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51.
根据2011-2014年科技部《国家重点科技基础条件资源调查表》以及国家统计年鉴数据,首先,使用赫芬达尔指数定量描述了利用国家重点科技资源进行创新活动的非均衡性。其次,使用网络DEA方法,实证分析了2012-2014年中国(内地)各省份国家重点科技资源对区域创新发展的支撑作用。研究表明,国家重点科技资源对区域创新发展的支撑作用不仅取决于资源创新生产阶段,而且受制于重点科技资源支持下的区域创新发展阶段。重点科技资源的支撑作用还有较大提升空间,70%的省份创新成果转化能力有待提高,且大部分省份的国家重点科技资源未实现优化配置。此外,全国及东部、中部和西部国家重点科技资源对区域创新发展的支撑效率不存在绝对收敛趋势。  相似文献   
52.
This work assesses the causal impact of the EU trade preferences granted to the Southern Mediterranean Countries (SMCs) in agriculture and fishery products over the period 2004–2014. It overcomes some of the weaknesses of previous assessments and presents several methodological improvements. Firstly, it relies on a continuous treatment – i.e. preferential margins – to capture the ‘average treatment effect’ of trade preferences, rather than on a binary treatment based on dummy variables. Secondly, it uses highly disaggregated data at sectoral level in order to evaluate properly the preferential treatment. Thirdly, it applies a non-parametric matching technique for continuous treatment – specifically, a generalized propensity score matching. The results show, on the one hand, that the impact of the EU preferences is positive and significant on SMCs trade and is better evaluated using impact evaluation techniques. On the other hand, they demonstrate that the relationship between preferences and trade flows is asymmetric and warn against the risk of providing too much of a good thing. These results raise important issues for policy-making. First, they demonstrate that raising the level of preferences is not the solution to foster the SMCs trade towards EU. Second, that the policy-makers should put more emphasis on complementary factors other than trade barriers.  相似文献   
53.
Land use change is strongly modifying the traditional landscape of hilly productive Mediterranean sites. An example of these circumstances is the Langhe region (Piemonte, NW Italy), where woody plantations such as vineyards and orchards have been cultivated on hillslopes for centuries. In this paper we assess landscape changes occurred in the Diano study area (2651 ha) in the 1954–2000 period and we ascertain land use transition paths and rates of this rural ecosystem. Land use mapping obtained from object-oriented analysis of aerial photographs was used to quantify land use changes between 1954 and 2000. To examine the spatio-temporal patterns of land use change over time, a set of spatial statistics capturing different dimensions of landscape change was identified. An increase of landscape heterogeneity from 1954 to the present was observed due to the expansion of orchards and the fragmentation of field crops. A significant portion (55%) of current orchards surface is represented by former field crops, 24% by vineyards and 15% by forests. The strong expansion of hazelnut orchards concurred to the fragmentation of traditional rural landscape was dominated by vineyards, field crops and forests. Hazelnut orchards expansion was mainly located in places where grapes cultivation was less remunerative. A further expansion of hazelnut in the area should be planned, discussed and carefully monitored through change detection studies in order to avoid potential unsustainable use of the land.  相似文献   
54.
In this study, we analyze the regulation of markets for the provision of services whose costs are subsidized for paternalistic reasons. We model the choice of a benevolent regulator who wants to maximize consumer welfare in a setting where quality cannot be verified and the good provided is fully subsidized. The choice is thus made between two types of providers (profit maximizers and altruistic providers) and two frameworks (monopoly franchise and quality competition). Our analysis shows that in this environment the performance of mixed markets is always dominated by pure forms. Moreover, although making efficient providers compete for the market minimizes cost, the choice of quality competition with altruistic providers may be preferable from a welfare point of view whenever service quality is relevant and the productivity differential is not substantial.  相似文献   
55.
The daily trip to work is ubiquitous, yet its characteristics differ widely from person to person and place to place. This is manifested in statistics on mode and distance of travel, which vary depending on a range of factors that operate at different scales. This heterogeneity is problematic for decision makers tasked with encouraging more sustainable commuter patterns. Numerical models, based on real commuting data, have great potential to aid the decision making process. However, we contend that new approaches are needed to advance knowledge about the social and geographical factors that relate to the diversity of commuter patterns, if policies targeted to specific individuals or places are to be effective. To this end, the paper presents a spatial microsimulation approach, which combines individual-level survey data with geographically aggregated census results to tackle the problem. This method overcomes the limitations imposed by the lack of available geocoded micro-data. Further, it allows a range of scales of analysis to be pursued in parallel and provides insights into both the types of area and individual that would benefit most from specific interventions.  相似文献   
56.
Spatial modeling of economic phenomena requires the adoption of complex econometric tools, which allow us to deal with important methodological issues, such as spatial dependence, spatial unobserved heterogeneity and nonlinearities. In this paper we describe some recently developed econometric approaches (i.e. Spatial Autoregressive Semiparametric Geoadditive Models), which address the three issues simultaneously. We also illustrate the relative performance of these methods with an application to the case of house prices in the Lucas County.  相似文献   
57.
This paper uses spatial panel methods and Chinese provincial data from 2003 to 2017 to study the spatial spillovers of financial openness on economic growth. The results show, first, a positive direct effect and an overall negative spatial spillover of financial openness on provincial growth. Second, there are two spatial spillover channels: a positive growth externality and a harmful resource competition among provinces. Third, we estimate the state dependence and dynamics of spatial spillover, and find that the negative spatial spillover is smaller in provinces with high levels of financial openness and in the long term; thus, the negative spatial spillover declined over time. These results are robust to the choice of SDM and GNS spatial econometrics methods and under different spatial weight matrices.  相似文献   
58.
This paper contributes to debates about the appropriate characterisation of heterogeneous investment types and to what extent different investment motives affect the responsiveness to corporate taxation. In particular, we employ and refine a methodology to better evaluate the tax elasticity of investment types. Using a combination of both firm‐specific information and sector‐specific information from input–output tables, we discuss how to classify investment as non‐related, horizontal, vertical and complex types. First, we point out to what extent the resulting classification depends on assumptions made by the researcher. Second, we employ an ample set of classifications and find that non‐related investment reacts stronger to corporate taxation, whereas horizontal investment is less responsive, though, significant negative tax semi‐elasticities turn out for the subset of manufacturing industries. To address inherent characteristics of vertical and complex investment, we extend the methodology and find that, by and large, stronger business motives reduce the tax responsiveness of investment to a larger extent. Given the current debates about substantial corporate tax reforms, it is all the more important to recognise that corporate tax effects can vary fundamentally between countries, driven by country‐specific differences in their composition of industries and investment types.  相似文献   
59.
经济软实力是决定经济发展方式转型的关键因子,经济软、硬实力的不同配置决定经济发展方式类型。经济软实力不仅内在具有推动经济发展方式转型的能力,而且还具有实现其转型的内在机理。通过河南省区域经济软实力空间分布及其与区域发展指数关联的实证分析,证明以提升经济软实力促进区域经济发展方式转变是经济发展的一种必然规律。  相似文献   
60.
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