New NBER Research

5 March 2015

Migration, Congestion Externalities, and the Evaluation of Spatial Investments

Using the example of rural household electrification in South Africa, Taryn Dinkelman and Sam Schulhofer-Wohl demonstrate the importance of accounting for migration when evaluating welfare gains of public programs with spatially-targeted benefits. Building new infrastructure can induce in-migration to an area, creating congestion and potentially offsetting the infrastructure’s direct benefits. Their estimates suggest that congestion externalities from program-induced migration reduced local welfare gains by about 40 percent.

4 March 2015

Does Delay Cause Decay?

David H. Autor, Nicole Maestas, Kathleen J. Mullen, and Alexander Strand find that time out of the labor force affects subsequent employment of Social Security Disability Insurance (SSDI) applicants. A one standard deviation (2.1 month) increase in initial processing time for a disability insurance application reduces long-run “substantial gainful activity” rates by 0.36 percentage points (3.5%) and long-run annual earnings by $178 (5.1%).

3 March 2015

The Returns to the Federal Tax Credits for Higher Education

The size and availability of federal tax credits benefiting households that pay tuition and fees for higher education have expanded enormously in the years beginning in 2009. Their 2011 revenue cost was $25 billion. George B. Bulman and Caroline M. Hoxby examine a number of potential outcome measures and find that despite their cost, these credits appear to have negligible causal effects.
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March NBER Digest
An Analysis of Asian Growth Prospects

NBER researchers write that typical degrees of regression to the mean imply substantial slowdowns in the Chinese and Indian economies. Articles in the latest NBER Digest also examine the value of educational credentials in the labor market, the effectiveness of microlending, the impact of U.S. mortgage rate reductions, the dynamics of tariff changes, and results of capital controls in Brazil.

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Foreign-Exchange Operations and
Monetary Policy in the 20th Century

 Drawing on a trove of previously confidential data, "Strained Relations," a new NBER book from The University of Chicago Press, reveals the evolution of U.S. policy regarding currency-market intervention and its interaction with monetary policy. The authors consider how foreign-exchange intervention was affected by changes such as the abandonment of the international gold standard as well as by political and bureaucratic factors.

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