We started out this chapter by looking at how groups are defined and perceived. One determinant of the perception of a group is a cognitive one—the perception of similarity. A group can only be a group to the extent that its members have something in common. A group also has more entitativity when the group members have frequent interaction and communication with each other. Interaction is particularly important when it is accompanied by interdependence—the extent to which the group members are mutually dependent upon each other to reach a goal. A group that develops group structure is also more likely to be seen as a group. The affect that we have toward the group we belong to—social identity—also helps to create an experience of a group. Most groups pass through a series of stages—forming, storming, norming and performing, and adjourning—during their time together.

Because groups consist of many members, group performance is often better, and group decisions generally more accurate, than that of any individual acting alone. On the other hand, there are also costs to working in groups—we call them process losses.

A variety of research has found that the presence of others can create social facilitation—an increase in task performance—on many types of tasks. However, the presence of others sometimes creates poorer individual performance—social inhibition. According to Robert Zajonc’s explanation for the difference, when we are with others, we experience more arousal than we do when we are alone, and this arousal increases the likelihood that we will perform the dominant response—the action that we are most likely to emit in any given situation. Although the arousal model proposed by Zajonc is perhaps the most elegant, other explanations have also been proposed to account for social facilitation and social inhibition.

We can compare the potential productivity of the group—that is, what the group should be able to do, given its membership—with the actual productivity of the group by use of the following formula:

actual productivity = potential productivity − process loss + process gain.

The actual productivity of a group is based in part on the member characteristics of the group—the relevant traits, skills, or abilities of the individual group members. But group performance is also influenced by situational variables, such as the type of task needed to be performed. Tasks vary in terms of whether they can be divided into smaller subtasks or not, whether the group performance on the task is dependent on the abilities of the best or the worst member of the group, what specific product the group is creating, and whether there is an objectively correct decision for the task.

Process losses are caused by events that occur within the group that make it difficult for the group to live up to its full potential. They occur in part as a result of coordination losses that occur when people work together and in part because people do not work as hard in a group as they do when they are alone—social loafing.

In terms of decision making, we reviewed many reasons why groups can and often do make better choices than individuals, for example, due to their wider knowledge base, their superior collective and transactive memories, and their greater ability to spot and correct mistakes. However, we also saw a number of phenomena illustrating when and how groups can make poorer decisions than individuals.

One such group process that can lead to very poor group decisions is groupthink. Groupthink occurs when a group, which is made up of members who may actually be very competent and thus quite capable of making excellent decisions, nevertheless ends up making a poor decision as a result of a flawed group process and strong conformity pressures. And process losses also occur because group members tend to the shared information bias, which is a tendency to discuss information that they all have access to while ignoring equally important information that is available to only a few of the members.

One technique that is frequently used to produce creative decisions in working groups is brainstorming. However, as a result of social loafing, evaluation apprehension, and production blocking, brainstorming also often creates a process loss in groups. Approaches to brainstorming that reduce production blocking, such as group support systems, can be successful.

Group polarization occurs when the attitudes held by the individual group members become more extreme than they were before the group began discussing the topic. Group polarization is the result of both cognitive and affective factors.

Group members frequently overvalue the productivity of their group—the illusion of group effectivity. This occurs because the productivity of the group as a whole is highly accessible and because the group experiences high social identity. Thus groups must be motivated to work harder and to realize that their positive feelings may lead them to overestimate their worth.

Perhaps the most straightforward approach to getting people to work harder in groups is to provide rewards for performance. This approach is frequently, but not always, successful. People also work harder in groups when they feel that they are contributing to the group and that their work is visible to and valued by the other group members.

Groups are also more effective when they develop appropriate social norms—for instance, norms about sharing information. Information is more likely to be shared when the group has plenty of time to make its decision. The group leader is extremely important in fostering norms of open discussion.

One aspect of planning that has been found to be strongly related to positive group performance is the setting of goals that the group uses to guide its work. Groups that set specific, difficult, and yet attainable goals perform better. In terms of group diversity, there are both pluses and minuses. Although diverse groups may have some advantages, the groups—and particularly the group leaders—must work to create a positive experience for the group members.

Your new knowledge about working groups can help you in your everyday life. When you find yourself in a working group, be sure to use this information to become a more effective group member and to make the groups you work in more productive.