区间合作对策核心存在性的进一步讨论

区间合作对策,是研究当联盟收益值为区间数情形时如何进行合理收益分配的数学模型。近年来,其解的存在性与合理性等问题引起了国内外专家的广泛关注。区间核心,是区间合作对策中一个非常稳定的集值解概念。本文首先针对区间核心的存在性进行深入的讨论,通过引入强非均衡,极小强均衡,模单调等概念,从不同角度给出判别区间核心存在性的充分条件。其次,通过引入相关参数,定义了广义区间核心,并给出定理讨论了区间核心与广义区间核心的存在关系。本文的结论将为进一步推动区间合作对策的发展,为解决区间不确定情形下的收益分配问题奠定理论基础。     

Cores and large cores when population varies

In a TU cooperative game with populationN, a monotonic core allocation allocates each surplusv (S) among the agents of coalitionS in such a way that agenti's share never decreases when the coalition to which he belongs expands.We investigate the property of largeness (Sharkey [1982]) for monotonic cores. We show the following result. Given a convex TU game and an upper bound on each agent' share in each coalition containing him, if the upper bound depends only upon the size of the coalition and varies monotonically as the size increases, then there exists a monotonic core allocation meeting this system of upper bounds. We apply this result to the provision of a public good problem.     

基于Choquet积分形式的模糊联盟核心

在具有联盟结构的合作对策中,针对局中人以某种程度参与到合作中的情况,研究了模糊联盟结构的合作对策的收益分配问题。首先,定义了具有模糊联盟结构的合作对策及相关概念。其次,定义了Choquet积分形式的模糊联盟核心,提出了该核心与联盟核心之间的关系,对于强凸联盟对策,证明Choquet积分形式的模糊Owen值属于其所对应的模糊联盟核心。最后通过算例,对该分配模型的可行性进行分析。     

残缺区间合作博弈及其在农地污染治理中的应用

针对联盟收益值部分未知的区间合作博弈,定义了残缺区间合作博弈的相关概念。基于合作博弈的超可加性,建立了联盟区间收益值的一致性验证模型。通过构造正、负理想分配及其与收益分配向量之间的偏差,给出了残缺区间合作博弈的区间Ideal-Shapley值求解模型,分析了区间Ideal-Shapley值的合理性与存在性。利用上述模型求解农地污染联合治理的节约成本分摊策略,验证了区间Ideal-Shapley值求解模型的有效性。     

基于联盟结构的模糊合作博弈的收益分配方案

研究了具有联盟结构的企业联盟模糊情况下各局中人的收益分配问题.首先拓展了Owen联盟值在经典意义下满足的5个公理,利用Choquet积分给出了基于联盟结构的模糊合作博弈的Owen联盟值,即模糊Owen联盟值的具体形式,并证明该联盟值满足新定义的5个公理.最后用实例验证了模糊Owen联盟值方法,并对计算结果进行分析。     

Inventory games with permissible delay in payments

Meca et al. (2004) studied a class of inventory games which arise when a group of retailers who observe demand for a common item decide to cooperate and make joint orders with the EOQ policy. In this paper, we extend their model to the situation where retailer’s delay in payments is permitted by the supplier. We introduce the corresponding inventory game with permissible delay in payments, and prove that its core is nonempty. Then, a core allocation rule is proposed which can be reached through population monotonic allocation scheme. Under this allocation rule, the grand coalition is shown to be stable from a farsighted point of view.     

STRUCTURES OF VALUES FOR SET GAMES RESTRICTED BY PARTITION SYSTEM

§1IntroductionA cooperative game with transferable utility(TU)is a pair(N,v),where N is anonempty,finite set and v∶2N→R is a characteristic function defined on the power set ofN satisfying v()∶=0.LetCGdenote the set of all cooperative TU-games with anarbitrary player set.An element of N(notation:i∈N)and a nonempty subset S of N(notation:S N or S∈2Nwith S≠)are called a player and coalition respectively,andthe associated real number v(S)is called the worth of coalition S to be in…     

A bargaining set for monotonic simple games based on external and internal stability

A new bargaining set based on notions of both internal and external stability is developed in the context of endogenous coalition formation. It allows one to make an explicit distinction between within-group and outside-group deviation options. This type of distinction is not present in current bargaining sets. For the class of monotonic proper simple games, the outcomes in the bargaining set are characterized. Furthermore, it is shown that the bargaining set of any homogeneous weighted majority game contains an outcome for which the underlying coalition structure consists of a minimal winning coalition and its complement.     

Game-theoretic analysis of cooperation among supply chain agents: Review and extensions

This paper surveys some applications of cooperative game theory to supply chain management. Special emphasis is placed on two important aspects of cooperative games: profit allocation and stability. The paper first describes the construction of the set of feasible outcomes in commonly seen supply chain models, and then uses cooperative bargaining models to find allocations of the profit pie between supply chain partners. In doing so, several models are analyzed and surveyed, and include suppliers selling to competing retailers, and assemblers negotiating with component manufacturers selling complementary components. The second part of the paper discusses the issue of coalition formation among supply chain partners. An exhaustive survey of commonly used stability concepts is presented. Further, new ideas such as farsightedness among supply chain players are also discussed and analyzed. The paper also opens some avenues of future research in applying cooperative game theory to supply chain management.     

最短路博弈群体单调分配方案构造

群体单调分配方案(Population Monotonic Allocation Scheme, 后简称PMAS)是合作博弈的一类分配机制。在合作博弈中, PMAS为每一个子博弈提供一个满足群体单调性的核中的分配方案, 从而保证大联盟的动态稳定性。本文主要贡献为利用线性规划与对偶理论构造与求解一类基于最短路问题的合作博弈(最短路博弈)的PMAS。我们首先借助对偶理论, 利用组合方法为最短路博弈构造了一个基于平均分摊思想的PMAS。然后借鉴计算核仁的Maschler方案, 将PMAS的存在性问题转化为一个指数规模的线性规划的求解问题, 并通过巧妙的求解得到了与之前组合方法相同的最短路博弈的PMAS。     

最短路博弈群体单调分配方案构造

群体单调分配方案(Population Monotonic Allocation Scheme, 后简称PMAS)是合作博弈的一类分配机制。在合作博弈中, PMAS为每一个子博弈提供一个满足群体单调性的核中的分配方案, 从而保证大联盟的动态稳定性。本文主要贡献为利用线性规划与对偶理论构造与求解一类基于最短路问题的合作博弈(最短路博弈)的PMAS。我们首先借助对偶理论, 利用组合方法为最短路博弈构造了一个基于平均分摊思想的PMAS。然后借鉴计算核仁的Maschler方案, 将PMAS的存在性问题转化为一个指数规模的线性规划的求解问题, 并通过巧妙的求解得到了与之前组合方法相同的最短路博弈的PMAS。     

Complexity of core allocation for the bin packing game

This paper provides complexity results and develops optimal algorithms for core membership and emptiness tests of the bin packing game. Our algorithms find the maximum surplus profit, the least integer core value, and the minimum value required by the grand coalition for the existence of an integer core allocation.     

Population Monotonic Allocation Schemes in Bankruptcy Games

The USA Bankruptcy Code legislates the bankruptcy of firms. Any allocation mechanism that is legal according to the Bankruptcy Code is necessarily population monotonic. Bankruptcy rules yielding a population monotonic allocation scheme in the associated bankruptcy game are characterized by efficiency, reasonability (each claimant receives a nonnegative amount not exceeding his claim), and the thieve property. The thieve property for bankruptcy problems entails that if a claimant manages to escape with his claim, the amount allocated to each remaining claimant is not larger than his share in the original problem. Many bankruptcy rules studied in the literature are efficient, reasonable, self-consistent, and monotonic. Rules satisfying these axioms are shown to yield population monotonic allocation schemes.     

一种资源投入不确定情形下的合作博弈形式及收益分配策略

首先,将经典合作博弈进行扩展,提出了一类模糊联盟合作博弈的通用形式,涵盖常见三种模糊联盟合作博弈,即多线性扩展博弈、比例模糊博弈与Choquet积分模糊博弈.比例模糊博弈、Choquet积分模糊博弈的Shapley值均可以作为一种特定形式下模糊联盟合作博弈的收益分配策略,但是对于多线性扩展博弈的Shapley值一直关注较少,因此利用经典Shapley值构造出多线性扩展博弈的Shapley值,以此作为一种收益分配策略.最后,通过实例分析了常见三类模糊联盟合作博弈的形式及其对应的分配策略,分析收益最大的模糊联盟合作对策形式及最优分配策略,为不确定情形下的合作问题提供了一定的收益分配依据.     

Designing coalition-based fair and stable pricing mechanisms under private information on consumers’ reservation prices

We model the relation between an aggregator and consumers joining a coalition to reduce the risk resulting from the unpredictability of their base load demand, as a Stackelberg game formulated as a mathematical bilevel program with private information on the consumers’ reservation prices. At the upper-level of the Stackelberg game, the aggregator optimizes his daily price profile so as to reach a net targeted profit which is the maximum value guaranteeing that no consumer will leave the coalition - to contract with a conventional retailer considered here as a fixed alternative - while meeting fairness criterion imposed by the cost-sharing mechanism. At the lower-level, the consumers are asked to provide in day ahead an estimate of their base load hourly demand profile and to schedule their shiftable loads depending on the price signal sent by the aggregator. We provide algorithms that determine the unique price profile and consumer shiftable load schedules as functions of the reservation price estimates. The Stackelberg game between the aggregator and the consumers being repeated for a period of time, the aggregator has the possibility to update his estimates of the reservation prices relying on a feedback function which depends on the percentage of activated loads. A randomized algorithm for consumers’ reservation price learning based on regret minimization is provided. For four cost-sharing mechanisms such as uniform allocation, stand-alone cost, Shapley value, separable and non-separable costs, we determine the closed form of the aggregator’s optimal net targeted profit guaranteeing the stability of the coalition. We also determine conditions guaranteeing the core non-emptiness and prove that for a profit-maximizing aggregator, the stand-alone cost is always preferable to the Shapley value, which coincides with the uniform allocation. Furthermore, the optimal size of the coalition - in terms of the aggregator’s profit - can be determined analytically when the Shapley value is implemented as cost-sharing mechanism. The results are illustrated on a case study where we show that there exists an optimal net targeted profit below which the consumers energy bill is lower when joining the aggregator than with the conventional retailer. Coalition dynamics is also analyzed numerically depending on the consumer inertia in their energy supplier choice process, for each cost-sharing mechanism.     

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.     

具有区间支付的宗派对策

在区间不确定环境下,针对具有否决权的成员与其他成员之间的合作,建立了具有区间支付的宗派对策。在区间核心中,非宗派成员得到的区间分配不能超过他对大联盟的边际贡献。给出了完全区间宗派对策的等价条件。当相应的区间减法可行时,完全区间宗派对策的区间核心中的分配可以通过两种单调区间分配方案扩张得到。算例验证了模型的有效性。     

Convex and exact games with non-transferable utility

We generalize exactness to games with non-transferable utility (NTU). A game is exact if for each coalition there is a core allocation on the boundary of its payoff set.     

Inheritance of properties in communication situations

In this paper we consider cooperative games in which the possibilities for cooperation between the players are restricted because communication between the players is restricted. The bilateral communication possibilities are modeled by means of a (communication) graph. We are interested in how the communication restrictions influence the game. In particular, we investigate what conditions on the communication graph guarantee that certain appealing properties of the original game are inherited by the graph-restricted game, the game that arises once the communication restrictions are taken into account. We study inheritance of the following properties: average convexity, inclusion of the Shapley value in the core, inclusion of the Shapley values of a game and all its subgames in the corresponding cores, existence of a population monotonic allocation scheme, and the property that the extended Shapley value is a population monotonic allocation scheme. Received May 1998/Revised version January 2000