考虑相互依赖性的信息系统安全投资及协调机制

考虑信息系统安全相互依赖情形下最优化信息系统连续时间安全投资水平是一个值得研究的问题。首先讨论了非合作博弈下信息系统安全投资的最优策略选择,在此基础上讨论了安全投资效率参数、黑客学习能力、传染风险对信息系统脆弱性及信息系统安全投资率的影响。其次,在推导出两企业在合作博弈情形下最优策略选择的基础上,对比两种情形下的博弈均衡结果,得出合作博弈下的投资水平高于非合作博弈下的投资水平。原因是两个企业的相互依赖关系隐含着企业投资的负外部性,从而导致企业投资不足。最后,构建一种双边支付激励机制消除企业投资不足问题,从而使企业达到合作博弈下的最优投资水平,提高两个企业的收益。     

考虑延迟现象的质量改进投入和营销努力动态协同策略

利用时滞微分方程刻画质量改进投入对品牌商誉提升的延迟现象,分别构建了制造商和零售商采取非合作博弈、合作博弈以及成本分担的部分合作博弈(制造商参与营销的单向部分合作博弈、零售商参与生产的单向部分合作博弈、制造商参与营销及零售商参与生产的双向部分合作博弈)五种决策模式下的微分博弈模型。借助哈密尔顿极大值原理,求解得到五种情形下的制造商最优质量改进投入策略和零售商的最优营销努力策略以及供应链利润。对比五种博弈模式下的结果发现:1)延时现象会降低制造商进行质量改进投入的积极性,但对零售商营销努力无影响;品牌商誉在延迟现象影响下出现先衰减后提升的演进规律;2)合作博弈对于供应链绩效总是最优的,三种成本分担的部分合作博弈契约虽不能实现供应链的完全协调,但可以对非合作博弈情形进行帕累托改进;3)对比两种单向部分合作博弈,在提高供应链利润方面,制造商参与营销的成本分担契约优于零售商参与生产的成本分担契约;4)三种成本分担契约中,双向合作的部分合作博弈是供应链的最优选择,但随着延迟时间增大,其帕累托改进效果将不再明显。     

A game-theoretic analysis of information sharing and security investment for complementary firms

This paper investigates information sharing and security investments by two firms provided that their information assets are complementary in the sense that their combined information assets are of significant value, whereas the information asset of a single firm is no value to an attacker. In particular, assuming that each firm chooses its security investment and information sharing individually, we obtain some insights about the optimal choices for the firms and the attacker, which form sharp comparisons with those derived from common (substitutive) firms. We further analyse the effect of a social planner on social total costs by assuming that it can control security investments, information sharing and both of them respectively. We demonstrate that an increase in intervention by the social planner may not necessarily be preferable.     

Profit allocation games in supply chains

The paper considers a supply chain where a number of agents are connected in some network relationship. Game theory is a very powerful framework for studying decision making problems, involving a group of agents in a supply chain. Allocation games examine the allocation of value among agents connected by a network. The ongoing actions in the supply chain are a mix of cooperative and non-cooperative behavior of the participants. The paper proposes a two-stage procedure for profit allocation based on combination of non-cooperative and cooperative game approaches. In the first stage, retailers meet customer price-dependent stochastic demand and seek to maximize total profit from the sale. Retailers are trying to align goals with producers on a contract basis and share the total profit with them. In the second stage, the cooperating producers allocate individual profits.     

Non-cooperative joint replenishment under asymmetric information

We consider jointly replenishing n ex-ante identical firms that operate under an EOQ like setting using a non-cooperative game under asymmetric information. In this game, each firm, upon being privately informed about its demand rate (or inventory cost rate), submits a private contribution to an intermediary that specifies how much it is willing to pay for its replenishment per unit of time and the intermediary determines the maximum feasible frequency for the joint orders that would finance the fixed replenishment cost. We show that a Bayesian Nash equilibrium exists and characterize the equilibrium in this game. We also show that the contributions are monotone increasing in each firm’s type. We finally conduct a numerical study to compare the equilibrium to solutions obtained under independent and cooperative ordering, and under full information. The results show that while information asymmetry eliminates free-riding in the contributions game, the resulting aggregate contributions are not as high as under full information, leading to higher aggregate costs.     

Profit maximizing coalitions with shared capacities in distribution networks

We study the distribution network structure of multiple firms in the context of demand sensitivity to market offers. The problem consists in determining the profitability of horizontal collaboration between firms in a collaborative distribution schema. It considers the case of a set of regional distribution centers (DCs) where each DC is initially dedicated solely to one firm’s distribution activities and studies when it is beneficial that the DC owners collaborate through sharing their storage-throughput capacity. Such strategic decisions are made in order to improve the distribution capabilities of firms in terms of response time and cost-efficiency compared to the stand-alone situation. The problem is modeled as a coalition formation game in a cooperative framework, and we propose a collaborative distribution game with profit maximization. Three sharing mechanisms are modeled and tested: egalitarian allocation, proportional allocation, and Shapley value. The collaboration decision conditions for a given firm are analytically derived according to the sharing method considered and used to enhance the solution approach. Our numerical results clearly highlight the impact of this innovative collaboration opportunity on the firms’ performance in terms of distribution cost savings and revenue increases. An observed behavior is that the formation of several sub-coalitions prevails over the formation of a grand coalition, and that different cost sharing methods can lead to different sub-coalitions. We also provide managerial insights on the appropriate size of a coalition in various business instances tested, and on the key drivers that foster horizontal collaborative behavior among firms.     

医药产学研联盟创新决策、创新危机与利润分配

以我国医药行业产学研合作创新为现实背景,构建两家相互竞争的制药企业与学研机构的双边纳什议价模型,分析企业的创新价值和议价能力对联盟成员绩效的影响,探讨合作创新对药品价格、企业市场份额、经营绩效和社会福利的影响,研究制药企业创新战略的选择决策及创新对企业可能的危险。通过模型分析,得到如下结论:产学研合作创新能够提高社会总福利,但不一定提高制药企业的绩效和药品的价格;议价能力强的制药企业不一定总是获得高利润,企业最终的利润受到企业自身及竞争者的议价能力、创新价值的共同影响;虽然产品创新能够提高消费者的购买意愿,但盲目跟风创新可能会带来双输的结果。本研究对促进医药行业的产学研合作,提高产学研合作的有效性具有现实意义。     

Cooperative games of choosing partners and forming coalitions in the marketplace

Two games of interacting between a coalition of players in a marketplace and the residual players acting there are discussed, along with two approaches to fair imputation of gains of coalitions in cooperative games that are based on the concepts of the Shapley vector and core of a cooperative game. In the first game, which is an antagonistic one, the residual players try to minimize the coalition's gain, whereas in the second game, which is a noncooperative one, they try to maximize their own gain as a coalition. A meaningful interpretation of possible relations between gains and Nash equilibrium strategies in both games considered as those played between a coalition of firms and its surrounding in a particular marketplace in the framework of two classes of n-person games is presented. A particular class of games of choosing partners and forming coalitions in which models of firms operating in the marketplace are those with linear constraints and utility functions being sums of linear and bilinear functions of two corresponding vector arguments is analyzed, and a set of maximin problems on polyhedral sets of connected strategies which the problem of choosing a coalition for a particular firm is reducible to are formulated based on the firm models of the considered kind.     

风险中性零售商的合作广告策略与订货模型

考虑了由一个制造商与一个零售商构成的单期二阶段供应链是否进行合作广告的博弈问题.面对市场需求的不确定性,零售商从制造商处订购报童类型产品销售给消费者,零售商具有风险中性的行为特征.通过不合作广告与合作广告两种情形,制造商与零售商进Stackelberg主从博弈,得到了均衡解,比较后发现,合作广告下的最优解及利润总是优于不合作广告下的最优解和利润,告诉了上下游企业采用合作广告的广告策略.最后,通过数值算例,给出了需求敏感系数对最优决策的影响,同时也论证了有关结论.     

A game theoretic approach to coordinate pricing and vertical co-op advertising in manufacturer-retailer supply chains

Vertical cooperative (co-op) advertising is a marketing strategy in which the retailer runs local advertising and the manufacturer pays for a portion of its entire costs. This paper considers vertical co-op advertising along with pricing decisions in a supply chain; this consists of one manufacturer and one retailer where demand is influenced by both price and advertisement. Four game-theoretic models are established in order to study the effect of supply chain power balance on the optimal decisions of supply chain members. Comparisons and insights are developed. These embrace three non-cooperative games including Nash, Stackelberg-manufacturer and Stackelberg-retailer, and one cooperative game. In the latter case, both the manufacturer and the retailer reach the highest profit level; subsequently, the feasibility of bargaining game is discussed in a bid to determine a scheme to share the extra joint profit.     

On the cooperation of recycling operations

This paper addresses two important issues that may affect the operations efficiency in the recycling industry. First, the industry contains many small-scale and inefficient recycling firms, especially in developing countries. Second, the output from recycling a waste product often yields multiple recycled products that cannot all be sold efficiently by a single firm. To address these two issues, this paper examines how different firms can cooperate in their recycling and pricing decisions using cooperative game theory. Recycling operations under both joint and individual productions with different cost structures are considered. Decisions include the quantity of waste product to recycle and the price at which to sell each recycled product on each firm’s market. These decisions can be made jointly by multiple cooperating firms to maximize total profit. We design allocation schemes for maximized total profit to encourage cooperation among all firms. Managerial insights are provided from both environmental and economic perspectives.     

On channel coordination through revenue-sharing contracts with price and shelf-space dependent demand

This paper deals with the problem of coordinating a vertically separated channel under a consignment contract with revenue sharing. We consider the demand of the downstream player, e.g., the retailer, being price and shelf-space sensitive. Under such a setting, the retailer decides on the revenue-sharing percentage and the slotting fee. And the upstream player, e.g., the manufacturer, decides on the retail price and the size of shelf-space. For each item sold, the retailer deducts an agreed-upon percentage from the selling price and remits the balance to the manufacturer. We model the decision-making of the two firms as a Stackelberg game, and carry out equilibrium analysis for both the centralized and decentralized regimes of the channel, with and without cooperation. In addition, a profit sharing scheme through a two-part slotting allowance is proposed, which leads to Pareto improvements among channel participants. Our analysis reveals that the non-cooperative game tends to set a higher revenue-sharing percentage and lower slotting fee by the retailer, and a higher retail price and less display space by the manufacturer, which leads to a lower channel profit. The consistent bias can be perfectly rectified by the cooperative game through the proposed two-part contractual agreement.     

产业集群协同创新知识共享策略的微分博弈研究

针对产业集群协同创新中核心企业和配套企业的知识共享问题, 通过构建微分博弈模型, 运用HJB方程分别考察三种知识共享博弈情形下核心企业和配套企业的最优知识共享策略。通过三种博弈结果的比较分析发现:Stackelberg主从博弈情形下, 知识共享投入补贴作为一种激励策略可促进配套企业知识共享意愿、双方各自知识共享收益以及双方知识共享总收益均优于Nash非合作情形;协同合作博弈情形下双方各自知识共享意愿、各自知识共享收益和双方知识共享总收益均优于非合作情形, 且收益分配系数α存在一个阈值, 可实现双方个体收益的帕累托最优。最后, 通过数值算例分析验证了理论推导的结果。     

Survey of cooperative inventory games and extensions

We examine cooperative games in supply-chain management termed Inventory Games. Supply-chain management has non-cooperative and cooperative interactions between the participating players. We provide a concise survey of cooperative inventory games in the form of extensions on two basic problems. For deterministic games, Economic Order Quantity-like policies with joint replenishment are of primary interest. For stochastic games we examine Newsvendor-like centralization games and their extensions. We conclude with a short summary of a dynamic Newsvendor realization game and directions for further research.     

Research on coordination mechanism in three-level green supply chain under non-cooperative game

In view of the three-level green supply chain system in which market demand correlates with product green degree, game theory is applied to study four models, namely cooperative decision-making, three-level leader–follower game, Stackelberg game I and Stackelberg game II. Theoretical analysis shows that the profits of both the supply chain system and participating members reach the optimal level under cooperative decision-making, while the decision results of participating members as well as the channel profit are far from satisfactory under the non-cooperative game. By building a revenue sharing mechanism, Shapley value method coordination mechanism and asymmetric Nash negotiation mechanism, supply chain members are motivated to respond positively to the cooperation in producing and marketing green products, the optimal income distribution coefficient of participating members is given, and the income of each member is increased substantially as is compared with that under the non-cooperative game. Also, by determining the cooperative parameter, green supply chain managers may effectively get involved in the aforementioned coordination mechanisms to intervene and regulate the green channel so as to promote the smooth operation of green supply chain.     

On the population monotonicity of independent set games

An independent set game is a cooperative game dealing with profit sharing in the maximum independent set problem. A population monotonic allocation scheme is a rule specifying how to share the profit of each coalition among its participants such that every participant is better off when the coalition expands. In this paper, we provide a necessary and sufficient characterization for independent set games admitting population monotonic allocation schemes. Moreover, our characterization can be verified efficiently.     

A nonlinear Cournot duopoly with advertising

This paper aims at studying local and global dynamics in a nonlinear duopoly with quantity-setting firms and non-cooperative advertising investments that affect the degree of (horizontally) differentiated products. It concentrates on persuasive advertising in a model where each firm has limited information and uses a behavioural rule to set the quantity for the subsequent period. By using some mathematical techniques and numerical simulations, our results show the existence of weak (à la Milnor) attractors, multistability and chaotic dynamics. In the long term, firms may continuously shift from states in which they invest in advertising to states in which advertising investment is absent.     

Effects of asymmetric knowledge spillovers on the stability of horizontal and vertical R&D cooperation

In order to investigate the role of asymmetric spillovers in the stability of R&D cooperation, this paper distinguishes two different types of cooperative partners, and uses a game theory approach to reveal the relationship between asymmetric spillovers and R&D investment in the horizontally and vertically related R&D cooperation. In the horizontal R&D cooperation, higher incoming spillovers and lower outgoing spillovers induce firms to invest on R&D efforts as agreed. However, it is the contradiction between horizontal firms’ attitudes towards asymmetric spillovers that leads to the inherent instability of the cooperation. In the vertical R&D cooperation, our results question the usually held opinion about the effects of asymmetric spillovers on the decision of R&D investment. The incoming spillovers are less important in the innovation process for vertically related R&D cooperation. A firm tends to under-invest on the arranged level of R&D efforts when its incoming spillovers increase. Our results also show that efficient mechanisms to restrain firms’ non-cooperative behavior are essential to improve the stability of horizontal and vertical R&D cooperation.     

基于微分博弈的二级猪肉供应链质量行为协调机制研究

运用微分博弈方法研究了由单一生猪屠宰加工企业和单一超市构成的二级猪肉供应链质量行为协调机制。首先考察并比较了Nash非合作博弈、Stackelberg主从博弈以及协同合作博弈情形下屠宰加工企业和超市的最优质量行为决策,研究结果表明协同合作决策模式下,屠宰加工企业和超市的质量行为以及猪肉供应链总体利润均严格优于在非合作决策模式下的相应值。然后导出了能够使屠宰加工企业和超市的个体利润达到帕累托最优,进而实现双方质量行为协调的供应链总体利润分配系数的取值范围。     

On the value of information sharing and cooperative price setting

We consider a setting of two firms that sell substitutable products under price competition. We show that private signals enable firms to improve market forecast and earn higher profits. Provided that their private signals are not perfectly correlated, firms can benefit from sharing signals with each other. This is irrespective of product substitutability. Moreover, information sharing is a strategic complement to cooperative price setting to improve the profit performance of firms.