Marginal Regression of Gaps Between Recurrent Events

Recurrent event data typically exhibit the phenomenon of intra-individual correlation, owing to not only observed covariates but also random effects. In many applications, the population may be reasonably postulated as a heterogeneous mixture of individual renewal processes, and the inference of interest is the effect of individual-level covariates. In this article, we suggest and investigate a marginal proportional hazards model for gaps between recurrent events. A connection is established between observed gap times and clustered survival data with informative cluster size. We subsequently construct a novel and general inference procedure for the latter, based on a functional formulation of standard Cox regression. Large-sample theory is established for the proposed estimators. Numerical studies demonstrate that the procedure performs well with practical sample sizes. Application to the well-known bladder tumor data is given as an illustration.     

基于产业集群的技术创新扩散研究

对产业集群内技术创新扩散特征进行了分析,揭示了产业集群促进技术创新扩散的本质;同时对产业集群内技术创新扩散的动态过程进行研究,分析参数变化对技术创新扩散的影响,为企业正确认识产业集群内技术创新扩散规律并采取相应措施提供了理论依据.     

Assessing the impact of new technology in information systems

Computer and communication technology is changing at an increasing rate. New technologies are emerging: the price- performance of current technology is improving. There is a need to assess the impact of technology on new information systems projects, particularly those dealing with distributed processing and electronic office systems. Such an assessment provides direction and guidance in long range and intermediate term information services planning. It can potentially prevent costly conversion efforts. An approach is developed for obtaining this assessment. Two case examples of applications are provided which illustrated the method, results and benefits.     

福建粮食生产需要有新的思路和对策

阐明了福建粮食生产的主要思路 ,即从单纯的计划经济转型到宏观调控与市场导向相结合的轨道上来。讨论了与其相关的评估形势、对付风险、调整结构和增加自主等问题 ,提出完善购销政策、调整种植结构、更新优质品种和增强科技力度等对策和建议     

The Relation between Parental Constructive Behavior and Adolescent Association with Achievement-Oriented Peers: A Longitudinal Study

There is abundant research about the negative influences of peer groups and other factors contributing to adolescent involvement with deviant peers. This study used three waves of panel data to investigate the relation between parental constructive behavior and adolescent association with achievement-oriented peers. Parental constructive behavior was found to be positively related to adolescents'own achievement orientation a year later, which in turn was positively related to the perceived achievement orientation of friends two years later. However, adolescents'own achievement orientation did not completely mediate the effect of parental constructive behavior on the perceived achievement orientation of friends. Furthermore, after the prior perceived achievement orientation of friends was added into the model, parental constructive behavior still had a direct effect on the perceived achievement orientation of friends over time. Parental constructive behavior contributed to the affiliation with achievement-oriented friends above and beyond the effects of adolescents'own achievement orientation and their prior peer affiliation.     

谈白居易的"中隐"

唐代大诗人白居易的思想中明显地杂糅着儒、释、道色彩 ,因而也就构成了积极用世与消极退隐的矛盾性。腐朽黑暗的封建统治等因由 ,令其欲进不能 ,欲退不忍 ,后期终于选择了“中隐”之路。这条路使他免除苦厄 ,保全自我 ,同时也拓展了创作领域。     

试述图表资料在生物教学中的作用

图表资料具有直观性、系统性及概括性的特点,在生物教学中有着重要地位及作用．     

市场经济条件下企业筹资初步分析

论述了市场经济条件下资金供应和企业筹资的要求和条件,并通过对企业筹资的分析,选择出经济合理的筹资渠道及方式,实现企业最佳资金筹集和运用。     

同态滤波在扭矩载荷识别中的应用

通过理论分析和实验验证,证明了采用同态滤波的方法识别机器扭矩载荷的可行性。同时提出了根据时序模型的Ｇｒｅｅｎ函数来判定窗函数宽度的方法,减少了选取窗函数宽度的盲目性。作为应用实例,给出了采煤机扭矩的识别结果。