Integrating dynamic pricing and inventory control for fresh‐agri product under consumer choice

In this article, we investigate a joint pricing and inventory problem for a retailer selling fresh‐agri products (FAPs) with two‐period shelf lifetime in a dynamic stochastic setting, where new and old FAPs are on sale simultaneously. At the beginning of each period, the retailer makes ordering decision for new FAP and sets regular and discount prices for new and old inventories, respectively. After demand realisation, the expired leftover is disposed and unexpired inventory is carried to the next period, for continuing selling. Unmet demand of all FAPs is backordered. The objective is to maximise the total expected discount profit over the whole planning horizon. We present a price dependent, stochastic dynamic programming model taking into account zero lead‐time, linear ordering costs, inventory holding and backlogging costs, as well as disposal cost. As the influence of the perishability, each customer selects his preferred choice based on the utility of product price and quality. By the way of constructing demand rate vector, the original formulation can be transferred to be jointly concave and tractable. Finally, we characterise the optimal policy and develop effective methods to solve the problem. We also conduct numerical studies to further characterise the optimal policy, and to evaluate the loss of efficiency under static policies when compared to the optimal dynamic policy.     

Joint decision on pricing and advertising for competing retailers under emergency purchasing

This paper investigates an inventory decision problem under the pricing and advertising dependent stochastic demand, and considers a joint decision on pricing and advertising for competing retailers who operate short-life-cycle products under emergency purchasing. The results indicate that the retailer always prefers to advertise whether under a single or dual channel system. However, both the optimal prices and stocks increase, whereas customer welfare decreases.     

Export taxes versus buffer stocks as optimal export policies under uncertainty

Optimal state-dependent export taxes and costly-to-store buffer stocks are compared in their welfare implications for an exporter possessing monopoly power in the international trade of a volatile commodity. Optimal stochastic control is used to derive the optimal buffer stock rules. It is shown that, if the internal and external fluctuations facing the exporter are large, if the storage costs are low, and if the price elasticity of export supply is small relative to that of export demand, the exporter would gain more from a buffer stock than from a optimal export tax. World welfare is always increased by buffer stocks, as opposed to tariffs; and, under some conditions, the foreign country might also benefit and, hence, not retaliate.     

Market Power and Buffer Stocks

The first-order conditions for a monopolist inventory holder are found under more general conditions than previously. It is found that monopolist storers facing inelastic demand will carry over more stock than they would with competition unless the elasticity of demand b increasing as price decreases or is constant. The competitive stocks equilibrium is identified and found to be Pareto optimal and hence Sams' result that there will be no losers from a rent-maximizing buffer stock policy is shown to be wrong.     

Inter-firm knowledge diffusion, market power, and welfare

We propose an infinite-horizon quantity-setting differential game with learning spillovers and organizational forgetting to analyze the optimal management decisions affecting the evolution of the stock of know-how, and, in turn, the dynamics of productive efficiency. Specifically, we study the long run impact of inter-firm knowledge diffusion on market power, i.e. the ability of a firm to raise the price above the marginal cost, and welfare. We consider two types of processes through which knowledge is acquired: (i) passive learning, or learning-by-doing, where managers do not actively invest in information and (ii) active learning, or learning-by-investing, where managers acquire new and additional information through specific investments in human capital. We show that: under (i), knowledge diffusion reduces market power; under (ii), knowledge diffusion reduces market power as long as learning spillovers are sufficiently important. From a welfare viewpoint, we also show that: under (i), knowledge diffusion is always welfare-enhancing; under (ii), weak spillovers are required in order for knowledge diffusion to be welfare-enhancing.     

A Stackelberg Game Model of Trade in Renewable Resources with Competitive Sellers*

We model international trade in renewable resources between a single buyer and competitive sellers as a Stackelberg differential game. The buyer uses unit and ad valorem tariffs to indirectly encourage conservation of the renewable resource under study. First, we show that the efficacy of these trade policy instruments in promoting conservation depends fundamentally on whether harvesting costs are stock dependent or independent. When harvesting costs are stock independent, the optimal open‐loop tariffs are dynamically consistent. In contrast, when harvesting costs are stock dependent, the optimal open‐loop tariffs are dynamically inconsistent. Secondly, we point out that whether the terminal value of the resource stock is higher with the stock independent or the stock dependent cost function cannot be resolved unambiguously. Thirdly, we show that it does not make sense for the buyer to use both tariffs simultaneously. Finally, we discuss the implications of these and other findings for renewable resource conservation in general.     

INVENTORIES AND FIXED INVESTMENT

We model fixed investment incorporating the inventory decision of the firm. Using Dutch listed nonfinancial firms during 1985–2000, we find that the inventory stock is negatively associated with fixed investment. The results suggest that the inventory stock may be used by the firm as a buffer in response to unexpectedly high demand. In addition, the firm may hold the inventory stock as a contingency substitute for the financial source of fixed investment.     

预付账款类供应链金融产品比较研究——基于系统动力学方法

文章基于系统动力学方法,在分析先票后货标准授信和保兑仓融资两种预付账款类供应链金融产品业务流程的基础上,构建两种供应链金融产品的系统动力学模型,探讨供应链金融实施的动态特性。在对模型的仿真研究中,通过考察供应链各节点企业的库存水平、库存波动情况、产品缺货量变化以及现金量变化情况,分析两种供应链金融产品的实施效果及其对供应链绩效的影响,并通过对比分析总结两者的差异。根据仿真得到的图形结果和相关统计数据,结果表明:两种融资方式都可以有效地解决分销商的资金短缺问题,但从对供应链绩效影响上看,供应链金融的实施还改善了供应链各节点企业的库存水平,两种预付款类供应链金融产品的差异主要体现在分销商库存维持成本及对核心企业库存水平的影响上,保兑仓融资更有利于降低分销商的库存成本,同时减少核心企业的库存水平。     

Adjustment Costs,Inventories and Output

This paper analyzes the optimal adjustment strategy of an inventory‐holding firm facing price‐ and quantity‐adjustment costs in an inflationary environment. The model nests both the original menu‐cost model that allows production to be costlessly adjusted, and the later model that includes price‐ and quantity‐adjustment costs, but rules out inventory holdings. It is shown that the firm's optimal adjustment strategy may involve stockouts. At low inflation rates, output is inversely related to the inflation rate, and the length of time demand is satisfied increases with the demand elasticity but decreases with the storage cost and the real interest rate.     

Preparing for catastrophic climate change

We study optimal adaptation to climate change when the harmful consequences of global warming are associated with uncertain occurrence of abrupt changes. The adaptation policy entails the accumulation of a particular sort of capital that will eliminate or reduce the catastrophic damage of an abrupt climate change when (and if) it occurs. The occurrence date is uncertain. The policy problem involves balancing the tradeoffs between the (certain) investment cost prior to occurrence and the benefit (in reduced damage) that will be realized after the (uncertain) occurrence date. For stationary economies the optimal adaptation capital converges monotonically to a steady state. In most cases, investment begins immediately. However, if the initial adaptation capital exceeds a pre-specified threshold level, which lies above the optimal steady state, investment is delayed while the capital stock decreases (due to depreciation) and commences only when it reaches this threshold level. For growing economies the optimal adaptation capital stock approaches the maximal economic level above which further accumulation is ineffective.     

Capacity expansion and dynamic monopoly pricing

We substitute to the plant size problem, as investigated by Chenery [Chenery, H., 1952. Overcapacity and the acceleration principle. Econometrica], a new version in which a profit-maximizing monopolist may combine its investment policy with a price policy adjusting demand upwards or downwards over time. We characterize the optimal price and investment policies. The optimal price policy determines an investment pattern either with constant increments of capacity over time, or becoming constant after a finite time. The existing capacity is either fully used at each instant between two investment dates; or the monopolist first quotes the instantaneous monopoly price and, thereafter, the price dampening instantaneous demand at the optimal installed capacity level.     

A complete characterization of optimal growth paths in an aggregated model with a non-concave production function

We use the Principle of Optimality in addition to the Euler equation in order to provide a characterization of optimal one-sector growth for all ranges of interest rates when the technology is not convex. Our key result is that the sequence of capital stocks is necessarily monotonic. For certain interest rates we show that the optimal path converges to a steady state only if the initial capital stock is above a critical level, otherwise it converges to zero. Finally, we demonstrate that the set of points for which the value function is differentiable is precisely the set of initial capital stocks from which there is a unique optimal path.     

Dynamic demand and noncompetitive pricing strategies

This paper studies optimal noncompetitive pricing strategies when the evolution of demand is the result of intertemporal considerations. Two different hypotheses of price expectations (myopia and perfect foresight) are treated. The major implication is that the slight modification from an instantaneous to a very fast consumer reaction may completely modify a monopolist's price strategy. More precisely, the price strategy should be volatile if the equilibrium demand is convex, independent whether the consumers act myopically or employ rational expectations. On the other hand, asynchronous dynamics (e.g., due to competitive fringe supply or different segments of demand) cannot explain even damped price oscillations. The equilibrium price strategy of the noncompetitive supplier exceeds the static rule if consumers employ myopic expectations; rational expectations may lead to prices above or below the static rule depending on the rate of discount.I am grateful for the helpful and elaborate comments from three anonymous referees.     

Combining an improved multi-delivery policy into a single-producer multi-retailer integrated inventory system with scrap in production

Operating in highly competitive global markets, management of the contemporary corporations constantly seeks to cut down various operating costs, such as inventory holding costs in the production units and their affiliated retailers. For the purpose of reducing stock holding cost, this paper combines an improved multi-delivery policy into a single-producer multi-retailer integrated inventory system with scrap in production. We extend a study by Chiu et al. (2013a) by augmenting an alternative n + 1 product distribution policy to their integrated inventory system. An initial delivery of finished items is shipped to multiple retailers to meet demand during the production unit's uptime. After the remaining production lot is produced and screened, fixed quantity n installments of the finished products are delivered to retailers at a fixed time interval. With the help of a mathematical model along with Hessian matrix equations, the closed-form optimal operating policies for the proposed system are derived. Further, the study demonstrates, through a numerical example, significant savings in stock holding cost for both the production unit and retailers.     

The Demand for Food Products: An Analysis of Interpurchase Times and Purchased Quantities

In this paper we study household purchase behaviour of storable food products. An inventory model is developed in which the household chooses an optimal stock level of the product. Storage of the product is costly, there is a fixed cost per purchase occasion, and the market price is sometimes discounted because of price promotions. We show that the optimal purchase policy is an s , S policy. The model is used to derive predictions on the correlations between interpurchase times and purchased quantities on the one hand, and prices on the other. These predictions are empirically verified using consumer panel data.     

随机需求曲线下的供应链零售商决策与牛鞭效应

本文讨论由一个供应商和一个零售商组成的简单两级供应链系统中,对于不同的随机需求函数,零售商的联合决策对牛鞭效应的影响。首先建立了基于具有随机扰动项的需求函数下的零售商优化联合决策(库存决策和定价决策)的一般模型;然后分析在随机需求函数为线性和等弹性(假设随机扰动项为独立同分布的正态分布)的情形下零售商决策对牛鞭效应的影响。对于随机线性需求函数,牛鞭效应不会发生;而对于随机等弹性需求函数,仿真实验结果显示,零售商优化联合决策能使牛鞭效应度量值随着曲线等弹性系数或刻度因子的增大而减小,但牛鞭效应始终会发生。因此,零售商在制定策略以减小牛鞭效应时,还应考虑不同需求曲线的形态和精细结构。     

On income fluctuations and capital gains

We consider the infinite time horizon problem of asymptotically maximizing the expected accumulated discounted utility in a one-good production economy. The available capital in a given period is given by the production of the previous period plus a random variable. The product of the discount and interest factors is either (1) greater than or (2) equal to one. Under (1) the optimal policy exists under certain conditions and always under (2). The optimal capital sequence almost surely goes to infinity. Under (1) with conditions on the utility one almost surely reaches a capital level above which the sequence is increasing.     

Fishing Technology and Optimal Distribution of Harvest Rates

This paper examines the problem of the optimal management of a joint-ownership fishing exploitation, where agents use different fishing gears. We consider a model in which the fishing activity may affect resource growth, not only through the harvest function but also through the natural growth rate of the resource. This allows us to capture the fact that some fishing gears alter the natural growth rate of the resource. We find that when the natural growth of the resource is altered by the fishing technology, the optimal stock is not independent of how harvest quotas are distribute among the agents. As a result, a fishing policy that firstly determines the optimum stock and, secondly, decides how to distribute the harvest among the different agents, will not be efficient. We also analyze the joint determination of optimal stock and harvest quotas and show that positive harvest quotas will only be optimal when countries are characterized by certain asymmetries.     

俄罗斯对华直接投资的贸易效应研究

俄罗斯一直是我国重要的贸易伙伴国,双边贸易潜力巨大,双向投资日趋活跃,中俄两国经贸关系不断深化。中俄双边投资规模和质量的快速提高,对中俄贸易的发展起到了积极的影响作用。通过分析俄罗斯对华直接投资对中俄贸易所产生的效应,能够更好地促进中俄经贸合作战略升级。本文从贸易与投资规模的角度,选取1992—2008年的中国对俄出口贸易额和对俄进口贸易额作为被解释变量,俄罗斯对华直接投资流量和存量作为解释变量,设立了多元回归分析模型,用以考察俄罗斯对华直接投资对中俄进出口贸易的短期和中长期影响。结果表明：俄罗斯对华直接投资流量对中国对俄出口贸易影响不显著,俄罗斯对华直接投资存量与中国对俄出口贸易之间存在互补效应,俄罗斯对华直接投资流量与中国对俄进口贸易之间存在互补效应,俄罗斯对华直接投资存量与中国对俄进口贸易之间存在替代效应。     

Stock adjustment for multicointegrated series

A typical stock adjustment model is a partial ajustment process to maintain simultaneously the two kinds of equilibrium relationships: a flow-flow relationship and a stock-flow relationship. We show that the stock adjustment model is an error correction model of ‘multicointegrated’ time series, and also an optimal decision rule generated from an intertemporal optimization problem. Economic examples in inventory model, housing construction, and consumption function are discussed.