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11.
Assessing the contribution of artisanal fisheries to food security: A bio-economic modeling approach
《Food Policy》2019
Artisanal fisheries are an important food source in many developing regions. Quantitative bio-economic models are needed that comprehensively assess artisanal fisheries’ contribution to food security. Our model combines standard resource economics theory with the literature on food systems. It explains impacts of environmental variations and market development on output, prices and ultimately food security. The application to the Senegalese purse-seine fishery reveals that total sector rents account for 2% of per capita yearly food expenditures for the coastal inhabitants. We examine the relative importance of main drivers and the vulnerability of different regions. Market development plays a crucial role: The resource is of far greater relevance for remote regions. 相似文献
12.
This article aims to understand the relation between household food security and individual undernutrition. The multitude of indicators available raises the question which aspects of food security are captured by the respective indicator. In our analysis, we first assess the relation between the dimensions of food security and households’ socioeconomic characteristics. Second, we examine whether household indicators detect undernutrition in children. Finally, we investigate the role of individual‐specific characteristics for child undernutrition. The analysis is based on a novel data set of 1,200 rural households from Cambodia and Lao PDR, which combines household‐ and individual‐level data. We capture household food security by three indicators including a dietary diversity score, a consumption behavior measure, and an experiential measure. Individual nutrition status is measured via anthropometric indicators. Our results show that different household‐level indicators capture fundamentally different aspects of food security. Moreover, household food security fails to explain stunting for children under five. Dietary diversity indicators, however, explain underweight in children to a small extent. We call for more research on intrahousehold allocation of food and stress the implications of our research for the design and targeting of food and nutrition support programs. 相似文献
13.
We investigate several previously under-documented conflicts of interest that may result in analyst optimism by utilizing two unique features of brokerage firms in China, namely, the dominant ownership of large shareholders within the brokerage firms and the mandatory disclosure of brokerage firms’ commission income derived from each mutual fund client. We show that controlling shareholders of an analyst’s brokerage-firm put pressure on the analyst to report more optimistically biased earnings forecasts and recommendations to the stocks they hold larger positions in. We also find that the magnitude of analyst optimism increases with the shareholdings of the mutual funds that contribute commission fees to the analyst’s brokerage firm. These findings remain robust after incorporating a regulation change that reduces conflicts of interest in the brokerage industry and higher dimensional fixed effects, and thus are unlikely to be driven by reverse causality or omitted variable bias. 相似文献
14.
This study examines the time‐varying performance of investment strategies following analyst recommendation revisions in the UK stock market, with specific emphasis on the impact of changing market conditions. We find a negative relationship between the recommendation performance and market conditions as measured in terms of past market return and market volatility. In particular, the upgrade (downgrade) portfolio generates significantly positive (negative) net abnormal returns in bad market conditions (e.g., the dot‐com bubble burst in 2000 and the credit crisis in 2007), but not in other periods of time. Moreover, our non‐temporal threshold regression analysis shows that the reported negative relationship disappears when market conditions become better, i.e., when the past market return (market volatility) is higher (lower) than a certain level, indicating the importance of taking non‐linearity into account in the long sample period as examined in this study. Our time‐series bootstrap simulations further confirm that the superior recommendation performance in bad market conditions is not due to random chance; analysts have certain skills in making valuable up/downward revisions in bad markets. 相似文献
15.
20世纪以来,俄罗斯经历了乌克兰危机、西方经济制裁、国际油价下跌等外部因素的冲击,经济安全遭受严重威胁,在此背景下的俄罗斯政治经济战略势必波及中俄经贸合作,进而影响丝绸之路经济带建设。本文从贸易合作和对外直接投资合作方面,基于计量模型剖析俄罗斯国家经济安全对中俄经贸合作的影响过程及关联因素。研究表明俄罗斯国家经济安全危机提升了中国在俄贸易伙伴国中的地位,促使俄与中国产能合作的意愿强烈,直接投资和产能合作逐渐成为推动中俄经贸合作向纵深发展的强劲动力;俄罗斯国家经济安全危机对中俄罗贸易有显著负向影响,中俄政治关系对贸易合作有显著正向影响。这是提高中国对俄罗斯投资、提升高新技术产品在俄罗斯进口比重的机遇期,亦是推进丝绸之路经济带的重要机遇期。经济强势崛起的俄罗斯和经济体系全面崩溃的俄罗斯对丝绸之路经济带的推进均有重要影响,在与其发展战略协作伙伴关系过程中,中国恰到好处地拿捏平衡其中的大国利益边界至关重要。 相似文献
16.
晏雷 《中小企业管理与科技》2020,(6):165-166
论文对分布式电动汽车充电桩信息安全防护技术进行研究,分析充电桩信息安全防护技术应用,注重提高防护技术应用可行性与安全性。对分布式电动汽车充电桩通行特点进行分析,探究信息安全防护方案。 相似文献
17.
《Food Policy》2020
The determinants of migration have been widely studied but research has rarely addressed the roles of food insecurity and gender in the migration decision process. To address these gaps, we examine these relationships for 135,078 individuals across 94 low- and middle-income countries. We use a series of binary-choice models with sample selection and data from the 2014–2015 waves of the Gallup World Poll Survey, which includes the first global measure of individual-level food insecurity. Results, which are robust, indicate that food insecurity is an important determinant of both migration intentions and preparations, and the probability of migration intentions increase monotonically with the severity of food insecurity, and the probability of migration preparations decrease. These relationships also differ significantly by gender and level of gross national income. Evidence suggests a need for increased coordination between the international food security and migration policy agendas. 相似文献
18.
[目的]探索叶尔羌河平原绿洲土地生态安全预警问题及其时空格局变化,旨在为叶尔羌河平原绿洲土地生态安全及可持续利用提供科学的参考依据。[方法]文章运用PSR模型构建预警指标体系,采用熵值法测算各指标权重,对2000—2016年叶尔羌河平原绿洲土地生态安全警情格局进行综合分析,并利用GIS技术分析其2000年、2005年、2010年和2016年土地生态安全空间格局变化,最后运用障碍度模型探索其障碍因子。[结果](1)2000—2016年叶尔羌河平原绿洲土地生态安全综合预警指数总体呈上升态势,生态预警状态由"较不安全"转为"临界安全",警度亦由"重警"变为"中警"。(2)从空间格局来看,空间上各县域土地生态安全水平差异明显,研究初期西部地区土地生态安全状态优于东部地区, 2016年呈现出中部高、东北—西南部低的态势。(3)近17年叶尔羌河平原绿洲各县域土地生态环境状况有所改善,安全状态经历了"极不安全—临界安全—较安全"的发展历程。(4)影响土地生态安全的主要障碍因子包括单位面积耕地农药负荷、人口密度、单位面积耕地化肥负荷、土地垦殖率、人口自然增长率和单位面积耕地地膜负荷等。[结论]研究期间叶尔羌河平原绿洲土地生态安全得到明显的提升与改善,并在良好的方向发展。 相似文献
19.
《Socio》2020
Subsidy programs are sponsored by government and international agencies to improve affordability and accessibility of food and health products for socially deprived community. Although the donors in such programs allocate substantial resources to fund subsidies, a lot of it is wasted due to the inefficiency in the system arising out of product shrinkage and misplacement. This study analyzes the impact of private participation and advanced technology like RFID adoption on the donor subsidy under target consumption level. We formulate the problem as a donor funding the subsidy program through for-profit/not-for-profit newsvendor and compare the equivalent subsidy per consumption with and without RFID. We perform numerical analysis, collecting data from the public distribution system of India, and the results indicate that, unless the for-profit firm operates under a substantially reduced level of shrinkage and misplacement, the donor should always prefer a not-for-profit firm for program implementation. We also observe that among all the scenarios, a not-for-profit firm with advanced technology like RFID requires minimum donor subsidy to generate the target expected consumption. 相似文献
20.
《Socio》2020
The Indian food program has encountered a significant shortfall in storage due to slow expansion of storage facilities in comparison with procurement. The open storage of food grains results in substantial loss and deterioration of quality. While increasing storage capacity is a viable but costly and time consuming option, the adoption of policies for peak storage reduction would go a long way towards effective food grains management. On this background, this study proposes policy adoption for peak storage reduction for effective inventory management. A dynamic simulation model was built by replicating the complex flow process and incorporating the process variability for finding the bottleneck and significant factors. It was found that steep wheat procurement is the critical bottleneck factor for peak storage requirements. Two practical and straightforward, yet effective policies are proposed from the few existing strategies for peak storage reduction owing to the constraints associated with the food program. With the actual data of the food program, reduction in peak stock was estimated for the recommended policies, including the operational cost saving in storage. The practical implications of these policies within the system were also discussed. Through peak reduction, the use of open storage can be significantly reduced, and this leads to better food grains management for effective food distribution. 相似文献