Do intellectual property (IP) rights on existing technologies hinder subsequent innovation? Using newly-collected data on the sequencing of the human genome by the public Human Genome Project and the private firm Celera, this paper estimates the impact of Celera's gene-level IP on subsequent scientific research and product development. Genes initially sequenced by Celera were held with IP for up to two years, but moved into the public domain once re-sequenced by the public effort. Across a range of empirical specifications, I find evidence that Celera's IP led to reductions in subsequent scientific research and product development on the order of 20 to 30 percent. Taken together, these results suggest that Celera's short-term IP had persistent negative effects on subsequent innovation relative to a counterfactual of Celera genes having always been in the public domain.

Evidence from both psychology and economics indicates that individuals give statements that appear to overestimate their ability compared to that of others. We test three theories that predict such relative overconfidence. The first theory argues that overconfidence can be generated by Bayesian updating from a common prior and truthful statements if individuals do not know their true type. The second theory suggests that self-image concerns asymmetrically affect the choice to receive new information about one's abilities, and this asymmetry can produce overconfidence. The third theory is that overconfidence is induced by the desire to send positive signals to others about one's own skill; this suggests either a bias in judgement, strategic lying, or both. We formulate this theory precisely. Using a large data set of relative ability judgements about two cognitive tests, we reject the restrictions imposed by the Bayesian model and also reject a key prediction of the self-image models that individuals with optimistic beliefs will be less likely to search for further information about their skill because this information might shatter their self-image. We provide evidence that personality traits strongly affect relative ability judgements in a pattern that is consistent with the third theory of social signalling. Our results together suggest that overconfidence in statements is more likely to be induced by social concerns than by either of the other two factors.

A large and growing share of world trade travels by air. We model exporters' choice between fast, expensive air cargo and slow, cheap ocean cargo, which depends on the price elasticity of demand and the value that consumers attach to fast delivery. We use US imports data that provide rich variation in the premium paid for air shipping and in time lags for ocean transit to extract consumers' valuation of time. We estimate that each day in transit is equivalent to an advalorem tariff of 0.6 to 2.1 percent. The most time-sensitive trade flows involve parts and components trade. (JEL F13, F14, L93)

We model retail-price recommendations (RPRs) as a communication device in vertical supply relations with private manufacturer information on production costs and consumer demand. With static trade, RPRs are irrelevant, and the equilibrium outcome is inefficient. With repeated trade, RPRs can become part of a relational contract, communicating private information from manufacturer to retailer that is indispensable for maximizing joint surplus. We show that this contract is self-enforcing if the retailer's profit is independent of production costs and punishment strategies are chosen appropriately. The predictions of our analysis are consistent with the available empirical evidence. (JEL D21, D24, L11, L14, L22, L60, L81)

A long line of research investigates whether the retail prices of electricity and natural gas send proper signals about scarcity in order to induce efficient consumption. Historically, regulated utilities have not designed tariffs that set marginal prices equal to marginal costs. Currently, some jurisdictions are opening the retail sectors to competition via “retail choice.” These new regimes replace imperfect regulation with imperfect competition as the process by which retail tariffs are formed. We discuss the challenges in evaluating the efficiency of tariffs and present evidence of how pricing has changed in markets with retail choice.

Sacrifice is widely believed to enhance cooperation in churches, communes, gangs, clans, military units, and many other groups. We find that sacrifice can also work in the lab, apart from special ideologies, identities, or interactions. Our subjects play a modified VCM game—one in which they can voluntarily join groups that provide reduced rates of return on private investment. This leads to both endogenous sorting (because free-riders tend to reject the reduced-rate option) and substitution (because reduced private productivity favours increased club involvement). Seemingly unproductive costs thus serve to screen out free-riders, attract conditional cooperators, boost club production, and increase member welfare. The sacrifice mechanism is simple and particularly useful where monitoring difficulties impede punishment, exclusion, fees, and other more standard solutions.

We provide a set of comparable estimates for the rates of inflow to and outflow from unemployment using publicly available data for fourteen OECD economies. Using a novel decomposition that allows for deviations of unemployment from its flow steady state, we find that fluctuations in both inflow and outflow rates contribute substantially to unemployment variation within countries. Anglo-Saxon economies exhibit approximately a 15:85 inflow-outflow split to unemployment variation, while continental European and Nordic countries display closer to a 45:55 split. In all economies, increases in inflows lead increases in unemployment, whereas outflows lag a ramp-up in unemployment.

An individual who takes an HIV test can be informed about their own status and risk. Similarly, when friends, family or neighbors learn of a person's HIV status, they may update their beliefs about HIV infection among people they know. Using an experiment conducted in rural Malawi which randomly assigned incentives to learn HIV results, we find that as people in the community learn their HIV results, individuals revise their beliefs downward about deaths attributable to HIV/AIDS. We find corresponding behavioral responses with a significant decrease in condom use and no significant increase in multiple partnerships among those who are HIV-negative.

One in five Zambian children lives with an HIV/AIDS-infected adult. We estimate the effect that the availability of adult antiretroviral therapy (ART) has on the health of such children. Using a triple difference specification, we find that adult access to ART resulted in increased weight-for-age and decreased incidence of stunting among children younger than 60 months who resided with an infected father or other infected adult in an intact household. Because the increased availability of adult ART in sub-Saharan Africa has multigenerational effects, cost-effectiveness estimates restricted to direct recipients understate the economic benefit of the treatment.

The control function approach is a convenient method of estimation in simultaneous equation systems. This requires that the system can be expressed in triangular form with variables satisfying a conditional mean independence restriction. Linear simultaneous models with additive errors can always be expressed in this form. However, in nonlinear nonadditive simultaneous systems, conditional independence requires a strong additional restriction known as control function separability. We argue that nonadditive models are a key characteristic of simultaneous models of economic behavior with unobserved heterogeneity. We review alternative “system” approaches and document the biases that occur when the control function approach is used inappropriately.