This is the 2007 version. Click here for the 2017 chapter 15 table of contents.

Sherif (1936): Group Norms and Conformity

Muzafer Sherif conducted a classic study on conformity in 1936. Sherif put subjects in a dark room and told them to watch a pinpoint of light and report how far it moved. Psychologists had previously discovered that a small, unmoving light in a dark room often appeared to be moving. This was labeled the autokinetic effect. The autokinetic effect is an illusion because the light does not actually move. However, people almost always believe that it does.

Why did Sherif study the autokinetic effect?

Realizing that an experience that is completely "in people's heads" might be readily influenced by suggestion, Sherif decided to study how people were influenced by other people's opinions, in their perception of the autokinetic effect.

First Sherif studied how subjects reacted to the autokinetic effect when they were in a room by themselves. He found that they soon established their own individual norms for the judgment—usually 2 to 6 inches. In other words, when given many opportunities (trials) to judge the movement of the light, they settled on a distance of 2-6 inches and became consistent in making this judgment from trial to trial.

What happened when people judged the autokinetic effect by themselves?

What happened when people were put into groups?

In the next phase of the experiment, groups of subjects were put in the dark room, 2 or 3 at a time, and asked to agree on a judgment. Now Sherif noted a tendency to compromise. People who usually made an estimate like 6 inches soon made smaller judgments like 4 inches. Those who saw less movement, such as 2 inches, soon increased their judgments to about 4 inches. People changed to more resemble the others in the group.

Sherif's subjects were not aware of this social influence. When Sherif asked subjects directly, "Were you influenced by the judgments of other persons during the experiments," most denied it. However, when subjects were tested one at a time, later, most now conformed to the group judgment they recently made. A subject who previously settled on an estimate of 2 inches or 6 inches was more likely (after the group experience) to say the light was moving about 4 inches. These subjects had been changed by the group experience, whether they realized it or not. They had increased their conformity to group norms.

Group norms are agreed-upon standards of behavior. Sherif's experiment showed group norms are established through interaction of individuals and the leveling-off of extreme opinions. The result is a consensus agreement that tends to be a compromise...even if it is wrong.

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