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1.
In social networking services (SNSs), users’ unclear understanding of the large and invisible audience increases the chances of online turbulence, which is a key source of SNS-induced stress. This growing phenomenon has gained increasing attention in academia and industry due to the undesirable consequences for users and SNS platforms. In this study, we draw from the transactional model of stress to examine how audience management strategies impact online turbulence and lead to neglected unintended audience concern and lurking. We also investigate the role of self-monitoring as a stress inhibitor. We test our model with data collected from 301 SNS users. The results show that the four types of audience management strategies have different effects on online turbulence, which significantly impacts neglected unintended audience concern especially when users have high self-monitoring skills. We believe that this work contributes, both from scientific and practical standpoints, to the understanding of the interventions and stressful responses of online turbulence in SNSs.  相似文献   
2.
Community question answering (CQA) services that enable users to ask and answer questions are popular on the internet. Each user can simultaneously play the roles of asker and answerer. Some work has aimed to model the roles of users for potential applications in CQA. However, the dynamic characteristics of user roles have not been addressed. User roles vary over time. This paper explores user representation by tracking user-role evolution, which could enable several potential applications in CQA, such as question recommendation. We believe this paper is the first to track user-role evolution and investigate its influence on the performance of question recommendation in CQA. Moreover, we propose a time-aware role model (TRM) to effectively track user-role evolution. With different independence assumptions, two variants of TRM are developed. Finally, we present the TRM-based approach to question recommendation, which provides a mechanism to naturally integrate the user-role evolution with content relevance between the answerer and the question into a unified probabilistic framework. Experiments using real-world data from Stack Overflow show that (1) the TRM is valid for tracking user-role evolution, and (2) compared with baselines utilizing role based methods, our TRM-based approach consistently and significantly improves the performance of question recommendation. Hence, our approach could enable several potential applications in CQA.  相似文献   
3.
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   
4.
连殿冬 《当代体育科技》2020,(12):108-108,110
校园足球运动是夯实足球人才的根基,对学生智力发展及身体健康水平的改善与提升具有重要作用。本文以新疆生产建设兵团所属的塔里木大学为具体研究对象,梳理了塔里木大学校园足球运动的发展模式,并在此基础上分析、探讨了塔里木大学校园足球运动推广、管理与发展的成功经验与模式,以及制约塔里木大学校园足球进一步发展的瓶颈。  相似文献   
5.
In the IR field it is clear that the value of a system depends on the cost and benefit profiles of its users. It would seem obvious that different users would prefer different systems. In the TREC-9 filtering track, systems are evaluated by a utility measure specifying a given cost and benefit. However, in the study of decision systems it is known that, in some cases, one system may be unconditionally better than another. In this paper we employ a decision theoretic approach to find conditions under which an Information Filtering (IF) system is unconditionally superior to another for all users regardless of their cost and benefit profiles.It is well known that if two IF systems have equal precision the system with better recall will be preferred by all users. Similarly, with equal recall, better precision is universally preferred. We confirm these known results and discover an unexpected dominance relation in which a system with lower recall will be universally preferred provided its precision is sufficiently higher.  相似文献   
6.
优秀游泳运动员训练监控研究初探   总被引:11,自引:1,他引:10  
在备战 2 0 0 0年第 2 7届奥运会期间 ,采用血乳酸、肌酸激酶等指标对国家游泳队优秀运动员进行了训练监控 ,对磷酸原训练、有氧训练、高原训练模式等进行了探讨 ,为科学训练提供参考依据  相似文献   
7.
对篮球运动员临场心理躁动的涵义与意义、篮球运动员临场比赛进程中心理躁动的具体表现、教练员临场心理调控的意义与方法进行了论述。  相似文献   
8.
中文译著中外国个人责任者标目的选取   总被引:4,自引:1,他引:3  
规范工作是图书馆编目工作中非常重要的一部分。清华大学图书馆现已建立了名称规范文档,实现了规范控制,使得责任者标目的选取日趋规范,进一步增强了书目的检索功能和集中功能。在各种标目的选取中,中文译著中外国个人责任者的标目选取最为复杂,本文将从多方面对此进行探讨,并针对当前工作中存在的具体问题提出建议。  相似文献   
9.
股票投资的方法很多,建立物理模型进行投资是一种简明有效的方法,使用金字塔模型和平衡理论对股票进行操作,能把握最佳投资机会。  相似文献   
10.
采用文献资料法和逻辑分析方法。讨论和分析了在市场经济中政府体育投资行为动机和体育投资过程中常见的行为偏差。主要结论 :政府体育投资的主要动机是 ,满足社会对体育的公共需要 ;维护社会公平 ,实现社会大众参与体育的机会相对均等以及确保体育与经济社会的协调发展等。体育投资行为偏差是 ,社会功利性过强 ;投资稳定性不够以及投资的随意性和盲目性等。纠正体育投资行为偏差的措施是 ,加强体育投资的立法 ;提高体育投资的透明度 ;完善体育投资管理体制和加强社会监督等  相似文献   
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