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51.
The need to cluster small text corpora composed of a few hundreds of short texts rises in various applications; e.g., clustering top-retrieved documents based on their snippets. This clustering task is challenging due to the vocabulary mismatch between short texts and the insufficient corpus-based statistics (e.g., term co-occurrence statistics) due to the corpus size. We address this clustering challenge using a framework that utilizes a set of external knowledge resources that provide information about term relations. Specifically, we use information induced from the resources to estimate similarity between terms and produce term clusters. We also utilize the resources to expand the vocabulary used in the given corpus and thus enhance term clustering. We then project the texts in the corpus onto the term clusters to cluster the texts. We evaluate various instantiations of the proposed framework by varying the term clustering method used, the approach of projecting the texts onto the term clusters, and the way of applying external knowledge resources. Extensive empirical evaluation demonstrates the merits of our approach with respect to applying clustering algorithms directly on the text corpus, and using state-of-the-art co-clustering and topic modeling methods. 相似文献
52.
Nampombe Saurombe 《Archival Science》2018,18(2):119-141
South African higher education curricula are largely Eurocentric, to such an extent that indigenous knowledge is marginalised (Horsthemke in Transform High Educ 2(1)–9, 2017). Consequently, the decolonisation of university curricula has become a necessity. The nationwide ‘FeesMustFall’ student protests in 2015 and 2016 have underlined the need to address this matter urgently. Free quality education and the decolonisation of university curricula were among some of the students’ demands (Le Grange in SAJHE 30(2):1–12, 2016). Fundamentally, decolonising curricula involve a serious investigation of history and the strategising of future actions (Ngulube in Historia 47(2):563–582, 2002). Little is known about the potential role of archives in the process of decolonising higher education curricula in South Africa. Perhaps this can be attributed to a lack of awareness about archives and their significance in South Africa (Sulej in ESARBICA J 33:13–35, 2014). This paper explores the role of archives in the decolonisation of higher education curricula in South Africa. It appears that sub-Saharan scholars rarely consult archives (Onyancha et al. in ESARBICA J 32:67–77, 2013). Therefore, public programming is investigated as a means to get more members of the academic community to use archives as centres of critical inquiry. The relevant literature was consulted and discussed. Unique outreach or public programming initiatives will help the academic community to better understand the significance of archives in the decolonisation process. 相似文献
53.
Against the backdrop of Spain’s Transparency Act, this article discusses the presence or otherwise of a series of document types, proposed as management-related transparency indicators, on 61 (8 national and 53 provincial) historic archive websites. Although examples of good practice were identified, the information provided was found to be scant, in particular as regards lines of action, organisational objectives and yearly reports. The information most commonly provided on the websites included the collection classification chart, service use regulations and citizen charters. The inference drawn was that archives, so intently focused on their role in the application of the Act by the organisations they serve, neglect their own administrative obligations in respect of its provisions. The recommendation is that as government-funded and subsidised public service institutions, historic archives should exercise transparency by furnishing the information stipulated in the Act on their websites. 相似文献
54.
Sumayya Ahmed 《Archival Science》2018,18(3):225-240
The turn to oral history in Qatar and the Arabian (also known as Persian) Gulf is not a rejection of traditional archival authority as has been the case in other parts of the world. In the Gulf, oral history has been embraced out of a desire to fill the silences of the largely unwritten record attributable to previous low levels of literacy and strong oral traditions in the region. Today, oral history is seen as the best method to capture details about traditional ways of life during the pre-oil era. After discussing archival concerns about the evidentiary nature of oral histories, this paper explores how it has come to be a crucial documentation tool in the Gulf, adapted to the specific nation building and cultural heritage priorities of the region. 相似文献
55.
Daniel Maier A. Waldherr P. Miltner G. Wiedemann A. Niekler A. Keinert 《Communication methods and measures》2018,12(2-3):93-118
ABSTRACTLatent Dirichlet allocation (LDA) topic models are increasingly being used in communication research. Yet, questions regarding reliability and validity of the approach have received little attention thus far. In applying LDA to textual data, researchers need to tackle at least four major challenges that affect these criteria: (a) appropriate pre-processing of the text collection; (b) adequate selection of model parameters, including the number of topics to be generated; (c) evaluation of the model’s reliability; and (d) the process of validly interpreting the resulting topics. We review the research literature dealing with these questions and propose a methodology that approaches these challenges. Our overall goal is to make LDA topic modeling more accessible to communication researchers and to ensure compliance with disciplinary standards. Consequently, we develop a brief hands-on user guide for applying LDA topic modeling. We demonstrate the value of our approach with empirical data from an ongoing research project. 相似文献
56.
Facebook is challenging professional journalism. These challenges were evident in three incidents from 2016: the allegation that Facebook privileged progressive-leaning news on its trending feature; Facebook’s removal of the Pulitzer Prize-winning “Napalm Girl” photo from the pages of prominent users; and the proliferation of “fake news” during the US presidential election. Using theoretical concepts from the field of boundary work, this paper examines how The Guardian, The New York Times, Columbia Journalism Review and Poynter editorialized Facebook’s role in these three incidents to discursively construct the boundary between the value of professional journalism to democracy and Facebook’s ascendant role in facilitating essential democratic functions. Findings reveal that these publications attempted to define Facebook as a news organization (i.e., include it within the boundaries of journalism) so that they could then criticize the company for not following duties traditionally incumbent upon news organizations (i.e., place it outside the boundaries of journalism). This paper advances scholarship that focuses on both inward and outward conceptions of boundary work, further explores the complex challenge of defining who a journalist is in the face of rapidly changing technological norms, and advances scholarship in the field of media ethics that positions ethical analysis at the institutional level. 相似文献
57.
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59.
Eisenhauer ER Mosher EC Lamson KS Wolf HA Schwartz DG 《Health information and libraries journal》2012,29(2):152-161
Background: Somali Bantu refugees, with unique health information needs, created challenges for health and social service providers. Objectives: A service innovation was developed (i) to raise awareness, especially among local health and social service providers, about the Bantu refugees’ presence in the community, their culture, and their information needs and (ii) to deliver needed health information, emphasizing child health, to the Bantu mothers in their homes. Methods: The project consisted of: (i) a community conference targeting local health and social service providers, describing the refugees’ presence in the community, their culture, and information needs. (ii) Focus groups conducted with members of the Bantu population elicited additional information needs. (iii) Curriculum was developed based on identified needs, and (iv) the curriculum was delivered to the refugees in their homes. A clinical informationist and MP3 technology enhanced the project. Findings: Conference attendees’ evaluation responses indicated improved understanding of Bantu culture. Focus groups’ identification of health information needs provided a framework for the health education curriculum. A project website made educational materials available to other healthcare providers. Conclusions: The project raised awareness of the Bantus’ presence, culture, and information needs. Identification of other unmet needs demonstrated that additional support for refugees is required. 相似文献
60.
Miller LE Pierson LM Nickols-Richardson SM Wootten DF Selmon SE Ramp WK Herbert WG 《Research quarterly for exercise and sport》2006,77(1):58-63
This study assessed muscular torque and rate of torque development following concentric (CON) or eccentric (ECC) isokinetic training. Thirty-eight women were randomly assigned to either CON or ECC training groups. Training consisted of knee extension and flexion of the nondominant leg three times per week for 20 weeks (SD = 1). Eccentric training increased ECC knee extension and flexion peak torque more than CON training. The ECC group improved acceleration time and time to peak torque with ECC movements versus the CON group. Slow-velocity ECC isokinetic training yielded greater ECC and similar CON torque development gains versus CON training over the course of 20 weeks in young women. 相似文献