New NBER Research

NBER Working Paper #20639     21 November 2014

Full-Day Service and Home Visits Raise Head Start's Impact

Head Start centers which offer full-day service boost cognitive skills more than other centers, and centers offering frequent home visiting are especially effective at raising non-cognitive skills, an analysis by Christopher Walters finds. Head Start also has its largest effects on children with less-educated mothers. Inputs such as teacher education and class size are not associated with increased effectiveness.

20 November 2014

Asymmetric Pass-Through of Tariffs

An examination by Douglas A. Irwin of the landed and the duty-inclusive prices of raw sugar in New York City from 1890 to 1930 reveals a striking asymmetry: Tariff decreases were immediately passed through to consumers with no impact on import prices, while 60 percent of tariff increases were absorbed by foreign exporters in the form of reduced import prices. The apparent explanation: Imports collapse in response to increases, but do not surge after reductions.

19 November 2014

Obesity and Gun Violence Offset Other Health Gains

Reduced smoking, safer driving and cars, and reduced heavy alcohol use led to health improvements estimated at 1.82 years of quality-adjusted life between 1960 and 2010, according to a study by Susan T. Stewart and David M. Cutler. However, these gains were roughly offset by increased obesity, and increased death rates from firearms and poisonous substances, which together reduced quality-adjusted life expectancy by 1.77 years.

18 November 2014

Do Tax Credits Affect R&D Expenditures by Small Firms? Evidence from Canada

Privately owned firms that became eligible for increased tax credits on a broader range of qualifying R&D expenditures increased R&D spending by an average of 15 percent, Ajay Agrawal, Carlos Rosell, and Timothy S. Simcoe discover in their analysis of 2004 changes in the Canadian Scientific Research and Experimental Development tax credit. They see evidence that small firms had lower responsiveness to the changes.
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