Knowledge that Transforms

Abstract We introduce markup equilibrium—an extension of Walrasian equilibrium in which consumers pay a fixed percentage markup over producer prices. In quasilinear markets, markup equilibria exist despite nonconvexities. They are resource-feasible and envy-free, incur no budget deficit, and require little more communication and computation than ordinary Walrasian equilibrium. The associated markup mechanism is asymptotically incentive-compatible. We also introduce a Bound-Form First Welfare Theorem, which states that for any feasible allocation, the welfare loss compared to the first-best is bounded, using any price vector, by the sum of the resulting (i) budget surplus and (ii) rationing losses suffered by the participants. Using producer prices, this bound implies that any markup equilibrium with a small markup and few unallocated goods is nearly efficient.

Abstract I propose a model of skill-replacing routine-biased technological change (SR-RBTC). In this model, technology substitutes for the use of skill in routine tasks, in contrast to standard RBTC models, which assume that technology replaces the workers themselves. The SR-RBTC model explains three key trends that are inconsistent with standard RBTC models: (1) why specifically middle wages declined even though workers in routine occupations are dispersed across the entire bottom half of the wage distribution, (2) why middle wages stopped declining while technological change continued, and (3) why there is no substantial decline in the average wage of workers in routine occupations. I derive two new testable predictions from the model: a decrease in the return to skill and a decrease in skill level in routine occupations. I use an interactive fixed-effects model to confirm both predictions. Since SR-RBTC violates the ignorability assumption required by standard decomposition methods, I introduce a “skewness decomposition” to show that SR-RBTC is the main driver of bottom-half inequality trends.

Abstract We study the role of public risk-sharing in markets where firms face substantial cost uncertainty, focusing on public reinsurance in health insurance. We develop a model where insurers internalize cost uncertainty through risk charges that raise effective marginal costs and create a role for reinsurance. Public reinsurance lowers both expected costs and cost volatility, particularly for smaller insurers, reducing prices and enhancing competition. Using an event study of staggered state-level reinsurance programs, we show that public reinsurance leads insurers to lower prices and private reinsurance purchases, benefiting financially constrained insurers the most. Structural estimates indicate that risk charges account for a substantial share of the premium-cost wedge and highlight public reinsurance’s comparative advantage over premium subsidies by providing risk protection and enhancing competition. Our results underscore the importance of accounting for firms’ risk exposure in policy design and provide a general framework for understanding public risk-sharing policies.

Abstract We consider an oligopoly model in which each firm chooses not only its price but also its advertising strategy regarding how much, and what, product information to provide. To highlight firms’ strategic incentives, we impose no structural restrictions on feasible advertising content, so that each firm can disclose or conceal any information. We obtain a comprehensive characterization of the equilibrium advertising strategy and provide some sufficient conditions for the existence of symmetric pure-price equilibria. We show that intense competition induces firms to provide accurate product information; firms usually obfuscate consumers’ relatively low or high values; and requiring firms to provide more product information can reduce social surplus and also be harmful to consumers.

Abstract We study the labour market effects of permanent 30%–64% reductions on unemployment insurance benefits available in seven states. Leveraging linked firm-establishment data, we find that establishments based on reform states experience employment increases that are 0.8%–1.3% larger than those of the same firm’s establishments in other states. Using a similar multi-state firm design, starting salaries are 1.2%–5.5% lower in reform states and posted salaries for the same job fall by 3.2%–3.5%. The negative co-movement of employment and wages after the reform suggests a labour supply shock and mitigates against confounding changes in labour demand driving the results. Our findings are consistent with workers lowering their reservation wages as outside options fall, and employers take advantage of this by offering lower wages and increasing employment.

Abstract Business dynamism—the process of firm entry, growth and exit—lies at the heart of modern endogenous growth models. While productivity differences have traditionally been seen as the main driving forces of business dynamism, a growing body of evidence suggests that customer acquisition is at least as important. In light of this evidence, we propose a novel endogenous growth model in which innovating firms must first acquire customers to sell their products. Estimating our model with aggregate and firm-level data, we find that expansions of firms’ customer bases (market sizes) boost their incentives to innovate and shift resources towards high-growth businesses (“gazelles”). Combined, these effects explain over 40% of aggregate growth and substantially change predictions about the efficacy of growth policies. Finally, we document support for key model predictions using firm-level micro-data.

Abstract What are the effects of supply-side climate policies in the oil market? We use global company-level data to estimate the impact of 84 reforms of production taxes between 2000 and 2019 on oil production, exploration, and discoveries. We find that higher taxes primarily reduce companies’ exploration expenditures and oil discoveries, and also reduce short-term production of unconventional oil. We then quantify the implications for the oil market using a short- and medium-term dynamic model extending until the end of the century. Imposing a global climate royalty surcharge of 20 percentage points on oil producers reduces average annual emissions from oil by 5–7% in the first 5 years, and 9–20% in the medium term. If only OECD countries adopt this policy, 47–73% of the total emission reductions would be offset by increased production in non-OECD countries in the medium term.

Abstract Manager pay has increased considerably since 1980, and so has inequality in manager pay. Over the same period, there has been a sharp rise in market power. We start from the premise that the role of managers is to increase firm productivity. When markets are imperfectly competitive, productivity not only helps firm grow in size, productivity also affects market power. We model how imperfect competition in product markets affects manager pay, and break down the contributions of firm size and market power to compensation. We find that market power, on average, accounts for 45.2% of total manager pay. Notably, there is substantial variation across managers. Top managers are disproportionately employed by firms with market power, and they benefit from it: in 2019, 80.3% of top manager pay is attributable to market power. Our main conclusion is that rise of market power explains half of the increase in average manager pay, and nearly all of the increase in manager pay inequality.

Abstract For many technologies and behaviours, an agent’s benefit from adopting depends on his contacts adopting, and the benefit to his contacts of adopting depends on their contacts adopting. This paper examines how the architecture of these connections shapes the success or failure of the diffusion of innovations. We start with a standard model of diffusion with the key addition that some agents can coordinate their decisions. This captures the idea that people often talk and make decisions together with friends or family to adopt technologies. We show that insularity of connections, that is, the extent to which agents tend to concentrate their connections to a narrow set of other agents, determines contagion. However, whether insularity helps or hinders depends on the technology being diffused. For technologies that are valuable even without many contacts adopting, we find insular connections hinder adoption, but for technologies that are valuable only when many contacts adopt, insular connections facilitate adoption.

Abstract This article combines personnel records of the U.S. government with census data to study how exposure to greater female representation at work can persistently reduce intergenerational gender gaps in labour market outcomes. Exploiting city-by-department variation in the sudden expansion of female employment during World War I, we find that daughters of civil servants exposed to female co-workers are more likely to work later in life. This intergenerational effect operates through exposed fathers and extends beyond the public sector, reducing the earnings gap by 12%. Consistent with a broader shift in attitudes towards working women, exposure to female co-workers also made male civil servants more likely to marry working women. We show that cities exposed to larger increases in female federal workers saw persistently higher female labour force participation in both the public and the private sector. Increasing gender representation within the public sector can thus have broader labour market implications.