Group Decision-Making Quality

The need for broad representation and a wide range of expertise often necessitates the use of groups to make important decisions. Indeed, group decision making is evident in product development teams, corporate boards, juries, and emergency medical teams. Group decision making involves the process of reaching agreement on a given set of alternatives among multiple individuals. Through interaction and discussion, individual positions or preferences are transformed into a consensus choice. Research in this literature has mostly focused on small groups, typically with a size of 4 to 7 members but reaching up to 12 members in jury decision research. What distinguishes group from individual decision making is the need to reconcile various positions and preferences into a collective decision. A common assumption is that groups can make higher-quality decisions and better detect errors than individuals acting alone. However, research has shown that group outcomes are not always superior to those of individuals. Instead, the factors contributing to group decision-making success or failure are numerous, complex, and situationally contingent.

Advantages and Disadvantages of Group Decision Making

The belief that several heads are better than one underlies the reliance on groups to make important decisions in business, military, medical, and governmental contexts. Groups, as opposed to individuals, represent a diversity of perspectives, areas of expertise, and values. In addition, groups can distribute the responsibility for consequential decisions across many members. Furthermore, people may reject decisions made by a single authority, whereas collective decision making may increase the acceptability and ease of implementation of decisions.

Despite these advantages, however, group decision making also suffers from significant limitations. For example, groups often take longer to arrive at a choice than individuals. In addition, although group decision making is expected to lead to superior performance when no single member has all the necessary information to identify a correct solution, extensive laboratory research has revealed that groups tend to discuss information that is shared by all members as opposed to pooling the unique information held by individual members. Therefore, the potential for different individuals to bring independent, unshared, and valid information to the group is never realized, which contributes to incorrect group solutions. Nevertheless, information sharing has been found to improve over time, and leadership as well as training can improve the dissemination of knowledge in teams.

Although groups are often expected to neutralize individual biases in decision making, they have been found to fall prey to some of the same errors as individuals. The question of whether groups are any less subject to judgmental biases than individuals depends on a variety of factors, including group size and the type and magnitude of bias, as well as group processes.

Some research has found that groups exaggerate the biases of individual group members. Specifically, group polarization refers to the finding that groups are more extreme than the mean of individuals. For example, if members adopt a cautious or risky viewpoint prior to group discussion, they tend to have an even more cautious or risky viewpoint after deciding together as a group.

Another disadvantage to group decision making is the potential for groupthink, which has received much emphasis in the literature. Groupthink occurs when the premature striving for agreement among members produces faulty decisions. To combat these limitations and improve group decision making, many techniques have been proposed to establish new patterns of social interaction, change the sequence of steps in information processing, or develop specific procedures for task accomplishment.

Types and Stages of Group Decision Making

There are two major categories of group decision making. One type involves members discussing decision alternatives and combining their preferences to arrive at a collective solution. A second type is called hierarchical decision making because a team leader asks for input from group members, but that team leader makes the final decision. For example, a department chair may be advised and informed by various faculty committees but determines the final choice alone.

Similar stages have been proposed for both individual- and group-level decision making, namely issue identification, alternative generation, evaluation, and choice. During issue identification, relevant information is acquired and issues are defined and interpreted. In the alternative generation stage, decision criteria are chosen and alternatives are proposed. Finally, alternatives are evaluated and a decision is selected. Some models of group decision making also include an implementation phase in which actions are coordinated and monitored.

Group Decision-Making Effectiveness

Two broad categories that can be used to assess group decision-making effectiveness are decision outcomes and affective outcomes. Decision outcomes include acceptance of the decision by those affected by it, whether the decision stands or is subsequently overturned, and how successfully it is implemented. In addition, decision accuracy or quality has been researched extensively. Affective outcomes include satisfaction with the final decision, fairness of the processes used to arrive at consensus, and whether members would like to continue working together. Both short- and long-term outcomes should be considered in the assessment of decision-making effectiveness.

Factors Contributing To Group Decision-Making Effectiveness

Existing models recognize that effective and ineffective group decision making is determined by a wide range of factors. A sampling of the variables that have been investigated in this literature follows.

Decision Rule

Group members must implicitly or explicitly select and implement decision rules to determine how individual preferences will be combined to produce a collective decision. Majority rule and unanimity are the most common methods of social choice. In a simple majority, 51% or more of group members must agree, whereas unanimity requires that all members agree. Group decisions often are more difficult to reach and require more discussion under unanimity rule than under majority rule. In contrast, majority rule is more efficient and less time-consuming, and it prevents impasses more than does unanimity. However, majority rule may not be the preferred decision rule in groups with conflicting viewpoints, because it cannot always resolve diverse preferences in a way that contributes to effective group functioning. Unanimity drives groups toward more systematic processing of information because attention must be paid to all members’ perspectives.

Social Decision-Making Schemes

Related to decision rules, prediscussion preferences of group members can be related to group decisions through simple functions or rules, termed social decision schemes. Examples include majority rule (group decision is favored by more than half of group members), truth wins (one correct member is necessary and sufficient for a correct group response), and truth supported (two correct members are necessary and sufficient for a correct group response).

Social decision schemes are probabilistic models, and their fit can be assessed through statistical tests. A reoccurring finding in this research is that groups tend to decide for an alternative that is supported by the majority of members, despite the fact that it may not be the correct solution. However, a major value of this research has been to trace the ways in which the best fitting or most predictive social decision scheme varies with the decision environment and type of task. For example, truth wins tends to be the best fitting social decision scheme for intellective tasks where a demonstrably correct solution exists. In contrast, truth supported tends to be the best fitting combination process for general world knowledge and vocabulary. Furthermore, the best fitting social decision scheme for juries is a two-thirds majority.

Minority Influence

In the absence of dissenters, convergent thinking strategies are used, which involve a narrow focus with little cognitive effort. However, the presence of dissenting minorities causes group members to think more divergently; that is, their thoughts cover a wider range of perspectives. Majority members seek understanding of the minority position to better reject it, and the tension produced by conflicting perspectives produces divergent thinking. As a result, groups with dissenting minorities have been found to produce more innovative ideas than groups without dissenting minorities.


In the past 15 years, it has been recognized that conflict can be a functional and stimulating mechanism in groups as opposed to a stressful and disruptive event. As a result, some decision-making interventions such as devil’s advocacy encourage group members to challenge each other’s ideas to foster debate and critical analysis. Some research suggests that these techniques do yield better group decisions. However, not all conflict is beneficial. Although task-related conflict fosters a deeper discussion of the issues by fostering disagreement about ideas, relationship conflict results in animosity, anger, and tension between group members.

Group Decision Making In Organizations

The majority of research in group decision making has been conducted by social psychologists who mostly use laboratory experiments and ad hoc groups. Therefore, it is not clear if all results can be generalized to groups in organizations, in which members have a history and stay together for extended periods of time. However, over the past decade, organizational psychologists have gotten more involved in group decision-making research to overcome the artificiality of laboratory work. Recent group decision-making models include more real world variables such as political factors, stress from external threats, member history, and the likelihood of future group interactions. Therefore, it is expected that new insights will be gained concerning the effects of organizational factors on group decision making in the next few years.


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