Ahmed Mushfiq Mobarak

The Impact of Urban Spatial Structure on Travel Demand in the United States

The authors combine measures of urban form and public transit supply for 114 urbanized areas with the 1990 Nationwide Personal Transportation Survey to address two questions: (1) How do measures of urban form, including city shape, road density, the spatial distribution of population, and jobs-housing balance affect the annual miles driven and commute mode choices of U.S. households? (2) How does the supply of public transportation (annual route miles supplied and availability of transit stops) affect miles driven and commute mode choice? The authors find that jobs-housing balance, population centrality, and rail miles supplied significantly reduce the probability of driving to work in cities with some rail transit. Population centrality and jobs-housing balance have a significant impact on annual household vehicle miles traveled (VMT), as do city shape, road density, and (in rail cities) annual rail route miles supplied. The elasticity of VMT with respect to each variable is small, on the order of 0.10-0.20 in absolute value. However, changing several measures of form simultaneously can reduce annual VMT significantly. Moving the sample households from a city with the characteristics of Atlanta to a city with the characteristics of Boston reduces annual VMT by 25 percent.

Democracy, Volatility, and Economic Development

Growth stability is an important objectivebecause development requires sustained increases in income, because volatility is costly for the poor, and because volatility deters growth. We study the determinants of average growth and its volatility as a two-equation system, and find that higher levels of democracy and diversification lower volatility, whereas volatility itself reduces growth. Muslim countries instrument for democracy, and measures of diversification identify volatility. In contrast to the lack of consensus on the democracygrowth relationship, the democracystability link is robust. Rather than focus on growth, this paper forges an alternative link between democracy and development through the volatility channel.

Low demand for nontraditional cookstove technologies

Biomass combustion with traditional cookstoves causes substantial environmental and health harm. Nontraditional cookstove technologies can be efficacious in reducing this adverse impact, but they are adopted and used at puzzlingly low rates. This study analyzes the determinants of low demand for nontraditional cookstoves in rural Bangladesh by using both stated preference (from a nationally representative survey of rural women) and revealed preference (assessed by conducting a cluster-randomized trial of cookstove prices) approaches. We find consistent evidence across both analyses suggesting that the women in rural Bangladesh do not perceive indoor air pollution as a significant health hazard, prioritize other basic developmental needs over nontraditional cookstoves, and overwhelmingly rely on a free traditional cookstove technology and are therefore not willing to pay much for a new nontraditional cookstove. Efforts to improve health and abate environmental harm by promoting nontraditional cookstoves may be more successful by designing and disseminating nontraditional cookstoves with features valued more highly by users, such as reduction of operating costs, even when those features are not directly related to the cookstoves’ health and environmental impacts.

Underinvestment in a profitable technology: : the case of seasonal migration in Bangladesh

Hunger during pre-harvest lean seasons is widespread in the agrarian areas of Asia and Sub-Saharan Africa. We randomly assign an

Selling formal Insurance to the Informally Insured

8.50 incentive to households in rural Bangladesh to temporarily out-migrate during the lean season. The incentive induces 22% of households to send a seasonal migrant, their consumption at the origin increases significantly, and treated households are 8–10 percentage points more likely to re-migrate 1 and 3 years after the incentive is removed. These facts can be explained qualitatively by a model in which migration is risky, mitigating risk requires individual-specific learning, and some migrants are sufficiently close to subsistence that failed migration is very costly. We document evidence consistent with this model using heterogeneity analysis and additional experimental variation, but calibrations with forward-looking households that can save up to migrate suggest that it is difficult for the model to quantitatively match the data. We conclude with extensions to the model that could provide a better quantitative accounting of the behavior.

Skilled Immigration and Innovation: Evidence from Enrollment Fluctuations in U.S. Doctoral Programs

Unpredictable rainfall is an important risk for agricultural activity, and farmers in developing countries often receive incomplete insurance from informal risk-sharing networks. We study the demand for, and effects of, offering formal index-based rainfall insurance through a randomized experiment in an environment where the informal risk sharing network can be readily identified and richly characterized: sub-castes in rural India. A model allowing for both idiosyncratic and aggregate risk shows that informal networks lower the demand for formal insurance only if the network indemnifies against aggregate risk, but not if its primary role is to insure against farmer-specific losses. When formal insurance carries basis risk (mismatches between payouts and actual losses due to the remote location of the rainfall gauge), informal risk sharing that covers idiosyncratic losses enhance the benefits of index insurance. Formal index insurance enables households to take more risk even in the presence of informal insurance. We find substantial empirical support of these nuanced predictions of the model by conducting the experiment (randomizing both index insurance offers, and the locations of rainfall gauges) on castes for whom we have a rich history of group responsiveness to household and aggregate rainfall shocks.

The Transforming Power of Democracy: Regime Type and the Distribution of Electricity

We study the contribution of foreign science and engineering talent to the creation of new knowledge in the U.S. economy using panel data on 2300 science and engineering (S&E) departments at 100 large American universities from 1973 to 1998. We use macroeconomic shocks and policy changes in source countries that differentially affect enrollments across fields and universities to isolate exogenous variation in the supply of students at specific departments. Both foreign and domestic graduate students are central inputs into knowledge creation, and the marginal foreign student contributes more to the production of scientific publications and citations. A 10% decrease in the foreign share of doctoral students lowers S&E research output at U.S. universities by 5-6%. A theoretical model of university admissions and scholarships helps us infer the productivity effects of student quality, and econometric results indicate that any visa restrictions limiting entry of high-quality foreign students is most costly for U.S. innovation. Increased diversity appears to be the primary mechanism by which foreign students improve research outcomes. The impact of more restrictive immigration policies depends on how they affect the quality margin and diversity of incoming foreigners.

Encouraging sanitation investment in the developing world: A cluster-randomized trial

Theory on democracy and its consequences turns on how democracy influences behavior among politicians and the citizenry. Ultimately, the literature seeks to determine who benefits under democratic rules. This is our concern, posed in a context that allows us to address a classic question: does democracy favor large but diffuse segments of society over small but concentrated interests? We employ sectoral electricity consumption data for a panel of 733 country-years to examine democracys impact on the distribution of electricity across three sectors that represent distinct political interests: industry, agriculture, and residential consumers. We find that in poorer countries democratization produces significant increases in the residential share of electricity relative to industry, suggesting sectors with less per capita financial clout, but a stronger voice in elections benefit under democracy. Unlike the large literatures on democracys impact on the amounts of publicly provided goods, our results are among the first on the distribution of those goods.

The Political Economy of Health Services Provision and Access in Brazil

Helping the poor invest in sanitation Almost a third of the worlds people do not have access to hygienic latrines. Improving access to and increasing the use of latrines would reduce deaths and poor health caused by diarrheal disease. Guiteras et al. tested the relative benefits of supplying health information, offering a financial subsidy to purchasers of hygienic latrines, or increasing the availability of latrines for purchase. Providing the subsidy worked best: Nonsubsidized households were more likely to purchase latrines when other households in their village were subsidized. Science, this issue p. 903 Giving a financial boost to the poorest households improves access to sanitation for all villagers. Poor sanitation contributes to morbidity and mortality in the developing world, but there is disagreement on what policies can increase sanitation coverage. To measure the effects of alternative policies on investment in hygienic latrines, we assigned 380 communities in rural Bangladesh to different marketing treatments—community motivation and information; subsidies; a supply-side market access intervention; and a control—in a cluster-randomized trial. Community motivation alone did not increase hygienic latrine ownership (+1.6 percentage points, P = 0.43), nor did the supply-side intervention (+0.3 percentage points, P = 0.90). Subsidies to the majority of the landless poor increased ownership among subsidized households (+22.0 percentage points, P < 0.001) and their unsubsidized neighbors (+8.5 percentage points, P = 0.001), which suggests that investment decisions are interlinked across neighbors. Subsidies also reduced open defecation by 14 percentage points (P < 0.001).

Gender Differences in the Effects of Vocational Training: Constraints on Women and Drop-Out Behavior

The authors examine the impact of local politics and government structure on the allocation of publicly subsidized (SUS) health services across municipios (counties) in Brazil, and on the probability that uninsured individuals who require medical attention actually receive access to those health services. Using data from the 1998 PNAD survey they demonstrate that higher per capita levels of SUS doctors, nurses, and clinic rooms increase the probability that an uninsured individual gains access to health services when he, or she seeks it. The authors find that an increase in income inequality, an increase in the percentage of the population that votes, and an increase in the percentage of votes going to left-leaning candidates are each associated with higher levels of public health services. The per capita provision of doctors, nurses, and clinics is also greater in counties with a popular local leader, and in counties where the county mayor and state governor are politically aligned. Administrative decentralization of health services to the county decreases provision levels, and reduces access to services by the uninsured, unless it is accompanied by good local governance.