一种新的三角模糊数型多属性决策方法

针对模糊群体多属性决策问题,提出一种模糊群体多属性决策方法．首先,定义了任意专家的中心决策矩阵;其次,利用任意2个规范化决策矩阵之间的相似度获得专家的综合重要性程度;再次,通过专家的综合重要性程度得到方案的平均可信度,进而得到方案的排序结果;最后,实例分析表明了所提出方法的可行性和有效性．     

基于模糊多属性决策的多维时序信用风险评价建模

针对属性权重完全未知且数据为多维时序的信用风险评价问题,提出基于多属性决策与模糊聚类相结合的混杂信用风险评价建模方法.该方法使用离差最大化方法和二次规划模型得出指标属性的综合权重,对受评样本在各时点上进行多属性决策得到决策评分,再通过决策评分矩阵进行模糊聚类,并对结果进行了有效性验证.最后通过实例验证,证明该方法具有可行性和有效性.     

A theoretical and empirical investigation of multi‐item on‐line auctions

In this paper we explore and analyze the structure of Internet auctions from an analytical and an empirical perspective. Such web‐based auctions are rapidly emerging as a mercantile process of choice in the electronic marketplace. We observe current Internet auctions for one‐time products, such as rapidly aging hardware, and analyze them within the framework of the existing auction theory. While traditional auction theory focuses on single‐item auctions, we observe that a majority of on‐line auctions are multi‐item auctions. A significant contribution of this work is the theoretical derivation of the structure of the winning bids in multi‐item progressive on‐line auctions. Additionally, for comparative purposes, we explore the structural characteristics of alternative multi‐item auction mechanisms proposed in the auction theory. We derive hypotheses based on our analytical results and compare two different types of auction mechanisms. We test the traditional auction theory assumption regarding the homogeneity of bidders and present the first ever empirically derived classification and performance‐comparison of on‐line bidders. We test our hypotheses using real‐world empirical data obtained by tracking a premier web‐based auction site. Statistical analysis of the data indicates that firms may gain by choosing alternative auction mechanisms. We also provide directions for further exploration of this emerging but important dimension of electronic commerce. This revised version was published online in July 2006 with corrections to the Cover Date.     

一种面向政府采购的多属性反向拍卖模型

为了对政府采购中电子反向拍卖系统的适用性进行改善.利用多属性决策理论和相关算法,对多属性反向拍卖的步骤和模型进行研究.对只按价格来选取供应商的方式进行了改进,建立了多属性选取供应商的反向拍卖系统.系统实现了选取供应商的自动化,能达到综合属性的最优,满足政府采购中以反拍方式进行采购的需求,提高了采购效率,降低了采购成本.     

FAIRNESS IN RECURRENT AUCTIONS WITH COMPETING MARKETS AND SUPPLY FLUCTUATIONS

Auctions have been used to deal with resource allocation in multiagent environments, especially in service‐oriented electronic markets. In this type of market, resources are perishable and auctions are repeated over time with the same or a very similar set of agents. In this scenario it is advisable to use recurrent auctions: a sequence of auctions of any kind where the result of one auction may influence the following one. Some problems do appear in these situations, as for instance, the bidder drop problem, the asymmetric balance of negotiation power or resource waste, which could cause the market to collapse. Fair mechanisms can be useful to minimize the effects of these problems. With this aim, we have analyzed four previous fair mechanisms under dynamic scenarios and we have proposed a new one that takes into account changes in the supply as well as the presence of alternative marketplaces. We experimentally show how the new mechanism presents a higher average performance under all simulated conditions, resulting in a higher profit for the auctioneer than with the previous ones, and in most cases avoiding the waste of resources.     

基于多属性特征胎记的软件盗版检测

针对传统单属性特征在抗攻击性和检测率方面的不足,提出了基于分类多属性特征的软件盗版检测算法。通过对等价语义变换后的软件集合进行静态分析、提取过滤、分割和度量,最后按相似度构造分类器,在低开销下综合判别未知软件版本信息。给出了算法的描述,刻画了算法的实现过程,实验结果表明,该算法在提高判别的鲁棒性、可信度和抗攻击方面具有适用性,与同类方法比较也具有明显优势。     

基于含虚拟卖家组合双向拍卖的网格资源管理

考虑到组合双向拍卖与网格资源选择过程存在较高相似性,提出基于组合双向拍卖的网格资源管理方案,建立了具体的包含虚拟卖家的多回合组合双向拍卖机制。在该机制中,采用一种动态报价策略以提高拍卖交易率,同时通过引入虚拟卖家,将竞卖成功者的剩余资源转化为交易剩余,不仅提高了资源利用率,而且扩大了拍卖的交易剩余,从而促进形成良好的经济激励,使更多的网格用户和网格资源加入到网格交易中。     

投标者为风险规避型引入佣金的分析(二)

在投标者是风险规避型的情况下,考虑引入佣金对拍卖结果的影响,在关联价值模型中,对于密封一价拍卖和密封二价拍卖,佣金比例k越高投标者的报价越低,卖方的期望收益越低,拍卖行的期望收益越高,但投标者的期望效用与k无关。在对称独立私有价值模型中,当引入佣金时,收益等价性原理不成立,卖方在一价拍卖下的期望收益比在二价拍卖下的收益要高。     

投标者为风险规避型引入佣金的分析(一)

在投标者为风险规避型的情况下,考虑引入佣金对拍卖结果的影响,发现在对称独立私有价值模型中,对于密封一价拍卖和密封二价拍卖,佣金比例k越大,则投标者的报价越低,卖方的期望收益越少,拍卖行的期望收益越大,但投标者的期望效用与k无关。     

基于分式规划的区间直觉梯形模糊数多属性决策方法

针对属性值为区间梯形直觉模糊且属性权重为区间数的多属性决策问题,提出一种基于分式规划的决策方法.定义了区间梯形直觉模糊数的Hamming距离和Euclidean距离,采用优劣解距离法构建了相对贴近度的非线性分式规划模型,并通过Charnes and Cooper变换转化为线性规划模型求解,得到各方案相对贴近度的区间数,进而提出了决策方法.数值算例分析验证了所提出方法的有效性.