类生产函数企业价值链管理模型研究

本文从价值链的一些本质特征出发,借鉴生产函数的原理与形式,提出了一种新的价值链模型——类生产函数价值链管理,证明了类生产函数的一些重要性质,论述了此模型对企业价值链的管理与优化过程。最后进行了实例分析,分析过程及结果表明,该模型能够较好地实现价值链的优化与管理。     

一种基于区间直觉梯形模糊数偏好的大群体决策冲突测度研究

针对决策偏好为区间直觉梯形模糊数的大群体决策冲突测度问题,首先给出了两个区间直觉梯形模糊数的距离,提出了群体成员冲突函数,基于该函数对大群体成员偏好进行聚类形成若干聚集,以此为基础提出了聚集冲突测度模型并集结为群体冲突测度模型,然后应用于大群体偏好集结。最后通过一个算例对模型进行了验证。该模型便于大群体意见的分析与协调,适用于群决策支持系统,在应急决策中具有实际应用价值。     

基于协同救助的海上救助报酬合理分配方法

海上救助报酬是为鼓励人们冒险参与海上救援,由受益人给予救助人的补偿和回报,具有射幸性,奉行“无效果、无报酬”的给付原则。本文以救助方成本性和非成本性投入对救助效果的贡献为依据,首先对各方的成本性投入进行补偿;然后从资源要素的关键性和参与人的重要性两个维度对各救助方的贡献进行综合评价,并按贡献度对“剩余”部分进行二次分配,两次分配之和即为各救助方所获得的分配总额。通过运用“重购成本”和Shapley值法分别对资源要素的关键性和参与人的重要性进行客观度量,该方法可同时解决共同救助报酬的外部分配与内部分配问题,不仅避免了目前各国司法实践中按成本投入比例进行分配的不合理性,也更能体现相关国际公约和国内立法有关救助报酬分配的原则。     

基于下偏度最小化贷款组合优化模型

运用组合偏矩刻画信贷风险原理,以贷款组合下偏度最小化为目标函数,控制商业银行发生重大损失的概率;以组合风险价值VaR为约束条件,控制贷款组合的整体风险,建立基于下偏度最小化贷款组合优化模型。研究表明：下偏度不要求贷款收益服从正态分布,并能够很好地反映收益率分布的“左尾”,降低商业银行贷款组合发生重大损失的概率;同时下偏度可以真实反映贷款的本质,符合投资者的心理,并且可以反映多笔贷款之间的相关联系,解决现有模型的解析能力不足的问题。     

Customer satisfaction: Cost driver or value driver? Empirical evidence from the financial services industry

We investigate the relation between customer satisfaction, customer servicing costs, and customer value in a financial services firm. We find that customer satisfaction is positively associated with future customer servicing costs, as well as with customer value. The relation between customer satisfaction and customer value appears non-linear; higher customer satisfaction appears to have a higher return for the most profitable customer segments. Our findings indicate that customer satisfaction is a value driver; however, customer satisfaction is not cost-free and managers have to consider the costs, as well as the benefits, of increasing customer satisfaction.     

同种商品不同月份期货组合风险评价模型研究及应用

以期货合约的每一交易日的对数涨跌率来反映市场风险,借助VaR风险价值法,运用加权核估计技术(WKDE)和指数加权滑动模型(EWMA),建立了基于期货组合中持有头寸不同且可以进行风险对冲的期货组合市场风险非线性叠加评价模型,解决了同种商品、不同月份期货组合每一交易日最大损失的确定问题,并通过实证研究验证了模型的实用性.该模型的特点一是借助WKDE法预测组合中单个合约每一交易日涨跌率最大日亏损值,充分体现了期货合约涨跌率的实际走势,使VaR估计更加精确.二是通过动态迁移相关系数矩阵的计算保证了模型的精确性.采用EWMA模型预测动态变化的方差-协方差矩阵,从实证的角度得到更精准的动态迁移相关系数矩阵.三是考虑了组合中多头和空头不同头寸之间的风险对冲,避免了实际中期货组合风险的线性相加而造成放大风险或减少风险的不准确性,从而能较好地保证了模型的预测精度及准确性.四是通过基于风险非线性叠加建立的期货组合风险评价模型解决了SPAN系统中期货组合风险的线性叠加问题,从而得到更合理的组合风险预测值.     

Generic Assessment Endpoints Are Needed for Ecological Risk Assessment

This article presents arguments for the development of generic assessment endpoints for ecological risk assessment. Generic assessment endpoints would be ecological entities and attributes that are assumed to be worthy of protection in most contexts. The existence of generic assessment endpoints would neither create a requirement that they be used in every assessment nor preclude the use of other assessment endpoints. They would simply be a starting point in the process of identifying the assessment endpoints for a particular assessment. They are needed to meet legal mandates, to provide a floor for environmental degradation, to provide some consistency in environmental regulation, as exemplars for site- or project-specific assessment endpoints, to allow development of methods and models, to give risk managers the courage to act, for screening and site-independent assessments, to support environmental monitoring, to facilitate communication, and to avoid paralysis by analysis. Generic assessment endpoints should include not only a list of entities and attributes, but also explanations of each endpoint, guidance on their use and interpretation, and measures and models that could be used to estimate them.     

Risk of Extreme Events in Multiobjective Decision Trees Part 1. Severe Events

Earlier work with decision trees identified nonseparability as an obstacle to minimizing the conditional expected value, a measure of the risk of extreme events, by the well-known method of averaging out and folding back. This first of two companion papers addresses the conditional expected value that is defined as the expected outcome assuming the exceedance of a threshold β, where β is preselected by the decision maker. An approach is proposed to overcome the need to evaluate all policies in order to identify the optimal policy. The approach is based on the insight that the conditional expected value is separable into two constituent elements of risk and can thus be optimized along with other objectives, including the unconditional expected value of the outcome, by using a multiobjective decision tree. An example of sequential decision making for improving highway capacity is given.     

Failure Probability Under Parameter Uncertainty

In many problems of risk analysis, failure is equivalent to the event of a random risk factor exceeding a given threshold. Failure probabilities can be controlled if a decisionmaker is able to set the threshold at an appropriate level. This abstract situation applies, for example, to environmental risks with infrastructure controls; to supply chain risks with inventory controls; and to insurance solvency risks with capital controls. However, uncertainty around the distribution of the risk factor implies that parameter error will be present and the measures taken to control failure probabilities may not be effective. We show that parameter uncertainty increases the probability (understood as expected frequency) of failures. For a large class of loss distributions, arising from increasing transformations of location‐scale families (including the log‐normal, Weibull, and Pareto distributions), the article shows that failure probabilities can be exactly calculated, as they are independent of the true (but unknown) parameters. Hence it is possible to obtain an explicit measure of the effect of parameter uncertainty on failure probability. Failure probability can be controlled in two different ways: (1) by reducing the nominal required failure probability, depending on the size of the available data set, and (2) by modifying of the distribution itself that is used to calculate the risk control. Approach (1) corresponds to a frequentist/regulatory view of probability, while approach (2) is consistent with a Bayesian/personalistic view. We furthermore show that the two approaches are consistent in achieving the required failure probability. Finally, we briefly discuss the effects of data pooling and its systemic risk implications.     

金融网络的模型和优化

金融网络就是经济系统中资金循环,文献[1-8]研究了金融网络的模型。本文则在文献[1-8]金融网络模型的基础之上,建立了资产、负债、适度规模和价格的改进模型。这一改进模型考虑了所有经济部门的金融工具的风险、金融网络的经济资源约束、资产和负债的会计帐户约束等问题。模型的改进适用于应用。文章采用了进化规划算法,并依此进行仿真实验。