Key Study

Asch (1951)

Effect of group pressure on the modification and distortion of judgements

Aims

The aim of Asch’s study was to investigate the extent to which people would agree (conform) when others gave a wrong answer to a task that was obvious and unambiguous. Asch was also interested in the variables that affected the level of conformity.

Procedures

Experiments led by Solomon Asch asked students to participate in a "vision test." In reality, all but one of the participants were confederates of the experimenter, and the study was really about how the remaining student would react to the confederates' behavior.

The participants — the real subject and the confederates — were all seated in a classroom where they were told to announce their judgment of the length of several lines drawn on a series of displays. They were asked which line was longer than the other, which were the same length, etc. The confederates had been prearranged to all give an incorrect answer to the tests.

Findings

Asch’s findings were that was a mean conformity rate of 32% (about 1/3) of the critical trials. About ¾ of all participants conformed at least once. However no subjects conformed on all the critical trials.

Conclusions

Given that the task was simple and ambiguous Asch’s conclusion was that he had demonstrated a very high level of conformity. Participants could be persuaded by group pressure to go against the evidence of their own eyes.

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