Some Examples of Social Proof.
1. Advertisers often tell us that their product is the "largest selling" car, album, etc.
2. Craig and Prkachin (1978) administered shock to a subject. They asked the person how painful the shocks were and obtained physiological measures of pain. People felt less shock (on both the verbal and physiological indices) if they were in the presence of another subject who was apparently experiencing little or no pain.
3. A well-known evangelist (Altheide & Johnson, 1977) plants workers in the audience. These people come to the alter at varying intervals to create the impression of a spontaneous mass outpouring.
4. Milgram, Bickman, and Berkowitz (1969) conducted a social contagion study on 42nd Street, New York City. Varying numbers of passersby (all confederates) were staring at a sixth floor window. The dependent variable was the percentage of persons who stopped to stare. As the number of sources increased, the percentage of persons who stopped to stare also increased. Forty-five percent of passersby stopped if one confederate was looking up, 85% of the passersby stopped if 15 confederates were looking up.
5. Bartenders sometimes "salt" the tip jar to simulate generosity on the part of patrons.
6. Bandura, Grusec, and Menlove (1967) used the principle
of social proof to treat young children who were terrified of dogs. The
treatment was very simple. They merely watched a boy play happily with
a dog for twenty minutes a day. After only four days, 67 percent of the
clients climbed in a playpen with a dog and played with him.