Correcting agglomeration economies: How air pollution matters

This paper aims to correct standard measures of agglomeration economies to account for air pollution. This paper examines the impact of nitrogen oxide (NO_X) a pollutant mainly released by transportation on worker productivity. Literature on agglomeration economies highlights the positive role of employment density on productivity, without accounting for the negative impacts of local pollutants. First, standard estimates of agglomeration economies for the 304 French employment areas are in line with the literature. Then, we introduce the variable (NO_X) emissions and, once pollution is accounted for, the estimated direct impact of agglomeration externalities on productivity are lower by more than 13 per cent.     

Strangers in our midst: the usefulness of exploring polycentricity

The existence and persistence of cities provide prima facie evidence of agglomeration economies, but do little to inform our understanding of the specific nature of forces that induce the concentration of economic activity, nor the spatial scale at which they occur. Though the theoretical literature on conceptualizes these forces without specific geographic scale, the empirical literature largely treats them as working mainly at the metropolitan level. We argue that agglomeration may work at different spatial scales. There is now extensive evidence that metropolitan areas are polycentric, with a significant portion of employment clustered in employment centers outside the CBD. This provides basic evidence of net agglomeration benefits at the sub-metropolitan level. We explore theories of agglomeration and consider how they may explain the presence, location, characteristics, and growth of employment centers. We illustrate the usefulness of exploring polycentricity with a case study of the Los Angeles region. Our understanding of agglomeration economies can be enriched by investigating the nature of employment centers and the forces that produce and sustain them.     

A monopolistic competition model of spatial agglomeration with variable density

In this paper, we combine the monopolistic competition model of Fujita (1988) with the variable density model by Tabuchi (1986), Liu (1988) and Grimaud (1989), and develop a monopolistic competition model of spatial agglomeration with variable density. We compare the results of the present paper with those of previous work, and show that some previous results cannot be carried over to our generalized model with variable density.This research has been supported by NSF grant SES 85-02886, which is gratefully acknowledged     

Rank-size distribution of urban employment in labour market areas

This paper examines the rank-size distribution of employment in cities considering the designation of unified labour market areas (LMAs). The empirical application refers to Greece and the dataset includes population and employment at the municipal and local commune levels as well as LMAs originating from commuting patterns between communes. It is found that the employment rank-size distribution based on municipalities substantially overestimates the size of smaller peripheral town areas, where labour agglomerations typically take place at finer spatial scales, and underestimates agglomerations around larger urban areas. The use of LMAs as an alternative spatial unit of analysis entails a less even geographical distribution of workers, particularly when adopting a 10% commuting threshold. Moreover, a threshold regression is used to facilitate the distinction between urban and rural areas, specifying the LMA size beyond which substantial urbanisation effects arise and signifying that about 80% of the total employment corresponds to urban employment. The findings can have important implications for the formulation and evaluation of policies to manage labour agglomeration economies in metropolitan and peripheral urban and rural areas for the sustainable and equitable growth of a country.     

Urban spatial structure,agglomeration economies,and economic growth in Barcelona: An intra‐metropolitan perspective*

This paper presents an intra‐metropolitan approach to analyse the impact of urban spatial structure on local economic growth. Focusing on the Barcelona metropolitan region (BMR) between 1986 and 2001, we estimate a municipal employment growth model in which dynamic agglomeration economies related to urban spatial structure are considered using distance to employment centres, to assess metropolitan effects, and distance‐weighted variables, to measure neighbourhood effects. The results obtained show the existence of neighbourhood specialization economies and metropolitan urbanization‐localization economies fostering local growth. All of this leads to the paper's main conclusion: urban spatial structure is important for economic growth in an intra‐metropolitan context.     

Self‐employment and local economic performance: Evidence from US counties*

This study explores the relationship between self‐employment and income growth, employment growth, and change in poverty in metro and non‐metro areas in the United States using county‐level panel data. We investigate the impact of the relative size of the self‐employment sector measured by the share of non‐farm proprietorships (NFPs) in total full and part‐time employment on three key economic performance indicators. We first estimate an income growth model to analyse the effects of self‐employment on income growth. Then we investigate the independent effects of self‐employment on employment growth and changes in family poverty rates. Our results indicate that higher self‐employment rates are associated with statistically significant increases over time in income and employment growth, and reductions in poverty rates in non‐metro counties. We find similar effects on metro county income and employment, but not on poverty dynamics.     

Walled cities and urban density in China

We analyse a sample of nearly 300 prefectural-level cities in China, among which about half historically had city walls. We document that cities that had walls in late imperial China have higher population and employment density today, despite that their walls have long gone. Using data from various sources, we test whether a historically walled city's higher density can be explained by a historical urban core, a different industry composition, a different local geography, a compact urban shape, or more valuable rural land in surrounding areas. We find that historically walled cities still have higher density after taking into account all of these factors, which we interpret as evidence of economic persistence.     

Agglomeration externalities and localized employment growth: the performance of industrial sites in Amsterdam

This paper addresses the question to what extent the performance of industrial sites is affected by their local economic structure and accessibility. For this aim, we test for the existence of statistically significant relationships between agglomeration externalities (specialization, diversity, and competition), accessibilty measures and the employment growth of a particular industry on a particular site. We use data on employment growth of site-industries on 68 formal industrial sites in the municipality of Amsterdam between 1998 and 2006. We show that at the site-industry level, specialization hampers growth. Furthermore, we find that industrial sites that are easily accessible from the highway grow relatively fast, as well as sites located in the Amsterdam harbour area.     

Agglomeration and firm‐level productivity: A Bayesian spatial approach

This paper estimates the impact of industrial agglomeration on firm‐level productivity in Chinese manufacturing sectors. To account for spatial autocorrelation across regions, we formulate a hierarchical spatial model and use a Bayesian instrumental‐variable approach. We find that agglomeration of the same industry (i.e., localization) has a productivity‐boosting effect, but agglomeration of urban population (i.e., urbanization) has no such effect. In addition, the localization effect increases with the educational levels of employees and the share of intermediate inputs in gross output. These results may suggest that agglomeration externalities occur through knowledge spillovers and input sharing among firms producing similar manufactures.     

分职业视角下南京市外来工就业空间分布研究——兼论其与城市就业空间的关联

以南京市主城区展开实证,基于"分职业"(商业服务业和生产运输设备操作业)视角,从"就业集聚分区"和"就业中心体系"两方面,探讨外来务工人员就业空间的分布特征,并进一步通过空间拟合解析其与城市就业空间的关联。结果显示:(1)商业服务业外来工就业集聚区大量集中于主城中南部核心区域,生产运输设备操作外来工就业集聚区大量集中于主城北部边缘区域,二者叠加致使外来工就业总体呈现出明显的"核心放射+半环带"的空间分布格局。(2)商业服务业外来工呈单中心就业体系,生产运输设备操作外来工无就业中心,两种职业人口共同集聚致使外来工总体呈现出一"主"一"次"、分具"单一"和"综合"特征的"双中心"结构。(3)商业服务业人员外来工就业集聚区呈现出较好的融合特性,而生产运输设备操作外来工就业集聚区则呈现出吸引和互斥的多重特征,致使外来工总体与城市就业空间呈现出融合与隔离并存的双重特性。(4)外来工分职业和城市分行业就业中心呈现出更多的相似性,商业服务业外来工就业与城市服务业还呈现出明显的分子力作用关系,但叠加之后,两者总体上呈现出了截然相异的空间体系,外来工就业在西北沿江地区形成了独立于城市就业结构的"非依附性质"的另类中心。     

The spatial distribution of inventor networks

Inventor networking has become both more feasible with improved telecommunication and more important as it usually produces research of higher quality. Despite overwhelming evidence on the benefits of collaboration, patent data from 1994 to 2001 in Sweden demonstrate that inventor networks are not very common. Moreover, the spatial distribution of inventor networks is not uniform. It appears that agglomeration measured both as employment density and as industry diversity, plays a role in explaining networking. Our results indicate that inventor networks are more likely to exist in densely populated areas with a diversified industry. Market size has a negative impact on networking in that we can observe that inventor networks are less common in large metropolitan areas, ceteris paribus. Hence, it supports the proposition that networking can act as a substitute to agglomeration. Our results also suggest that researchers in dense areas will not only collaborate more; they will also collaborate over longer distance.     

Agglomeration, productivity, and spatial spillovers across Chinese cities

This paper investigates the causal relationship between, and the determinants of, urban labor productivity and industrial agglomeration across Chinese cities. We extend the Ciccone and Hall (Am Econ Rev 86(1):54–70, 1996) production density model by distinguishing between the size of the industrial sector and the density of the urban economy in order to examine the effects of industry agglomeration and congestion on urban productivity. We also account for the endogeneity of industrial agglomeration and propose a simultaneous equation model to estimate the determinants of urban productivity and agglomeration. A spatial econometric analysis across 617 Chinese cities in year 2005 shows that the spatial concentration of industrial production is an important cause of higher productivity in large industrial cities and cities in neighboring regions, where higher productivity resulting from concentrated industrial production then leads to further agglomeration in these cities. Controlling for the size of the industrial sector, employment density has a negative effect on urban productivity. We conclude by briefly discussing potential policy implications of the empirical findings.     

Determinants of journeys to work in central London, 1954–93

In this paper we analyze a unique data set compiled by London Transport since 1953, concerning the number of people working in the London CBD. We consider whether the marked changes over time in employment are attributable to changes in government policy, industrial structure, macroeconomic changes, transport costs or agglomeration economies. Using cointegration methods we conclude that macroeconomic developments are quantitatively the most important factor, although transport costs have significant effects. Government decentralization policy appears to have had little effect, although our results are consistent with the presence of agglomeration economies.     

Rates of urbanisation and the resiliency of air and water quality

Global human population and urban development are increasing at unprecedented rates and creating tremendous stress on local, regional, and global air and water quality. However, little is known about how urban areas vary in their capacity to address effectively air and water quality impacts associated to urban development. There exists a need to better understanding the factors that mediate the interactions between urbanisation and variations of environmental quality. By synthesizing literatures on the relationship between urban development and air and water quality, we assess the amount of scholarship for each of these cities, characterize population growth rates in one hundred of the largest global cities, and link growth trends to changes in air and water quality. Our results suggest that, while there is a growing literature linking urbanisation and environmental quality, some regions of the globe are better represented than others, and that these trends are consistent with our characterization of population growth rates. In addition, the comparison between population growth rates and air and water quality suggest that multiple factors affect the environmental quality, and that approaching rates of urbanisation through the lens of ‘resiliency’ can be an effective integrative concept for studying the capacity of urban areas to respond to rapid rates of change. Based on these results we offer a framework for systematically assessing changes in air and water quality in megacities.     

BEYOND ETHNIC ENCLAVES? EXPLORING THE SPATIAL DISTRIBUTION OF LATINO‐OWNED EMPLOYER FIRMS IN TWO U.S. IMMIGRATION GATEWAYS

The Latino population in the United States has increased dramatically during the past several decades. However, Latino‐owned businesses have been understudied. Even less is known about these firms’ spatial distribution. Built on an interdisciplinary literature on industrial locations and ethnic economies, this study examines how the development of ethnic minority–owned businesses is contingent on the local neighborhood as both a work site and habitat. Using a confidential national survey of ethnic minority–owned businesses in the United States, this study compares the spatial distribution of Latino‐owned employer firms in the Miami and Atlanta metropolitan areas. Consistent with previous research, results from this study strongly reinforce the importance of a connection between ethnic population concentration and emergence of ethnic businesses. A concentration of local businesses and co‐locating with other businesses, regardless of ethnicity, are very important as well. Such agglomeration effects seem particularly important for new immigration destinations like Atlanta where a favorable entrepreneurial environment is still being developed for ethnic minority businesses. However, the positive effects from co‐locating with local businesses are not linear. A threshold effect and small count preferences are detected in the two study areas.     

Locating Software,Video Game,and Editing Electronics Firms: Using Microgeographic Data to Study Barcelona

This paper analyzes location patterns of software, video game, and editing electronics firms (hereafter SVE) in the Metropolitan Area of Barcelona using microgeographic data. These industries are mainly attracted by agglomeration economies look to benefit from skilled labor and spillover effects, and tend to cluster in large metropolitan areas. However, less is known about their detailed location patterns inside these areas. We contribute to the empirical literature by identifying how SVE firms are concentrated in some core areas of the metropolitan area. Our empirical application includes using the Nearest Neighbor Index (NNI) and M-functions, as well as local spatial autocorrelation indicators.     

Agricultural productivity in densely populated areas

The impact of population density on agricultural productivity in the New York and Philadelphia metropolitan areas is assessed using an aggregate production function. The concept of agglomeration economies is used to explain the relationships among population density, proximity to metropolitan areas and agricultural productivity. Regression results indicate that the technical efficiency of farming operations is disadvantaged in more densely populated areas.     

县域乡村建设规划编制要点思考——以歙县县域乡村建设规划为例

县域乡村建设规划作为全新的规划编制类型,侧重于发挥中观层面的规划统筹与建设指引作用,对推动乡村规划编制体系改革具有重要意义.对于乡村空间聚集模式的研究(镇村体系、公共服务配置等)、对指导乡村建设的关键性技术的研究以及乡村重大建设项目落地问题研究,既是县域乡村建设规划的编制重点,也是其编制技术难点.在空间聚集模式研究方面,歙县县域乡村建设规划尝试从地形、人口密度、客观交通条件约束、人口的迁移愿景等方面出发,强调对乡村空间集聚的趋势生判断,并依托镇村分级和功能分类指导乡村各类设施配置.指导乡村建设的关键性技术研究既是县域乡村建设规划重要的技术创新内容,也是提升规划实施效力的关键性环节,其编制深度应达到下位规划编制的前期研究的深度,并辅以一系列的编制指引和技术导则,以增强其解释能力.此外,为了促进乡村地区“多规合一”,支持乡村重大建设项目落地实施,歙县县域乡村建设规划还在“倡导建立统一的综合规划管理信息系统”、编制部门指引强化规划解读、创新地方规划管理政策和管理机制、编制重大建设项目库等方面做出了一定技术探索.     

Effects of dynamic and spatial externalities on local growth: Evidence from Brazil

This paper analyses the impact of economic externalities on the local growth emphasizing the industrial, geographic, and temporal scope of agglomeration economies. Thus, we estimated a spatial dynamic panel model using GMM associated with the use of data at different levels of sectoral aggregation. Estimation takes into account the endogeneity of agglomeration economies. Our database consists of 558 Brazilian regions for 1995–2015. The main results suggest that while externalities act in a local dimension they also have a regional scale. These externalities are determined by their temporal trajectory. The effects of agglomeration economies on local growth are sensitive to the choice of sectoral aggregation. Local growth exhibits positive specialization effects and negative diversity effects. However, greater industrial diversity of neighbouring regions has a positive impact on local growth.     

Worker and firm heterogeneity,agglomeration, and wages in Brazil

This paper analyses the influence of agglomeration and spatial sorting on wages in Brazilian cities. The empirical strategy is based on a two-step estimation. The first step estimates a wage equation with the observed characteristics of workers and firms and location effects. The second step decomposes the location effects into employment density and fixed effects of firm and worker. We estimate an urban wage premium for a developing country with the simultaneous inclusion of worker and firm fixed effects, instrumental variables, and nighttime lights. We find agglomeration effects of 4.3–5.7%, which are larger than those obtained for developed countries.