Publications by Type: Working Paper

Khwaja, Asim Ijaz, Tahir Andrabi, and Jishnu Das. 2014. “

Report Cards: The Impact Of Providing School And Child Test Scores On Educational Markets

We study the impact of providing school and child test scores on subsequent test scores, prices, and enrollment in markets with multiple public and private providers. A randomly selected half of our sample villages (markets) received report cards. This increased test scores by 0.11 standard deviations, decreased private school fees by 17 percent and increased primary enrollment by 4.5 percent. Heterogeneity in the treatment impact by initial school quality is consistent with canonical models of asymmetric information. Information provision facilitates better comparisons across providers, improves market efficiency and raises child welfare through higher test scores, higher enrollment and lower fees.
Iyer, Rajkamal, Asim Ijaz Khwaja, Erzo FP Luttmer, and Kelly Shue. 2014. “

Screening Peers Softly: Inferring The Quality Of Small Borrowers

This paper examines the performance of new online lending markets that rely on non-expert individuals to screen their peers’ creditworthiness. We find that these peer lenders predict an individual’s likelihood of defaulting on a loan with 45% greater accuracy than the borrower’s exact credit score (unobserved by the lenders). Moreover, peer lenders achieve 87% of the predictive power of an econometrician who observes all standard financial information about borrowers. Screening through soft or nonstandard information is relatively more important when evaluating lower quality borrowers. Our results highlight how aggregating over the views of peers and leveraging nonstandard information can enhance lending efficiency
Hanna, Rema, and Shing-yi Wang. 2013. “

Dishonesty And Selection Into Public Service

In this paper, we demonstrate that university students who cheat on a simple task in a laboratory setting are more likely to state a preference for entering public service. Importantly, we also show that cheating on this task is predictive of corrupt behavior by real government workers, implying that this measure captures a meaningful propensity towards corruption. Students who demonstrate lower levels of prosocial preferences in the laboratory games are also more likely to prefer to enter the government, while outcomes on explicit, two-player games to measure cheating and attitudinal measures of corruption do not systematically predict job preferences. We find that a screening process that chooses the highest ability applicants would not alter the average propensity for corruption among the applicant pool. Our findings imply that differential selection into government may contribute, in part, to corruption. They also emphasize that screening characteristics other than ability may be useful in reducing corruption, but caution that more explicit measures may offer little predictive power.
Hanna, Rema, Vivi Alatas, Abhijit Banerjee, Benjamin A Olken, Ririn Purnamasari, and Matthew Wai-Poi. 2013. “

Ordeal Mechanism In Targeting: Theory And Evidence From A Field Experiment In Indonesia

This paper explores whether ordeal mechanisms can improve the targeting of aid programs to the poor ("self-targeting"). We first show that theoretically the impact of increasing ordeals is ambiguous: for example, time spent applying imposes a higher monetary cost on the rich, but may impose a higher utility cost on the poor. We examine these issues by conducting a 400-village field experiment with Indonesia’s Conditional Cash Transfer program (PKH), where eligibility is determined through an asset test. Specifically, we compare targeting outcomes from self-targeting, where villagers came to a central site to apply and take the asset test, against the status quo, an automatic enrollment system among a pool of potential candidates that the village pre-identified. Within self-targeting villages, we find that the poor are more likely to apply, even conditional on whether they would pass the asset test. Exploiting the experimental variation, we find that self-targeting leads to a much poorer group of beneficiaries than the status quo. Selftargeting also outperforms a universal asset-based automatic enrollment system that we construct using our survey data. However, while experimentally increasing the distance to the application site reduces the number of applicants, it does not differentially improve targeting. Estimating our model structurally, we show that there are large unobserved shocks in the decision to apply, and therefore increasing waiting times to 9 hours or more would be required to induce detectable additional selection. In short, ordeal mechanisms can induce self-selection, but marginally increasing the ordeal can impose additional costs on applicants without necessarily improving targeting.
Hanna, Rema, Vivi Alatas, Abhijit Banerjee, Benjamin A Olken, Ririn Purnamasari, and Matthew Wai-Poi. 2013. “

Does Elite Capture Matter? Local Elites And Targeted Welfare Programs In Indonesia

This paper investigates the impact of elite capture on the allocation of targeted government welfare programs in Indonesia, using both a high-stakes field experiment that varied the extent of elite influence and non-experimental data on a variety of existing government transfer programs. Conditional on their consumption level, there is little evidence that village elites and their relatives are more likely to receive aid programs than non-elites. Looking more closely, however, we find that this overall result masks a difference between different types of elites: those holding formal leadership positions are more likely to receive benefits, while informal leaders are actually less likely to. We show that capture by formal elites occurs during the distribution of benefits under the programs, and not during the processes when the beneficiary lists are determined by the central government. However, while elite capture exists, the welfare losses it creates appear quite small: since formal elites and their relatives are only 9 percent richer than non-elites, are at most about 8 percentage points more likely to receive benefits than non-elites, and represent at most 15 percent of the population, eliminating elite capture entirely would improve the welfare gains from these programs by less than one percent.
Hanna, Rema, Eva Arceo, and Paulina Oliva. 2012. “

The Effect Of Pollution On Labor Supply: Evidence From A Natural Experiment In Mexico

Much of what we know about the marginal effect of pollution on infant mortality is derived from developed country data. However, given the lower levels of air pollution in developed countries, these estimates may not be externally valid to the developing country context if there is a nonlinear dose relationship between pollution and mortality or if the costs of avoidance behavior differs considerably between the two contexts. In this paper, we estimate the relationship between pollution and infant mortality using data from Mexico. We find that an increase of 1 parts per billion in carbon monoxide (CO) over the last week results in 0.0032 deaths per 100,000 births, while a 1 μg/m3 increase in particulate matter (PM10) results in 0.24 infant deaths per 100,000 births. Our estimates for PM10 tend to be similar (or even smaller) than the U.S. estimates, while our findings on CO tend to be larger than those derived from the U.S. context. We provide suggestive evidence that a non-linearity in the relationship between CO and health explains this difference.
Bjorkman-Nyqvist, Martina, Jakob Svensson, and David Yanagizawa-Drott. 2012. “

The Market For (Fake) Antimalarial Medicine: Evidence From Uganda

Counterfeit and sub-standard antimalarial drugs present a growing threat to public health. This paper investigates the mechanisms that determine the prevalence of fake antimalarial drugs in local markets, their effects, and potential interventions to combat the problem. We collect drug samples from a large set of local markets in Uganda using covert shoppers and employ Raman spectroscopy to test for drug quality. We find that 37 percent of the local outlets sell fake antimalarial drugs. Motivated by a simple model, we conduct a market-level experiment to test whether authentic drugs can drive out fake drugs from the local market. We find evidence of such externalities: the intervention reduced prevalence of substandard and counterfeit drugs in incumbent outlets by half. We also provide suggestive evidence that misconceptions about malaria lead consumers to overestimate antimalarial drug quality, and that opportunistic drug shops exploit these misconceptions by selling substandard and counterfeit drugs. Together, our results indicate that high quality products can drive out low quality ones, but the opposite is true when consumers are less able to infer product quality.
Yanagizawa-Drott, David. 2012. “

Propaganda And Conflict: Theory And Evidence From The Rwandan Genocide

This paper investigates the role of mass media in times of conflict and state-sponsored violence. A model of collective violence is presented where mass media has the potential to increase participation in conflict by facilitating coordination, in addition to any direct effect on behavior due to content. Guided by the insights of the model, the paper uses a unique nation-wide village-level dataset from the Rwandan Genocide to estimate the impact of radio broadcasts that called for the extermination of the Tutsi minority, and are commonly believed to have played a signi…ficant role in fueling the violence. The results show that the broadcasts increased participation in the killings. They indicate that approximately 10 percent, or an estimated 51,000 perpetrators, of the participation in the violence during the Rwandan Genocide can be attributed to the effects of the radio. Violence that inherently requires more coordination, such as militia and army violence, was also more affected by the broadcasts. Together with a set of results presented in the paper, the evidence indicates that mass media can in part affect conflict by functioning as a coordination device.
Hanna, Rema, Vivi Alatas, Abhijit Banerjee, Arun G Chandrasekhar, and Benjamin A Olken. 2012. “

Network Structure And The Aggregation Of Information: Theory And Evidence From Indonesia

We use a unique data-set from Indonesia on what individuals know about the income distribution in their village to test theories such as Jackson and Rogers (2007) that link information aggregation in networks to the structure of the network. The observed patterns are consistent with a basic diffusion model: more central individuals are better informed and individuals are able to better evaluate the poverty status of those to whom they are more socially proximate. To understand what the theory predicts for cross-village patterns, we estimate a simple diffusion model using within-village variation, simulate network-level diffusion under this model for the over 600 different networks in our data, and use this simulated data to gauge what the simple diffusion model predicts for the cross-village relationship between information diffusion and network characteristics (e.g. clustering, density). The coefficients in these simulated regressions are generally consistent with relationships suggested in previous theoretical work, even though in our setting formal analytical predictions have not been derived. We then show that the qualitative predictions from the simulated model largely match the actual data in the sense that we obtain similar results both when the dependent variable is an empirical measure of the accuracy of a village’s aggregate information and when it is the simulation outcome. Finally, we consider a real-world application to community based targeting, where villagers chose which households should receive an anti-poverty program, and show that networks with better diffusive properties (as predicted by our model) differentially benefit from community based targeting policies.
Hanna, Rema, Esther Duflo, and Michael Greenstone. 2012. “

Up In Smoke: The Influence Of Household Behavior On The Long-Run Impact Of Improved Cooking Stoves

It is conventional wisdom that it is possible to reduce exposure to indoor air pollution, improve health outcomes, and decrease greenhouse gas emissions in rural areas of developing countries through the adoption of improved cooking stoves. This is largely supported by observational field studies and engineering or laboratory experiments. However, we provide new evidence, from a randomized control trial conducted in rural Orissa, India (one of the poorest places in India) on the benefits of a commonly used improved stove that laboratory tests showed to reduce indoor air pollution and require less fuel. We track households for up to four years after they received the stove. While we find a meaningful reduction in smoke inhalation in the first year, there is no effect over longer time horizons. We find no evidence of improvements in lung functioning or health and there is no change in fuel consumption (and presumably greenhouse gas emissions). The difference between the laboratory and field findings appears to result from households’ revealed low valuation of the stoves. Households failed to use the stoves regularly or appropriately, did not make the necessary investments to maintain them properly, and usage rates ultimately declined further over time. More broadly, this study underscores the need to test environmental and health technologies in real-world settings where behavior may temper impacts, and to test them over a long enough horizon to understand how this behavioral effect evolves over time.
Hanna, Rema, Sendhil Mullainathan, and Josh Schwartstein. 2012. “

Learning Through Noticing: Theory And Experimental Evidence In Farming

Existing learning models attribute failures to learn to a lack of data. We model a different barrier. Given the large number of dimensions one could focus on when using a technology, people may fail to learn because they failed to notice important features of the data they possess. We conduct a field experiment with seaweed farmers to test a model of "learning through noticing." We find evidence of a failure to notice: On some dimensions, farmers do not even know the value of their own input. Interestingly, trials show that these dimensions are the ones that farmers fail to optimize. Furthermore, consistent with the model, we find that simply having access to the experimental data does not induce learning. Instead, farmers change behavior only when presented with summaries that highlight the overlooked dimensions. We also draw out the implications of learning through noticing for technology adoption, agricultural extension, and the meaning of human capital.
Hanna, Rema, Eva Arceo, and Paulina Oliva. 2012. “

Does The Effect Of Pollution On Infant Mortality Differ Between Developing And Developed Countries? Evidence From Mexico City

Much of what we know about the marginal effect of pollution on infant mortality is derived from developed country data. However, given the lower levels of air pollution in developed countries, these estimates may not be externally valid to the developing country context if there is a nonlinear dose relationship between pollution and mortality or if the costs of avoidance behavior differs considerably between the two contexts. In this paper, we estimate the relationship between pollution and infant mortality using data from Mexico. We find that an increase of 1 parts per billion in carbon monoxide (CO) over the last week results in 0.0032 deaths per 100,000 births, while a 1 μg/m3 increase in particulate matter (PM10) results in 0.24 infant deaths per 100,000 births. Our estimates for PM10 tend to be similar (or even smaller) than the U.S. estimates, while our findings on CO tend to be larger than those derived from the U.S. context. We provide suggestive evidence that a non-linearity in the relationship between CO and health explains this difference.
Hanna, Rema, and Michael Greenstone. 2011. “

Environmental Regulations, Air And Water Pollution, And Infant Mortality In India

Using the most comprehensive data file ever compiled on air pollution, water pollution, environmental regulations, and infant mortality from a developing country, the paper examines the effectiveness of India’s environmental regulations. The air pollution regulations were effective at reducing ambient concentrations of particulate matter, sulfur dioxide, and nitrogen dioxide. The most successful air pollution regulation is associated with a modest and statistically insignificant decline in infant mortality. However, the water pollution regulations had no observable effect. Overall, these results contradict the conventional wisdom that environmental quality is a deterministic function of income and underscore the role of institutions and politics.
Khwaja, Asim Ijaz, Atif R Mian, and Abid Qamar. 2011. “

Bank Credit And Business Networks

”. Publisher's VersionAbstract
We construct the topology of business networks across the population of firms in an emerging economy, Pakistan, and estimate the value that membership in large yet diffuse networks brings in terms of access to bank credit and improving financial viability. We link two firms if they have a common director. The resulting topology includes a "giant network" that is order of magnitudes larger than the second largest network. While it displays "small world" properties and comprises 5 percent of all firms, it accesses two-thirds of all bank credit. We estimate the value of joining this giant network by exploiting "incidental" entry and exit of firms over time. Membership increases total external financing by 16.6 percent, reduces the propensity to enter financial distress by 9.5 percent, and better insures firms against industry and location shocks. Firms that join improve financial access by borrowing more from new lenders, particularly those already lending to their (new) giant-network neighbors. Network benefits also depend critically on where a firm connects to in the network and on the firm's pre-existing strength.
Chandra, Amitabh, and Jonathan S Skinner. 2011. “

Technology Growth And Expenditure Growth In Health Care

”. Publisher's VersionAbstract
In the United States, health care technology has contributed to rising survival rates, yet health care spending relative to GDP has also grown more rapidly than in any other country. We develop a model of patient demand and supplier behavior to explain these parallel trends in technology growth and cost growth. We show that health care productivity depends on the heterogeneity of treatment effects across patients, the shape of the health production function, and the cost structure of procedures such as MRIs with high fixed costs and low marginal costs. The model implies a typology of medical technology productivity: (I) highly cost-effective “home run” innovations with little chance of overuse, such as anti-retroviral therapy for HIV, (II) treatments highly effective for some but not for all (e.g. stents), and (III) “gray area” treatments with uncertain clinical value such as ICU days among chronically ill patients. Not surprisingly, countries adopting Category I and effective Category II treatments gain the greatest health improvements, while countries adopting ineffective Category II and Category III treatments experience the most rapid cost growth. Ultimately, economic and political resistance in the U.S. to ever-rising tax rates will likely slow cost growth, with uncertain effects on technology growth.
Pande, Rohini, and Abhijit Banerjee. 2009. “

Parochial Politics: Ethnic Preferences And Politician Corruption

This paper examines how increased voter ethnicization, de nied as greater voter preference for the party representing her ethnic group, a ects legislator quality. In situations where parties and politicians cannot commit to policies prior to the election, ethnicization reduces average winner quality for the pro-majority party, with the opposite true for the minority party. Overall, the average winner-loser quality gap reduces. These e ects increase with greater numerical dominance of the majority and are absent in jurisdictions with equal-sized voter groups. Empirical evidence from a survey on politician corruption in North India is remarkably consistent with our theoretical predictions.
Clingingsmith, David, Asim Ijaz Khwaja, and Michael Kremer. 2008. “

Estimating The Impact Of The Hajj: Religion And Tolerance In Islam's Global Gathering

”. Publisher's VersionAbstract
We estimate the impact on pilgrims of performing the Hajj pilgrimage to Mecca. Our method compares successful and unsuccessful applicants in a lottery used by Pakistan to allocate Hajj visas. Pilgrim accounts stress that the Hajj leads to a feeling of unity with fellow Muslims, but outsiders have sometimes feared that this could be accompanied by antipathy toward non-Muslims. We find that participation in the Hajj increases observance of global Islamic practices such as prayer and fasting while decreasing participation in localized practices and beliefs such as the use of amulets and dowry. It increases belief in equality and harmony among ethnic groups and Islamic sects and leads to more favorable attitudes toward women, including greater acceptance of female education and employment. Increased unity within the Islamic world is not accompanied by antipathy toward non-Muslims. Instead, Hajjis show increased belief in peace, and in equality and harmony among adherents of different religions. The evidence suggests that these changes are more a result of exposure to and interaction with Hajjis from around the world, rather than religious instruction or a changed social role of pilgrims upon return.
Pande, Rohini. 2007. “

Understanding Political Corruption In Low Income Countries

”. Publisher's VersionAbstract
Building on the large and growing empirical literature on the political behavior of individuals in low income countries this chapter seeks to understand corruption through the lens of political economy -- particularly in terms of the political and economic differences between rich and poor countries. Our focus is on the political behavior of individuals exposed to democratic political institutions. We review the existing literature on the determinants of individual political behavior to ask whether we can understand the choice of political actors to be corrupt and, importantly, of other individuals to permit it, as a rational response to the social or the economic environment they inhabit. We also discuss the implications of this view of corruption for anti-corruption policies.