These analyses evaluated the extent to which one’s own alcohol consumption (SELF) and the perceived drinking behavior of one’s peers (PEER) are phenotypically related due to theoretically causal relationships (social selection and social influence) versus shared genetic and/or environmental liabilities. The current findings indicate that both shared liability and causal factors are relevant. Most covariation is attributable to shared liability, and only non-shared environmental influences acted via causal pathways.
