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91.
This paper is motivated by automated valuation systems, which would benefit from an ability to estimate spatial variation in location value. It develops theory for the local regression model (LRM), a semiparametric approach to estimating a location value surface. There are two parts to the LRM: (1) an ordinary least square (OLS) model to hold constant for interior square footage, land area, bathrooms, and other structural characteristics; and (2) a non-parametric smoother (local polynomial regression, LPR) which calculates location value as a function of latitude and longitude. Several methods are used to consistently estimate both parts of the model. The LRM was fit to geocoded hedonic sales data for six towns in the suburbs of Boston, MA. The estimates yield substantial, significant and plausible spatial patterns in location values. Using the LRM as an exploratory tool, local peaks and valleys in location value identified by the model are close to points identified by the tax assessor, and they are shown to add to the explanatory power of an OLS model. Out-of-sample MSE shows that the LRM with a first-degree polynomial (local linear smoothing) is somewhat better than polynomials of degree zero or degree two. Future applications might use degree zero (the well-known NW estimator) because this is available in popular commercial software. The optimized LRM reduces MSE from the OLS model by between 5 percent and 11 percent while adding information on statistically significant variations in location value.  相似文献   
92.
我国农村土地制度的产权经济分析   总被引:1,自引:0,他引:1  
近年来我国农村发生了土地制度的深刻变革,变革的核心是土地产权制度的变迁。这种制度变迁在某种程度上具有帕累托改进的性质,但在某些方面还有待于发展和完善。我国农村土地产权制度建设的思路:以现行产权制度为基础,通过修订和完善,不断发挥现行产权制度的积极作用。  相似文献   
93.
目前我国土地管理中存在着土地市场不完善.国土基金管理不到位等问题。应完善我国土地市场和加强国土基金使用管理。应加快土地资源的市场配置.完善国有土地有偿使用制度.推进国有土地使用权的招标、拍卖和挂牌出让。建立土地收购储备制度.以促进土地的可持续利用。完善城镇土地的出租制.采取长租、短租或临时出租等方式,以保证土地的长期收益。建立集体土地流转制度。成立国土基金专户.国土基金专款专用.收支两条线.实行国土基金的计划管理制度和监管制度。  相似文献   
94.
Standard New Keynesian models have often neglected temporary sales. In this study, we ask whether this treatment is appropriate. We use Japanese scanner data covering the last two decades and find a negative correlation between the frequency of sales and hours worked. We then construct a model that takes households' decisions regarding their allocation of time for work, leisure, and bargain hunting into account. We show that the decline in hours worked explains the rise in the frequency of sales. The real effect of monetary policy shocks weakens by around 40% due to temporary sales, but monetary policy still matters.  相似文献   
95.
Natural vegetation enhances the value of agricultural landscapes for people and wildlife. However, the role of anthropogenic versus topographic factors in driving the extent of natural vegetation cover within agricultural lands at large spatial scales remains unexplored. I assessed the influence of anthropogenic and topographic variables on the extent of agricultural mosaics with high natural vegetation cover in the country of Turkey where a large extent of natural and semi-natural vegetation is maintained by traditional agriculture. GIS layers depicting human land use, elevation, slope, roads and population data were obtained and summarized at two spatial scales, within provinces and for 100 km2 grid cells covering the country’s entire agricultural land area. Average farm size was also obtained at province level. Hierarchical Partitioning was conducted to determine the independent effect of anthropogenic and topographic variables on the variation in agriculture with high natural vegetation. Slope had the largest independent effect on the variation in the proportion of agricultural mosaic with high natural vegetation cover. The extent of agricultural and settlement area also explained much of the variation in natural vegetation across both grid cells and provinces. The proportion of natural vegetation increased as human population and road density decreased across grid cells and as average farm size decreased across provinces. These results suggest that while topography is the primary driver of natural vegetation cover within agricultural mosaics in Turkey, the pressures associated with urban development and agricultural industrialization may also influence the cultural and wildlife value of agricultural landscapes.  相似文献   
96.
This special issue integrates eleven papers focussing on indicators able to convey the multiple expectations that society has concerning agricultural land. As scale issues have been so far overlooked within this research topic, a particular focus of this themed issue is to highlight the need for reconciling assessments across scales. The shared purpose of the contributions is to examine how the multiple societal expectations concerning agrarian landscapes might be incorporated into land use policy at different governance levels.A core set of these papers were presented in the symposium “Linking social indicators across scales”, to the European Congress of the International Association of Landscape Ecology (IALE) in September 2013 in Manchester, UK. This symposium was organized to create the time and space for a discussion on the issues of scale when capturing societal preferences concerning agrarian landscapes. While the landscape scale was specifically addressed by four papers, seven papers examined broader geographic units in addition to up-scaling and downscaling issues.  相似文献   
97.
Land exploitation, as an important strategy to mitigate farmland loss and stabilize grain production, has been adopted to compensate farmland loss due to rapid urbanization in China. Bounded by the limited capacity and obvious spatial variations of national farmland reserves, it is essential to arrange land exploitation activities timely and reasonably. In this study, we propose an indicator for the status of regional land exploitation, the Exploitation Degree, to facilitate an overview of land exploitation programs in China at both provincial and prefectural levels based on project data from 2006 to 2012. To further our understanding of the regional features of land exploitation activities, we employ the Lasso model to identify and quantitatively assess influencing factors on land exploitation. Our study shows that: (1) contemporary land exploitation practices in China are significantly inconsistent across exploitable farmland reserves. Some areas are greatly over-exploited and such irrational land exploitation has been persistent; (2) related national land plans designed to guide land exploitation efforts centered on resource-rich regions and critical areas do not function as intended. Therefore, we suggest that China⿿s land exploitation policy shall be improved by reconsidering the orientation of land exploitation policy, coordinating land exploitation activities with productivity improvements and eco-system protection, and enhancing the power and scope of the plans in controlling and guiding land resource management.  相似文献   
98.
This paper focuses on the estimation of direct damages caused by three flood scenarios with different return periods in the section Făgetul de Sus – Ghimeş – Palanca Pass of Trotuș River, with the aim of highlighting the need of improved land use plans. The damage for three land use classes (residential building, infrastructure and agriculture) were estimated using the damage curves developed by the European Joint Research Centre (JRC) as well as site specific maximum damage values. The data were processed with the help of the ArcMap 10.2 software and FloodRisk tool from QGIS software. Furthermore, the flood risk was assessed using the damage – probability curves, which associates the damage with the corresponding frequency of occurrence. This method was identified and adapted to the characteristics of the study area in order to develop a methodology of flood risk assessment that is answering the question: does the lack of land use plans increase the vulnerability and the flood damage? The results showed that the greatest damages are registered for the residential building land use class for a flood probability of 0.001. In this case the damages reach up to 60% on the scale range of deterioration factor, the total damage value being 2 million euros. For the same hazard probability the total registered damage value for roads is 7500 euro, for railways is around 12,000 euro, while for agriculture is around 84,000 euro. These results highlight the need of protection measures and land use plans development and implementation. Regarding the protection measures we consider that the egalitarianism would be the concept that should be applied in the study area and also an improved cooperation between government, specialized agencies and local authorities at local level would lead to a more efficient flood risk management process. The proposed methodology can be applied for micro-scale analysis, providing quantitative results regarding the flood damage and flood risk assessment. It includes a detailed vulnerability analysis of the elements-at-risk with the aim of developing a more comprehensive approach of flood risk assessment.  相似文献   
99.
Problems in agriculture and land use are increasingly recognised as complex, uncertain, operating at multiple levels (field to global value chains) and involving social, economic, institutional, and technological change. This has implications for how projects navigate complexity to achieve impact. However, few studies have systematically evaluated how project actors engage with other actors to configure capabilities and resources across multiple levels in agricultural innovation systems (AIS), from the individual to the network, to mobilise and build systemic innovation capacity. An analytical framework conceptualising the nested configuration of capabilities at multiple levels in the AIS is applied to two projects that successfully tackled agricultural and land management problems of differing complexity: (i) improving lamb survival; and (ii) sustainable land management in New Zealand. Findings indicate that innovation capacity constitutes project actors interacting with other AIS actors to configure capabilities and resources at different levels of the AIS in order to leverage positive project path dependencies and break path dependencies that are created by existing and historical capability configurations. Project actors also balance exploiting existing innovation capabilities, as well as using adaptive capability for exploring and creating new capability configurations to respond to emerging circumstances. This implies that projects should have strategic ambidexterity in terms of how they combine exploiting existing and exploring new networks to access, combine, create, or disconnect certain capabilities to address ‘capability voids’ in AIS. This requires support to projects to constantly scrutinise, through reflexive monitoring by dedicated facilitators, specific agriculture and land use policies connected to major sustainable development models (e.g. climate smart agriculture, urban farming, smart farming). The can help assess whether the AIS provides the right mix of capabilities and whether this is adequately supported by innovation policy, to realize transformative policy objectives.  相似文献   
100.
The spread of free trade agreements (FTAs) in Southeast Asia has ignited a debate about their impact on enterprises including the business costs from the Asian ‘noodle bowl’ effect. This paper undertakes a comparative and firm-level analysis of the determinants of FTA use in Indonesia, Malaysia and the Philippines. The likelihood of firms using important ASEAN+1 FTAs (e.g. the ASEAN-China FTA, the ASEAN-Japan FTA and ASEAN-Korea FTA) is positively associated with acquiring knowledge about FTAs, building technological capabilities, and membership in industrial clusters. Non-use of FTAs is explained by a lack of information about FTAs and the absence of FTAs with major trading partners. Key policy implications are the need to improve business support for FTAs, to conclude FTAs with major trading partners, and to create a database on FTA preference use.  相似文献   
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