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1.
中超联赛自2017赛季推出U23新政以来备受争议。在"上有政策下有对策"的非合作博弈下,U23新政如何才能实现政策初衷?该文首次采用不完全信息静态博弈模型分析了U23新政下足协与俱乐部的博弈均衡。研究表明:(1)足协推行新政的最优概率为俱乐部采取积极策略给足协带来的净收益与消极策略带来的净收益之比,实质上取决于俱乐部的遵从度。(2)在缺乏讨价还价权时,俱乐部对新政采取消极应对策略是为了减少净损失。俱乐部积极应对的最优概率为消极应对的净损失占其与积极应对的加成即期收益损失之和的比值,实为两害相权取其轻。为激励俱乐部采取积极策略,应降低俱乐部消极应对策略的净收益或积极应对策略的加成即期收益。(3)提高U23新政有效性的治标之策是减少U23政策对中下游球队的冲击,实行有差别的U23政策;对U23球员上场时间低于均值的俱乐部,实行等额或超额递减分成机制。治本之策是培育一个可预期、可持续、可盈利的足球市场,俱乐部能够内生出建立百年基业的长效机制;继续深化足协的去行政化改革,使之向完全社团法人转型。  相似文献   
2.
Through this study we compared different informants and different behavior screening tools that are available to screen for behavioral and emotional risk. We examined screening results from 100 students from a high school with a high achiever's magnet program in the Southeastern United States (school demographics: 71% female and 79% black, non-Hispanic). This school conducted behavior screening using both teacher-report via the Student Risk Screening Scale, Internalizing/Externalizing (SRSS-IE) and student report via the Strengths and Difficulties Questionnaire (SDQ). Nonparametric correlation tests were conducted between the SRSS-IE and SDQ externalizing and internalizing scores. Generalized linear regression models were created based on the data (demographics, internalizing, and externalizing scores on both screening tools) to model the two count outcomes (office discipline referrals [ODRs] and absences). Diagnostic accuracy metrics were generated from the scores on both the SRSS-IE and SDQ with the outcome measures (ODRs and absences). Externalizing scores on both screening tools had statistically significant low correlations. The ODR model contained two predictors: externalizing score on the SRSS-IE and internalizing score on the SDQ, while the absence model contained grade and the externalizing score on the SDQ. The highest accuracy and agreement values were seen between students with elevated risks on both screening measures and ODRs. The results confirmed that teacher and student reporting, as well as different screening tools, will result in some different students being identified. The choice of informant and screening tools should be dependent on the needs and resources of the school.  相似文献   
3.
The frequent occurrence of security incidents in ride-sharing is a challenge for the survival of IT-enabled ride-sharing platforms. Passengers’ protective behavior is an effective means to alleviate this issue, with benefits to both the passengers and the platforms. This study explores the mechanisms of passengers’ protective behavior in the ride-sharing context by combining protection motivation theory (PMT) and usage situation theory. We test our hypotheses using data (n = 346) collected from a field survey based on a real scenario. The findings reveal that PMT and usage situation theory work well to explain passengers’ protective behavior during ride-sharing. This study explains the motivation behind passengers’ protective behavior in the ride-sharing context, extends the contents of PMT by exploring its antecedents, and extends the contents of usage situation theory by introducing a new dimension. Our findings can help ride-sharing platforms take appropriate strategies to improve passengers’ protective behavior.  相似文献   
4.
电子竞技(E-sports)已经成为当代发展最快,且最重要的文化现象之一。国家体育总局于2003年将它列为第99个运动项目,又在2011年再次将电子竞技改为正式比赛项目。电子竞技从运动员、观众和经济价值而言,是一个不断发展的产业,而且它将被列入2024年巴黎奥运会。虽然最初主要是年轻男性对电子竞技感兴趣,但电子竞技有可能在更广泛的用户群体中带来健康行为的改变。本文运用文献资料法,对比分析法和逻辑分析法探讨电子竞技在整个生命周期内影响健康行为以及一些主要困境的解决措施。除此之外,电子竞技将有可能帮助于个人改变其体育活动和健康行为。最后考虑到电子竞技的指数增长,对于学者和政策制定者来说,认识到电子竞技带来的机遇是非常重要的。  相似文献   
5.
Abstract

The Mystery Room is an educational escape room based on information literacy and applied to multiple audiences, including first-year students and library student employees. In this article, we explain how we developed the game, its theoretical underpinnings, and why it’s a flexible workshop for a variety of audiences.  相似文献   
6.
在计划行为理论(TPB)的基础上,引入身体活动习惯行为与执行意向,构建扩展TPB(METPB)模型,检验该模型对9~19岁青少年群体的中高强度身体活动(MVPA)的适用性,探讨该模型对小学、初中及高中阶段青少年MVPA影响的差异。结果显示:假设模型的拟合度可以接受,纳入习惯行为与执行意向后,METPB显著地提高了其对身体活动行为的解释力。态度和感知行为控制对MVPA行为意向有显著性影响,解释了31.4%的行为意向方差;行为意向和习惯行为对MVPA行为有显著性影响,解释了18.7%的行为方差;执行意向加强了行为意向朝实际行为的转换。METPB模型对于不同学习阶段青少年MVPA意向及行为的影响有显著性差异。其中:主观规范对小学生与初中生MVPA意向产生了显著性影响,而对高中生的MVPA意向并无显著性影响;感知行为控制对3个阶段学生的MVPA意向产生的影响随着学习阶段的上升不断增强。建议:在对于青少年身体活动的干预中,政府、家庭、学校应重视培养学生对于身体活动参与的正确态度,提高其参与身体活动的意愿,培养其参与身体活动的行为习惯,且在对青少年身体活动干预时考虑学习阶段的差异。  相似文献   
7.
体力活动和静坐行为是影响儿童早期体质健康的重要因素。本研究以152名学前儿童为被试,使用三轴加速度计测量体力活动和静坐行为,使用儿童型人体成分分析仪测量身体成分,使用《国民体质测定标准(幼儿部分)》测评身体素质,使用相关分析、多元回归分析和等时替代回归分析对它们之间的关系进行探究,结果发现在控制了性别、年龄、城乡、佩戴时间和静坐行为等因素后,中高强度体力活动尤其是高强度体力活动对去脂体重指数和身体素质(十米折返跑、立定跳远、双脚连续跳、走平衡木)依然具有显著影响;高强度体力活动替代其他强度体力活动或不同强度体力活动替代静坐行为后,去脂体重指数均有所提升;身体素质变化仅在高强度体力活动替代其他强度体力活动和静坐行为时具有方向一致性和显著性。家长和教师应充分重视中高强度体力活动尤其是高强度体力活动与学前儿童体质健康的紧密联系,促进学前儿童静坐行为和低强度体力活动向中高强度体力活动适度转化,以提升学前儿童下肢肌肉力量素质和灵敏素质等方面的体质健康水平。  相似文献   
8.
In this work, we present the first quality flaw prediction study for articles containing the two most frequent verifiability flaws in Spanish Wikipedia: articles which do not cite any references or sources at all (denominated Unreferenced) and articles that need additional citations for verification (so-called Refimprove). Based on the underlying characteristics of each flaw, different state-of-the-art approaches were evaluated. For articles not citing any references, a well-established rule-based approach was evaluated and interesting findings show that some of them suffer from Refimprove flaw instead. Likewise, for articles that need additional citations for verification, the well-known PU learning and one-class classification approaches were evaluated. Besides, new methods were compared and a new feature was also proposed to model this latter flaw. The results showed that new methods such as under-bagged decision trees with sum or majority voting rules, biased-SVM, and centroid-based balanced SVM, perform best in comparison with the ones previously published.  相似文献   
9.
[目的/意义] 随着中国逐步进入老龄化社会,越来越多的老年人使用移动社交网络来丰富自己的生活,调查数据显示微信已成为拥有老年用户数量最多的移动社交网络,构建微信老年用户群体画像对促进老年人提升移动互联网时代的社交能力,提升老年人生活幸福感具有重要意义。[方法/过程] 通过移动终端日志追踪软件获取微信老年用户使用日志数据,并构建实验环境、布置实验内容获取老年用户使用能力数据,利用k-means算法对数据结果进行聚类分析,并对老年用户属性及使用行为数据进行讨论分析。[结果/结论] 基于老年用户画像体系中的用户属性及行为数据聚类结果深入分析微信老年用户行为特征,发现微信老年用户与其他用户群体相比使用强度、交互强度、使用能力偏低;而且微信老年用户群体具有显著差异性,学历越高的老年用户使用能力、交互强度、使用强度越高,即微信活跃老年用户多为高学历用户。根据微信老年用户行为特征制定中国老龄化社会发展中针对老年人的相关社会引导政策具有理论和实践意义。  相似文献   
10.
This study employed fixed effects regression that controls for selection bias, omitted variables bias, and all time-invariant aspects of parent and child characteristics to examine the simultaneous associations between neighborhood disorganization, maternal spanking, and aggressive behavior in early childhood using data from the Fragile Families and Child Wellbeing Study (FFCWS). Analysis was based on 2,472 children and their mothers who participated in Wave 3 (2001–2003; child age 3) and Wave 4 (2003–2006; child age 5) of the FFCWS. Results indicated that higher rates of neighborhood crime and violence predicted higher levels of child aggression. Maternal spanking in the past year, whether frequent or infrequent, was also associated with increases in aggressive behavior. This study contributes statistically rigorous evidence that exposure to violence in the neighborhood as well as the family context are predictors of child aggression. We conclude with a discussion for the need for multilevel prevention and intervention approaches that target both community and parenting factors.  相似文献   
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