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11.
A new generation of greenways has emerged in recent years, the most ambitious of which are nationwide, interconnected networks of multi-use, multi-purpose greenways and trails, clustered under a single national vision. However, because these initiatives have been the focus of so few research studies, opportunities to glean lessons from their planning and implementation have been limited. This paper contributes to addressing this knowledge gap by presenting a comparative account of two networks, the Trans Canada Trail in Canada and Sendero de Chile in Chile. Using document analysis and interviews with officials closely involved in their development, the evolution of both networks is documented over time, emphasizing similarities and differences related to their planning and implementation. Both initiatives have faced significant challenges in reaching their connection goals and have availed themselves of a diverse range of opportunities and strategies to advance their agendas. A simple model of a virtuous cycle is proposed to highlight the positive feedback—between political and public support, sustained funding, partnership development, accessibility for urban residents, and connectivity of the network—generated by sustained network expansion over time. It is hoped that the insights offered from this analysis may offer guidance to inform the development of similar scale projects elsewhere.  相似文献   
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We analyze the general equilibrium effects of an asymmetric decrease in transport costs, combining a large-scale spatial dynamic general equilibrium model for 267 European NUTS-2 regions with a detailed transport model at the level of individual road segments. As a case study, we consider the impact of the road infrastructure investments in Central and Eastern Europe of the European Cohesion Policy. Our analysis suggests that the decrease in transportation costs benefits the targeted regions via substantial increases in gross domestic product (GDP) and welfare compared to the baseline, and a small increase in population. The geographic information embedded in the transport model leads to relatively large predicted benefits in peripheral countries such as Greece and Finland, which hardly receive funds, but whose trade links cross Central and Eastern Europe, generating profit from the investments there. The richer, Western European nontargeted regions also enjoy a higher GDP after the investment in the East, but these effects are smaller. Thus, the policy reduces interregional disparities. There are rippled patterns in the predicted policy spillovers. In nontargeted countries, regions trading more intensely with regions where the investment is taking place on average benefit more compared to other regions within the same country, but also compared to neighboring regions across an international border. We uncover that regions importing goods from Central and Eastern Europe enjoy the largest spillovers. These regions become more competitive and expand exports, to the detriment of other regions in the same country.  相似文献   
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The standard theory of optimal jurisdictional size hinges on the existence of economies of scale in the provision of local public goods and services. However, despite its relevance for forced local amalgamation programs and related policies, the empirical evidence on the existence of such economies of scale remains elusive. The main goal of this paper is to produce an updated and comprehensive quantitative review of the existence of economies of scale in the provision of local public goods using a meta-analysis approach to systematize the wide range of empirical approaches and modeling frameworks found in the previous literature. Our analysis confirms the presence of moderately increasing to constant returns to scale in the provision of local services with no reduction in the average costs of production in the delivery of most local public services beyond a certain, modest jurisdictional size, which many studies have estimated at 10,000 residents. Also, the potential for economies of scale differs at least across three traditional services: education, water and sanitation, and garbage collection, being highest for education and lowest for garbage collection. Our analysis also offers guidelines for future empirical research in this area. Physical output and production cost data should be used, together with translog specifications for the modeling of cost functions. Last, we find evidence that the determinants of output cost elasticity include bidirectional publication bias and population density but do not include the presence or absence of modern “lean” production technologies or the (perceived) capital intensity of the sector, contrary to conventional wisdom. These findings have significant policy implications for countries considering jurisdictional consolidation programs.  相似文献   
14.
In this paper, we develop a three-region economic geography model with workers of heterogeneous skills and mobility rates to consider how first-nature, regional differences impact both inter- and intraregional inequality. In our model, the skill premium within a region summarizes both the degree of intraregional inequality between mobile, skilled workers and immobile, unskilled workers and the interregional inequality through differences in the welfare of unskilled workers across regions. Regions with the highest skill premium have the greatest degree of intraregional inequality and provide the lowest level of welfare to unskilled workers, relative to other regions. We find that the skill premium will be higher in regions with a greater supply of unskilled labor, lower supply of housing, or are more remote. An increase in a region's housing supply or centrality will lower intraregional inequality and raise the welfare of the local, unskilled workforce. However, the magnitude of these changes are declining in the initial number of skilled workers in the region. The model is extended to consider imperfectly elastic housing supply. The larger the price elasticity of housing, the larger the range of values, such that more populated regions will host a disproportionate share of skilled workers, have lower levels of intraregional inequality, and provide higher levels of welfare for unskilled workers.  相似文献   
15.
This paper analyses social transformations in the Early Iron Age based on a holistic and longue durée approach applied to the first fortified habitats in the Iberian north-west. Through a comprehensive review of two paradigmatic settlements of the EIA in the province of A Coruña (Galicia, north-west Iberia), Punta de Muros and A Graña, a comparison is drawn between the social and territorial dynamics of this period by means of an in-depth analysis of the main characteristics of both settlements. Accordingly, a greater level of social complexity during the phases of occupation of the settlement of Punta de Muros has been identified, in contrast to the resistance to change observed in A Graña. Based on these conclusions, the role of metalworking and its symbolic value in fostering and legitimizing these social and territorial transformations and in the development of Iron Age communities are analysed.  相似文献   
16.
This guest editorial reflects on the relevance of anthropology for extinction concerns, a rapidly expanding practical, ethnographic and theoretical space at a time of impending mass extinction. While biological extinction is necessarily a multispecies development (usually implicating humans), traditional species talk – focused on taxonomies, collections and classification – needs critical rethinking as it necessarily diverts attention from the vitality of life. The broad discipline of anthropology has much to offer for understanding processes of extinction and recovery, fleshing out habitat problems and prospects of extinction, and advancing meaningful environmentalist practices.  相似文献   
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The original fineness of coins is very important information that can help us to understand the commercial situation in a wide historical context. This paper deals with a comparison of analytical methods suitable for the evaluation of the actual and original fineness of coins based on a detailed case study of a medieval coin sample. Both non‐destructive (i.e., scanning electron microscopy/energy‐dispersive X‐ray spectroscopy, X‐ray fluorescence, atomic force microscopy and hydrostatic weighing) and destructive (i.e., inductively coupled plasma – mass spectrometry and the Volhard titration method) techniques were used. The original fineness can be also deduced from knowledge of the internal structure of the coin (limited miscibility of copper and silver). A new analytical method based on a combination of a micrograph of the metallographic cross‐section with consequent image analysis was developed for determination of the original fineness. The proposed approach is relatively simple and provides reliable values. Sample heterogeneity and its impact on the determination of fineness are also discussed.  相似文献   
20.
This article presents a Bayesian method based on spatial filtering to estimate hedonic models for dwelling prices with geographically varying coefficients. A Bayesian Adaptive Sampling algorithm for variable selection is used, which makes it possible to select the most appropriate filters for each hedonic coefficient. This approach explores the model space more systematically and takes into account the uncertainty associated with model estimation and selection processes. The methodology is illustrated with an application for the real estate market in the Spanish city of Zaragoza and with simulated data. In addition, an exhaustive comparison study with a set of alternatives strategies used in the literature is carried out. Our results show that the proposed Bayesian procedures are competitive in terms of prediction; more accurate results are obtained in the estimation of the regression coefficients of the model, and the multicollinearity problems associated with the estimation of the regression coefficients are solved.  相似文献   
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