Asch line experiment

what was the aim

To assess how much people will conform to the opinion of others even in a situation where the answer is certain (unambiguous)

what was the procedure

• 123 male student pps. Each one was place in a room with 6-8 confederates

• Shown a standard line and asked to state aloud which comparison line (A,B or C) was most like the standard line

• the answer was always obvious (unambiguous)

• the confederates began the trails by giving the correct answer but then began to make ‘errors’

• there were 18 trails - 12 were critical trials where the confederates gave the wrong answer

• there was also a control condition where there were no confederates, only ‘real pps’

Asch results

• 75% conformed at least once

• 36.8% went along either way the group on the majority of trails 

• 25% remained completely independent 

• when tested alone, subjects got more than 98% of judgements correct.

conclusion? 

pps reported conforming due to normative social influence - i.e. to avoid rejection

what were the three variations

1. group size

2. unanimity

3. difficulty of tasting 

group size variation?

• tested whether the group size would affect level of conformity 

  • one confederate = 3%

  • two confederates = 13%

  • three or more = 32%

• optimum conformity levels (32%) were found with a majority of 3. 

• increasing the size of group beyond 3 did not increase the levels of conformity found

Variation - unanimity

• is conformity affected if there is dissension in the majority group

• Asch included one confederate who disagrees with the rest

• conformity dropped to 5%

• if group is not unanimous then pps have confidence to disagree 

variation - difficulty of task

• does a difficult task increase or decrease conformity 

• Asch made the comparison lines and the standard lines more similar (more ambiguous)

• conformity increased

• suggests that informative social influence may play a role when a task is ambiguous 

what are the evaluation points

1. Perrin and Spencer

2. limited application - cultures

3. lacking ecological validity

4. Deutsche and Gerrard

evaluation - Perrin and Spencer

P: one critique of Asch’s study is that people today would not react in the same way and would be much less likely to conform

E: this was shown in Perrin and Spencer’s replication of Asch which was conducted in the UK using engineering students

E: There was a significant reduction in conformity with only 1 of 396 pps conforming

L: this shows that the original study lacks temporal validity as conformity displays was not consistent 30 years later. This may be due to a shift in social norms and different political context

evaluation - limited application cultures

P: Much of early research into conformity used pps from a small demographic of the population

E: For example, Asch used all male students from an individualistic culture (US) in his research

E: This is not ideal as there may be gender difference in conformity, similarly we would not expect cultural differences with collectivist cultures being more conformist as the group is more important to the individual

L: For this reason it is difficult to generalise data collected from this group to females, to collectivist cultures, to non-students etc meaning it has limited application

evaluation - lacks ecological validity

P: the research of Asch should be criticised for lacking ecological validity

E: the task set would have been novel to the pps as people would rarely be asked to judge line lengths 

E: therefore their behaviour would probably have been less natural than if the task were a more mundane one such as Schultz’ where pps were measures on recycling behaviour

L: this reduces the application of the research and means that the behaviour observed may have been affected by the unusualness of the task set

evaluation - Deutsche and Gerrard

P: Deutsche and Gerrard’s study adds validity to Asch research by showing how is pps were experiencing normative social influence 

E: In this variation of Asch, they asked pps to write their answers down and then throw the paper away

E: conformity dropped to 5% in this variation which had a similar target population as Asch and was carried out at a similar time (1955)

L: this shows that individuals in Asch were conforming due to the desire to be liked rather than the desire to be right as when answering privately they gave the obvious right answer.