价格持续期、信息传递与市场微观结构——基于非对称ACD模型的实证分析

本文建立两状态价格持续期的非对称对数自回归条件持续期模型,引入买卖价差、交易量、交易规模、指令流等信息交易间接度量变量,在刻画条件期望价格持续期对价格上升和下降两种状态的不对称依赖关系的同时,探讨价格持续期的信息传递机制并检验微观结构相关假说。实证分析表明,在选取样本中,滞后买卖价差与滞后交易量与条件期望价格持续期显著负相关;滞后买一(卖一)指令申报数量与条件期望价格持续期具有显著相关性,其符号由当期价格状态决定;大规模交易比中等规模交易对条件期望价格持续期有着更加显著的影响。即实证结果支持信息交易增加导致交易持续期减小的观点,不支持隐藏交易假说。     

The Dynamics of Domestic Gray Markets and Its Impact on Supply Chains

Gray markets are created by unauthorized retailers selling manufacturer's branded products. Similar to international gray markets, domestic gray markets are a growing phenomenon whose impact on supply chains is not clear. We consider a supply chain with one manufacturer and several authorized retailers who face a newsvendor problem and a domestic gray market. While a gray market provides an opportunity for retailers to clear their excess inventory (inventory‐correction effect), it also can be a threat to their demand (demand‐cannibalization effect). We first characterize the emerging equilibrium by assuming an MSRP environment. Comparing a decentralized and centralized system, we show that a wholesale pricing contract is quite efficient in a gray market environment; we explain the underlying mechanism and note some of the operational decisions that could hurt that efficiency. We show that the gray market price determines the degree of both the negative effects of demand‐cannibalization and the positive effects of inventory correction, which in turn determines the net impact of gray markets on the retailer's stocking choice and, ultimately, the manufacturer's profit. We then study the authorized retailers' problem as a price‐setting newsvendor. We observe that the gray market creates price competition between the authorized and unauthorized retailers, causing a drop in the primary market price. However, this price competition can be counteracted by the authorized retailers' stocking decision. Finally, we extend our model to consider the cases where the demand can be correlated across retailers.     

价格持续期的非对称对数ACD模型及其应用

通过建立两状态价格持续期的非对称对数ACD模型,刻画价格持续期过程对不同价格状态的不对称依赖关系和对未预期到的短价格持续期冲击与未预期到的长价格持续期冲击的不对称响应过程,并在该模型中引入买卖价差和交易规模变量,检验市场微观结构理论相关假说。模型拟合结果表明,价格上升和价格下降两种状态对价格持续期的影响不同,未预期到的短价格持续期冲击对价格持续期有正面影响,而未预期到的长价格持续期冲击对价格持续期有负面影响;对市场微观结构信息模型的实证分析表明,滞后买卖价差和滞后交易量具有信息含量,它们与价格持续期显著负相关;隐藏交易假说没有得到实证的支持,在选取样本中大规模交易量比中等规模交易量对价格持续期有更加显著的影响。     

On solutions that are better than most

A programmatic approach to solving decision problems by the use of ‘better than most’ (BTM) solutions is introduced. The BTM approach is contrasted to approaches that seek a solution whose outcome would be the best of all outcomes for feasible solutions, again according to criteria taken to represent the decision maker's objectives. This BTM approach is illustrated in terms of a decision problem in binary decision variables. This is followed by a discussion of (1) some of the probabilistic aspects of BTM solutions, including calculational experience, (2) a central BTM problem, akin to the problem of finding optimal methods in the more traditional approaches, (3) some ad hoc methods for overcoming this and other problems associated with the BTM approach, and (4) similarities and differences between the BTM approach and other approaches.     

Impact of secondary market on consumer return policies and supply chain coordination

In this paper, we develop a unified model to study the inventory management problem of a product and the coordination of the associated supply chain consisting of a single supplier and considerably many retailers in the presence of a secondary market. Specifically, consumer returns are allowed in the initial sales. Then, we introduce a secondary market to salvage the returns and the leftovers from the initial sales. In this secondary market, a discount price will be offered to the consumers but no returns are accepted. Moreover, between the primary and the secondary market, there is an internal market where retailers can trade among themselves so that they are able to adjust their inventory levels to prepare for the sales in the secondary market. We study the retailers' and the supply chain's inventory decision in this case and highlight the impact of the secondary market on the sales as well as on the supply chain coordination contracts. We conclude that the secondary market helps us to increase the total wholesale volume. Numerical examples show that the total sales profit is also increased. However, the secondary market aggravates the incentive conflict between the retailers and the supply chain on deciding the optimal inventory levels and hence requires the supplier to offer more generous buyback or sales rebate contracts for coordination of the supply chain. Finally, we extend our analysis to more general cases and also show that our results are robust to some of the modeling assumptions.     

信息共享下库存量牛鞭效应的影响因素研究

目前的研究多从供应链上游角度出发考虑传统牛鞭效应,而本文从供应链下游的角度研究库存量牛鞭效应得到了不一样的管理学启示.在需求函数方面,建立的需求模型包括市场规模、价格敏感性系数等更有现实意义的要素.在此,本文建立了包括一个零售商和一个制造商的简单两级供应链,得出了制造商在采用补充至订货点策略和最小均方差预测技术,在两种不同的信息共享模式下的库存量牛鞭效应表达式,并对他们的影响因素进行了分析.而且通过数值分析对模型进行了验证并得到新的结果.通过研究发现,信息共享能够显著降低制造商的库存量牛鞭效应;零售商和制造商的库存量牛鞭效应都不受市场规模的影响;零售商的库存量牛鞭效应在一定条件下不存在;相比于零售商提前期,制造商提前期对制造商的库存量牛鞭效应影响更大.同时,价格敏感性系数、价格自相关系数等因素对制造商库存量牛鞭效应也有不同程度的影响.     

消费者锚定效应下的动态定价与库存控制研究

在零售商-消费者两级供应链中, 零售商垄断销售市场, 研究基于消费者锚定效应的动态定价与库存问题。将消费者的锚定效应纳入决策模型中, 探讨消费者锚定的参考价格与产品的市场需求、价格的动态变化关系;利用动态规划理论建立了消费者锚定效应的动态定价与库存模型;在此基础上考虑利润折现和库存积压问题, 并分别构建了相应模型。数值分析表明, 消费者会根据市场价格的变化决定最佳的购买时机, 零售商的期望收益随着销售时间的延长而增加。     

Competing on Time: An Integrated Framework to Optimize Dynamic Time‐to‐Market and Production Decisions

This study develops a comprehensive framework to optimize new product introduction timing and subsequent production decisions faced by a component supplier. Prior to market entry, the supplier performs process design activities, which improve manufacturing yield and the chances of getting qualified for the customer's product. However, a long delay in market entry allows competitors to enter the market and pass the customer's qualification process before the supplier, reducing the supplier's share of the customer's business. After entering the market and if qualified, the supplier also needs to decide how much to produce for a finite planning horizon by considering several factors such as manufacturing yield and stochastic demand, both of which depend on the earlier time‐to‐market decision. To capture this dependency, we develop a sequential, nested, two‐stage decision framework to optimize the time‐to‐market and production decisions in relation to each other. We show that the supplier's optimal market entry and qualification timing decision need to be revised in real time based on the number of qualified competitors at the time of market‐entry decision. We establish the optimality of a threshold policy. Following this policy, at the beginning of each decision epoch, the supplier should optimally stop preparing for qualification and decide whether to enter the market if her order among qualified competitors exceeds a predetermined threshold. We also prove that the supplier's optimal production policy is a state‐dependent, base‐stock policy, which depends on the time‐to‐market and qualification decisions. The proposed framework also enables a firm to quantify how market conditions (such as price and competitor entry behavior) and operating conditions (such as the rate of learning and inventory/production‐related costs) affect time‐to‐market strategy and post‐entry production decisions.     

中国商品期货回报与现货价格变化测度研究——基于便利收益模型的视角

本文基于便利收益模型(CYM)的视角推导出商品期限结构、期货回报并对期货回报进行分解。选取我国三个商品期货交易所相关数据作为样本,对我国商品期货回报与现货价格变化进行测度研究。研究发现,在样本期内,商品期货回报和现货价格变化之间不存在密切关系;以展期收益或预期现货价格变化为条件的商品风险溢价具有时变性;平均展期收益反映了现货价格变化对风险溢价的预期偏离;期货期限结构、便利收益和展期收益准确地预测了现货价格变化。上述研究结果为我国商品期货回报与现货价格变化的测度和管理以及商品期货投资决策设计提供了一些有帮助的理论借鉴和操作性较强的方法选择。     

Decision Making and the Price Setting Newsvendor: Experimental Evidence

We present an experimental study of the price‐setting newsvendor problem, which extends the traditional framework by allowing the decision maker to determine both the selling price and the order quantity of a given item. We compare behavior under this model with two benchmark conditions where subjects have a single decision to make (price or quantity). We observe that subjects deviate from the theoretical benchmarks when they are tasked with a single decision. They also exhibit anchoring behavior, where their anchor is the expected demand when quantity is the decision variable and is the initial inventory level when price is the decision variable. When decision makers set quantity and price concurrently, we observe no significant difference between the normative (i.e., expected profit‐maximizing) prices and the decision makers’ price choices. Quantity decisions move further from the normative benchmarks (compared to when subjects have a single decision to make) when the ratio of cost to price is less than half. When this ratio is reversed, there is no significant difference between order levels in single‐ and multi‐task settings. In the multidecision framework, we also observe a tendency to match orders and expected demand levels, which subjects can control using prices.     

两种激励条件下三级供应链产品质量控制策略研究

本文基于四阶段Stackelberg博弈分析,研究了在三级供应链中如何进行产品质量控制策略问题。构建了由制造商、零售商与最终顾客组成的三级供应链博弈模型,制造商进行产品质量决策,即生产高质量产品或者低质量产品,零售商进行产品采购决策和零售定价决策,最终顾客根据两种产品质量水平和零售价格的差异,决定产品的购买数量;当零售商采购高质量产品时,制造商将会向其提供价格折扣策略;当零售商采购低质量产品时,制造商将会向其提供延迟付款策略。运用最优化原理,求解了制造商的产品质量水平、价格折扣、延迟付款期限和零售商的零售价格、最终顾客的购买数量,及期望收益函数。进行了算例分析,结果表明:高质量产品零售价格关于价格折扣下降幅度更大,而低质量产品零售价格关于延迟付款期限下降幅度更大;制造商提供的价格折扣越大、延迟付款期限越长,其期望收益将会减少,此时零售商的期望收益将会增加,最终顾客产品需求量将会增加;制造商的总期望收益函数将呈现"倒U"型,求解了期望收益的最大值及各契约参数的值,结果证明所提出的产品质量控制策略是可行的。     

Optimal price,warranty length and production rate for free replacement policy in the static demand market

In the present paper, a decision model is developed for producers in the static demand market to determine the optimal price, warranty length and production rate of a product to maximize profit based on the pre-determined life cycle. The free renewal warranty policy is considered under which failed products are renewed before the end of warranty length at no cost to consumers. The expected number of renewals based on warranty length is derived for Weibull life distributed products. The objective function includes both demand and cost functions, where production cost, warranty cost and inventory cost are involved. A solution approach using the maximum principle is described, and is applied to two specific cases of markets. The first case of market considers positive discount rate, and the second case of market considers zero discount rate. The economic sensitivity analysis is conducted to evaluate the effect of model parameters on the optimal solution. Some conclusions are drawn based on the sensitivity analysis.     

可加效用下基于消费者惰性的易逝品动态定价

本文在考虑销售商的风险规避态度和消费者惰性的情况下，研究了易逝品的动态定价策略。首先给出风险规避的销售商实施动态定价的马尔可夫决策过程，并运用MNL随机效用模型来刻画惰性消费者的购买决策，在此基础上，以风险规避销售商的期望效用最大化为目标，利用动态规划方法建立了可加效用下的易逝品动态定价模型，并探讨了消费者的惰性行为和销售商的风险规避态度对最优价格的影响。结论表明：在销售商的风险态度为风险规避的情况下，考虑消费者惰性行为的最优价格随库存水平的增加而降低，随剩余销售时间的增加而提高，消费者的惰性行为和销售商的风险规避态度对最优价格都存在负向影响，即最优价格随惰性深度的增加而降低，随惰性宽度的增加而降低，同时，销售商的风险规避态度越强烈，其制定的产品价格越低。     

An economic model of world energy 1900–2020

This report presents a model of the supply and demand for the world's energy during the period from 1900 to 2020. This model leads to the conclusion that even without new kinds of energy sources becoming practical, world energy demand can be met during the next 50 years with only a gradual increase in energy costs. Assumptions with respect to exhaustion of reserves that I regard as mildly conservative lead to a demand that can be satisfied by a 1.5 per cent per year energy price increase. This would raise the percentage of world GNP devoted to primary energy from the present 3–4 per cent in the year 2020. Eliminating per capita economic growth would reduce the required annual price increase only from 1.5 to 1.8 per cent. Eliminating normal technological progress in existing energy technologies would increase the required annual price increase from 1.5 to 2.7 per cent. The model shows oil and gas reaching their maximum share of the energy market during the 1980's. By 2020 approximately 50 per cent of all energy comes from nuclear power.The model provides a framework for the analysis of the world energy market under a wide variety of assumptions. In particular, the model allows explicitly for assumptions about technological progress, economies and diseconomies of scale, and the rate of substitution of cheaper energy sources for more expensive ones.     

考虑碳税对备件联合订购决策影响的研究

针对价格适中、消耗量高、对装备运行起重要作用的不可修备件的库存管理问题,构建了碳税政策下由多个基层站点和一个基地站点组成的两级保障链联合库存决策模型。模型以基层站点再申请点r_i、申请量Q_i和基地站点补给次数m_i为决策变量、以备件满足率为约束、以成本为目标。最后通过策略迭代方法对模型求解,并在数值分析中研究碳税对保障链决策的影响,结果表明：碳税政策虽然增加了保障链成本,但减少了碳排放,并且在合理的税费下能够实现显著的减排效果,有助于环境成本的降低。     

Inventory control of spares in a transport corporation — A case study

This paper reports on a study carried out in a transport organisation to find the optimal inventory of recoverable spares in a two-level inventory system consisting of a central depot and a set of 20 depots all over the territory of the organisation, with repair facilities. The problems of the present system are diagnosed and it is observed that the upper echelon's inability to meet the lower echelon's demand has resulted in an ever-increasing shortage. A mathematical model is developed to suit the system structure and a set of optimal inventory policies for recoverable spares at both the echelons is obtained for the case studied.     

Dynamic Pricing and Inventory Management with Regular and Expedited Supplies

We consider a periodic‐review inventory system with regular and expedited supply modes. The expedited supply is faster than the regular supply but incurs a higher cost. Demand for the product in each period is random and sensitive to its selling price. The firm determines its order quantity from each supply in each period as well as its selling price to maximize the expected total discounted profit over a finite or an infinite planning horizon. We show that, in each period if it is optimal to order from both supplies, the optimal inventory policy is determined by two state‐independent thresholds, one for each supply mode, and a list price is set for the product; if only the regular supply is used, the optimal policy is a state‐dependent base‐stock policy, that is, the optimal base‐stock level depends on the starting inventory level, and the optimal selling price is a markdown price that decreases with the starting inventory level. We further study the operational impact of such supply diversification and show that it increases the firm's expected profit, reduces the optimal safety‐stock levels, and lowers the optimal selling price. Thus that diversification is beneficial to both the firm and its customers. Building upon these results, we conduct a numerical study to assess and compare the respective benefit of dynamic pricing and supply diversification.     

Combined Pricing and Portfolio Option Procurement

In this paper, we study a single‐product periodic‐review inventory system that faces random and price‐dependent demand. The firm can purchase the product either from option contracts or from the spot market. Different option contracts are offered by a set of suppliers with a two‐part fee structure: a unit reservation cost and a unit exercising cost. The spot market price is random and its realization may affect the subsequent option contract prices. The firm decides the reservation quantity from each supplier and the product selling price at the beginning of each period and the number of options to exercise (inventory replenishment) at the end of the period to maximize the total expected profit over its planning horizon. We show that the optimal inventory replenishment policy is order‐up‐to type with a sequence of decreasing thresholds. We also investigate the optimal option‐reservation policy and the optimal pricing strategy. The optimal reservation quantities and selling price are shown to be both decreasing in the starting inventory level when demand function is additive. Building upon the analytical results, we conduct a numerical study to unveil additional managerial insights. Among other things, we quantify the values of the option contracts and dynamic pricing to the firm and show that they are more significant when the market demand becomes more volatile.     

Managing Product Rollovers

We study the product rollover strategy decision, where a firm decides whether to phase out an old generation of a product to be replaced by a new with either a dual or single roll. Our model considers a final build of the old product and preannouncement of the new, and incorporates dynamic pricing and inventory decisions. We find that the optimal price path closely follows changes in reservation price curves for the two products over time. We also identify the drivers of the rollover strategy decision, finding that lower market risk (faster diffusion, higher market responsiveness to preannouncements) and higher performance improvement for the new generation are associated with the single roll strategy.