Indifference mapping for multiple criteria decisions

Indifference mapping uses multi dimensional scaling techniques to allocate multi criteria policies to points in a space based on an input which consists of those pairs of policies which are equally attractive. The paper takes sets of policies for each of which a single value has been pre-assigned and maps them in two dimensions by applying a probability law to the assessment of indifferent pairs. The paper shows that the maps can be used both to deduce the original value of each policy and can also deduce the probability law which was applied.     

Stochastic Algorithms,Symmetric Markov Perfect Equilibrium,and the ‘curse’ of Dimensionality

This paper introduces a stochastic algorithm for computing symmetric Markov perfect equilibria. The algorithm computes equilibrium policy and value functions, and generates a transition kernel for the (stochastic) evolution of the state of the system. It has two features that together imply that it need not be subject to the curse of dimensionality. First, the integral that determines continuation values is never calculated; rather it is approximated by a simple average of returns from past outcomes of the algorithm, an approximation whose computational burden is not tied to the dimension of the state space. Second, iterations of the algorithm update value and policy functions at a single (rather than at all possible) points in the state space. Random draws from a distribution set by the updated policies determine the location of the next iteration's updates. This selection only repeatedly hits the recurrent class of points, a subset whose cardinality is not directly tied to that of the state space. Numerical results for industrial organization problems show that our algorithm can increase speed and decrease memory requirements by several orders of magnitude.     

Exploring the Dimensionality of Trust in Risk Regulation

This article investigates possible differential levels of trust in government regulation across five different risk contexts and the relationship between a number of concepts that might be thought of as comprising distinctive "dimensions" of trust. It appeared that how people perceive government and its policies toward risk regulation was surprisingly similar for each of the five risk cases. A principal-component analysis showed that the various trust items could best be described by two dimensions: a general trust dimension, which was concerned with a wide range of trust-relevant aspects, such as competence, care, fairness, and openness, and a scepticism component that reflects a sceptical view regarding how risk policies are brought about and enacted. Again, the results were surprisingly similar across the five risk cases, as the same solution was found in each of the different samples. It was also examined whether value similarity has an additional value in predicting trust in risk regulation, compared to the more conventional aspects of trust. Based on the two independent trust factors that were found in this study, a typology of trust is proposed that ranges from full trust to a deep type of distrust. It is argued that for a functioning society it could well be more suitable to have critical but involved citizens in many situations.     

基于低碳视角的政府监管与制造商生产的演化博弈研究

政府制定的监管政策对制造商生产策略的选择具有重要影响。本文基于低碳视角,引入政府碳税系数、补贴系数、低碳产品生产成本等参数,针对税收与补贴混合政策、单一税收政策和单一补贴政策三种模式,分别建立了政府与制造商之间决策行为的演化博弈模型,对比分析了不同监管政策下政府和制造商达到均衡所需条件的差异,并进一步探讨了影响政府、制造商决策的关键因素。研究结果表明,当初始生产低碳产品的制造商比例相同时,政府实施混合政策比单一税收政策或补贴政策对制造商生产低碳产品的激励作用更加明显。政府监管与政府低碳税收、高碳产品罚款和监管成本有关,制造商生产低碳产品受到产品成本、收益的影响。研究结论不仅为政府制定低碳产品政策提供了科学依据,也为制造商选择低碳产品策略给予了决策支撑。     

A Migration Study of Mother's Work,Welfare Participation,and Child Development

Abstract. This paper investigates how women's migration and labor supply behaviors respond to changes in welfare policies and labor market conditions, controlling for endogenous initial residence and unobserved heterogeneity. It also traces out how these responses influence educational inputs and child outcomes. The simulation results show that poor and low‐educated single women with children do change their residential locations in response to changes in welfare policies and labor market conditions. The magnitude of this response in the form of migration is rather modest. More importantly, however, such policy changes often have large and important impacts on particular at‐risk groups.     

THE VALUE OF SKU RATIONALIZATION IN PRACTICE (THE POOLING EFFECT UNDER SUBOPTIMAL INVENTORY POLICIES AND NONNORMAL DEMAND)

Several approaches to the widely recognized challenge of managing product variety rely on the pooling effect. Pooling can be accomplished through the reduction of the number of products or stock‐keeping units (SKUs), through postponement of differentiation, or in other ways. These approaches are well known and becoming widely applied in practice. However, theoretical analyses of the pooling effect assume an optimal inventory policy before pooling and after pooling, and, in most cases, that demand is normally distributed. In this article, we address the effect of nonoptimal inventory policies and the effect of nonnormally distributed demand on the value of pooling. First, we show that there is always a range of current inventory levels within which pooling is better and beyond which optimizing inventory policy is better. We also find that the value of pooling may be negative when the inventory policy in use is suboptimal. Second, we use extensive Monte Carlo simulation to examine the value of pooling for nonnormal demand distributions. We find that the value of pooling varies relatively little across the distributions we used, but that it varies considerably with the concentration of uncertainty. We also find that the ranges within which pooling is preferred over optimizing inventory policy generally are quite wide but vary considerably across distributions. Together, this indicates that the value of pooling under an optimal inventory policy is robust across distributions, but that its sensitivity to suboptimal policies is not. Third, we use a set of real (and highly erratic) demand data to analyze the benefits of pooling under optimal and suboptimal policies and nonnormal demand with a high number of SKUs. With our specific but highly nonnormal demand data, we find that pooling is beneficial and robust to suboptimal policies. Altogether, this study provides deeper theoretical, numerical, and empirical understanding of the value of pooling.     

TIME‐BASED PRICING AND LEADTIME POLICIES FOR A BUILD‐TO‐ORDER MANUFACTURER

We studied time‐based policies on pricing and leadtime for a build‐to‐order and direct sales manufacturer. It is assumed that the utility of the product varies among potential customers and decreases over time, and that a potential customer will place an order if his or her utility is higher than the manufacturer's posted price. Once an order is placed, it will be delivered to the customer after a length of time called “leadtime.” Because of the decrease in a customer's utility during leadtime, a customer will cancel the order if the utility falls below the ordering price before the order is received. The manufacturer may choose to offer discounted prices to customers who would otherwise cancel their orders. We discuss two price policies: common discounted price and customized discounted price. In the common discounted price policy, the manufacturer offers a single lower price to the customers; in the customized discounted price policy, the manufacturer offers the customers separately for individual new prices. Our analytical and numerical studies show that the discounted price policies results in higher revenue and that the customized discounted price policy significantly outperforms the common discounted price policy when product utility decreases rapidly. We also study two leadtime policies when production cost decreases over time. The first uses a fixed leadtime, and the second allows the leadtime to vary dynamically over time. We find that the dynamic leadtime policy significantly outperforms the fixed leadtime policy when the product cost decreases rapidly.     

Managing consumer returns in high clockspeed industries

In this study, we address control policies to manage the collection of products that have been returned by consumers to retailers after they have been sold. Specifically, we model a consumer returns process where the operational decision of interest is the frequency in which returns are picked up from a collection point and then processed at a centralized location. Returns decay in value over time according to their industry clockspeed. Hence there is an intrinsic tradeoff in the decision – a longer interval between collections not only reduces transportation cost, but also reduces the value of asset recovery.We analyze a stylized model with a single collection point and a centralized returns processing center. Given an asset decay rate and a fixed transportation cost we determine the optimal collection interval. We later expand the analysis to the case of a capacitated returns processing center. We also explore the value of information (number of returns held at the collection point) sharing between a collection point and the central processing facility. We find that the voi is quite sensitive to parametric settings ranging upwards to over 20% with a median value of 5.0%. We find that the voi increases with respect to the asset value decay rate and the rate of returns, while it decreases with respect to the shipping cost.     

Public planning and political strategy

Planning theory and practice derived from corporate experience, management science and rational decision theory have had little influence on decision-making in the public sector. The political environment and organizational complexity of public decision making render conventional approaches to objective, rational, comprehensive planning of limited value in government agencies and in private corporations involved in public policy making. A more effective approach to strategic planning and management must be based on an understanding of the political dynamics through which policies are made. It must adopt a variety of styles directly related to major functions in the policy making process and use a variety of political intervention and influence techniques that facilitate the implementation of plans and policies.     

The Role of Contract Expirations in Service Parts Management

The majority of after‐sales service providers manage their service parts inventory by focusing on the availability of service parts. This approach, combined with automatic replenishment systems, leads to reactive inventory control policies where base stock levels are adjusted only after a service contract expires. Consequently, service providers often face excess stock of critical service parts that are difficult to dispose due to their specificity. In this study, we address this problem by developing inventory control policies taking into account contract expirations. Our key idea is to reduce the base stock level of the one‐for‐one policy before obsolescence (a full or partial drop in demand rate) occurs and let demand take away excess stock. We refer to this policy as the single‐adjustment policy. We benchmark the single‐adjustment policy with the multiple‐adjustment policy (allowing multiple base stock adjustments) formulated as a dynamic program and verify that for a wide range of instances the single‐adjustment policy is an effective heuristic for the multiple‐adjustment policy. We also compare the single‐adjustment policy with the world‐dependent base stock policy offered by Song and Zipkin (1993) and identify the parameter combinations where both policies yield similar costs. We consider two special cases of the single‐adjustment policy where the base stock level is kept fixed or the base stock adjustment is postponed to the contract expiration time. We find that the initial demand rate, contract expiration time, and size of the drop in demand rate are the three key parameters driving the choice between the single‐adjustment policy and its special cases.     

A Probabilistic Analysis of the Passive–Restraint Question

The benefits and costs of automobile safety policies are compared using a methodology which explicitly quantifies the uncertainties. The policies addressed include both voluntary and compulsory manual belt usage, nondetachable passive (automatic) seat belts, and air bags. Estimates of the effectiveness and usage rates of these alternatives were obtained in the form of subjective probability distributions from eight experts. Their opinions were combined using equal weighting. The direct economic costs of the technologies were also estimated probabilistically. The number of lives saved and the net benefits of the policies were calculated probabilistically for a range of values of lifesaving. Probabilistic computations and sensitivity analysis were performed by the Demos modelling system using Monte Carlo simulation. The results are highly uncertain and quite sensitive to the value of lifesaving. Nevertheless, they imply that repeal of the passive-restraint standard is defensible according to the net-benefit criterion only if a relatively low value is assigned to lifesaving. The degree of uncertainty emphasizes the potential value of demonstration programs to obtain better information.     

转型期公共政策的价值定位:政府公共管理中功能转换的方向与悖论

中国社会的整体转型和全方位的现代化,政治文明建设的进一步推进,以及中国参与全球化进程和回应全球化的挑战,构成了中国公共政策转型的3个基本的前提和动力。公共政策本身在这一过程中也出现了转型,这给公共政策的价值定位和价值整合带来了更大的复杂性和困难性。由于社会转型的一个客观现象是不断以政策替代重塑公共管理,因此,在多元并存的公共政策价值中寻求平衡点的努力及其难度,决定了重塑中的政府公共管理必然是一种复合型的模式,这样,政府职能转变中出现很多悖论便是自然的现象。这是我们理解转型时期政府公共管理及其职能变迁的基础。     

Optimal repayment policies for multiple loans

This paper extends the applications of scheduling theory to certain problems in the area of finance. Specifically, a branch and bound algorithm to identify optimal repayment policies for multiple loans (credit purchases) has been developed. Each loan qualifies for a discount if it is paid on or before a certain date and a penalty is imposed if it is paid after its due date. These two dates are different in general. It is assumed that the cash for repayment is generated at a constant rate per day and it can be invested so that it continues to earn money until used for repayment. The objective is to minimize the present value of all future cash outflows.     

Liquidity planning in a small bank

Given a forecast of supply and demand for cash in each period of an infinite planning horizon, and with a known current portfolio, a policy is chosen to invest these cash supplies in securities of different maturities so that the demand in every future period can be satisfied by securities maturing in that period. The objective is to maximize the minimum of the excess over the planning horizon so that any illiquidity in one period is spread out over the entire planning horizon. Analytical solutions are obtained for single maturity and barbell investment policies. Feasibility and optimality conditions are determined for these policies.     

Fairness Among Servers When Capacity Decisions Are Endogenous

We look at a simple service system with two servers serving arriving jobs (single class). Our interest is in examining the effect of routing policies on servers when they care about fairness among themselves, and when they can endogenously choose capacities in response to the routing policy. Therefore, we study the two‐server game where the servers’ objective functions have a term explicitly modeling fairness. Moreover, we focus on four commonly seen policies that are from one general class. Theoretical results concerning the existence and uniqueness of the Nash equilibrium are proved for some policies. Further managerial insights are given based on simulation studies on servers’ equilibrium/off‐equilibrium behaviors and the resulting system efficiency performance under different policies.     

高科技企业的权力结构、权力博弈与治理效率

人力资本价值对高科技企业的发展至关重要,而人力资本团队价值进一步增加了高科技企业人力资本的权力竞争力,导致高科技企业权力结构与一般企业有所不同。高科技企业的权力结构与企业生命类型有关,对应于不同生命类型,高科技企业的权力结构不同,进而治理结构和治理形式也不同。提高企业的治理效率就必须根据企业自身生命特征有针对性地制定治理策略,只有这样才能提高企业的治理效率。     

A Newsvendor Problem with Revenue Sharing and Channel Coordination*

Increasingly manufacturers and retailers are implementing revenue‐sharing policies to coordinate distribution channels more effectively. This article considers a standard newsvendor problem in a single manufacturer–retailer channel and compares the expected profits that each party receives in a traditional ordering environment with those that can be achieved under a revenue‐sharing policy designed to completely eliminate double marginalization. It is shown that the retailer always benefits from the transition to revenue sharing by capturing a portion of the incremental channel profit generated by the complete elimination of double marginalization. A necessary demand‐distribution‐dependent condition is derived under which the transition to revenue sharing benefits the manufacturer as well. The findings of this research are illustrated in a numerical example for the uniform demand distribution.     

Retailer's Response to Alternate Manufacturer's Incentives Under a Single‐Period,Price‐Dependent,Stochastic‐Demand Framework*

This article considers the joint development of the optimal pricing and ordering policies of a profit‐maximizing retailer, faced with (i) a manufacturer trade incentive in the form of a price discount for itself or a rebate directly to the end customer; (ii) a stochastic consumer demand dependent upon the magnitude of the selling price and of the trade incentive, that is contrasted with a riskless demand, which is the expected value of the stochastic demand; and (iii) a single‐period newsvendor‐type framework. Additional analysis includes the development of equal profit policies in either form of trade incentive, an assessment of the conditions under which a one‐dollar discount is more profitable than a one‐dollar rebate, and an evaluation of the impact upon the retailer‐expected profits of changes in either incentive or in the degree of demand uncertainty. A numerical example highlights the main features of the model. The analytical and numerical results clearly show that, as compared to the results for the riskless demand, dealing with uncertainty through a stochastic demand leads to (i) (lower) higher retail prices if additive (multiplicative) error, (ii) lower (higher) pass throughs if additive (multiplicative) error, (iii) higher claw backs in both error structures wherever applicable, and (iv) higher rebates to achieve equivalent profits in both error structures.     

On the Issuing Policies for Perishable Items such as Red Blood Cells and Platelets in Blood Service

Red blood cells (RBCs) and platelets are examples of perishable items with a fixed shelf life. Recent studies show that transfusing fresh RBCs may lead to an improvement of patient outcomes. In addition, to better manage their inventory, hospitals prefer to receive fresh RBCs and platelets. Therefore, as well as minimizing outdates and shortages, reducing the average age of issue is a key performance criterion for blood banks. The issuing policy in a perishable inventory system has a substantial impact on the age of issue and outdate and shortage rates. Although several studies have compared the last in first out (LIFO) and the first in first out (FIFO) policies for perishable products, only a few studies have considered the situation of blood banks where replenishment is not controllable. In this study, we examine various issuing policies for a perishable inventory system with uncontrollable replenishment, and outline a modified FIFO policy. Our proposed modified FIFO policy partitions the inventory into two parts such that the first part holds the items with age less than a threshold. It then applies the FIFO policy in each part and the LIFO policy between the parts. We present two approximation techniques to estimate the average age of issue, the average time between successive outdates and the average time between successive shortages of the modified FIFO policy. Our analysis shows in several cases that where the objective function is a single economic function, or it is formulated as a multiobjective model, the modified FIFO policy outperforms the FIFO and LIFO policies.     

经济增长和环境质量相容性政策条件——环境技术进步方向视角下的政策偏向效应检验

现有文献关注政策规制的经济与环境绩效,却并未重视不同类型政策的技术偏向,以及技术偏态情境中经济增长和环境质量相容发展的政策条件。本文扩展Acemoglu等(2012)的环境技术进步方向模型,数理演绎不同性质政策的技术偏向,以及技术进步方向转变时经济增长和环境质量的动态演化过程,再结合我国经济数据进行政策效果评价。研究结果发现:(1)环境技术进步方向是技术研发效率和环境政策累积作用的结果,环境政策会通过影响不同类型技术创新激励的方式,改变环境技术进步方向。(2)异质性政策转变技术进步方向,影响经济增长和环境质量,其作用存在不同的着力点和偏向性。其中,研发补贴政策的清洁技术偏向和产出激励效果明显,而规制类政策的环境质量效应优于研发补贴,但其对经济增长的作用表现出非线性U型特征。(3)单一政策干预往往难以破除经济增长和环境质量的两难困境,而政策组合的效果明显优于单一政策,特别是在碳排放权交易试点地区实施研发补贴政策,以及在碳排放权交易试点地区同时实行环境税与研发补贴,效果明显优于实施单一政策。但最优的政策组合并非固定不变,而往往处于动态变化过程中。