Knowledge that Transforms

We study the impact of large exchange rate devaluations on the cost of living at different points on the income distribution. Poor households spend relatively more on tradeable product categories and consume lower-priced varieties within categories. Changes in the relative price of tradeables and of lower-priced varieties affect the cost of living of low-income relative to high-income households. We quantify these effects following the 1994 Mexican devaluation and show that they can have large distributional consequences. Two years post-devaluation, the cost of living for the bottom income decile rose 1.48 to 1.62 times more than for the top income decile. (JEL D12, D31, E31, F31, O12, O19, O24)

Two identical firms who start exporting in different months, one each in January and December, will report dramatically different exports for the first calendar year. This partial-year effect biases down first-year export levels and biases up first-year export growth rates. For Peruvian exporters, the partial-year bias is large: first-year export levels are understated by 54 percent and the first-year growth rate is overstated by 112 percentage points. Correcting the partial-year effect dramatically reduces first-year export growth rates, raises initial export levels, and almost doubles the contribution of net firm entry and exit to overall export growth. (JEL D22, F14)

We study how relational contracts mitigate Becker's classic problem of providing general human capital when training contracts are incomplete. The firm's profit-maximizing agreement is a multiperiod apprenticeship in which the novice is trained gradually over time and eventually receives all knowledge. The firm adopts a 1/e rule, whereby at the beginning of the relationship the novice is trained, for free, just enough to produce a fraction 1/e of the efficient output. After that, the novice earns all additional knowledge with labor. This rule causes inefficiently lengthy relationships that grow longer the more patient the players. A minimum wage is welfare enhancing. (JEL D82, D86, J24, M53)

We show that a number of noncognitive skills and preferences, including patience and identity, are malleable in adults, and that investments in them reduce crime and violence. We recruited criminally engaged men and randomized one-half to eight weeks of cognitive behavioral therapy designed to foster self-regulation, patience, and a noncriminal identity and lifestyle. We also randomized $200 grants. Cash alone and therapy alone initially reduced crime and violence, but effects dissipated over time. When cash followed therapy, crime and violence decreased dramatically for at least a year. We hypothesize that cash reinforced therapy's impacts by prolonging learning-by-doing, lifestyle changes, and self-investment.

We examine the impact of policy uncertainty on trade, prices, and real income through firm entry investments in general equilibrium. We estimate and quantify the impact of trade policy on China's export boom to the United States following its 2001 WTO accession. We find the accession reduced the US threat of a trade war, which can account for over one-third of that export growth in the period 2000– 2005. Reduced policy uncertainty lowered US prices and increased its consumers' income by the equivalent of a 13-percentage-point permanent tariff decrease. These findings provide evidence of large effects of policy uncertainty on economic activity and the importance of agreements for reducing it. (JEL D72, F13, F14, O19, P33)

The 1870–1913 period marked the birth of the first era of trade globalization. How did this tremendous increase in trade affect economic development? This work isolates a causality channel by exploiting the fact that the introduction of the steamship in the shipping industry produced an asymmetric change in trade distances among countries. Before this invention, trade routes depended on wind patterns. The steamship reduced shipping costs and time in a disproportionate manner across countries and trade routes. Using this source of variation and novel data on shipping, trade, and development, I find that (i) the adoption of the steamship had a major impact on patterns of trade worldwide; (ii) only a small number of countries, characterized by more inclusive institutions, benefited from trade integration; and (iii) globalization was the major driver of the economic divergence between the rich and the poor portions of the world in the years 1850–1900. (JEL F14, F43, F63, L92, N70, O33)

We propose a novel and easy-to-implement approach to detect potential overbilling based on the hours worked implied by the service codes which physicians submit to Medicare. Using the Medicare Part B Fee- for-Service (FFS) Physician Utilization and Payment Data in 2012 and 2013 released by the Centers for Medicare and Medicaid Services, we construct estimates for physicians' hours spent on Medicare beneficiaries. We find that about 2,300 physicians, representing about 3 percent of those with 20 or more hours of Medicare Part B FFS services, have billed Medicare over 100 hours per week. We consider these implausibly long hours.

Coordinated single-offer school assignment systems are a popular education reform. We show that uncoordinated offers in NYC's school assignment mechanism generated mismatches. One-third of applicants were unassigned after the main round and later administratively placed at less desirable schools. We evaluate the effects of the new coordinated mechanism based on deferred acceptance using estimated student preferences. The new mechanism achieves 80 percent of the possible gains from a no-choice neighborhood extreme to a utilitarian benchmark. Coordinating offers dominates the effects of further algorithm modifications. Students most likely to be previously administratively assigned experienced the largest gains in welfare and subsequent achievement. (JEL C78, D82, I21, I28)

This paper models the optimal search strategies of the unemployed across space to characterize local labor markets. Our methodology allows for linkages between numerous areas, while preserving tractability. We estimate that labor markets are quite local, as the attractiveness of jobs to applicants sharply decays with distance. Also, workers are discouraged from searching in areas with strong competition from other job-seekers. However, as labor markets overlap, a local stimulus or transport improvements have modest effects on local outcomes, because ripple effects in job applications dilute their impact across a series of overlapping markets. (JEL J61, J64, R23, R58)

An ongoing debate in employment policy is whether promoting small and medium enterprises creates jobs. We use the elimination of small-scale industry (SSI) promotion in India to address this question. For 60 years, SSI promotion in India focused on reserving certain products for manufacture by small and medium enterprises. We identify the consequences for employment growth, investment, output, productivity, and wages of dismantling India's SSI reservations. We exploit variation in the timing of de-reservation across products and also measure the long-run impact of national SSI policy changes using variation in pretreatment exposure at the district level. Districts more exposed to de-reservation experienced higher employment and output growth. Entrants into the de-reserved product spaces and incumbents that were previously constrained by the size restrictions drove the increase in growth. The results suggest that dismantling India's SSI policies encouraged overall employment growth. (JEL E24, L25, L53, L60, O14, O25)