The long-run economic consequences of high-stakes examinations : evidence from transitory variation in pollution

Cognitive performance during high-stakes exams can be affected by random disturbances that, even if transitory, may have permanent consequences. We evaluate this hypothesis among Israeli students who took a series of matriculation exams between 2000 and 2002. Exploiting variation across the same student taking multiple exams, we find that transitory PM2.5 exposure is associated with a significant decline in student performance. We then examine these students in 2010 and find that PM2.5 exposure during exams is negatively associated with postsecondary educational attainment and earnings. The results highlight how reliance on noisy signals of student quality can lead to allocative inefficiency

Counting the cost of indoor air pollution

New research reveals the economic and health impacts of indoor air pollution. Sefi Roth and Edward Pinchbeck outline the significance of the findings and discuss how policymakers can devise effective and just policies to mitigate its adverse effects on society

Making the invisible visible: the impact of revealing indoor air pollution on behavior and welfare

Exposure to ambient air pollution has been shown to be detrimental to human health and productivity, and has motivated many policies to reduce such pollution. However, given that humans spend 90% of their time indoors, it is important to understand the degree of exposure to Indoor Air Pollution (IAP), and, if high, ways to reduce it. We design and implement a field experiment in London that monitors households’ IAP and then randomly reveals their IAP in real-time. At baseline, we find that IAP is worse than ambient air pollution when residents are at home and that for 38% of the time, IAP is above World Health Organization standards. Additionally, we observe a large household income-IAP gradient, larger than the income-ambient pollution gradient, highlighting large income disparities in IAP exposure. During our field experiment, we find that the randomized revelation reduces IAP by 17% (1.9 µg/m3 ) overall and 34% (5 µg/m3 ) during occupancy time. We show that the mechanism is households using more natural ventilation as a result of the feedback (i.e., opening up doors and windows). Finally, in terms of welfare, we find that: (i) households have a willingness to pay of £4.8 ($6) for every 1 µg/m3 reduction in indoor PM2.5; (ii) households have a higher willingness to pay for mitigation than for full information; (iii) households have a price elasticity of IAP monitor demand around -0.75; and (iv) a £1 subsidy for an IAP monitor or an air purifier infinite marginal value of public funds, i.e., a Pareto improvement

Dirty density: air quality and the density of American cities

We study whether urban density affects the exposure of city dwellers to ambient air pollution using satellite-derived measures of air quality for the contiguous United States. For identification, we rely on an instrumental variable strategy, which induces exogenous variation in density without affecting pollution directly. For this purpose, we use three variables measuring geological characteristics as instruments for density: earthquake risks, soil drainage capacity and the presence of aquifers. We find a positive and statistically significant pollution-density elasticity of 0.13. We also assess the health implications of our findings and find that doubling density in an average city increases annual mortality costs by as much as $630 per capita. Our results suggest that, despite the common claim that denser cities tend to be more environmentally friendly, air pollution exposure is higher in denser cities. This in turn highlights the possible trade-off between reducing global greenhouse gas emissions and preserving environmental quality within cities

Covid-19: cities get hit first, but do not necessarily get hit harder

Is there a link between population density and COVID-19 spread and severity in the United States? Felipe Carozzi, Sandro Provenzano and Sefi Roth (Centre for Economic Performance, LSE) found denser locations were more likely to have an early outbreak, but do not necessarily suffer more in the longer run

Crime is in the air: the contemporaneous relationship between air pollution and crime

Many empirical studies have examined the various determinants of crime. However, the link between crime and air pollution has been largely overlooked. In this paper we study whether exposure to ambient air pollution affects crime using daily administrative data for London in 2004-05. For identification, we estimate models with ward fixed effects and implement two instrumental variable strategies, using atmospheric inversions and wind direction as exogenous shocks to local pollution. We find that air pollution has a positive and statistically significant impact on overall crime and on several major crime categories, including those with economic motives. Importantly, the effect also occurs at pollution levels which are well below current regulatory standards and appears to be unevenly distributed across income groups. Our results suggest that reducing air pollution in urban areas may be an effective measure to reduce crime and that air pollution forecasts can be used to improve predictive policing

Air pollution and respiratory infectious diseases

Recent research suggests that short-term exposure to air pollution is associated with an elevated prevalence of respiratory infectious disease. In this paper, we examine the relationship between the air quality index and weekly cases of COVID-19 and influenza-like illnesses (ILI) in the United States. We address potential bias from omitted variables and measurement error with an instrumental variable approach using atmospheric temperature inversions. Unlike other recent studies, we find no relationship between air quality and either COVID-19 or ILI cases

Urban density and Covid-19

This paper estimates the link between population density and COVID-19 spread and severity in the contiguous United States. To overcome confounding factors, we use two Instrumental Variable (IV) strategies that exploit geological features and historical populations to induce exogenous variation in population density without affecting COVID-19 cases and deaths directly. We find that density has affected the timing of the outbreak, with denser locations more likely to have an early outbreak. However, we find no evidence that population density is positively associated with time-adjusted COVID-19 cases and deaths. Using data from Google, Facebook, the US Census and The County Health Rankings and Roadmaps program, we also investigate several possible mechanisms for our findings. We show that population density can affect the timing of outbreaks through higher connectedness of denser locations. Furthermore, we find that population density is positively associated with proxies for social distancing measures, access to healthcare and income, highlighting the importance of these mediating factors in containing the outbreak

Putting Low Emission Zones (LEZs) to the test: the effect of London’s LEZ on education

This paper evaluates the impact of London’s Low-Emission Zone (LEZ) on test scores among elementary school students in England. Utilising administrative data for the years 2005-2015, we employ a difference-in-differences approach to assess the LEZ’s effect on standardised Key Stage 2 results (age 1 1). Our analysis reveals a statistically and economically significant improvement of 0.09 standard deviations in test scores for students within the LEZ compared to those in other urban control areas. Importantly, we also find that the LEZ policy has larger positive effects in low-performing schools, demonstrating its potential to significantly reduce educational disparities