Many believed that rise in opioid use was driven by demand for painkillers

There are sizable, long-term returns to investments in means-tested, public preschool programs: Head Start (comprehensive education services to children of low-income families) has generated large boosts in in high school completion, college enrollment and college completion among affected students.

Growth by proximity – Moretti on the effect of high-tech hubs on innovation

In 2005, Texas sharply reduced the provision of special education (education services that accommodate individuals with disabilities and special needs)

Southern slaveholder households in 1860 lost substantially more wealth by 1870 than comparable Southern households

Medicaid coverage for children has more than paid for itself in the long run

Criminal registration in DNA databases massively reduces the likelihood that criminals re-offend, and increases the probability that offenders are identified if they do re-offend

Father Couglin's radio broadcasts (which blended populist demagoguery, anti-Semitism, and fascist sympathies) reduced Franklin D

"Early childhood Medicaid eligibility reduces mortality and disability, increases employment, and reduces receipt of disability transfer programs up to 50 years later

Researchers found that extending the length of unemployment insurance had no significant impact on employment