Difficulty: Intermediate | Prerequisites: Social Identity Theory, free-rider problem (Week 14), Emotions (Week 9).
This final topic covers how groups function: what makes a collection of people a "group" (interdependence), the three types of interdependence, two emergent decision-making problems (groupthink and group polarisation), deindividuation, the social facilitation/interference distinction, social loafing as a free-rider variant, and the role of leadership. This ties together themes from the entire course.
A group is distinguished from an arbitrary collection of people by relational interdependence. Three types of interdependence (pooled, sequential, reciprocal) produce different strengths and vulnerabilities. Groups strive for cohesion and harmony, but this creates two maladaptive decision-making phenomena: groupthink (self-censoring to preserve consensus) and group polarisation (discussion amplifying average views into extreme positions). Social facilitation improves performance on well-learned tasks in the presence of others, while social interference impairs performance on novel tasks. Social loafing (reduced effort when only group outcomes are assessed) is a variant of the free-rider problem. Leadership can counteract these dynamics by establishing roles and reciprocal interactions.
Group (social psychology definition)
A collection of individuals who have relations to one another that make them interdependent to some significant extent. In simple terms, not just any three people standing together, but people whose outcomes depend on each other.
Interdependence
Some form of exchange or mutual reliance in a social domain. The defining feature that makes a collection of people a group.
Pooled Interdependence
Interdependence characterised by shared resources and outcomes but no structure or roles. Low conflict but often ineffective.
Sequential Interdependence
Interdependence involving an asymmetrical chain of one-way interactions, where later stages depend heavily on early stages.
Reciprocal Interdependence
Interdependence involving expectation-governed interactions between multiple specialised roles. Vulnerable to poor coordination.
Groupthink
The overall reduction in critical scrutiny and consideration that occurs when members of a group are reluctant to risk group cohesion by expressing disagreement. Related to the false consensus effect and pluralistic ignorance. In simple terms, everyone goes along with a bad idea because nobody wants to be the one to object.
Group Polarisation
The tendency for groups to endorse more extreme courses of action than any single member would endorse in private. Formerly called "risky shift."
Deindividuation
The reduction in distinctness of our sense of self when acting in a group, generally associated with lowered inhibitions.
Social Facilitation
Improved performance in the presence of others. Studied in two forms: co-action effects (others doing the same activity) and audience effects (passive spectators).
Social Interference
Impaired performance in the presence of others. Related to Mere Presence Theory, distraction-conflict theory, and evaluation apprehension theory.
Social Loafing
Reduced motivation to perform when only group outcomes are assessed, reducing actual output. A variant of the free-rider problem and the Tragedy of the Commons.
Normalisation (in group polarisation)
When groups are homogeneous, constant exposure to similar perspectives in an "echo chamber" causes members to lose perspective on what wider alternatives exist.
Value Affirmation
Expressing extreme attitudes as a way to signal loyalty to the group. A contributor to group polarisation.
A group is more than any arbitrary set of three or more people. It is "a collection of individuals who have relations to one another that make them interdependent to some significant extent."
Interdependence is the defining feature: some form of exchange or mutual reliance in a social domain.
Three categories of interdependence:
Pooled: shared resources and outcomes, no structure or roles. Low conflict but often ineffective.
Sequential: asymmetrical chain of one-way interactions; later stages depend on early ones.
Reciprocal: expectation-governed interactions between specialised roles. Vulnerable to poor coordination.
Even casual social groups operate interdependently around implicit goals, striving for intra-group cohesion and harmony.
The need for cohesion and harmony creates psychological pressure that conflicts with good deliberation, producing two emergent phenomena:
Groupthink: the most common maladaptive group-level phenomenon. When a group must decide by consensus, members self-censor to avoid damaging cohesion. This reduces critical scrutiny. Related to:
False consensus effect: assuming everyone agrees with you
Pluralistic ignorance: everyone privately disagrees but assumes everyone else agrees
Group Polarisation: discussion can magnify average views into more extreme positions. Formerly called "risky shift." Driven by:
Normalisation: echo-chamber exposure eliminates awareness of alternatives
Value Affirmation: expressing extreme attitudes signals group loyalty
Deindividuation: the reduction in distinctness of self when acting in a group, associated with lowered inhibitions.
The Stanford Prison Experiment illustrates diffusion of responsibility.
Should we worry about "losing ourselves" in large group actions? Not especially; it is the standard trade-off of Social Identity Theory.
Social Facilitation: performance improves in the presence of others. Two forms:
Co-Action Effects: changes in behaviour caused by others simultaneously doing the same activity
Audience Effects: changes in behaviour caused by passive spectators
Social Interference: performance is impaired in the presence of others.
Mere Presence Theory: the mere presence of others causes heightened physiological arousal
Evolved into distraction-conflict theory, then modern evaluation apprehension theory
What determines whether facilitation or interference occurs: primarily whether the task is well-learned (improved by arousal) or novel (harmed by distraction), and whether there is fear of credible judgement/evaluation.
When only group outcomes are assessed, motivation to perform drops, reducing actual output.
A variant of the free-rider problem and the Tragedy of the Commons.
Classic example: tug of war (individual effort decreases as group size increases).
The larger the group, the greater the diffusion of responsibility.
Leadership allows a group to employ an individual's decision-making instead of the emergent (and often flawed) decision-making of the group.
Beneficial under circumstances where group dynamics leave the group vulnerable to bad outcomes (groupthink, polarisation, social loafing).
Effective leadership counteracts social loafing by establishing roles and reciprocal interactions, boosting accountability.
Students often confuse groupthink with group polarisation. Groupthink is about self-censoring to preserve consensus (the group makes a mediocre or bad decision because nobody objects). Group polarisation is about discussion amplifying average views into more extreme positions.
Social facilitation does not always improve performance. It improves performance on well-learned tasks and impairs it on novel ones. The "facilitation" in the name refers to the most-studied case, not a universal effect.
Social loafing is not laziness. It is a rational (if maladaptive) response to a situation where individual effort is invisible and only group outcomes are measured.
⚠️ Know the three types of interdependence (pooled, sequential, reciprocal) and what each is good and bad at.
⚠️ Be able to distinguish groupthink from group polarisation.
⚠️ Know the conditions that determine facilitation vs. interference (well-learned vs. novel task).
⚠️ Social loafing as a free-rider problem and Tragedy of the Commons variant.
⚠️ How leadership reduces social loafing (shifts pooled to reciprocal interdependence, establishes accountability).
⚠️ The five main themes of the course: Humans are Social Animals, Biological and Cultural Coevolution, Theory-Laden Observation, All Behaviours Are Interpreted, The Power of the Situation.
Fill in the blank: The defining feature that distinguishes a group from an arbitrary collection of people is ______. (Relational interdependence.)
True or False: Groupthink leads groups to endorse more extreme positions. (False. That is group polarisation. Groupthink leads to uncritical consensus.)
Fill in the blank: Social facilitation improves performance on ______ tasks. (Well-learned.)
True or False: Social loafing increases as group size decreases. (False. It increases as group size increases, due to diffusion of responsibility.)
Fill in the blank: The three categories of interdependence are pooled, sequential, and ______. (Reciprocal.)
Q: What interpersonal element meaningfully distinguishes a group from an arbitrary collection of people?
A: Relational interdependence.
Q: What are the three categories of interdependence used in organisational psychology?
A: Pooled, Sequential, and Reciprocal.
Q: What are two bad emergent phenomena in group decision-making?
A: Groupthink and Group Polarisation.
Q: What is Groupthink?
A: The relative suspension of critical insights when making a consensus-based decision; people self-censor to avoid damaging group cohesion.
Q: What is Social Facilitation?
A: Performing better at a task due to the social presence of others.
Q: What determines whether Facilitation or Interference will happen?
A: Primarily whether the task is well-learned (improved by arousal) or novel (harmed by distraction), and fear of credible judgement/evaluation.
Q: What is Social Loafing?
A: When people acting in groups work less hard than when they are alone.
Q: How can directed leadership reduce Social Loafing?
A: Social Loafing thrives in pooled interdependence. Effective leadership establishes roles and reciprocal interactions, boosting accountability.
This connects to Week 14 (Helping and Cooperating) because social loafing is a variant of the free-rider problem and Tragedy of the Commons. It connects to Prejudice (Week 13) because groupthink and polarisation in homogeneous groups can amplify prejudiced attitudes. It connects to Emotions (Week 9) because the social facilitation/interference distinction depends on autonomic arousal.
Group dynamics, groups, interdependence, pooled interdependence, sequential interdependence, reciprocal interdependence, groupthink, false consensus effect, pluralistic ignorance, group polarisation, risky shift, normalisation, value affirmation, deindividuation, diffusion of responsibility, Stanford Prison Experiment, social facilitation, co-action effects, audience effects, social interference, Mere Presence Theory, evaluation apprehension, social loafing, free-rider problem, Tragedy of the Commons, leadership, PSY 301, social psychology, NYU