Sex ratios, i.e., relative numbers of men and women, can affect marriage prospects, labor force participation, and other social and economic variables. But the observed association between sex ratios and social and economic conditions may be confounded by omitted variables and reverse causality....

We propose the rise of crack cocaine markets as an explanation for the end to the convergence in black-white educational outcomes beginning in the mid-1980s. After constructing a measure to date the arrival of crack markets in cities and states, we show large increases in murder and...

Federal and state laws passed in the late 1990 increased considerably postpartum stays for newborns. Using all births in California over the 1995-2001 period, 2SLS estimates suggest that for the average newborn impacted by the law, increased treatment intensity had modest and statistically...

We attribute the recent quadrupling of heroin death rates to the August, 2010 reformulation of an oft-abused prescription opioid, OxyContin. The new abuse-deterrent formulation led many consumers to substitute to an inexpensive alternative, heroin. Using structural break techniques and variation...