A group is a collection of people who interact, share common goals, and influence how members think and act. Chapter 19 examines the kinds of groups people form and the effects of groups on their members and society.
Section 1 identifies group behavior and lists the factors that distinguish groups from aggregates. Group members are interdependent and share goals. Groups can be differentiated by in-groups and out-groups, primary groups and secondary groups, and as serving social functions and task functions. Shared norms and ideology strengthen the cohesiveness of groups. The study of group structure analyzes the roles of various group members and how these roles are interrelated. Group polarization and groupthink are two methods of group decision making. This section also discusses communication patterns and the nature of leadership within groups.
Section 2 is about how group behavior can influence people's conformity and obedience. Psychologists believe people conform to gain approval. Compliance occurs when we given in to social pressure in our public behavior, but do not actually change our private beliefs. This section lists the factors that increase conforming behavior in people. Researchers believe we obey authority because of social conditioning.
Section 3 details conflict and cooperation among groups. Aggression is a combination of biological, cognitive, personality, and environmental factors and contributes to conflict. Research shows that cooperation can be a factor in eliminating group hostility. Psychologists have found that the larger the crowd or group, the more likely that any given individual is to feel that he or she is not responsible for an action or behavior. Terms associated with this research are diffusion of responsibility, bystander effect, and social loafing. The section concludes with a discussion of deindividualization.