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排序方式: 共有804条查询结果,搜索用时 78 毫秒
771.
Who reads literature? Using national survey data, Nicholas Zill and Marianne Winglee analyze the audience for quality fiction, poetry, and drama—its size, potential for growth, demographic composition, and reading preferences. They discuss the factors that affect literary participation and investigate the mechanisms of these effects. They then examine the policy implications of their findings and suggest several ways that publishers, book-sellers, and librarians can use the survey results to increase the reading of quality fiction, poetry, and drama. 相似文献
772.
Stefan C. Dombrowski A. Alexander Beaujean Ryan J. McGill Nicholas F. Benson W. Joel Schneider 《Structural equation modeling》2013,20(6):847-860
Exploratory bifactor analysis (EBFA) represents a methodological advancement for implementing a bifactor model in exploratory factor analysis (EFA). However, little is known about how to properly employ the procedure. The current rotation criteria available for EBFA make it more likely to “get stuck” in local minima, contributing to possible group factor collapse, than more traditional EFA rotations. Thus, getting a proper solution is a more complex and involved process than typical EFA and may require a sensitivity analysis. This article examines EBFA through a sensitivity analysis and subsequent simulation of parameters thought to contribute to group factor collapse. Results support the use of sensitivity analysis, as the problematic variable was shown to greatly increase the likelihood of factor collapse. The hypothesis that estimation start values contribute to factor collapse was not supported. Accompanying R syntax for all analyses are provided to facilitate reproducibility. 相似文献
773.
Search engines and other text retrieval systems use high-performance inverted indexes to provide efficient text query evaluation. Algorithms for fast query evaluation and index construction are well-known, but relatively little has been published concerning update. In this paper, we experimentally evaluate the two main alternative strategies for index maintenance in the presence of insertions, with the constraint that inverted lists remain contiguous on disk for fast query evaluation. The in-place and re-merge strategies are benchmarked against the baseline of a complete re-build. Our experiments with large volumes of web data show that re-merge is the fastest approach if large buffers are available, but that even a simple implementation of in-place update is suitable when the rate of insertion is low or memory buffer size is limited. We also show that with careful design of aspects of implementation such as free-space management, in-place update can be improved by around an order of magnitude over a naïve implementation. 相似文献
774.
Florence R. Sullivan Claire E. Hamilton Danielle A. Allessio Rachel J. Boit Alexandra D. Deschamps Tony Sindelar German E. Vargas Ramos Anthony Randall Nicholas Wilson Yan Zhu 《Educational technology research and development : ETR & D》2011,59(5):619-644
In this paper we report the results of a study which investigated the affordances of multi-user virtual environments (MUVEs)
for collaborative learning from a design perspective. Utilizing a mixed methods approach, we conducted a comparative study
of the effect of varying representational and interactional design features on a collaborative design activity in three online
synchronous environments. We compared environments featuring multiple modes of interaction (MUVEs), shared representations
(text chat and 2D still images) and text-only features. Sixty-one students enrolled in an undergraduate course on Child Development
participated in the study. Participants were asked to design a theoretically-based, developmentally appropriate, preschool
classroom setting. Students were randomly assigned to one of three online learning environments that provided varying levels
of representation and interaction. Significant differences in collaborative problem solving interactions were found. Participants
in the shared representations + text condition evidenced stronger learning outcomes as regards substantive discussion and
integration of child development concepts; while participants in the MUVE condition reported the most enjoyment with the experience.
These findings are explained by the concepts of representational guidance, representational bias, educational affordances
and interface design metaphors. Suggestions for the design of MUVEs for collaborative learning are provided. 相似文献
775.
David Nicholas Anthony Watkinson Cherifa Boukacem‐Zeghmouri Blanca Rodríguez‐Bravo Jie Xu Abdullah Abrizah Marzena
wigo David Clark Eti Herman 《Learned Publishing》2019,32(3):237-247
This article provides the final results of a 3‐year study that sought to discover whether early career researchers (ECRs) were the harbingers of change with respect to scholarly communications. Over a hundred science and social science ECRs from seven countries, spanning three continents, were depth‐interviewed annually for 3 years (2016–2018) about their attitudes and behaviours with respect to 23 scholarly issues and activities (aspects). In order to provide an accessible overarching assessment of an extremely large and complex dataset, the interview data were categorized according to the strength and direction of change exhibited and the trends and points of interest raised. Results show that all ECRs have changed in one way or another, and a small minority has changed greatly in both attitude and practice and that collaboration and research impact are the scholarly aspects where most changes have occurred, and the greatest cause of change is not so much new technology as a change of jobs. 相似文献
776.
Hyojong Sohn Kelly Acosta Mary T. Brownell Nicholas A. Gage Eilish Tompson Carolyn Pudvah 《Learning disabilities research & practice》2023,38(2):85-103
This meta-analysis synthesized 97 effect sizes extracted from 37 intervention studies for students with reading difficulties (RDs) in Grades 6 to 12 published between 1982 and 2021 to identify the overall impact of reading interventions and the moderating effects of intervention characteristics and study design characteristics. Random-effects robust variance estimation (RVE) was used to account for dependencies within studies. Overall, interventions designed to improve reading comprehension outcomes for adolescents with RDs were effective (g = 0.63). Meta-regression analyses identified several significant moderators that were associated with intervention efficacy, such as text content, duration of intervention, agent of intervention, status of student, type of dependent measure, and study quality. We provide study limitations as well as implications for research and practice. 相似文献
777.
778.
Nicholas C. Burbules 《Educational theory》2014,64(4):317-331
779.
A long stream of academic literature has established that public funding towards research and development matters for economic growth because it relates to increases in innovation, productivity and the like. The impact of public funding on the creation of new firms has received less attention in this literature despite theoretical constructs that support such association. In the present paper we study whether indeed there is a relationship between public research funds and local firm births in the context of the U.S. biotechnology industry. In doing so, we introduce a number of changes that strengthen the robustness of our findings when compared with existing literature. These changes include a direct measure of research expenditures and a considerably lengthier longitudinal dataset which allows us to capture a structural relationship and not a chance event. We empirically demonstrate that increases in the level of research funding from the National Institutes of Health towards biotechnology associate with increases in the number of biotechnology firm births at the Metropolitan Statistical Area level. Further, we reveal that public funds towards established firms associate with local firm births considerably more strongly when compared with funds towards universities and research institutes/hospitals. We conclude the paper with academic and policy implications of the present work that highlight the complexity of factors that underlie the creation of local firms in high technology industries. 相似文献
780.
Alison Alcock Adam Hunter Nicholas Brown 《Sports biomechanics / International Society of Biomechanics in Sports》2013,12(2):129-140
The ability to determine a specific location on a football (soccer) pitch from television footage would provide a cost-effective method of obtaining competition-specific information on many professional and international teams. This study presents the accuracy and reliability of a new method of calculating ball location from simulated television coverage and known pitch markings. The coordinates of 99 markers of known location on a football pitch were digitized from video. An intersection point was determined from the equations of two lines that form pitch markings and the relationship from this point to other known pitch coordinates was calculated using a curve-fitting based method. Average error between known and reconstructed measures was 0.21 m for pitch width and 0.11 m for pitch length from a view simulating television coverage. Inter- and intra-rater reliability analyses showed researchers could consistently reconstruct pitch locations to within less than half a metre. The accuracy and reliability of this method will be sufficient for most practical uses in an applied sport environment, although the level of accuracy required will depend on the specific application. This method could be applied to other sports to determine specific locations on a pitch or court or to improve current competition analysis systems. 相似文献