Social Multipliers in Sexual Initiation Decisions among U.S. High School Students

Jason Fletcher, University of Wisconsin at Madison

This paper uses a national sample of high school students to test for several types of social influences on the decision to have sexual intercourse. I find evidence of endogenous social interactions (social multipliers), where the propensity of an individual choosing to have sex varies with the average behavior in his school. Additionally, the magnitude of the social multipliers and several other interesting risk factors differ by gender and race. These finding might help explain the large variation in sexual initiation across schools in the United States. Additionally these results add to the debate over school vouchers and ability grouping. Large multipliers imply large changes in school-wide rates of sexual behavior with moderate changes in school-body composition. In this way, school vouchers and ability grouping might exacerbate the situation of high teenage pregnancy rates and out-of-wedlock births in some communities.