人才振兴背景下大学生志愿服务乡村缘由和影响因素分析

志愿服务乡村是社会参与人才振兴战略的重要方式,大学生在其中承担着重要角色。“乡愁文化”和“社会理性”是大学生志愿服务乡村缘由所在;性别、年级、学校类型、了解程度和志愿组织对大学生志愿服务乡村有显著影响。大学生志愿服务的着力点在于智力支持且具有文教活动倾向性,但也存在意愿与行动脱节、认知流于表面、能动性不强、缺乏思想引领以及对小微志愿组织的支持缺位等问题。乡愁文化嵌入大学文化、引入激励机制、打造志愿组织“大家庭”、牢守宣传育人“主阵地”、强化智力支持优势、补齐理论技能短板、关爱“小微组织”成长、构建“三位一体”支撑体系等可有效优化大学生志愿服务乡村。     

网络服务提供者著作权侵权中的双重注意义务

《民法典》侵权责任编对原有通知删除规则进行了科学修正，但事前保护缺位与事后救济程序失范的问题仍然存在。随着网络服务提供者完成角色转型和技术升级，其作为网络侵权风险的控制者和参与者，有必要且有能力承担未通知阶段的主动预防义务和已通知阶段的证明材料审查义务，以弥补著作权保护和用户利益保护的漏洞。双重注意义务应分别与网络服务提供者对侵权危险的预期和控制能力以及材料审查能力相适应。未通知阶段之注意义务以技术措施为主要履行方式，其注意标准的认定应综合考量技术水平、服务类型、内容介入程度、是否直接获取收益等要素，未尽该注意义务仅为过错认定的考量因素而非唯一标准，并不必然导致侵权责任。已通知阶段之注意义务仅限于对提交的证明材料进行形式审查和有限的实质审查，尽到此注意义务的，可以免于承担侵权责任。     

Re‐framing the Analysis: A 3‐dimensional Perspective of Prisoners’ Children's Well‐being

This article highlights three dimensions to understanding children's well‐being during and after parental imprisonment which have not been fully explored in current research. A consideration of ‘time’ reveals the importance of children's past experiences and their anticipated futures. A focus on ‘space’ highlights the impact of new or altered environmental dynamics. A study of ‘agency’ illuminates how children cope within structural, material and social confines which intensify vulnerability and dependency. This integrated perspective reveals important differences in individual children's experiences and commonalities in broader systemic and social constraints on prisoners’ children. The paper analyses data from a prospective longitudinal study of 35 prisoners’ children during and after their (step) father's imprisonment to illustrate the arguments.     

Towards Uniformly Efficient Trend Estimation Under Weak/Strong Correlation and Non‐stationary Volatility

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.     

Toward a sociology of global comparative placemaking

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.     

Design selection for strong orthogonal arrays

Strong orthogonal arrays (SOAs) were recently introduced and studied as a class of space‐filling designs for computer experiments. An important problem that has not been addressed in the literature is that of design selection for such arrays. In this article, we conduct a systematic investigation into this problem, and we focus on the most useful SOA(n,m,4,2 + )s and SOA(n,m,4,2)s. This article first addresses the problem of design selection for SOAs of strength 2+ by examining their three‐dimensional projections. Both theoretical and computational results are presented. When SOAs of strength 2+ do not exist, we formulate a general framework for the selection of SOAs of strength 2 by looking at their two‐dimensional projections. The approach is fruitful, as it is applicable when SOAs of strength 2+ do not exist and it gives rise to them when they do. The Canadian Journal of Statistics 47: 302–314; 2019 © 2019 Statistical Society of Canada     

Properties of the weighted log‐rank test in the design of confirmatory studies with delayed effects

Proportional hazards are a common assumption when designing confirmatory clinical trials in oncology. This assumption not only affects the analysis part but also the sample size calculation. The presence of delayed effects causes a change in the hazard ratio while the trial is ongoing since at the beginning we do not observe any difference between treatment arms, and after some unknown time point, the differences between treatment arms will start to appear. Hence, the proportional hazards assumption no longer holds, and both sample size calculation and analysis methods to be used should be reconsidered. The weighted log‐rank test allows a weighting for early, middle, and late differences through the Fleming and Harrington class of weights and is proven to be more efficient when the proportional hazards assumption does not hold. The Fleming and Harrington class of weights, along with the estimated delay, can be incorporated into the sample size calculation in order to maintain the desired power once the treatment arm differences start to appear. In this article, we explore the impact of delayed effects in group sequential and adaptive group sequential designs and make an empirical evaluation in terms of power and type‐I error rate of the of the weighted log‐rank test in a simulated scenario with fixed values of the Fleming and Harrington class of weights. We also give some practical recommendations regarding which methodology should be used in the presence of delayed effects depending on certain characteristics of the trial.     

农村互助型社会养老:中国特色与发展路径

农村互助型社会养老是具有中国特色的社会养老的发展形式，是对农村传统家庭养老的重要补充。它扎根于农村传统的亲邻互助网络，其本质在于经济互助，表现为有组织地发动邻里、志愿等社会力量，充分利用以老年人为主的各类人力资源的闲置时间、资源低成本地相互帮助和服务。社会各界应将其作为重要实施方略，纳入积极应对人口老龄化战略和乡村振兴战略之中。其发展路径可以概括为：以资金互助为基础，以组织动员为抓手，以服务互助为重点，以社区居家养老为主要阵地，创新各类互助养老模式，着力形成稳定多元的资金来源，培育互助队伍，增加互助内容，从无偿到无偿、低偿相结合，探索建立标准规范的服务管理评估制度，机构养老与社区居家养老互联互通，最终尝试建立圈层化、整合化、网络化、制度化的农村互助型社会养老体系。     

Teaching technologies for immigrant children: an exploratory study of elementary school teachers in Russia*

ABSTRACT

Educational institutions are an important setting where psychological, pedagogical, sociocultural, and language adaptation of immigrant children occurs. A number of teaching strategies, practices, approaches, and methods have been described in the literature. In the Russian context, such strategies have been called ‘technologies’. The purpose of the present exploratory study was to describe teaching technologies used by teachers in Russia when working with immigrant students in elementary schools. Responses of forty-five elementary school teachers to open-ended questions describing technologies they use when teaching children with migration backgrounds were analyzed using content analysis. Findings suggest that Russian elementary school teachers used ethno-cultural group, communicative technologies, games, individualized instruction, and differentiated teaching. Many approaches mentioned can be used inclusively with groups of immigrant and non-immigrant students. Importantly, while teachers supplemented classroom instruction with additional Russian language lessons, none mentioned specific techniques for teaching Russian as a non-native language. These findings are discussed in relation to teaching strategies described in the international literature focused on migrant students. Finally, implications for further research are discussed.     

A Bayesian Analysis of Abundance,Trend, and Population Viability for Harbor Seals in Iliamna Lake,Alaska

Harbor seals in Iliamna Lake, Alaska, are a small, isolated population, and one of only two freshwater populations of harbor seals in the world, yet little is known about their abundance or risk for extinction. Bayesian hierarchical models were used to estimate abundance and trend of this population. Observational models were developed from aerial survey and harvest data, and they included effects for time of year and time of day on survey counts. Underlying models of abundance and trend were based on a Leslie matrix model that used prior information on vital rates from the literature. We developed three scenarios for variability in the priors and used them as part of a sensitivity analysis. The models were fitted using Markov chain Monte Carlo methods. The population production rate implied by the vital rate estimates was about 5% per year, very similar to the average annual harvest rate. After a period of growth in the 1980s, the population appears to be relatively stable at around 400 individuals. A population viability analysis assessing the risk of quasi‐extinction, defined as any reduction to 50 animals or below in the next 100 years, ranged from 1% to 3%, depending on the prior scenario. Although this is moderately low risk, it does not include genetic or catastrophic environmental events, which may have occurred to the population in the past, so our results should be applied cautiously.