A robust and efficient estimation method for nonparametric models with jump points

Nonparametric models with jump points have been considered by many researchers. However, most existing methods based on least squares or likelihood are sensitive when there are outliers or the error distribution is heavy tailed. In this article, a local piecewise-modal method is proposed to estimate the regression function with jump points in nonparametric models, and a piecewise-modal EM algorithm is introduced to estimate the proposed estimator. Under some regular conditions, the large-sample theory is established for the proposed estimators. Several simulations are presented to evaluate the performances of the proposed method, which shows that the proposed estimator is more efficient than the local piecewise-polynomial regression estimator in the presence of outliers or heavy tail error distribution. What is more, the proposed procedure is asymptotically equivalent to the local piecewise-polynomial regression estimator under the assumption that the error distribution is a Gaussian distribution. The proposed method is further illustrated via the sea-level pressures.     

Optimal financing and dividend policy with Markovian switching regimes

This work investigates an optimal financing and dividend problem for an insurer whose surplus process is modulated by an observable continuous-time and finite-state Markov chain. We assume that the insurer should never go bankrupt by issuing new equity. The goal of the insurer is to maximize the expected present value of the dividends payout minus the discounted cost of equity issuance. We obtain the optimal policies and explicit expressions for the value functions when the risk reserve process is modeled by both upward jump model and its diffusion approximation. Numerical illustrations of the sensitivities of the model parameters are provided.     

Quality self-control and co-supervision mechanism of construction agent in public investment project in China

Public investment project (PIP) plays an important role in the China economy. In order to improve the project management performance of public projects, the government is searching for a scientific system to build a construction management supervision mode. This paper introduces the policy background and connotation of Agent Construction System (ACS). As a public investment construction management model, ACS, is gradually being incorporated into the legal framework, it is necessary to improve the construction agent supervision mechanism. This article analyzes the supervision mechanism of construction agent quality management under the principle of two-stage agent mode and establishes an agent quality self-control system and a government co-supervision system. These systems take the contract management as the core and the project quality objective as the guidance. These systems also consist of a two-dimensional framework of vertical self-control and horizontal supervision, which form a quality supervision mechanism. Based on Rough Set theory, the article proposes the idea of building an agent quality self-control and government co-supervision model, and illustrates it with a flow chart for building the model, which paves the way of quantitative research for the future.     

合法性悖论:淘宝村民间团体的生存困境

大量淘宝网商在农村集聚,新兴"淘宝村"成为农村转型发展的模式之一,随之带来的是村内代表行业共同利益的民间团体不断涌现,这类新生团体的合法性建构及其面临的困境引人关注。一方面,自下而上发育的民间团体具有公众合法性能达致正常运转,却因无法获得体制合法性而陷入生存困境;另一方面,民间团体在获得体制合法性后却没有如预期般长期享受发展优势,反而动摇了先前的公众合法性,进入体制铁牢笼,同样也陷入生存困境,由此造成"合法性悖论"。公众合法性与体制合法性的冲突造成的"合法性悖论",反映了政府"体制控制"过强而民间团体自身对两类合法性的定位模糊,同时也体现了在市场转型日渐深入的背景下所凸显的"国家"与"社会"的矛盾。淘宝村社会组织的发展与"淘宝村"的未来前景息息相关,如何破解"合法性悖论",在当前背景下发挥民间团体的活力,其路径选择和发展模式也为社会治理提出了新的问题。     

Bayesian ratemaking under Dirichlet process mixtures

Experience ratemaking plays a crucial role in general insurance in determining future premiums of individuals in a portfolio by assessing observed claims from the whole portfolio. This paper investigates this problem in which claims can be modeled by certain parametric family of distributions. The Dirichlet process mixtures are employed to model the distributions of the parameters so as to make two advantages: to produce exact Bayesian experience premiums for a class of premium principles generated from generic error functions and, at the same time, provide robust and flexible ways to avoid possible bias caused by traditionally used priors such as non informative priors or conjugate priors. In this paper, the Bayesian experience ratemaking under Dirichlet process mixture models are investigated and due to the lack of analytical forms of the conditional expectations of the quantities concerned, the Gibbs sampling schemes are designed for the purpose of approximations.     

Welfare Programme Participation and the Wellbeing of Non-local Rural Migrants in Metropolitan China: A Social Exclusion Perspective

Social Indicators Research - China has seen an unprecedented increase in rural-to-urban migrants in the last three decades, and the extension of welfare programmes to these migrants has been a...     

中东剧变中的阿尔及利亚政局透视

2010年底以来,中东地区多国发生了政权更迭,阿尔及利亚一度爆发群众游行示威,但目前阿尔及利亚政局基本稳定,原因可归纳为以下四个方面:一是阿尔及利亚独立以来的长期动荡释放了民众的不满;二是布特弗利卡执政联盟仍具有较强的政治实力;三是国内的两个主要反对派因其各自的缺陷,难以获得大多数民众的支持;四是现政权与美国保持了较好的关系。然而,由于目前中东地区的局势尚在发展中,随着新因素的加入,阿尔及利亚的政局仍存在变数。     

景气指标分类方法的理论研究与实证

景气指标分类是景气预测法中至关重要的环节.在以往的文献中,一般采用一种方法对备选指标进行景气分类,但其结果还存在优化的空间.文章采用四种典型的景气指标分类方法:峰谷对应法、时差相关分析法、K-L信息量法、灰色关联度指标分类法对同样的多个指标进行分类.按照初定方案对四种方法的结果进行综合分析,对结果进行优化调整,应用实例表明:四种方法的优化调整结果比单一方法的结果更合理、更有效、更具有科学性.     

我国企业国际承包工程绩效管理机制研究

国际工程承包近年来在我国取得了飞速发展，随着全球经济一体化进一步发展、我国国力的日益增强以及中国企业管理水平的提高，中国企业在国际工程承包方面竞争力日益增强的同时，如何构建有效的绩效管理机制也成为企业必须重视的课题。结合我国企业国际工程承包的发展历史及现状，重点分析了企业在经营过程中面临的问题，进而提出构建有效的绩效管理机制的方案。     

Optimal RSUs deployment with delay bound along highways in VANET

In order to broadcast an alert message from the accident site to the control center as soon as possible, the roadside units (RSUs) act as the critical component in vehicular ad hoc networks (VANETs). It is not possible to make a pervasive RSU deployment due to the huge cost and market requirement. Hence, how to deploy a minimum number of RSUs in a given region becomes a challenge problem. In this paper, we present an analysis for the total delay of broadcasting alert messages in VANETs along highways. Based on the analysis, the relationship between optimal number of RSUs with the highway distance is given. Moreover, the experiment results verifies the delay analysis and the optimization of RSUs deployment.