Knowledge that Transforms

A principal (such as a centrist political party) can partially influence the allocation of power between two competing parties. The principal is closer to one party, the ``Friend'', than to the other, the ``Enemy''. The principal's optimal contract initially seeks to exclude the Enemy. However, once the Enemy gains power, the principal embraces him in exchange for policy moderation. Moderation also disciplines the Friend, inducing him to move closer to the principal's preferred policy. Principals close to the Friend fully embrace the Enemy; more centrist principals divide their support. Commitment benefits the principal only if she is close to the Friend and parties value power little.

We document that the source of funds for paying health insurance premiums has a dramatic impact on plan choices. We focus on the MediSave program in Singapore, a medical savings account that is used to pay out-of-pocket medical spending. Residents can also pay their health insurance premiums with cash or MediSave funds, but are subject to limits that vary by age and over time. By exploiting variations in those limits, we consistently find that when individuals are able to pay their health insurance premiums with MediSave funds, they are less price sensitive and more willing to enroll in more generous plans. We develop and estimate a mental accounting model which explains these patterns. We embed and reject alternative explanations such as hassle costs and liquidity constraints. We then extend this model and show that mental accounting can explain much, but not all, of the misweighting of premiums relative to out-of-pocket expenses in health insurance choice. We also find that allowing MediSave payment for both premiums and out-of-pocket expenses (e.g. putting them in the same mental account) enhances individual welfare and reduces adverse selection.

University access has significantly expanded in OECD countries, and further growth figures prominently in political agendas. We study possible consequences of historical and future expansions in a stochastic, general equilibrium Roy model where tertiary educational attainment is determined by cognitive ability and socioeconomic disadvantage. In our analysis, individual productivity depends not only on education but also directly on cognitive ability. The expansion of university access in the U.K. that started in the 1960s provides an ideal case study to draw lessons for the future. We find that this expansion led to the selection into college of progressively less talented students from advantaged backgrounds. Appropriate counterfactual policies existed that would have achieved the dual goal of increasing college graduates’ cognitive ability while improving tertiary education opportunities for the disadvantaged.

We use population data on capital income and wealth holdings for Norway to measure asset positions and wealth returns before individuals marry and after the household is formed. These data allow us to establish a number of novel facts. First, individuals sort on personal wealth rather than parental wealth. Second, people match also on their personal returns to wealth and assortative mating on returns is as strong as that on wealth. Third, post-marriage returns on family wealth reflect in equal part the pre-marriage returns of the two spouses. However, for households at the top of the wealth distribution at marriage, family wealth is largely managed by the spouse with the highest potential to grow it, providing a microfoundation for the scale dependence in wealth returns documented in several empirical papers. Fourth, marriage lowers the degree of wealth inequality as well as the heterogeneity in returns relative to the counterfactual case of no marriages. We use a simple framework to illustrate how the inequality-attenuating role of marriage is affected by assortative mating on wealth and returns and by wealth management task allocation between spouses.

We examine the welfare-based opportunity cost of foreign exchange (FX) intervention when both covered interest rate parity (CIP) and uncovered interest rate parity (UIP) deviations are present. We consider a small open economy that receives international capital flows through constrained international financial intermediaries. Deviations from CIP come from limited arbitrage or through a convenience yield, while UIP deviations are also affected by global risk. We show that the sign of CIP and UIP deviations may differ for safe haven countries. We find that FX reserves may provide a net benefit, rather than a cost, when international intermediaries value the safe-haven properties of a currency more than domestic households. We show that this has been the case for the Swiss franc and the Japanese Yen. We examine the optimal policy of a constrained central bank planner in this context.

This paper investigates the importance of the age composition for pandemic policy design. To do so, it introduces an economic framework with age heterogeneity, individual choice, and incomplete information, emphasizing the value of testing. Calibrating the model to the US Covid-19 pandemic reveals an 80% reduction in the death toll due to voluntary actions and the lockdown implemented in the US. The optimal lockdown, however, is more stringent than what was implemented. Moreover, the social planner follows an asymmetric approach by locking down the young relatively more than the old. We highlight the role of testing in reducing deaths, lowering economic costs, and allowing for a less restrictive lockdown. A social planner would choose a faster ramp-up in testing capacity relative to what occurred in the US. We use the framework to provide insights into pandemics caused by different viruses (including the Spanish flu), and underline the influence of economic conditions on optimal policies.

Motivated by a secular increase in the concentration of the U.S. banking industry, I develop a new macroeconomic model with oligopolistic financial intermediaries and heterogeneous firms. Market power allows banks to price discriminate and charge firm-specific markups, exerting greater market power over productive and more financially constrained firms. This dampens capital accumulation and amplifies the effects of macroeconomic shocks. During a crisis, banks exploit the higher share of financially constrained firms to extract higher markups, inducing a larger decline in real activity. When a large bank fails, the remaining banks use their increased market power to restrict credit supply, worsening and prolonging the downturn.

This paper studies a multi-product monopolist facing a privately informed consumer with additive and type-increasing valuations. Separate monopoly pricing is robustly optimal with respect to the type distribution if and only if the marginal rate of substitution between each pair of goods is monotone. This result is obtained by extending the conventional Myersonian approach.

We study the impact of large, successful manufacturing plants on other local producers in China, focusing on “Million-Rouble Plants” built in the 1950s during a brief alliance with the U.S.S.R. The ephemeral geopolitical situation and the locations of allied and enemy airbases provide exogenous variation in plant siting. We find a boom-and-bust pattern: Counties hosting these plants were 80% more productive than control counties in 1982 but 20% less productive by 2010. This decline reflects the performance of local establishments, which exhibit low productivity, limited innovation, and high markup. Specialization hindered spillovers, preventing the emergence of new clusters and local entrepreneurship.

Racial covenants in housing deeds were widely used in the United States during the early 20th century to segregate neighborhoods. In 1948, the Supreme Court decision in Shelley v. Kraemer made racial covenants unenforceable in court, stopping short of prohibiting them entirely. We surmise that even after losing their judicial enforceability, such covenants could have shaped segregation if they served as a focal point for coordination on an initial equilibrium in neighborhood formation, a context characterized by investment durability and path dependency. To test this hypothesis, we assemble novel parcel-level data on racial covenants and develop a quasi-experimental design that exploits delays between covenant execution and housing construction to isolate exposure to enforceable covenants at the time neighborhoods were built. Covenant enforceability indeed affected early-stage neighborhood formation in terms of housing characteristics, public infrastructure placement, and the composition of initial residents. These early differences proved durable: Enforceable covenants account for 6–24% of the observed neighborhood racial segregation from 1980 to 2020 and 3.1–4.4% of housing price differentials in the 21st century. We conclude that by coordinating beliefs and decisions during neighborhood formation, the law generated spatial inequality that has long outlived racial covenants themselves.