@techreport{GohlSchrauth2022,
  type      = {Working Paper},
  author    = {Gohl, Niklas and Schrauth, Philipp},
  title     = {Ticket to Paradise?},
  series = {CEPA Discussion Papers},
  journal   = {CEPA Discussion Papers},
  number    = {50},
  issn      = {2628-653X},
  doi       = {10.25932/publishup-55846},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-558466},
  pages     = {20},
  year      = {2022},
  abstract  = {This paper provides novel evidence on the impact of public transport subsidies on air pollution. We obtain causal estimates by leveraging a unique policy intervention in Germany that temporarily reduced nationwide prices for regional public transport to a monthly flat rate price of 9 Euros. Us-ing DiD estimation strategies on air pollutant data, we show that this intervention causally reduced a benchmark air pollution index by more than six percent. Our results illustrate that public transport subsidies - especially in the context of spatially constrained cities - offer a viable alterna-tive for policymakers and city planers to improve air quality, which has been shown to crucially affect health outcomes.},
  language  = {en}
}
@techreport{BorckSchrauth2019,
  type      = {Working Paper},
  author    = {Borck, Rainald and Schrauth, Philipp},
  title     = {Population density and urban air quality},
  series = {CEPA Discussion Papers},
  journal   = {CEPA Discussion Papers},
  number    = {8},
  issn      = {2628-653X},
  doi       = {10.25932/publishup-42771},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-427719},
  pages     = {53},
  year      = {2019},
  abstract  = {We use panel data from Germany to analyze the effect of population density on urban air pollution (nitrogen oxides, particulate matter and ozone). To address unobserved heterogeneity and omitted variables, we present long difference/fixed effects estimates and instrumental variables estimates, using historical population and soil quality as instruments. Our preferred estimates imply that a one-standard deviation increase in population density increases air pollution by 3-12\%.},
  language  = {en}
}
@techreport{BorckSchrauth2022,
  type      = {Working Paper},
  author    = {Borck, Rainald and Schrauth, Philipp},
  title     = {Urban pollution},
  series = {CEPA Discussion Papers},
  journal   = {CEPA Discussion Papers},
  number    = {60},
  issn      = {2628-653X},
  doi       = {10.25932/publishup-57204},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-572049},
  pages     = {48},
  year      = {2022},
  abstract  = {We use worldwide satellite data to analyse how population size and density affect urban pollution. We find that density significantly increases pollution exposure. Looking only at urban areas, we find that population size affects exposure more than density. Moreover, the effect is driven mostly by population commuting to core cities rather than the core city population itself. We analyse heterogeneity by geography and income levels. By and large, the influence of population on pollution is greatest in Asia and middle-income countries. A counterfactual simulation shows that PM2.5 exposure would fall by up to 36\% and NO2 exposure up to 53\% if within countries population size were equalized across all cities.},
  language  = {en}
}