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We find that bond price quotes impound bad earnings news on a more timely basis than good earnings news and that the bond market impounds bad news on a more timely basis than the stock market. We also find that the timeliness of the bond market reaction to bad news is concentrated primarily among speculative‐grade bonds, consistent with earnings news having a larger effect on bond price quotes when default risk is high. In addition, we find that a portion of the bad news impounded by the bond market reverses following the earnings announcement. Overall, our findings are consistent with bondholders’ asymmetric payoff function having important implications for the valuation role of accounting information in the bond market. Specifically, our findings indicate that bond quotes impound bad earnings news much earlier in the pre‐earnings announcement period than stock prices. In addition, bondholders appear to overreact to the bad earnings news initially and correct this overreaction subsequent to the earnings announcement.  相似文献   
965.
In this viewpoint we draw on insights from participatory agri-environmental policy making, spatial planning and collaborative approaches to environmental management. We propose steps for planning, design and implementation of agri-environmental payment schemes that will encourage collaboration and co-ordinated actions at a landscape scale to contribute more effectively to the continued provision of ecosystem services.  相似文献   
966.
The Agri-Environment Footprint Index (AFI) has been developed as a generic methodology to assess changes in the overall environmental impacts from agriculture at the farm level and to assist in the evaluation of European agri-environmental schemes (AES). The methodology is based on multi-criteria analysis (MCA) and involves stakeholder participation to provide a locally customised evaluation based on weighted environmental indicators. The methodology was subjected to a feasibility assessment in a series of case studies across the EU. The AFI approach was able to measure significant differences in environmental status between farms that participated in an AES and non-participants. Wider environmental concerns, beyond the scheme objectives, were also considered in some case studies and the benefits for identification of unintentional (and often beneficial) impacts of AESs are presented. The participatory approach to AES evaluation proved efficient in different environments and administrative contexts. The approach proved to be appropriate for environmental evaluation of complex agri-environment systems and can complement any evaluation conducted under the Common Monitoring and Evaluation Framework. The applicability of the AFI in routine monitoring of AES impacts and in providing feedback to improve policy design is discussed.  相似文献   
967.
This article suggests a pricing model for commodities used to produce biofuel. The model is based on the concept that the deterministic component of the Wiener process is not constant and depends on time and exogenous variables. The model, which incorporates theory of storage, the convenience yield and the seasonality of harvests, was applied in the Brazilian sugar market. After predictions were made with the Kalman filter, the model produced results that were statistically more accurate than those returned by the two‐factor model available in the literature.  相似文献   
968.
In highland Bolivia, potato markets are widespread and access to market information has entered the digital age. Information networks lubricated by ubiquitous cellular technologies are supplanting traditional means of information‐gathering. We explore the impacts of access to cellular phones on market selection, use of social networks to acquire information, and gendered responsibilities within the potato market chain near Cochabamba. The entire family participates in potato production and marketing, but responsibilities are differentiated by gender. Men take a leading role in potato production and women in marketing. Access to cellular phones affects decisions about where to market potatoes and improves the potato marketing process.  相似文献   
969.
Challenges for land system science   总被引:3,自引:0,他引:3  
While considerable progress has been made in understanding land use change, land system science continues to face a number of grand challenges. This paper discusses these challenges with a focus on empirical land system studies, land system modelling and the analysis of future visions of land system change. Contemporary landscapes are contingent outcomes of past and present patterns, processes and decisions. Thus, empirical analysis of past and present land-use change has an important role in providing insights into the socio-economic and ecological processes that shape land use transitions. This is especially important with respect to gradual versus rapid land system dynamics and in understanding changes in land use intensity. Combining the strengths of empirical analysis with multi-scale modelling will lead to new insights into the processes driving land system change. New modelling methods that combine complex systems thinking at a local level with macro-level economic analysis of the land system would reconcile the multi-scale dynamics currently encapsulated in bottom-up and top-down modelling approaches. Developments in land use futures analysis could focus on integrating explorative scenarios that reflect possible outcomes with normative visions that identify desired outcomes. Such an approach would benefit from the broad and in-depth involvement of stakeholders in order to link scientific findings to political and societal decision-making culminating in a set of key choices and consequences. Land system models have an important role in supporting future land use policy, but model outputs require scientific interpretation rather than being presented as predictions. The future of land system science is strongly dependent on the research community's capacity to bring together the elements of research discussed in the paper, via empirical data collection and analysis of observed processes, computer simulation across scale levels and futures analysis of alternative, normative visions through stakeholder engagement.  相似文献   
970.
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