Why Groups Make Great and Terrible Decisions
Lecture Overview: Group Decision-Making Processes
The lecture, presented by Prof Tim Hopthrow, explores the dynamics of how groups make decisions, categorized into three primary inquiries: - Does interaction with groups intensify our decisions? - Does unique knowledge contribute to group decisions? - Do groups make better decisions than individuals?
Group Polarization and the Risky Shift
Part 1 Question: Does interaction with groups intensify our decisions?
Group Polarization Definition: A tendency for group discussions to produce more extreme group decisions than the individual members' pre-discussion opinions or the direction originally favored by the mean.
Risky Shift (Stoner, 1961): - In this study, individuals initially marked their answers alone. - After discussing opinions with a group, they marked their answers again. - Findings: Groups consistently made riskier decisions than individuals. The group consensus shifted toward a "riskier" position than the average decision made by individuals prior to the discussion.
Re-conceptualization (Moscovici & Zavalloni, 1969): - Proposed that the "Risky Shift" is not specifically about risk, but is a general phenomenon related to the group's initial leanings. - Group Polarization: Group discussion strengthens the average inclination of the members.
Moscovici & Zavalloni (1969) French Student Study: - Examined attitudes toward Americans (initially negative) and toward General de Gaulle (initially positive). - Post-discussion results: - Attitudes toward Americans became even more negative. - Attitudes toward de Gaulle became even more positive. - Data trends showed a shift from initial scores (approx. for Americans and for de Gaulle) to more extreme scores (approx. and respectively).
Further Evidence: Brauer, Judd, & Jacquelin (2001) found that mutual dislike for peers increased when students shared those views with one another.
Mechanisms of Group Polarization
1. Normative Influence (Social Comparison): - Driven by the desire for public approval. - Individuals adjust their views to more extreme positions to fit in or be seen favorably by the group.
2. Informational Influence (Persuasive Argument): - Verbalizing ideas that support the dominant opinion reinforces belief in that opinion. - Hearing new persuasive arguments in favor of the dominant view further polarizes beliefs.
3. Self-Categorization Theory: - Identifying as a group member leads individuals to take on the identity of intergroup behaviors.
The "Groupdrink" Study
Are groups always risky? Research by Abrams, Hopthrow, Hulbert, and Frings (2006) examined risk orientation under the influence of alcohol.
Study Design: Evaluated risk orientation in groups vs. alone, and after consuming alcohol vs. a placebo.
Findings: - Main effect of alcohol/placebo: Alcohol lead to higher risk attraction than the placebo (Alcohol > Placebo). - Main effect of group/individual: None found. - Significant interaction effect: For individuals, alcohol increased risk significantly (from approx. to ). However, for groups, the increase in risk from placebo to alcohol was much smaller (approx. to ). - Conclusion: This supports the idea of "group monitoring"; groups may exercise more caution or monitoring when members have been drinking compared to individuals.
The Hidden Profile Problem
Part 2 Question: Does unique knowledge contribute to group decisions?
Basic Concept: Groups possess collective shared knowledge and unique individual knowledge.
Theoretical Perspective (Stasser & Titus, 1985, 1987): Initially suggested that unique and novel arguments should be the most persuasive in decision-making groups.
Empirical Reality (The Hidden Profile Problem): Groups generally focus on information shared by all members rather than information uniquely held by individuals (Stasser & Titus, 1985, 1987, 2003).
Key Characteristics: - Groups over-focus on common insights and fail to discuss unique information (Strasser, 1992). - Even when shared, unique information is often not heard, understood, or integrated (Dennis, 1996; Kerr & Tindale, 2004; Larson et al., 1994). - This failure leads to lower quality decisions.
Factors Causing the Hidden Profile
Time Pressure: High urgency for closure makes participants less receptive to diverging perspectives, though they become more task-focused (Kruglanski & Webster, 1991; Karau & Kelly, 1992).
Group Size: Larger groups increase the likelihood of overlooking unique ideas (Steiner, 1972). - In a -person group: Each individual has a chance to contribute unique info. - In a -person group: Each individual has a chance to contribute unique info.
Diversity: Greater diversity can lead to intergroup stereotypes and conflicts that compromise member resources (Caruso & Woolley, 2008).
Composition Shifts: Frequent changes in group membership make it hard to track who has specific expertise (Lewis et al., 2007).
Technology/Dispersion: Geographically dispersed groups relying on electronic communication struggle to determine "who knows what" (Nemiro et al., 2008).
Social Costs & Status: - High-status members (e.g., resident physicians) are more likely to discuss unique info than low-status members (e.g., interns/students) due to credibility concerns for the latter (Larson et al., 1996; Stewart & Stasser, 1995).
Strategies to Overcome Hidden Profiles
Groups must recognize members with special expertise (Bauman & Bonner, 2004).
The group must value individual contributions (Caruso & Woolley, 2008).
Motivation and coordination are required to utilize resources (Quigley et al., 2007).
Ensure equal status among members (Hollingshead, 1996).
Use common dimensions for comparison (e.g., ranking decisions rather than choosing outright) (Reimer et al., 2007).
Brainstorming in Groups
Part 3 Question: Do groups make better decisions than individuals?
Definition: The generation of novel ideas where members generate as many ideas as possible, as quickly as possible (Osborn, 1957).
Effectiveness: Diehl and Stroebe (1987) found little evidence that group brainstorming is more creative than individual brainstorming.
Exceptions & Nuances: - Eyewitness testimony is more accurate as a group account (Warnick & Saunders, 1980). - Groups produce better quality ideas when they critique each other (McGlynn et al., 2004).
Factors hindering brainstorming (Paulus et al., 1993): - Evaluation apprehension. - Social loafing and free riding. - Production matching (matching the low output of others). - Production blocking (forgetting ideas while others speak).
Improving Brainstorming: - Combine individual and group sessions (Brown & Paulus, 2002). - Use written communication (Mullen et al., 1991) or electronic brainstorming (Gallupe et al., 1994). - Use heterogeneous groups with diverse backgrounds (Stroebe & Diehl, 1994).
Illusion of Group Effect: People believe groups are better because a group generates more total ideas than any single individual, even though an equal number of individuals working alone generate more total ideas than the group (Diehl & Stroebe, 1991).
Group Memory and Transactive Memory
Group Memory: Groups generally remember more than individuals (Clark & Stephenson, 1989, 1995). Logic suggests they recognize true information when heard (Lorge & Solomon, 1995).
Complexity Factor: Steiner (1976) noted groups excel at simplistic artificial tasks (e.g., nonsensical words) more than complex realistic tasks (e.g., a story).
Transactive Memory (Wegner et al., 1991): - A shared system for encoding, storing, and retrieving information that exists only within a group. - Example: A psychology department or a couple where different individuals are responsible for different domains (e.g., car insurance vs. domestic chores).
Group Mind (McDougall, 1920): Theory that people adopt a qualitatively different state of mind when in a group.
Stability in Transactive Memory (Argote et al., 1995): - Study involved people in groups of learning origami. - Performance dropped as members left; newcomers did not improve performance because they hadn't learned with the group.
Groupthink
Definition (Janis, 1972): A desire to reach a unanimous decision that overrides the motivation for a rational decision-making process.
Vulnerability Factors: Similar backgrounds, insulation from outside opinions, and lack of clear decision rules.
Eight Symptoms (Janis, 1971): - 1. Illusion of invulnerability (excessive optimism). - 2. Collective rationalization (discounting warnings). - 3. Belief in inherent morality (ignoring ethical consequences). - 4. Stereotyped views of out-groups (viewing "enemies" as ineffective). - 5. Direct pressure on dissenters. - 6. Self-censorship (doubts are not expressed). - 7. Illusion of unanimity (assuming the majority view is unanimous). - 8. Self-appointed ‘mindguards’ (protecting the leader/group from contradictory info).
Remedies and Critiques of Groupthink
Remedies for Groupthink (Janis, 1982): - Assign a "devil's advocate"/critical evaluator role. - Leaders should avoid stating preferences early. - Discuss deliberations with outside trusted associates. - Invite outside experts to challenge decisions. - Have a "second chance" meeting to discuss lingering doubts.
Critiques: - Research is often retrospective. - Inconsistent findings: while high cohesion can lead to groupthink (Rovio et al., 1996), it doesn't always. Norms of critical thought can lead to correct decisions even in cohesive groups (Postmes, Spears & Cihangir, 2001).