Removing the obstacles to effective strategic planning

The purpose of this article is to explore the reasons for the decline in the importance and practice of strategic planning across American industry. The article identifies numerous bureaucratic obstacles to effective planning, and suggests how these obstacles can most effectively be eliminated by attacking their root causes. The article points out the risks to the planning process that are created by attempts to eliminate these obstacles. But, it concludes that unless these obstacles are removed and the promised financial returns from strategic business planning realized, the decline of long-term strategic business planning will continue.     

有数量限制的双覆盖标准救护车选址模型

目前已经有大量的文章研究救护车选址问题,这些研究主要关注覆盖率而忽略了救护车停放点的规模问题;虽然有些文章也限制了每个救护车存放点上停放车辆的上限,但是忽略了下限,只是自然的令其为0.从规模效应来看,如果停车点停放车辆,将数量限定字一定范围内会便于管理、降低成本.所以,本文建立了有数量限制的双覆盖标准救护车选址模型,在该模型中,如果在某个救护车存放点停放救护车,则该点存放的救护车数量介于上限和下限之间,从而保证规模效应;同时给出了基于拉格朗日松弛的禁忌搜索算法和算例.模拟计算表明可以通过调整参数来达到覆盖率和停放数量限制之间的均衡.     

Computing an $$L_1$$ shortest path among splinegonal obstacles in the plane

Journal of Combinatorial Optimization - We reduce the problem of computing an $$L_1$$ shortest path between two given points s and t in the given splinegonal domain $$mathcal {S}$$ to the problem...     

Coverage, technology assessment, and the courts

Coverage decisions by third-party payers are relying more and more heavily on the conclusions of technology assessment programs about the safety and effectiveness of technologies applied in specific clinical situations. Assessment programs vary markedly in the sophistication and rigor of their methodology. Payers differ as to how such assessment information is integrated into their decision-making processes. Finally, coverage decisions about a specific technology can vary widely across the country.     

Media Coverage of Hazard Events: Analyzing the Assumptions*

Despite the widespread conviction that the mass media tend to “blow risks out of proportion,” the question has received little systematic attention. The mass-media literature also presents the opposite argument, namely that the media minimize the kinds of reporting that might upset large-scale capitalistic industries. Still other perspectives hold, on the one hand, that media reports tend to have more subtle anti-technology effects, created by “even-handed” coverage and on the other hand, that reporters give “establishment” figures the opportunity to “keynote” or “put the facts in perspective” in ways that exert a subtly pro-technology effect. Drawing on a systematic sample of 128 hazard events developed by researchers at another university and factually summarized by Lexis -Nexis , we analyze the effects of emotionalism on actual levels of coverage; a variety of analyses show that the only variables to exert significant effects are those that involve objective information, such as the number of casualties or the level of damage created. Given the argument that the effects of emotionalism can be conveyed in ways that are largely independent of the facts, e.g., by headlines, photographs, and “loaded” words, we next compare the emotionalism conveyed by factual summaries vs. the original stories and headlines. Even for incidents involving nuclear and/or toxic hazards, we find the net effect of the full stories is to lessen the emotionalism. Overall, the hypothesis receiving strongest support is that the “keynoting” helps create an overall impression that the “responsible authorities” are acting more responsibly than might be assumed on the basis of factual summaries alone. The widespread impression within the technical community, while understandable, may well have as much to do with the selective perceptions of scientists and engineers as with the actual pattern of media reporting.     

Dynamic pricing in the presence of consumer inertia

Customer behavior modeling has gained increasing attention in the context of dynamic pricing. As an important behavior phenomenon, consumer inertia refers to consumers' inherent tendency of purchase procrastination and may induce consumers to wait even when immediate purchase is optimal from an objective perspective. This paper studies a dynamic pricing problem for a monopolist firm selling perishable goods to consumers who may be influenced by inertia. We formulate this problem using the finite-horizon dynamic programming approach and derive the optimal dynamic pricing policy. We demonstrate that consumer inertia produces negative effects on firms' expected revenues and optimal prices, which are monotonically decreasing in both inertia depth and breadth. Through numerical illustrations, we further show that the marginal effects of inertia depth on optimal prices and expected revenues are decreasing, whereas the marginal effects of inertia breadth are increasing. Finally we propose some suggestions for firms to influence the level of consumer inertia.     

Network Evening News Coverage of Environmental Risk

ABC, CBS, and NBC's carefully crafted and expensively produced evening news broadcasts devoted 1.7% of their air time to 564 stories about man-made environmental risks during the period from January 1984 to February 1986. Little relationship was found between amount of coverage and public health risk. Instead, the networks appeared to be using traditional journalistic determinants of news (timeliness, proximity, prominence, consequence, and human interest) plus the broadcast criterion of visual impact to determine the degree of coverage of risk issues. Government, industry, and citizens accounted for two-thirds of the sources cited by the networks. Experts and spokespersons for environmental advocacy groups were sparsely used as sources. Given the media's need for news pegs, acute and chronic risk stories were covered differently. Acute risk stories were reported in a clearly defined cycle, peaking on the second day with on-the-scene reports and film-clips of devastation. In keeping with a decrease in visual drama, later reports were shorter and emphasized legal and political considerations. Chronic risk coverage followed the release of new scientific, legal, or political information.     

Robust portfolio planning in the presence of market anomalies

In this study, a short-term portfolio modeling formulation is developed using existing anomalies as a single determinant for daily Istanbul Stock Exchange National 100 Composite Index (ISE) and US dollars (USD) returns in a Robust optimization (RO) framework. Using anomalies in planning within an RO framework establishes a balance between risk seeking and risk averse behaviors, as generating profit from anomalies is risky and RO enables to settle down the extreme risk seeking behavior. Applications of the model using various data sets result in real profit generation such that terminal wealth figures increase considerably more than Wholesale Price Index (WPI). This study demonstrates that RO is a viable approach to make use of anomaly information for short-term profits.     

Multi-valued measures in DEA in the presence of undesirable outputs

Data envelopment analysis (DEA) evaluates the relative efficiency of a set of comparable decision making units (DMUs) with multiple performance measures (inputs and outputs). Classical DEA models rely on the assumption that each DMU can improve its performance by increasing its current output level and decreasing its current input levels. However, undesirable outputs (like wastes and pollutants) may often be produced together with desirable outputs in final products which have to be minimized. On the other hands, in some real-world situations, we may encounter some specific performance measures with more than one value which are measured by various standards. In this study, we referee such measures as multi-valued measures which only one of their values should be selected. For instance, unemployment rate is a multi-valued measure in economic applications since there are several definitions or standards to measure it. As a result, selecting a suitable value for a multi-valued measure is a challenging issue and is crucial for successful application of DEA. The aim of this study is to accommodate multi-valued measures in the presence of undesirable outputs. In doing so, we formulate two individual and summative selecting directional distance models and develop a pair of multiplier- and envelopment-based selecting approaches. Finally, we elaborate applicability of the proposed method using a real data on 183 NUTS 2 regions in 23 selected EU-28 countries.     

一类考虑反S型概率权重的供货中断库存模型

在连续盘点库存系统中应用零点订货库存(ZIO)策略,假设供应商工作和中断的持续时间分别服从独立的指数分布.首先,引入反S型权重函数刻画风险厌恶型决策者主观高估补货点供应商处于中断的小概率关键事件的行为偏好.其次,利用两个状态连续时间Markov链和更新报酬定理构建了长程平均成本模型,证明了成本函数的单峰性,对比讨论了结合数值算例与风险中性模型结论.最后,设计了近似条件得出最优订货量的解析表达式及成本的近似误差上界,配合基准集和随机数据集分别计算了160组和10 000组数值实验样本,验证了近似方法的有效性.     

一类考虑反 S型概率权重的供货中断库存模型

在连续盘点库存系统中应用零点订货库存（ZIO）策略,假设供应商工作和中断的持续时间分别服从独立的指数分布。首先,引入反S 型权重函数刻画风险厌恶型决策者主观高估补货点供应商处于中断的小概率关键事件的行为偏好。其次,利用两个状态连续时间Markov 链和更新报酬定理构建了长程平均成本模型,证明了成本函数的单峰性,对比讨论了结合数值算例与风险中性模型结论。最后,设计了近似条件得出最优订货量的解析表达式及成本的近似误差上界,配合基准集和随机数据集分别计算了160 组和 10 000 组数值实验样本,验证了近似方法的有效性。     

Coverage by directional sensors in randomly deployed wireless sensor networks

We study a novel “coverage by directional sensors” problem with tunable orientations on a set of discrete targets. We propose a Maximum Coverage with Minimum Sensors (MCMS) problem in which coverage in terms of the number of targets to be covered is maximized whereas the number of sensors to be activated is minimized. We present its exact Integer Linear Programming (ILP) formulation and an approximate (but computationally efficient) centralized greedy algorithm (CGA) solution. These centralized solutions are used as baselines for comparison. Then we provide a distributed greedy algorithm (DGA) solution. By incorporating a measure of the sensors residual energy into DGA, we further develop a Sensing Neighborhood Cooperative Sleeping (SNCS) protocol which performs adaptive scheduling on a larger time scale. Finally, we evaluate the properties of the proposed solutions and protocols in terms of providing coverage and maximizing network lifetime through extensive simulations. Moreover, for the case of circular coverage, we compare against the best known existing coverage algorithm.     

存在战略顾客的模仿创新研究

模仿者通过模仿创新对创新者产品(即原始产品)性能进行改进,推出模仿创新产品并与创新者进行竞争.战略顾客根据模仿创新产品的可获得性与性价比,跨期理性选择购买时机.文中研究了模仿者的性能改进能力与顾客对性能的偏好程度对模仿者能否超越创新者的影响.结论表明:当模仿创新产品的性价比低于原始产品时,如果模仿创新产品的推出能吸引大量新顾客,模仿者就能在市场份额与利润方面超越创新者;相反,当模仿创新产品的性价比高于原始产品时,模仿者能否在市场份额与利润方面超越创新者取决于其性能改进能力与顾客对性能的偏好程度间的匹配度.     

Bootstrap Inference in Partially Identified Models Defined by Moment Inequalities: Coverage of the Identified Set

This paper introduces a novel bootstrap procedure to perform inference in a wide class of partially identified econometric models. We consider econometric models defined by finitely many weak moment inequalities, ² We can also admit models defined by moment equalities by combining pairs of weak moment inequalities.
which encompass many applications of economic interest. The objective of our inferential procedure is to cover the identified set with a prespecified probability. ³ We deal with the objective of covering each element of the identified set with a prespecified probability in Bugni (2010a).
We compare our bootstrap procedure, a competing asymptotic approximation, and subsampling procedures in terms of the rate at which they achieve the desired coverage level, also known as the error in the coverage probability. Under certain conditions, we show that our bootstrap procedure and the asymptotic approximation have the same order of error in the coverage probability, which is smaller than that obtained by using subsampling. This implies that inference based on our bootstrap and asymptotic approximation should eventually be more precise than inference based on subsampling. A Monte Carlo study confirms this finding in a small sample simulation.     

考虑战略消费者行为风险的动态定价策略

本文研究的是存在战略消费者行为风险的动态定价问题,垄断厂商在需求不确定的有限时间内销售定量易逝商品,追求既定风险下的期望收益最大化;战略消费者在动态定价下基于参考价格安排购买时机.研究表明,厂商和消费者的行为策略间存在完美博弈均衡;在均衡价格范围内,战略购买行为改变了各交易主体的收益或支付,扩大了厂商收益不确定性风险;风险敏感的厂商定价趋于保守;交易信息透明是厂商实现预定目标的引导条件.     

Optimal procurement of long-term contracts in the presence of imperfect spot market

B2B spot market has grown rapidly and become an effective trading channel for commodity products. Besides long-term contract procurement from conventional suppliers (forward and option), a buyer can procure or sell commodities at any time in B2B spot market to adjust her inventory level. However, spot prices are generally volatile and the market is imperfect in the sense that spot trading may be realized with uncertainty in a given period of time and often comes with extra transaction cost. This paper considers a commodity buyer who can order forward and option contracts in advance and trade in a B2B spot market when spot price and demand are observed stochastically. Based on a single-period newsvendor model, we discuss three optimal order strategies and derive respective expected profits when the buyer is risk-neutral. The sensitivity of purchase costs, market liquidity and transaction cost is investigated. We also compare the optimal expected profits for different strategies to illustrate the effects of the two long-term contracts in the presence of the B2B spot market. We then extend our model to a multi-period setting and derive the optimal strategy. Finally, we numerically compute the optimal order strategy for a risk-averse buyer and analyze the impact of spot market, risk aversion, as well as the correlation between customer demand and spot price.     

Consumer Confidence in the Safety of Food and Newspaper Coverage of Food Safety Issues: A Longitudinal Perspective

This study develops a longitudinal perspective on consumer confidence in the safety of food to explore if, how, and why consumer confidence changes over time. In the first study, a theory-based monitoring instrument for consumer confidence in the safety of food was developed and validated. The monitoring instrument assesses consumer confidence together with its determinants. Model and measurement invariance were validated rigorously before developments in consumer confidence in the safety of food and its determinants were investigated over time. The results from the longitudinal analysis show that across four waves of annual data collection (2003–2006), the framework was stable and that the relative importance of the determinants of confidence was, generally, constant over time. Some changes were observed regarding the mean ratings on the latent constructs. The second study explored how newspaper coverage of food safety related issues affects consumer confidence in the safety of food through subjective consumer recall of food safety incidents. The results show that the newspaper coverage on food safety issues is positively associated with consumer recall of food safety incidents, both in terms of intensity and recency of media coverage.