M-G-P型复杂网络中有寿命节点的进入退出机制

现实中复杂网络结构复杂,形式多样,处在高度动态变化的过程.为了更好地理解真实网络的演化,基于复杂网络的特性进行分析,建立了Poissotn连续时间增长节点具有寿命的M-G-P型复杂网络模型,模型中包括:新节点加入、节点老化和老节点退出等,基于齐次马尔可夫链对模型的度分布进行计算,得出M-G-P型网络的度分布符合幂律分布,模型和BA模型一样能产生指数γ=3的无标度网络,验证了导致无标度网络度分布特征起关键性作用的是链接的偏好特性.     

基于网络结构的高维协方差矩阵估计

本文在Lan等~([1])利用网络结构对连续变量协方差矩阵进行估计的研究基础上进行改进和扩展,给出一种基于网络结构的高维协方差矩阵估计方法,并允许响应变量异方差性存在.该方法将高维协方差矩阵的估计问题转化为关于网络结构的低维线性回归的参数估计问题,从而极大减少了计算量.在有限样本甚至n=1的情况下,该估计方法仍然适用,且估计效果会随着矩阵维数的增大而提高.此外,本文给出一种利用协方差矩阵识别网络中关键节点的方法,该方法能同时兼顾节点自身的贡献和节点对其他节点的影响程度,因此十分适用于学术合作网络.     

无标度网络演化过程中的结构熵

熵是度量复杂系统无序性的重要物理量,而且现实中的大多数网络都呈现出无标度网络的特性.在网络的节点熵和结构熵概念的基础上,给出了BA模型的网络结构熵演化的解析结论和数值模拟.从解析结论和数值模拟可以得到,网络结构熵随网络大小以对数的速度增长;但在同样规模下,无标度网络的结构熵小于随机网络的结构熵.     

基于动态网络DEA的区域科技活动效率评价

考虑到科技活动中的动态性及网络性,文章利用基于松弛变量的动态网络DEA模型对中国大陆地区29个省市自治区的科技活动效率进行了测算.研究结果表明,科技生产与科技成果转化存在明显的脱节,且整体效率更多地受到科技生产节点效率的影响.造成东中西部整体效率差异的主要原因在于科技成果转化阶段的效率差异.从科技活动节点看,无论是科技生产节点还是科技成果转化节点,追赶效应均明显大于前沿移动效应.     

节点动态增长对复杂网络传输效率的影响研究

在真实的复杂网络中,网络节点会因为网络拓扑结构的变化而增减,进而导致网络节点间传输效率降低.针对这一问题,通过分析复杂网络节点的动态变化,提出网络节点增加的动态传输模型,并利用真实复杂网络的数据模拟仿真,研究网络节点变化对网络传输效率的影响.结果表明:网络的初始大小会随网络节点的动态增加而变化,其传输效率受节点动态增加的影响在最初阶段表现明显,随着节点的继续增加,网络传输效率会趋于平稳,表现出稳定的网络特性.在这个过程中,复杂网络每次新加入节点的个数和节点边维持了网络信息传输的信息量,强化了网络传的输性能,使得网络具有较好的总体控制能力和有效的节点连接方式.     

基于统计方法的神经网络预测模型研究

与现有网络结构设计方法不同,本文将RBF网络解释为解释变量和被解释变量之间的一个非线性函数,基于RBF网络的学习动态特性提出2种修剪模型WRBF和TRBF。这两种模型根据参数显著性增加和删减节点,为网络结构设计提供了理论依据。对中国信贷序列预测的结果表明,这些模型能够识别外移、萎缩和衰减等冗余核函数,得到的精简网络具有最好的预测精度,对于提高货币政策前瞻性具有很好应用价值。     

链式网络DEA模型

数据包络分析(DEA)是评价决策单元(DMU)相对有效性的一种工具,现已得到广泛的应用.传统的DEA不考虑系统内部结构,而是将系统作为一个"黑箱"来度量效率.针对多阶段网络结构提出一个新的网络DEA模型—链式网络DEA模型.研究网络决策单元的网络DEA有效性及各个阶段的弱DEA有效性之间的关系,给出了网络DEA有效的充分必要条件.若网络决策单元不是网络DEA有效的,根据模型可以指出系统在哪些阶段是无效的.     

弧k/n(G)与节点k/n(G)网络模型可靠性估计的对偶变量蒙特罗洛方法

针对弧k/n(G)网络无法刻画网络节点对上游节点输入需求的问题,提出了节点k/n(G)网络模型.在节点k/n(G)网络中,通过设定网络节点工作条件为接收工作输入点集中n个节点里的至少k个输入,节点k/n(G)性质被进一步延伸至对上游任意节点.为采用蒙特卡洛方法对弧与节点k/n(G)网络的可靠性进行估计,分别对两类k/n(G)网络设计了基于随机邻接矩阵的网络连通性算法.并结合k/n(G)网络结构函数的单调性,将对偶变量方差缩减技术应用于两类k/n(G)网络的蒙特卡洛方法,仿真实验表明:所设计的仿真方案能够有效地对两类k/n(G)网络的可靠性进行估计,对偶变量方法提高了蒙特卡洛方法的计算精度并减少了计算时间.     

具有偏好锥的链式网络DEA模型

对链式网络DEA模型进行推广,将"偏好锥"引入网络DEA模型.针对中间产出重要性以及决策者评价时的偏好,建立带有产出锥和投入锥相应的两阶段生产可能集,对具有"偏好锥"的链式网络DEA模型,证明了决策单元为网络DEA有效的充要条件,给出了网络DEA有效性与各阶段弱DEA有效性的关系.另外,文章结合具体算例说明了偏好锥的变化对效率评价的影响.关于两阶段的模型以及相关结论可以推广到多阶段网络结构.     

科技成果转化团队知识网络中知识共享的博弈模型

构建了科技成果转化团队知识网络中知识共享的演化博弈模型,分析了核心节点的收益分配策略和普通节点的知识共享策略选择决策,得到了模型的均衡解、复制动态和稳定性,讨论了知识共享的影响因素,并进行了数值实验.研究结果表明:1)核心节点选择"高收益分配策略"、普通节点选择"知识共享策略"的概率是一个震荡性螺旋提升过程;2)影响普通节点知识共享的正向因素有"普通节点用于知识共享的资金投入量"等;3)影响核心节点收益分配策略选择的正向因素有"普通节点出入度期望值"等.     

Mathematical Models for Studying the Value of Cooperational Leadership in Team Replacement

Mathematical models are presented for studying the value of leadership in a team whose composition is changing over time. The models are based on a leader's role of achieving cooperation among the interacting members so that they perform their tasks better and hence improve overall team performance. Three different approaches, modified from Kauffman's NK model, are proposed. Each model includes controllable parameters whose values reflect the amount of interaction among the workers as well as the skill and variance of the leader in achieving cooperation. Computer simulations are used to show how the skill level and variance of the leader affect the expected performance of the team. Managerial insights into the value of the leader—such as the fact that finding a more skillful leader can be more important to team performance than controlling the amount of interaction among the team members—are provided.     

生命线网络系统多节点失效的应急抢修队伍派遣模型研究

针对生命线网络系统中多个节点失效的应急抢修问题,给出了抢修队伍派遣优化模型以及模型的求解方法。在本文中,首先考虑应急修复所需时间、各节点失效所造成的损失和应急修复所需成本等因素,构建了以节点失效损失最小和应急修复成本最低为目标的抢修队伍派遣优化模型;然后针对优化模型的特点,给出了模型的求解方法。最后,通过一个算例分析说明了构建的模型的可行性和有效性。     

团队规范下管制员违章行为演化与监管研究

为发现团队规范下管制员违章行为及监管策略的演化博弈规律,运用演化博弈理论,构建安全管理者与管制员演化博弈模型,分析博弈系统均衡点的局部稳定性。在此基础上建立演化博弈的系统动力学模型,仿真模拟不同情形下博弈双方策略选择的动态演化过程,并分析模型参数变化对系统演化结果的影响。结果表明:正的团队规范有助于系统演化至理想模式,负的团队规范会使系统陷入“不良锁定”模式和“震荡”模式;管制员行为收益、行为成本、被监查到的概率、处罚力度、监管成本等因素均对系统演化结果产生影响。鼓励班组成员对违章行为进行否定性评价、加大对管制员的处罚力度等均能够长效促进管制员主动遵章。     

单元生产下劳动分工与团队生产的组合策略

单元生产是多品种小批量模式下能柔性适应的方式之一,在U型设备布置下存在操作工技能多样化要求与团队协作导致整体效率下降的两种困境.运用概率论的工具分析劳动分工与"搭便车"对单元生产的团队技能的影响,建立分层的目标管理模式与重新组建的岗位配置方式,实施委托代理的监督机制,根据测评系统下团队成员的绩效行为在薪酬上的体现差异化,提高单元生产团队的劳动效率.     

基于可拓方法的虚拟项目团队构架

虚拟项目团队是网络经济条件下产生的一种新的团队组织形式,目前,许多知识型项目团队的构架均采用这种方式.利用可拓工程方法完成了虚拟项目团队从任务确定、职责分工、人员甄选,直到项目团队构架的整个过程.方法的运用,为虚拟项目团队的进一步研究提供了一种新的思维方式和研究方法.     

How to get the timing right. A computational model of the effects of the timing of contacts on team cohesion in demographically diverse teams

Lau and Murnighan’s faultline theory explains negative effects of demographic diversity on team performance as consequence of strong demographic faultlines. If demographic differences between group members are correlated across various dimensions, the team is likely to show a “subgroup split” that inhibits communication and effective collaboration between team members. Our paper proposes a rigorous formal and computational reconstruction of the theory. Our model integrates four elementary mechanisms of social interaction, homophily, heterophobia, social influence and rejection into a computational representation of the dynamics of both opinions and social relations in the team. Computational experiments demonstrate that the central claims of faultline theory are consistent with the model. We show furthermore that the model highlights a new structural condition that may give managers a handle to temper the negative effects of strong demographic faultlines. We call this condition the timing of contacts. Computational analyses reveal that negative effects of strong faultlines critically depend on who is when brought in contact with whom in the process of social interactions in the team. More specifically, we demonstrate that faultlines have hardly negative effects when teams are initially split into demographically homogeneous subteams that are merged only when a local consensus has developed.     

基于成果转化贡献的科研团队成员收益分配研究

促进科技成果转化是我国深化科技体制改革的重要内容,是科技成果转化为现实生产力的关键环节,是实施创新驱动发展战略的根本要求。科研团队成员作为企业科技创新活动的主体,让其参与成果转化收益的分配,有利于调动其科技创新与成果转化的积极性。本文通过理论分析,采用主成分分析法和关键绩效指标法,研究科研团队成员在成果转化阶段的贡献的关键指标、权重及量表,构建收益分配模型。研究结论为完善科技成果转化各利益相关者的激励机制提供了理论依据。     

Virtual Teams: What are their Characteristics, and Impact on Team Performance?

To date, efforts to understand virtual teaming have been largely anecdotal and atheoretical. Therefore, drawing from the extant research in the groups domain, we attempt to ground the definition of a virtual team in well-established group-level constructs, and design a simulation study to investigate the impact of different virtual team characteristics on team performance. Essentially, we argue that the virtual team is defined by three key characteristics—the virtual team context, the virtual team composition, and the virtual team structure. Using the VDT computational discrete event simulation model as our experimental platform, we simulated different virtual team models, and examined their impact on various team performance dimensions. We found that virtual team characteristics have different effects on different aspects of team performance. The virtual context team had a lower rework volume but higher coordination volume and longer project duration than the virtual composition team. Interestingly, we also found that the virtual structure team performed better than the software development team baseline model in all aspects of team performance. Based on these results, we proposed strategies to improve performance in different types of virtual team. Specifically, we propose (1) increasing the ease of communication and availability of routines in the virtual context team; (2) clarifying role expectations and fostering a team culture in the virtual composition team; and (3) implementing a lateral structure in the virtual team. Our results also suggest that firms should consider situational demands, specifically tolerance for errors and coordination volume, when considering the design of virtual teams.     

关于科研事业单位知识型团队绩效评价的实证分析——基于胜任力模型

我国科研事业单位普遍面临绩效考核困境,不能满足知识经济背景下知识型团队的管理要求。胜任力模型可以有效地对知识型团队成员进行选拔、配置与管理,是团队取得高绩效的关键。本研究采用问卷调查结合行为事件访谈的方法,筛选科研事业单位知识型团队的胜任力特征,并采用主成分分析方法,从7个维度构建了知识型团队胜任力模型。在此基础上,采用层次分析法,对团队业绩、胜任力、行为指标进行两两比较,确认其相对重要性,进一步构建了绩效评价体系。结果发现,在科研事业单位知识型团队中,成员个人能力的提升、团队信息共享和效率以及团队管理者的能力是最重要的团队胜任力特征,而外部支持和人际关系相对次要。胜任力指标在绩效评价体系中占有重要的地位。而团队行为对团队绩效的影响也不可忽视。     

How attitude certainty tempers the effects of faultlines in demographically diverse teams

Lau and Murnighan’s faultline theory suggests that strong demographic faultlines can undermine cohesion in work teams. A strong faultline splits a team into internally homogeneous but mutually dissimilar subgroups based on demographic characteristics. Social influence processes within these subgroups then lead to the polarization of team members’ attitudes along the divisions imposed by the faultline. However, faultline theory hitherto neglects effects of attitude certainty. Research shows that the certainty with which individuals hold their attitudes affects social influence processes. We extend theoretical faultline research by integrating attitude certainty. For this, we incorporate the interplay of the dynamics of attitude certainty and social influence into a formal model of demographic faultline effects developed by Flache and Mäs. Computational experiments suggest a moderation effect. Demographic faultlines only affect team cohesion if attitude certainty is low. We discuss implications for future research.