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Data from the Consensus Economics Forecast Poll is used to analyze how current account forecasters form expectations. The results suggest that forecasts do not satisfy traditional unbiasedness and orthogonality criteria for forecast rationality. In addition, this paper finds anti‐herding behavior among forecasters for the euro area and G7 countries. It also shows that the cross‐sectional heterogeneity with regard to anti‐herding is associated with cross‐sectional heterogeneity in forecast accuracy. More specifically, this paper finds some evidence indicating that forecasters who tend to herd provide more accurate forecasts than their colleagues who follow an anti‐herding strategy.  相似文献   
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We extend the Common Agricultural Policy Regionalised Impact Modelling System (CAPRI) with a regional computational general equilibrium (CGE) model to estimate the effects of the Pillar II of the Common Agricultural Policy. Our aim is to assess the modeling approach by comparing the scenario results with observations from the evaluation reports for rural development, supplemented with expert interviews and findings from the literature. For this purpose, an ex‐post scenario is developed for Germany that models the effect of the Pillar II measures in 2006. We observe a moderate impact, namely, an increase in agricultural income (5%) and agricultural land use (0.15%), particularly grassland, and a substitution of arable land with grassland. This effect leads to a total increase in agricultural production, particularly of beef, and to an increase in total greenhouse gas emissions and total nitrogen surplus for Germany. Greenhouse gas emissions and nutrient surpluses per ha, however, are reduced. We observe that farm investment programmes displace private investment. The evaluation reports confirm the moderate impact and our major results, as does the comparison with other literature. However, the conclusions about agri‐environment measures and their impact on income differ. The most important difference between our results and the evaluation reports and majority of the present literature is that we also quantify the joint effect between the whole economy and policy measures, with some contradictory effects.  相似文献   
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WEB-IS, Web-based Integrated System, allows remote, interactive visualization of large-scale 3-D data over the Internet, along with data analysis and data mining. In this paper, we discuss the overall structure of WEB-IS. Up until now we have developed three sub-modules geared towards geophysical problems. WEB-IS1 allows geoscientists to navigate through their 3-D geophysical data, such as seismic structures or numerical simulations, and interactively analyze the statistics or apply data-mining techniques, such as cluster analysis. WEB-IS2 lets a user control Amira (a powerful 3-D visualization package) remotely and analyze, render and view large datasets across the Internet. WEB-IS3 is an imaging service that enables the user to control the scale of features to view through interactive zooming. In the near future, we propose to integrate the three components together through a middleware framework called NaradaBrokering (iNtegrated Asynchronous Real-time Adaptive Distributed Architecture, a distributed messaging infrastructure that can be used to intelligently route data between the originators and registered consumers) without regard for time or location. As a result, WEB-IS will improve its scalability and acquire properties of fault-tolerance. WEB-IS uses a combination of Java, C++, and through the use of NaradaBrokering will seamlessly integrate the server-side processing and user interaction utilities on the client. The server takes care of the processor intensive tasks, such as visualization and data mining, and sends either the resulting bitmap image or statistical results to the middleware across the Internet for viewing. WEB-IS is an easy-to-use service, which will eventually help geoscientists collaborate from different sites in a natural manner. It will be very useful in the next 10 years because of the increasing number of space missions and geophysical campaigns.  相似文献   
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High yield gaps persist in sub‐Saharan Africa and increased fertilizer use is considered among the crucial measures to increase productivity. Despite high government investments, particularly in fertilizer subsidy programs (FSPs), overwhelming evidence has revealed their inefficiency. This study employs a multidisciplinary approach to identify the determinants of low maize yields in the Guinea savanna zone of Ghana. We conducted a socioeconomic household survey and analyzed plot‐specific soil samples. Econometric models were estimated based on both socioeconomic and soil variables. The results show that a common parasitic weed, Striga, and labile soil structure have significant effects on yield in the study region. Plot sizes were recorded both from farmers’ direct elicitation and using GPS devices. Considerable discrepancies were detected between self‐reported and GPS‐measured plot sizes. Fertilizer samples from randomly selected agro‐input shops were analyzed to control for adulterated or fake inputs. The measured nutrient contents of the samples reflected the composition indicated on the package labels. Findings underline the need of site‐specific data collection, supported by laboratory‐based soil test results, to efficiently address low productivity. Although there are no signs of fertilizer adulteration, governance challenges persist in targeting, timing, and elite capture in the distribution system of the subsidy program. The study shows that the FSP has not been an effective standalone measure. Rather, the government needs to invest in capacity building and extension services to address the site‐specific problems through comprehensive soil fertility management techniques and weed control. Promoting soil carbon management, minimum mechanical stress, crop rotation, and permanent soil cover should be further investigated as options for the region.  相似文献   
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