Using data from two cohorts of students, we present evidence that children who are relatively old when they enter kindergarten score higher on achievement tests and are less likely to repeat grades or suffer from learning disabilities than their younger classmates. These differences are driven...

"The NBER Bulletin on Aging and Health provides summaries of publications like this. You can sign up to receive the NBER Bulletin on Aging and Health by email. A number of studies have found substantial correlations in risky behavior between siblings, raising the possibility that adolescents may...

The large sibling correlations in risky behaviour between siblings raise the possibility that adolescents may directly influence the actions of their brothers or sisters. We assess the extent to which correlations in substance use and selling drugs are causal. Our identification strategy relies...