Group polarization

Group polarization is the tendency for discussion among like-minded people to move their judgments toward a more extreme version of their initial average inclination.

Persuasive arguments theory: A theory that explains attitude change through exposure to arguments favoring one position. Discussion supplies additional arguments that support the group’s initially dominant inclination.
Moscovici–Zavalloni study: A study showing that discussion made French students’ attitudes toward political figures and the United States more extreme. Its results established that polarization extended beyond choices involving risk.
Deliberative democracy: A model of democracy that gives public reasoning and discussion a central role in legitimate decision-making. Polarization raises the question of whether deliberation broadens judgment or hardens prior positions.
Group conformity: The adjustment of judgments or behavior to match a group’s standards or members. Conformity means moving toward the group; polarization specifically means movement toward a more extreme position.
Social comparison theory: A theory that people evaluate themselves by comparing their opinions and behavior with those of others. Members may adopt stronger positions to appear favorably aligned with perceived group norms.
James Stoner: A researcher whose 1961 thesis documented the risky shift in group decisions. His decision-dilemma experiments helped launch research into group-induced attitude change.
Echo chamber: An environment where people encounter information and opinions that largely reinforce their existing views. Repeated like-minded discussion can create conditions in which initial inclinations intensify.
Attitude change: A change in a person’s evaluation of an object, person, issue, or action. Group polarization is one patterned form of attitude change following discussion.
Informational influence: Social influence in which people treat others’ judgments as evidence about what is correct. Hearing others’ reasons can make an initially popular position seem better supported.
Choice dilemma questionnaire: A research instrument asking respondents to recommend a minimum acceptable probability before choosing a risky option. Researchers used these dilemmas to compare private judgments before and after group discussion.

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