A Maximum Entropy Joint Demand Estimation and Capacity Control Policy

We propose a tractable, data‐driven demand estimation procedure based on the use of maximum entropy (ME) distributions, and apply it to a stochastic capacity control problem motivated from airline revenue management. Specifically, we study the two fare class “Littlewood” problem in a setting where the firm has access to only potentially censored sales observations; this is also known as the repeated newsvendor problem. We propose a heuristic that iteratively fits an ME distribution to all observed sales data, and in each iteration selects a protection level based on the estimated distribution. When the underlying demand distribution is discrete, we show that the sequence of protection levels converges to the optimal one almost surely, and that the ME demand forecast converges to the true demand distribution for all values below the optimal protection level. That is, the proposed heuristic avoids the “spiral down” effect, making it attractive for problems of joint forecasting and revenue optimization problems in the presence of censored observations.     

城市防洪标准方案优选的最大信息熵原理与投影寻踪耦合模型

城市防洪标准方案优选是城市防洪规划的首要问题。提出用最大信息熵原理构造投影寻踪评价模型中的投影指标函数,并将该耦合模型应用于实际的城市防洪标准方案优选中。结果表明:用该耦合模型所确定的各方案投影值之间的差异明显,方法直观简便,优选结果稳健,该耦合模型适用性和可操作性强,在实际工程方案优选中具有推广应用价值。     

基于熵原理的证券投资基金绩效综合评价研究

本文通过综合考虑,构建了证券投资基金的绩效评价体系.特别针对指标权重的确定问题,提出了基于广义最大熵原理和优化理论的新赋权方法.并以此对2000年底前成立的29只积极管理的基金进行了排序分析,结果表明了该方法的合理性.     

基于最大熵分布的控制图改进与评价研究

传统的控制图多是假定质量特性参数服从正态分布,但在很多情况下正态分布的假设并不成立。本文基于最大熵分布从控制图的构建和评价两个方面分别提出对Shewhart控制图和CUSUM控制图的改进方法。首先根据"经济性"原则构建最大熵Shewhart控制图,实现对Shewhart控制图的改进;然后,提出结合最大熵分布和马尔科夫链方法的CUSUM控制图评价方法。仿真结果表明,基于最大熵分布改进后的Shewhart控制图控制性能优于改进之前的情况;而基于最大熵分布的CUSUM控制图的性能评价方法得到的结果能更符合真实的情况。在对不同偏移的监测中,最大熵Shewhart控制图更适用于分布未知的大偏移情况,而自适应CUSUM控制图对小偏移有更好地监控效果。     

最大灰信息熵路网军事交通流最大隐蔽性分配模型研究

路网军事交通流的最大隐蔽性分配问题是军事演习和战时道路交通指挥决策所必须解决的问题。本文运用系统论的思想和灰色信息熵理论,构建了基于最大灰信息熵的路网军事交通流最大隐蔽性分配模型,从而较好地解决了这一问题。此外,该模型的构建也为这一问题的进一步研究打下了良好的基础。     

考虑专家判断信息的灰色关联极大熵权重模型

本文提出了一种从关联角度出发将主观先验信息与客观信息纳入约束条件从而求解综合权重的方法。在利用灰关联深度系数对实际决策问题进行客观权重判断研究的基础之上,构建了源于专家判断信息的权重势比的主观约束条件,将主客观因素同时反映在优化模型的约束条件中,并将权重的极大熵作为目标函数,保证权重判断的可信度,从而构建了确定评价指标综合权重的极大熵优化模型。该方法克服了将主客观条件直接通过线性组合作为目标函数时,主客观参数选取导致的权重大小的不确定性,并同其他赋权方法进行案例结果比较,表明了该方法的有效性。     

基于案例学习的多层次聚类指标客观权重极大熵挖掘模型

本文针对待聚类对象的多层次聚类指标权重配置问题进行了研究。首先运用向量空间模型将聚类对象表征为包含多个层次聚类属性指标的特征空间向量并基于余弦距离测算底层属性指标的相似程度,然后根据聚类指标的层次结构以及相应各层指标的权重系数综合测算对象之间的相似程度,最后根据历史聚类案例中相同类别对象之间相似度较大,不同类别对象之间相似度较小等特点,构建了基于案例学习的多层次聚类指标客观权重极大熵挖掘模型。通过案例分析以及与其他方法的比较研究,证明了本模型的可行性与有效性,为多层次聚类指标客观赋权问题提供了一种新的研究思路。     

The Economic Circumstances Surrounding the Decision to Capitalize Brands—A Comment

The paper offers a reappraisal of the empirical study by Mather and Peasnell (1991) of 13 UK brand-capitalizing companies. It argues that the findings of this study can be questioned on a variety of grounds including: method appropriateness, indirectness, timing and data issues. Specifically, it is suggested that their use of market reaction testing on this topic fails to capture the wide variety of economic consequences that may flow from brand capitalization.     

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.     

A Novel Evolutionary Formulation of the Maximum Independent Set Problem

We introduce a novel evolutionary formulation of the problem of finding a maximum independent set of a graph. The new formulation is based on the relationship that exists between a graphs independence number and its acyclic orientations. It views such orientations as individuals and evolves them with the aid of evolutionary operators that are very heavily based on the structure of the graph and its acyclic orientations. The resulting heuristic has been tested on some of the Second DIMACS Implementation Challenge benchmark graphs, and has been found to be competitive when compared to several of the other heuristics that have also been tested on those graphs.     

用人也要追求效益最大化

干部是否用在当用之时,是检验干部工作效益高低的一个标准。针对这个问题,我们不妨先分析一下干部工作中时常出现的两种现象。现象之一,个别干部面对组织提拔使用前的谈话,没有任何的责任驱动意识,也没有任何被组织和群众信任的感动,没有荣誉感,没有任何的感恩心理。他一脸无所谓地告诉别人,这是他早该得到的,是组织对他的"补偿"。     

The Precautionary Principle Has Not Been Shown to Be Incoherent: A Reply to Peterson

In this journal, I have objected to Peterson's 2006 claim that the precautionary principle is an incoherent decision rule. I defend my objections to Peterson's recent replies, and I still claim that the precautionary principle has not been shown to be incoherent.     

Testing for Regime Switching: A Comment

An autoregressive model with Markov regime‐switching is analyzed that reflects on the properties of the quasi‐likelihood ratio test developed by Cho and White (2007). For such a model, we show that consistency of the quasi‐maximum likelihood estimator for the population parameter values, on which consistency of the test is based, does not hold. We describe a condition that ensures consistency of the estimator and discuss the consistency of the test in the absence of consistency of the estimator.     

A Comment on Second-Order Polynomial Regression Models

In a recent article, Chatterjee and Greenwood [1] addressed the problem of multicollinearity in polynomial regression models. They noted that there is a high correlation between X and X²; therefore, a second-order polynomial model suffers the consequences of collinearity. Chatterjee and Greenwood [1] suggested a method they believe will overcome the problem. The contention of the present comment is that the suggested method accomplishes nothing and, indeed, has the potential to lead the unwary researcher to the wrong inference and misinterpretation of his results.     

运用工业发展理念促进农业发展

党的十六大报告指出,统筹城乡经济社会发展,建设现代农业,是全面建设小康社会的重大任务。作为以传统农业经济为主、城乡二元经济结构突出的四川省南江县,要发展农村经济,增加农民收入,实现城乡经济协调发展,笔者认为,必须借鉴工业发展的办法,运用企业经营的理念,推进农业产业化经营,开创农业和农村工作新局面。以工业理念抓农业,必须更新发展观,按照工业化大生产的理念谋划农业。运用工业发展理念抓农业,就是按照工业化大生产的要求,跳出城市工业、农村农业的二元思维定式,用现代工业理念谋划农业发展,用工业化方式组织农业生产经营,把工业…     

基于信息熵理论的实物期权定价模型及其应用

本文结合实物期权的特点,提出了基于信息熵理论的实物期权定价模型,它根据历史信息和投资者的经验估计期权价格,避免了传统期权定价模型过多依赖于参数选择和假设条件的不足。本文还进一步探讨了该方法与传统期权定价模型间的关系,并合理的解释了企业决策中信息的重要性。最后,结合一个示例,说明了该模型在企业投资决策中的应用价值。     

Vendor Selection with Bundling: A Comment*

In a recent article by Rosenthal, Zydiak, and Chaudhry (1995), a mixed integer linear programming model was introduced to solve the vendor selection problem for the case in which the vendor can sell items individually or as part of a bundle. Each vendor offered only one type of bundle, and the buyer could purchase at most one bundle per vendor. The model employed n(m+ 1) binary variables, where n is the number of vendors and m is the number of products they sell. The existing model can lead to a purchasing paradox: it may force the buyer to pay more to receive less. We suggest a reformulation of the same problem that (i) eliminates this paradox and reveals a more cost-effective purchasing strategy; (ii) uses only n integer variables and significantly reduces the computational workload; and (iii) permits the buyer to purchase more than one bundle per vendor.