石油勘探项目分阶段投资的最优时机选择

针对一次性投资决策理论与方法在石油勘探项目分阶段投资决策中应用的局限性,运用实物期权中的序列投资决策理论与方法,假设勘探储量转让价格服从跳跃扩散过程,构建了石油勘探项目分阶段投资的最优时机选择模型,逆序求解得出各阶段最优投资时机临界值的解析表达式,在此基础上通过案例演算对比分析了一次性投资和分阶段投资的最优时机决策规则.研究结果表明:一次性投资下的最优时机临界值高于分阶段投资下的最优时机临界值,且各阶段的最优投资时机临界值随勘探进程的不断深入呈现逐渐下降的趋势.     

基于成长期权的数字保存项目的投资时机选择研究

数字保存是数字图书馆建设环节的关键技术,由于开发技术、市场环境等不确定的存在,投资决策的时机选择决定了投资的收益.借助实物期权理论,通过合理假设,构建了基于成长期权理论的数字保存项目的投资时机决策模型,并求解出了项目的最佳投资时机.     

IPO市场条件下风险投资退出时机的抉择

本文利用博弈论和信息经济学的理论知识。通过建立一个两阶段基本模型，给出了风险企业的退出条件。由于风险投资家要重复地参与资本市场。又将两阶段模型推广到无限期重复博弈，通过建立声誉机制可解决不同类型风险企业的退出时机问题。对低质量的企业继续增加投资的目的不是为了建立声誉，而是为了增加收益。对年轻的风险投资家而言，要建立自己的声誉可通过使企业价格偏低来实现。     

省珠脑速算师资培训班结束

为了巩固我省珠脑逮算教育取得的成绩，继续提高珠脑逮算技术水平，使这项工作能够再登一个新台阶，省珠协利用寒假的有利时机，对全省各地市珠协珠脑逮算培训点的教练进行了培训．     

存在强势零售商的竞争渠道内生时机

在存在强势零售商的非对称竞争渠道中,首先在三种博弈时机下分析协商机制、市场竞争以及强势零售商讨价还价能力对均衡结果的影响,然后探讨竞争渠道的内生时机,最后分别从销售成本和卖场流量两个角度对基本模型进行拓展。研究表明:协商机制提高强势零售渠道的市场需求和利润;当市场竞争较为激烈时,制造商将从零售商竞争中获得"渔翁之利",强势零售商过于挤压产品批发价格将遭受利润损失;以往研究中关于零售商同步领导的博弈时机假设是有缺陷的,序贯领导才是竞争渠道的内生时机,并且销售成本差异和卖场流量差异将缩小内生时机的双均衡区域。     

基于可用度的复杂结构装备检修时机决策模型

为最大限度地提高装备的可用度水平,检修工作十分必要,而检修时机的确定即成为一个重要的决策问题。对于复杂结构装备,组成部件的数量、寿命分布及对应的维修策略等都是可用度的影响因素。在采取预防性维修和修复性维修相结合策略的基础上,推导出了单装备任务周期内可用度关于检修时机的表达式,以此获得了装备群系统的检修时机决策模型,并充分考虑了部件工作年龄的影响。通过实例分析,验证了模型的合理性和实用性。     

基于可用度的复杂结构装备检修时机决策模型

为最大限度地提高装备的可用度水平,检修工作十分必要,而检修时机的确定即成为一个重要的决策问题。对于复杂结构装备,组成部件的数量、寿命分布及对应的维修策略等都是可用度的影响因素。在采取预防性维修和修复性维修相结合策略的基础上,推导出了单装备任务周期内可用度关于检修时机的表达式,以此获得了装备群系统的检修时机决策模型,并充分考虑了部件工作年龄的影响。通过实例分析,验证了模型的合理性和实用性。     

委托代理冲突下的企业投融资决策

采用实物期权与均衡定价理论,研究委托-代理冲突下的企业投融资决策问题.考虑管理者拥有企业投融资决策权时,其如何同时选择投资时机、投资规模及资本结构.分析了管理者持股与项目风险(不确定性)对企业非效率投融资的影响.数值分析表明:给定资本结构下,杠杆企业管理者决策的投资时机与投资规模变化呈现出负相关;对比于纯股权融资企业,杠杆企业管理者加速了投资期权的执行并增大了投资规模;财务杠杆率是管理者持股比例的U形函数,且管理者持股比例的增大,会加速投资期权的执行、增大投资规模与债务融资规模,并降低代理成本;项目风险的增大会导致企业投资时机、投资规模、债务融资规模和代理成本增大及财务杠杆率降低.     

基于泊松跳跃的最佳并购时机比较研究

基于最优停时理论、实物期权方法、平滑粘贴条件和道格拉斯生产函数转换,通过时机模型构建与求解,比较分析了无泊松跳跃和有泊松跳跃两种情形下的最佳并购时机。研究结果显示,驱动企业并购的主要是协同效应;企业并购存在仅与并购双方相对股价有关的最佳并购时机及其对应的并购区域;泊松跳跃使并购阈值下界和并购阈值上界右移,并购区域变宽,选择最佳并购时机需要更多信息;在相对股价进入并购区域时,即可实施并购,否则,主并方的最佳策略为持有等待期权,即继续等待。研究结论可为企业选择最佳并购时机,尤其是国有企业选择产权转让的最佳时机提供直接理论指导和实践借鉴。     

一道习题的研究性学习

目前，高中数学课程改革中“探究型的学习方式”、“研究性学习”理念已深入人心．笔者也在不断创造“研究性学习”的时机和氛围，笔者发现在习题教学中进行研究性学习，会收到良好的效果，本文介绍一个案例．     

考虑海外代购的品牌商定价模型研究

随着海外代购体量的日趋增大,代购带来的低价威胁对于在不同国家不同市场销售产品的公司来说已经成为一个日益严重的问题。同时,代购渠道中假货的问题也愈发严重。因此,在海外代购背景下探究产品定价模型具有必要性。以往研究普遍认为这种未经授权的销售会削减品牌方的利润,但实则不然。基于这一发现,本研究为在两个不同市场销售相同产品但面临代购低价威胁的公司制定考虑代购的市场定价模型。由公司制定两个市场的价格,消费者选择是否从包括代购在内的三个渠道购买产品。推出两个授权市场的最优价格,分析各参数变化对最优价格的影响,并校验最优价格对消费者需求和总利润的影响。模型分析表明,高价市场中有部分消费者需求转向海外代购,同时低价市场的消费者需求也受到了影响,且在一定条件下,提高高价市场的产品定价能够扩大低价市场的需求,从代购的角度解释了现实中需求曲线向上倾斜的现象。此外,两个独立市场之间的价格差距对代购市场的销售也产生了积极影响,并且在某些条件下,增大价格差距可以提高公司的收益水平。随后讨论了一种极端模型和三种扩展模型,通过模型分析表示,扩展后的定价模型也显示出与基础市场模型相似的灵敏度分析结果,同样得到两个市场的价差扩大会导致代购市场的销售额增加的结论,并且在一定条件下,公司的利润更高,增加了结论的可信度。     

Improving the efficiency of the purchasing process using total cost of ownership information: The case of heating electrodes at Cockerill Sambre S.A.

Improving the efficiency of the purchasing process provides important opportunities to increase a firm's profitability. In this paper we introduce a mathematical programming model that uses total cost of ownership information to simultaneously select suppliers and determine order quantities over a multi-period time horizon. The total cost of ownership quantifies all costs associated with the purchasing process and is based on the activities and cost drivers determined by an activity based costing system. Our approach is motivated by the purchasing problem of heating electrodes at Cockerill Sambre, a Belgian multinational steel producer. In this case quality issues account for more than 70% of the total cost of ownership making the quality of a supplier a critical success factor in the supplier selection process.     

An economic order quantity model for deteriorating item in a purchasing system with multiple prepayments

In the classic economic order quantity model the purchasing cost of an order should be paid at the time of its receipt. Sometimes, retailers ask purchasers to pay all or a fraction of the purchasing cost in advance and sometimes allow them to divide the prepayment into several equal-sized parts. In this paper, economic order quantity model for a deteriorating product with and without shortage under consecutive prepayments are developed. Numerical examples illustrate the proposed models and solution method and sensitivity analysis provides some managerial insights for managers.     

A multi-product continuous review inventory system in stochastic environment with budget constraint

Common characteristics of inventory systems include uncertain demand and restrictions such as budgetary and storage space constraints. Several authors have examined budget constrained multi-item stochastic inventory systems controlled by continuous review policies without considering marginal review shortage costs. Existing models assume that purchasing costs are paid at the time an order is placed, which is not always the case since in some systems purchasing costs are paid when order arrive. In the latter case the maximum investment in inventory is random since the inventory level when an order arrives is a random variable. Hence payment of purchasing costs on delivery yields a stochastic budget constraint for inventory. In this paper with mixture of back orders and lost sales, we assume that mean and variance of lead time demand are known but their probability distributions are unknown. After that, we apply the minimax distribution free procedure to find the minimum expected value of the random objective function with budget constraint. The random budget constraint is transformed to crisp budget constraint by chance-constraint technique. Finally, the model is illustrated by a numerical example.     

A multi-product continuous review inventory system with stochastic demand,backorders, and a budget constraint

Common characteristics of inventory systems include uncertain demand and restrictions such as budgetary or storage space constraints. Several authors have examined budget constrained multi-item stochastic inventory systems controlled by continuous review policies without considering marginal shortage costs. Existing models assume that purchasing costs are paid at the time an order is placed, which is not always the case since in some systems purchasing costs are paid when orders arrive. In the latter case the maximum investment in inventory is random since the inventory level when an order arrives is a random variable. Hence payment of purchasing costs on delivery yields a stochastic budget constraint for inventory. This paper models a multi-item stochastic inventory system with backordered shortages when estimation of marginal backorder cost is available, and payment is due upon order arrival. The budget constraint can easily be converted into a storage constraint.     

A Day-to-Day Buying Policy for Commodities — A Study of Purchasing Maize

The majority of the imported raw materials used by European industry have to be purchased in commodity markets where prices fluctuate over time. The overall purchasing decision contains several component stages. The work described in this paper concentrates on the final stage of this process, the tactical buying policy. A major difficulty lies in the definition of a proper measure of performance, so as to assess the merits of any proposed buying policy. The measures previously suggested by Kingsman and Taylor are discussed, and a new measure, thought to be more appropriate, is put forward. The paper describes a new heuristic buying policy, which is applied to the purchasing of maize. The policy uses Taylor's price-trend forecasting model and leads to purchasing costs which are shown to be significantly lower than the average market prices and better than those obtained from Kingsman's pricebreak policy.     

Using copulas to model repeat purchase behaviour – An exploratory analysis via a case study

We develop a model of the evolution of inter-purchase times for a consumer-packaged product. After the introduction of the product, a consumer waits to make the initial purchase, then either waits to repurchase or decides not to. A repurchasing consumer repeats this decision process. The components of the model are the repurchase probability and the density function of the time to repurchase at each stage of the purchasing cycle. Issues of interest are: the strength of the dependency between successive repurchase times; the number of repeat purchases before stability occurs; the effects of consumer characteristics on inter-purchase times. The model of individual purchasing behaviour can be transformed via simulation to produce sales time series for a given population. As an example, the model is estimated for a product using Australian panel data. The accuracy of the model’s prediction is compared with an existing model.     

Incorporating quantity discounts and their inventory impacts into the centralized purchasing decision

Multi-site organizations must balance conflicting forces to determine the appropriate degree of purchasing centralization for their respective supplies. The ability to garner quantity discounts represents one of the primary reasons that organizations centralize procurement. This paper provides methodologies to calculate optimal order quantities and compute total purchasing and inventory costs when products have quantity discount pricing. Procedures for both all-units and incremental quantity discount schedules are provided for four different strategic purchasing configurations (scenarios): complete decentralization, centralized pricing with decentralized purchasing, centralized purchasing with local distribution, and centralized purchasing and warehousing. For ordering decisions under local distribution, procedures to determine optimal order quantities and costs are presented in a precise form that could be easily implemented into spreadsheets by practicing managers. For the more complicated multi-echelon scenarios, we introduce a single-cycle policy with a tailored aggregation refinement step that performs very well under experimentation when compared to a conservative bound.     

Optimizing a Production System with a Fixed Delivery Schedule

This note considers a model in which a manufacturing company purchases a raw material, manufactures a product (at a finite rate) and ships a fixed quantity of the product to a single customer at fixed and regular intervals of time, as specified by the customer. In general there are several shipments made during each production run. The objective is to determine a purchasing and production schedule which minimises the total cost of purchasing, manufacturing and stockholding. It extends previously published work by considering the possibility that a single raw material purchase provides stock for several production runs or that several raw material purchases provide stock for a single production run.     

Fighting strategies in a market with counterfeits

Counterfeiting is a widely spread phenomenon and has seen rapid growth in recent years. In this paper, we adopt the standard vertical differentiation model and allow consumers the choices of purchasing an authentic product, purchasing a counterfeit, or not buying. We focus on how non-deceptive counterfeits, which consumers know at time of purchase that the products are counterfeits with certainty, affect the price, market share and profitability of brand name products. We also consider the strategies for brand name companies to fight counterfeiting. We compare different fighting strategies in a market with one brand name product and its counterfeit, and derive equilibrium fighting strategies in a market with two competing brand name products and a counterfeit under general conditions.