Improved model selection criteria for SETAR time series models

The purpose of this paper is threefold. First, we obtain the asymptotic properties of the modified model selection criteria proposed by Hurvich et al. (1990. Improved estimators of Kullback-Leibler information for autoregressive model selection in small samples. Biometrika 77, 709–719) for autoregressive models. Second, we provide some highlights on the better performance of this modified criteria. Third, we extend the modification introduced by these authors to model selection criteria commonly used in the class of self-exciting threshold autoregressive (SETAR) time series models. We show the improvements of the modified criteria in their finite sample performance. In particular, for small and medium sample size the frequency of selecting the true model improves for the consistent criteria and the root mean square error (RMSE) of prediction improves for the efficient criteria. These results are illustrated via simulation with SETAR models in which we assume that the threshold and the parameters are unknown.     

基于SVM的综合实力评估系统研究

简略介绍了支持向量机的基本思想 ,研究其在综合评价中的应用。分析了对大学进行实力评估的过程 ,建立基于SVM的评价系统。比较新评价系统和采用其他方法如PCA (PrincipalComponentAnalysis主元分析 ) ,Fisher等建立的评价系统所分别取得的拟合效果。结果表明 :采用支持向量机设计的评价系统思路清晰 ,操作简单并且能取得更为理想的评估结果。     

国际基督教工会联合会与早期欧洲一体化

第二次世界大战后 ,作为欧洲压力集团之一的基督教工会通过其国际组织———国际基督教工会联合会 ,以个人活动和参与欧洲机构正式协商机制的方式 ,试图在欧洲早期一体化进程中维护基督教工会和工人的权利及利益。该组织的活动虽然取得了一定成就 ,但从总体上讲 ,其对欧洲经济政治一体化的影响仍然十分有限     

Applicability of a Neuroprobabilistic Integral Risk Index for the Environmental Management of Polluted Areas: A Case Study

Recently, we developed a GIS-Integrated Integral Risk Index (IRI) to assess human health risks in areas with presence of environmental pollutants. Contaminants were previously ranked by applying a self-organizing map (SOM) to their characteristics of persistence, bioaccumulation, and toxicity in order to obtain the Hazard Index (HI). In the present study, the original IRI was substantially improved by allowing the entrance of probabilistic data. A neuroprobabilistic HI was developed by combining SOM and Monte Carlo analysis. In general terms, the deterministic and probabilistic HIs followed a similar pattern: polychlorinated biphenyls (PCBs) and light polycyclic aromatic hydrocarbons (PAHs) were the pollutants showing the highest and lowest values of HI, respectively. However, the bioaccumulation value of heavy metals notably increased after considering a probability density function to explain the bioaccumulation factor. To check its applicability, a case study was investigated. The probabilistic integral risk was calculated in the chemical/petrochemical industrial area of Tarragona (Catalonia, Spain), where an environmental program has been carried out since 2002. The risk change between 2002 and 2005 was evaluated on the basis of probabilistic data of the levels of various pollutants in soils. The results indicated that the risk of the chemicals under study did not follow a homogeneous tendency. However, the current levels of pollution do not mean a relevant source of health risks for the local population. Moreover, the neuroprobabilistic HI seems to be an adequate tool to be taken into account in risk assessment processes.     

地方政府土地管理模式更新——农民参与的视角

土地可持续发展是科学发展观的一项重要内容.作为与土地有着最为直接利益关系的农民,其参与土地管理决策不仅合情合理,而且对于维护自身利益和土地可持续发展具有双重意义.然而,当前地方政府土地管理模式中却存在着农民参与有效性不高的问题,这既损害了农民的合法权益,也对土地可持续发展造成负面影响.这一问题的解决需要地方政府进行土地管理模式的更新,即通过制度创新吸纳农民参与到土地管理决策中来.     

Risk,trust and knowledge networks in farmers’ learning

This study reports on New Zealand dairy farmers’ access to and use of information as mediated through conditions of risk and trust within the context of their interpersonal social networks. We located participants’ reports of their information use within their perceived environments of trust and risk, following Giddens's [1990. The consequences of modernity. Polity Press, Stanford, CA] typology of trust and risk in pre-modernity and modernity. The research participants were constant users of interpersonal and print information from numerous sources, and monitored their incoming data in the light of strategic needs, reflecting their roles as both farming practitioners and business owners. Socio-spatial knowledge networks (SSKNs) combine individuals’ explanatory cognitive models of information acquisition and use with a micro-geographical analysis of their interpersonal networks. The participants showed characteristics of pre-modern, modern and even post-modern society in respect of their use of complex interactional forms, as well as a blending of individualistic and communitarian practices and concerns in their professional and personal lives.     

矩阵方程XA＝B的亚（半）正定自共轭四元数矩阵解

给出了四元数体Ｑ上ｎ×ｎ分块矩阵为亚（半）正定自共轭矩阵的一个充要条件，进而给出了Ｑ上矩阵方程ＸＡｎｍ＝Ｂｎｍ有亚（半）正定自共轭四元数矩阵解的充要条件及解集合的显式表示，从而推广改进了数城上线性方程组的反问题及矩阵反问题的相应结果．     

基于平衡计分卡的政府传统行政模式的转型

以传统政府模式转型成“企业化政府”模式为典型,把已经在企业内部取得瞩目成就的平衡计分卡管理模式引入“企业化政府”管理模式,增强政府改革的可行性和有效性。     

中小企业发展与融资体系的构建

中小企业在其不同的发展阶段面临着不同的融资需求。文章以金融支持为主线,先从宏观层面上考察了企业融资结构分别对宏观经济波动和企业融资体系的影响,再从微观角度出发,试图在对中小企业各发展过程中融资行为、融资约束、融资结构等的分析中探求其“融资难”之所在。最后再依据我国的现实国情,并结合发达国家先进经验,探讨我国中小企业融资体系的构建。     

平教会定县实验中的农村卫生工作之考察

中华平民教育促进会定县实验区在二十世纪三十年代创立了一套由村保健员、乡保健所、县保健院组成的三级卫生保健网,并在学校卫生、妇婴保健、传染病预防和疾病治疗等方面做出了显著的成绩,在当时产生了广泛的影响,对我们今天来说仍值得借鉴。