An investigation of transformation-based prediction interval for the Weibull median life

Statistical inference based on the Weibull distribution, a distribution widely used in reliability and survival analysis, is usually difficult as it often involves numerical computation and approximation. However, this distribution can be transformed to near-normality by a simple power transformation. Based on this transformation, a prediction interval (PI) for its median can be easily constructed through an inverse transformation. The procedure for selecting the best power transformation through minimizing Kullback-Leibler information is described. The property of this transformation-based PI is investigated. Simple correction factors are also proposed. It is shown that the transformation-based PI with corrections performs well, irrespective of the sample size and parameter values. Simulation results show that the new PI generally outperforms the existing PI. Numerical examples are given for illustration.     

Improved estimation of portfolio value‐at‐risk under copula models with mixed marginals

Portfolio value‐at‐risk (PVAR) is widely used in practice, but recent criticisms have focused on risks arising from biased PVAR estimates due to model specification errors and other problems. The PVAR estimation method proposed in this article combines generalized Pareto distribution tails with the empirical density function to model the marginal distributions for each asset in the portfolio, and a copula model is used to form a joint distribution from the fitted marginals. The copula–mixed distribution (CMX) approach converges in probability to the true marginal return distribution but is based on weaker assumptions that may be appropriate for the returns data found in practice. CMX is used to estimate the joint distribution of log returns for the Taiwan Stock Exchange (TSE) index and the associated futures contracts on SGX and TAIFEX. The PVAR estimates for various hedge portfolios are computed from the fitted CMX model, and backtesting diagnostics indicate that CMX outperforms the alternative PVAR estimators. © 2006 Wiley Periodicals, Inc. Jrl Fut Mark 26:997–1018, 2006     

水压作用下房屋地下室底板开裂的结构处理

地下水压力过大引起房屋地下室底板钢筋混凝土开裂,甚至被破坏,文章介绍采用钻孔桩加固技术进行结构处理,并新作防水层防水。     

中国金融业分业经营与混业经营研究

实践表明，混业经营有助于增强金融机构的国际竞争力，促进一国经济的发展，目前已成为全球金融业发展的趋势。就我国而言，从长远的角度来看，混业经营是金融业的必然选择，但短期内尚不具备过渡的条件。由于我国已加入WTO，所以目前应抓住机遇，采取相应的对策，为将来混业经营作好准备。     

科技创新与国防R&D激励——基于委托代理框架的博弈分析

国防R&D是国防科技创新的源泉.国防R & D活动存在着复杂的委托代理关系,导致分摊成本和信息租金的增加.本文用委托代理理论框架对国防R & D行为主体进行激励分析,通过构建政府与军队、军队与企业在信息不对称条件下的博弈模型,揭示国防R & D活动运行的内在机理以及投资低效的深层次原因,进而对国防R & D活动激励机制进行了针对性设计,提出了一些有意义的对策性思考.     

Financial Development and Economic Growth: Empirical Evidence from Six MENA Countries

This paper examines the causal relationship between financial development and economic growth for six Middle Eastern and North African countries (Algeria, Egypt, Israel, Morocco, Syria, and Tunisia), within a quadvariate vector autoregressive framework. We employ four different measures of financial development and apply the augmented vector autoregression vector (VAR) methodology of Toda and Yamamoto to test for Granger causality. Our empirical results strongly support the hypothesis that finance leads to growth in five out of the six countries. Only in Israel could weak support be found for causality running from economic growth to financial development but no causality in the other direction. These findings suggest the need to accelerate the financial reforms that have been launched since the mid 1980s and to improve the efficiency of these countries’ financial systems to stimulate saving/investment and, consequently, long‐term economic growth.     

Looking for contagion in currency futures markets

This article tests whether there are pure contagion effects in both conditional means and volatilities among British pound, Canadian dollar, Deutsche mark, and Swiss franc futures markets during the 1992 ERM crisis. A conditional version of international capital asset pricing model (ICAPM) in the absence of purchasing power parity (PPP) is used to control for economic fundamentals. The empirical results indicate that overall there are no mean spillovers among those futures markets, but they are detected during the crisis period. That is, past return shocks originating in any one of the four markets have no impact on the other three markets during the entire sample period, suggesting that these markets are weak‐form efficient. However, this weak‐form market efficiency fails to hold during the market turmoil, especially for British pound and Swiss franc, and the sources of contagion‐in‐mean effects are mainly due to the return shocks originating in three European currency futures markets. As for the contagion‐in‐volatility, it is detected for British pound only because its conditional volatility is influenced by the negative volatility shocks from Canadian dollar, Deutsche mark, and Swiss franc, with Deutsche mark playing the dominant role in generating these shocks. JEL Classifications: C32; F31; G12. © 2003 Wiley Periodicals, Inc. Jrl Fut Mark 23:957–988, 2003     

MANAGING VENDOR INVENTORY IN A DUAL LEVEL DISTRIBUTION SYSTEM

Collaborative arrangements among members of the supply chain have received a great deal of interest in recent years as a means of reducing costs. One such arrangement is vendor managed inventory (VMI). VMI allows the vendor to make decisions concerning the quantity and timing of deliveries to the retailer. Such an arrangement offers the potential of a more efficient supply chain by removing the negative effects of retail ordering policies. A thorough review of the literature was conducted to identify factors likely to impact the performance of a VMI partnership. Computer simulation was used to study the effects of these factors from both the vendor's and retailer's perspectives. The results lend insight into the performance of VMI and guidance for managers as to the environments in which VMI is most effective.     

人力资源资产评估的几个基本要素

常言道:“十年树木,百年树人”。无论是成材还是成才,都有相似之处,那就是先要有投入然后才有产出。其投入包括资金投入,人力投入,时间投入、精力投入等,产出都具有多样性和多效性。不管是森林资源还是人力资源,二者都是综合资源,都很难确切地定量计算其实际价值。但将资源赋予     

AN EVALUATION OF PROCESS‐ORIENTED SUPPLY CHAIN MANAGEMENT FRAMEWORKS

Supply chain management (SCM) is implemented by integrating corporate functions using business processes within and across companies. Several process‐oriented frameworks for SCM have been proposed but only two of these provide sufficient detail to enable implementation. We evaluate the Supply‐Chain Operations Reference (SCOR) framework and The Global Supply Chain Forum (GSCF) framework using four criteria and identify their relative strengths and weaknesses.