Knowledge that Transforms

We measure the welfare distortions from endogenous quality choice in imperfectly competitive markets. For US cable television markets between 1997–2006, prices are 33 percent to 74 percent higher and qualities 23 percent to 55 percent higher than socially optimal. Such quality overprovision contradicts classic results in the literature and our analysis shows that it results from the presence of competition from high-end satellite TV providers: without the competitive pressure from satellite companies, cable TV monopolists would instead engage in quality degradation. For welfare, quality overprovision implies cable customers would prefer smaller, lower-quality cable bundles at a lower price, amounting to a twofold increase in consumer surplus for the average consumer. (JEL L13, L15, L82)

We analyze test design and certification standards when an uninformed seller has the option to generate and disclose costly information regarding asset quality. We characterize equilibria by a minimum principle: the test and disclosure policy are chosen to minimize the asset’s value conditional on nondisclosure. Thus, when sellers choose the information provided, simple pass/fail certification tests are likely to dominate the market. A social planner could raise informational and allocative efficiency, and lower deadweight testing costs, by raising the certification standard. Monopolist certifiers also satisfy the minimum principle but set a higher standard and reduce testing rates to maximize revenue. (JEL D42, D83, L12, L15)

Schools worldwide distribute information to parents about their children’s academic performance. Do frictions prevent parents, particularly low-income parents, from accessing this information to make decisions? A field experiment in Malawi shows that, at baseline, parents’ beliefs about their children’s academic performance are often inaccurate. Providing parents with clear, digestible performance information causes them to update their beliefs and adjust their investments: they increase the school enrollment of their higher-performing children, decrease the enrollment of lower-performing children, and choose educational inputs that are more closely matched to their children’s academic level. Heterogeneity analysis suggests information frictions are worse among the poor. (JEL C93, D83, I21, I24, J13, O15)

We study the effect of physician workforce diversity on the demand for preventive care among African American men. In an experiment in Oakland, California, we randomize black men to black or non-black male medical doctors. We use a two-stage design, measuring decisions before (pre-consultation) and after (post-consultation) meeting their assigned doctor. Subjects select a similar number of preventives in the pre-consultation stage, but are much more likely to select every preventive service, particularly invasive services, once meeting with a racially concordant doctor. Our findings suggest black doctors could reduce the black-white male gap in cardiovascular mortality by 19 percent. (JEL I12, I14, C93)

We argue that an influential neo-Fisherian analysis of the effects of low interest rates depends on using perfect-foresight equilibrium analysis under circumstances where it is not plausible for people to hold expectations of that kind. We propose an explicit cognitive process by which agents may form their expectations of future endogenous variables. Perfect foresight is justified by our analysis as a reasonable approximation in some cases, but in the case of a commitment to maintain a low nominal interest rate for a long time, our reflective equilibrium implies neither neo-Fisherian conclusions nor implausibly strong predicted effects of forward guidance. (JEL D84, E12, E31, E43, E52)

We estimate the causal effects of acute fine particulate matter exposure on mortality, health care use, and medical costs among the US elderly using Medicare data. We instrument for air pollution using changes in local wind direction and develop a new approach that uses machine learning to estimate the life-years lost due to pollution exposure. Finally, we characterize treatment effect heterogeneity using both life expectancy and generic machine learning inference. Both approaches find that mortality effects are concentrated in about 25 percent of the elderly population.

We introduce a new experimental paradigm to evaluate employer preferences, called incentivized resume rating (IRR). Employers evaluate resumes they know to be hypothetical in order to be matched with real job seekers, preserving incentives while avoiding the deception necessary in audit studies. We deploy IRR with employers recruiting college seniors from a prestigious school, randomizing human capital characteristics and demographics of hypothetical candidates. We measure both employer preferences for candidates and employer beliefs about the likelihood that candidates will accept job offers, avoiding a typical confound in audit studies. We discuss the costs, benefits, and future applications of this new methodology. (JEL D83, I26, J23, J24, M51)

We study empirically how past exposure to conflict in origin countries makes migrants more violence-prone in their host country, focusing on asylum seekers in Switzerland. We exploit a novel and unique dataset on all crimes reported in Switzerland by the nationalities of perpetrators and of victims over 2009–2016. Our baseline result is that cohorts exposed to civil conflict/mass killing during childhood are 35 percent more prone to violent crime than the average cohort. This effect is particularly strong for early childhood exposure and is mostly confined to co-nationals, consistent with inter-group hostility persisting over time. We exploit cross-region heterogeneity in public policies within Switzerland to document which integration policies are best able to mitigate the detrimental effect of past conflict exposure on violent criminality. We find that offering labor market access to asylum seekers eliminates two-thirds of the effect. (JEL D74, F22, K42, Z18)

The National Banking Acts (NBAs) of 1863–1864 established rules governing the amounts and locations of interbank deposits, thereby reshaping the bank networks. Using unique data on bank balance sheets and detailed interbank deposits in 1862 and 1867 in Pennsylvania, we study how the NBAs changed the network structure and quantify the effect on financial stability in an interbank network model. We find that the NBAs induced a concentration of interbank deposits at both the city and bank levels, creating systemically important banks. Although the concentration facilitated diversification, contagion would have become more likely when financial center banks faced large shocks. (JEL E44, G01, G21, G28, L14, N21)

We study how goods- and labor-market frictions affect aggregate labor productivity in China. Combining unique data with a general equilibrium model of internal and international trade, and migration across regions and sectors, we quantify the magnitude and consequences of trade and migration costs. The costs were high in 2000, but declined afterward. The decline accounts for 36 percent of the aggregate labor productivity growth between 2000 and 2005. Reductions in internal trade and migration costs are more important than reductions in external trade costs. Despite the decline, migration costs are still high and potential gains from further reform are large. (JEL E24, F16, J24, P23, P25, R12, R23)