Knowledge that Transforms

We provide novel insights on the decentralization of optimal outcomes under monopolistic competition with nonseparable utility, variable demand elasticity, and endogenous firm heterogeneity. Relative to the unconstrained optimum, equilibrium firm selection is too weak, average firm size is too small, low-cost firms are too small, and high-cost firms are too large. The unconstrained optimum can be decentralized through differentiated production subsidies to producers financed through lump-sum taxes on entrants and consumers. When differentiated subsidies and transfers from entrants are not viable, the constrained optimum can be decentralized through a common production subsidy financed by a lump-sum tax on consumers.

Disparate commitments to reduce GHG emissions create demands for border carbon adjustments (BCAs) to prevent negative competitive effects and carbon leakage. BCAs that accomplish economic objectives and are administratively feasible, WTO-legal, and politically acceptable may be impossible. BCAs should be limited to a few basic energy-intensive and trade-exposed products and should be based on the lower of the carbon content of production in the importing country and actual carbon content, or perhaps “best available technology.” Whether the World Trade Organization (WTO) would condone BCAs is unclear. BCAs violating basic trade rules might qualify for a special exception.

I consider economically sustainable online postsecondary education, including massive open online courses (MOOCs). The analysis suggests that MOOCs will be financially sustainable substitutes for some non-selective postsecondary education, but there are substantial risks. The analysis suggests that MOOCs will be financially sustainable substitutes for only a small share of highly selective postsecondary education (HSPE) and are likely to collapse the economic model that allows HSPE institutions to invest in advanced education and research. I outline a non-MOOC model of online education that may allow HSPE institutions to sustain their distinctive activities and to reach a larger number of students.

We provide an illustration of how the design of labor market clearing mechanisms can affect incentives for human capital acquisition. Specifically, we extend the labor market matching model (with discrete transfers) of Kelso and Crawford (1982) to incorporate the possibility that agents may invest in human capital before matching. We show that in this setting, the worker-optimal stable matching mechanism incentivizes workers to make (nearly) efficient human capital investments. En route to our main result, we show that so long as the space of salaries is sufficiently rich, every stable outcome in the Kelso and Crawford (1982) setting is approximately efficient.

Insurers have the reputation of being bad payers who nitpick whenever an opportunity arises. However, this nitpicking activity has a positive impact on their auditing strategy since auditing may prove profitable when claims are not fraudulent. We show that reducing the indemnity payments of audited claims induces a lower fraud rate at equilibrium and that some degree of nitpicking is socially optimal when insurance fraud is a concern. Its remains optimal even if it induces adverse effects on policyholders' moral standards.

Has there been an increase in positive assortative mating? Does assortative mating contribute to household income inequality? Data from the United States Census Bureau suggests there has been a rise in assortative mating. Additionally, assortative mating affects household income inequality. In particular, if matching in 2005 between husbands and wives had been random, instead of the pattern observed in the data, then the Gini coefficient would have fallen from the observed 0.43 to 0.34, so that income inequality would be smaller. Thus, assortative mating is important for income inequality. The high level of married female labor-force participation in 2005 is important for this result.

We analyze whether midlevel managers in securitized finance were aware of a large-scale housing bubble and a looming crisis in 2004–2006 using their personal home transaction data. We find that the average person in our sample neither timed the market nor were cautious in their home transactions, and did not exhibit awareness of problems in overall housing markets. Certain groups of securitization agents were particularly aggressive in increasing their exposure to housing during this period, suggesting the need to expand the incentives-based view of the crisis to incorporate a role for beliefs.

We study the design of mechanisms satisfying a novel desideratum: privacy. This requires the mechanism not reveal 'much' about any agent's type to other agents. We propose the notion of joint differential privacy: a variant of differential privacy used in the privacy literature. We show by construction that mechanisms satisfying our desiderata exist when there are a large number of players, and any player's action affects any other's payoff by at most a small amount. Our results imply that in large economies, privacy concerns of agents can be accommodated at no additional 'cost' to standard incentive concerns.

Using the Panel Study of Income Dynamics, we provide evidence that to understand household decisions and evaluate policies designed to affect individual welfare, it is important to add an intertemporal dimension to the by-now standard static collective models of the household. Specifically, we document that the observed differences in labor supply by gender and marital status do not arise suddenly at the time of marriage, but rather emerge gradually over time. We then propose an intertemporal collective model that has the potential of explaining the observed patterns.

This paper analyzes the effects on voting behavior of information disseminated over the Internet. We address endogeneity in Internet availability by exploiting regional and technological peculiarities of the preexisting voice telephony network that hindered the roll-out of fixed-line infrastructure for high-speed Internet. We find negative effects of Internet availability on voter turnout, which we relate to a crowding-out of TV consumption and increased entertainment consumption. We find no evidence that the Internet systematically benefits specific parties, suggesting ideological self-segregation in online information consumption. Robustness tests, including placebo estimations from the pre-Internet period, support a causal interpretation of our results.