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991.
Statistical issues arising in modelling univariate extremes of a random sample have been successfully used in the most diverse fields, such as biometrics, finance, insurance and risk theory. Statistics of univariate extremes (SUE), the subject to be dealt with in this review paper, has recently faced a huge development, partially because rare events can have catastrophic consequences for human activities, through their impact on the natural and constructed environments. In the last decades, there has been a shift from the area of parametric SUE, based on probabilistic asymptotic results in extreme value theory, towards semi‐parametric approaches. After a brief reference to Gumbel's block methodology and more recent improvements in the parametric framework, we present an overview of the developments on the estimation of parameters of extreme events and on the testing of extreme value conditions under a semi‐parametric framework. We further discuss a few challenging topics in the area of SUE. © 2014 The Authors. International Statistical Review © 2014 International Statistical Institute  相似文献   
992.
目前国内学者对预算过程的研究还没有足够的重视。中美两国的预算过程有着很大的差异,立法部门预算过程的差异尤为明显。通过对美国预算过程的分析,可以发现立法部门在美国预算过程中处于主导地位,预算过程的运行受到大量制度安排的控制。结合国情,我国应该通过制度建设与机构改革逐步完善立法部门的预算监控职能,并通过程序控制与法律手段保证立法部门的预算意志得以执行。  相似文献   
993.
张朝  雷同飞 《价值工程》2015,34(9):49-51
本文主要研究了一种基于温差发电的混合动力自行车,并就其改装和发动机尾气余热利用的系统优化设计进行了集中分析,最终得出了相关结论。  相似文献   
994.
The financial system is currently undergoing a revolution brought about by e-finance, digital convergence, new market entrants and government-encouraged competition. New market entrants such as Apple, Alibaba, Facebook and Google come from industries such as IT, retail, social media and telecoms, and, therefore, do not fit comfortably within traditional financial institutional structures. A functional perspective might provide more practical insights into this revolution; however, the functional perspective has had a limited impact. This paper will investigate the benefits and limitations of financial functional analysis; probe the underpinning principles of sociology’s structural functional analysis; revisit Merton and Bodie’s (1995) six core financial functions in relation to new entrants in the financial landscape; and, finally, argue that in the new financial environment, functional analysis provides a more coherent and explanatory framework of the financial system for students and practitioners alike.  相似文献   
995.
We demonstrate how it is possible to generate value for an investor with a hedge attached to the buy-and-hold strategy of an S&P 500 index fund. We study the S&P 500 index portfolio (not including dividends) and the value-weighted S&P 500 index portfolio (including dividends) of the Center for Research in Securities Prices for 1967:01–2011:12, using the capacity utilization and the unemployment rates in real time to determine if a hedge position should be initiated or closed. A hedge is initiated if the capacity utilization, the unemployment rate or a combination of the two signals a contraction in the real economy. The hedge position is closed if it signals otherwise an expansion. We use utility gains (Campbell and Thompson 2008), the manipulation-proof performance measure (MPPM) statistics (Ingersoll et al. 2007) and the P-Sharpe ratio (Bailey and López de Prado 2012) to evaluate the performance of a particular hedge strategy. The empirical results show that there are infinitely many hedges that can generate positive utility gains, higher MPPM statistics and higher P-Sharpe ratios.  相似文献   
996.
Recent years have seen an explosion of activity in the field of functional data analysis (FDA), in which curves, spectra, images and so on are considered as basic functional data units. A central problem in FDA is how to fit regression models with scalar responses and functional data points as predictors. We review some of the main approaches to this problem, categorising the basic model types as linear, non‐linear and non‐parametric. We discuss publicly available software packages and illustrate some of the procedures by application to a functional magnetic resonance imaging data set.  相似文献   
997.
计量体系包括标准的建设及以技术为手段的计量管理。标准是衡量质量高低的基本依据,各项标准的实施,又要以相应的计量检测和科学的计量管理为技术手段和管理基础。企业计量体系运行的成功与否,直接关系到产品质量结果的控制。经过陕西省质量技术监督初审和2次复查考核,2008年1月份,建标申请经考核合格后获得了授权,并于2月份,压力类强检仪表也获得了对内强检资质。长庆油田分公司第二采气厂计量体系的建设与运行步入正规化、运行基本实现了专业化。  相似文献   
998.
Despite the cost and resource‐effectiveness of joint trade negotiations and complementarities between goods and services‐trade flows, more than 12% of the 132 WTO‐notified services‐trade agreements (STAs) in force until August 2015 were entered into effect sequentially to goods‐trade accords. This stylised fact motivates our study of the determinants of joint versus sequential negotiation/accession of goods and services accords, a subject hitherto unexplored in the growing literature on the determinants of STA membership. Our results suggest larger marginal effects of fundamental economic, geographic, institutional, doing business and services regulatory factors on the propensity of joint negotiation/accession compared to STA formation alone. Moreover, cultural‐distance variables are only found to affect the likelihood of joint preferential liberalisation of goods and services trade, without influencing STA‐only membership.  相似文献   
999.
失地农民再就业一直是党和政府着力解决的"三农"问题之一。从消除制度缺陷、提供培训资金支持、拓宽非农产业就业渠道、搞好就业培训等方面采取的措施尚未见到实效。失地农民再就业受到收入水平、生活成本、工作环境、技能要求、地区经济发展等因素的影响,政府应当在注重产业布局和调整的同时适度保留劳动密集型产业、加大公共财政保障力度,强化用人单位培训责任、系统设计失地农民权益保障制度等方面入手,破解失地农民"被城市化"后的再就业困境。  相似文献   
1000.
谢颖 《科技与企业》2014,(14):150-151
针对国内外电厂对缆式线型感温的设计要求,突出了线型感温探测的重要性。从光纤感温探测的原理开始,对整套系统进行了结构性研究。主要研究了系统结构、探测光缆、控制器等组件。结合拉曼散射原理,剖析温度变化引起探测光缆的吸收和反吸收效应;强调了光学感温探测系统的应用优势和安装条件等。最后结合实体项目,分析对比了传统感温电缆和光学感温探测系统在实际工程应用中的优缺点,并提出了优化方案,以提高火灾报警系统的工作效率。  相似文献   
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