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91.
Prior literature indicates that quadratic models and the Black–Karasinski model are very promising for CDS pricing. This paper extends these models and the Black [J. Finance 1995, 50, 1371–1376] model for pricing sovereign CDS’s. For all 10 sovereigns in the sample quadratic models best fit CDS spreads in-sample, and a four factor quadratic model can account for the joint effects on CDS spreads of default risk, default loss risk and liquidity risk with no restriction to factors correlation. Liquidity risk appears to affect sovereign CDS spreads. However, quadratic models tend to over-fit some CDS maturities at the expense of other maturities, while the BK model is particularly immune from this tendency. The Black model seems preferable because its out-of-sample performance in the time series dimension is the best.  相似文献   
92.
This article makes use of hourly crime counts to model the relationship between events that take place at the Prudential Center in Newark, NJ and robberies, an arena that has caused local controversy regarding the costs and benefits of hosting such an entertainment venue. Results from the econometric model suggest that the NHL’s New Jersey Devils ice hockey games, concerts, and Disney-themed events are all associated with increases in robbery, while various other event categories such as the NBA basketball games played by the Nets and boxing, and mixed martial arts (MMA) matches are not associated with an increase. These findings support two complementary ecological theories of crime that focus on how events provide additional opportunities for crime by increasing the associated benefits while simultaneously decreasing the cost for economically motivated offenders to take advantage of.  相似文献   
93.
《The World Economy》2018,41(9):2349-2373
As the formal process of Brexit has already started, there is much uncertainty about Brexit's impacts on Britain's social, political and economic future. This paper examines the economic impact. After briefly discussing some significant EU treaties that serve as the background materials, it presents the key arguments advocated by the leave and remain camps. The economic impact depends critically on the negotiation outcomes. Aside from the debate on the divorce costs, there are numerous issues that must be negotiated, such as immigration, trade in goods, services, agriculture, fisheries and financial regulations. We discuss various scenarios of possible new trade regimes, resulting in different impacts on the UK economy. With each side having its bargaining chips to play, the trade‐offs between “give and take” in the negotiation game are analysed. Considering various strategic options, this paper urges rationality and cooperation, especially weighing both sides’ entwined economic interests, in addition to their mutual security, defence, environmental and world concerns. The potential gains and losses in the event where the UK contemplates new trade arrangements with the non‐EU countries are analysed in the Appendix .  相似文献   
94.
Innovative entrepreneurship is an essential but often missing outcome of poverty alleviation efforts. This qualitative study set in rural Ghana explores the occupational identity of entrepreneurs, the institutions that shape it in isolated “island networks”, and how it influences entrepreneurs' practices and decisions. We find that the institutional forces of “collectivism” and “fatalism” feature prominently. Being an entrepreneur in such settings means being a mentor, market link, and community safety net, and the types of opportunities entrepreneurs pursue are largely seen as pre-destined and inherited rather than individually chosen. As a result, the pursuit of innovative opportunities may be significantly limited.  相似文献   
95.
刘艳 《科技和产业》2018,(11):49-52
Catapults(弹射中心)作为一种新型研发组织形式,在英国创新发展战略的实施中扮演着重要角色。精准的组织功能定位、高效的组织管理运作模式和紧密的网络化组织关系,是Catapults组织管理模式创新的重要三大重要内容。为我国新型研发机构的培育和发展提供了良好的参考样本。  相似文献   
96.
The “industry nurturing agriculture” reforms and World Trade Organization accession led to dramatic growth in public expenditure and international trade in China’s agricultural sector. This article aims to estimate the effects of public expenditure and trade on agricultural productivity in China for 2004–2015. A semi-parametric production function with shape constraints is introduced to derive more accurate productivity before the productivity determinants are analyzed with an emphasis on public expenditure and trade. The empirical result shows that public expenditure and exports can effectively improve agricultural productivity, while imports have no significant effects. Policy implications are discussed in the context of supply-side reforms.  相似文献   
97.
为系统探讨陕西省水文化遗产的保护与利用,丰富相关理论与实践,按照理论分析-现状分析-对策研究的思路,从陕西省水文化遗产内涵与价值分析出发,对陕西省水文化遗产构成类型进行梳理,指出陕西省水文化遗产历史深厚、类型多样、地域特色明显,河流、水利工程等资源等级较高,诗词、碑刻、民俗等资源存世量大。分析当前在认识理念、管理体制、保护经费等方面存在的问题,提出陕西省水文化遗产建设应着眼于以生态系统修复、人文系统重构、价值系统重塑、产业系统创新、管理系统再造的"全域统筹、理念重构"和基于遗址遗迹型、工程功能型和非物质文化型遗址功能与特征的"分类保护、层级联动"两大核心策略,兼顾"点、线、面"3个空间要素,构建陕西省水文化"点状布局、线状串联、流域覆盖"大遗产格局。  相似文献   
98.
为了掌握福鼎市桐江溪卤乙酸(HAAs)的含量、时空分布规律及其来源,对水体中HAAs化合物进行取样调查。根据桐江溪水文情势及沿岸特点设置10个取样点,于2017年12月及2018年7月按照涨潮、退潮情况分别对水样进行采集,检测HAAs分布情况,同时将卤乙酸(HAAs)与水质特性、涨退潮进行了相关性分析。研究发现,HAAs是普遍存在于桐江溪中的污染物质。其中,一氯乙酸(MCAA)、二氯乙酸(DCAA)、三氯乙酸(TCAA)、一溴乙酸(MBAA)、二溴乙酸(DBAA)等5种卤乙酸(HAA_5)质量浓度为0.44~3.39μg/L;一氯乙酸(MCAA)、二氯乙酸(DCAA)、三氯乙酸(TCAA)、一溴乙酸(MBAA)、二溴乙酸(DBAA)、三溴乙酸(TBAA)、一溴一氯乙酸(BCAA)、一溴二氯乙酸(BDCAA)、二溴一氯乙酸(CBDAA)等9种卤乙酸(HAA_9)质量浓度为0.83~56.15μg/L。桐江溪中HAAs主要为DCAA,TCAA,TBAA 3种,其中DCAA为制药厂及医院排水导致,主要分布在下游;TCAA主要来源于河段上游的农业生产活动;TBAA为上游沸石矿尾矿库受雨水冲刷而流入的Br~-所生成,主要分布于河流中下段。相关性分析结果表明,温度与HAA_5,HAA_9质量浓度呈现正相关,pH值与HAA_5,HAA_9质量浓度呈现负相关;TCAA质量浓度于相同季节不同潮汐及不同季节相同潮汐时均呈现上游高于下游的现象,其他HAAs均不因涨潮、退潮的差异造成质量浓度分布的变化。掌握桐江溪HAAs的含量、时空分布规律及来源,探讨其与水质的相关性,对于净水工艺选择、水厂出水HAAs含量的溯源分析、水体环境风险评估以及研究水生生物体内HAAs的累积效应等有重要意义。  相似文献   
99.
生态山岳的旅游健康发展程度对山地旅游资源的可持续利用具有重要的影响。采用层次分析法和熵权法对2018年西北地区的华山、麦积山和天山天池的旅游生态健康进行了分析。结果表明:三大山岳景区旅游健康发展均处于健康状态;在资源健康方面,天山天池表现为非常健康,华山和麦积山处于健康等级;在环境健康方面,麦积山处于非常健康,华山和天山天池处于健康等级;在经济健康和旅游社会方面,三大景区均表现为健康。  相似文献   
100.
We investigate the role of contract volition and motives for accepting temporary employment in the relationship between precariousness of life and negative psychological symptoms in a sample of 275 Italian temps. Results suggest that the negative effect of contract volition on negative psychological symptoms is partially mediated by precariousness of life. A moderated mediation model shows that specific motives moderate the negative effects of contract volition on precariousness of life, so that when contract volition is higher, workers with weaker motives feel less precarious. This study broadens our understanding of temporary employment outcomes by showing that the negative consequences of precariousness of life seem to be less troublesome among temporary workers with higher contract volition and lower motivation. © 2018 ASAC. Published by John Wiley & Sons, Ltd.  相似文献   
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