三维异质性视角下的董事会结构对企业创新的影响——基于中国制造业上市公司的实证研究

董事会的人员结构特征对企业创新战略及关键决策具有重要影响,异质性是衡量董事会人员结构特征的重要指标。文章利用中国制造业上市公司的经验数据,实证检验了董事会成员结构三个关键维度即人口统计结构、知识结构和地缘文化结构的异质性特征对企业创新的影响。结果发现,董事会结构的三维异质性均与企业创新产出呈现倒“U”型关系,这意味着董事会人员结构异质性对企业创新产出存在某个“最佳”点或区间。文章的研究结果对于基于企业高层团队结构的创新理论发展与管理实践,均具有较好的指导价值。     

考虑异质性行为的灾后应急物资动态调度优化

在以人道主义为本的应急救援活动中,不可忽视被救灾民和施救决策者们异质性行为的影响。一方面,将各灾民因救援物资需求未被及时满足而呈现的差异化心理痛苦度量成经济损失,并纳入应急救援调度的社会成本这一决策目标中;另一方面,在灾后物资调度决策中,关注具有异质性偏好的各应急决策者所展现出的不同救援态度。结合面向联合机会约束规划的动态供需平衡限制,最终构建一个考虑灾民和决策者们异质性行为的多阶段灾后救援物资分配和应急路径优化模型。采用2008年汶川地震为案例背景,应用遗传算法对模型求解和参数分析,将仿真结果与不考虑异质性行为的传统救援调度方案进行比较,得出一些结论为构建高效的应急救援体系提供有益参考。     

高管海外背景与企业社会责任

基于社会资本理论和资源基础观,探讨高管团队背景特征（职能背景、特殊工作经历）对企业自主创新的作用机制,并从高管团队行为视角明晰了联盟网络的数量特征、伙伴特征在其中的中介作用。运用新兴战略行业沪深两市主板上市企业的专利数据,实证检验所提出的理论框架。结果发现,高管团队职能背景对企业自主创新具有显著的正相关关系,且不同的职能背景（“产出型”“生产型”和“支持型”）对企业创新的正向影响程度具有差异性;而企业的联盟网络数量特征、伙伴特征与企业的自主创新存在倒U型关系,且两者在高管团队（职能背景和特殊工作经历）与企业自主创新之间发挥着部分中介作用。     

人力资本梯度升级的经济增长效应

人力资本梯度升级是指人力资本由低至高逐步跃迁的高级化过程,其可能通过促进产业结构升级、技术创新作用于经济增长。利用2000—2015年全国30个省级行政区面板数据,实证分析了人力资本梯度升级的经济增长效应。研究发现:人力资本梯度升级对经济增长有显著的促进效应,第三梯度人力资本对经济增长促进效应最强。人力资本梯度升级的经济增长效应存在时间和地区异质性:随时间的推进,人力资本梯度升级对经济增长的促进效应逐渐增强;东部和高经济发展地区人力资本梯度升级的经济增长效应要高于西部和低经济发展地区。基于以上结论,为推动经济长期增长进一步提出可行的对策建议。     

LOG-LINEAR MODELS FOR MEAN AND DISPERSION IN MIXED POISSON REGRESSION MODELS

This paper is concerned with the analysis of repeated measures count data overdispersed relative to a Poisson distribution, with the overdispersion possibly heterogeneous. To accommodate the overdispersion, the Poisson random variable is compounded with a gamma random variable, and both the mean of the Poisson and the variance of the gamma are modelled using log linear models. Maximum likelihood estimates (MLE) are then obtained. The paper also gives extended quasi-likelihood estimates for a more general class of compounding distributions which are shown to be approximations to the MLEs obtained for the gamma case. The theory is illustrated by modelling the determination of asbestos fibre intensity on membrane filters mounted on microscope slides.     

社会语言学的语言观和方法论

语言是一个异质有序的结构系统,尽管存在着错综复杂的变异形式,但它们却沿着一定的方向发展变化。社会语言学有关语言变异的描写和解释方法论,不仅能够有效地解释语言变化的起因,而且可以描述语言变化的过程,在某种情况下,还可以预测语言变化的趋势。     

Extending the Stochastic Two-Stage Model of Carcinogenesis to Include Self-Regulation of the Nonmalignant Cell Population

One of the challenges of introducing greater biological realism into stochastic models of cancer induction is to find a way to represent the homeostatic control of the normal cell population over its own size without complicating the analysis too much to obtain useful results. Current two-stage models of carcinogenesis typically ignore homeostatic control. Instead, a deterministic growth path is specified for the population of "normal" cells, while the population of "initiated" cells is assumed to grow randomly according to a birth-death process with random immigrations from the normal population. This paper introduces a simple model of homeostatically controlled cell division for mature tissues, in which the size of the nonmalignant population remains essentially constant over time. Growth of the nonmalignant cell population (normal and initiated cells) is restricted by allowing cells to divide only to fill the "openings" left by cells that die or differentiate, thus maintaining the constant size of the nonmalignant cell population. The fundamental technical insight from this model is that random walks, rather than birth-and-death processes, are the appropriate stochastic processes for describing the kinetics of the initiated cell population. Qualitative and analytic results are presented, drawn from the mathematical theories of random walks and diffusion processes, that describe the probability of spontaneous extinction and the size distribution of surviving initiated populations when the death/differentiation rates of normal and initiated cells are known. The constraint that the nonmalignant population size must remain approximately constant leads to much simpler analytic formulas and approximations, flowing directly from random walk theory, than in previous birth-death models.(ABSTRACT TRUNCATED AT 250 WORDS)     

大学知识溢出与科技经费配置：“顶天”与“立地”的权衡

大学作为知识的生产者和传播者,对企业有知识溢出效应,能促进企业创新并带动区域经济发展。通过一个简洁的量化空间经济学模型,从微观层面实证检验中国大学对工业企业创新的知识溢出效应,发现大学的知识溢出效应具有很强的异质性：高水平的研究型大学具有更强的知识溢出能力,高技术行业与大企业从大学的知识溢出中受益更多。反事实研究表明,保持中国现有大学的空间布局不变,更为均衡的科技经费配置能改善大学对企业的知识溢出效应,最多可带来社会总福利1.3个百分点的提升。