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date: 18 July 2024

Group Processesfree

Group Processesfree

  • Charles StangorCharles StangorDepartment of Psychology, University of Maryland at College Park


Group process refers to the behaviors of the members of small working groups (usually between three and twelve members) as they engage in decision-making and task performance. Group process includes the study of how group members’ characteristics interact with the behavior of group members to create effective or ineffective group performance. Relevant topics include the influences of group norms, group roles, group status, group identity, and group social interaction as they influence group task performance and decision-making, the development and change of groups over time, group task typologies, and decision-making schemes. Relevant group outcomes include group cohesion, process losses and process gains in performance, free riding, ineffective information sharing, difficulties in brainstorming, groupthink, and group polarization. Other variables that influence effective group process include group member diversity, task attractiveness, and task significance. A variety of techniques are used to improve group process.


  • Organizational and Institutional Psychology
  • Social Psychology


Humans are social animals who cooperate with each other to survive and flourish. Human–human interactions occur at many levels, including friendships, romantic relationships, neighborhoods, communities, and organizational structures. Group process refers to one aspect of human cooperation—the behavior of human beings as they work together to make decisions, solve problems, and perform tasks in working groups of between three and twelve members (Brown, 2000; Castellan, 2013; Hackman & Katz, 2010; Homans, 1950; Stangor, 2016; Turner, 2014). The applications of group process are broad, ranging from student study groups to juries (Bornstein & Greene, 2011; Kaplan & Martín, 2013; Vidmar & Hans, 2007) and work teams (Lipnack & Stamps, 2008; Rousseau, Aubé, & Savoie, 2006).

This article relates specifically to the processes that occur in working groups. Other topics related to social groups but not covered in this article include close relationships, leadership, and intergroup relations.

Groups can be studied from group-level approaches (in which the focus is upon the groups themselves rather than on the individuals who make up the groups) or from the individual level, in which the focus is upon the individuals who make up the groups. Bridging these two approaches, the study of group process is based on the principle of group dynamics (Cartwright & Zander, 1968), the idea that group behavior is a system of reciprocal interactions between groups and individuals. Group dynamics was developed in large part by the social psychologist Kurt Lewin, who summarized his belief that both individuals and groups were important in what has now become a well-known equation in the social sciences:


This equation indicates that the behavior of an individual is a function of both the individual (person) characteristics as well as the influence of the other people in their social environment. The relationship is dynamic because changes in the group affect the individual, and changes in the individual affect the group.

Characteristics of Working Groups

The focus of group process is on working groups as they perform their assigned functions and attempt to meet their goals. Basic principles underlie group process and these dimensions can be measured to characterize the current status of the group. Characteristics of working groups include similarity among the group members, interaction (communication) among the members, interdependence of the members in meeting goals, and a group structure that defines group function and performance.

Group structure includes norms about the appropriate relationships and behaviors among the group members. Group roles are norms that specify the behaviors expected to be performed by individual group members. The task-oriented role refers to a set of behavior patterns that involve working toward production and goal achievement. Individuals who assume task-oriented roles assign tasks, coordinate activities, and monitor and criticize the performance of others. The socioemotional role, on the other hand, involves behaviors that provide support to group members and attempts to keep group interactions harmonious. Those who assume the socioemotional role consider the feelings of the other group members, which is accomplished through open, friendly communications. The task role and the socioemotional role together account for the behavior patterns of many group members.

The need to fulfill roles may in some cases cause problems for the group and its members. One potential difficulty—role ambiguityoccurs when the group expects the individual to perform a role but at the same time does not provide sufficient information about how to do it. Role ambiguity may be a particular problem for new group members or for those who have been given new positions until the roles become clear for them.

Role conflict occurs when the individual is expected to fulfill more than one role or when the demands from one set of people compete with those of another set of people. Role conflict can occur when the individual is expected to play two separate and yet competing roles (trying to be both a manager and a friend to subordinates) or when playing the same role produces conflicting demands (an employee balancing parental duties with work-related travel requirements). Because role ambiguity and role conflict create sources of stress for the individual, they will eventually harm the group’s productivity unless group leaders provide explicit information about roles and role priorities.

Figure 1.

Group structure also includes communication patterns among group members. In some working groups the communication patterns are relatively limited, and information is sent primarily to and from one or a few individuals—for instance, in a hierarchical structure, as demonstrated in Figure 1.

Figure 2.

In other cases, however, the flow of communication in the group may be more open, decentralized, and lateral—for instance, if the workers are encouraged to share information directly with each other, as demonstrated in Figure 2.

Group Status

Group status is the amount of authority, prestige, or reputation that a group member has in the group. Status is assessed by measuring the ability of the individual to influence the opinions of the other members of the group, by the extent to which the individual is perceived as helping the group meet its goals, or by evaluating the patterns of communications among the group members. Individuals with high status in a group tend to speak more frequently, are more likely to be allowed to interrupt the conversation of others, and have more influence over group decisions.

Especially when a group is first forming, individuals’ social category memberships play a large role in determining their status. The status that one accrues as a result of one’s social category memberships is called diffuse status (Correll & Ridgeway, 2006). In most cases, men have more diffuse status than women, older people have more diffuse status than younger people, those with high-paying occupations have more diffuse status than those with low-paying occupations, and (at least in the United States) whites have more diffuse status than blacks.

The effects of diffuse status are problematic for working groups when group members make inferences about the likely performance of an individual on the basis of his or her status characteristics. Individuals with low diffuse status are perceived as less effective group members even though they may well be effective contributors.

Over the long run, status will be determined in large part by the individual’s perceived ability to lead the group toward its goals. Status that is gained through effective and competent performance on the group tasks is called specific status. Those who have particular knowledge or skills that are needed for effective group functioning, or who create useful ideas or plans, will be accorded specific status within the group.

People gain status in groups in part by expressing and earning their dominance over others in social interaction. People who talk more and louder, and who initiate more social interactions, are afforded higher status, even when their contribution to meeting the group goals is not actually greater than that of others (Hall, Coats, & LeBeau, 2005). Group status may also be earned by engaging in behaviors that are approved of by the group—for instance, by conforming to group norms or publicly expressing positive feelings about the group and its opinions (Hollander, 1958).

Group Outcomes

Group structure, status, roles, and physical space influence group outcomes, including cohesion, identity, and performance.

One approach to assessing the meaning of groups for individuals is to assess the cohesion of the group. Group cohesion is the positive emotional attachment that group members have with the other members of the group. A group is said to be cohesive to the extent that the group members are attracted to the other group members, feel that they are part of the group, want to stay in the group, and find the group important to them (Evans & Dion, 2012).

Cohesion in social groups is associated with greater group satisfaction, morale, and trust, along with less anxiety, more positive group communication, and fewer absences from meetings (Gal, 1986; Seashore, 1954). Although very high group cohesion can be problematic, in general, higher levels of cohesion are related to better group performance (Evans & Dion, 2012).

Groups members also develop a group social identity—the part of our self-concept that results from our membership in social groups (Ellemers & Haslam, 2012; Tajfel & Turner, 1979). Generally, because we prefer to remain in groups that we feel good about, the outcome of group membership is a positive social identity—our group memberships make us feel good.

Another important outcome of group interaction is the satisfaction of the group members with their experiences in the group, group member satisfaction. Positive social interactions and relationships among the group members are important for effective group functioning.

Group Development and Change

A variety of theories about how working groups develop and change over time have been proposed (Bonebright, 2010; Cassidy, 2007; Tuckman, 1965). Although all of the theories share the common assumption that groups are dynamic rather than static, they differ in the level of analysis they have used to understand the problem.

Some models of group development have been framed at the level of the group, proposing that groups pass through a series of states or stages over time. Some of these models assume that the stages of group development are sequential, but the patterns of changes in groups may not always be that well organized, and acknowledging this, other models suggest that different groups reach different stages in different orders, that some stages may be skipped, and that groups may also return to earlier stages over time.

Some researchers who favor sequential models of group development have compared the stages of group functioning to stages in the development of human beings. Just as a human being progresses from birth, through childhood, adolescence, adulthood, old age, and eventual death, so a social group, such as a musical group, a club, or a business, may also pass through a series of sequential stages. A description of these stages is found in Table 1.

Table 1. Stages of Group Development

Stage of Group Development



The group members come together and share information.


The group norms are solidified.


Group members challenge existing norms leading to conflict within the group.


The group completes its assigned tasks and disbands.

Some researchers have been critical of the group-level approach to understanding changes in groups over time, arguing that it is necessary to take into consideration not only the changes in the group, but also changes in relationships between the individual and the group (Levine & Moreland, 1994). These authors suggest that a full understanding of group growth must take into consideration that groups and individuals are sometimes in harmonious relationships, but that at other times their relationships are more strained. Thus, group development involves not just changes in the group as a group, but rather the evolution and change of the relationships between the group and its individual members.

Group Task Performance

The group dynamics approach can be used to predict the likely performance of a working group. Group performance depends on both on the skills of the group members (member characteristics) and on the way these resources are combined in the group itself (group process). Member characteristics include the traits, skills, or abilities of the individual group members. It is assumed that the performance of the group as a whole—known as the potential group productivity—is related to the member characteristics. On a task such as rope pulling, the potential group productivity (the strength with which the group should pull when working together) would be calculated as the sum of all of the individual inputs, whereas on a decision-making task, the potential group productivity (the ability of the group to solve the problem) might be calculated as the ability of the best group member to solve the problem.

Although the member characteristics define the expected productivity of the group, the actual productivity of the group (the amount that the group is actually able to pull, or whether the group actually solves the problem) will generally be different from the potential productivity. The difference between the expected productivity of the group and the actual productivity of the group is determined by the group process itself. When the outcome of the group performance is more or better than would be expected on the basis of the member characteristics, it is called a process gain, whereas when the outcome of the group performance is less or worse than would be expected on the basis of the member characteristics, it is called a process loss. The following equation expresses this relationship:

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

Task Classifications

Steiner (1972) developed a system for classifying group tasks. The idea that we can better understand group performance by classifying tasks has guided subsequent research, and the classifications are summarized in Table 2.

Table 2. Classifying Group Tasks

Task division

Divisible: A task in which the work can be divided up among individuals

Unitary: A task in which the work cannot be divided up among individuals

Task combination

Additive: A task in which the inputs of each group member are added together to create group performance

Compensatory: A task in which group input is combined so that individual performance is averaged

Group member performance

Disjunctive: A task in which group performance is determined by its best member

Conjunctive: A task in which group performance is determined by its worst member

Task assessment

Maximizing: A task that involves performance that is measured by how rapidly group members work, or how much of a product they are able to make

Intellective: Tasks that involve the ability of the group to make a decision or judgment

Task clarity

Criterion: Tasks in which there is a clearly correct answer to the problem that is being posed

Judgmental: Tasks in which there is no clearly correct answer to the problem that is being posed

Process Gains and Process Losses in Group Performance

In some early experiments studying group performance conducted by Triplett (1898), racers who were competing with other cyclers rode significantly faster than cyclers who were racing alone, against the clock. Supporting the idea that the presence of competition, or even just a passive audience, can increase performance, subsequent studies have shown that the presence of others can increase performance on maximizing tasks, including jogging, shooting pool, lifting weights, and working on math and computer problems.

Despite the potential for some process gains in the presence of others, process losses are more common. Process losses occur regularly on maximizing tasks, and are caused by both the difficulty of coordinating the performance of the individuals and by the tendency of individuals to reduce their effort when they are in groups.

In an important set of studies demonstrating process losses, Ringelmann (1913; reported in Kravitz & Martin, 1986) investigated the ability of individuals to reach their full potential when working together on tasks. In his best-known study, Ringelmann had men, individually and in groups of various sizes, pull as hard as they could on ropes while he measured the maximum amount that they were able to pull. Ringelmann assumed that rope pulling was an additive task, and thus that the total amount that could be pulled by the group should have been the sum of the contributions of the individuals. However, although he did find that adding individuals to the group increased the overall amount of pulling on the rope, he also found a substantial process loss. The loss was so large that groups of three men pulled at only 85% of their expected capability, whereas groups of eight pulled at only 37% of their expected capability.

This phenomenon, in which group productivity decreases as the size of the group increases, is known as the Ringelmann effect. The effect has been shown in many other experiments and on a wide variety of tasks, including pumping air, clapping and cheering, folding papers, swimming, and evaluating a poem. Furthermore, these process losses have been observed in different cultures, including India, Japan, and Taiwan.

One of the causes of process losses, such as those observed by Ringelmann, is that the maximum group performance can only occur if all of the participants put forth their greatest effort at exactly the same time. Thus, actual productivity in the group is reduced in part by coordination losses. Coordination losses become more problematic as the size of the group increases, because coordinating the group members becomes correspondingly more difficult.

In addition to being able to coordinate their activities, group members must also be motivated to put in individual effort on the task. Motivation losses are process losses that occur when the individuals do not work as hard in the group as they do when they are alone. The reduction in motivation and effort that occurs when individuals work together at a group task is known as social loafing, and it has been found in many experiments (a meta-analysis conducted by Karau & Williams, 1993, reported a moderate effect size of .44).

Free riding is to a type of social loafing that occurs when individuals rely on other group members to do the work for the group. Individuals free ride when it seems that their contribution doesn’t matter, even if their performance is being monitored (Kerr & Bruun, 1983). The sucker effect occurs when individuals perceive that they are contributing more to a task than others, which leads the individuals to withhold effort as a means of restoring equity and avoiding being taken advantage of (Kerr, 1983).

Many studies have now investigated the determinants of social loafing, and some of these factors are summarized in Table 3.

Table 3. Determinants of Social Loafing

Group size

As groups get bigger, people feel more dispensable─their contribution does not seem as important and they withhold effort.

Group norms

Norms for hard work may increase effort but norms for low performance may prevent people from contributing.

Task attractiveness and significance

Tasks that are seen as rewarding and in which people feel that they have autonomy produce less social loafing.


When team members are given specific, attainable goals, they are likely to work to meet them.

Identifiability and deindividuation

When the individual contribution of group members is not known, they are likely to disengage. Making the contribution of each group member known decreases social loafing.

Social identity

People who strongly identify with a group are less likely to engage in social loafing than those who weakly identify.

Social Facilitation and Social Inhibition

Perhaps the most complete and best-studied explanation of the influence of others on task performance was proposed in 1965 by Robert Zajonc. Zajonc made use of the concept of drive arousal, which refers to the excitement and energy that occurs when other individuals are nearby. According to Zajonc’s theory, the arousal that is produced by the presence of others, and the resulting effort put forward by the individual in these situations, increases the likelihood that the individual will perform the dominant response, where the dominant response is defined as the action that an individual is most likely to emit in a given situation.

The important aspect of Zajonc’s theory is that the experience of arousal and the resulting increase in the performance of the dominant response could be used to predict whether the presence of others would either increase or decrease performance. Zajonc argued that when the task to be performed is relatively easy, or when the individual has learned to perform the task very well, the dominant response is likely to be the correct response, and the increase in drive caused by the presence of others would thus increase performance. On the other hand, when the task is difficult or not well learned, the dominant response is likely to be the incorrect one, and thus because the increase in arousal increases the occurrence of the (incorrect) dominant response, performance is hindered.

Zajonc’s theory explained how the presence of others can both increase and decrease performance, depending on the nature of the task, and a great deal of experimental research has now confirmed his predictions. Indeed, one meta-analysis conducted to review the findings of over 200 studies using over 20,000 research participants found that the presence of others did significantly increase the rate of performance on simple tasks and decreased both the rate and the quality of performance on complex tasks (Bond & Titus, 1983).

Group Decision-Making

As is common in assessments of task performance, group decision-making is also likely to result in process losses—the outcomes of group decision-making are not as good as we might expect given the quantity and quality of group members.

Decision Schemes

When analyzing decision-making it is common to assess not the outcome of the decision but the group process itself. In this case, the question is not whether the group gets the right answer, but how it reaches whatever decision it makes. This approach is particularly useful with intellective, judgmental tasks—those in which a decision has to be made, but in which there is no way to know whether the final decision was the correct one (Swaab, Galinsky, Medvec, & Diermeier, 2012). As summarized in Table 4, there are many potential decision schemes that might serve as the basis of group decision-making, and which one is most predictive of the group decision depends on the specific task being performed.

Table 4. Decision Schemes

Decision scheme


Likely occurrences

Truth wins

Group solves the problem if any single member finds the correct answer

Criterion-based tasks in which the correct answer is clear (Eureka tasks)

Truth-supported wins

Group solves the problem if any two members agree on which answer is correct

Criterion-based tasks in which the correct answer is not obvious (non-Eureka tasks)

First shift

Accept a decision as soon as one group member changes his or her opinion to accept it

Criterion-based tasks in which the correct answer is not obvious (non-Eureka tasks)

Majority wins

The group votes, and chooses an option if it is agreed on by over 50% of the group members

Judgmental tasks, such as jury trials


All group members must agree on the decision, or no decision can be made

Some jury trials

Random selection among alternatives

Group members randomly select one out of the potential alternatives

Very difficult tasks where there are several proposed alternatives and no correct answer is apparent

Turn-taking among proposed alternatives

Group members choose a different one of the alternatives at different times

Very difficult tasks where there are several proposed alternatives and no correct answer is apparent


Groups will not make effective decisions unless they are able to make use of the advantages that come with group decision-making, such as the ability to pool information and to test out contradictory ideas through group discussion. However, these conditions are not always met in real groups. One example of a group process that can lead to poor decisions is groupthink. Groupthink occurs when a group that is made up of members who may actually be very competent and thus quite capable of making excellent decisions, nevertheless ends up, as a result of a flawed group process and strong conformity pressures, making poor decisions (Janis, 1982; Packer, 2009). Groupthink is more likely to occur in groups in which there is very high group cohesiveness, when there is a strong and directive leader, and in times of stress and crisis. Groups suffering from groupthink are unwilling to seek out or discuss discrepant or unsettling information about the topic at hand, and they do not express contradictory opinions. Because the group members are afraid to express opinions that contradict the prevailing group norms, the group is prevented from making a fully informed decision.

Thus, antecedent conditions of groupthink include time pressure and stress, high cohesiveness and social identity, isolation from other sources of information, and directive, authoritative leadership. Symptoms of groupthink include illusions of invulnerability, illusions of unanimity, in-group favoritism, little search for new information, incomplete sharing of information, belief in the morality of the group, and pressure on dissenters to conform to group norms.

Most research that has studied groupthink has been based on descriptive analyses of real groups that have made poor decisions, such as those concerning the Bay of Pigs or the disastrous launch of the space shuttle Challenger. The general finding is that the quality of important decisions is negatively related to the number of groupthink-related symptoms. However, although the existing research generally provides evidence of the occurrence of groupthink, and the negative outcomes that result from it, it should nevertheless be kept in mind that these studies have exclusively focused on situations in which groups have already made poor decisions. As a result, the reviews may selectively ignore situations in which highly cohesive groups made good decisions. More definitive conclusions about the effects of groupthink-related symptoms on decision-making come from experimental research, and at least some experimental findings have been interpreted as supporting the basic principles of groupthink.

One of the most important predictions regarding groupthink—that highly cohesive groups should be more subject to groupthink than are less cohesive groups—has not always been supported. Indeed, Leana (1985) found that highly cohesive groups shared more information than did noncohesive groups, and also did not make riskier decisions. High group cohesiveness does not always relate to poor group performance, but may in fact lead to good decisions if the group norms are to be creative and to spend time making the decision.

A recent analysis of groupthink by Baron (2005) has suggested that although Janis was right in many ways about the causes and outcomes, he also underestimated its prevalence. Groupthink may be more ubiquitous than even Janis expected—it occurs even when the supposed necessary conditions are not present.

The Problem of Unshared Information

Although group discussion generally improves the quality of a group’s decisions, this is true only if the group discusses the information that is most useful to the decision that needs to be made. One difficulty is that groups tend to pay attention to, and discuss, some types of information more than others (Halevy & Chou, 2014; Stasser & Vaughan, 2013).

In addition to motivational pressures to preferentially consider information that supports group norms and values, discussion is also influenced by the way the relevant information is originally shared among the group members. The problem is that group members tend to discuss information that they all have access to, while ignoring equally important information that is available to only a few of the members.

Not only is unshared information less likely to be discussed, it is also frequently forgotten and is not included in the group discussion because the group members return to discuss shared information more often than unshared information. Therefore, effective discussion requires not only being sure that the group members bring up the relevant information, but also being sure that they actively consider it and maintain focus on it.

Although the tendency to poorly share information seems to occur quite frequently, at least in experimentally created groups, it does not occur equally under all conditions. Groups have been found to better share information when the group members believe that there is a correct answer that can be found if there is sufficient discussion (Stasser & Stewart, 1992), and groups also are more likely to share information if they are forced to continue their discussion even after they believe that they have discussed all of the relevant information (Larson et al., 1994).

Brainstorming and Creativity in Groups

One technique that is frequently used in attempts to produce creative decisions in working groups is known as brainstorming. When brainstorming:

Each group member is to create as many ideas as possible, no matter how silly, unimportant, or unworkable they are thought to be.

As many ideas as possible are to be generated by the group.

No one is allowed to offer opinions about the quality of an idea (even one’s own).

Group members are encouraged and expected to modify and expand upon one another’s ideas.

Despite its potential, the effectiveness of brainstorming is limited (Nijstad & Stroebe, 2006). In fact, virtually all individual studies, as well as meta-analyses of those studies, find that, regardless of the exact instructions given to the group, brainstorming groups do not generate as many ideas as one would expect, and the ideas that they do generate are usually of lesser quality than those generated by nominal groups of equal size. Thus, brainstorming represents another example of a case in which, despite the expectation of a process gain by the group, a process loss is instead observed.

Perhaps the most obvious potential detriment to effective brainstorming is social loafing by group members. For instance, Paulus and Dzindolet (1993) found that social loafing in brainstorming groups occurred, in part, because individuals perceived that the other group members were not working very hard, and they matched their own behavior to this perceived norm.

Evaluation apprehension also reduces the effectiveness of brainstorming groups. When individuals are told that other group members are more expert than they are, they reduce their own contributions (Collaros & Anderson, 1969), and when they are convinced that they themselves are experts, their contributions increase (Diehl & Stroebe, 1987).

Although social loafing and evaluation apprehension seem to cause some of the problem, the most important difficulty that reduces the effectiveness of brainstorming in face-to-face groups is that the mere fact of being with others hinders opportunities for idea production and expression. In a group, only one person can speak at a time, and this can cause people to forget their ideas because they are listening to others or to miss what others are saying because they are thinking of their own ideas. This problem is known as production blocking (Diehl and Stroebe, 1987).

Although research has demonstrated that brainstorming is not always effective, people who participate in brainstorming groups nevertheless think that they will be more productive than if they were to work alone (Stroebe, Diehl, & Abakoumkin,1992). Furthermore, those who have already participated in task-performing groups, such as brainstorming sessions, believe that the session was more effective than it really was (Larey & Paulus, 1995). People also believe that their group was particularly effective, in comparison to other groups, and that they individually contributed more to the group goal than they really did (Paulus, Dzindolet, Poletes, & Camacho, 1993).

The tendency to overvalue the productivity of groups is known as the illusion of group effectivity. People think groups are more successful than they are in large part because they see the contributions of all of the group members. When we hear many ideas expressed by ourselves and by the other group members, this gives the impression that the group is doing very well, even if objectively it is not.

The illusion of group effectivity poses a severe problem for effective group performance. For one thing, groups may continue to use and to rely on group decision-making procedures even when those procedures are not actually effective. Furthermore, the feeling that the group is producing a lot of good ideas may lead the group to think that it is doing better than it really is. As a result, the group members may erroneously feel that they have been successful at the task and stop working earlier than they should.

One of the most important conclusions to be drawn from the literature that has studied brainstorming is that the technique is less effective than expected because group members are required to do other things in addition to being creative. Variations on brainstorming, such as those that allow group members develop their own ideas as individuals first, before they share them with the group, may be more effective.

Contemporary advances in technology have given individuals the ability to work together on creativity tasks via computer. These computer systems, generally known as group support systems (GSS), are used in businesses and other organizations as well as in classroom settings (Birchmeier, Dietz-Uhler, & Stasser, 2011; Bonczek, Holsapple, & Whinston, 2014). One use of GSS involves brainstorming on creativity tasks. Each individual in the group works at his or her own terminal on the problem. As he or she writes suggestions or ideas, they are passed to the other group members via the computer network so that each individual can see the suggestions of all of the group members, including his or her own.

Electronic brainstorming can be effective because it reduces the production blocking that occurs in face-to-face groups and at the same time allows individuals to benefit from the ideas expressed by others (Nijstad, Diehl, & Stroebe, 2003). Each individual has the comments of all of the other group members handy and can read them when it is convenient. The individual can alternate between reading the comments of others and writing his or her own comments and so is not required to wait to express his or her ideas. In addition, electronic brainstorming can also be effective because, particularly when the participants’ contributions are anonymous, it reduces evaluation apprehension.

Group Polarization

It is possible to predict the results of a group decision from knowledge of member opinions prior to discussion. This is because group decision-making is based in large part on conformity. But it is commonly found that groups make even more extreme decisions, in the direction of the existing norm, than we would predict they would, given the initial opinions of the group members. Group polarization is said to occur when, after discussion, the attitudes held by the group members are more extreme than they were before the group began discussing the topic (Zhu, 2013).

Group polarization does not occur in all groups and in all settings but tends to happen when two conditions are present. First, the group members must have an initial leaning toward a given opinion or decision. If the group members generally support liberal policies, their opinions are likely to become even more liberal after discussion. But if the group is made up of both liberals and conservatives, group polarization would not be expected. Second, group polarization is strengthened by discussion of the topic among the group members before the group reaches its decision. When the group members initially lean in one direction, the conversation will naturally support this leaning, and repeated, persuasive arguments can produce group polarization (Brauer & Judd, 1996; Burnstein & Vinokur, 1975).

Group polarization is also caused in part by diffusion of responsibility—when risky decisions are made by groups, the potential negative consequences are diffused throughout the group so that no one member may be seen to be responsible. Group members’ desires for social identity also can increase group polarization, particularly when the group wants to differentiate itself from other groups with other opinions (Hogg, Turner, & Davidson, 1990; Mackie, 1986). The members of groups who have experienced group polarization may be unaware that polarization has occurred (Keating, Van Boven, & Judd, 2016).

Group Member Diversity

There are some potential advantages for groups in which the members share personalities, beliefs, and values. Groups that are similar in terms of their personality characteristics work better together and have less conflict among the group members, probably at least in part because they are able to communicate well and to effectively coordinate their efforts.

However, although similarity among the group members may be useful in some cases, groups that are characterized by diversity among the members, for instance in terms of personalities, experiences, and abilities, might also have some potential advantages. Diverse interests, opinions, and goals among the group members, assuming that people are willing to express them, may reduce tendencies toward conformity and groupthink by providing a wider range of opinions. Diverse groups may also be able to take advantage of the wider range of resources, ideas, and viewpoints that diversity provides, perhaps by increasing discussion of the issue, therefore improving creative thinking.

However, although diversity may have at least some benefits for groups, it also creates some potential costs. One difficulty is that it may be harder for diverse groups to get past the formation stage and to begin to work on the task, and once they get started it may take more time for them to make a decision. More diverse groups may also show more turnover over time, and group diversity may also produce increased conflict within the group. Furthermore, if there are differences in status between the members of the different ethnic or gender groups (such as when men have higher status than women), this may lead members of the group with lower status to feel that they are being treated unfairly and that they do not have equal opportunities for advancement, which may produce intergroup conflict. Problems may also result if the number of individuals from one group is particularly small. When there are only a few (token) members of one group, these individuals may be seen and treated stereotypically by the members of the larger group. Taken together, then, although diverse groups may have some advantages, the positive effects of group diversity seem to be small (Eagly, 2016; Horwitz & Horwitz, 2007; van Dijk, van Engen, & van Knippenberg, 2012).

Improving Group Process

Because group process is such an important determinant of group performance, increasing group productivity frequently involves teaching and motivating the group members to work together well and efficiently. Effective group performance is not necessarily natural; groups need to learn how to go about their tasks most efficiently, and the group members need to learn how to get along with each other. Table 5 presents some of the variables that are known to improve group productivity.

Table 5. Methods for Improving Group Process

Individual incentives

Rewarding individual group members for performance can be effective but may create comparisons among the group members, which can disrupt group harmony.

Group incentives

Providing incentives for group performance may be useful, although they may lead to social loafing.

Task interest

Making the group tasks more interesting will improve group member satisfaction and performance.


Although too much planning time can be wasteful, spending at least some time in planning before beginning the task performance itself can have positive outcomes on decision-making.

Breaking inefficient norms

Groups frequently develop norms that hinder productivity. Interventions that address these issues and provide new norms can be effective.

Goal setting

Groups that set specific, difficult, and yet attainable goals (for instance, “improve sales by 10% over the next six months”) are much more effective than groups that are given goals that are not very clear (“let’s sell as much as we can!”; Locke & Latham, 2013).

What Are the Benefits of Groups?

In summarizing the results of group performance on decision-making and task performance, we can say, first, that groups influence performance primarily through their effects on the amount of effort that individuals put into the task and secondarily through effects on the ability of groups to coordinate their efforts. Process losses are generally more common than process gains. Individuals frequently withdraw effort when they are in groups, and this reduces task performance. Indeed, social loafing is so common that is has been referred to as a type of “social disease” that has “negative consequences for individuals, social institutions, and societies” (Latané et al., 1979, p. 831).

This does not mean that groups are never useful and that people should always make their decisions alone. Groups are a necessary and important part of successful task performance, and it is worth considering this fact more fully.

The Advantage of Numbers

Because groups consist of many members, group performance is almost always better, and group decisions generally more accurate, than that of any individual acting alone. Presidents have advisors, and corporations have boards of directors precisely because groups have a real advantage over individuals—many heads are better than one, in terms of knowledge, memory, and ability more generally, and (although group process can sometimes cause problems) this should always be kept in mind.

In general, it might expected that larger working groups are more efficient and productive than smaller groups because of the increased energy and expertise that larger numbers of individuals bring with them. On the other hand, larger groups are also more likely to suffer from coordination problems, such as difficulties in communication and time management and motivation losses. It turns out that the most effective working groups are relatively small—about four or five members. Research suggests that in addition to being more efficient, working in groups of about this size is also more enjoyable to the members, in comparison to being in larger groups.

Evaluation Potential and Identifiability

As seen in the discussion of social facilitation, one type of process gain occurs when groups perform easy or well-learned tasks. These gains are particularly likely when the individuals in the situation are aware of each other’s performance, and thus the performance is both identifiable and likely to be evaluated. On the other hand, process losses are more likely to be observed in tasks in which the individual’s inputs are perceived as nonidentifiable or nonessential, because in these cases motivation to perform the task generally decreases. Overall, then, groups are particularly effective when the group members are also working as individuals—that is, when members are aware of, and able to monitor, each other’s inputs (Baumeister, Ainsworth, & Vohs, 2015).

Process Gains?

Drawing from the findings in the social facilitation literature, as well as from our understanding of group processes more generally, we might expect that process gains would occur primarily in groups that have a lot of experience working together and that are well trained for the task that they are performing. For these groups, the presence of others should produce an increase in the dominant response—which in this case is the correct one—and these groups should also be well able to coordinate their efforts. The group from NASA that worked together to land a human on the moon, a rock band that is writing a new song together, or a surgical team in the middle of a complex operation may coordinate their efforts so well that is clear that the same outcome could never have occurred if the individuals had worked alone or in another group of less-well-suited individuals. In these cases, the knowledge and skills of the individuals seem to work together to be effective, and the outcome of the group effort appears to be enhanced.

There is at least some research evidence for process gains in groups (Weber & Hertel, 2007). For instance, in one study, Michaelsen, Watson, and Black (1989) had groups of students first take a multiple-choice test alone and then work together in groups to complete the same test. The average test score for individuals was 74.2%, and the average score of the best member in each group was 82.6%, whereas the average score for groups was 89.9%. Similarly, Laughlin, Hatch, Silver, and Boh (2006) found that groups of three or more members solved complex letters-to-number problems more efficiently and more accurately than did individuals or people working in pairs, and Liang, Moreland, and Argote (1995) found that groups that were trained together to perform a task subsequently performed better together than groups made up of members who had been trained individually. Thus, although the gains may not be as large as might be expected, under some limited conditions process gains may be possible (but see Tindale & Larson, 1992a, 1992b).

Process gains are particularly likely to be found on conjunctive tasks in which weaker group members realize that they are not contributing as much as others are and therefore become motivated to match the higher productive norms of the group (Kerr & Hertel, 2011). At least in some cases, this realization creates upward social comparison in which the weaker group members try to match the behavior of others by working harder. Social support in the form of encouragement from other group members can also be helpful (Hüffmeier et al., 2014).

Implementing Decisions

Although the study of group process focuses on how groups make good decisions, the group must also be able to implement the decision once it is made by getting the relevant people to accept the decision and to act upon it. The group members are more likely to accept the decision if they perceive that the process that led to the decision was fair and impartial. Allowing plenty of opportunity for group discussion is important in this regard, because it allows group members to express their opinions and increases the likelihood that they will perceive that the decision was fair and that their own opinions were considered. Decisions based on a unanimity decision scheme (rather than majority rule, for instance) are likely to produce greater group satisfaction, particularly on matters that are of high importance to the group, once the decision has been made.

Finally, even if group performance is not as good as we might hope, in comparison to that of individuals, working in groups may still produce other positive outcomes. For one, the social identity that results from group membership may inspire individuals to make personal sacrifices that they might not have made had they not been part of the group. The extraordinary performances of humans in wars, on sports teams, and in emergency situations are frequently driven in part by group membership and the social identity that group membership creates.

Finally, people prefer group decisions because they are perceived as being democratic and fair. We have more confidence in decisions made by groups rather than by individuals because group decisions give people a “voice” or sense of ownership in the decision. As a result, collective decisions are more easily accepted by others and produce a greater commitment on the part of the group members to reach the relevant goals.


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