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11.
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prediction study for articles containing the two most frequent verifiability flaws in Spanish Wikipedia: articles which do not cite any references or sources at all (denominated Unreferenced) and articles that need additional citations for verification (so-called Refimprove).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   
12.
Self‐reported measures are an easy, time‐efficient, and low‐cost way to collect research data compared to other assessment methods. They are, however, characterized by several limitations regarding the quality and the clarity of the data they produce, especially when they are implemented in education. The main purpose of the current study was to use a method called discrete choice modeling (DCM) in education, in order to develop a self‐reported instrument that will reduce the bias for socially desirable responses and to assess teachers’ practices in physical activity. DCM method has the ability to overcome the respondents’ tendency to answer in a socially desirable way. A nationally representative sample of 531 Greek early educators participated in this study and were administered a self‐assessment questionnaire based on DCM. Results showed that the DCM based newly developed instrument manages to assess effectively educators’ practices and provided evidence of the applicability of the method in education. Further implications and future recommendations regarding the effective application of DCM in education are discussed.  相似文献   
13.
基于深度学习的中文专利自动分类方法研究   总被引:2,自引:0,他引:2  
[目的/意义] 面向当前国内专利审查和专利情报分析工作中对于海量专利分类的客观需求,设计了7种基于深度学习的专利自动分类方法,对比各种方法的分类效果,从而助力专利分类效率和效果的提升。[方法/过程] 针对传统机器学习方法存在的缺陷,基于Word2Vec、CNN、RNN、Attention机制等深度学习技术,考虑专利文本语序特征、上下文特征以及分类关键特征,设计Word2Vec+TextCNN、Word2Vec+GRU、Word2Vec+BiGRU、Word2Vec+BiGRU+TextCNN等7种深度学习模型,以中国专利为例,选取IPC主分类号的"部"作为分类依据,对比这7种模型与3种传统分类模型在中文专利分类任务中的效果。[结果/结论] 实证研究效果显示,采用考虑语序特征、上下文特征及强化关键特征的深度学习方法进行中文专利分类具有更优的分类效果。  相似文献   
14.
王思茗  滕广青 《图书情报知识》2020,(3):109-118,F0003
[目的/意义]领域知识的跨学科交叉研究能够打破学科间的壁垒,有助于发现重大科学问题的解决方案。[研究设计/方法]基于图书情报学领域文献题录信息构建轻量级领域知识图谱,从中提取学科信息、国家信息、时间信息及其关联,采用时间与空间相结合的多维度分析方法,对学科交叉的演化进程以及国家差异进行跟踪与分析。[结论/发现]图书情报学领域内学科交叉现象日渐显著,各国家的学科交叉程度与倾向存在差异,一些目前尚不突出的交叉学科方向值得关注。[创新/价值]采用多维度视角分析学科交叉现象,相关结论可以为国家科技战略制定及学科发展规划提供有益参考。  相似文献   
15.
Review helpfulness is attracting increasing attention of practitioners and academics. It helps in reducing risks and uncertainty faced by users in online shopping. This study examines uninvestigated variables by looking at not only the review characteristics but also important indicators of reviewers. Several significant review content and two reviewer variables are proposed and an effective review helpfulness prediction model is built using stochastic gradient boosting learning method. This study derived a mechanism to extract novel review content variables from review text. Six popular machine learning models and three real-life Amazon review data sets are used for analysis. Our results are robust to several product categories and along three Amazon review data sets. The results show that review content variables deliver the best performance as compared to the reviewer and state-of-the-art baseline as a standalone model. This study finds that reviewer helpfulness per day and syllables in review text strongly relates to review helpfulness. Moreover, the number of space, aux verb, drives words in review text and productivity score of a reviewer are also effective predictors of review helpfulness. The findings will help customers to write better reviews, help retailers to manage their websites intelligently and aid customers in their product purchasing decisions.  相似文献   
16.
本文采用文献综述法和逻辑分析方法,通过对武术神、意、气与动作内外相结合,使身心达到愉悦、全面的发展。武术训练对人的力量、灵敏、柔韧等身体素质的发展都有良好影响,强健体魄,缓解压力,保持一个舒畅愉快的心情。武术套路的训练不仅能塑造强健的身体,而且也承载着道德文化修养和精神传承的历史重任,经过研究和调查,很多青少年通过武术套路训练,提高了其自身的身体素质和顽强不屈的精神品格。  相似文献   
17.
随着新一轮教改工作在我国全国范围内的深入开展,体育已经成为各地小学素质教育工作中的重点内容。就目前来看,为进一步提高小学体育教学效率,兴趣化游戏教学已经逐步被引入实际教学工作中,该教学模式可以冲破传统教条主义教学思维的拘束,进一步提高学生对学习的兴趣,使被动学习转变为主动学习,从而更好地实现当今时代小学体育教学工作目标。  相似文献   
18.
随着体育的发展,模块教学理念深入学校的体育教学之中。模块教学是以学生为主体的教学模式,学生能够根据自己的特长和爱好选择适合自己的体育运动项目,从而保障了学习体育的积极性。针对于今天的教学来说,教师的教学目的一定不是单纯地去追求学生的学习成绩,今天随着新课标的不断深入,教师需要把以往从学生纯净的追求转变为对于学生综合素养的追求。这个时候体育学科的重要性就会有所体现,身体是革命的本钱,学生在学习的过程中一定要有一个好的身体素质,只有这样他们才能够更好地应对接下来的生活。  相似文献   
19.
随着现代教育的不断推进,在阳光体育的背景下,体育备受教育部门和学校的关注。本文针对学校体育教学中存在的一些问题,结合学校体育的发展的特点,让分层教学模式走进学校体育的课堂,通过分层教学,打破了传统的"一锅煮"的教学模式,让不同层次的学生通过自己不懈的努力,体育成绩都能得到发展。通过这样的教学模式,不仅把学生的眼球吸引到体育教学的课堂,而且促进学生体育学习的积极性,使得体育课堂活起来,为学生的终身体育学习打下良好的基础。  相似文献   
20.
In an expertise study with 94 mathematics teachers varying in their relative teacher expertise (i.e., student teachers, trainee teachers, in-service teachers), we examined effects of teachers' professional knowledge and motivational beliefs on their ability to integrate technology within a lesson plan scenario. Therefore, we assessed teachers' professional knowledge (i.e., content knowledge, pedagogical content knowledge, technological knowledge), and their motivational beliefs (i.e., self-efficacy, utility-value). Furthermore, teachers were asked to develop a lesson plan for introducing the Pythagorean theorem to secondary students. Lesson plans by advanced teachers (i.e., trainee teachers, in-service teachers) comprised higher levels of instructional quality and technology exploitation than the ones of novice teachers (i.e., pre-service teachers). The effect of expertise was mediated by teachers' perceived utility-value of educational technology, but not by their professional knowledge. These findings suggest that teachers’ motivational beliefs play a crucial role for effectively applying technology in mathematics instruction.  相似文献   
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