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21.
Charles Mackay 《出版经济》2006,(8):32
在中世纪的欧洲,曾经出现被后人称为欧洲历史上最荒唐的群众狂潮之一:郁金香热.当时社会里人性盲目和疯狂的一面,既贻笑后人,又触目惊心,令人难忘. 相似文献
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Zuckerman: Scientist Extraordinary by Bernard Donovan BioScientifica, Bristol, 2005, 555pp. ISBN 1‐901978249 £24.95 Negotiating licences for digital resources by Fiona Durrant Facet Publishing, 2006, ISBN 1 85604 586 2 Metadata for Information Management and Retrieval By David Haynes Facet Publishing, 2004, ISBN 1 85604 4890 相似文献
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This study investigates the perceived impact of election polls,focusing on the hotly contested 2000 U.S. presidential election.Survey data from 558 individuals gathered during the final daysof the election campaign are analyzed to examine beliefs thatthe polls greatly affect other voters, general views of pollsas good or bad for the country, beliefs about whether pollstersinfluence their results to come out a certain way, and supportfor banning election-night projections. Results indicate thatmost respondents felt the polls had no influence on themselveswhile still affecting others. Respondents exhibiting these third-person-effectperceptions were significantly more likely than others to believethat election polls are a bad thing for the country. Negativeperceptions of polls and beliefs that pollsters try to influenceresults were also related to general distrust of the news media.Negative views of polls in turn were associated with increasedsupport for prohibiting election-night projections. In general,the results illustrate the dependency of negative views aboutpolling on fears of untoward effects on voters, in particularthe fear that polls and election projections might lend supportto candidates opposed by the respondent. 相似文献
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This article explores the evolution of the role of academic journal articles submitted to the UK's Research Assessment Exercise (RAE). By reviewing their role, it is possible to see how the changes from quantitative to qualitative assessment (and the resulting problems surrounding the definition of ‘quality’ journals) has impacted both on the journals selected by academics for publishing their research and the assessment of them. Although only one part of RAE submissions, the listing of published research outputs provides the primary evidence for research quality to most RAE panels, and is a significant driver of the final grade awarded, and thus the funding received by submitting institutions. The RAE, being a peer‐reviewed assessment exercise, mirrors in some ways the peer‐review process immured within scholarly publication. The developing role of journal publications as a vehicle for academic research output is examined via the chronology of the RAE, before assessing the current situation in which published journal output formed almost 70% of all output assessed by RAE panels in the latest exercise. The impact of this increased importance of academic journals in the assessment process is considered not only for academics but also for the wider community, i.e. publishers and libraries. 相似文献
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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
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A number of voices have emerged in U.S. political discourse questioning the legitimacy of American exceptionalism, suggesting we are in a “post-American world.” Our research examines the effects that political messages that explicitly challenge American exceptionalism can have on U.S. public opinion. Drawing upon social identity theory, we find that explicit challenges to American exceptionalism significantly impact Americans’ views toward their own nation, their willingness to denigrate foreign publics, and their broader foreign policy preferences. 相似文献
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