高校志愿者参与大型节事的动机研究——以2009世界集邮展览为例     

张洁 《昆明大学学报》2010,2(2):81-87

高校志愿者参与大型节事的动机主要有理想奉献动机、自我提高动机、归属动机、走出常规动机、回报社会动机、社会责任动机、功利利益动机、消磨时光动机。其中,志愿者所处的年级及是否隶属于某个志愿者组织对志愿者参与动机没有影响,专业差别会导致志愿者在理想奉献动机上有显著差异,性别差异导致志愿者在理想奉献动机和自我提高动机上有显著差异,志愿者是否参与过其他志愿活动或是否有过志愿服务经历会导致志愿者在理想奉献动机、自我提高动机、走出常规动机、归属动机、回报社会动机、消磨时间动机上存在显著性差异。  相似文献   

测量误差二次多项式回归模型随机误差方差的相合估计     

黄业文 《重庆职业技术学院学报》2009,18(3):100-101

在实际应用中,测量误差二次多项式回归模型随机误差方差σc^2的值经常是不能确定的,这给模型进一步处理带来麻烦,我们从收集的样本（Xt,Yt）,t=1,2,…,n,定义一个函数来估计一的值,进而得到一的相合估计值。  相似文献   

非线性模型中无信息方差和协方差分量Bayes估计   总被引：1，自引：1，他引：0  

闫同新 《福建工程学院学报》2009,7(4)

采用Bayes方法从无先验信息出发,得到了非线性模型中方差和协方差分量的估计(包含相关系数),最后通过实例解算,结果表明:非线性模型中方差和协方差分量的估计,与ρ的理论值-0.5偏差不大,当没有先验信息时,该方法是可行的.  相似文献   

Time course of recovery of vertical jump height and heart rate versus running speed after a 90-km foot race     

Alan M Nevill  Roger L Holder  Arthur D Stewart 《Journal of sports sciences》2013,31(7):645-650

It is well known that sport and exercise play an important role in stimulating site-specific bone mineral density (BMD). However, what is less well understood is how these benefits dissipate throughout the body. Hence, the aim of the present study was to compare the BMD (recorded at nine sites throughout the skeleton) of 106 male athletes (from nine sports) with that of 15 male non-exercising age-matched controls. Given that BMD is known to increase with body mass and peak with age, multivariate and univariate analyses of covariance were performed to compare the BMD of the nine sports groups with controls (at all sites) using body mass and age as covariates. Our results confirmed a greater adjusted BMD in the arms of the upper-body athletes, the right arm of racket players and the legs of runners (compared with controls), supporting the site-specific nature (i.e. specific to the externally loaded site) of the bone remodelling response (all P?<0.01). However, evidence that bone mass acquisition is not just site-specific comes from the results of the rugby players, strength athletes, triathletes and racket players. The rugby players' adjusted BMD was the greatest of all sports groups and greater than controls at all nine sites (all P?<0.01), with differences ranging from 8% greater in the left arm to 21% in the lumbar spine. Similarly, the strength athletes' adjusted BMD was superior to that of controls at all sites (P?<0.05) except the legs. The adjusted BMD of the triathletes was significantly greater than that of the controls in both the arms and the legs as well as the thoracic and lumbar spine. The racket players not only had significantly greater right arm BMD compared with the controls but also a greater BMD of the lumbar spine, the pelvis and legs. In contrast, the low-strain, low-impact activities of keep-fit, cycling and rowing failed to benefit BMD compared with the age-matched controls. These results suggest that sporting activities involving high impact, physical contact and/or rotational forces or strains are likely to convey significant benefits not only to the loaded sites, but also to other unloaded peripheral and axial sites throughout the skeleton.  相似文献   

世界原油价格波动对我国农产品价格影响实证分析   总被引：2，自引：1，他引：1  

卢福财  何文章 《软科学》2013,27(4)

以2002年1月～2011年12月的世界原油期货价格和我国农产品玉米、小麦、大豆以及猪肉价格的月度数据时间序列为例,运用单位根检验、协整检验、脉冲响应函数以及方差分解等时间序列技术,对世界原油价格波动与我国农产品价格变化关系进行实证分析。结果发现,我国农产品价格影响因素最大的是其自身的供需关系,而世界原油价格波动对我国农产品价格影响的大小不均衡,对玉米、小麦影响较大,而对猪肉价格影响不显著。  相似文献   

Variability in Measurement of Swimming Forces     

Rod Havriluk 《Research quarterly for exercise and sport》2013,84(2):32-39

An analysis was conducted to identify sources of true and error variance in measuring swimming drag force to draw valid conclusions about performance factor effects. Passive drag studies were grouped according to methodological differences: tow line in pool, tow line in flume, and carriage in tow tank. Active drag studies were grouped according to the theoretical basis: added and/or subtracted drag (AAS), added drag with equal power assumption (AAE), and no added drag (ANA). Data from 36 studies were examined using frequency distributions and meta-analytic procedures. It was concluded that two active methods (AAE and ANA) had sources of systematic error and that one active method (AAS) measured an effect that was different from that measured by passive methods. Consistency in drag coefficient (Cd) values across all three passive methods made it possible to determine the effects of performance factors.  相似文献   

体育专业学生显性身体素质课程实验研究——以四川民族学院体教10级本科为例     

蒲西安  游敏 《体育科技文献通报》2013,(10):48-49,60

用T检验、卡方检验和回归分析,对在体育专业学科教学中,采用每星期加开一次课（90分钟）的身体素质显性课程教学和没有加开身体素质显性课程教学进行一年的教学实验研究,其结果表明：（对照组）没有开设身体素质显性课程的学生100米、铅球和立定跳远成绩均不如（实验组）每星期加开一次身体素质显性课程教学的班级,实验组经过一年的实验后各项身体素质均有大幅度提高,实验组和对照组的身体素质水平呈非常显著性差异。此研究为今后体育专业课程设置和教学改革提供理论依据。  相似文献   

Factorial Validity and Reliability of the Curricular Goals in Physical Education Questionnaire     

Nelli Lyyra  Esko Leskinen  Pilvikki Heikinaro-Johansson 《Measurement in physical education and exercise science》2013,17(2):69-79

This study aimed to examine the validity and reliability of an instrument designed to measure student perceptions of curricular goals in physical education, the Curricular Goals in Physical Education Questionnaire. Participants were 879 Finnish students from grades 7 to 9 (412 girls, 467 boys; mean age 13.81). An exploratory factor analysis was performed on Sample 1 (n = 287), revealing a four-factor solution and suggesting that factor structure be cross-validated with confirmatory factor analysis in Sample 2 (n = 592). Confirmatory factor analysis demonstrated an acceptable fit and supported the four-factor model. Tests for gender invariance supported configural, metric, and scalar invariance. Analyses of factor mean differences indicated that girls attributed more importance than boys to physical education’s health-related goals, social and emotional learning, and motor skill development. This study confirmed the validity of the Curricular Goals in Physical Education Questionnaire to assess student perspectives on curricular goals across gender. In order to improve factor structure the authors suggest the addition of an item measuring skill acquisition to future versions of the instrument.  相似文献   

超几何分布的期望和方差的一种新求法     

马松林 《巢湖学院学报》2006,8(3):139-140

本文介绍如何运用概率母函数来求超几何分布的期望和方差  相似文献   

柔性制造与职业技术教育的对比分析     

陈斌  杨敏  魏庆曜 《成都教育学院学报》2005,19(1):24-26,30

文章在分析柔性制造基本特征的基础之上,归纳提出了柔性制造的柔性特征.通过对柔性制造与职业技术教育的本质比较,论述了二者的可比性并概括了二者的类比要素.最后,文章对二者的各种柔性特征进行了比较分析,得出了柔性制造与现代职业技术教育的相似性结论,为进一步引入柔性制造系统理论来构建基于柔性制造的职业技术教育模式奠定了理论基础.  相似文献