Liam Wren-Lewis

This paper exploits quasi-random variation in the share of Black students across cohorts within US schools to investigate whether childhood interracial contact impacts the residential choices of Whites when they are adults. We find that, 20 years after exposure, Whites who had more Black peers of the same gender in their grade go on to live in census tracts with more Black residents. Further investigation suggests that this result is unlikely to be driven by economic opportunities or social networks. Instead, the effect on residential choice appears to come from a change in preferences among Whites.

This paper examines the impact of ethnic fractionalization on public service use by exploiting a major constitutional reform in Kenya. Following an important period of inter-ethnic conflict, responsibility for local health services was decentralized to 47 newly created county governments. Crucially, this changed the ethnic composition of the administrative area responsible for healthcare, while leaving the composition of the local population unchanged. Using an event-study design, we find that use of public clinics for births increased significantly after the reform, but only in counties that were relatively ethnically homogeneous. We also find a significant increase in the correlation between county ethnic fractionalization and a range of other measures of public health service use. Using within-county variation to investigate mechanisms, we find healthcare use increases were concentrated among individuals of the same ethnicity as members of the new county government executives. Overall, the results suggest that more ethnically homogeneous sub-national jurisdictions can rapidly increase public service use.

Relational contracts are typically modeled as being between a principal and an agent, such as a firm owner and a supplier. Yet, in a variety of organizations, relationships are overseen by an intermediary such as a manager. Such arrangements open the door for collusion between the manager and the agent. This paper develops a theory of such managed relational contracts. We show that managed relational contracts differ from principal–agent ones in important ways. First, kickbacks from the agent can help solve the manager’s commitment problem. When commitment is difficult, this can result in higher agent effort than the principal could incentivize directly. Second, making relationships more valuable enables more collusion and hence can reduce effort. We also analyze the principal’s delegation problem and show that she may or may not benefit from entrusting the relationship to a manager.

Dans les pays du Sud où une grande partie de la population travaille dans l’agriculture, sortir les travailleurs du secteur agricole relativement improductif peut être une clé pour améliorer leur niveau de vie. Cette « transformation structurelle » a caractérisé la trajectoire de développement de presque tous les pays développés. Pour accélérer le processus et empêcher les zones rurales de prendre du retard en termes économiques, les pays investissent souvent massivement dans les infrastructures. De tels projets contribuent-ils à transformer les zones agricoles ? L’analyse s’appuie largement sur le cas de l’Inde. Si les investissements à grande échelle dans les infrastructures rurales, notamment les routes, ont eu des effets positifs, leur impact en termes de bien-être et de consommation est très hétérogène. En particulier, seuls les villages ayant bénéficié à la fois d’infrastructures routières et électriques semblent avoir vu leur consommation par habitant augmenter. Il faudrait donc regrouper les programmes complémentaires et les cibler sur des zones spécifiques pour que les investissements soient efficaces.

Complementarities between infrastructure projects have been understudied. This paper examines interactions in the impacts of large-scale road construction, electrification, and mobile phone coverage programs in rural India. We find strong evidence of complementary impacts between roads and electricity on agricultural production: dry season cropping increases significantly when villages receive both, but not when they receive one without the other. These complementarities are associated with a shift of cropping patterns towards market crops and with improved economic conditions. In contrast, we find no consistent evidence of complementarities for the mobile coverage program.

This paper exploits quasi-random variation in the share of Black students across cohorts within US schools to investigate whether interracial contact in childhood impacts the residential choices of Whites in adulthood. We find that, 20 years after exposure, Whites who had more Black peers of the same gender in their grade go on to live in census tracts with more Black residents. Further investigation suggests that this result is unlikely to be driven by economic opportunities or social networks. Instead, the effect on residential choice appears to come from a change in preferences among Whites.

A large share of important economic interactions take place in a non-simultaneous fashion – i.e. one party takes an action in the expectation that another actor will behave as promised in the future. Such transactions occur between individuals, firms, and states. For these transactions to be undertaken, participants must believe that the counterparty will behave as promised – i.e. they need trust. The central question running through my work is “how should policy respond to a lack of trust?” Part of the answer to this question is clearly “build more trust”, and hence an important sub-theme of my work is examining which policies may be conducive to trustbuilding. In many circumstances, however, there are fundamental constraints on the extent to which parties may trust one another. In these cases the relevant question therefore becomes “how can policy mitigate the negative consequences of lack of trust?

Relational contracts are typically modeled as being between a principal and an agent, such as a firm owner and a supplier. Yet, in a variety of organizations, relationships are overseen by an intermediary such as a manager. Such arrangements open the door for collusion between the manager and the agent. This paper develops a theory of such managed relational contracts. We show that managed relational contracts differ from principal-agent ones in important ways. First, kickbacks from the agent can help solve the manager’s commitment problem. When commitment is difficult, this can result in higher agent effort than the principal could incentivize directly. Second, making relationships more valuable enables more collusion and hence can reduce effort. We also analyze the principal’s delegation problem and show that she may or may not benefit from entrusting the relationship to a manager.