Dynamic Pricing to Minimize Maximum Regret

We consider a dynamic pricing problem that involves selling a given inventory of a single product over a short, two‐period selling season. There is insufficient time to replenish inventory during this season, hence sales are made entirely from inventory. The demand for the product is a stochastic, nonincreasing function of price. We assume interval uncertainty for demand, that is, knowledge of upper and lower bounds but not a probability distribution, with no correlation between the two periods. We minimize the maximum total regret over the two periods that results from the pricing decisions. We consider a dynamic model where the decision maker chooses the price for each period contingent on the remaining inventory at the beginning of the period, and a static model where the decision maker chooses the prices for both periods at the beginning of the first period. Both models can be solved by a polynomial time algorithm that solves systems of linear inequalities. Our computational study demonstrates that the prices generated by both our models are insensitive to errors in estimating the demand intervals. Our dynamic model outperforms our static model and two classical approaches that do not use demand probability distributions, when evaluated by maximum regret, average relative regret, variability, and risk measures. Further, our dynamic model generates a total expected revenue which closely approximates that of a maximum expected revenue approach which requires demand probability distributions.     

信托财产权的法理学研究

信托是一种财产关系,以财产为中心,以财产权为具体内容。信托整个的精髓就在于它移转并分割所有权的设计。深入分析信托财产权产生的原因、存在的基础和信托财产权构造的哲学基础和经济基础等,有助于我们理解信托特定的财产权利关系。     

美国的消费信贷和金融工具创新——简介美国的支付卡行业

居民的高消费是当代美国经济的突出特征,这是以发达的金融消费信贷网络体系为背景的。本文介绍了美国支付卡行业的诞生与成长过程。揭示了国民消费观念与制度创新和技术进步的密切相关性,进而给出了我国消费信贷的起步与发展的应对之策。     

处在"战略十字路口"的美国如何面对中国--对美国《四年防务评估报告》热评论的冷思考

在新的《四年防务评估报告》中,布什政府把中国定位为处在“战略十字路口”的国家,而这一定位恰使世界看到美国才真正处在一个“战略十字路口”。面对中国等发展中国家的发展,美国能否调整自己的心态,“以相容超越零和”,是世界能否和平稳定的关键。     

新世纪以来中国农村扶贫开发面临的困境

我国农村扶贫开发的成绩是骄人的,改革开放以来农村扶贫取得了举世公认的成果,贫困人口大规模缩减,生活水平大幅度提高,贫困地区的基础设施建设成效显著.但由于环境的制约和经济社会发展不平衡,我国农村扶贫开发仍然面临着严峻的挑战.本文着眼于新世纪以来农村扶贫面临的困境,并进行较深入的剖析.     

抗战前后刘湘的政治抉择新论

对刘湘的评价长期以抗日战争为分野,形成二元对立的状态:抗战之前刘湘被视为“反动军阀”,之后则被誉为抗日“爱国将领”的模范式人物.其实,刘湘一生的政治选择具有内在的一致性而非简单的“转变”:不管是在军阀混战还是在抗战时期,其身上均伴随有四川军阀“统一全川”和“川人治川”的观念,极力维护自己在四川的统治地位,即便是对抗日问题的选择,同样是对于自身利益和国家利益的综合考量,即在“救国”的目的之外,还希望通过抗日来抵制蒋介石对四川的控制.而当时国家主义与地方主义升降变迁所造成的国家局势变化,是刘湘选择出川抗日背后重要的时代原因.     

“文人”概念起源考释

"文人"是一个发展性概念,其远源是"士"。在西周到春秋初叶,"文人"指有文德的人。春秋战国之际,"文士"崛起。到东汉时,"文人"等同"文士",指那些有较高文化水平和代表社会道义的知识阶层的成员。     

An Integrated Risk Assessment Model of Township‐Scaled Land Subsidence Based on an Evidential Reasoning Algorithm and Fuzzy Set Theory

Land subsidence risk assessment (LSRA) is a multi‐attribute decision analysis (MADA) problem and is often characterized by both quantitative and qualitative attributes with various types of uncertainty. Therefore, the problem needs to be modeled and analyzed using methods that can handle uncertainty. In this article, we propose an integrated assessment model based on the evidential reasoning (ER) algorithm and fuzzy set theory. The assessment model is structured as a hierarchical framework that regards land subsidence risk as a composite of two key factors: hazard and vulnerability. These factors can be described by a set of basic indicators defined by assessment grades with attributes for transforming both numerical data and subjective judgments into a belief structure. The factor‐level attributes of hazard and vulnerability are combined using the ER algorithm, which is based on the information from a belief structure calculated by the Dempster‐Shafer (D‐S) theory, and a distributed fuzzy belief structure calculated by fuzzy set theory. The results from the combined algorithms yield distributed assessment grade matrices. The application of the model to the Xixi‐Chengnan area, China, illustrates its usefulness and validity for LSRA. The model utilizes a combination of all types of evidence, including all assessment information—quantitative or qualitative, complete or incomplete, and precise or imprecise—to provide assessment grades that define risk assessment on the basis of hazard and vulnerability. The results will enable risk managers to apply different risk prevention measures and mitigation planning based on the calculated risk states.     

固定效应部分线性变系数面板模型的快速有效估计

本文将最小二乘支持向量机(LSSVM) 和二次推断函数法(QIF) 相结合，为个体内具有相关结构的固定效应部分线性变系数面板模型提供了一种新的快速估计方法；在一定的正则条件下，论证了参数估计量的渐近正态性和非参数估计量的收敛速度；采用Monte Carlo模拟考察了估计方法在有限样本下的表现并将估计技术应用于现实数据分析。该方法不仅保证了估计的有效性和统计推断力，而且程序运行速度得到较大幅度提升。