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921.
922.
Rafael B. Pereira Alexandre Plastino Bianca Zadrozny Luiz H.C. Merschmann 《Information processing & management》2018,54(3):359-369
In many important application domains, such as text categorization, scene classification, biomolecular analysis and medical diagnosis, examples are naturally associated with more than one class label, giving rise to multi-label classification problems. This fact has led, in recent years, to a substantial amount of research in multi-label classification. In order to evaluate and compare multi-label classifiers, researchers have adapted evaluation measures from the single-label paradigm, like Precision and Recall; and also have developed many different measures specifically for the multi-label paradigm, like Hamming Loss and Subset Accuracy. However, these evaluation measures have been used arbitrarily in multi-label classification experiments, without an objective analysis of correlation or bias. This can lead to misleading conclusions, as the experimental results may appear to favor a specific behavior depending on the subset of measures chosen. Also, as different papers in the area currently employ distinct subsets of measures, it is difficult to compare results across papers. In this work, we provide a thorough analysis of multi-label evaluation measures, and we give concrete suggestions for researchers to make an informed decision when choosing evaluation measures for multi-label classification. 相似文献
923.
AbstractHow should contemporary societies promote physical activity in nature and preservation of the natural environment? Outdoor life occupies a central and contested position on this question in the Nordic countries. In Norway, a 1957 Act of Parliament took a major step by guaranteeing free public access to both public and private uncultivated land. This article explores the media debate that raged in 2008–2009, when the national government proposed new legislation intended to promote outdoor life, sport, nature experience and urban forest preservation around Oslo, Norway’s capital. Applying narrative and discourse methodologies, this case study reveals how the media debate evolved from an initial cacophony of voices into a schism between advocates of nature preservation and advocates of sport. The controversy explored here is increasingly relevant throughout all of Europe: how to encourage urban active living, sustainable recreation and democratic citizenship that embody distinct social practices, identities, emotional bonds and symbolic meaning. 相似文献
924.
Matthew B. Rhudy Scott B. Dreisbach Matthew D. Moran Marissa J. Ruggiero Praveen Veerabhadrappa 《Journal of sports sciences》2020,38(5):503-510
ABSTRACTAccelerometer cut points are an important consideration for distinguishing the intensity of activity into categories such as moderate and vigorous. It is well-established in the literature that these cut points depend on a variety of factors, including age group, device, and wear location. The Actigraph GT9X is a newer model accelerometer that is used for physical activity research, but existing cut points for this device are limited since it is a newer device. Furthermore, there is not existing data on cut points for the GT9X at the ankle or foot locations, which offers some potential benefit for activities that do not involve arm and/or core motion. A total of N = 44 adults completed a four-stage treadmill protocol while wearing Actigraph GT9X sensors at four different locations: foot, ankle, wrist, and hip. Metabolic Equivalent of Task (MET) levels assessed by indirect calorimetry along with Receiver Operating Characteristic (ROC) curves were used to establish cut points for moderate and vigorous intensity for each wear location of the GT9X. Area under the ROC curves indicated high discrimination accuracy for each case. 相似文献
925.
926.
Christopher M Young Wei Luo Paul B Gastin Daniel B Dwyer 《Journal of sports sciences》2020,38(6):676-681
ABSTRACTThe aim of this study was to assess if tactical and technical performance indicators (PIs) could be used in combination to model match outcomes in Australian Football (AF). A database of 101 technical PIs and 14 tactical PIs from every match in the 2009–2016 Australian Football League (AFL) seasons was merged. Two outcome measures Win-loss and Score margin were used as dependent variables. The top 45 ranked technical and tactical PIs from a feature selection process were used to model match outcome using decision tree and Generalised Linear Models (GLMs). Of the top 45 selected features, this included seven tactical PIs. The Win-loss-based Decision tree model achieved a classification accuracy of 89.0% and GLM 93.2%. A Score margin-based GLM achieved a root mean squared error (RMSE) of 6.9 points. A combined approach to the classification of match outcomes provided no improvement in model accuracy compared with previous literature. However, this study has established the relative importance of technical and tactical measures of performance in relation to successful team performance in AF. 相似文献
927.
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
928.
929.
A new vision of school counseling asserts that counselors must address all children and must orient counseling services toward the primary mission of schools: to educate young people and to support their healthy development. Two universities that are working to prepare new vision school counselors have changed their recruitment and selection procedures to attract increased numbers of candidates who can be optimally trained to fulfill the requirements of this vision. The authors describe criteria and procedures used to select graduate students who have the greatest promise of becoming leaders, advocates, and change agents in schools to promote student learning and achievement. 相似文献
930.
The ability of 8-month-old infants to localize an event from a new direction of facing was tested in a square and a circular room with and without a landmark. Subjects were trained to anticipate the site from 2 directions of facing and then tested in a new direction of facing. The number of trials to a criterion of learning, the number of subjects looking first at the event site after reorientation, and the time spent in doing so were recorded. Taken together, the results show that at 8 months ability to identify the site of an event after reorientation is based on the spatial relationship between the event and environmental features. The latter include features associated with room shape as well as a landmark at the site of the event. 相似文献