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81.
In many important application domains, such as text categorization, scene classification, biomolecular analysis and medical diagnosis, examples are naturally associated with more than one class label, giving rise to multi-label classification problems. This fact has led, in recent years, to a substantial amount of research in multi-label classification. In order to evaluate and compare multi-label classifiers, researchers have adapted evaluation measures from the single-label paradigm, like Precision and Recall; and also have developed many different measures specifically for the multi-label paradigm, like Hamming Loss and Subset Accuracy. However, these evaluation measures have been used arbitrarily in multi-label classification experiments, without an objective analysis of correlation or bias. This can lead to misleading conclusions, as the experimental results may appear to favor a specific behavior depending on the subset of measures chosen. Also, as different papers in the area currently employ distinct subsets of measures, it is difficult to compare results across papers. In this work, we provide a thorough analysis of multi-label evaluation measures, and we give concrete suggestions for researchers to make an informed decision when choosing evaluation measures for multi-label classification.  相似文献   
82.
Five hundred million tweets are posted daily, making Twitter a major social media platform from which topical information on events can be extracted. These events are represented by three main dimensions: time, location and entity-related information. The focus of this paper is location, which is an essential dimension for geo-spatial applications, either when helping rescue operations during a disaster or when used for contextual recommendations. While the first type of application needs high recall, the second is more precision-oriented. This paper studies the recall/precision trade-off, combining different methods to extract locations. In the context of short posts, applying tools that have been developed for natural language is not sufficient given the nature of tweets which are generally too short to be linguistically correct. Also bearing in mind the high number of posts that need to be handled, we hypothesize that predicting whether a post contains a location or not could make the location extractors more focused and thus more effective. We introduce a model to predict whether a tweet contains a location or not and show that location prediction is a useful pre-processing step for location extraction. We define a number of new tweet features and we conduct an intensive evaluation. Our findings are that (1) combining existing location extraction tools is effective for precision-oriented or recall-oriented results, (2) enriching tweet representation is effective for predicting whether a tweet contains a location or not, (3) words appearing in a geography gazetteer and the occurrence of a preposition just before a proper noun are the two most important features for predicting the occurrence of a location in tweets, and (4) the accuracy of location extraction improves when it is possible to predict that there is a location in a tweet.  相似文献   
83.
运用文献资料、专家访谈和逻辑分析等方法,以布迪厄场域理论为基础,以北京体育大学为例,对高校图书馆场域中行动者的资本和惯习等进行了详细分析。通过研究,得出以下结论,高校图书馆管理者的权力资本在高校图书馆场域中占据支配地位,管理者和工作人员技能资本的不足使高校图书馆的服务质量有待提升,作为经济资本持有者之一的大学生在师道尊严的惯习下知识学习和技能习得诉求未得到很好的满足。因此,高校图书馆要从弱化图书馆管理者的权力资本、构建新型的师生关系、提高图书馆管理者和工作人员的技能资本、激发大学生主观能动性的发挥等几个方面促进图书馆的建设与发展,真正体现“读者第一、服务至上”的图书馆管理理念,从而使高校图书馆真正成为学生知识学习、技能掌握、科研创新的第二课堂。  相似文献   
84.
在SWOT总体框架下运用德尔菲法和层次分析法等一些研究方法,去构建研究高校潜水可持续发展的体系,并确立其因素的权重。结果表明从SWOT分析方面去构建一级四个指标优势S、劣势W、机会O、威胁T,二级指标18个因素的体系是能够分析出哪个因素的权重更大,能给予一定的定量分析支持。其中一级指标的优势S是四个指标中最重要的一个因素,能给予决断层学术上的帮助。  相似文献   
85.
In recent years, the transnational movement of people has resulted in increasing tension and debates about national identity. The present research utilized a discourse analytic approach to examine accounts of national identity in the U.S. among native-born U.S. residents, Mexicans living in Mexico, and Mexicans living in the U.S. Our analysis focused on two sets of diverging accounts of national identity. A first set involved participants' explanations of national identity as natural/essential, “felt”, or conditional, which served to either constrain how “American” immigrants could be or allowed for a more inclusive definition of national identity. A second set of accounts involved participants theorizing the national polity as a multicultural or monocultural space which functioned to construct national boundaries as permeable or reinforced (White) American dominance. These patterns of talk emerged across all interviews, although U.S. participants attended to more flexible and dilemmatic (e.g. inclusionary and exclusionary) accounts of national identity. We discuss the implications for the complexity of national identity.  相似文献   
86.
It was examined whether cooperative learning within the Success for All (SfA) program led to improved group work behaviour of Grade 1 pupils. 168 pupils of six SfA schools and 144 pupils of four control schools participated. Positive and negative group work behaviour was observed during a group task, taking into account socioemotional ethos, group participation, and type of dialogue. Longitudinal multilevel analysis was used for the sequence of observed 20-s time intervals. SfA groups showed more positive and less negative group work behaviour compared to control groups, whilst controlling for several group characteristics. Results suggest that negative group work behaviour increased gradually during the whole task in control groups, while in SfA groups it increased only towards the end of the task. The findings indicate that cooperative learning may lead to improved group work behaviour of young pupils (6–7 years old).  相似文献   
87.
Assessment is a crucial part of degree programmes in higher education. While previous research has been primarily concerned with PhD thesis assessment practice in western countries, this article considers the focus and assessment criteria of 40 examiner reports on master’s dissertations in translation studies at a Chinese university. The results indicate that these examiners structured their reports in four rhetorical moves: ‘preparing the candidate for a decision’, ‘expressing an evaluation’, ‘conveying the decision’, and ‘making recommendations’. These examiners appeared to place more emphasis on the expression of ideas, rather than on the accuracy and originality of those ideas. They apparently adopted flexible working criteria, assessing the dissertations based on institutional requirements and on their own experience. This article concludes with a discussion of implications for dissertation writing.  相似文献   
88.
Student hand-raising is an everyday behavior in classroom interactions with teachers. This research presents two studies that examine the variance in hand-raising and its relation to student motivation in two school subjects, Mathematics and Language Arts. Student hand-raising is introduced as an indicator of behavioral engagement. Study 1 investigated N = 397 high school students in 20 classrooms during a videotaped lesson in each subject. Multilevel regression analysis suggests that student motivation accounts for significant variance in hand-raising. The results show subject-specific differences: Student self-concept predicts hand-raising in Mathematics, while students' situational interest predicts their hand-raising in Language Arts. Students’ externally regulated motivation is predictive across both subjects. In Study 2, N = 14 high school students were interviewed about their hand-raising behavior. The results validate and extend the findings from Study 1. Finally, this research emphasizes the importance of fostering student hand-raising and discusses the implications for future research.  相似文献   
89.
海城尚氏祭祖自清初至今已有三百余年。平南王尚可喜于晚年开始着手编著尚氏宗谱,定祖训,及至尚王逝世,宗祠、陵园逐渐修建,尚氏家族的祭祖仪式逐日发展完善。随着时代的发展,尚氏家祭仪式也有所损益,宗谱文化与社会更加契合融汇,具有了更为广泛的文化内涵。  相似文献   
90.
大学生心理问题和思想问题既相互区别又相互联系,高校辅导员对于两类性质各异的问题要采用不同的策略。大学生思想问题的分析和疏导可以采用“思想分析”的方法,思想分析继承和发展了马克思主义分析问题的思想方法,分析的过程也是开解思想“症结”的过程,“解惑、去苦”中运用的方法和技术有“宁静法”“四阶段法”“认知颖悟法”等。  相似文献   
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