A Semiparametric Regression Model for Longitudinal Data with Non‐stationary Errors

Motivated by the need to analyze the National Longitudinal Surveys data, we propose a new semiparametric longitudinal mean‐covariance model in which the effects on dependent variable of some explanatory variables are linear and others are non‐linear, while the within‐subject correlations are modelled by a non‐stationary autoregressive error structure. We develop an estimation machinery based on least squares technique by approximating non‐parametric functions via B‐spline expansions and establish the asymptotic normality of parametric estimators as well as the rate of convergence for the non‐parametric estimators. We further advocate a new model selection strategy in the varying‐coefficient model framework, for distinguishing whether a component is significant and subsequently whether it is linear or non‐linear. Besides, the proposed method can also be employed for identifying the true order of lagged terms consistently. Monte Carlo studies are conducted to examine the finite sample performance of our approach, and an application of real data is also illustrated.     

Farmers' Contribution to Agricultural Social Capital: Evidence from Southern Spain

Social capital is the whole set of shared norms, values, attitudes, and beliefs that promote cooperation among individuals within the community and that has proved to be a key factor in explaining development processes. This article aims to provide an analytically reliable notion of social capital within the farming sector and a methodological tool for empirically measuring how social capital is accumulated at the farmer level. The theoretical framework proposed is based on the multidimensionality of the complex concept of social capital. Thus, to develop a comprehensive index for social capital, we identify three dimensions of the concept, structural, relational, and cognitive social capital, each one also comprising several subdimensions. This integrative approach permits creation of a composite indicator of the agricultural social capital accumulated at the farmer level, further identifying socioeconomic factors that influence its accumulation at that level. We empirically apply this methodological approach to farmers in Andalusia in southern Spain as a case study. This research provides an interesting starting point for informing policymakers about social capital and helping them implement the necessary programs to facilitate sustainable development in the agricultural sector.     

Caloric restriction minimizes aging effects on the femoral medial condyle

This study aimed to analyze the effects of caloric restriction on aged femoral articular cartilage of Wistar rats. Three groups of eight animals each were considered: young (YC) and old (OC) control groups fed with a normal diet and old caloric restriction group (OCR) composed of 18-month-old animals fed with a 31% less caloric diet from 6-months of age. Articular cartilage was studied through morphometry and immunohistochemistry. Body mass was 12% less in the OCR group than in the OC group. The articular cartilage from OC rats show thinner medial condyles, fewer chondrocytes, smaller chondrocytes nuclear volume and, in both condyles, a predominance of collagen type II and less collagen density compared to both YC and OCR groups (p?p?相似文献   

奥巴马政府对朝政策的新理念及其走向

奥巴马政府上台后,其主要致力于应对金融危机和反恐战争.对朝政策上,其在"巧实力"外交理念的指导下,寻求在外交、经济、军事、政治、法律和文化等所有政策工具中选择正确的工具或组合.针对朝核问题的敏感性和脆弱性,奥巴马政府倾向于"冷处理",继而"多管齐下",在合作外交的框架内展开更加灵活的外交活动,促使朝鲜重返六方会谈,继续以对话方式处理相关问题,不过美国也适度增强了对朝鲜的威慑力量,奥巴马政府仍对美朝关系正常化持一种谨慎态度.     

企业核心人才流出问题浅析

企业核心人才的流出不仅对员工个人、企业 ,而且对社会 ,也会产生一定的影响。因此 ,要解决此问题 ,企业首先要树立良好的企业形象 ;其次要做好服务和引导工作 ,为他们提供一个良好的工作环境 ,而非采取一些逼迫性的强制措施     

Graphical and Numerical Methods for Detecting Influential Observations in Complex Bingham Data

We describe methods to detect influential observations in a sample of pre-shapes when the underlying distribution is assumed to be complex Bingham. One of these methods is based on Cook's distance, which is derived from the likelihood of the complex Bingham distribution. Other method is related to the tangent space, which is based on the local influence for the multivariate normal distribution. A method to detect outliers is also explained. The application of the methods is illustrated in both a real dataset and a simulated sample.     

贵州苗族鼓藏节仪式的人类学考察——以贵州黔东南苗族侗族自治州榕江县计怀乡乌略村为例

通过田野调查对乌略苗族村鼓藏节仪式过程进行了具体的描述,分析了鼓藏节仪式的社会权利功能、社会认同功能、社群联系与娱乐功能、经济功能等基本社会功能,指出苗族鼓藏节仪式由于现代性的切入所发生的功能意义上的嬗变是文化变迁的一种必然结果.     

秦、西汉的“内臣”与“外臣”

本文对文献记载中西汉政权处理民族关系时出现的“内臣”和“外臣”作了分析 ,归纳了它们在与中央政权关系上各自不同的特点。作者在分析云梦睡虎地秦简的基础上认为 ,秦简中的“臣邦”相当于汉代“内臣” ,“外臣邦”相当于汉代“外臣” ;并指出文献中的“羁縻”制度等同于“外臣” ,“葆塞蛮夷”相当于“内臣” ;同时提出“内诸侯”和“外诸侯”的称呼不适合于汉代分封和民族政策 ,应以汉代习称的“内臣”和“外臣”为准。最后 ,本文归纳了“外臣”向“内臣”转化的途径和原因 ,提出中央政权军事力量的壮大是完成此转化的直接动力。     

西双版纳傣族宗教生活的世俗化倾向--以嘎洒、勐罕、大勐龙三镇为例

如果对20世纪90年代以来西双版纳傣族的宗教生活做一个总体的回顾,就可以得出这样的结论西双版纳傣族的小乘佛教正处于日益世俗化的进程中.文章以西双版纳三个傣族乡镇的宗教生活为田野调查个案,并对这三个个案进行了比较分析,从中得出西双版纳傣族的宗教生活在不同方面、不同程度上都存在着世俗化的倾向.本文以此为切入点,来探讨社会转型时期西双版纳傣族的文化价值取向.