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961.
Attributions in explanations of risk estimates 总被引:1,自引:0,他引:1
Kahlor L Dunwoody S Griffin RJ 《Public understanding of science (Bristol, England)》2002,11(3):243-257
In the spring of 1993, nearly 40 percent of Milwaukee-area residents experienced a nationally publicized outbreak of cryptosporidium, a parasite that infested the metropolitan drinking water supply. Using open-ended survey data gathered from 610 adult residents in the wake of that outbreak, this study looks at factors related to the ways in which people make sense of their quantitative personal risk estimates. The concepts of informal reasoning and attribution aided this endeavor. Analysis of open-ended comments about the risk of getting ill from a waterborne parasite indicated that explanations of personal risk were consistent with predictions made by attribution theory. Good outcomes, which included having remained healthy during the outbreak, were associated with a greater likelihood that respondents would attribute causation to themselves, while one specific bad outcome, having experienced the illness, was associated with a greater likelihood that respondents would attribute causation externally. This study also examined predictors of whether respondents employed probabilistic language in those attributions. Analysis indicated that income was positively related to the use of probability-oriented language, while age and race were negatively related to the use of such language (i.e., persons of color and older individuals were less likely to use such language). 相似文献
962.
This study examined performers' retrospective explanations of the relationship between anxiety symptoms, self-confidence, and performance. Interviews were used to determine how the presence of symptoms and the accompanying directional interpretation affected performance in six elite and six subelite swimmers. Causal networks revealed that perceived control was the moderatingfactor in the directional interpretation of anxiety and not the experience of anxiety symptoms alone. Symptoms perceived to be under control were interpreted to have facilitative consequences for performance; however, symptoms not under control were viewed as debilitative. Increases or decreases in self-confidence wereperceived to improve or lower performance. Findings reveal how cognitive and somatic information was processed, what strategies were adopted, and how this series of events related to performance. 相似文献
963.
This paper examines whether self-controlled feedback schedules enhance learning, because they are more tailored to the performers' needs than externally controlled feedback schedules. Participants practiced a sequential timing task. One group of learners (self-control) was provided with feedback whenever they requested it, whereas another group (yoked) had no influence on the feedback schedule. The self-control group showed learning benefits on a delayed transfer test. Questionnaire results revealed that self-control learners asked for feedback primarily after good trials and yoked learners preferred to receive feedback after good trials. Analyses demonstrated that errors were lower on feedback than no-feedback trials for the self-control group but not for the yoked group. Thus, self-control participants appeared to use a strategy for requesting feedback. This might explain learning advantages of self-controlled practice. 相似文献
964.
Escamilla R Fleisig G Barrentine S Andrews J Moorman C 《Sports biomechanics / International Society of Biomechanics in Sports》2002,1(2):213-228
The purpose of this study was to quantify and compare kinematic, temporal, and kinetic characteristics of American and Korean professional pitchers in order to investigate differences in pitching mechanics, performance, and injury risks among two different cultures and populations of baseball pitchers. Eleven American and eight Korean healthy professional baseball pitchers threw multiple fastball pitches off an indoor throwing mound positioned at regulation distance from home plate. A Motion Analysis three-dimensional automatic digitizing system was used to collect 200 Hz video data from four electronically synchronized cameras. Twenty kinematic, six temporal, and 11 kinetic variables were analyzed at lead foot contact, during the arm cocking and arm acceleration phases, at ball release, and during the arm deceleration phase. A radar gun was used to quantify ball velocity. At lead foot contact, the American pitchers had significantly greater horizontal abduction of the throwing shoulder, while Korean pitchers exhibited significantly greater abduction and external rotation of the throwing shoulder. During arm cocking, the American pitchers displayed significantly greater maximum shoulder external rotation and maximum pelvis angular velocity. At the instant of ball release, the American pitchers had significantly greater forward trunk tilt and ball velocity and significantly less knee flexion, which help explain why the American pitchers had 10% greater ball velocity compared to the Korean pitchers. The American pitchers had significantly greater maximum shoulder internal rotation torque and maximum elbow varus torque during arm cocking, significantly greater elbow flexion torque during arm acceleration, and significantly greater shoulder and elbow proximal forces during arm deceleration. While greater shoulder and elbow forces and torques generated in the American pitchers helped generate greater ball velocity for the American group, these greater kinetics may predispose this group to a higher risk of shoulder and elbow injuries. 相似文献
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经常可以见到一些青少年队员由于缺乏很好的身体条件比赛时不能形成有效的起跳。解决这个问题可以利用一种提高跳跃力量的训练计划,这个计划可从9—11岁少年开始实施。经过研究发现9—11岁少年使用这个计划和手段效果最好,特别是采用向上、向下、向前的越过各种障碍物的跳深练习。这些手段中也包括肌肉力量、耐力、灵活性、协调性的练习。各种方式的练习组合可从下列动作中选择出来进行: 相似文献
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Spink A Yang Y Jansen J Nykanen P Lorence DP Ozmutlu S Ozmutlu HC 《Health information and libraries journal》2004,21(1):44-51
This paper reports findings from an analysis of medical or health queries to different web search engines. We report results: (i). comparing samples of 10000 web queries taken randomly from 1.2 million query logs from the AlltheWeb.com and Excite.com commercial web search engines in 2001 for medical or health queries, (ii). comparing the 2001 findings from Excite and AlltheWeb.com users with results from a previous analysis of medical and health related queries from the Excite Web search engine for 1997 and 1999, and (iii). medical or health advice-seeking queries beginning with the word 'should'. Findings suggest: (i). a small percentage of web queries are medical or health related, (ii). the top five categories of medical or health queries were: general health, weight issues, reproductive health and puberty, pregnancy/obstetrics, and human relationships, and (iii). over time, the medical and health queries may have declined as a proportion of all web queries, as the use of specialized medical/health websites and e-commerce-related queries has increased. Findings provide insights into medical and health-related web querying and suggests some implications for the use of the general web search engines when seeking medical/health information. 相似文献