Reviews

Abstract

Elizabeth Parang reviews Reengineering the Library: Issues in Electronic Resources Management. Scott Johnson reviews Academic Library Management: Case Studies.     

Time-varying clustering of multivariate longitudinal observations

Abstract

We propose a statistical method for clustering multivariate longitudinal data into homogeneous groups. This method relies on a time-varying extension of the classical K-means algorithm, where a multivariate vector autoregressive model is additionally assumed for modeling the evolution of clusters' centroids over time. Model inference is based on a least-squares method and on a coordinate descent algorithm. To illustrate our work, we consider a longitudinal dataset on human development. Three variables are modeled, namely life expectancy, education and gross domestic product.     

Adaptive Gaussian Markov random fields with applications in human brain mapping

Summary.  Functional magnetic resonance imaging has become a standard technology in human brain mapping. Analyses of the massive spatiotemporal functional magnetic resonance imaging data sets often focus on parametric or non-parametric modelling of the temporal component, whereas spatial smoothing is based on Gaussian kernels or random fields. A weakness of Gaussian spatial smoothing is underestimation of activation peaks or blurring of high curvature transitions between activated and non-activated regions of the brain. To improve spatial adaptivity, we introduce a class of inhomogeneous Markov random fields with stochastic interaction weights in a space-varying coefficient model. For given weights, the random field is conditionally Gaussian, but marginally it is non-Gaussian. Fully Bayesian inference, including estimation of weights and variance parameters, can be carried out through efficient Markov chain Monte Carlo simulation. Although motivated by the analysis of functional magnetic resonance imaging data, the methodological development is general and can also be used for spatial smoothing and regression analysis of areal data on irregular lattices. An application to stylized artificial data and to real functional magnetic resonance imaging data from a visual stimulation experiment demonstrates the performance of our approach in comparison with Gaussian and robustified non-Gaussian Markov random-field models.     

Bayesian analysis of human movement curves

Summary.  We consider the Bayesian analysis of human movement data, where the subjects perform various reaching tasks. A set of markers is placed on each subject and a system of cameras records the three-dimensional Cartesian co-ordinates of the markers during the reaching movement. It is of interest to describe the mean and variability of the curves that are traced by the markers during one reaching movement, and to identify any differences due to covariates. We propose a methodology based on a hierarchical Bayesian model for the curves. An important part of the method is to obtain identifiable features of the movement so that different curves can be compared after temporal warping. We consider four landmarks and a set of equally spaced pseudolandmarks are located in between. We demonstrate that the algorithm works well in locating the landmarks, and shape analysis techniques are used to describe the posterior distribution of the mean curve. A feature of this type of data is that some parts of the movement data may be missing—the Bayesian methodology is easily adapted to cope with this situation.     

四川盆地西北部蕈菌资源

1986年以来在四川盆地西北部采集到205种草菌,其中包括省内新记录种60种,国内新记录种4种。根据G.C.Ainsworth等(1973)的分类系统分类并命名。所有标本保藏在四川锦阳农业专科学校真菌标本室。     

组织信息资源管理论纲

本文在简要分析现代组织管理环境基本特点的基础上,对社会组织的信息资源管理的功能、原则及其运作等若干问题进行了认真的探讨,以期进一步完善现代组织管理理论。     

以改善人际关系促进大学生心理健康发展

和谐人际关系是大学生心理健康的重要评判标准,心理健康问题突出表现在人际关系方面,亲密人际关系的丧失极易导致身心疾病甚至死亡。应针对大学生人际交往特点培养其交往品质、养成交际技能,引导大学生主动、积极交往,以促进大学生心理健康水平的提高。     

网络环境下图书馆采访工作初探

分析了网络环境给图书馆工作所带来的机遇和优势 ,认为它不仅使图书馆的采购方式得到了优化 ,而且也大大提高了购书质量和采购效率 ,节约了大量资金。据此 ,提出面对新的形势发展 ,应该通过强调提高采访人员素质、实现资源共享、建立文献出版信息数据库及相关信息库、合理选择各类信息资源等措施来进一步加强图书馆的采访工作 ,以便真正提升建立高质量馆藏所产生的实际应用价值。     

我国东西部卫生人力资源对比分析

将我国东、中、西三个区域的经济发展状况与其卫生发展状况进行比较分析,结果显示,不同区域的卫生人力资源分配存在着很大的差别:东部最优,西部最差。研究中结合我国现行卫生体制,提出与我国西部大开发相适应的西部卫生发展战略及补偿方案。     

论贵州乡村旅游的发展

进入21世纪以来,乡村旅游已经成为我国旅游业的重要组成部分。乡村旅游是贵州旅游产品建设的重要内容,是加强贵州旅游核心竞争力的重要手段,是贵州旅游业结构调整的重要方面。在乡村旅游业的发展过程中,要协调好乡村旅游与各种利益群体间的关系,在乡村旅游中要注意突出个性特色,发掘文化资源,加强政府作用。