Group Decision Making

History

The scholarly analysis of group decision making can be traced as far back as the philosophies of Socrates and Aristotle. The Socratic dialogue, for example, is predicated on the assumption that collective discourse can lead to greater truths than can solitary reflections. While there are some laudable exceptions, it was not until the emergence of social psychology in the 1930s that the study of group decision making took on its contemporary shape. This approach, initiated by such luminaries as Kurt Lewin, Muzafer Sherif, and Floyd Allport, emphasizes the collection of scientific evidence. Notably, while social psychology is the discipline most closely associated with the establishment and current study of group decisions, many important contributions have come from other fields, including sociology, business, education, and political science.

An early debate centered on the basic question of whether or not groups could be considered “real” in the sense of having scientifically measurable properties that transcend their individual members. Allport argued that they did not. He contended that groups could be wholly understood by studying their member individuals and that this was the only scientifically valid position. Others, including Lewin and Sherif, argued to the contrary. Through the collection of empirical data and persuasive theorizing, the debate was largely settled by the 1950s in favor of the groups approach, although vestiges of the rift remain to this day.

Some early studies on group decision making identified pseudo-group effects, outcomes that seem to emerge from groups but are attributable to statistical principles. For example, when several people combine their inputs to generate a single decision, they will reliably outperform individuals working alone. However, this effect can be attributed to the statistical principle of aggregation. Increasing the size of a group can also lead to a better outcome simply because it increases the probability that one of the individuals will have the requisite skills or knowledge. While such effects are real, they can be explained with statistical principles and are generally rejected as true group effects. However, this does not mean that such effects are unimportant or uninteresting. Indeed, mathematical models of group decision making that incorporate such considerations continue to be developed. Nonetheless, for most contemporary researchers, a true group effect necessarily involves individuals who are interdependent and engaged in social interaction.

Studying Group Decision Making

The methods used to study group decision making include experimental designs, which allow for the systematic manipulation and control of variables, and correlational designs, in which naturally occurring variables are carefully measured (but not manipulated) to see if they are reliably associated. Field studies of actual groups (e.g., committees, juries, clubs, fraternities, teams) typically employ correlational designs but may include experimental variables as well. A case study is an in-depth descriptive analysis of a single group, often one that has made a notorious decision. Each of these basic research designs offers unique advantages and disadvantages. For example, experimental designs allow for superior confidence in determining causality (e.g., Does time pressure cause group tension?); correlational designs allow researchers to study variables of interest that cannot be manipulated (e.g., gender, personality); and case studies, while not suitable as scientific evidence, can provide fascinating [Page 389]illustrations of established principles or may serve to stimulate scientific investigations.

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