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71.
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   
72.
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   
73.
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   
74.
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   
75.
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   
76.
Differences in the internal composite structure during urban built-up land sprawl (UBLS) will generate different effects, and thus, a city’s spatial structure has important bearings on urban sustainability. This study investigates the spatial and temporal characteristics of the internal structure and allocation relationship of UBLS using multivariate spatial correlation and the Weaver-Tomas composite coefficient based on site data of granted built-up land parcels. Moreover, the composite structure evolution process of UBLS and its driving mechanism are examined in this study. The results reveal that the amount structure of the three types of UBLS (i.e. industrial land sprawl, residential land sprawl and commercial land sprawl) tended to be balanced during the study period. Following the transformation and upgrade of the urban industry structure, the overall composite structure of UBLS ranged from single residential land-use structure (Res.) to industrial-residential land-use structure (Ind.-Res.) In the early period of land marketization, the marketization land granting mechanism caused low spatial correlation between the various types of UBLS and a single composite structure, i.e. Res., single commercial land-use structure (Com.), and residential-commercial land-use structure (Res.-Com.). Subsequently, a dual-driving force including the market economy and government interventions caused a relatively high degree of spatial correlation and a multiple composite structure, i.e. Ind.-Res. and industrial-residential-commercial land-use structure (Ind.-Res.-Com.). However, the evolution characteristics of the composite structure in various regions illustrate some problems, such as the spatial isomorphism phenomenon of the composite structure and the dislocation of urban built-up land allocation. The urban internal built-up land spatial layout pattern is the embodiment of two dominant driving forces, the market and the government, interacting with each other according to natural and socioeconomic conditions. Therefore, we suggest that it is necessary to reform the future urban built-up land granting mechanism based on market guidance, and the composite structure of UBLS should be adjusted according to the regional function. The government should reinforce the macro-control of land-use planning for the dispersed granted land parcels so as to optimize the urban land-use structure.  相似文献   
77.
Food trucks represent a temporary use of vacant or underutilised land. They have been assumed to increase the livability, vibrancy and attractiveness of a neighbourhood. However, no previous study has investigated whether this effect is reflected in property prices within the surrounding neighbourhood. We investigate the impact of a food truck pod on the values of single-family homes nearby. Using a quasi-experimental design, transaction data from Portland, Oregon and a difference-in-difference specification of a spatial regression model, we find that food trucks actually represent a negative externality, and that proximity of a home to food trucks is penalised by homebuyers. The closer a home is to the food trucks, the lower is the sales price. Explanations for this effect include increased parking shortages and trash issues in a neighbourhood due to food truck visitors.  相似文献   
78.
Mobilising under-utilised low carbon (ULC) land resources for future agricultural production can help reducing pressure on high carbon stock land from agricultural expansion, particularly for deforestation hotspots like Kalimantan. However, the potential of ULC land is not yet well understood, especially at regency level which is the key authority for land-use planning in Indonesia. Therefore, this study explored ULC land resources for all regencies in Kalimantan. By analysing information from six monitoring domains, a range of indicators were derived to provide insights into the physical area of ULC land from various perspectives. It was found that these indicators show largely different values at regency level. For example, regency Pulang Pisau has a substantial area of ‘temporarily unused agricultural land’ but a very limited area of ‘low carbon land’ – this implies that not all ‘temporarily unused agricultural land’ is ready for future exploitation when assessing from different aspects. As a result of such diverging indicators, using a single indicator to quantify available ULC land resources is risky as it can either be an over- or under-estimation. Thus, ULC land resources were further explored in the present paper by taking four regencies as case studies and comparing all the indicators, supported with relevant literature and evidence collected from narrative interviews. This information was used to estimate ULC land area by possible land-use strategies. For example, Gunung Mas was found to have a large area of low carbon land which is not occupied and might be suitable for oil palm deployment. However, the major limitation is that physical estimates cannot provide a complete picture of ‘real’ land availability without considering a broader range of socio-economic factors (e.g. labour availability). Therefore, physical land area indicators from different domains must be combined with other qualitative and quantitative information especially the socio-economic factors underlying land under-utilisation to obtain better estimates.  相似文献   
79.
In the 1990s, the Democratic People’s Republic of Korea (North Korea) suffered from severe food shortages and large-scale deforestation, which triggered a stage of rural conservation reform. Since 2004, with support from the Swiss Agency for Development and Cooperation (SDC), North Korea’s Ministry of Land and Environmental Protection (MoLEP) has implemented a Sloping Land Management Program (SLMP). The SLMP established sloping land user groups and granted these groups the right to use marginal land for agroforestry development. This devolution of land rights from state control onto local groups is a landmark in North Korea, and this decentralization initiative has now expanded to over eight counties to involve thousands of households. It has also led to the launch of a National Agroforestry Policy and Strategy. Drawing from both qualitative and quantitative data collected from 2008 to 2014, this paper documents the process and effects of the SLMP. It argues that the decentralization reform in land management has contributed to not only food security with increased food crop diversity and productivity, but also notably forest recovery through an expansion of tree plantations and agroforestry practices on degraded sloping lands. However, an insufficient power transfer in the form of a lack of timber rights granted to the local user groups has hampered the effectiveness of the SLMP. There are also institutional and geopolitical challenges that are limiting further scaling-up of land-use decentralization across the country. The policy implication calls for more international investment as well as national land-use policy reforms in order to promote and facilitate further decentralization of sloping land management and to secure greater use rights for sloping land user groups.  相似文献   
80.
The planned economy system’s previous form of industrial land market control in China has led to current market failure because of a large amount of industrial land being sold at a very low price, causing extensive overuse of land and negative effects on land management. As the “World Factory”, the Pearl River Delta (PRD) is well known for its rapid urbanization largely driven by Foreign Direct Investment in labor-intensive industries. A low-land price strategy has been commonly adopted by the local government in order to attract industrial investment. In the past decade, the PRD has increasingly faced the increasing competition from its neighboring competition from its neighboring countries in Southeast Asia that have established preference policies to attract FDI and foreign enterprises. Despite a growing body of literature on the internal forces of industrial land in China, little is known of the external forces involved except for the importance of FDI and the intensity of interregional competition between China and other countries in attempting to attract foreign investment. This research fills the knowledge gap by modeling the situation in the form of an international cooperative game model aimed at revealing the industrial land price formation mechanism between the PRD region and Southeast Asian regions. The conditions of industrial land in the area and several Southeast Asian countries are first analyzed for their industrial land price movements in recent years. A game theoretic model is then built that exhibits similar characteristics. The result indicates that the governments’ low land price strategy and the competition between the PRD and its neighboring countries have created unnecessarily high social and environmental costs. Policy suggestions are made to encourage a more appropriate use of industrial land in China, and the most important being the need for a mindset shift from competition towards coopetition between the PRD and Southeast Asian regions.  相似文献   
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