Moscovici, S., Lage, E., & Naffrechoux, M. (1969). Influence of a consistent minority on the responses of a majority in a color perception task. Sociometry, 32(4), 365-380
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Moscovici argues that a minority sub-group has the ability to influence the responses of the majority through exhibiting a consistent behavioral style. The experimental procedure that supports this argument was a color perception task where a minority confederate group responded that objectively "Blue" colors were actually "Green". By consistently stating the "Green" case over multiple sessions, the minority confederate group was able to influence the responses and actual color coding perceptions of group majority members.
The field of social influence prior to the publication of this paper focused primarily upon majority influence within groups. The release of this paper was key in establishing minority influence as a legitimate area of intra-group research.