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Empirical researchers interested in the causal effect of the endogenous regressor often use instrumental variables. When few valid instruments are available, they typically estimate restricted specifications that impose uniform per unit treatment effects, even when these effects are likely to vary. We show that in these cases, ordinary least squares and instrumental variables estimators identify different weighted averages of all per unit effects, so the traditional Hausman test is uninformative about endogeneity. We develop a new exogeneity test that works even when the true model cannot be estimated using IV methods as long as a single valid instrument is available. We revisit three recent empirical examples to demonstrate the practical value of our test. [ABSTRACT FROM AUTHOR]

We study the long-run effects of one of the most ambitious regional development programs in U.S. history: the Tennessee Valley Authority (TVA). Using as controls authorities that were proposed but never approved by Congress, we find that the TVA led to large gains in agricultural employment that were eventually reversed when the program’s subsidies ended. Gains in manufacturing employment, by contrast, continued to intensify well after federal transfers had lapsed—a pattern consistent with the presence of agglomeration economies in manufacturing. Because manufacturing paid higher wages than agriculture, this shift raised aggregate income in the TVA region for an extended period of time. Economists have long cautioned that the local gains created by place-based policies may be offset by losses elsewhere. We develop a structured approach to assessing the TVA’s aggregate consequences that is applicable to other place-based policies. In our model, the TVA affects the national economy both directly through infrastructure improvements and indirectly through agglomeration economies. The model’s estimates suggest that the TVA’s direct investments yielded a significant increase in national manufacturing productivity, with benefits exceeding the program’s costs. However, the program’s indirect effects appear to have been limited: agglomeration gains in the TVA region were offset by losses in the rest of the country. Spillovers in manufacturing appear to be the rare example of a localized market failure that cancels out in the aggregate. JEL Codes: R11, J20, N92, O40. [ABSTRACT FROM PUBLISHER]

We study the effect of disclosing information on peers' salaries on workers' job satisfaction and job search intentions. A randomly chosen subset of University of California employees was informed about a new website listing the pay of University employees. All employees were then surveyed about their job satisfaction and job search intentions. Workers with salaries below the median for their pay unit and occupation report lower pay and job satisfaction and a significant increase in the likelihood of looking for a new job. Above-median earners are unaffected. Differences in pay rank matter more than differences in pay levels. (JEL I23, J28, J31, J64) [ABSTRACT FROM AUTHOR]

We are the first to examine the effect of Superfund cleanups on infant health rather than focusing on proximity to a site. We study singleton births to mothers residing within 5km of a Superfund site between 1989--2003 in five large states. Our ''difference in differences'' approach compares birth outcomes before and after a site clean-up for mothers who live within 2,000 meters of the site and those who live between 2,000--5,000 meters of a site. We find that proximity to a Superfund site before cleanup is associated with a 20 to 25% increase in the risk of congenital anomalies. [ABSTRACT FROM AUTHOR]

Using box-office data for all movies released between 1982 and 2000, I quantify how much the consumption decisions of individuals depend on information they receive from their peers, when quality is ex ante uncertain. In the presence of social learning, we should see different box-office sales dynamics depending on whether opening weekend demand is higher or lower than expected. I use a unique feature of the movie industry to identify ex ante demand expectations: the number of screens dedicated to a movie in its opening weekend reflects the sales expectations held by profit-maximizing theatre owners. Several pieces of evidence are consistent with social learning. First, sales of movies with positive surprise and negative surprise in opening weekend demand diverge over time. If a movie has better than expected appeal and therefore experiences larger than expected sales in Week 1, consumers in Week 2 update upward their expectations of quality, further increasing Week 2 sales. Second, this divergence is small for movies for which consumers have strong priors and large for movies for which consumers have weak priors. Third, the effect of a surprise is stronger for audiences with large social networks. Finally, consumers do not respond to surprises in first-week sales that are orthogonal to movie quality, like weather shocks. Overall, social learning appears to be an important determinant of sales in the movie industry, accounting for 32% of sales for the typical movie with positive surprise. This implies the existence of a large “social multiplier” such that the elasticity of aggregate demand to movie quality is larger than the elasticity of individual demand. [ABSTRACT FROM PUBLISHER]

A pervasive problem in estimating the costs of pollution is that optimizing individuals may compensate for increases in pollution by reducing their exposure, resulting in estimates that understate the full welfare costs. To account for this issue, measurement error, and environmental confounding, we estimate the health effects of ozone using daily boat traffic at the port of Los Angeles as an instrumental variable for ozone. We estimate that ozone causes at least $44 million in annual costs in Los Angeles from respiratory related hospitalizations alone and that the cost of avoidance behavior is at least $11 million per year. [ABSTRACT FROM AUTHOR]

We estimate the effect of extreme weather on life expectancy in the United States. Using high-frequency data, we find that both extreme heat and cold result in immediate increases in mortality. The increase in mortality following extreme heat appears mostly driven by near-term displacement, while the increase in mortality following extreme cold is long lasting. We estimate that the number of annual deaths attributable to cold temperature is 0.8% of average annual deaths in our sample. The longevity gains associated with mobility from the Northeast to the Southwest account for 4% to 7% of the total gains in life expectancy experienced by the U.S. population over the past thirty years. [ABSTRACT FROM AUTHOR]

Critics argue that electronic voting is vulnerable to fraud. We test whether voting technology affected electoral outcomes in the 2000 and 2004 presidential elections. We find a positive correlation between use of electronic voting and George Bush vote share. The effect could have been large enough to influence the final results in some swing states. While this pattern would appear to be consistent with allegations of voting irregularities, a closer examination suggests this interpretation is unlikely. We find no evidence that electronic voting had a larger effect in swing states, or in states with a Republican secretary of state. We also find that electronic voting has a negative effect on turnout rates of Hispanics (who tend to favor Democrats). Electronic voting was more likely to be used in counties with a higher fraction of Hispanics; especially in swing states. [ABSTRACT FROM AUTHOR]

We estimate the effect of social capital on the ability of households to insure consumption after unexpected negative shocks. Many theoretical models argue that strong ties to extended family members and to one's community help protect families when an adult becomes ill or disabled. Using household-level longitudinal data on Indonesian families, we test whether consumption declines less after a negative health shock for those with many ties to their community and for those in a community with dense ties. We take advantage of a particularly rich set of measures of social capital including measures of civic participation; the existence of traditions of mutual cooperation; long-term relationships in the community and ethnic and linguistic diversity. We also examine the role of a large and prosperous extended family. We find little support for the hypothesis that social capital is the capital of the poor. [ABSTRACT FROM AUTHOR]