At the Nexus of Observational and Experimental Research: Theory,Specification, and Analysis of Experiments with Heterogeneous Treatment Effects

Experimentalists are increasingly examining heterogeneous treatment effects, in which observed individual-level characteristics are hypothesized to moderate an experimental treatment effect. Such work places researchers at the nexus of experimental and observational approaches. In this paper, we discuss the theoretical and statistical issues that can arise in testing such hypotheses. We note that inclusion of an observed (as opposed to randomly-assigned) moderator introduces the possibility of confounds that are commonplace in observational data analysis but too-easily ignored in experimental data analysis. We simulate several different data generating processes that include heterogeneous treatment effects, and we discuss the implications of various statistical models. We aim to provide researchers who examine heterogeneous treatment effects with background and advice that enable them to identify where common issues may arise and to develop research designs and implement statistical tests that will mitigate them.     

The Impact of Prenatal Exposure to Power Plant Emissions on Birth Weight: Evidence from a Pennsylvania Power Plant Located Upwind of New Jersey

To examine the infant health impact of prenatal exposure to power plant emissions, we draw scientific evidence on the impacted region downwind of a large polluter, a coal‐fired power plant located on the border of two states and proven to be the sole contributor to the violation of air quality standards of the impacted region. Our results show that among all live singleton births that occurred during 1990 through 2006, those born to mothers living as far as 20 to 30 miles away downwind from the power plant (which is also an affluent region) during pregnancy are at greater risks of low birth weight (LBW) and very low birth weight (VLBW): the likelihoods of LBW and VLBW could increase approximately by 6.50 and 17.12 percent, respectively. In light of the continual efforts of The U.S. Environmental Protection Agency in reducing cross‐state air pollution caused by transboundary power plant emissions, our study is aimed at broadening the scope of cross‐border pollution impact analysis by taking into account adverse infant health effects of upwind polluters, which can impose disproportionate burdens of health risks on downwind states due to air pollutants transported by wind.     

The structure of foreign policy attitudes in transatlantic perspective: Comparing the United States,United Kingdom,France and Germany

While public opinion about foreign policy has been studied extensively in the United States, there is less systematic research of foreign policy opinions in other countries. Given that public opinion about international affairs affects who gets elected in democracies and then constrains the foreign policies available to leaders once elected, both comparative politics and international relations scholarship benefit from more systematic investigation of foreign policy attitudes outside the United States. Using new data, this article presents a common set of core constructs structuring both American and European attitudes about foreign policy. Surveys conducted in four countries (the United States, the United Kingdom, France and Germany) provide an expanded set of foreign policy‐related survey items that are analysed using exploratory structural equation modeling (ESEM). Measurement equivalence is specifically tested and a common four‐factor structure that fits the data in all four countries is found. Consequently, valid, direct comparisons of the foreign policy preferences of four world powers are made. In the process, the four‐factor model confirms and expands previous work on the structure of foreign policy attitudes. The article also demonstrates the capability of ESEM in testing the dimensionality and cross‐national equivalence of social science concepts.     

The End of Sprawl? Not so Fast

This article takes a careful look at the recent state of sprawl among America’s 178 largest metropolitan areas through the lens of four sets of questions: (a) Measured at the metropolitan level, is sprawl really declining? Is it declining everywhere, or just in selected metropolitan areas? (b) If sprawl is indeed declining, are more compact growth forms on the rise? (c) If sprawl is indeed declining, is it the result of antisprawl land use and development policies? (d) Which metropolitan-level land market, demographic, and economic factors are most associated with changes in sprawl? It concludes that sprawl is indeed declining when measured by average population densities, but that the decline has been much less widespread if measured in terms of population growth in core-area neighborhoods, changing density gradient intercept and slope estimates, and increased employment clustering. In terms of policy, it finds no evidence that local regulatory regimes or growth management programs have had any effect on sprawl, but finds that the consistent administration of local regulatory programs in ways that incentivize infill development and send consistent signals to developers does contribute to reduced sprawl.     

Temporary Loan Limits as a Natural Experiment in Federal Housing Administration Insurance

The Economic Stimulus Act of 2008 dramatically but temporarily increased the mortgage loan amount eligible for insurance through the Federal Housing Administration (FHA). We use the implementation and expiration of these loan limits as a source of exogenous variation in the availability of FHA insurance to measure the impact on the overall mortgage market and conventional lending. We find that the introduction of higher loan limits increased the number of loan originations, but that the expiration of those loan limits roughly 6 years later did not significantly decrease affected loan originations. The substitution between loan products and small net impact on the overall mortgage market when the ESA loan limits expired may be explained by the return of a stronger conventional lending industry than existed during the housing crisis.     

Intraparty Hostility: Social Identity,Subidentity, and the Hostile Media Effect in a Contested Primary

The hostile media effect (HME) has generally been tested in terms of in-groups and out-groups, with a “neutral” story in between. This ignores the nature of many social groups as comprising subgroups, often but not always sharing feelings of connectedness and purpose. In cases when bounded subgroups are at odds with one another, HME provides little guidance. A contested partisan primary provides such a case. This study takes identity centrality, candidate favorability, and perceived social network homogeneity as measures of partisanship and involvement, hypothesizing relationships between each and perceived bias against one’s candidate and party. Findings show that markers of candidate-focused social identity predict greater perceived bias against one’s candidate during the 2016 primary season, while party-focused identity fails to predict perceived bias against one’s party. This suggests that candidate support identity overrides plain partisanship during primaries, supporting concern that a heated primary might damage general election party unity. Subsequent postconvention findings suggest that the salience of candidate-focused identity fades, while homogeneity of one’s network regarding party support helps to make perceived hostility toward one’s party identity more salient. However, as campaigns become more candidate-centered, the contestation between nested candidate and party identities may grow fiercer.