The Pygmalion Effect

The Pygmalion effect is where higher expectations lead to higher performance.

Our beliefs about another person's abilities affect our actions towards that person. The action impacts the other's beliefs about themselves and causes the action of the other person toward us, which further reinforce our beliefs about that person.

The Pygmalion effect is also known as the Rosenthal experiment, named after research of Robert Rosenthal at Harvard.

In a test, Rosenthal challenged test subjects to coach rats through a maze. Half were told that the rats were very intelligent,  the other half were told that their rats were dumb. The rats were all the same.

During an experiment, the "clever" rats outperformed the "dumb" rats. 

Rosenthal did the Pygmalion study in a school.

At the start of the school year, a group of elementary school teachers were told that their new pupils were very talented, while they were really random average students. 

By the end of the year, the students that were described as more talented had significantly increased their performance compared to the rest of the class.

Rosenthal concluded that when "we expect certain behaviours of others we are likely to act in ways that make the expected behaviour more likely to occur."