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101.
Stephen D. Herrmann Kristin J. Heumann Cheryl A. Der Ananian Barbara E. Ainsworth 《Measurement in physical education and exercise science》2013,17(3):221-235
There is limited published validity and reliability evidence to support using the Global Physical Activity Questionnaire. Two studies were conducted to evaluate validity and reliability evidence for the Global Physical Activity Questionnaire. In Study 1: 69 adults completed the Global Physical Activity Questionnaire (three months apart; n?=?54), International Physical Activity Questionnaire, fitness and anthropometric measures. All participants wore a pedometer and 53 participants wore an accelerometer for seven days at baseline. In Study 2, 16 adults completed the Global Physical Activity Questionnaire 10 days apart. Global Physical Activity Questionnaire moderate and vigorous minutes were correlated with the accelerometer moderate (r?=?0.28) and vigorous (r?=?0.48) physical activity. The Global Physical Activity Questionnaire and International Physical Activity Questionnaire were related for sedentary behaviors (r?=?0.51), moderate-to-vigorous (r?=?0.48) and vigorous (r?=?0.63) PA. Global Physical Activity Questionnaire moderate-to-vigorous physical activity was associated with percent fat (r =??0.32), estimated VO2 max (r?=?0.26), and step count (r?=?0.39). The Global Physical Activity Questionnaire demonstrated graded differences across categories for step count, body mass index, waist circumference, percent fat, fitness, and accelerometer measured activity. Short-term test–retest reliability (10 days) ranged from 0.83 to 0.96 while long-term reliability (three months) was 0.53 to 0.83. These data provide low-to-moderate validity and generally acceptable reliability evidence for the Global Physical Activity Questionnaire. 相似文献
102.
Part of the promise of electronic government (e-government) is its ability to transform the delivery of information services and products from government to users. E-government allows federal agencies to supplement and even supplant private sector roles intermediating between government agencies and users, creating unintended consequences in terms of policy, theory, and practice. The problem is called “channel conflict” in the marketing literature, and the typical response is called distribution channel management (DCM). After reviewing the literatures of e-government, information policy, and DCM, the paper explores differing DCM philosophies of two federal agencies: the Internal Revenue Service and the U.S. Census Bureau. An examination of these two DCM programs provides insights on how federal agencies may be able to manage their various channels for e-government offerings despite tensions in the current legal and policy context. The paper concludes by using DCM literature to help frame options for dealing with these tensions. 相似文献
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105.
Learning Algorithms for Keyphrase Extraction 总被引:20,自引:0,他引:20
Peter D. Turney 《Information Retrieval》2000,2(4):303-336
Many academic journals ask their authors to provide a list of about five to fifteen keywords, to appear on the first page of each article. Since these key words are often phrases of two or more words, we prefer to call them keyphrases. There is a wide variety of tasks for which keyphrases are useful, as we discuss in this paper. We approach the problem of automatically extracting keyphrases from text as a supervised learning task. We treat a document as a set of phrases, which the learning algorithm must learn to classify as positive or negative examples of keyphrases. Our first set of experiments applies the C4.5 decision tree induction algorithm to this learning task. We evaluate the performance of nine different configurations of C4.5. The second set of experiments applies the GenEx algorithm to the task. We developed the GenEx algorithm specifically for automatically extracting keyphrases from text. The experimental results support the claim that a custom-designed algorithm (GenEx), incorporating specialized procedural domain knowledge, can generate better keyphrases than a general-purpose algorithm (C4.5). Subjective human evaluation of the keyphrases generated by GenEx suggests that about 80% of the keyphrases are acceptable to human readers. This level of performance should be satisfactory for a wide variety of applications. 相似文献
106.
Logan SW Scrabis-Fletcher K Modlesky C Getchell N 《Research quarterly for exercise and sport》2011,82(3):442-448
The purpose of this study was to examine the relationship between motor proficiency and body mass index (B/MI) in preschool children. Thirty-eight children ages 4-6 years had their BMI calculated and were assessed using the Movement Assessment Battery for Children-2 (MABC-2; Henderson, Sugden, & Barnett, 2007). These data were analyzed in two ways. The correlation between BMI and MABC-2 percentile ranks was calculated. Next, the groups were subdivided based on BMI status (high, M = 85.5; medium, M = 49.8; low, M = 10.8), and compared using t tests to determine if differences existed in MABC-2 percentile ranks. No significant relationship existed between MABC-2 and BMI percentile ranks (r = -.237). However significant differences in MABC-2 percentile ranks existed between high and low (p = .042), and high and medium (p = .043) groups. These results suggest that preschool children classified as overweight or obese may have lower motor proficiency than their normal weight and under weight peers. This study indicates there is a direct relationship between motor proficiency and BMI in the preschool population. 相似文献
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108.
This study examined the incidence, severity, and timing of gastrointestinal (GI) symptoms in finishers and non-finishers of the 161-km Western States Endurance Run. A total of 272 runners (71.0% of starters) completed a post-race questionnaire that assessed the incidence and severity (none = 0, mild = 1, moderate = 2, severe = 3, very severe = 4) of 12 upper (reflux/heartburn, belching, stomach bloating, stomach cramps/pain, nausea, vomiting) and lower (intestinal cramps/pain, flatulence, side ache/stitch, urge to defecate, loose stool/diarrhoea, intestinal bleeding/bloody faeces) GI symptoms experienced during each of four race segments. GI symptoms were experienced by most runners (96.0%). Flatulence (65.9% frequency, mean value 1.0, s = 0.6 severity), belching (61.3% frequency, mean value 1.0, s = 0.6 severity), and nausea (60.3% frequency, mean value 1.0, s = 0.7 severity) were the most common symptoms. Among race finishers, 43.9% reported that GI symptoms affected their race performance, with nausea being the most common symptom (86.0%). Among race non-finishers, 35.6% reported that GI symptoms were a reason for dropping out of the race, with nausea being the most common symptom (90.5%). For both finishers and non-finishers, nausea was greatest during the most challenging and hottest part of the race. GI symptoms are very common during ultramarathon running, and in particular, nausea is the most common complaint for finishers and non-finishers. 相似文献
109.
Jeffrey Calderon Rena Subotnik Steven Knotek Kristin Rayhack Jason Gorgia 《Journal of educational and psychological consultation》2013,23(4):347-367
The American Psychological Association's Center for Gifted Education Policy (CGEP) reviewed the literature on current talent development models and conducted research on music conservatory students, high IQ students, and science-talented students as sources for a new developmental model called scholarly productivity/artistry (SP/A).The third stage of the SP/A model, where psychosocial dimensions of talent development play the most prominent role, serves as the framework for adolescent summer programs offered by CGEP. The authors argue that the psychosocial dimensions of talent development make gifted children and adolescents a promising population for consulting psychology. 相似文献
110.
Effects of an Attachment‐Based Intervention on Child Protective Services–Referred Mothers' Event‐Related Potentials to Children's Emotions 下载免费PDF全文
This study examined the neurobiology of maternal sensitivity to children's emotions among mothers involved with Child Protective Services (CPS) and low‐risk comparison mothers (Mage = 31.6 years). CPS‐referred mothers participated in the Attachment and Biobehavioral Catch‐up (ABC) intervention or a control intervention. Mothers' event‐related potentials (ERPs) were measured while they categorized images of children with crying, laughing, and neutral expressions. CPS‐referred ABC mothers (n = 19) and low‐risk comparison mothers (n = 30) showed a larger enhancement of ERP responses for emotional faces relative to neutral faces than CPS‐referred control mothers (n = 21). Additionally, the magnitude of ERP responses to emotional faces was associated with observed maternal sensitivity. Findings add to the understanding of the neurobiology of deficits in parenting and suggest that these deficits are changeable through a parenting intervention. 相似文献