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基于ⅡG和LSI组合特征提取方法的文本聚类研究 总被引:3,自引:0,他引:3
本文利用改进的信息增益特征选择方法和潜在语义索引技术组合的特征提取方法,对文本进行了有效的自动聚类.从语料库中抽取了250篇文本,首先利用向量空间模型和改进的信息增益特征选择方法,构造文本特征向量,利用C-均值方法聚类,聚类结果准确率、查全率、F-measure分别达到0.82、0.88、0.83.在此基础上,对最优的特征选择结果运用潜在语义索引方法,对奇异值分解的结果进行截断处理,发现奇异值K取40时聚类结果的准确率、查全率、F-measure达到0.95、0.57、0.78,在有效地降维的同时,大幅度地提高了聚类的准确率. 相似文献
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Question classification systems play an important role in question answering systems and can be used in a wide range of other domains. The goal of question classification is to accurately assign labels to questions based on expected answer type. Most approaches in the past have relied on matching questions against hand-crafted rules. However, rules require laborious effort to create and often suffer from being too specific. Statistical question classification methods overcome these issues by employing machine learning techniques. We empirically show that a statistical approach is robust and achieves good performance on three diverse data sets with little or no hand tuning. Furthermore, we examine the role different syntactic and semantic features have on performance. We find that semantic features tend to increase performance more than purely syntactic features. Finally, we analyze common causes of misclassification error and provide insight into ways they may be overcome. 相似文献
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深圳图书馆创客空间运行模式研究 总被引:1,自引:1,他引:0
[目的/意义]以深圳图书馆创客空间开展的创客系列活动为例,探讨公共图书馆创客空间运行模式,以期为公共图书馆开展创客空间服务提供理论指导与方法参考。[方法/过程]通过研究深圳图书馆创客空间的服务定位、服务对象、服务支撑、服务内容、合作模式、管理机制等内容,探讨公共图书馆创客空间的运行模式。[结果/结论]公共图书馆创客空间开展创客教育与服务,应明确服务定位,提供精准服务;融合STEAM(科学science、技术technology、工程engineering、艺术art、数学mathematics)教育,制定跨学科的创客教育课程体系;引进社会资本,推广public-private partnership(PPP)模式。 相似文献
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[目的/意义]旨在确定信息披露行为影响因素,优化电子健康网站生态环境,间接助力"健康中国2030"战略目标的实现。[方法/过程]采用质性研究方法,对访谈资料进行三级编码,抽取影响电子健康网站用户信息披露的17个主范畴及5个核心范畴,并构建电子健康网站用户信息披露行为影响因素模型。[结果/结论]电子健康网站用户信息披露行为主要受到用户感知效用、感知风险、主观规范、服务质量和病情特征影响。其中,感知效用是最重要影响因素,感知风险是次重要影响因素,主观规范是较重要影响因素,服务质量和病情特征是相对不重要影响因素。据此,从政府部门、电子健康网站和用户3个维度,总结相关启示。 相似文献
78.
There are three models for community archives in China. The first one is where community archives are kept in government-funded/government-established museums or archives. The second is where community archives are kept by scholarly organizations such as universities. The third involves the community establishing its own archive. This last model is very unusual in China. The PiCun Culture and Art Museum of Migrant Labor (PCMML) provides an example of this model as it is the only independent community archives focusing on migrant workers in China. This paper explores the emergence and development of PCMML, its impact on community members and challenges faced including funding and staffing, but also those unique to China—PCMML is greatly influenced by a range of national and local government policies and regulations. Conclusions are that survival strategies for independent community archives in China are dependent on three dimensions: the community itself, society and the government. Cultural consciousness of the community is the premise for the establishment and sustainability of independent community archives, and independent community archives can be the public space to cultivate cultural consciousness of community members and thus activates community members’ agency to document, preserve and disseminate their own history. At the same time, independent community archives also need to engage with broader society to avoid involution and gain support and understanding. Independent community archives are constrained by government policies and regulations, so it is essential for them to develop strategic relationships with government. 相似文献
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Textbook vetting and evaluation process intends to ensure that the materials provided are relevant, of the required quality, suitable ad would enhance learning efficiency and effectiveness. The paper investigates the role of publishers and Tanzania Institute of Education (TIE) in the textbooks vetting and evaluation process; examines factors used to vet, evaluate and approve primary and secondary school textbooks in Tanzania and proposes Strategies that would enhance the textbook vetting, evaluation and process. The study used a mixed method research design. Respondents were selected educational publishers; MoEVT, Baraza la Kiswahili Tanzania, TIE, and Publishers Association of Tanzania. Questionnaire and semi- structured interview were used to collect data which were analysed qualitatively and quantitatively. Major findings of the study were; textbooks vetting and evaluation process is not professionally conducted although standard criteria have been established; there is not well established roles among key players involved in the vetting and evaluation process leading to conflict of interest between TIE and the publishers. The study recommends establishing an independent professional evaluation board and a well-defined timetable and effective communication among various players; enacting a book policy and adopting a limited multiple-textbook publishing system. 相似文献
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