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981.
982.
The methods presented in this article are based on the qualitative and quantitative analysis of close-out data drawn from a portfolio of 38 modification projects. The primary premise is that modification projects are intrinsically subject to quantity and complexity growth during the course of detailed engineering as a consequence of the indeterminate interface with the existing facility. The normative project control routines need to be supplemented by material take-offs-based weight monitoring as a basis for re-estimation and re-calibration of the project baselines as detailed engineering proceeds in order to mitigate this uncertainty as early as possible. Similarly, estimating needs to be based on norms drawn from performance measurement of modification work rather than extrapolations from greenfield projects, particularly the work performed on the platforms. This article presents a portfolio of project control methods based on the performance measurement principle covering the short term of single projects as well as the longer term multi-project perspective. 相似文献
983.
Peter Burgherr 《Risk analysis》2013,33(1):146-160
We analyze the risk of severe fatal accidents causing five or more fatalities and for nine different activities covering the entire oil chain. Included are exploration and extraction, transport by different modes, refining and final end use in power plants, heating or gas stations. The risks are quantified separately for OECD and non‐OECD countries and trends are calculated. Risk is analyzed by employing a Bayesian hierarchical model yielding analytical functions for both frequency (Poisson) and severity distributions (Generalized Pareto) as well as frequency trends. This approach addresses a key problem in risk estimation—namely the scarcity of data resulting in high uncertainties in particular for the risk of extreme events, where the risk is extrapolated beyond the historically most severe accidents. Bayesian data analysis allows the pooling of information from different data sets covering, for example, the different stages of the energy chains or different modes of transportation. In addition, it also inherently delivers a measure of uncertainty. This approach provides a framework, which comprehensively covers risk throughout the oil chain, allowing the allocation of risk in sustainability assessments. It also permits the progressive addition of new data to refine the risk estimates. Frequency, severity, and trends show substantial differences between the activities, emphasizing the need for detailed risk analysis. 相似文献
984.
This paper deals with the problem of determining an optimal length of credit period from the perspective of supplier. We assume that a retailer jointly determines the unit retail price and order size to maximize profit when he/she purchases a product for which the supplier offers a trade credit. Two widely used demand functions are adopted for the study in which demands are decreasing functions of the retail price. A procedure is presented which shows how to achieve an optimal length of credit period for suppliers. The effects of credit period on the behaviour of retailers are also investigated using an example. 相似文献
985.
Mehmet Gümü Shanling Li Wonseok Oh Saibal Ray 《Production and Operations Management》2013,22(4):758-776
In this article, we study the price partitioning decisions of online retailers regarding shipping and handling (S&H) fees. Specifically, we analyze two partitioning formats used by retailers in this context. In the first scenario, retailers present customers with a price that is partitioned into a product price and a separate S&H surcharge (the PS strategy); in the second, customers are offered free shipping through a non‐partitioned format where the product price already includes the shipping cost (the ZS strategy). We first develop a stylized game‐theoretic model that captures the competitive dynamics between (and within) these two formats. Analysis of the model provides insights into how both firm and product level characteristics drive a retailer's strategic choice regarding which partitioning format to adopt and, hence, determines the equilibrium market structure in terms of proportion of ZS and PS retailers. Subsequently, we conduct empirical analyses, based on product and S&H prices data for two different product categories (digital cameras and printers) collected from online retailers, to validate all the results of our theoretical model. We establish that PS retailers charge lower product prices than ZS ones, but the total price (product + S&H) charged is higher for the first group. The S&H charge for PS retailers can be significant—it is, on average, 5.4% (printers) and 3.0% (digital cameras) for our two product categories. Furthermore, retailers which are popular and/or face risky cost environment are more likely to opt for the ZS strategy, while retailers whose portfolio mostly includes large or heavy products with high cost (S&H)‐to‐price ratios usually choose the PS strategy. Lastly, our empirical study also illustrates that the price adjustment behavior of retailers is affected by their shipping‐fee policies—for example, ZS retailers change their product prices almost 1.5 times more frequently than PS ones. 相似文献
986.
Despite the spread of cost‐driven outsourcing practices, academic research cautions that suppliers' cost advantage may weaken manufacturers' bargaining positions in negotiating outsourcing agreements, thereby hurting their profitability. In this study, we attempt to further understand the strategic impact of low‐cost outsourcing on manufacturers' profitability by investigating the contractual form of outsourcing agreements and the industry structure of the upstream supply market. We consider a two‐tier supply chain system, consisting of two competing manufacturers, who have the option to produce in‐house or to outsource to an upstream supplier with lower cost. To reach an outsourcing agreement, each manufacturer engages in bilateral negotiation with her supplier, who may be an exclusive supplier or a common supplier serving both manufacturers. Our analysis shows that wholesale‐price contracts always mitigate the competition between manufacturers regardless of whether they compete with price or quantity. In contrast, two‐part tariffs intensify the competition when the manufacturers compete with quantity, but soften it when they compete with price. As a result, when outsourcing with two‐part tariffs, the manufacturers may earn lower profits than they would from in‐house production, although the suppliers are more cost efficient. This suggests that managers have to be wary about the downside of using coordinating contracts such as two‐part tariffs when pursuing low‐cost outsourcing strategies. Our analysis also sheds some light on the profitability of using an exclusive supplier for outsourcing. When outsourcing with wholesale‐price contracts, the competing manufacturers are better off outsourcing to an exclusive supplier. However, when outsourcing with two‐part tariffs, the manufacturers may earn higher profits by outsourcing to a common supplier than to an exclusive one when the manufacturers' bargaining power is sufficiently strong (weak) under quantity (price) competition. 相似文献
987.
股价暴涨直观上带来高收益,激发市场正面情绪,那么为什么暴涨被视为风险?本文利用2006年至2016年中国A股上市公司数据,通过计量建模对暴涨股票的特征和日后的市场表现进行刻画。实证发现:(1)股价暴涨频度高的股票,呈现低资产收益率、高市值账面比、多散户持股、少沪深300成份股等特点;(2)易发生暴涨的股票其长期超额收益率更低,未来有更大的暴跌风险和更高的收益率波动率;(3)对于运营基本面较差、市场过于乐观、信息披露质量较低的股票,暴涨后的暴跌风险更加明显。研究结论在不同代理变量选择、多种计量模型设定下均稳健成立。本文揭示了暴涨不仅仅是极端价格波动,而且更容易发生在高风险股票中,未来蕴含着更大的潜在损失。暴涨是实实在在的风险。 相似文献
988.
Most existing risk management models for process industries do not consider the effect of insurance coverage, which results in an overestimation of overall risk. A model is presented in this article to study the effect of insurance coverage of health, safety, environmental, and business risks. The effect of insurance recovery is modeled through the application of adjustment factors by considering the stochastic factors affecting insurance recovery. The insurance contract's conditions, deductibles, and policy limits are considered in developing the insurance recovery adjustment factors. Copula functions and Monte Carlo simulations are used to develop the distribution of the aggregate loss by considering the dependence among loss classes. A case study is used to demonstrate both the practical application of the proposed insurance model to improve management decisions, and the mitigating effect of insurance to minimize the residual risk. 相似文献
989.
拍卖中的串通出价 总被引:3,自引:0,他引:3
本文在扩展的独立私有价值模型下,考虑第二价格和第一价格拍卖机制下的串通出价行为和卖方对串通出价的反映。第二价格串通出价机制和第一价格串通出价机制分别为在这两种拍卖机制下的激励相容、有效的直接显示串通出价机制。我们发现卖方若知道有串通行为,可以提高保留价来减少损失。由于卖方一般情况下不太可能确定是否存在串通行为及参与串通的人数k,但可以确定给定保留价时串通人数的'最优反应',在第二价格串通出价机制下,给定串通人数,增加保留价可以提高卖方的期望收益,对于确定的保留价,串通人数的增加会减少卖方的期望收益。从而存在这样的纳什均衡:所有的投标人串通,即,k=N,而卖方宣布与之相应的保留价r (N)。当然,并不是所有的串通出价对投标人都是有利可图的,在第一价格拍卖机制下,若卖方可以调整保留价,只有当参与竞投的人很多时,串通出价才有利可图。 相似文献
990.
涨跌幅限制与股票价格行为分析 总被引:4,自引:1,他引:4
对于股票在达到涨跌幅限制后价格如何变化的解释有两种假设:信息假设和过度反应
假设. 通过对1997 年到2000 年上海证券交易所股票在达到涨跌幅限制后隔夜期间与交易期
间的非正常收益进行检验,以揭示达到涨跌幅限制后股票的价格行为. 结果表明在达到涨跌幅
限制后的隔夜期间股票价格存在价格持续现象,而在交易期间存在价格反转现象. 这个结果一
方面说明了沪市存在着过度反应,另一方面也说明了上海证券交易所10 %的涨跌幅限制在限
制噪声交易者的过度反应有一定的作用. 相似文献