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1.
In this paper, we consider the deterministic trend model where the error process is allowed to be weakly or strongly correlated and subject to non‐stationary volatility. Extant estimators of the trend coefficient are analysed. We find that under heteroskedasticity, the Cochrane–Orcutt‐type estimator (with some initial condition) could be less efficient than Ordinary Least Squares (OLS) when the process is highly persistent, whereas it is asymptotically equivalent to OLS when the process is less persistent. An efficient non‐parametrically weighted Cochrane–Orcutt‐type estimator is then proposed. The efficiency is uniform over weak or strong serial correlation and non‐stationary volatility of unknown form. The feasible estimator relies on non‐parametric estimation of the volatility function, and the asymptotic theory is provided. We use the data‐dependent smoothing bandwidth that can automatically adjust for the strength of non‐stationarity in volatilities. The implementation does not require pretesting persistence of the process or specification of non‐stationary volatility. Finite‐sample evaluation via simulations and an empirical application demonstrates the good performance of proposed estimators.  相似文献   
2.
This article considers statistical inference for the heteroscedastic partially linear varying coefficient models. We construct an efficient estimator for the parametric component by applying the weighted profile least-squares approach, and show that it is semiparametrically efficient in the sense that the inverse of the asymptotic variance of the estimator reaches the semiparametric efficiency bound. Simulation studies are conducted to illustrate the performance of the proposed method.  相似文献   
3.
I call for a globally informed sociology of comparative placemaking that integrates historical and contemporary processes and includes the ephemeral, institutional, and personal. By placemaking, I am referring to the explicit or tacit cooperation among people to create, maintain, and give meaning to places in space through bodily occupation given differential resources and constraints. I review select place, space, and community-based literature about urban, Black, migrant, LGBTQ, and international populations to think about how we can build upon and integrate multiple theoretical, methodological, and epistemological insights to form an explicit placemaking research agenda. A US focus on neighborhoods contrasts with a comparative examination of global urban networks, social polarization, and transformation of the built environment in the interdisciplinary field of global urban studies (Ren, 2018). I argue for a placemaking research agenda that bridges insight from US Urban Sociology with Global Urban Studies to consider how various structures and actors constrain and facilitate place projects. With a globally reaching and comparatively informed sociology of placemaking, we can illuminate our multi-structured story of place and agency in context. We can answer questions about how and why we co-create and are simultaneously disciplined by the process of creation.  相似文献   
4.
张弘  王小红 《民族学刊》2021,12(10):59-64, 123
丹巴位于“藏彝走廊”的核心区域,其对汉藏民族关系、中央政权与边疆地区的稳定均具有重要影响。自忽必烈时期开始丹巴即开始实行土司制度直至新中国成立,研究丹巴的土司制度发展历史对梳理“藏彝走廊”民族关系及社会发展历史具有重要作用。本文对丹巴土司制度的发展历史进行了考证,并对其境内的四个土司的管辖范围、权力地位进行了梳理,以期对该地区历史发展研究提供一些参考与借鉴。  相似文献   
5.
ABSTRACT

By using the probabilistic framework of production efficiency, the paper develops time-dependent conditional efficiency estimators performing a non-parametric frontier analysis. Specifically, by applying both full and quantile (robust) time-dependent conditional estimators, it models the dynamic effect of health expenditure on countries’ technological change and technological catch-up levels. The results from the application reveal that the effect of per capita health expenditure on countries’ technological change and technological catch-up is nonlinear and is subject to countries’ specific income levels.  相似文献   
6.
As important members of research teams, statisticians bear an ethical responsibility to analyze, interpret, and report data honestly and objectively. One way of reinforcing ethical responsibilities is through required courses covering a variety of ethics-related topics at the graduate level. We assessed ethics requirements for graduate-level statistics training programs in the United States for the 2013–2014 academic year using the websites of 88 universities, examining 103 biostatistics programs, and 136 statistics degree programs. We categorized programs’ ethics training requirements as required or not required. Thirty-one (35.1%) universities required an ethics course for at least some degree students. Sixty-two (25.5%) degree programs required an ethics course for at least some students. The majority (77.4%) of required courses were worth 0 or 1 credit. Of the 177 programs without an ethics requirement, 19 (10.7%) listed an ethics elective. Although a single ethics course is insufficient for instilling an ethical approach to science, degree programs that model expectations through coursework point to the value of ethics in science. More training programs should prepare statisticians to consider the ethical dimensions of their work through required coursework. Supplementary materials for this article are available online.  相似文献   
7.
Previous research reveals that the temporal ordering of childbearing and marriage can have an impact on the meaning of first-time marriage. This article aims to obtain a deeper understanding of meaning-making of first-time marriage in relation to childbearing. Narrative interviews with 16 brides and grooms in 8 couples in Sweden were conducted. The material was analyzed in relation to the temporal ordering of childbearing and marriage. The study reveals that the construction of meaning of marriage does not only relate to the temporal context. Social factors such as social class or family formation might also be relevant for how meaning is constructed. This article contributes to a deeper understanding of meaning-making as a relational process constructed within particular contexts.  相似文献   
8.
福建省科技资源配置的现状、问题及对策   总被引:7,自引:3,他引:4  
利用翔实的统计数据和资料,从科技人力资源、财力资源、技术资源等方面分析了福建省科技资源配置的现状及存在的问题,并针对存在的问题提出了相应的对策和建议。  相似文献   
9.
无意识是一种不为意识所知的特殊心理活动,在科学创造中起着非常重要的作用.本文试就无意识心理活动与科学创造的关系问题加以探讨,重点分析无意识的深隐性、可解性、偶现性的内在和谐以及三者之间的和谐互动在科学创造中的作用.  相似文献   
10.
初探高校教学与科研的良性循环   总被引:1,自引:0,他引:1  
正确认识和处理好教学与科研相互依存和相互矛盾的关系及制约这一关系的诸多因素 ,才能实现高校的人才培养和科研成果双丰收 ,促进教学与科研的良性循环  相似文献   
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