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1.
目前在文献中有很多关于多响应比较的研究方法,但是对带协变量调整的非参数检验的研究较少。一种直观的想法是将数据先投影到协变量的正交空间中,然后再利用秩和检验、调整的秩和检验或最大值检验方法。但是,功效普遍不高。在调整的秩和检验和伪F检验两种方法基础上,构建MIN2检验。大量模拟和实际数据表明,MIN2检验的效果优于现有的非参数检验方法。  相似文献   
2.
从分析供需匹配之间存在的冲突入手,提出一种基于图模型冲突分析法来求解供需匹配问题的思路。首先在图模型视角下给出供需匹配问题的研究框架,分析不同类型的供需匹配问题,设定决策主体和决策策略;然后讨论不同匹配类型下的状态约简、偏好表达,进行稳定性分析;最后通过应用案例,将图模型法与群决策匹配算法进行对比分析,验证图模型求解供需匹配问题的有效性。  相似文献   
3.
BackgroundAdverse childhood experiences (ACEs) are a potent risk factor. Despite these findings, studies have also recognized the importance of considering additional sources of genetic and environmental influence that cluster within families.ObjectiveTo properly control for latent sources of genetic and within-family environmental influences and isolate the association between ACEs and the following outcomes in adulthood: physical health, depressive symptoms, educational attainment, income attainment, alcohol problems, and antisocial behavior.Participants and SettingTwo independent samples of twins and siblings from the United States: the Midlife Development in the United States (MIDUS) study (N = 862) and the National Longitudinal Study of Adolescent to Adult Health (Add Health; N = 3112).MethodsSibling comparison models, which control for latent sources of genetic and within-family environmental influences, were estimated to examine whether differential exposure to ACEs was associated with the examined outcomes.ResultsFamilies that experienced more adversity also experienced more deleterious outcomes. However, siblings that experienced more adversity were no more likely to experience deleterious outcomes than their co-siblings. However, greater exposure to ACEs was associated with increases in depressive symptoms (Add Health). Additional models revealed that the similarity between siblings from the same family stemmed from latent sources of within-family environmental influences not captured by traditional ACEs measures.ConclusionsConsidering genetic influences and additional latent sources of within-family influences is crucial in isolating the effects of ACEs. Currently employed ACEs measures may not adequately capture the full range of impactful sources of family-level environmental influence.  相似文献   
4.
Jie Zhang 《国际体育史杂志》2018,35(12-13):1356-1368
Abstract

This article explores Chinese chui wan from its earliest manifestation during the Tang Dynasty, through its development, prosperity, and decline during the Qing Dynasty. The similarities and differences between chui wan and early forms of golf in Scotland are compared from a cross-cultural perspective to explore the relationship between these two cultural phenomena. While the two games had very different origins and there is no clear evidence of exposure to chui wan in Scotland, the games themselves were remarkably similar in terms of rules, equipment, venues, and player roles. It is not understood why chui wan disappeared from Chinese society, but it is likely that the development and organizational support of the two games, as well as the cultural and political contexts in which they existed, have resulted in different trajectories for Chinese chui wan and golf. Whilst chui wan has faded away, golf has become a popular game around the world.  相似文献   
5.
刘容 《中国名城》2020,(4):28-33
文化创意城市发展模式对全球城市应对后工业化困境功效卓著。首先,描绘国外文化创意城市概念从“萌生”到“成熟”的路径衍化。其次,总结了国内外著名文化创意城市,维也纳、哥本哈根、巴黎、伦敦、北京、上海、深圳和杭州的发展经验。再次,从目的、方向、路径等方面通过比较视角梳理国内外文化创意城市建设的差异。最后,总结对我国文化创意城市建设的启示,认为应将文化创意城市发展融入城市总体发展规划,大力促进当前“双创工作”深入开展,并在充分尊重城市历史文化基础上凝聚市民大众共识,形成文化创意城市发展方向,来促进我国文化创意城市的发展。  相似文献   
6.
[目的/意义]为了深入了解科研众筹平台中的项目情况,本文对科研众筹项目的基本特征、研究主题和不同类型科研众筹项目的属性对比进行研究。[研究设计/方法]首先对科研众筹的起源、价值和运作模式进行了梳理;随后爬取了科研众筹平台Experiment的项目信息,并对该平台中科研项目的发起者、背书者、项目记录、所属学科、资助情况等进行特征描述;基于LDA模型对科研众筹项目主题进一步细化,并对不同资金筹集和不同主题分类情况下的科研众筹项目的属性差异进行比较分析。[结论/发现]科研众筹主题主要集中在生物学和生态学两个领域,不同资金筹集达成情况的科研众筹项目在项目背书者数量、信息记录次数和讨论次数上具有显著差异;不同主题的科研众筹项目在其讨论次数上具有显著差异。同时,是否提供视频和是否参与资助挑战在不同资金筹集达成情况和不同主题的科研众筹项目上均具有显著差异。[创新/价值]深入分析了科研众筹平台中项目主题及属性对比情况,对科研众筹平台优化信息审核机制、社交机制和信息展示机制具有一定的参考价值。  相似文献   
7.
文章梳理李芳馥在文华图书科、哥伦比亚大学图书馆学院、芝加哥大学图书馆学研究院的求学经历,在国立北平图书馆、美国国会图书馆、哥伦比亚大学图书馆、国立北平图书馆上海办事处、沪江书院图书馆、上海图书馆等处的工作履历,在国立社会教育学院图书博物馆学系与华东师范大学图书馆学系兼任教职的经过。李芳馥为中国图书馆事业做出了重要贡献,推动了中美图书馆界交流合作。  相似文献   
8.
Continued advancement in the field of physical activity and health promotion relies heavily on the synthesis of rigorous scientific evidence. As such, systematic reviews and meta-analyses of randomized controlled trials have led to a better understanding of which intervention strategies are superior (i.e., produce the greatest effects) in physical activity-based health behavior change interventions. Indeed, standard meta-analytic approaches have allowed researchers in the field to synthesize relevant experimental evidence using pairwise procedures that produce reliable estimates of the homogeneity, magnitude, and potential biases in the observed effects. However, pairwise meta-analytic procedures are only capable to discerning differences in effects between a select intervention strategy and a select comparison or control condition. In order to maximize the impact of physical activity interventions on health-related outcomes, it is necessary to establish evidence concerning the comparative efficacy of all relevant physical activity intervention strategies. The development of network meta-analysis (NMA)—most commonly used in medical-based clinical trials—has allowed for the quantification of indirect comparisons, even in the absence of direct, head-to-head trials. Thus, it stands to reason that NMA can be applied in physical activity and health promotion research to identify the best intervention strategies. Given that this analysis technique is novel and largely unexplored in the field of physical activity and health promotion, care must be taken in its application to ensure reliable estimates and discernment of the effect sizes among interventions. Therefore, the purpose of this review is to comment on the potential application and importance of NMA in the field of physical activity and health promotion, describe how to properly and effectively apply this technique, and suggest important considerations for its appropriate application in this field. In this paper, overviews of the foundations of NMA and commonly used approaches for conducting NMA are provided, followed by assumptions related to NMA, opportunities and challenges in NMA, and a step-by-step example of developing and conducting an NMA.  相似文献   
9.
运用双框架模型对中美竞技体育国际竞争力进行比较研究。认为:①从显现性框架分析,美国竞技体育国际竞争力一直稳定处于高位,而中国则呈现以2008年为峰顶的倒“U”型发展特征,且与美国还存在一定差距;②从解释性框架分析,美国竞技体育国际竞争力已趋于顶峰,而中国稳步提升;③中国竞技体育发展潜力巨大,但短时间内难以赶超美国;④“举国体制”有利于中国竞技体育显现性竞争力的提升,但与美国社会办竞技体育的发展模式相比,市场、社会在竞技体育发展中的作用发挥不足,不利于高经济性项目、高欣赏性项目的发展;⑤坚持“举国体制”、承办2022年冬奥会有利于中国竞技体育显现性竞争力的提升和冬季项目的发展,但同样存在竞技体育项目布局转型的困难和群众体育基础薄弱的困境。  相似文献   
10.
In this ITEMS module, we introduce the generalized deterministic inputs, noisy “and” gate (G‐DINA) model, which is a general framework for specifying, estimating, and evaluating a wide variety of cognitive diagnosis models. The module contains a nontechnical introduction to diagnostic measurement, an introductory overview of the G‐DINA model, as well as common special cases, and a review of model‐data fit evaluation practices within this framework. We use the flexible GDINA R package, which is available for free within the R environment and provides a user‐friendly graphical interface in addition to the code‐driven layer. The digital module also contains videos of worked examples, solutions to data activity questions, curated resources, a glossary, and quizzes with diagnostic feedback.  相似文献   
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