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991.
Jason A. Martin Jessica Gall Myrick Kimberly K. Walker 《Mass Communication and Society》2017,20(5):614-636
This experiment integrated theory from multiple domains to examine how aspects of news coverage of the Affordable Care Act (ACA) and differences in participants’ cognitive and emotional contingent conditions interact to shape attitudes and behavioral intentions toward health care legislation. Using a sample of uninsured young adults (N = 1,056), we tested an affective mediation model, which assessed the mechanisms through which media frames, exemplar case studies, and individual predispositions affect this type of news consumer. Results demonstrate the complicated pathways through which emotions mediate the effects of news coverage of ACA based on political predispositions, the need for orientation toward the health care issue, and the influence of equivalency framing in the form of example cases. These findings contribute to a more nuanced explanation of the causal mechanisms underpinning framing effects of public policy news coverage on an understudied population. The need for further examination of emotion along with cognition when investigating framing effects of public policy news is discussed, and the importance of exemplar cases as a significant manifestation of the effects equivalence framing is highlighted. 相似文献
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Jimmy?Lin Andrew?TrotmanEmail authorView authors OrcID profile 《Information Retrieval》2017,20(3):199-220
This paper explores the performance of top k document retrieval with score-at-a-time query evaluation on impact-ordered indexes in main memory. To better understand execution efficiency in the context of modern processor architectures, we examine the role of index compression on query evaluation latency. Experiments include compressing postings with variable byte encoding, Simple-8b, variants of the QMX compression scheme, as well as a condition that is less often considered—no compression. Across four web test collections, we find that the highest query evaluation speed is achieved by simply leaving the postings lists uncompressed, although the performance advantage over a state-of-the-art compression scheme is relatively small and the index is considerably larger. We explain this finding in terms of the design of modern processor architectures: Index segments with high impact scores are usually short and inherently benefit from cache locality. Index segments with lower impact scores may be quite long, but modern architectures have sufficient memory bandwidth (coupled with prefetching) to “keep up” with the processor. Our results highlight the importance of “architecture affinity” when designing high-performance search engines. 相似文献
994.
Patrons of map collections often have specific, geographically-based, requests for maps and the information they provide. Map librarians can often meet these needs through personal knowledge of the scope of their collections. For larger collections, this method is unsustainable. This article, therefore, seeks to begin a discussion on how coding could be used to expand the ability of our patrons’ online information seeking methods to meet their information needs. 相似文献
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In this paper we introduce a framework for using quality as an incentive to promote proper application level congestion control. Through integrating a joint-source channel coder and feedback-based congestion control scheme, we are able to construct accurate and efficient quality incentives. The framework is applicable in all network architectures where end-to-end congestion control may be used, and is as such not specific to either best-effort or traffic class-based architectures. The concept is presented along with preliminary simulations that highlight the resulting rate control accuracy. We also discuss how to implement some well-known congestion control schemes within our framework. 相似文献
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Justin D. Martin 《Journalism Practice》2016,10(1):93-108
This study examines year-by-year correlations between Freedom House and Reporters Sans Frontières' (RSF) press freedom scores for countries over a 13-year period (2002–2014). The goal of the study is to test the hypothesis that, further into the age of digital disclosure, as press abuses and harassment of journalists are more widely reported, press freedom ranking systems are gradually becoming more precise and, therefore, correlations between the two indices will strengthen over time. To further assess concurrent validity of the indices, correlations between both indices and scores on the United Nations Human Development Index are also provided. The study also examines changes in the indices' rankings of countries over time within six world regions: the Middle East and North Africa, the Americas, Western Europe, Eastern Europe/Central Asia, Sub-Saharan Africa, and Asia. In so doing, this study adds a degree of understanding to the validity of two press freedom indices that are routinely cited in journalistic reportage and trade journals, as well as many scholarly publications. Results suggest that the two organizations' scoring of press freedom has become significantly more correlated in the years 2002–2014, and the primary cause of the increased agreement is that RSF's ratings became substantially more aligned with Freedom House's scores during this period. Both indices' ratings are significantly correlated with countries' United Nations Human Development Index scores. 相似文献
1000.
Andrew J. Perrin 《The Communication Review》2016,19(1):55-76
This paper analyzes the argumentative style and the characteristics of writers of newspaper letters to the editor. Writers are more likely to be White, male, older, more politically active, and less likely to be politically moderate than the local population. Inequality in political participation persists in this forum. Gender and sense of local political efficacy influence how letter writers make their points. Letters to the editor mostly display inequalities similar to other forms of political participation. 相似文献