The Asch Study


Key Study:

In 1955, Soloman Asch conducted a series of laboratory experiments to investigate the degree to which individuals would conform to the majority who gave obviously wrong answers.

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Asch wanted to measure the strength of the conformity effect using an unambiguous task.

In the task, the participant has to say which of lines A, B or C matches the stimulus line (x).

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Between seven and nine confederates sat in a line or semicircle.

Asch gave naive participants a seemingly obvious task - to match vertical lines on a card.

On the first two trails the confederates gave the right answers but on the third they gave the wrong answer. 

The dependent variable was who would conform to the confederates and give the wrong answer having heard their answers first.

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  • The naive participants conformed to the wrong answer 36.8% of the time when alone with the confederates over 12 trails; 25% never conformed.
  • There was also a control trial with no confederates to check the task was unambiguous. Mistakes were made 1% of the time - far less than under the experimental condition.
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Some individual's judgements are influenced by majority opinion - even when majority opinion is obviously wrong.

Although 36.8% is not the majority, participants conformed at least once to the majority 75% of the time.

Asch gave three reasons why 36.8% conformed:

  • Distortion of perception - they came to see the lines the same way as the majority.
  • Distortion of judgement - they doubted their judgement and went with the majority.
  • Distortion of action - they agreed in public but not privately (they complied).
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  • Reliability: Asch used a standardised procedure which means that the findings can be replicated, increasing their reliability.
  • Internal validity: There was no ambiguity in the task and therefore he was measuring conformity and not people's ability to percieve small differences in length, giving it internal validity.
  • Because the answers were obvious, Asch's study shows the impact of the majority.
  • External validity: The set-up was artificial and the task an odd thing to be discussing around a table, so it lacks ecological validity or mundane realism.
  • Ethics: The participants were deceived as they thought it was a visual perception task.
  • Bogdonoff et al (1961) found that participants in an Asch-type study had greatly increased levels of autonomic arousal, suggesting they were in a conflict situation possibly causing psychological harm.
  • Perrin and Spencer (1980, 1981) found that engineering students were much less compliant.
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