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941.
What a difference a day makes: Estimating daily learning gains during kindergarten and first grade using a natural experiment 总被引:1,自引:0,他引:1
Knowing whether time spent in formal schooling increases student achievement, and by how much, is important for policymakers interested in determining efficient use of resources. Using the ECLS-K, we exploit quasi-randomness in the timing of assessment dates to examine this question. Conservative estimates suggest a year of school results in gains of about one standard deviation above normal developmental gains in both reading and math test scores. The results are statistically significant and extremely robust to specification choice, supporting quasi-randomness of test dates. Estimates of skill accumulation due to formal schooling do not vary based on socioeconomic characteristics. 相似文献
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An analytical framework for the cross-country comparison of higher education governance 总被引:2,自引:0,他引:2
In this article we provide an integrated framework for the analysis of higher education governance which allows us to more systematically trace the changes that European higher education systems are currently undergoing. We argue that, despite highly insightful previous analyses, there is a need for more specific empirically observable indicators of policy change and inertia. We therefore propose a systematic classification of empirical indicators of higher education governance. To do so, we look at three historically entrenched and still highly relevant European models of higher education??academic self-governance, the state-centered model and the market-oriented model. Based on these broader overarching models which reflect the tensions between the state, market and academia, we develop three ideal-types that take internal university governance as well as the role of the state and external stakeholders into account. Against this background, we derive empirical indicators with regard to the institutional balance of power, financial governance, personnel autonomy and substantive matters. Our analytical contribution shall enable scholars, and in particular political and social scientists, to trace ongoing patterns of change and convergence as well as persistence and inertia in higher education governance arrangements. 相似文献
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Rosa Maria Bottino 《Education and Information Technologies》2007,12(2):93-105
The idea of using the internet as a platform to mediate social interactions and learning at different levels has progressively
affirming itself, and this has given rise to a huge number of spontaneous and planned collectives, which are often described
as on-line learning networks. On-line learning networks create value through the combination of content and people’s knowledge.
They can vary widely in the strength and permanence of their connections and the resources necessary to maintain them. Aspects
of both a pragmatic and social nature need to be carefully considered in the process of initiation of on-line learning communities.
This paper considers learning networks from the perspective of the potential they offer to the strengthening of relationships
among institutions, groups, and people sharing a common interest in computer-enhanced learning. Some case studies are analysed
and an analytical framework is sketched out to guide observations and to provide a lens through which case studies can be
interpreted. The final goal is to delineate a reference for identifying strong and weak elements in virtual networks and to
examine under what conditions they are succeeding. In addition, some possible scenarios for on-line networks are delineated
along two main lines: the organisation and structure of the network and its level of establishment.
相似文献
Rosa Maria BottinoEmail: |
948.
ABSTRACT The restoration of the Roman building of the third-fourth century CE called Minerva Medica, in Rome, highlighted a problem concerning the choice of the color of the bricks for integration. Current conservation practice in Italy favours a restoration that as much as possible is consistent with the original but leaves some visible differences to a careful observer. Color measurement is usually performed using portable spectrocolorimeters that provide the reflectance spectrum and also colorimetric parameters such as L* a* b*, h* L* C*, RGB, etc. In other sectors, such as for olive oils, for wines, and also for the colors of commercial products, sensory panels are used to provide results of difference/similarity and are known to be similar to observations made by consumers. In this study, data from a top quality spectrocolorimeter and from a sensory panel are compared. Twenty non-professional people were involved in the comparison between seven restoration bricks and three ancient Roman bricks from the studied site. Observations took place in a room with controlled lighting, and each observer filled out a sensory card using about 2000 known comparison colors. Comparison of the results was carried out with graphic methods and by means of cluster analysis. The results show that the sensory panel could be a useful alternative to colorimetry, while cluster analysis allowed a significant response to questions posed by conservation professionals, and was confirmed by other graphic-statistical methods. 相似文献
949.
Ghinea R Ugarte-Alvan L Yebra A Pecho OE Paravina RD Perez Mdel M 《Journal of Zhejiang University. Science. B》2011,12(7):552-562
This study deals with the influence of surface roughness on the color of resin composites. Ten resin composites (microfilled,
hybrid, and microhybrid) were each polished with 500-grit, 1 200-grit, 2 000-grit, and 4 000-grit SiC papers. The roughness
parameter (R
a) was measured using a Plμ confocal microscope, and field-emission scanning electron microscope (Fe-SEM) images were used
to investigate filler morphology. Color was measured using a spectroradiometer and a D65 standard illuminant (geometry diffuse/0°
specular component excluded (SCE) mode). Surface roughness decreased with grit number and was not influenced by filler size
or size distribution. A significant influence of R
a on lightness (L*) was found. Lightness increased with decreases in roughness, except for specimens that underwent polishing procedure 4 (PP4;
500-grit, 1 200-grit, 2 000-grit, and 4 000-grit SiC papers consecutively). Generally, it was found that surface roughness
influenced the color of resin composites. The composites that underwent PP1 (500-grit SiC paper) exhibited significant differences
in chroma (C*), hue (h°), and lightness (L*) compared to composites that underwent PP3 (500-grit, 1 200-grit, and 2 000-grit SiC papers consecutively) and PP4. Color
difference (ΔE*) between the polishing procedures was within acceptability thresholds in dentistry. 相似文献
950.
Gavin Boyce Angela Greenwood Amy Haworth Jacky Hodgson Chris Jones Gary Marsh Maria Mawson Rosa Sadler 《The Journal of Academic Librarianship》2019,45(5):102046
Over the course of 2018 the University of Sheffield Library conducted a series of interviews and workshops with stakeholders as part of a strategic project to reflect on the value of the university library in the 21st century. Using a mixed methodology, participants were asked to reflect upon the future Higher Education (HE) environment for the university and, for academic participants, their discipline. In this context participants were also asked to reflect upon the future value of the University Library in a series of questions designed to elicit value statements using a tool which the project group have called the ‘Wheel of Value’. The resulting reflections upon the future environment have been grouped into four categories reflecting the drivers for change; Digitalisation, Student Experience, Diversification and Collaboration recognizing that there is considerable overlap and interconnection between these. The reflections on the future value of the library are presented by Wheel of Value higher order categorization. This approach proved useful in eliciting responses from participants in the face of recognized difficulty in getting beyond current views of the library and the approach is recommended to other universities looking to carry out a similar project. The results of this research will be used to inform the development of a view of the library for the purpose of engaging with our university community and key partners. 相似文献