"Tell me who you hang out with": classroom peer effects on psychoactive substances consumption

Abstract

I use Colombian data to estimate peer effects for psychoactive substance consumption among high school students and identify channels for these effects. Instrumenting classroom consumption with that of the household yields that an increase of 10% in the proportion of classroom users of alcohol, cannabis, and cocaine increases the probability of students to use each substance in 3.14%, 4.29%, and 2.38% respectively. Data provides channels of these effects, specifically that the effect is explained by students who interact with consumers, leading to easier access to drugs or a decrease in the perceived risk of consuming these substances.