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981.
Most of the existing pricing models of variance derivative products assume continuous sampling of the realized variance processes, though actual contractual specifications compute the realized variance based on sampling at discrete times. We present a general analytic approach for pricing discretely sampled generalized variance swaps under the stochastic volatility models with simultaneous jumps in the asset price and variance processes. The resulting pricing formula of the gamma swap is in closed form while those of the corridor variance swaps and conditional variance swaps take the form of one‐dimensional Fourier integrals. We also verify through analytic calculations the convergence of the asymptotic limit of the pricing formulas of the discretely sampled generalized variance swaps under vanishing sampling interval to the analytic pricing formulas of the continuously sampled counterparts. The proposed methodology can be applied to any affine model and other higher moments swaps as well. We examine the exposure to convexity (volatility of variance) and skew (correlation between the equity returns and variance process) of these discretely sampled generalized variance swaps. We explore the impact on the fair strike prices of these exotic variance swaps with respect to different sets of parameter values, like varying sampling frequencies, jump intensity, and width of the monitoring corridor.  相似文献   
982.
This study examines health inspection data from casual dining restaurants and compares differences of food code violations between ethnic and nonethnic restaurants. A total of 7,415 violations were retrieved from the restaurant inspection reports of 769 restaurants. Ethnic restaurants have more violations than nonethnic restaurant in categories related to food time/temperature violations, cross contamination, and food condition/surface/labels. Nonethnic and chain restaurants had fewer behavioral violations than ethnic and independently operated restaurants. Ethnic restaurants were 1.74 times more likely than nonethnic restaurants to have critical violations. Meanwhile, independent restaurants were 1.64 times more likely than chain restaurants to have critical violations.  相似文献   
983.
根据2011-2014年科技部《国家重点科技基础条件资源调查表》以及国家统计年鉴数据,首先,使用赫芬达尔指数定量描述了利用国家重点科技资源进行创新活动的非均衡性。其次,使用网络DEA方法,实证分析了2012-2014年中国(内地)各省份国家重点科技资源对区域创新发展的支撑作用。研究表明,国家重点科技资源对区域创新发展的支撑作用不仅取决于资源创新生产阶段,而且受制于重点科技资源支持下的区域创新发展阶段。重点科技资源的支撑作用还有较大提升空间,70%的省份创新成果转化能力有待提高,且大部分省份的国家重点科技资源未实现优化配置。此外,全国及东部、中部和西部国家重点科技资源对区域创新发展的支撑效率不存在绝对收敛趋势。  相似文献   
984.
The endogenous grid method (EGM) significantly speeds up the solution of stochastic dynamic programming problems by simplifying or completely eliminating root-finding. We propose a general and parsimonious EGM extended to handle (1) multiple continuous states and choices, (2) multiple occasionally binding constraints, and (3) non-convexities such as discrete choices. Our method enjoys the speed gains of the original one-dimensional EGM, while avoiding expensive interpolation on multi-dimensional irregular endogenous grids. We explicitly define a broad class of models for which our solution method is applicable, and illustrate its speed and accuracy using a consumption–saving model with both liquid assets and illiquid pension assets and a discrete retirement choice.  相似文献   
985.
随着信息技术的发展,网络教学作为一种新型的辅助教学手段是当前教学改革的研究热点,也是教育信息化、校园数字化建设的必然趋势。文章在分析营养配餐类课程开设背景的基础上,介绍了营养配餐网络教学平台的构建理念、构成及实践应用。实践证明,网络教学平台辅助课堂教学能更有效地提高教学质量。  相似文献   
986.
《Research in Economics》2014,68(2):95-111
This paper proposes a symmetry-breaking model of trade with a finite number of identical countries and a continuum of tradeable consumption goods, which differ in their dependence on nontradeable intermediate inputs, “producer services”. Productivity of each country is endogenous due to country-specific external economies of scale in its service sector. It is shown that, in any stable equilibrium, the countries sort themselves into specializing in different sets of tradeable goods and that a strict ranking of countries in per capita income, TFP, the service sector share, and the capital–labor ratio emerge endogenously. Furthermore, the distribution of country shares, the Lorenz curve, is unique and analytically solvable in the limit, as the number of countries grows unbounded. Using this limit as an approximation allows us to study what determines the shape of distribution, perform various comparative statics and to evaluate the welfare effects of trade. In doing so, this paper extends the analysis of Matsuyama (Econometrica, 81:5 (September 2013), 2009–2031) for more general and flexible forms of scale economies. It turns out that the technique introduced in Matsuyama (Econometrica, 81:5 (September 2013), 2009–2031) is useful for the equilibrium characterization in this general case as well. Although some results of comparative statics and on welfare inevitably need to be modified, they change in ways that illuminate the underlying mechanism of symmetry-breaking.  相似文献   
987.
裴志 《价值工程》2014,(8):128-130
价值工程作为一种将功能与成本、技术与经济相结合而进行技术经济评价的方法,又称为价值分析。本文通过结合地下管线探测项目的具体实例,探讨了在具体的施工过程中,为了在降低工程成本的同时能够有效的保证施工工程的质量和进度,如何采用价值工程的方法选择以及优化施工组织设计的方案。实践证明,在施工项目中应用价值工程的方法不仅能够完善施工方案,还能有效确保施工进度并且能够有效提高利润,最重要的是还能够很好的保证施工质量。  相似文献   
988.
This work assesses the causal impact of the EU trade preferences granted to the Southern Mediterranean Countries (SMCs) in agriculture and fishery products over the period 2004–2014. It overcomes some of the weaknesses of previous assessments and presents several methodological improvements. Firstly, it relies on a continuous treatment – i.e. preferential margins – to capture the ‘average treatment effect’ of trade preferences, rather than on a binary treatment based on dummy variables. Secondly, it uses highly disaggregated data at sectoral level in order to evaluate properly the preferential treatment. Thirdly, it applies a non-parametric matching technique for continuous treatment – specifically, a generalized propensity score matching. The results show, on the one hand, that the impact of the EU preferences is positive and significant on SMCs trade and is better evaluated using impact evaluation techniques. On the other hand, they demonstrate that the relationship between preferences and trade flows is asymmetric and warn against the risk of providing too much of a good thing. These results raise important issues for policy-making. First, they demonstrate that raising the level of preferences is not the solution to foster the SMCs trade towards EU. Second, that the policy-makers should put more emphasis on complementary factors other than trade barriers.  相似文献   
989.
In this paper, we examine the currency market linkages of South Asian member countries using daily data from 6 January 2004 to 31st March 2016. Time invariant and varying Copula GARCH models show that South Asian countries, except for India and Nepal/Bhutan, have low levels of currency market linkages which can be ascribed to poor levels of intra-regional trade intensity and portfolio flows. We reconfirm the copula results through Diebold and Yilmaz methodology and document that currency market connectedness is very limited in the South Asian region. The trends of the fundamental determinants of currency co-movements for the South Asian member countries were compared with its neighbouring regional economic bloc in Asia which has a much longer history and a wider membership base i.e ASEAN + 6. From a comparative analysis, it was found that South Asia member states have to work on their governance parameters, improve on their trade linkages and trade tariffs and work towards greater degree of capital account convertibility with adequate safeguards to achieve higher levels of currency market linkages.  相似文献   
990.
现代信息服务业是国民经济和现代服务业的重要组成部分。加快现代信息服务业发展是经济社会转型升级的必然选择。文章在分析我国现代信息服务业发展现状及问题的基础上,探讨了经济社会转型升级需要现代信息服务业推动,并从科学制定发展规划、加强人才培育与引进、优化产业结构等方面提出了加快现代信息服务业发展的对策。  相似文献   
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