Random Weighting Estimation for Quantile Processes and Negatively Associated Samples

This article presents new theories of random weighting estimation for quantile processes and negatively associated samples. Under the condition that X ₁, X ₂,…, X _n are independent random variables with a common distribution, the consistency for random weighting estimation of quantile processes is rigorously proved. When X ₁, X ₂,…, X _n are not independent of each other, random weighting estimation of sample mean is established for negatively associated samples.     

A Bottom-Up Dynamic Model of Portfolio Credit Risk with Stochastic Intensities and Random Recoveries

In Bielecki et al. (2014a Bielecki , T. R. , Cousin , A. , Crépey , S. , Herbertsson , A. ( 2014a ). Dynamic hedging of portfolio credit risk in a markov copula model . J. Optimiz. Theor. Applic . doi: DOI 10.1007/s10957-013-0318-4 (forthcoming) .[Crossref] , [Google Scholar]), the authors introduced a Markov copula model of portfolio credit risk where pricing and hedging can be done in a sound theoretical and practical way. Further theoretical backgrounds and practical details are developed in Bielecki et al. (2014b Bielecki , T. R. , Cousin , A. , Crépey , S. , Herbertsson , A. ( 2014b ). A bottom-up dynamic model of portfolio credit risk - Part I: Markov copula perspective . In: Recent Adv. Fin. Eng. 2012 , World Scientific (preprint version available at http://dx.doi.org/10.2139/ssrn.1844574) . [Google Scholar],c) where numerical illustrations assumed deterministic intensities and constant recoveries. In the present paper, we show how to incorporate stochastic default intensities and random recoveries in the bottom-up modeling framework of Bielecki et al. (2014a Bielecki , T. R. , Cousin , A. , Crépey , S. , Herbertsson , A. ( 2014a ). Dynamic hedging of portfolio credit risk in a markov copula model . J. Optimiz. Theor. Applic . doi: DOI 10.1007/s10957-013-0318-4 (forthcoming) .[Crossref] , [Google Scholar]) while preserving numerical tractability. These two features are of primary importance for applications like CVA computations on credit derivatives (Assefa et al., 2011 Assefa , S. , Bielecki , T. R. , Crépey , S. , Jeanblanc , M. ( 2011 ). CVA computation for counterparty risk assessment in credit portfolios . In: Bielecki , T.R. , Brigo , D. , Patras , F. , Eds., Credit Risk Frontiers . Hoboken : Wiley/Bloomberg-Press . [Google Scholar]; Bielecki et al., 2012 Bielecki , T. R. , Crépey , S. , Jeanblanc , M. , Zargari , B. ( 2012 ). Valuation and Hedging of CDS counterparty exposure in a markov copula model . Int. J. Theoret. Appl. Fin. 15 ( 1 ): 1250004 .[Crossref] , [Google Scholar]), as CVA is sensitive to the stochastic nature of credit spreads and random recoveries allow to achieve satisfactory calibration even for “badly behaved” data sets. This article is thus a complement to Bielecki et al. (2014a Bielecki , T. R. , Cousin , A. , Crépey , S. , Herbertsson , A. ( 2014a ). Dynamic hedging of portfolio credit risk in a markov copula model . J. Optimiz. Theor. Applic . doi: DOI 10.1007/s10957-013-0318-4 (forthcoming) .[Crossref] , [Google Scholar]), Bielecki et al. (2014b Bielecki , T. R. , Cousin , A. , Crépey , S. , Herbertsson , A. ( 2014b ). A bottom-up dynamic model of portfolio credit risk - Part I: Markov copula perspective . In: Recent Adv. Fin. Eng. 2012 , World Scientific (preprint version available at http://dx.doi.org/10.2139/ssrn.1844574) . [Google Scholar]) and Bielecki et al. (2014c Bielecki , T. R. , Cousin , A. , Crépey , S. , Herbertsson , A. ( 2014c ). A bottom-up dynamic model of portfolio credit risk - Part II: Common-shock interpretation, calibration and hedging issues . Recent Adv. Fin. Eng. 2012 , World Scientific (preprint version available at http://dx.doi.org/10.2139/ssrn.2245130) . [Google Scholar]).     

Asymptotics for Tail Probability of Random Sums with a Heavy-Tailed Number and Dependent Increments

This article obtains the asymptotics for the tail probability of random sums, where the random number and the increments are all heavy tailed, and the increments follow a certain wide dependence structure. This dependence structure can contain some commonly used negatively dependent random variables as well as some positively dependent random variables.     

Ho-Lee利率模型下带有零息票债券的投资-消费模型

在随机利率环境下研究一类带有零息票债券的投资-消费问题,其中假设无风险利率是服从Ho-Lee利率模型的随机过程,且金融市场由一种无风险资产、一种风险资产和一种零息票债券所构成。投资人希望选择一种最优投资-消费策略来最大化其有限时间段内终端财富和累积消费的期望效用。文章应用动态规划原理和变量替换方法得到了幂效用和对数效用下最优投资-消费策略的显示解。算例分析演示了最优投资-消费策略随市场参数的变化而变化的动态行为,并给出了一些经济学涵义。     

A Nonstationary Cylinder–Based Model Describing Group Dispersal in a Fragmented Habitat

□ A doubly nonstationary cylinder-based model is built to describe the dispersal of a population from a point source. In this model, each cylinder represents a fraction of the population, i.e., a group. Two contexts are considered: The dispersal can occur in a uniform habitat or in a fragmented habitat described by a conditional Boolean model. After the construction of the models, we investigate their properties: the first and second order moments, the probability that the population vanishes, and the distribution of the spatial extent of the population.     

公共事业投资主体多元化中的政府作为

相对于经济发展和结构调整而言,公共事业的改革则有些滞后.随着经济的发展,政府公共事务管理中的种种矛盾不断浮现.尤其是投资主体还没有实现多元化,基础建设和经营资金极度短缺,为此,政府应采取一系列措施,放宽市场准入,支持民间资本和外来资本进入公共事业,积极推进投资主体由国家包办向多元化投资转变,逐步形成多元化的社会资金筹措机制.     

石里克伦理观与功利主义伦理思想的比较

本文将逻辑实证主义哲学家石里克伦理学与功利主义伦理学从产生背景、基本理论、利己与利他的关系和研究方法等方面作了比较研究.认为石里克的伦理学受到功利主义影响,具有功利主义倾向,但产生于不同社会历史背景下的两种伦学反映着各自社会经济关系,因而显示出不同的特点;在同是把快乐论作为道德标准的前提下,功利主义凸显个人利益的最大化,而石里克强调社会利益主体的快乐;边沁、密尔始终无法圆满解决利己与利他的矛盾,而石里克较好地处理了"求快乐"与"利他"的关系;石里克采取的心理学的分析方法,比功利主义具有说服力.     

大学生就业决定因素分析——基于多层模型的方法

本文利用山东2007届高校毕业生就业调查数据,建立多层交叉随机效应模型,检验了个体、专业和学校等多层变量对大学生就业的影响。结果发现,初次就业概率在学校和专业之间存在显著差异,且学校因素对就业的作用大于专业,但学校与专业对就业的交互作用不显著。就业能力以及与专业相关的实习经历对就业具有显著的正向作用。因此,大学生就业政策的重点是提高教育质量和突出专业特色,提升就业能力,完善就业导向的实习指导和服务。     

农村妇女对子女的效用预期与其男孩偏好的关系

文章利用中国人民大学2010年相关调查数据从经济、照料和文化三个方面分析了我国农村地区妇女对孩子未来效用的总体预期和分性别预期,以及这种预期效用的性别差异与人们的强性别偏好之间的关系,并得出以下结论:随着经济社会的发展和人口流动的频繁,人们目前对子代的养老效用预期在经济和居住方面已经很低,但在生病照料和赡养、传宗接代方面期望依然很高;人们对男孩和女孩的预期各有侧重,依然体现了传统的"男主外,女主内"的性别认知;人们对孩子效用预期的性别差异与人们的性别偏好呈显著正相关,尤其体现在老年照料、赡养责任和传宗接代等方面,代际经济支持已经不再是影响人们男孩偏好的重要原因。     

A statistical analysis of the screening measure of multiple recursive random number generators of orders one and two

This paper presents the results of a comprehensive empirical analysis of the screening measure of multiple recursive generators (MRGs) of orders one and two. Two kinds of screening measures are distinguished: spectral test and lattice test. With regard to these screening measures, two exhaustive searches of the twenty best MRGs of orders one and two are conducted. Some empirical comparisons reveal that the screening procedure with maximum spectral value criterion is preferred in terms of efficiency and thus, is a good way of obtaining ideal MRGs of higher orders. Several extensively tested second-order MRGs are also presented and are therefore recommended.