Knowledge that Transforms

A single worker allocates her time among different projects which are progressively assigned. When the worker works on too many projects at the same time, the output rate decreases and completion time increases according to a law which we derive. We call this phenomenon “task juggling” and argue that it is pervasive in the workplace. We show that task juggling is a strategic substitute of worker effort. We then present a model where task juggling is the result of lobbying by clients, or coworkers, each seeking to get the worker to apply effort to his project ahead of the others’.

Procurement contracts are often renegotiated because of changes that are required after their execution. Using highway paving contracts we show that renegotiation imposes significant adaptation costs. Reduced form regressions suggest that bidders respond strategically to contractual incompleteness and that adaptation costs are an important determinant of their bids. A structural empirical model compares adaptation costs to bidder markups and shows that adaptation costs account for 7.5–14 percent of the winning bid. Markups from private information and market power, the focus of much of the auctions literature, are much smaller by comparison. Implications for government procurement are discussed.

We develop a framework where mismatch between vacancies and job seekers across sectors translates into higher unemployment by lowering the aggregate job-finding rate. We use this framework to measure the contribution of mismatch to the recent rise in US unemployment by exploiting two sources of cross-sectional data on vacancies, JOLTS and HWOL. Our calculations indicate that mismatch, across industries and three-digit occupations, explains at most one-third of the total observed increase in the unemployment rate. Occupational mismatch has become especially more severe for college graduates, and in the West of the United States. Geographical mismatch unemployment plays no apparent role.

Are teachers' impacts on students' test scores (value-added) a good measure of their quality? One reason this question has sparked debate is disagreement about whether value-added (VA) measures provide unbiased estimates of teachers' causal impacts on student achievement. We test for bias in VA using previously unobserved parent characteristics and a quasi-experimental design based on changes in teaching staff. Using school district and tax records for more than one million children, we find that VA models which control for a student's prior test scores provide unbiased forecasts of teachers' impacts on student achievement.

We employ data that match the population of Danish workers to the universe of private-sector Danish firms, with product-level trade flows by origin- and destination-countries. We document new stylized facts about offshoring and instrument for offshoring and exporting. Within job spells, offshoring increases (decreases) the high-skilled ( low-skilled) wage; exporting increases the wages of all skill-types; the net wage-effect of trade varies substantially within the same skill-type; conditional on skill, the wage-effect of offshoring varies across task characteristics. We estimate the overall effects of offshoring on workers' present and future income streams by constructing pre- offshoring-shock worker-cohorts and tracking them over time.

This paper models growth via on-the-job learning when firms and workers are heterogeneous. It is an overlapping generations model in which young agents match with the old. More efficient assignments lead to faster long-run growth, more inequality, and less turnover in the distribution of human capital. Constant-growth paths are characterized for general functional forms and then, for the Cobb-Douglas case, the transition dynamics are solved analytically when the skill of the young is log-normally distributed and the initial human capital of the old generation is also log-normal. Growth and inequality move together on the transition to the balanced growth path.

This paper explores the nature of fluctuations in world bulk shipping by quantifying the impact of time to build and demand uncertainty on investment and prices. We examine the impact of both construction lags and their lengthening in periods of high investment activity, by constructing a dynamic model of ship entry and exit. A rich dataset of secondhand ship sales allows for a new estimation strategy: resale prices provide direct information on value functions and allow their nonparametric estimation. We find that moving from time-varying to constant to no time to build reduces prices, while significantly increasing both the level and volatility of investment.

Resale price maintenance (RPM), slotting fees, loyalty rebates, and other related vertical practices can allow an incumbent manufacturer to transfer profits to retailers. If these retailers were to accommodate entry, upstream competition could lead to lower industry profits and the breakdown of these profit transfers. Thus, in equilibrium, retailers can internalize the effect of accommodating entry on the incumbent’s profits. Consequently, if entry requires downstream accommodation, entry can be deterred. We discuss policy implications of this aspect of vertical contracting practices.

This article develops a Bayesian framework for estimating multivariate treatment effect models in the presence of sample selection. The methodology is applied to a banking study that evaluates the effectiveness of lender of last resort (LOLR) policies and their ability to resuscitate the financial system. This paper employs a novel bank-level dataset from the Reconstruction Finance Corporation, and jointly models a bank's decision to apply for a loan, the LOLR's decision to approve the loan, and the bank's performance a few years after the disbursements. This framework offers practical estimation tools to unveil new answers to important regulatory questions.

A carbon tax is a promising tool for discouraging the greenhouse gas emissions that cause climate change. In principle, a well-designed tax could reduce the risk of climate change, minimize the cost of emissions reductions, encourage innovation in low-carbon technologies, and raise new public revenue. But designing a real-world carbon tax poses significant challenges. We analyze those challenges from a public finance perspective, emphasizing three tax policy design issues: setting the tax rate, collecting the tax, and using the resulting revenue. The benefits of a carbon tax will depend on how policymakers address those issues.