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采用录像观察法和数理统计法,以2020年东京奥运会60名跆拳道运动员的比赛录像为研究对象,分析、总结世界各地运动员在此次奥运会中应用技战术的特点。认为,若首局得首分,则可增加获胜概率;若首局失首分,则首局往往处于落后状态,此时主动进攻可以增大获胜几率;采用首局得首分战术的运动员带有明显的地域性,欧洲选手使用该战术占比最大为47.36%,非洲选手占比最小为9.09%,并且欧洲选手胜率最高为60.52%,非洲选手胜率最低为9.09%;我国选手孙宏义在使用左开势实战势时技术较为单一,可对此加强训练,郑姝音在使用右闭势实战势时可加强下劈动作的训练。旨在为我国运动员制定科学合理的比赛策略提供数据支持。  相似文献   
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Imbalanced sample distribution is usually the main reason for the performance degradation of machine learning algorithms. Based on this, this study proposes a hybrid framework (RGAN-EL) combining generative adversarial networks and ensemble learning method to improve the classification performance of imbalanced data. Firstly, we propose a training sample selection strategy based on roulette wheel selection method to make GAN pay more attention to the class overlapping area when fitting the sample distribution. Secondly, we design two kinds of generator training loss, and propose a noise sample filtering method to improve the quality of generated samples. Then, minority class samples are oversampled using the improved RGAN to obtain a balanced training sample set. Finally, combined with the ensemble learning strategy, the final training and prediction are carried out. We conducted experiments on 41 real imbalanced data sets using two evaluation indexes: F1-score and AUC. Specifically, we compare RGAN-EL with six typical ensemble learning; RGAN is compared with three typical GAN models. The experimental results show that RGAN-EL is significantly better than the other six ensemble learning methods, and RGAN is greatly improved compared with three classical GAN models.  相似文献   
4.
Meta-analysis is the synthesis of findings from research projects, which enables an estimate of the average or pooled effect across various studies. This study presents findings from the intention to treat analysis for a series of educational evaluations in England using a two-stage meta-analysis with standardised outcome data and individual participant data meta-analyses. The research estimates the overall impact of educational trials on pupils eligible for Free School Meals (FSM) and the attainment gap in literacy and mathematics performance between FSM and non-FSM pupils based on analysis of 88 trials and data from over half a million pupils. For the meta-analyses, frequentist and Bayesian multilevel models were used to estimate the individual and pooled effect size across categories of explanatory variables such as age groups (key stages in England) and aspects of the type of interventions (one-to-one, small group, whole class). Results indicated that the overall impact of interventions on the literacy outcomes of FSM pupils was positive, with a pooled effect size of 0.06 (0.03, 0.08). However, for mathematics, no overall effect on FSM pupils was observed. Analysis of the attainment gap indicated that literacy outcomes for FSM pupils were improved by interventions marginally more than for non-FSM pupils (pooled attainment gap 0.01 (−0.01, 0.04)). The risk of bias assessment showed that estimates were consistent across different methodological approaches. Overall, evidence from this study can be used to identify, test and scale educational interventions in schools to improve educational outcomes for disadvantaged pupils.  相似文献   
5.
It is said that a picture is worth a thousand words, but what about graphs? Although graphs have the potential to bring data to life, numerous studies show that learners struggle with graphical comprehension. Furthermore, many textbook examples on graphs are boring and appear meaningless to students. Students want to know more about something which is interesting, meaningful, and worth knowing, in other words, something relevant. With the outbreak of the novel coronavirus in December 2019, COVID‐19 is dominating the news worldwide, and the internet is flooded with visual presentations about the virus. To make statistics more fascinating and exciting, relevant and real‐world data such as these can be used in the classroom to stimulate the learning of important statistical concepts such as graphs. Curcio's three levels of graphical comprehension were used as a framework in this study, while the importance of developing a global view on distributions was also emphasized.  相似文献   
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人工智能时代为高等教育研究带来本体论、认识论和方法论的变化,从而产生新的高等教育研究范式。该研究范式的旨趣从"数据崇拜"向"数据正义"转变。该研究范式的特征为:研究者的主体性与技术理性结合、计算思维和因果思维结合、研究效率与研究质量并重。该研究范式的价值体现为促进学科建设、解决高等教育实践问题和凝练高等教育思想。为了实现研究范式的旨趣转换,高等教育研究者需要具备范式旨趣转换意识、培养学科情感、研究方法训练、高等基本理论的修养。  相似文献   
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Technical difficulties occasionally lead to missing item scores and hence to incomplete data on computerized tests. It is not straightforward to report scores to the examinees whose data are incomplete due to technical difficulties. Such reporting essentially involves imputation of missing scores. In this paper, a simulation study based on data from three educational tests is used to compare the performances of six approaches for imputation of missing scores. One of the approaches, based on data mining, is the first application of its kind to the problem of imputation of missing data. The approach based on data mining and a multiple imputation approach based on chained equations led to the most accurate imputation of missing scores, and hence to most accurate score reporting. A simple approach based on linear regression performed the next best overall. Several recommendations are made regarding the reporting of scores to examinees with incomplete data.  相似文献   
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大数据时代最重要的转变就是研究范式的转变,而数据密集型科学范式(e Science)正是大数据时代高职院校思想政治教育研究与实践的全新范式。在大数据时代背景下,高职院校思想政治教育工作要实现数据密集型科学研究新范式的重大转变,那就必须注重夯实思想政治教育队伍的大数据素养,完善伦理道德与制度建设并重的数据安全机制,打破数据壁垒全面提升共享数据质量,构建铸魂育人的麦肯锡分析模型与立德树人的用户行为路径分析模型,最终实现精准思政、精准育人的目标。  相似文献   
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计算机软件蕴含大量工作信息,有效挖掘软件数据信息之间的内在关联是信息时代对软件应用的潜在要求。针对经典Apriori算法挖掘数据效率低、复杂度高的问题,提出一种改进Apriori算法用于挖掘计算机软件数据的关联规则。为计算机软件算法设置双重支持度阈值,即频繁项集与非频繁项集支持度阈值,快速获得强关联的频繁项集;在此基础上基于映射规则重构事务数据库,压缩数据库规模,减少算法的剪枝操作,降低计算机软件数据关联规则挖掘复杂度。以人力资源类计算机软件数据为例展开关联分析测试,结果显示,该算法挖掘的关联信息与人力资源实际管理情况一致,相比经典Apriori算法其效率有所提升。  相似文献   
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“互联网+”技术的快速发展和广泛应用,要求党员教育培训模式实现迭代升级、与时俱进,这既是巨大的挑战又孕育着难得的创新党员教育培训模式的机遇。受新冠肺炎疫情影响,杭州市直机关党员教育培训工作乘势转变理念、手段和方式,在改进传统的线下集中教育培训模式的同时,引入在线直播技术,实现了机关党员教育培训线下集中教育培训模式与“线上直播+党员教育培训”模式的有机衔接、优势互补、立体推进,有效地提高了机关党员教育培训效率与效果。打造以“互联网+”为内涵的“线上直播+党员教育培训”模式金名牌,需要以5G通信、云计算、大数据技术为支撑,不断开拓线上直播教学新形态,精准配套采取对策举措。  相似文献   
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