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.     

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     

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.     

建设环境友好型社会的伦理思考

人作为一种关系中的存在,对于环境的独立性始终不能摆脱其对环境的依赖性,当人认识到这种必然性时,人与环境的伦理关系就产生了.作为环境干预主体的政府、企业和普通民众在这种自我约束、自我管理的伦理建构中应该明确各自应有之责任和发挥各自应有之作用,从而共同构建环境友好型社会.     

对撒拉族女童教育状况的人类学调查与研究

撒拉族青少年的教育状况,尤其女童教育状况自20世纪80年代初以来一直不容乐观,备受关注。本文从教育人类学的角度,参考先前学者的调查结果,结合当地实际,对新世纪撒拉族女童的教育状况进行了调查与分析。在分析了影响撒拉族女童教育的主、客观两个方面的原因后,作者提出少数民族女童的教育状况,不能仅仅凭借学校教育为本来做结论,与家庭教育有关的少数民族"本土文化"教育也不容忽视。     

Sourcing with Deferred Payment and Inspection under Supplier Product Adulteration Risk

We study the deferred payment and inspection mechanisms for mitigating supplier product adulteration, with endogenous procurement decision and general defect discovery process. We first derive the optimal deferred payment contract, which reveals that either entire or partial deferral can arise, depending on the moral hazard severity and the information accumulation rate. Because of the supplier's incentive to adulterate, the optimal procurement quantity under deferred payment generally is smaller than the first‐best quantity. We then investigate the inspection mechanism and characterize the equilibrium. We find that under the inspection mechanism, the optimal procurement quantity is no less than the first best. A comparison between these two mechanisms shows that the deferred payment mechanism generally can outperform the inspection mechanism when either the market size is small or the profit margin is low. However, we find that these two mechanisms can also be complementary, for which we characterize a necessary condition.     

Customer Use of Virtual Channels in Multichannel Services: Does Type of Activity Matter?

Many firms have recently adopted virtual channels, based most notably on the Internet and the phone, to complement the delivery of services to their customers by their existing physical facilities. The success of such multichannel (MC) strategies relies on the alignment of service design decisions—namely those concerning the allocation of service activities to virtual channels—with customers’ MC behavior. Although prior studies have looked at the intensity with which customers use virtual channels, they have not addressed virtual channel use for different types of service activities. In our study, we investigate whether customers’ use of virtual channels for MC services varies with the type of service activities they engage in, and if so, in what way. In doing so, we address two objectives. First, we investigate the impact of accessibility to the physical channel on the degree of use of virtual channels (Internet and phone, aggregated) for different types of activities. Second, we look at channel preferences (Internet vs. phone) for different types of activities when customers do resort to virtual channels to conduct activities. To address our objectives, we develop and test hypotheses regarding customers’ use of virtual channels based on the match between activity attributes (complexity and volume) and channel attributes (access efficiency, interface efficiency, interface richness). Using data from a MC bank, we find that the impact of accessibility to physical channels (specifically, customer distance) on customers’ use of virtual channels, as well as the relative use of Internet versus phone, depend on the type of activities.