What are Social Norms and Why They Matter?
Social norms can be a major artery to effective influence. Prescriptive social norms define what an acceptable behavior is in a particular society or a social group, for example, that it is not okay to have your cell phone ringing when you’re in a church and your pastor is reaching a climax in his speech.
People conform to social norms in order to accepted, to avoid embarrassment, to be liked. The more people care about other people’s acceptance, the greater is the power of social norms. Social norms are especially useful when trying to change people’s behavior based on pluralistic ignorance, a phenomenon as widespread as malaria and traffic accidents combined, but which lacks popular recognition commensurate with its pervasiveness.
What is Pluralistic Ignorance?
Pluralistic ignorance happens when people mistakenly think that some social norm is widely accepted by everyone else and they therefore act accordingly, even though in all conscience only few people think that such behavior is appropriate. 
For instance, you might have no problem with gays or bisexuals, but you think that all your close friends —Jack, Jill, Billy, and Betty—disdain the people wrapped in the rainbow flag, so you err on the side of expressing homophobic attitudes. Jack likewise has no problems with gays, but he thinks that you, Jill, Billy, and Betty dislike gays. And it goes on with the other people in your group. So each of you deep inside might be very tolerant of homosexuals, but you all mistakenly assume that everyone else dislikes LGBT people and all end up showing your dislike. This is not a hypothetical example, as studies show that for example most college students overestimate homophobic tendencies among their peers, so everyone ends up showing less tolerance towards LGBT students because they misread the actual social norm. 
Using Social Norms to Cure Pluralistic Ignorance
Pluralistic ignorance can be cured by revealing the actual, correct social norm. One example of how social norms can help change behavior is binge drinking on college campuses. Most college students don’t approve of binge drinking, but everyone thinks that everyone else approves of it. So most students misread the true social norm, and this leads to more binge drinking than is in fact acceptable to everyone.  Research shows, accordingly, that an effective way to reduce binge drinking is to inform college students that most of their peers don’t binge drink and that they don’t think it is socially acceptable.
- Dale T. Miller and Cathy McFarland, Pluralistic Ignorance: When Similarity is Interpreted as Dissimilarity, Journal of Personality and Social Psychology, 53, 298-305 (1987).
- Anne M. Bowen, and Martin J. Bourgeois, Attitudes Toward Lesbian, Gay, And Bisexual College Students: The Contribution of Pluralistic Ignorance, Dynamic Social Impact, And Contact Theories, Journal of American College Health, 50, 91-96 (2001).
- Deborah A. Prentice and Dale T. Miller, Pluralistic Ignorance and Alcohol Use on Campus: Some Consequences of Misperceiving the Social Norm, Journal of Personality and Social Psychology, 64, 243-256 (1993); H. Wesley Perkins, Philip W. Meilman, Jami S. Leichliter, Jeffrey R. Cashin, and Cheryl A. Presley, Misperceptions of the Norms for the Frequency of Alcohol and Other Drug Use on College Campuses, Journal of American College Health, 47, 253-258 (1999).