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991.
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   
992.
This study explores the effects of Vietnam's transition on the welfare of different ethnic groups in rural Vietnam. It draws on three rounds of national household surveys in 2002, 2004 and 2006. It is first observed that the pace of poverty reduction for minorities surpassed the majority over the period 2002–2006, although poor people were still concentrated in the minority groups throughout the period. Secondly, the disparity in living standards has been widening. In particular, inequality within both the majority and minority groups increased over the period. Thirdly, the study shows that the effect of economic growth on poverty is estimated to have been greater if inequality remained constant. It is also noted that the impacts of economic growth on poverty vary across different ethnic groups. Finally, regression decompositions of within inequality have confirmed that the main driver of inequality is not the same among ethnic groups. Given the diversity across different ethnic groups, we can conclude that government policy aimed at equal access to infrastructure and more equal distribution of assets, such as land, for ethnic minority groups would lead to more equal distribution of consumption and poverty reduction of those groups. Also, consideration of local needs would be necessary in designing and implementing public policies, given the heterogeneous socio-economic circumstances surrounding each ethnic minority group.  相似文献   
993.
We test for the existence of market discipline by shareholders of banks with a wide range of ownership structures. Discipline by shareholders manifests itself through monitoring banks’ level of risk as well as through influencing banks’ management actions. We find that shareholders utilize the relation between stock returns and different types of risk measures to monitor risky banks. Shareholders partially influence bank management by responding to decreasing stock returns with a demand to improve loan quality. Moreover, the influence on management in small banks is more pronounced compared to large banks.  相似文献   
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Recent learning-by-doing research highlights the importance of examining multiple measures of experience and their relationship to the performance of work teams. Our paper studies the role of individual experience, organizational experience, team leader experience, and experience working together on a team (team familiarity) in the context of improvement teams. To do so, we analyze successful and failed six sigma improvement team projects at a Fortune 500 consumer products manufacturer with multiple business groups. Such improvement project teams focus on deliberate learning, which differs from the primary focus of work teams.Our analysis uses archival data generated by these improvement project teams over a six year time span. Of the four experience variables we study, we find that team leader experience exhibits the strongest relationship with project success, followed by organizational experience. Further, in contrast to prior-related research on work teams, we find no relationship between individual experience or team familiarity and project success beyond that explained by team leader and organizational experience. These results suggest that a well-developed and deployed structured problem-solving process—characteristic of effective six sigma deployments—may reduce the importance of team familiarity in the context of improvement teams.  相似文献   
996.
The development in the working of markets has been an important topic in economic history for decades. The volatility of market prices is often used as an indicator of market efficiency in the broadest sense. Yet, the way in which volatility is estimated often makes it difficult to compare price volatility across regions or over time for two reasons. First, if prices are non-stationary, the variance is inflated. Second, the variance of commodity prices contains information on a number of region- and time-specific factors that are not related to market efficiency. Hence, the popular coefficient of variation and related indicators are not adequate measures of the efficiency of markets and are incomparable across regions. As a solution, we suggest using a conditional heteroscedasticity model to estimate the residual (conditional) variance of commodity prices. This measure reflects how markets react to unexpected events and can therefore be seen as a measure of market efficiency. Using this approach on grain prices from the Early Modern Pisa, Paris, Vienna, and Japan, we find that the residual price volatility had declined (and market efficiency increased) in the European markets in the late sixteenth century while it remained stable in Japan.  相似文献   
997.
Abstract

This paper presents a simple weighted goal programming model which can be used to predict the current allocation of agricultural enterprises in a particular geographical area. Moreover, it also shows how the approach proposed can be integrated into a multiobjective framework to measure the opportunity cost of maintaining the current situation in terms of several criteria relevant from a private and a public perspective. In this way, the opportunity cost of sustaining the current allocation of agricultural enterprises in the irrigated lands of Tauste (Spain) is assessed in terms of gross margin, employment, seasonal labour and water consumption.  相似文献   
998.
We analyze the role of the new goods margin in the Baltic countries’ exports and imports growth during the 1995–2008 period. Using the methodology developed in Kehoe and Ruhl (2013), we define the set of least-traded goods as those that account for the lowest 10% of total exports and imports in 1995, and then trace its growth in several markets including the Baltics’ main trade partners, the European Union and Russia. We find that, on average, by 2008 least-traded goods accounted for nearly 50% of total Baltic exports to their main trade partners. Moreover, we find that increases in the share of least-traded exports coincided with the timing of the trade liberalization reforms implemented by the Baltic countries. Least-traded imports also grew at robust rates, but their growth was lower than that of exports, accounting for slightly less than a quarter of total imports, that is, about half of the exports value. Moreover, we find that the shares of least-traded imports from the EU 15 and from Russia started diverging around the time the Baltic countries joined the EU, with the EU 15 share increasing and the Russian one declining. We also find that the Baltics’ share of least-traded exports outpaced that of other economies in Central and Eastern Europe. Finally, exports of new goods from the Baltic countries suffered noticeably during the Global Financial Crisis. After the crisis ended, the restart in new goods exports growth displayed mixed patterns.  相似文献   
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