Research

My research statement is here and a summary of my research can be found here 

Publications 

Zero-sum Environments, the Evolution of Effort-Suppressing Beliefs, and Economic Development

Abstract: We study the evolution of belief systems that suppress productive effort, such as beliefs about envy, witchcraft, the importance of luck for success, or disdain for competitive effort. In our framework, demotivating beliefs evolve when interactions are zero-sum, i.e., one person's gain comes at the expense of others. They improve material welfare but reduce subjective well-being. The model delivers testable predictions about the relationship between the degree of zero-sumness, demotivating beliefs, material welfare, subjective well-being, and long-run economic development. We find that the predictions are supported by data from two samples in the Democratic Republic of Congo, as well as global evidence from the World Values Survey and the European Values Study.

Supermodular Bureaucrats: Evidence from Randomly Assigned Tax Collectors in the DRC 

Summary for a broader audience: VoxDev

Abstract: The assignment of workers to tasks and teams is a key margin of firm productivity and a potential source of state effectiveness. This paper investigates whether a low-capacity state can increase its tax revenue by improving the assignment of its tax collectors. We study the two-stage random assignment of property tax collectors into teams and to neighborhoods in a large Congolese city. The optimal assignment involves positive assortative matching on both dimensions: high (low) ability collectors should be paired together, and high (low) ability teams should be paired with high (low) payment propensity households. Positive assortative matching stems from complementarities in collector-to-collector and collector-to-household match types. We provide evidence that these complementarities reflect in part high-ability collectors exerting greater effort when matched with other high-ability collectors. According to our estimates, implementing the optimal assignment would increase tax compliance by 3.75 percentage points and revenue by 38% relative to the status quo (random) assignment. Alternative policies, such as replacing low-ability collectors with new ones of average ability or increasing collectors' performance wages, are likely incapable of achieving a similar revenue increase.

Property Rights and Social Institutions: How Local Institutions and Chiefs Shape Land Formalization in Urban Africa

Abstract: Formal property rights to land remain rare in sub-Saharan Africa. We argue that social institutions shape citizens' demand for land formalization. When offered the opportunity to formalize, citizens weigh the insurance and tenure-security benefits of informal institutions against their monetary and social obligations. We study a randomized land titling program in a large Congolese city that sharply reduced the costs of acquiring a title. The program markedly increased both initiation and receipt of titles. Demand was strongest among citizens more engaged in social institutions and closer to city chiefs, yet such ties did not predict completion. Program assignment also reduced participation in horizontal social institutions and worsened evaluations of chiefs. These findings suggest that, in urban settings where land values are higher and social institutions more costly, citizens seek to exit costly social institutions when formal alternatives become available, illustrating how formalization can reshape engagement with informal authority.

 The State Capacity Ceiling on Tax Rates: Evidence from Randomized Tax Abatements in the DRC 

Summary for a broader audience: Econimate (video), VoxDev, JPAL (video), JPAL, World Bank

Abstract: This paper investigates how tax rates and tax enforcement jointly impact fiscal capacity in low‐income countries. We study a policy experiment in the D.R. Congo that randomly assigned 38,028 property owners to the status quo tax rate or a rate reduction. This variation in tax liabilities reveals that the status quo rate lies above the revenue‐maximizing tax rate (RMTR). Reducing rates by about one‐third would maximize government revenue by increasing tax compliance. We then exploit two sources of variation in enforcement—randomized enforcement letters and random assignment of tax collectors—to show that the RMTR increases with enforcement. Including an enforcement message on tax letters or replacing tax collectors in the bottom quartile of enforcement capacity with average collectors would raise the RMTR by about 40%. Tax rates and enforcement are thus complementary levers. Jointly optimizing tax rates and enforcement would lead to 10% higher revenue gains than optimizing them independently. These findings provide experimental evidence that low government enforcement capacity sets a binding ceiling on the revenue‐maximizing tax rate in some developing countries, thereby demonstrating the value of increasing tax rates in tandem with enforcement to expand fiscal capacity.

Local Elites as State Capacity: How City Chiefs Use Local Information to Increase Tax Compliance in the Democratic Republic of the Congo

Summary for a broader audience: AEA highlights, VoxDev, JPAL (video)

Abstract: This paper investigates the trade-offs between local elites and state agents as tax collectors in low-capacity states. We study a randomized policy experiment assigning neighborhoods of a large Congolese city to property tax collection by city chiefs or state agents. Chief collection raised tax compliance by 3.2 percentage points, increasing revenue by 44 percent. Chiefs collected more bribes but did not undermine tax morale or trust in government. Results from a hybrid treatment arm in which state agents consulted with chiefs before collection suggest that chief collectors achieved higher compliance by using local information to more efficiently target households with high payment propensities rather than by being more effective at persuading households to pay conditional on having visited them.

Earlier Work

Income Concentration in British India, 1885-1946 with Facundo Alvaredo and Guilhem Cassan, Journal of Development Economics, 2017, 127.

The Association Between Income and Life Expectancy in the United States, 2001-2014 with  Raj Chetty,  Micheal Stepner, Sarah Abraham, Shelby Lin, Ben Scuderi , Nick Turner and David Cutler, The Journal of the American Medical Association, 2016, 315(14).

Working Papers

Does Progressivity Raise Tax Capacity? Experimental Evidence from the D.R. Congo (draft coming soon)

Abstract: Progressive taxation is a defining feature of high-income countries' tax systems, but developing countries typically rely on less progressive instruments. We study the introduction of progressive property taxation in a large Congolese city through a citywide field experiment conducted in partnership with the provincial government. Neighborhoods were randomly assigned to either a progressive or a proportional schedule. The progressive schedule increased total revenue by 55% relative to the proportional one. Revenue gains occured throughout the property value distribution, but through different mechanisms: at the top, higher statutory rates mechanically outweighed modest compliance losses, while at the bottom, lower rates induced large compliance gains that more than offset the mechanical revenue loss. Cross-randomized information treatments show that taxpayers respond primarily to their own rates, not to others' rates or to the perceived fairness of the overall tax schedule. Effective tax rates (ETRs) – taxes paid as a share of property value – decline with property value under all tax systems and are most regressive under the progressive schedule. However,  enforcement targeting higher-value properties flips this relationship, suggesting that investments in enforcement capacity can help align effective with statutory progressivity.

Redrawing Group Boundaries: Religious Institutions and Identity Formation in Colonial Congo (draft coming soon)

Abstract:  How are group identities formed and transformed? This paper studies a historical institution that attempted to remake the boundaries of moral obligation in colonial Congo. Christian missions, whose effects on religious conversion and religiosity are well documented, sought to weaken allegiance to kin, coethnics, and customary authorities and to attach converts to a Christian moral community. I combine newly digitized data on mission locations with an original survey of 975 respondents in Kananga, measuring attitudes toward family, coethnics, church members, Christians, and non-Christians; social network composition; referral behavior in a job experiment; and moral values. To address endogenous mission placement, I compare exposure to active missions with two counterfactuals: missions that were founded but abandoned, and simulated locations that were suitable for missions but never selected. Exposure to missions reduced favoritism toward kin and coethnics and made social networks and job referrals less organized around family and ethnicity. It also reduced communal moral values, such as in-group loyalty and respect for authority, but did not increase universal moral concern. Instead, identity and moral obligation were redirected toward religious affiliation, generating stronger favoritism toward fellow church members and Christians. Effects are strongest where missionary activity involved catechists, teachers, and schools, but not health facilities. The findings show that institutions can durably change identity not by dissolving group boundaries, but by remapping them.

Does Collecting Taxes Erode the Responsiveness of Informal Leaders? Evidence from the D.R.C

Abstract: In weak states, delegating tax collection to informal leaders may raise revenue but risks undermining their responsiveness to local preferences. We investigate this tradeoff by exploiting whether city chiefs in D.R. Congo were randomly assigned to collect property taxes. To measure responsiveness, we study chiefs' distribution of resources in a government cash transfer program. In line with citizens' preferences, chiefs who collected taxes allocated more program benefits to poorer households. The results help allay concerns about the effects of chief tax collection on local governance and highlight a synergy between the information needed by low-capacity states for taxation and transfers.

Delegating Tax Collection Does Not Adversely Affect Demand for Accountability: Experimental Evidence from the D.R. Congo

Abstract: Taxation can catalyze citizen participation and demand for good governance, yet little is known about whether delegating tax collection to local non-state actors – a common practice in developing countries – dampens such accountability demands. We examine a policy experiment in which 101 neighborhoods in Kananga, D.R. Congo, were randomly assigned to property tax collection by state agents or local city chiefs. We combine this source of variation with a novel behavioral measure of demand for accountability in which 2,631 citizens could request community audits of an antipoverty program implemented jointly by the government and city chiefs. We find no evidence that the type of agent in charge of tax collection differentially affected citizens' propensity to hold the state or chief accountable. The results indicate that low-capacity states can raise revenue by delegating tax collection to local leaders in urban areas without adverse consequences for bottom-up accountability.

Barriers to Formalization: Evidence from Six Randomized Experiments on Transaction Costs, Public Services, and Taxation in the Global South

Abstract: We present six harmonized RCTs to assess whether removing bureaucratic hurdles can encourage individuals to engage formally with the state in six countries in the Global South. Recent work has argued that the trade-offs inherent to formalization are more acceptable to individuals when formaliza-tion is tied to publicly-derived benefits, such as access to legal recourse in disputes, public services, or public utilities. Yet, even in these cases, bureau-cratic barriers to formalization might be insurmountable. So far, disconnected research on different bureaucratic procedures has led to contrasting conclu-sions about how entry costs affect formalization. Our interventions involved in-person assistance to reduce the upfront transaction costs of dealing with the bureaucracy in three types of policy domain: titling property, registration of small businesses, and access to public utilities (i.e., municipal water) and pub-lic services (i.e., garbage collection). A meta-analysis shows that the average effect of these interventions on individuals’ formalization, tax payment, and access to services is indistinguishable from zero. We also find substantial het-erogeneity in individuals’ intent to undertake and complete the bureaucratic process. Across policy domains, individuals are more willing to bear formal-ization’s downstream costs when the benefits are individual. Our results also suggest that local bureaucratic incentives must be aligned for demand-side interventions to work.

Work In Progress

Illegitimate Taxation: Evidence from 40,000 Colonial Documents 

Abstract: This paper studies how tax legitimacy shapes resistance to taxation. We examine colonial Nigeria, where British authorities introduced broadly similar taxes under a common colonial regime but confronted sharply different pre-existing fiscal systems and sources of legitimacy. Using 40,852 colonial administrative documents, we apply large language models to construct measures of tax sentiment and tax complaints, and validate them against a human-coded subsample. In a spatial regression discontinuity design at the historical boundary of the Sokoto Caliphate, we find more negative tax sentiment and higher complaint rates in areas where colonial taxation displaced a centralized fiscal order rooted in established moral and religious authority. These patterns are consistent with contestation of the colonial state’s right to tax rather than differences in tax instruments or burden, enforcement, administrative capacity, or colonial public goods provision. We also document persistence today using Afrobarometer measures of tax legitimacy, including beliefs about whether the tax authority has the right to make people pay taxes. The findings identify legitimacy as a distinct determinant of tax resistance and a key constraint on fiscal capacity.

State Building via Punitive and Restorative Justice: Evidence from the D.R. Congo

Abstract: Resolving disputes is integral to the accumulation of state capacity. Yet policymakers often privilege fiscal capacity building in fragile states over legal capacity building. In this project, we study a low-capacity state—the D.R. Congo—seeking to establish legal authority and how its efforts to do so shape citizens’ demand for the state. Specifically, we examine the randomized rollout of a legal capacity-building program implemented at scale in the city of Kananga (DRC) by the Ministry of Justice and a local NGO. This program has (1) a “punitive” legal capacity-building arm in which state lawyers serve as neighborhood legal representatives with subsidized services and (2) a “restorative” legal capacity-building arm in which customary chiefs perform these same functions. We will examine effects on property rights security, crime, violence, and citizens’ willingness to pay for the formal state. 

Misperceptions of Group Inequality and Support for Redistribution and Sectarian Politics: Experimental Evidence from Lebanon

Abstract: Economic inequality in Lebanon is among the highest in the world, yet political cleavages remain overwhelmingly sectarian rather than class-based. We propose a demand-side explanation: citizens misperceive the extent of inequality between religious groups, weakening support for cross-sectarian redistribution. Using a representative survey of 3,300 adults in Greater Beirut and an embedded randomized experiment, we first document that Christians, Sunnis, and Shias all overestimate income differences across sects despite very similar economic distributions. We then expose respondents to a short video — combining factual statistics and an empathic narrative — emphasizing that poverty and wealth are shared across sects. The treatment corrects beliefs, reduces perceived intergroup inequality, and increases support for redistributive policies. These effects operate through stronger identification with social class and greater anger toward economic elites. However, political preferences and costly civic behaviors remain unchanged, reflecting the persistence of sectarian attachments and clientelistic networks. Our findings show that misperceptions of group inequality can help explain the weakness of class-based politics in highly divided societies.