Understanding the city size wage gap

In 2000, wages of full time full year workers were more than 30 percent higher in metropolitan areas of over 1.5 million people than rural areas. The monotonic relationship between wages and city size is robust to controls for age, schooling and labor market experience. In this paper, we decompose the city size wage gap into various components. We propose an on-the-job search model that incorporates latent ability, search frictions, firm-worker match quality, human capital accumulation and endogenous migration between large, medium and small cities. Counterfactual simulations of the model indicate that variation in returns to experience and differences in wage intercepts across location type are the most important mechanisms contributing to the overall city size wage premium. Steeper returns to experience in larger cities is more important for college graduates while differences in wage intercepts is more important for high school graduates. Sorting on unobserved ability within education group and differences in labor market search frictions and distributions of firm-worker match quality contribute little or slightly negatively to observed city size wage premia in both samples

The skyscraper revolution: global economic development and land savings

Tall buildings are central to facilitating sustainable urbanization and growth in cities worldwide. We estimate average elasticities of city population and built area to aggregate city building heights of 0.12 and -0.17, respectively, indicating that the largest global cities in developing economies would be at least one-third smaller on average without their tall buildings. Land saved from urban development by post-1975 tall building construction is over 80% covered in vegetation. To isolate the effects of technology-induced reductions in the cost of height from correlated demand shocks, we use interactions between static demand factors and the geography of bedrock as instruments for observed 1975-2015 tall building construction in 12,877 cities worldwide, a triple difference identification strategy. Quantification using a canonical urban model suggests that the technology to build tall generates a potential global welfare gain of 4.8%, of which only about one-quarter has been realized. Estimated welfare gains from relaxing existing height constraints are 5.9%in the developed world and 3.1% in developing economies

Does investment in national highways help or hurt hinterland city growth?

We investigate the effects of the recently constructed Chinese national highway system on local economic outcomes. On average, roads that improve access to local markets have small or negative effects on prefecture economic activity and population. However, these averages mask a distinct pattern of winners and losers. With better regional highways, economic output and population increase in regional primates at the expense of hinterland prefectures. Highways also affect patterns of specialization. With better regional highways, regional primates specialize more in manufacturing and services, while peripheral areas lose manufacturing but gain in agriculture. Better access to international ports promotes greater population, GDP, and private sector wages on average, effects that are probably larger in hinterland than primate prefectures. An important policy implication is that investing in local transport infrastructure to promote growth of hinterland prefectures has the opposite effect, causing them to specialize more in agriculture and lose economic activity

When models fall short: Evidence from Chinese road infrastructure investments

Despite limits to data quality and to the possibilities for recovering causal relationships between infrastructure investment, urbanisation and economic growth, quantitative models may prove to be weak substitutes for direct empirical evidence. For evidence based policymaking, research technique matters

Transport Infrastructure and the Decentralization of Cities in the People's Republic of China

It is widely believed that transport infrastructure has important impacts on the development of cities. Until recently, however, there has been little systematic evidence with which to evaluate claims about the effects of transport infrastructure on the development of cities and regions. In this paper, we describe the evolution of transport infrastructure in the People's Republic of China and how it relates to the evolution of location patterns of population and production in Chinese cities and their surrounding regions. We summarize empirical evidence from Baum-Snow et al. (2017) on the causal effects of various types of transport infrastructure on the decentralization of cities in the People's Republic of China. Finally, we put our results in the context of the existing literature on the effects of infrastructure on productivity and the allocation of resources across locations

Roads, railroads and decentralization of Chinese cities

We investigate how configurations of urban railroads and highways influenced urban form in Chinese cities since 1990. Each radial highway displaces about 4 percent of central city population to surrounding regions and ring roads displace about an additional 20 percent, with stronger effects in the richer coastal and central regions. Each radial railroad reduces central city industrial GDP by about 20 percent, with ring roads displacing an additional 50 percent. Similar estimates for the locations of manufacturing jobs and residential location of manufacturing workers is evidence that radial highways decentralize service sector activity, radial railroads decentralize industrial activity and ring roads decentralize both. Historical transportation infrastructure provides identifying variation in more recent measures of infrastructure

Regional-Based Mitigation to Reduce Wildlife–Vehicle Collisions

Vehicular collisions with large ungulates pose serious challenges for managing and conserving large ungulates throughout the world. Despite the global frequency, mitigation efforts are mostly limited to localized hotspots and not effective on broad scales. Our goal was to determine whether dynamic, regional attributes could inform broader focus for mitigation efforts. We applied a spatiotemporal dynamic model to examine the regional influences on white-tailed deer (Odocoileus virginianus)–vehicle collisions (DVCs) throughout the Midwest United States from traffic, abundance of deer, and composition and configuration of the landscape during 2000–2011. The regions included eco-zones representing landscape dominated by shelter-forage habitats with ubiquitous and abundant distribution of deer (i.e., forest-agriculture matrix), landscape dominated by agriculture with sparse refugia (i.e., agriculture), and landscape dominated by forests with seasonal migration for deer (i.e., northern forest). We found little fluctuation in the factors affecting collisions through time but substantial differences among regions. In the forest-agriculture matrix eco-zone, fragmentation of the landscape was the most important predictor of collisions. In the agriculture eco-zone, traffic and abundance of deer best predicted collisions. In the northern forest eco-zone, the predictors of collisions were variable and likely related to winter severity and deer migration. This research provides new justification for broadening the focus of current mitigation measures to regional extents. In regions dominated by forest and agriculture, new policies that reduce habitat fragmentation should be the primary focus for reducing collisions. Reducing abundance of ungulates will have the most direct effect in regions dominated by agriculture. Finally, a variety of seasonal and local mitigation measures will be most effective in northern forests where large ungulates migrate

The Mechanism Design Approach to Student Assignment

The mechanism design approach to student assignment involves the theoretical, empirical, and experimental study of systems used to allocate students into schools around the world. Recent practical experience designing systems for student assignment has raised new theoretical questions for the theory of matching and assignment. This article reviews some of this recent literature, highlighting how issues from the field motivated theoretical developments and emphasizing how the dialogue may be a road map for other areas of applied mechanism design. Finally, it concludes with some open questions.National Science Foundation (U.S.