Knowledge that Transforms

In this article, we provide direct evidence on the behaviour of markups in the retail sector across space and time. Markups are measured using gross margins. We consider three levels of aggregation: the retail sector as a whole, the firm, and the product level. We find that: (1) markups are relatively stable over time and mildly procyclical; (2) there is a large regional dispersion in markups; (3) there is a positive cross-sectional correlation between local income and local markups; and (4) differences in markups across regions result from differences in the assortment of goods sold in different regions, not from deviations from uniform pricing. We propose a simple model consistent with these facts.

A screening instrument is costly if it is socially wasteful and productive otherwise. A principal screens an agent with multidimensional private information and quasilinear preferences that are additively separable across two components: a one-dimensional productive component and a multidimensional costly component. Can the principal improve upon simple one-dimensional mechanisms by also using the costly instruments? We show that if the agent has preferences between the two components that are positively correlated in a suitably defined sense, then simply screening the productive component is optimal. The result holds for general type and allocation spaces, and allows for nonlinear and interdependent valuations. We discuss applications to monopoly pricing, bundling, and labour market screening.

This article studies the impact of the arbitrator selection process on consumer outcomes. Using data from consumer arbitration cases in the securities industry over the past two decades, where we observe detailed information on case characteristics, the randomly generated list of potential arbitrators presented to both parties, the selected arbitrator, and case outcomes, we establish several motivating facts. These facts suggest that firms hold an informational advantage over consumers in selecting arbitrators, resulting in industry-friendly arbitration outcomes. We then develop and calibrate a quantitative model of arbitrator selection in which firms hold an informational advantage in selecting arbitrators. Arbitrators, who are compensated only if chosen, compete with each other to be selected. The model allows us to decompose the firms’ advantage into two components: the advantage of choosing pro-industry arbitrators from a given pool and the equilibrium pro-industry tilt in the arbitration pool that arises because of arbitrator competition. Selecting arbitrators without the input of firms and consumers would increase consumer awards by $60,000 on average relative to the current system. Forty percent of this effect arises because the pool of arbitrators skews pro-industry due to competition. Even an informed consumer cannot avoid this pro-industry equilibrium effect. Counterfactuals suggest that redesigning the arbitrator selection mechanism for the benefit of consumers hinges on whether consumers are informed. Policies intended to benefit consumers, such as increasing arbitrator compensation or giving parties more choice, would benefit informed consumers but hurt the uninformed.

This article assesses the long-run effects of the 1989 Canada-U.S. Free Trade Agreement on the Canadian labour market using matched longitudinal administrative data for the years 1984–2004. We simultaneously examine the labour market effects of increased export expansion and import competition, generally finding adverse effects of Canadian tariff cuts and favourable effects of U.S. cuts, though both effects are small. Workers initially employed in industries that experienced larger Canadian tariff concessions exhibit a heightened probability of layoffs at large firms, but little impact on long-run cumulative earnings. Lower earnings and years worked at the initial employer are offset by gains in other manufacturing industries, construction, and services. Canadian workers quickly transitioned out of industries facing import competition, with the bilateral nature of the FTA providing import-competing workers employment options in alternative manufacturing industries benefiting from larger U.S. tariff cuts.

We develop a dynamic contracting theory of asset- and cash flow-based financing that demonstrates how firm, intermediary, and capital market characteristics jointly shape firms’ financing constraints. A firm with imperfect access to equity financing covers financing needs through costly sources: an intermediary and retained cash. The firm’s financing capacity is endogenously determined by either the liquidation value of assets (asset-based) or the intermediary’s going-concern valuation of the firm’s cash flows (cash flow-based). The optimal contract is implemented with defaultable debt—specifically unsecured credit lines and senior-secured debt—and features risk-sharing via bankruptcy. When the firm does well, it repays its debt in full. When it does poorly, distress resolution mirrors U.S. bankruptcy procedures (Chapters 7 and 11). Secured and unsecured debt are complements because risk-sharing via unsecured debt increases secured debt capacity. Debt and equity are dynamic complements because future access to equity financing increases current debt capacity.

Quality provision is often low in many developing markets, and firms commonly lack a reputation for quality. This article examines this issue both theoretically and empirically in the context of retail watermelon markets in China. I first demonstrate the existence of significant asymmetric information on quality between sellers and buyers, as well as the absence of a quality premium at baseline. To explain this, I develop a theoretical model that highlights the role of consumer beliefs and costly signalling in influencing sellers’ reputation incentives. I then conduct an experiment by randomly introducing two signalling technologies into different markets: a cheap sticker label and a more expensive laser-cut label. Consistent with the theoretical predictions, the laser label induces sellers to offer higher quality, resulting in increased sales and profits, while the sticker label fails to achieve the same effect. Using the experimental variation, I estimate an empirical model of consumer learning to uncover the underlying evolution of beliefs. The results show that pessimistic beliefs under the sticker label can hinder reputation building, whereas the laser label enhances consumer learning and strengthens sellers’ reputation incentives.

Bridges are critical but sparse links in land transport networks. I exploit quasi-experimental variation in bridge construction over major rivers in the U.S. to measure the causal effects of land transport infrastructure. Bridges are more often built upstream than downstream of tributary confluences—where smaller rivers join larger rivers—generating local differences in connectivity. Local connectivity advantages have negative effects on per capita income. In contrast, more substantial changes in connectivity arising from the opening of major bridges increase per capita economic activity. A narrative explanation that can reconcile both results is that land transport infrastructure creates productivity advantages that drive economic growth, structural transformation, and urbanization over large spatial scales, but local sorting within the cities that form around early transport routes then reverses this gradient over smaller spatial scales.

The information banks produce drives their lending decisions and macroeconomic outcomes, but this information is inherently difficult to analyse because it is private. We construct a novel measure of bank information quality from confidential regulatory data that include banks’ private risk assessments for US corporate loans. Information quality improves as local economic conditions deteriorate, particularly for new loans, large loans, and loans with higher expected losses. Information quality also declines during periods of rapid local house price appreciation. Our results provide empirical support for theories of countercyclical information production in credit markets.

Complementarities between partners’ characteristics are often held responsible for the patterns of assortative mating observed in marriage markets along different dimensions, such as race and education. However, when the marriage market is segmented into racially and educationally homogeneous clusters, people naturally have more match opportunities with their likes. In this paper, we build an empirically tractable dynamic matching model with endogenous separation and remarriage. In every period, agents participate in a competitive matching game with transferable utility, where mating strategies depend on both the expected match gains and search frictions in the form of meeting costs. We leverage panel data on the duration of both non-cohabiting and cohabiting relationships to jointly estimate both determinants of assortative mating with a nationally representative sample of the U.S. population. We show that, in the absence of search frictions, the share of matches between people of the same race (education) would decrease from 88.2% (49.2%) to 55.5% (40.8%), as opposed to 53.3% (33.5%) if singles were randomly matched. As a result, search frictions explain nearly all the racial homogamy observed in the data, but only approximately half of the observed educational homogamy, with the other half attributed to match complementarities. In a counterfactual exercise, we show that minority groups experiencing an unfavourable gender ratio when marriage markets are segmented, such as Hispanic men and Black women, would benefit from access to a broader and more diverse pool of partners.

We develop a test for instrument strength based on the bias of two-stage least squares (2SLS) that (1) generalizes Stock and Yogo’s and Sanderson and Windmeijer’s tests to be robust to heteroskedasticity and autocorrelation, and (2) extends Montiel Olea and Pflueger’s robust test for models with a single endogenous regressor to multiple endogenous regressors. Our test can be based either on an absolute bias criterion or on the 2SLS bias relative to a worst-case benchmark. We also develop extensions to test whether weak instruments cause bias in individual 2SLS coefficients. In simulations, our test controls size and is powerful, and we provide efficient code packages for its practical implementation. We demonstrate our testing procedures in the context of the estimation of state-dependent fiscal multipliers, following recent leading estimates.