18131. |
- Segaard, Jacob, et al.
(författare)
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Subjective analysis and objective characterization of adaptive bitrate videos
- 2016
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Ingår i: Electronic Imaging. - : The Society for Imaging Science and Technology. - 9781510827943 ; , s. 55-63
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Konferensbidrag (refereegranskat)abstract
- The HTTP Adaptive Streaming (HAS) technology allows video service providers to improve the network utilization and thereby increasing the end-users' Quality of Experience (QoE). This has made HAS a widely used approach for audiovisual delivery There are several previous studies aiming to identify the factors influencing on subjective QoE of adaptation events. However, adapting the video quality typically lasts m a time scale much longer than what current standardized subjective testing methods are designed for. thus making the full matrix design of the experiment on an event level hard to achieve. In this study, we investigated the overall subjective QoE of 6 minutes long video sequences containing different sequential adaptation events. This was compared to a dataset from our previous work performed to evaluate the individual adaptation events. We could then derive a relationship between the overall mean opinion score (MOS) and the MOS from shorter sequences. The aforementioned empirical dataset has proven to be very challenging in terms of video quality assessment test design, thus deriving a conclusive outcome about the influence of different parameters have been difficult. The second contribution of this study is considering how objective characterizations of adapted videos can improve the understanding of the subjective ratings.
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18132. |
- Segerberg, Tim
(författare)
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The Personalization of Electoral Participation? : The Relationship Between Trait Evaluations of Presidential Candidates and Turnout Decisions in American Presidential Elections 1980–2020
- 2024
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Ingår i: Political Behavior. - : Springer Nature. - 0190-9320 .- 1573-6687.
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Tidskriftsartikel (refereegranskat)abstract
- The personalization thesis claims that leaders’ influence over voters has increased. While research consistently shows that candidates influence party choice, we know little about their effects on the prior decision to turn out in elections. This article represents the first study to examine the relationship between candidate trait evaluations and turnout decisions in the American context and the first longitudinal study of the phenomenon. The study utilizes ANES data to test three hypotheses drawn from theories on electoral participation and personalized politics in U.S. presidential elections between 1980 and 2020. The results show that while trait evaluations of Republican candidates consistently affect turnout, perceptions of Democratic candidates’ competence mobilize voters in specific elections. Moreover, individual polarization promotes turnout, particularly among partisan dealigned voters with different perceptions of the candidates’ competence. The results indicate a personalization of electoral participation that can benefit civic engagement and democratic quality.
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18133. |
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18134. |
- Segerholm, Christina, 1956-, et al.
(författare)
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Changing evaluation systems – changing expectations? The case of Swedish higher education
- 2014
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Ingår i: Symposium Governing by Expectations: School Inspection and Evaluation across Europe and Beyond.
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Konferensbidrag (refereegranskat)abstract
- As a part of the ‘audit society’ (Power 1997), the idea of systematic evaluations is strongly promoted in contemporary education policy (Ozga et al. 2011). Higher education is not an exception and European policy like the Bologna declaration and the development of common quality indicators are just a few examples. Looking at the national arena, this paper aims at exploring the relation between evaluation systems in Swedish higher education and governing from 1993 and onwards. Theoretically we recognize the dynamic relationship underling both institutional reproduction and change (Mahoney & Thelen 2010). Evaluation systems may change gradually or more dramatically and these dynamics hold implications for governing and for how we can understand expectations of what is to count as, for instance, as ‘good quality’ Hopmann et al. 2007). Official policy texts are used and a qualitative content analysis (Bergström & Boréus 2005) is performed, guided by questions like: What is evaluated? Why? By whom? How? With what consequences? The results suggest that the governing potential in the evaluation systems in higher education in the Swedish case partly relies on the shifts themselves. By constantly changing the systems, expectations are also changed and form one important part of the work of governing.
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18135. |
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18136. |
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18137. |
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18138. |
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18139. |
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18140. |
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