Publications

Abstract

In Shared Medical Appointments (SMAs), patients with similar conditions meet the physician together and each receives one-on-one attention. SMAs can improve outcomes and physician productivity. Yet privacy concerns have stymied adoption. In physician-deprived nations, patients’ utility from improved access may outweigh their disutility from loss of privacy. Ours is to our knowledge the first SMA trial for any disease, in India, where doctors are scarce. In a 1,000-patient, single-site, randomized controlled trial at Aravind Eye Hospital, Pondicherry, we compared SMAs and one-on-one appointments, over four successive visits, for patients with glaucoma. We examined patients’ satisfaction, knowledge, intention-to-follow-up, follow-up rates, and medication compliance rates (primary outcomes) using intention-to-treat analysis. Of 1,034 patients invited between July 12, 2016 –July 19, 2018, 1,000 (96.7%) consented to participate, and were randomly assigned to either SMAs (N_SMA = 500) or one-on-one appointments (N_1-1 = 500). Patients who received SMAs showed higher satisfaction (Mean_SMA = 4.955 (SD 0.241), Mean_1-1 = 4.920 (SD 0.326); difference in means 0.035; 95% CI, 0.017–0.054, p = 0.0002) and knowledge (Mean_SMA = 3.416 (SD 1.340), Mean_1-1 = 3.267 (SD 1.492); difference in means 0.149; 95% CI, 0.057–0.241, p = 0.002) than patients who received one-on-one appointments. Across conditions, there was no difference in patients’ intention-to-follow-up (Mean_SMA = 4.989 (SD 0.118), Mean_1-1 = 4.986 (SD 0.149); difference in means 0.003; 95% CI, -0.006–0.012, p = 0.481) and actual follow-up rates (Mean_SMA = 87.5% (SD 0.372), Mean_1-1 = 88.7% (SD 0.338); difference in means -0.012; 95% CI, -0.039–0.015, p = 0.377). Patients who received SMAs exhibited higher medication compliance rates (Mean_SMA = 97.0% (SD 0.180), Mean_1-1 = 94.9% (SD 0.238); difference in means 0.020; 95% CI, 0.004–0.036, p = 0.013). SMAs improved satisfaction, learning, and medication compliance, without compromising follow-up rates or measured clinical outcomes. Peer interruptions were negatively correlated with patient satisfaction in early-trial SMAs and positively correlated with patient satisfaction in later-trial SMAs.

Abstract

Microentrepreneurs represent the most common type of business in the world, and marketing is a primary means by which they earn their livelihoods. They are especially numerous in emerging markets, and many live precarious lives characterized by poverty and potentially devastating exogenous shocks. This paper examines the marketing practices of microentrepreneurs by studying grocery retailers in a large slum in Cairo, Egypt. Employing detailed data on the marketing practices of these retailers, the paper examines why some microentrepreneurs engage in innovation in their marketing practices (and perform better), whereas others fail to do so. We highlight the causal effect of an important, but rarely studied, factor—informal property rights—on innovation in marketing practices among microentrepreneurs. Because few microentrepreneurs in the context we study have access to formal property rights, the threat of expropriation looms large in their lives. We show that those microentrepreneurs who possess their stores (without actually owning them) are substantially less likely to innovate in their marketing practices than those who lease their stores. We make use of an exogenous shock to property-rights laws to assess the causal impact of informal property rights on innovation in marketing practices.

Abstract

The African people and leaders^1,2 have long seen education as a driving force of development and liberation, a view shared by international institutions^3,4, as schooling has large economic and non-economic returns, particularly in low-income settings⁵. In this study, we examine the educational progress across faiths throughout postcolonial Africa, home to some of the world’s largest Christian and Muslim communities. We construct comprehensive religion-specific measures of intergenerational mobility in education using census data from 2,286 districts in 21 countries and document the following. First, Christians have better mobility outcomes than Traditionalists and Muslims. Second, differences in intergenerational mobility between Christians and Muslims persist among those residing in the same district, in households with comparable economic and family backgrounds. Third, although Muslims benefit as much as Christians when they move early in life to high-mobility regions, they are less likely to do so. Their low internal mobility accentuates the educational deficit, as Muslims reside on average in areas that are less urbanized and more remote with limited infrastructure. Fourth, the Christian–Muslim gap is most prominent in areas with large Muslim communities, where the latter also register the lowest emigration rates. As African governments and international organizations invest heavily in educational programmes, our findings highlight the need to understand better the private and social returns to schooling across faiths in religiously segregated communities and to carefully think about religious inequalities in the take-up of educational policies.

Abstract

We identify novel technologies using textual analysis of patents, job postings, and earnings calls. Our approach enables us to identify and document the diffusion of 29 disruptive technologies across firms and labor markets in the U.S. Five stylized facts emerge from our data. First, the locations where technologies are developed that later disrupt businesses are geographically highly concentrated, even more so than overall patenting. Second, as the technologies mature and the number of new jobs related to them grows, they gradually spread geographically. While initial hiring is concentrated in high-skilled jobs, over time the mean skill level in new positions associated with the technologies declines, broadening the types of jobs that adopt a given technology. At the same time, the geographic diffusion of low-skilled positions is significantly faster than higher-skilled ones, so that the locations where initial discoveries were made retain their leading positions among high-paying positions for decades. Finally, these pioneer locations are more likely to arise in areas with universities and high skilled labor pools.

Abstract

This paper studies the economic impacts of carbon pricing. Exploiting institutional features of the European carbon market and high-frequency data, I document that a tighter carbon pricing regime leads to higher energy prices, lower emissions and more green innovation. This comes at the cost of a fall in economic activity, which is borne unequally across society: poorer households lower their consumption significantly while richer households are less affected. The poor are more exposed because of their higher energy share and, importantly, also experience a larger fall in income. Targeted fiscal policy can help alleviate these costs while maintaining emission reductions.

Abstract

This paper presents market-based evidence that President Trump influences expectations about monetary policy. The main estimates use tick-by-tick fed funds futures data and a large collection of Trump tweets criticizing the conduct of monetary policy. These collected tweets consistently advocate that the Fed lowers interest rates. Identification in our high-frequency event study exploits a small time window around the precise time stamp for each tweet. The average effect of these tweets on the expected fed funds rate is strongly statistically significant and negative, with a cumulative effect of around negative 10 bps. Therefore, we provide evidence that market participants believe that the Fed will succumb to the political pressure, which poses a significant threat to central bank independence.

Abstract

We model the building of a city, estimate parameters of the model, and calculate welfare losses from institutional frictions encountered in changing land-use. We distinguish formal and slum construction technologies; in contrast to slums, formal structures can be built tall, are durable, and non-malleable. As the city grows areas are initially developed informally, then formally, and then redeveloped periodically. Slums are modelled as a technology choice; however, institutional frictions in land markets may hinder their conversion to formal usage that requires secure property rights. Using unique data on Nairobi for 2003 and 2015, we develop a novel set of facts that support assumptions of the model, estimate all parameters of the model, and calculate welfare losses of conversion frictions. We track the dynamic evolution of the city and compare it with model predictions. In the core city formal sector, about a third of buildings were torn down over 12 years and replaced by buildings on average three times higher. For slums in older areas near the centre, even after buying out slumlords, overcoming institutional frictions would yield gains amounting to about $$18,000 per slum household, thirty times typical annual slum rent payments.

Abstract

We show that history can explain the geographic concentration of investment over and above traditional agglomerative forces, geography, and expectations. We use spatial variation in direct and indirect British rule to identify differences in historical circumstances. Using this within-country variation in historical circumstances, combined with a local identification approach and instrumental variable strategy, we explain the spatial differences in investment. Differences in historical origins can explain 13% of total geographic variation in investment. Moreover, investment is 8-10% lower in direct ruled areas. Our results indicate that history can have long-run consequences through its effect on economic organizations and state capacity.

Abstract

Africa’s demand for urban housing is soaring, even as it faces a proliferation of slums. In this setting, can modest infrastructure investments in greenfield areas where people subsequently build their own houses facilitate long-run neighborhood development? We study Sites and Services projects implemented in seven Tanzanian cities during the 1970s and 1980s, and we use a spatial regression discontinuity design to compare greenfield areas that were treated (de novo) with nearby greenfield areas that were not. We find that by the 2010s, de novo areas developed into neighborhoods with larger, more regularly laid-out buildings and better-quality housing.

Abstract

The US Food and Drug Administration (FDA) expanded access pathway allows patients with life-threatening or serious conditions to access investigational drugs outside of trials, under certain conditions. The 21st Century Cures Act (“Cures Act”) requires certain drug companies to publicly disclose their expanded access policies. We characterized the proportion of applicable US biopharmaceutical companies, with an oncology related drug, implementing Cures Act requirements for expanded access policies and whether available policies contain the information described in the Act. We found about one-third of applicable biopharmaceutical companies (32%, 140/423) implemented the Cures Act requirement to have a public expanded access policy. Less than one-third of public policies contained all described information (31%, 44/140). Larger companies and those with at least one drug receiving an FDA expedited designation (59% vs. 21%; P < 0.001), or at least one FDA-approved drug (57% vs. 28%; P < 0.001) were more likely to have a public policy. Our results suggest the Cures Act may be having a limited impact on its goals of supporting timely medical decisions and closing informational gaps for patients and doctors around expanded access to investigational oncology therapies, especially for products sponsored by smaller and newer companies.

Abstract

Do informal social ties connecting inventors across distant places promote knowledge flows between them? To measure informal ties, we use a new and direct index of social connectedness of regions based on aggregate Facebook friendships. We use a well-established identification strategy that relies on matching inventor citations with citations from examiners. Moreover, we isolate the specific effect of informal connections, above and beyond formal professional ties (co-inventor networks) and geographic proximity. We identify a significant and robust effect of informal ties on patent citations. Further, we find that the effect of geographic proximity on knowledge flows is entirely explained by informal social ties and professional networks. We also show that the effect of informal social ties on knowledge flows is greater for new entrepreneurs or ‘garage inventors’, for older or ‘forgotten’ patents, and for flows across distant technology fields. It has also become increasingly important over the last two decades.

Abstract

This paper studies whether tax policies in developed nations affect developing economies through cross-border investments by multinational firms. We study firm investment responses to a major U.K. tax reform that drastically reduced the income tax burden for U.K.-based firms. Our identification strategy compares the investment outcomes of U.K. multinational firms in Africa to those of other multinationals with similar ties to Africa but not subject to the large U.K. tax changes that started in 2009. Difference-in-differences estimates show that U.K. multinational firms increased their subsidiary presence in sub-Saharan Africa by 17-26 percent following the U.K. reform. Exploiting location-specific nighttime luminosity data as well as local data from the African Demographic and Health Surveys, we also document increased economic activity and higher employment rates of African citizens within close proximity of local U.K.-owned subsidiaries. These effects are confirmed using novel data on local wealth. Our findings imply that, beyond the goal of motivating home country investment, developed countries’ corporate tax policies impact developing nations.

Abstract

Justice-impacted people face significant obstacles to employment. This article explores an alternative pathway for these individuals to find work and income: entrepreneurship. While anecdotal evidence suggests that entrepreneurship is common among people with criminal histories, it remains both theoretically and empirically underexamined. I conduct a synthesis of recent research to assess the viability of entrepreneurship as a path to reintegration for returning citizens. I highlight findings on the prevalence of entrepreneurial entry, the underlying mechanism behind entrepreneurship, the economic and social consequences of entrepreneurship, and the barriers and challenges that re-entering entrepreneurs face. Finally, I draw attention to key policy implications and suggest new initiatives that can help enhance the viability of entrepreneurship as a re-entry strategy for justice-involved individuals.

Abstract

Information on willingness-to-pay is key for public pricing and allocation of services but not easily collected. Studying land titles in Dar-es-Salaam, we ask whether local leaders know and will reveal plot owners’ willingness-to-pay. We randomly assign leaders to predict under different settings then elicit owners’ actual willingness-to-pay. Demand is substantial, but below exorbitant fees. Leaders can predict the aggregate demand curve and distinguish variation across owners. Predictions worsen when used to target subsidies, but adding cash incentives mitigates this. Finally, we demonstrate that leader-elicited information can improve the public pricing of title deeds, raising uptake while maintaining public funds.

Abstract

This thesis is a contribution to macroeconomics and macro-finance research. It focuses on two areas, the interactions between debt markets and the macroeconomy, in the first two chapters, and consumption heterogeneity’s role in the transmission of shocks, in the third.

The first chapter is my job market paper, “Monetary Policy and the Maturity Structure of Public Debt”. It studies the mediating impact of the maturity structure of public debt in the transmission of monetary policy shocks to economic activity. A longer debt maturity attenuates greatly the effect of monetary policy: going from the average historical duration of US debt to very short term debt doubles the impact of a rise of the policy rate on output. A similar result holds in UK data. There is no differential effect on inflation. I show that these effects can be traced back to a quantitatively important financing channel. A model featuring an interaction between an empirically estimated primary market friction and a standard financial accelerator is able to account for these facts.

The second chapter of the thesis is “The Fiscal Consequences of Missing an Inflation Target”. This is a joint work with Helene Rey. We show, in Euro Area countries and in the US, the effect of the reliability of central banks’ monetary policy on public finances. When a credible central bank misses its inflation target, this has large fiscal consequences for the fiscal authority. These misses are quantitative sizable in the past low inflation decade, especially for countries with a high level and a high maturity of public debt. We link our results to the optimum currency area literature as the monetary-fiscal nexus is key to the functioning of the Euro Area: the ECB sets monetary policy for sovereigns with heterogeneous debt profiles.

The third chapter of my thesis, “LESS is MORE: Consumer Spending and the Size of Economic Stimulus Payments”, is a joint work with Paolo Surico. We study the consumption response to unexpected transitory income gains of different size, using hypothetical survey questions. Affluent households exhibit a higher Marginal Propensity to Consume (MPC) out of large gains while families with low cash-on-hand display a higher MPC out of small gains. The spending of higher earners is consistent with the predictions of a model with non-homothetic preferences on consumption, while spending of low-income families can be accounted for by borrowing constraints. Our results suggest that, for a given level of public spending, a fiscal transfer of smaller size paid to a larger group of low-income households stimulates aggregate consumption more than a larger transfer paid to a smaller group.

Abstract

We investigate the evolution of gender norms for 160 years in the US. Socioeconomists have posited two fundamental and widely debated theories on the evolution of cultural norms across time. One argues that cultural norms should converge across time as economies become more advanced and integrated, whereas the other states that cultural traits are highly persistent, passed down from generation to generation. These theories remain untested due to a lack of granular and high-frequency data over a longer time period. We develop a novel unsupervised machine learning methodology and apply it to 193 million pages of local newspaper text to produce localised attitudes towards women on four dimensions: career vs family, attitudes towards abortion, attitudes towards feminism/suffrage, and violence against women. We establish novel facts on the evolution of attitudes across time. First, attitudes are less persistent than the existing literature hypothesises. Second, the persistence varies considerably across regions and dimensions. Third, attitudes exhibit cyclical patterns. Fourth, regional variation in attitudes decreases considerably over time and has fallen between 64% to 79%. Fifth, a decrease in transport costs that allows for easier information sharing is associated with a homogenisation of the norms.

Abstract

We construct novel text-based measures of firm-level cyber risk exposure based on quarterly earnings calls of 12,000+ firms from 85 countries over 20+ years. We categorize each cyber-related discussion into topics that capture sentiment, monetary loss, country names, etc. We document new facts on the worldwide rise of cyber risk and its industrial and geographical composition. We characterize most affected firms and show that our indices can predict future cyberattacks. Cyber risk exposure has significant direct and contagion effects on stock returns. Finally, there is a factor structure in our firm-level measures and shocks to the common factor are priced.

Abstract

Problem Definition: Clients and service providers alike often consider one-on-one service delivery to be ideal, assuming — perhaps unquestioningly — that devoting individualized attention best improves client outcomes. In contrast, in shared service delivery, clients are served in batches and the dynamics of group interaction could lead to increased client engagement — which could improve outcomes. However, the loss of privacy and personal connection might undermine engagement.

Practical Relevance: The engagement dynamics in one-on-one and shared delivery models have not been rigorously studied. To the extent that shared delivery may result in comparable or better engagement than one-on-one delivery, service providers in a broad array of contexts may be able to create more value for clients by delivering service in batches.

Methodology: We conducted a randomized controlled trial with 1,000 patients who were undergoing glaucoma treatment over a three-year period at a large eye hospital. Using verbatim and behavioral transcripts from over 20,000 minutes of video recorded during our trial, we examine how shared medical appointments (SMAs) — in which patients are served in batches — impact engagement.

Results: Patients who experienced SMAs asked 33.33% more questions per minute, made 8.63% more non-question comments per minute, and exhibited higher levels of non-verbal engagement across a wide array of measures (attentiveness, positivity, head wobbling or `talai taḷḷāṭṭam’ in Tamil — a South Indian gesture to signal agreement or understanding — eye contact and end-of-appointment happiness), relative to patients who attended one-on-one appointments.

Managerial Implications: These results shed light on the potential for shared service delivery models to increase client engagement and enhance service performance.

Abstract

We study the real effects of environmental activist investing. Using plant-level data, we find that targeted firms reduce their toxic releases, greenhouse gas emissions, and cancer-causing pollution. Improvements in air quality within a one-mile radius of targeted plants suggest potentially important externalities to local economies. These improvements come through increased capital expenditures on new abatement initiatives. We rule out alternative explanations of decline in production, reporting biases, and forms of selection, while also providing evidence supporting the external validity of environmental activism. Overall, our study suggests that engagements are an effective tool for long-term shareholders to address climate change risks.

Abstract

Multinationals are often considered a tool through which economic shocks originating in a region get magnified. This paper, in contrast, shows that elevated economic policy uncertainty (EPU) in a country is associated with increase in investment by a firm in other regions. I find that (multinational) firms hold back investment in a country subjected to higher EPU, which they reallocate to projects in other countries. I find the impact to be higher for firms with tighter financial constraints. I also find that the reallocation is directed more towards countries that provide a better legal environment. The study uses establishment-level data of mining firms as a laboratory. Limited input–output linkage across mines allows me to study the impact caused particularly through the allocation decision of firms. The empirical strategy exploits variations in: i) parent country of mines operating in the same country; & ii) country of operation of mines owned by same firm. Overall, my findings highlight that multinationals could potentially stabilize the escalation of regional policy uncertainty shocks to global crisis.

Abstract

Does comparative advantage explain legislators’ support for trade liberalization? We use data on potential crop yields as determined by weather and soil characteristics to derive a new plausibly exogenous measure of comparative advantage in agriculture for each district in the United States. Evidence shows that comparative advantage in agriculture predicts how legislators vote on the ratification of preferential trade agreements in Congress. We show that legislators in districts with high agricultural comparative advantage are more likely to mention that trade agreements are good for agriculture in House floor debates preceding roll call votes on their ratifications. Individuals living in the same districts are also more likely to support free trade. Our analysis and results contribute to the literature on the political economy of trade and its distributional consequences and to our understanding of the economic determinants of legislators’ voting decisions.

Abstract

This paper studies the labor market consequences of ethnic politics in African democracies. Using data from 15 countries, 32 elections, and more than 400,000 individuals, we implement a regression discontinuity design that compares individuals from ethnicities connected to parties at the margin of electing a local representative in the national parliament. Having a local ethnic party politician in parliament increases the likelihood of being employed by 2-3 pp. The available evidence supports the hypothesis that this effect results from strategic interactions between politicians and traditional leaders, the latter being empowered to allocate land and agricultural jobs in exchange for votes.

Abstract

We construct novel text-based measures of firm-level cyber risk exposure based on quarterly earnings calls of 12,000+ firms from 85 countries over 20+ years. We categorize each cyber-related discussion into topics that capture sentiment, monetary loss, country names, etc. We document new facts on the worldwide rise of cyber risk and its industrial and geographical composition. We characterize most affected firms and show that our indices can predict future cyberattacks. Cyber risk exposure has significant direct and contagion effects on stock returns. Finally, there is a factor structure in our firm-level measures and shocks to the common factor are priced.