NSI and ISI

Conformity is when you change your behaviour to do something more similar to what others are doing.  It can be divided into two types (Deutsch & Gerard, 1955):

• Normative social influence - going along with others in order to fit in
• Informational social influence - going along with others because we don't know what to do

This depends on whether you have a clear idea of how to act in a situation.  If you know how to act but choose to do what others are doing instead, then it is an example of normative social influence.  It is so called because you are going along with a social norm, rather than your own choice.

Situations where you don't have a clue what to do - such as how to use the public transport system in a foreign country - and choose to copy others, are examples of informational social influence - so called, because you look to others for information.

Research into NSI and ISI

The most famous research study in this area of Psychology is the 'length of lines' study by Asch (1955).  Given a simple task of comparing the length of lines, Asch's participants gave the wrong answer because they didn't want stand out from the group.  This is an example of NSI.  A key question to ask is whether they knew the right answer, and what they would have done when alone.

Jenness (1932)'s study of estimates of the number of beans in a jar is a great example of ISI.  Here, people didn't know the right answer.  They wanted to give the right answer, so they were influence by the guesses of other people.

Conformity is more prevalent than many people might think (or admit to themselves), and the reason it doesn't get more attention is that it is usually not a problem. In fact, it can be very helpful. If people all stand on the same side of an escalator, it helps others to walk past.  People are, rightly, concerned when conformity leads to crimes or substance abuse, but the basic underlying processes of NSI and ISI happen to us all on a daily basis.

-> Read how this applies to characters in fiction.

References
Asch, S.E. (1955). Opinions and social pressure. Scientific American, 193, 31-35.
Deutsch, M., and Gerard, H.B. (1955).  A study of normative and informational social influences upon individual judgment.  Journal of Abnormal and Social Psychology, 51(3), 629-636.
Jenness, A. (1932). The role of discussion in changing opinion regarding matter of fact. Journal of Abnormal and Social Psychology, 27, 279-296.