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951.
Identifying and accessing reliable, relevant consumer health information rapidly on the Internet may challenge the health sciences librarian and layperson alike. In this study, seven search engines are compared using representative consumer health topics for their content relevancy, system features, and attributes. The paper discusses evaluation criteria; systematically compares relevant results; analyzes performance in terms of the strengths and weaknesses of the search engines; and illustrates effective search engine selection, search formulation, and strategies. 相似文献
952.
Debasis?GangulyEmail authorView authors OrcID profile Gareth?J.?F.?Jones Aarón?Ramírez-de-la-Cruz Gabriela?Ramírez-de-la-Rosa Esaú?Villatoro-Tello 《Information Retrieval》2018,21(1):1-23
Automatic detection of source code plagiarism is an important research field for both the commercial software industry and within the research community. Existing methods of plagiarism detection primarily involve exhaustive pairwise document comparison, which does not scale well for large software collections. To achieve scalability, we approach the problem from an information retrieval (IR) perspective. We retrieve a ranked list of candidate documents in response to a pseudo-query representation constructed from each source code document in the collection. The challenge in source code document retrieval is that the standard bag-of-words (BoW) representation model for such documents is likely to result in many false positives being retrieved, because of the use of identical programming language specific constructs and keywords. To address this problem, we make use of an abstract syntax tree (AST) representation of the source code documents. While the IR approach is efficient, it is essentially unsupervised in nature. To further improve its effectiveness, we apply a supervised classifier (pre-trained with features extracted from sample plagiarized source code pairs) on the top ranked retrieved documents. We report experiments on the SOCO-2014 dataset comprising 12K Java source files with almost 1M lines of code. Our experiments confirm that the AST based approach produces significantly better retrieval effectiveness than a standard BoW representation, i.e., the AST based approach is able to identify a higher number of plagiarized source code documents at top ranks in response to a query source code document. The supervised classifier, trained on features extracted from sample plagiarized source code pairs, is shown to effectively filter and thus further improve the ranked list of retrieved candidate plagiarized documents. 相似文献
953.
A Theory of Media Power and a Theory of Media Use: Different Stories,Questions, and Ways of Thinking
Sandra J. Ball-Rokeach 《Mass Communication and Society》2013,16(1-2):5-40
In this article, I compare the assumptions, concepts, and propositions of media system dependency (MSD) theory and uses and gratifications (U&G) theory at the microlevel of analysis. The epistemological origins of these theories are situated within the differing social and personal contexts that affected their development. Those MSD assumptions that serve as background to this comparison are specified, and major hypotheses concerning the social ecology of microeffects processes are discussed, particularly as they pertain to public opinion concerns. Following this elaboration of MSD theory, basic differences between MSD and U&G conceptions of the audience, interpersonal networks, the media system, and the nature of media power are addressed. I conclude with a brief comment on the implications of the Internet for theorizing micro media effects. 相似文献
954.
955.
Christopher J. Carpenter 《Communication Research Reports》2013,30(2):163-170
A new compliance-gaining technique is introduced called the “just-one-more” (JOM) technique that increases compliance rates by including the phrase “I just need one more person to help.” Two studies are reported (N = 160 in each). The first established the effectiveness of the technique as compared to a direct request. The second tested the hypothesis that goal difficulty moderates the technique's effectiveness in a 2 (JOM or direct request) × 2 (requester needs five surveys or 100). Results indicate that the JOM was substantially more effective than a direct request in the 100 surveys condition but not the five. 相似文献
956.
The paper presents a model that evaluates how upgraded technological capabilities of emerging country based multinationals (EMNCs) and an increase in the domestic market size of large emerging countries affect value chain location choices and the competitiveness of emerging country based firms versus advanced country based ones. The model shows that, even without possessing a competitive advantage in terms of technology and/or brands, EMNCs from large or rapidly technologically advancing countries can become dominant players in the global system. The model highlights the central role of firm level technological intensity and product differentiation in determining the location of value chain activities as well as defining organisational boundaries. Empirical analysis of the location choices of the world's top multinationals from large advanced and emerging countries in 2010 supports the model's predictions. 相似文献
957.
Preschool teachers and classroom aides: Same context,similar perceptions of children's behaviors? 下载免费PDF全文
This study explored the correspondence and differences between school staff perceptions of preschool children's social skills and behavior problems. One hundred preschoolers were assessed by 14 pairs of teachers and classroom aides with the Preschool and Kindergarten Behavior Scales – 2nd Edition (PKBS‐2 Portuguese version). Indexes of agreement and disagreement were calculated. Risk levels and item analyses of PKBS‐2 scores according to both informants' ratings were compared. A higher level of agreement was obtained for social skills scores than for behavior problems (mean correlation of .62). No statistically significant differences between informants were obtained for the risk levels, and item analyses revealed a similar pattern of behaviors that were most and least rated by both informants. Results indicate that the classroom aides' perspective on preschool assessment represents a reliable input, which justifies that they network with teachers in addressing preschoolers' social‐emotional and behavioral challenges. 相似文献
958.
959.
Leonard J. Waks 《Learning Inquiry》2007,1(2):83-87
The topic of listening has been broadly neglected in educational studies. This special issue presents studies on the connections
between listening and reflecting in educational contexts.
相似文献
Leonard J. WaksEmail: |
960.
Depending on the kindness of strangers: current national data initiatives and developmental research 总被引:2,自引:0,他引:2
This article provides a brief review of current large-scale, longitudinal data collection initiatives focusing on children. These studies will be available for secondary data analyses in the twenty-first century. In addition to child outcome data, process-oriented information is being collected on child-parent interactions, quality of child care, elementary school teacher reports and classroom observations, accessibility and use of health, educational and social services, parental mental health, family violence, fathering, parental residence patterns, income and income sources, child support, employment patterns, and community characteristics. Several of these studies are randomized trials of the efficacy of early childhood intervention services and housing mobility programs. The usefulness of these efforts for exploring policy-relevant issues (child support enforcement, work requirements for welfare recipients, antipoverty strategies, housing subsidies and relocation, availability of child care, child-care subsidies) are discussed. 相似文献