I consider the alcohol consumption of opposite-gender peers as explanatory to adolescent sexual intercourse and demonstrate that female sexual activity is higher where there is higher alcohol consumption among male peers. This relationship is robust to school fixed effects, cannot be explained...

The 'friendship paradox' (Feld1991) refers to the fact that, on average, people have strictly fewer friends than their friends have. I show that this over-sampling of the most popular people amplifies behaviors that involve complementarities. People with more friends experience greater...

This paper investigates the relationship between personality traits in adolescence and health behaviours using a large and recent cohort study. In particular, we investigate the impact of locus of control, self-esteem and conscientiousness at age 15-16, on the incidence of health behaviours such...

Most work on social interactions studies a single, composite effect of interactions within a group. Yet in the case of sexual initiation, there are two distinct social mechanisms-peer-group norms and partner availability-with separate effects and different potential interventions. Here I develop...

I consider the alcohol consumption of opposite-gender peers as explanatory to adolescent sexual intercourse and demonstrate that female sexual activity is higher where there is higher alcohol consumption among male peers. This relationship is robust to school fixed effects, cannot be explained...

This paper examines peer effects in adolescent cannabis use from several different reference groups, exploiting survey data that have many desirable properties and have not previously been used for this purpose. Treating the school grade as the reference group, and using both neighbourhood fixed...