Knowledge that Transforms

We introduce a model where social norms of voting participation are strategically chosen by competing political parties and determine voters’ turnout. Social norms must be enforced through costly peer monitoring and punishment. When the cost of enforcement of social norms is low, the larger party is always advantaged. Otherwise, in the spirit of Olson (1965), the smaller party may be advantaged. Our model shares features of the ethical voter model and it delivers novel and empirically relevant comparative statics results.

Quantity vouchers are used in redistributive programs to shield participants from price variation and alter their consumption patterns. However, because participants are insensitive to prices, vendors of program goods are incentivized to price discriminate between program and non-program customers. I study these trade-offs in the context of a reform to reduce price discrimination in the Supplemental Nutrition Program for Women, Infants, and Children (WIC), which provides a quantity voucher for nutritious foods to low-income mothers and children. The reform caused vendors to drop out, reducing program take-up. In addition, smaller vendors increased prices charged to non-WIC shoppers by 6.4 percent.

We embed a field experiment in a nationwide recruitment drive for a new health care position in Zambia to test whether career benefits attract talent at the expense of prosocial motivation. In line with common wisdom, offering career opportunities attracts less prosocial applicants. However, the trade-off exists only at low levels of talent; the marginal applicants in treatment are more talented and equally prosocial. These are hired, and perform better at every step of the causal chain: they provide more inputs, increase facility utilization, and improve health outcomes including a 25 percent decrease in child malnutrition.

How do geographically concentrated income shocks influence the long-run spatial distribution of poverty within a city? We examine the impact on housing prices of a cholera epidemic in one neighborhood of nineteenth century London. Ten years after the epidemic, housing prices are significantly lower just inside the catchment area of the water pump that transmitted the disease. Moreover, differences in housing prices persist over the following 160 years. We make sense of these patterns by building a model of a rental market with frictions in which poor tenants exert a negative externality on their neighbors. This showcases how a locally concentrated income shock can persistently change the tenant composition of a block.

Tariffs are generally assumed to depend on the product, not the identity of the importer. However, special economic zones are a common, economically important policy used worldwide to lower tariffs on selected goods for selected manufacturers. I show this is motivated by policymakers’ desire to discriminate across buyers when a tax is intended to raise prices for sellers, through a mechanism distinct from existing theories of optimal taxation. Using a new dataset compiled from public records and exogenous changes in imports of intermediate goods, I find the form, composition, and size of US zones are consistent with the theory.

This paper documents a large association between individuals’ time discounting in incentivized experiments and their positions in the real-life wealth distribution derived from Danish high-quality administrative data for a large sample of middle-aged individuals. The association is stable over time, exists through the wealth distribution and remains large after controlling for education, income profile, school grades, initial wealth, parental wealth, credit constraints, demographics, risk preferences, and additional behavioral parameters. Our results suggest that savings behavior is a driver of the observed association between patience and wealth inequality as predicted by standard savings theory.

Long-run growth in many models is the product of two terms: the effective number of researchers and their research productivity. We present evidence from various industries, products, and firms showing that research effort is rising substantially while research productivity is declining sharply. A good example is Moore’s Law. The number of researchers required today to achieve the famous doubling of computer chip density is more than 18 times larger than the number required in the early 1970s. More generally, everywhere we look we find that ideas, and the exponential growth they imply, are getting harder to find.

Soda taxes aim to reduce excessive sugar consumption. We assess who is most impacted by soda taxes. We estimate demand using micro longitudinal data covering on-the-go purchases, and exploit the panel dimension to estimate individual-specific preferences. We relate these preferences and counterfactual predictions to individual characteristics and show that soda taxes are relatively effective at targeting the sugar intake of the young, are less successful at targeting the intake of those with high total dietary sugar, and are unlikely to be strongly regressive especially if consumers benefit from averted internalities.

We propose a criterion of stability for two-sided markets with asymmetric information. A central idea is to formulate off-path beliefs conditional on counterfactual pairwise deviations and on-path beliefs in the absence of such deviations. A matching-belief configuration is stable if the matching is individually rational with respect to the system of on-path beliefs and is not blocked with respect to the system of off-path beliefs. The formulation provides a language for assessing matching outcomes with respect to their supporting beliefs and opens the door to further belief-based refinements. The main refinement analyzed in the paper requires the Bayesian consistency of on-path and off-path beliefs with prior beliefs. We define concepts of Bayesian efficiency, the rational expectations competitive equilibrium, and the core. Their contrast with pairwise stability manifests the role of information asymmetry in matching formation.

Does public cheap talk by a biased expert benefit voters? The answer depends on the nature of democratic institutions and the extent of communication possibilities. Expert endorsements induce office-seeking parties to serve the expert’s interests, hurting voters. Expert advocacy makes policies respond to information, helping voters. Together, policy advocacy and partisan endorsements are often better than either alone. Their interaction creates a delegation benefit that makes indirect democracy superior to direct democracy and office-seeking parties better than those motivated by public interest. But voter welfare is highest when an expert captured technocratic party competes against an uninformed populist one.