Solomon Asch (1951) conducted an experiment to investigate the extent to which social pressure from a majority group could affect a person to conform
Asch used a lab experiment to study conformity, whereby 50 male students from Swarthmore College in the USA participated in a ‘vision test’. Using a line judgment task, Asch put a naive participant in a room with seven confederates.
Each person in the room had to state aloud which comparison line (A, B or C) was most like the target line. The answer was always obvious. The real participant sat at the end of the row and gave his or her answer last. There were 18 trials in total and the confederates gave the wrong answer on 12 trails.
Asch measured the number of times each participant conformed to the majority view. On average, about one third (32%) of the participants who were placed in this situation went along and conformed with the clearly incorrect majority on the critical trials
Over the 12 critical trials about 75% of participants conformed at least once, and 25% of participant never conformed. In the control group, with no pressure to conform to confederates, less than 1% of participants gave the wrong answer.
When they were interviewed after the experiment, most of them said that they did not really believe their conforming answers, but had gone along with the group for fear of being ridiculed or thought "peculiar". A few of them said that they really did believe the group's answers were correct.
Apparently, people conform for two main reasons: because they want to fit in with the group (normative influence) and because they believe the group is better informed than they are (informational influence).
When the comparison lines were made more similar in length it was harder to judge the correct answer and conformity increased. When we are uncertain, it seems we look to others for confirmation. The more difficult the task the greater the conformity
Asch further investigated the factors that affect conformity by varying factors in his experiment.
Asch found that group size influenced whether subjects conformed. The bigger the majority group the more people conformed, but only up to a certain point. With one other personin the group conformity was 3%, with two others it increased to 13% and with three or more it was 32%
As conformity drops off with 5 members or more, it may be that it’s the unanimity of the group (the confederates all agree with each other) which is more important than the size of the group
One limitation of the study is that is used a biased sample. All the participants were male students who all belonged to the same age group. This means that the study lacks population validity and that the results cannot be generalized to females or older groups of people.
Another problem is that the experiment used an artificial task to measure conformity - judging line lengths. How often are we faced with making a judgment like the one Asch used, where the answer is plain to see? This means that study has low ecological validity and the results cannot be generalized to other real life situations of conformity.