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1.
It has recently been suggested that cities and regions should focus upon attracting talented individuals as a means to develop. Such a suggestion implies two things: first that it is possible to meaningfully alter migration flows by way of local policy, and second that these flows have an effect on local growth (and not the reverse as has generally been admitted). In this paper, we begin to investigate the empirical foundations of such assertions by examining some structural determinants of graduate migration flows by comparing them, in a gravity model context, to flows of nongraduates. Our contention is that, if migration flows are structured by such factors, then policies aimed at modifying flows—and any research purporting to give such policy advice—must first take them into account. We show that migration flows are strongly dependent on basic gravity variables such as size and distance, but that these and other variables (such as income differences, presence of graduates and border effects) do not affect all flows equally. Furthermore, we show that certain factors that are assumed to be local (such as wage levels) in fact only operate at a provincial level. Thus policies implemented locally may have little or no effect if they are manipulating factors that operate at a different scale.  相似文献   

2.
This study assesses the overall spatial variations and neighbourhood‐level “hot spots” of low birth weight and preterm birth incidence within three public health units in Ontario, Canada. The analysis uses a stepwise approach of intra‐class correlation analysis, a spatial scan statistic, and multilevel spatial modeling. Results show that neighbourhood level variation accounts for only 2–3 percent of the total variation of adverse birth outcomes in the study area. However, strong spatial autocorrelation is observed at the neighbourhood level, and spatial clusters of relatively high adverse birth outcome rates exist in areas that are associated with environmental risks, including pollution sources and proximity to highways. Thus, although estimated neighbourhood impacts on adverse birth outcomes are small compared with those of individual‐level risks, local high potential environmental risk areas are identifiable. Environmental surveillance and spatial statistical analysis should be conducted regularly by local health authorities to identify and monitor the impact of environmental changes on health in general and on birth outcomes in particular. Specific community‐oriented health interventions may be required to reduce observed local health impacts.  相似文献   

3.
ABSTRACT Recent empirical work suggests that (i) incomes are converging through time, and (ii) income and pollution levels are linked. This paper weds these two literatures by examining the spatial and temporal distribution of pollution. After establishing that theoretical predictions about whether pollution will converge are critically linked to certain structural parameters, we explore pollution convergence using state‐level data on two important pollutants—nitrogen oxides and sulfur oxides—from 1929 to 1999. We find stronger evidence of converging emission rates during the federal pollution control years (1970–1999) than during the local control years (1929–1969). These results suggest that income convergence alone may not be sufficient to induce convergence of pollutant emissions.  相似文献   

4.
We increasingly understand the causes of population decline: these can be, among others, processes of deindustrialization, decreasing fertility or the succession of a city through the stages of urban life as the city matures. However, we are still insufficiently able to explain why differences still exist between cities within regions experiencing the same macro‐processes and between cities of the same “level of maturity”. This research addresses this intra‐regional differentiation in population development in the declining former mining region of Saarland (Germany). Quantitative and qualitative analysis reveals that the differentiation in current decline stems from (1) the differentiated population development trajectories of the past, with a massive population boom followed by an aged and declining population in the industrial municipalities; and (2) the spatial distribution of amenities over the region; and (3) the spatial distribution and accessibility of housing opportunities steering migration flows. The latter are not necessarily concentrated in those areas that are attractive. Rather, the distribution of these housing opportunities strictly follows the planning logic of the supra‐local institutional framework, with a concentration of housing within easy access of major transportation infrastructure and in larger centres. The case study thus reveals that the mechanisms behind this intraregional differentiation are much more complex than often portrayed in the urban development and decline debate.  相似文献   

5.
We examine the contribution to economic growth of entrepreneurial marketplace information within a regional endogenous growth framework. Entrepreneurs are posited to provide an input to economic growth through the information revealed by their successes and failures. We empirically identify this information source with the regional variation in establishment births and deaths. To account for the potential endogeneity caused by forward‐looking entrepreneurs, we utilize instruments based on historic mining activity. We find that the information spillover component of local establishment birth and death rates have significant positive effects on subsequent entrepreneurship and employment growth for U.S. counties and metropolitan areas.  相似文献   

6.
ABSTRACT Aviation noise is a harmful pollutant, which has yet to be studied in the environmental justice literature. This paper uses Tobit and logit multivariate regression analyses to analyze noise pollution exposure from a major commercial‐service airport. It addresses the issue of whether people moved to the aviation noise‐impacted areas or the noise encroached on the people, and controls for economic and political costs as well as the possibility of racial and ethnic prejudice. The results indicate that ethnicity is the primary cause of the disproportionate burden of aviation noise pollution borne by Hispanics in the area analyzed.  相似文献   

7.
Spatial Empirics for Economic Growth and Convergence   总被引:10,自引:0,他引:10  
This paper suggests some new empirical strategies for analyzing the evolution of regional income distributions over time and space. These approaches are based on extensions to the classical Markov transition matrices that allow for a more comprehensive analysis of the geographical dimensions of the transitional dynamics. This is achieved by integrating some recently developed local spatial statistics within a Markov framework. Insights to not only the frequency with which one economy may transition across different classes in the income distribution, but also how those transitions may or may not be spatially dependent are provided by these new measures. A number of indices are suggested as ways to characterize the space‐time dynamics and are illustrated in a case study of U. S. regional income dynamics over the 1929–1994 period.  相似文献   

8.
"An empirical test of the effects of exogenous shocks upon a region's population size is conducted in the framework of an equilibrium locational model. The model emphasizes the separation of endogenous from exogenous factors, a point omitted in most empirical studies of aggregate migration. Exogenous changes are manifested in the local relative cost of living and the local relative unemployment rate. Hypotheses are tested using a national sample of youth, in addition to census, data [for the United States]. Surprisingly, a simple measure of the size of shock to a regional economy has the greatest explanatory power compared to more sophisticated measures based on prior business cycles."  相似文献   

9.
The space–time autoregressive integrated moving average (STARIMA) model family provides useful tools for modeling space–time processes that exhibit stationarity (or near stationarity) in space and time. However, a more general method for routine use and efficient computation is needed to model the nonlinearities and nonstationarities of environmental space–time series. This article presents a hybrid framework combining machine learning and statistical methods to address this issue. It uses an artificial neural network (ANN) to extract global deterministic (nonlinear) space–time trends and a STARIMA model to extract local stochastic space–time variations in data. A four‐stage procedure is proposed for analyzing and modeling space–time series. The proposed framework and procedures are applied to forecast annual average temperature at 137 national meteorological stations in China. The results demonstrate that the hybrid framework achieves better forecasting accuracy than the STARIMA model alone. This finding suggests that the combination of machine learning and statistical methods provides a very powerful tool for analyzing and modeling space–time series of environmental data that have strong spatial nonlinear and nonstationary components.  相似文献   

10.
The spatial and temporal variability of nitrogen dioxide (NO2) concentrations and their relationships with meteorology was evaluated in the Toronto–Hamilton urban airshed. NO2 concentrations were highest in the early morning and late evening. Mean concentrations were highest in winter, although individual one-hour NO2 concentrations were found to be highest in summer. Wind direction was the strongest control on hourly NO2 concentration, and temperature and wind speed also had an effect. Our analysis of NO2 concentration variation by wind direction showed that areas downwind of major highways, urban centres and industry were exposed to higher pollutant concentrations. Seasonal patterns of NO2 concentration displayed significant spatial heterogeneity, in particular, in Toronto. Onshore winds sheltered coastal inhabitants from the full extent of NO2 exposure they would otherwise experience. Seasonal variations in meteorology and emissions mean that the degree of spatial variability in NO2 concentrations changes from season to season. This study will help to improve existing land-use regression-based NO2 prediction models by incorporating meteorological controls on NO2 distributions for health effect studies.  相似文献   

11.
On the role of amenities in models of migration and regional development   总被引:2,自引:0,他引:2  
"The role of location-specific amenities in human migration decisions, and subsequently regional development, is explored. A framework is developed which motivates a new assessment of existing alternative models of regional development, indicating the need for additional modeling efforts which focus upon amenities as critical elements in such analyses. The approach hinges upon the notion that amenity values are capitalized into wages, rents, or other local prices. This process of capitalization enables researchers to explore the implicit value that society places upon amenities, which can then be used in assessing future regional-development trends in a more comprehensive manner."  相似文献   

12.
In this article we analyse differences between capital‐ and labour‐intensive sectors with regard to the impact of workforce composition and labour mobility on plant performance. By the use of geo‐referenced longitudinal employer–employee data on a micro level, we analyse labour flows between plants within and between labour market regions. The analysis is carried out using weighted least squares (WLS) regression analysis combined with additional variance analysis (ANOVA). The results show that there are differences between the sectors with regard to both in‐house workforce composition and type of skill inflow. A high degree of related knowledge in the in‐house workforce has a strong positive effect on plant performance in the labour‐intensive sectors. The analysis of labour inflow indicates that knowledge in the capital‐intensive sectors is localized – only intra‐regional labour flows give rise to increased plant productivity. In the labour‐intensive sectors, the geographic and cognitive dimensions complement one another; similar knowledge needs to be non‐local in order to be beneficial to plant performance, and unrelated knowledge mainly contributes to plant productivity growth when it is local.  相似文献   

13.
Optimization models for the design of regional air quality control strategies have been developed under the assumption that the annual frequencies of the different meteorological conditions remain constant from year to year. This paper demonstrates empirically that this assumption is not correct, and that the solutions of such models lead either to violation of the annual air quality standard or to unnecessarily high costs for pollution abatement. A chance-constrained, geographically based approach is formulated to account for the interannual randomness of the meteorological conditions and for the locations of pollution sources and receptors and is applied with different approximation methods. The policy implications of the results in terms of optimal standard selection and implementation of the optimal chance-constrained pollution abatement plan through decentralized decision-making by individual pollution sources are assessed.  相似文献   

14.
The European Union (EU) constitutes a space that offers a wealth of opportunities for regional learning. This article addresses how the learning process takes place in an interregional project and how contextual factors affect the learning process. The work presented here draws upon theories on regional learning and the dissemination of management ideas, as well as taking agency and structure components into account. The internal project arenas are investigated in order to shed light on the learning process and how spatial relations play a critical role. A conclusion is that the learning process within EU financed projects will gain from developing the practice of reflection and space-sensitive dialogues. One challenge to be dealt with is the relationship between the metamessage of the project, and local variations and various gender narratives.  相似文献   

15.
One important extension of the IAD framework has been to the study of local public economies. These are multi‐organizational, multi‐level arrangements defined as the set of governmental jurisdictions, public and nonprofit agencies, and private firms that interact in various patterns to provide and produce public goods and services within a specific locality or region. Commonly, the localities or regions studied from this perspective have been U.S. metropolitan areas, often defined as a central city and its surrounding or adjoining county. Localities can be delineated, however, on various terms, and in the IAD framework, it is the geo‐physical nature of a locality that, in substantial part, drives the analysis. One of the strengths of the approach is its capacity to explain local variations in public organization as a function of the geo‐physical diversity of localities, while at the same time developing empirical generalizations and normative principles that apply across diverse regions. What, for example, might the organization and governance of a complex metropolitan area have in common with the organization and governance of a complex protected area, such as the greater Yellowstone eco‐region or the Adirondack Park? Construing both sorts of regions as local public economies can enhance our overall understanding of public organization at the same time that it permits a more nuanced understanding of diverse localities. Such work contributes to the ongoing IAD project of “understanding institutional diversity.”  相似文献   

16.
Alida Cantor 《对极》2017,49(5):1204-1222
California's state constitution prohibits the “wasteful” use of water; however, waste is subjective and context dependent. This paper considers political, biopolitical, and material dimensions of waste, focusing on the role of legal processes and institutions. The paper examines a case involving legal accusations of “waste and unreasonable use” of water by the Imperial Irrigation District in Imperial County, California. The determination that water was being “wasted” justified the transfer of water from agricultural to urban areas. However, defining these flows of water as a waste neglected water's complexity and relationality, and the enclosure of a “paracommons” threatens to bring about negative environmental and public health consequences. The paper shows that the project of discursively labeling certain material resource flows as waste and re‐allocating these resources to correct this moral and economic failure relies upon legal processes, and carries political and biopolitical implications.  相似文献   

17.
In this paper, we map the international trade in electronic waste (e‐waste). We quantify the directions and magnitude of this trade at the global scale and examine the utility of the pollution haven hypothesis for explaining the observed trade patterns. Our results demonstrate four key findings: the international trade in e‐waste is a more complex story than being one about ‘rich’ countries dumping waste in ‘poor’ countries; the trade in e‐waste is highly regionalized, with intra‐regional trade accounting for most of the total trade flows; the pollution haven hypothesis is an important, but partial, explanation of observed trade patterns; and there is a need to conceptualize the trade and traffic of e‐waste as open ended and contingent processes facilitated by situated practices of wasting and valuing that rely on geographic difference and mobility for the exchanges between the domains of waste and value to occur.  相似文献   

18.
Abstract. This study implements and tests a mathematical programming model to estimate interregional, interindustry transaction flows in a national system of economic regions based on an interregional accounting framework and initial information of interregional shipments. A national input–output (IO) table, regional data on gross output, value‐added, exports, imports, and final demand at sector level are used as inputs to generate an interregional IO account that reconciles regional economic statistics and interregional transaction data. The model is tested using data from a multiregional global IO database and shows remarkable capacity to discover true interregional trade patterns from highly distorted initial estimates.  相似文献   

19.
Water vapor and ozone concentrations measured at mid and high latitudes above Europe during the MAP/WINE Campaign in the winter 1983/1984 are presented. Both water vapor and ozone distributions are found to be variable and structured. On two occasions strong enhancements of mesospheric ozone were recorded, which were probably caused by dynamic effects. The assumption of a photochemical equilibrium for ozone at high latitudes in winter does not appear justified according to the variations measured during MAP/WINE. Water vapor mixing ratios determined in the stratosphere and mesosphere above Scandinavia yield average mixing ratios of near 4 ppmv.  相似文献   

20.
An increasingly important contributor to the low fertility characteristic of many western societies now experiencing ‘the second demographic transition’ has been the availability of legal pregnancy termination, so much so that national rates of one abortion for every four or five births are not uncommon. Prior to the passage of the 1967 Act legalising abortion in the UK, abortion in Scotland was not actually illegal, but its availability was extremely limited in most areas outside the northeast. Although uptake had increased dramatically in all regions by the mid 1990s, inter‐regional differences in abortion rates remained pronounced. This paper charts regional changes in uptake rates through the period 1974–96 then outlines and tests the effectiveness of ecological models involving socio‐demographic and health‐service related variables in accounting for variations in abortion rates across the thirteen Scottish Health Board regions in 1996. Although deprivation levels, marital and educational status are significantly involved, regional variations in consultant attitudes and professional practice seem also to be important. If the move to free up the availability of the ‘morning‐after pill’ is accepted throughout Scotland such differentials may soon disappear.  相似文献   

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