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991.
Why People Dual Screen Political Debates and Why It Matters for Democratic Engagement 总被引:1,自引:0,他引:1
Dual screening during televised election debates is a new domain in which political elites and journalists seek to influence audience attitudes and behavior. But to what extent do non-elite dual screeners seek to influence others, particularly their social media followers, social media users in general, and even politicians and journalists? And how does this behavior affect short- and longer-term engagement with election campaigns? Using unique, event-based, panel survey data from the main 2015 UK general election debate (Wave 1 = 2,351; Wave 2 = 1,168) we reveal the conditions under which people experience agency, empowerment, and engagement now that social media have reconfigured broadcast political television. 相似文献
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Marina Encheva Plamena Zlatkova Nilgün Özdamar Keskin İlker Vatansever 《International Information and Library Review》2017,49(2):145-161
Welcome to the Global Postcards column! We are so excited to bring you news and projects from around the world. In this column, our contributors from Bulgaria and Turkey bring us a comparative study of mobile and information literacy among students at two universities in those countries. In addition to presenting perceptions of students around these literacy concepts, their research project also highlights growing trends in the use of distance education and web-based study materials. Thanks to the contributors for this issue, and please keep the submissions coming!
If you would like to send a submission, please contact either of the column's co-editors: Jacqueline Solis, jsolis@email.unc.edu, and Robin Kear, rlk25@pitt.edu. 相似文献
994.
Alejandro?BellogínEmail authorView authors OrcID profile Pablo?Castells Iván?Cantador 《Information Retrieval》2017,20(6):606-634
There is an increasing consensus in the Recommender Systems community that the dominant error-based evaluation metrics are insufficient, and mostly inadequate, to properly assess the practical effectiveness of recommendations. Seeking to evaluate recommendation rankings—which largely determine the effective accuracy in matching user needs—rather than predicted rating values, Information Retrieval metrics have started to be applied for the evaluation of recommender systems. In this paper we analyse the main issues and potential divergences in the application of Information Retrieval methodologies to recommender system evaluation, and provide a systematic characterisation of experimental design alternatives for this adaptation. We lay out an experimental configuration framework upon which we identify and analyse specific statistical biases arising in the adaptation of Information Retrieval metrics to recommendation tasks, namely sparsity and popularity biases. These biases considerably distort the empirical measurements, hindering the interpretation and comparison of results across experiments. We develop a formal characterisation and analysis of the biases upon which we analyse their causes and main factors, as well as their impact on evaluation metrics under different experimental configurations, illustrating the theoretical findings with empirical evidence. We propose two experimental design approaches that effectively neutralise such biases to a large extent. We report experiments validating our proposed experimental variants, and comparing them to alternative approaches and metrics that have been defined in the literature with similar or related purposes. 相似文献
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Elizabeth Dorrance Hall John O. Greene Lindsey B. Anderson LaReina Hingson Elizabeth Gill Brenda L. Berkelaar 《Communication Studies》2017,68(5):493-510
“Creative facility” refers to the ease, rapidity, or fluency with which people are able to formulate and produce novel, appropriate messages. Previous research indicates that people differ in this regard and that the phenomenon is linked to various personality and cognitive-style variables. This study aims to investigate whether aspects of family structure (i.e., birth order) and family processes (i.e., family communication patterns) are related to creative facility. Results indicated a significant interaction between birth order and family conversation orientation such that, for first-borns, higher levels of conversation orientation were associated with slower message production. No effects were observed for family conformity orientation. Among the implications of the findings is the need to assess birth order in studies of family communication patterns. 相似文献
996.
In paper conservation ethanol is used as an antifungal agent. However, information on the antifungal efficacy of this alcohol is scarce and often inconsistent. In this study, we clarify if ethanol is effective and safe to use in paper conservation in the short as well as in the long term. None of the tested ethanol concentrations (5–100%) promoted conidia germination, but rather delayed or entirely inhibited it, depending on alcohol concentration and contact time. In a simulation of an interventive treatment of samples colonized by fungi, all the tested ethanolic solutions (30, 70, and 100%) revealed antifungal activity. The best results were obtained with 70% ethanol, showing fungicidal properties on four of the five-tested fungal species (Aspergillus niger, Cladosporium cladosporioides, Penicillium chrysogenum, and Penicillium corylophilum). No deleterious effects of 70% ethanol on the tested paper were observed either in the short or in the long term. 相似文献
997.
Patrick O. Marsh 《Educational technology research and development : ETR & D》1979,27(4):303-318
This article presents a theoretical model for message design proved capable of improving the quality of instruction while
increasing cost effectiveness. Integrating classical rhetoric, information theory, contemporary media criticism, social psychology,
and the psychology of human information processing, the model directs the designer to design a block of time that optimizes
the information load and message complexity within the constraints of the receiver’s abilities and experience, the requirements
of the source, and the capabilities and limitations of the medium. 相似文献
998.
Computercalculationofphasediagramsbeganmorethan30yearsago.Aclearanddetailedreviewoftheearlyworksl'-'lwascontributedbyAnewton-Raphsoniterationtechniqueandthesimplexmethod,andpointedoutthatthemathematicaldeductionsofthelatterarelesscomplicated.Manynsaral'I.… 相似文献
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