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Why people conform: The Two Process theory


Conformity is something that both you and I do more often than we care to realise. Just think of your day, and how many times you have conformed. What did you think about when you were deciding what to wear? Did you brush your teeth? Did you eat your cereal out of a bowl? You sat on a chair, and not the floor on the bus, right? There are so many ways we conform daily, without giving them a second thought. But why do we do it?

There have been many proposals, one of which being the Two Process theory by Deutsch and Gerard (1955). They claimed that conformity can depend on two things - informational social influence (ISI), and normative social influence (NSI). The theory tried to identify factors responsible for majority influence, however not so much for minority influence due to the fact that in 1955 there had been very little research into minority influence.

Informational social influence:

This focuses on our desire as human beings to be correct. In situations where we are unsure as to how to behave, we look to others to decide. For example, say you are invited to a posh dinner party, but you are unsure as to what you should wear, it is likely you will ask your friends what they are going to wear and go with something similar - by doing this, you are showing informational social influence.Conformity is based on our dependence on others as a source of information.

This type of influence is shown in Sherif's 1935 study into conformity. The influence often leads to a change of opinion in private as well as public terms, indicating the type of conformity as Internalisation. This type of influence is most likely when a situation is ambiguous or is a crisis; this is because these are situations in which people are most likely to doubt their own knowledge and/or intelligence. It also occurs when there are experts in the picture, as we are highly likely to believe they know better than we do, therefore we seek their opinion and knowledge in order to get things 'right'.

Sherif 1935 - Did a research study to demonstrate why people conform, and it was one of the first major studies of conformity. He used the autokinetic effect (a visual ilusion where a small spot of light in a darkened room appears to be moving when it is in fact stationary).

His key condition - Participants were tested one at a time, and then in groups of three.

Participants were asked to say how much the light seemed to move, and in what direction. Each individual rapidly developed their personal norm. This norm was stable but it varied considerably between individuals, and when three individuals with very different personal norms were then put together into a group, they tended to make judgements that were very close to each other.

The fact that a group norm rapidly replaced personal norms indicates the importance of social influence. Sherif also used a condition in which individuals started the experiment in gorups of three, and were then tested on their own. Once again, group norms appeared, and then when tested on their own, the participants' judgements concerning the movement of the light continued to reflect the influence of the group!

However, you could argue that the results are not surprising as there was never any way to know what the 'right' answer was, so it made sense to use others as a source of information and take into account their views. The situation was ambiguous, unusual and unlike real life (some argued!) - however there are events in real life when we aren't sure of the answer and so turn to others for information therefore it could be argued that it reflects real life well, and has mundane realism.

Informational social influence has been less extensively studied than the role of normative social influence, however there are some key studies:

Wittenbrink and Hely (1996) - in this study, the participants were exposed to negative comparison information about African Americans, which they were lead to believe was the view of the majority. When it was investigated later on, the participants reported more negative beliefs about a black target invididual. They had not known how to react to the negative comparison information, but being informed that the majority supported it, they too, adopted (somewhat) the views.

Fein et al (2007) - in this study, the role of information social influence in political opinion was investigated, and it was demonstrated how judgements of candidate performance in the US presidential debates could be influenced simply by the knowledge of other people's reactions. The participants were able to see what was supposedly the reaction of fellow participants on a screen during a debate. It produced large shifts in participants' judgements of the candidates' performances. This demonstrates the power of informational social influence in shaping opinion.

Normative social influence:

This idea suggest that a person conforms because of their need to be accepted by, and to belong to the group. This may be because belonging to a group is often rewarding to the individual, and the group has the power to punish or even exclude those who do not fit in. This influence may cause the individual to personally, and privately continue to stick to their individual opinion, however conform with the group on the surface. This is known as compliance. This type of influence is shown in Asch's conformity experiement.

Asch (1951) - The aim was to investigate if people would conform with a majority who were clearly wrong in their judgements.

He took 123 male students and asked them to take part in a 'task of visual perception'. He place them in groups of between 7 and 9 and seated them around a large table. The experimenter then showed them two cards, one of a standard line, and the other showing three comparison lines, A B and C. The participants had to choose which line, A B or C matched the standard line on the other card. The answer was easy and obvious. There were a total of 18 trials for each group. Asch used confederates who were instructed to give the same wrong answer in 12 out of 18 trials (critical trial). In 6 they gave the incorrect answer of the longer line, and in 6 the incorrect answer of the shorter line. The real participant was seated either last or second to last around the table (so that they were exposed to the same wrong answer repeatedly before giving their answer).

Asch found that the overall conformity rates were around 1 in 3. 1 in 20 conformed on every critical trial. 25% remained completely independent. The participants claimed, afterwards, that they doubted their eyes, and others simply didn't want to stand out. As trials progressed, participants became more anxious and self concious, and some reported stress.

The experiment was highly controlled with the number of people, use of confederated etc, so it can establish cause and effect. However, it may lack validity because the people were almost strangers and in real life conformity usually takes place when people are in groups with people they know well. Also, in 1950s America, people were more likely to conform as to be individual wasn't as widely accepted.

The study demonstrates the importance of compliance, with 3/4 outwardly conforming but inwardly disagreeing.

Ach's research involved follow up self reports which focused on factors such as feeling self-concious, having a fear of disapproval, and also anxiety. These suggest that normative social influence was at work. Self reports provide interesting information, however we cannot be sure that they accurately identify reasons why people conform. The fact that the participants were made to give their answer directly in front of the group will have maximised the normative social influence as they are more likely to be judged, or at least that is how they will have felt. This suggests it should be possible to reduce conformity by having the participants write down their judgements privately (-Asch found this in a follow up experiment and found conformity dropped to 12.5% amongst participants). This concludes that there is much less normative social influence when others aren't aware of your judgements - that makes sense!

A majority may be able to control other group members using this influence by making it difficult for them to deviate from the majority point of view, and thus pressuring them to conform. As humans, we have a fundamental need for social companionship and often have a fear of rejection though to what extent varies from person to person; these factors are why the normative social influence proves so substantial.

The extent of this influence has been investigated in terms of bullying: Garandeau and Cillessen (2006) showed how groups with a low quality of interpersonal friendships may be manipulated by a skilful bully so that victimisation of another child provides the group with a common goal. This creates pressure on all group members to comply.

It is important to note that Deutsch and Gerard argued that "commonly two types of influence are found together". Conformity doesn't have to be the result of just one or the other. 


Desutsch and Gerard (1955) successfully identified two key processes underlying conformity behaviour.

They discovered that you can reduce normative social influence by allowing people to make their judgements privately, allowing people to write down their judgements then throw them away, or by giving them social support.

They discovered you can increase informative social influence when a situation is ambiguous, when accuracy of the situation is crucial, when a supporter is likely to possess valid information (more likely to take it!), and when a person doubts their own ability.

Limitations to the theory:

1. It is designed to apply to the majority influence and only has some relevance to minority influence, and even the small relevance is unclear. However, evidence is mostly consistent with notion that minorities typically produce conformity through informative social influence rather than normative.

2. It is often not possible to decide whether the effects of any given factor on conformity behaviour are due to normative social influence, informational social influence or both. For example, you have a supporter which reduces conformity - the may be reducing normative social influence (in respect to the rest of the group) by being a social support, or it may actually be reducing the informative social influence by providing useful information.

3. Deutsch and Gerard (1955). They assumed that normative social influence would be extremely common because it occurs wherever individuals seek social approval and acceptance however there is more depth than that. I.e. studies have shown that conformity is higher when other group members are friends. Therefore group belongingness is more powerful that simply the need for social approval.

4. The extent of conformity depends on both the situation and personal characteristics. For example, individuals with less intelligence are often more affected by informational social influence, and individuals with a great need to be positively regarded by others and more affected by normative social influence. Most research in general, has focused on situational determinants of social influence so we lack a clear idea of how situation and personal factors interact to determine conformity behaviour.


Leah on November 10, 2012:

aways give references and/or bibliography

lovelyjubbly (author) on April 10, 2012:

Thank you very much. Yes, it's somewhat disturbing really, when you think about what it can lead to. But nether the less, interesting!

Catherine Simmons from Mission BC Canada on April 08, 2012:

Very interesting hub. I was caught by the fact that people actually start to disbelieve their own eyes and even though they think the other s are wrong they still conform!

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