be a special case exception to the standard decision-making practice. Many people had concluded that people in a group setting would make decisions based on what they assumed to be the overall risk level of a group; because Stoner’s work did not necessarily address this specific theme, and because it does seem to contrast Stoner’s initial definition of risky shift, additional controversy arose leading researchers to further examine the topic. By the late 1960s, however, it had become clear that the risky shift was just one type of many attitudes that became more extreme in groups, leading Moscovici and Zavalloni to term the overall phenomenon "group polarization".

Subsequently, a decade-long period of examination of the applicability of group polarization to a number of fields in both lab and field settings began. There is a substantial amount of empirical evidence demonstrating the phenomenon of group polarization. Group polarization has been widely considered as a fundamental group decision-making process and was well established, but remained non-obvious and puzzling because its mechanisms were not fully understood.