Majority influence

Will people conform to a majority group opinion even when that opinion is obviously incorrect?

What factors affect conformity?

Is conformity a product of the social and political climate at the time?
Will people conform to majority influence even when the group is obviously wrong?

Asch (1951) - the line experiment
Early studies into conformity, such as Sherif’s auto kinetic effect experiment, had used stimuli that were ambiguous and so it could be argued that participants conformed because they were unsure as to the correct answer and so went along with the information provided by the other participants in the group. This means it was impossible to know whether or not participants had actually rejected their own initial opinions (e.g. how far they estimated the point of light moving in Sherif, 1935) in favour of the information provided by the group. To answer this, Asch designed an experiment to test conformity in a situation where the correct answer was obvious.

Asch recruited 123 male students from Swarthmore College in the USA to participate in a ‘vision test.’ They were divided into groups of 5 to 7 people in which, unknown to the participants, all but one of them were confederates of Asch and followed his instructions. In other words each group consisted of 4 to 6 confederates and 1 naive participant.

Each group was shown a set of 3 lines and a separate reference line, and group members had the task of simply stating which line was the same length as the reference line. Each set of lines consisted of one line that was obviously the same length as the reference line, and two that were obviously different. Group members gave their answer one after the other, and the real participant gave his answer in next to last place. Each group performed the task 18 times (18 trials). On the first 2 trials the confederates answered correctly, but for 12 of the remaining 16 trials they answered incorrectly. These 12 trials were the ‘critical trials’ in the experiment.

Asch line experiment

The results of Asch’s experiment were astonishing considering that the stimuli used consisted of unambiguous lines in which participants must have know the correct answer.
  • Participants conformed to the obviously incorrect answer given by the group majority on 32% of critical trials.
  • 74% of participants conformed to the incorrect group majority at least once.
  • Only 25% of participants did not conform at all.


Factors affecting conformity
Variations on Asch experiment
Asch further investigated the precise factors that influence conformity by varying factors in his experiment:
  • Size of the majority. When the group size was reduced to just two (one confederate) there was almost zero conformity. A majority of two confederates yielded a small degree of conformity, and groups with three or more confederates produced the highest rates of conformity. This shows that groups with a majority of three or more people are sufficient to cause conformity even when the correct answer is obvious.
  • Unanimity of the majority. Asch repeated the initial experiment but this time he instructed one of the confederates (usually the 3rd or 4th to answer) to go against the majority and give the correct answer. In this situation conformity rates dropped and the real participant was less likely to conform to the obviously incorrect answer. The presence of another group member going against the majority opinion (a dissenter) lends social support, and other group members are less likely to feel alone and are more likely to stick to their own opinion. However, when the dissenting confederate wore glasses the reduction in conformity was less noticeable, perhaps because the opinion of a group member with eyesight difficulties was less valid in a task that required a visual judgement to be made.
  • Nature of the task. When the task was made more difficult (by making all three lines more similar to the reference line) then conformity rates increased. This shows that when a task is more difficult, individuals are more likely to refer to the majority opinion and so conformity is more likely.


Evaluating Asch
Criticisms of Asch line experiment
  • Conformity rate was only 32%. Asch reported the results of his study as an astonishing rate of conformity with participants conforming to an obviously incorrect answer in 32% of critical trials. However that failed to acknowledge that in 68% of critical trials there was no conformity, and so perhaps the study was more a measure of factors that lead to resisting a majority rather than those that make conformity more likely.
  • Socio-political context. In 1950s USA there was a culture of paranoia against communism and left wing views. The era was termed McCarthyism and left wing protagonists were ostracised by the ultra conservative government. Such a culture is likely to breed a fear of nonconformity and make conformity more likely, so the study may have been measuring political feeling and fears at the time rather than the human tendency to conform - see child of its time (below).
  • Population validity. The participants were all young male students from the same American university. This meant the results were not generalisable outside of the population sampled and did not apply to anyone other than male American college students.
  • Ecological validity. Judging the length of lines is not really an everyday task that people regularly participate in.
  • Ethical considerations. Participants were deceived into believing they were taking part in a ‘vision test’ and were not informed that it was a study of conformity. Not gaining informed consent is a breach of ethical guidelines, however very different results would have been produced had participants known the true nature of the study and so it could be argued that deception was necessary.

A child of its time (Perrin & Spencer, 1980)
To further investigate the criticism that conformity in the Asch line experiment was due to the socio-political context of 1950s America, and therefore a ‘child to its time’, Perrin & Spencer (1980) repeated the experiment with British university students on science and mathematics courses, and found far lower rates of conformity than those reported by Asch. They then repeated the experiment again, but this time with participants who were young offenders and confederates who were recruited from probation officers, and found similar rates of conformity to the original Asch experiment.

As British students who were used to making judgements about the physical properties of things conformed less, and British young offenders who perhaps were unwilling not to conform because they feared sanctions from their probation officers were more likely to conform, then Perrin & Spencer concluded that the social and political situation people are in has a considerable influence on their tendency to conform. The Asch line experiment is, therefore, a ‘child of its time.’


A Level exam tips
Answering exam questions (PSYA2 AQA A specification)
Outline and evaluate research into majority influence (12 marks)
6 AO1 marks come from describing the aim, procedure, results and conclusion of the Asch line experiment.

6 AO2 marks can come from a wide variety of evaluation points. As only 6 marks are required, it is not necessary to include absolutely everything. Choose three evaluations and explain them well.









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