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991.
Derwin K. C. Chan Alfred Sing Yeung Lee Duncan J. Macfarlane Martin S. Hagger Kyra Hamilton 《Journal of sports sciences》2020,38(14):1666-1673
ABSTRACT Two studies were employed to test the reliability and validity of the Swimming Competence Questionnaire (SCQ) among primary school children. Study 1 was a cross-sectional survey in 4959 primary school children. Study 2 was a pre-post-test quasi-experiment among 1609 primary school children who underwent a 20-lesson learn-to-swim programme. In Study 1, exploratory structural equation modelling revealed excellent goodness-of-fit and scale reliability for a two-factor model comprising distance and skill factors, which supported the construct and convergent validity. SCQ scores were significantly and positively correlated with swimming outcomes (i.e., self-efficacy, intention, swimming frequency), which supported SCQ’s concurrent and criterion validity. Average variance extracted for the SCQ factors exceeded cut-off criteria supporting discriminant validity. In Study 2, pre-test SCQ scores correlated significantly and positively with the SCQ scores, self-efficacy, intention, and swimming frequency at post-test, which supported SCQ’s test-retest reliability and predictive validity. Positive intraclass correlation between SCQ scores and coach ratings at post-test provided evidence for SCQ’s inter-rater reliability. SCQ scores significantly improved at post-test, which supported SCQ’s ecological validity. In conclusion, findings indicate that the SCQ is a valid and reliable measure to assess primary school children’s swimming competence, in terms of swimming distance and basic water survival skills. 相似文献
992.
The research examined whether youth (6–17 years old) who were referred for treatment due to sexual, physical, or both types of abuse presented with distinct profiles of PTSD DSM-IV-TR symptom clusters. When examining data for the 749 youth participants, five PTSD symptom cluster profiles were identified with each profile representing approximately 20% of the youth. The five profiles were also differentiated with respect to being referred for physical or sexual abuse, age, parental ratings of internalizing symptoms, and self-reported depression. The youth referred for treatment in the aftermath of child sexual, physical, or both sexual and physical abuse presented with different profiles of PTSD symptom clusters thereby suggesting a need for individualized tailoring of evidenced-based treatments. Two cognitive behavioral approaches, designed for traumatized children and either their nonoffending or offending parents, were described for treating youth with the distinct PTSD profiles. 相似文献
993.
Katherine A. MacDonald Patricia K. Hrynchak Marlee M. Spafford 《Journal of the Medical Library Association》2014,102(3):210-215
North American optometry and ophthalmology faculty members and vision science librarians were surveyed online (14% response rate) about teaching evidence-based practice (EBP). Similar to studies of other health care programs, all five EBP steps (Ask, Acquire, Appraise, Apply, Assess) were taught to varying degrees. Optometry and ophthalmology EBP educators may want to place further emphasis on (1) the Apply and Assess steps, (2) faculty- and student-generated questions and self-assessment in clinical settings, (3) online teaching strategies, (4) programmatic integration of EBP learning objectives, and (5) collaboration between faculty members and librarians. 相似文献
994.
995.
996.
Document length is widely recognized as an important factor for adjusting retrieval systems. Many models tend to favor the
retrieval of either short or long documents and, thus, a length-based correction needs to be applied for avoiding any length
bias. In Language Modeling for Information Retrieval, smoothing methods are applied to move probability mass from document
terms to unseen words, which is often dependant upon document length. In this article, we perform an in-depth study of this
behavior, characterized by the document length retrieval trends, of three popular smoothing methods across a number of factors,
and its impact on the length of documents retrieved and retrieval performance. First, we theoretically analyze the Jelinek–Mercer,
Dirichlet prior and two-stage smoothing strategies and, then, conduct an empirical analysis. In our analysis we show how Dirichlet
prior smoothing caters for document length more appropriately than Jelinek–Mercer smoothing which leads to its superior retrieval
performance. In a follow up analysis, we posit that length-based priors can be used to offset any bias in the length retrieval
trends stemming from the retrieval formula derived by the smoothing technique. We show that the performance of Jelinek–Mercer
smoothing can be significantly improved by using such a prior, which provides a natural and simple alternative to decouple
the query and document modeling roles of smoothing. With the analysis of retrieval behavior conducted in this article, it
is possible to understand why the Dirichlet Prior smoothing performs better than the Jelinek–Mercer, and why the performance
of the Jelinek–Mercer method is improved by including a length-based prior.
相似文献
Leif AzzopardiEmail: |
997.
Panagiotis Symeonidis Alexandros Nanopoulos Apostolos N. Papadopoulos Yannis Manolopoulos 《Information Retrieval》2008,11(1):51-75
Collaborative Filtering (CF) Systems have been studied extensively for more than a decade to confront the “information overload”
problem. Nearest-neighbor CF is based either on similarities between users or between items, to form a neighborhood of users
or items, respectively. Recent research has tried to combine the two aforementioned approaches to improve effectiveness. Traditional
clustering approaches (k-means or hierarchical clustering) has been also used to speed up the recommendation process. In this paper, we use biclustering
to disclose this duality between users and items, by grouping them in both dimensions simultaneously. We propose a novel nearest-biclusters
algorithm, which uses a new similarity measure that achieves partial matching of users’ preferences. We apply nearest-biclusters
in combination with two different types of biclustering algorithms—Bimax and xMotif—for constant and coherent biclustering,
respectively. Extensive performance evaluation results in three real-life data sets are provided, which show that the proposed
method improves substantially the performance of the CF process.
相似文献
Yannis ManolopoulosEmail: |
998.
A compressed full-text self-index for a text T, of size u, is a data structure used to search for patterns P, of size m, in T, that requires reduced space, i.e. space that depends on the empirical entropy (H
k
or H
0) of T, and is, furthermore, able to reproduce any substring of T. In this paper we present a new compressed self-index able to locate the occurrences of P in O((m + occ)log u) time, where occ is the number of occurrences. The fundamental improvement over previous LZ78 based indexes is the reduction of the search
time dependency on m from O(m
2) to O(m). To achieve this result we point out the main obstacle to linear time algorithms based on LZ78 data compression and expose
and explore the nature of a recurrent structure in LZ-indexes, the suffix tree. We show that our method is very competitive in practice by comparing it against other state of the art compressed
indexes.
相似文献
Arlindo L. OliveiraEmail: |
999.
Twose C Swartz P Bunker E Roderer NK Oliver KB 《Health information and libraries journal》2008,25(1):13-22
PURPOSE: To increase understanding of the information needs and use of public health practitioners. SETTING: From June 2005 to May 2006, the library offered a course in public health information resources to eighteen practitioners in two counties, access to the library's licensed electronic resources through a tailored web portal, and consulting services. EVALUATION METHOD: We combined usage statistics from the web portal, self-report and observational data collected during training and shadowing of participants. CONCLUSIONS: The data from this project indicate that usage of licensed information resources and services is infrequent but broad ranging. A few users register at the high end of the usage range, but one use of one high quality article can have a significant impact on policy decisions. Time and competing responsibilities often constrain the retrieval and use of resources for evidence-based decision making and an informationist or power-user model may be more appropriate than training all practitioners to integrate searching into their workflow. This study indicates (i) that evidence-based public health practice requires seamless and broadly based information access; and (ii) that the currently existing patchwork does not support the level of use or take into account the time constraints of information needs for public health practice. 相似文献
1000.
Deurenberg R Vlayen J Guillo S Oliver TK Fervers B Burgers J;SEARCH Group 《Health information and libraries journal》2008,25(1):23-30
BACKGROUND: Effective literature searching is particularly important for clinical practice guideline development. Sophisticated searching and filtering mechanisms are needed to help ensure that all relevant research is reviewed. PURPOSE: To assess the methods used for the selection of evidence for guideline development by evidence-based guideline development organizations. METHODS: A semistructured questionnaire assessing the databases, search filters and evaluation methods used for literature retrieval was distributed to eight major organizations involved in evidence-based guideline development. RESULTS: All of the organizations used search filters as part of guideline development. The medline database was the primary source accessed for literature retrieval. The OVID or SilverPlatter interfaces were used in preference to the freely accessed PubMed interface. The Cochrane Library, embase, cinahl and psycinfo databases were also frequently used by the organizations. All organizations reported the intention to improve and validate their filters for finding literature specifically relevant for guidelines. DISCUSSION: In the first international survey of its kind, eight major guideline development organizations indicated a strong interest in identifying, improving and standardizing search filters to improve guideline development. It is to be hoped that this will result in the standardization of, and open access to, search filters, an improvement in literature searching outcomes and greater collaboration among guideline development organizations. 相似文献