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1.
Nowadays assuring that search and recommendation systems are fair and do not apply discrimination among any kind of population has become of paramount importance. This is also highlighted by some of the sustainable development goals proposed by the United Nations. Those systems typically rely on machine learning algorithms that solve the classification task. Although the problem of fairness has been widely addressed in binary classification, unfortunately, the fairness of multi-class classification problem needs to be further investigated lacking well-established solutions. For the aforementioned reasons, in this paper, we present the Debiaser for Multiple Variables (DEMV), an approach able to mitigate unbalanced groups bias (i.e., bias caused by an unequal distribution of instances in the population) in both binary and multi-class classification problems with multiple sensitive variables. The proposed method is compared, under several conditions, with a set of well-established baselines using different categories of classifiers. At first we conduct a specific study to understand which is the best generation strategies and their impact on DEMV’s ability to improve fairness. Then, we evaluate our method on a heterogeneous set of datasets and we show how it overcomes the established algorithms of the literature in the multi-class classification setting and in the binary classification setting when more than two sensitive variables are involved. Finally, based on the conducted experiments, we discuss strengths and weaknesses of our method and of the other baselines.  相似文献   
2.
Collaborations in funded teams are essential for understanding funded research and funding policies, although of high interest, are still not fully understood. This study aims to investigate directed collaboration patterns from the perspective of the knowledge flow, which is measured based on the academic age. To this end, we proposed a project-based team identification approach, which gives particular attention to funded teams. The method is applicable to other funding systems. Based on identified scientific teams, we detected recurring and significant subgraph patterns, known as network motifs, and under-represented patterns, known as anti-motifs. We found commonly occurred motifs and anti-motifs are remarkably characterized by different structures matching certain functions in knowledge exchanges. Collaboration patterns represented by motifs favor hierarchical structures, supporting intensive interactions across academic generations. Anti-motifs are more likely to show chain-like structures, hindering potentially various knowledge activities, and are thus seldom found in real collaboration networks. These findings provide new insights into the understanding of funded collaborations and also the funding system. Meanwhile, our findings are helpful for researchers, the public and policymakers to gain knowledge on research(ers) evolution, particularly in terms of primordial collaboration patterns.  相似文献   
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4.
According to the goal orientation model, students’ achievement goals and beliefs are interrelated. Within this framework, research and theory have so far assumed that achievement goals are associated with students’ beliefs of causes of success, the latter representing students’ subjective beliefs about the factors contributing to success at school. So far, this line of research has been restricted to a few cross-sectional studies. We examined the temporal relations between achievement goals (mastery, performance-approach, and performance-avoidance goals) and students’ beliefs of causes of success, the latter operationalized by asking the students to rate the subjective importance of diligence, effort, and ability for school success. Achievement goals and beliefs of causes of success were measured twice with a time lag of one school year with a sample of N = 2044 German secondary school students. Cross-lagged panel models were estimated to examine the temporal relations between achievement goals and beliefs of causes of success while controlling for students’ secondary school track, socio-economic status, and Grade Point Average. Former mastery goals were found to be positively related to later importance ratings of diligence for school success; former performance-approach goals were found to be positively related to later importance ratings of ability. Boys and girls were found to display similar relations among constructs but they showed differential mean levels on both the achievement goal constructs and the beliefs of causes of success. Implications for research on achievement goals and practice using intervention approaches are discussed.  相似文献   
5.
Using PISA and PIAAC data from twelve OECD countries, we examine the gap in cognitive skills among immigrants and natives and evaluate how those differences have evolved over time. We also consider how demographics, family background and school quality explain the development of cognitive skills of young people with immigrant backgrounds. The results show, first, that some convergence in skills occurs between second-generation immigrants and natives over time. Second, demographics, family background and school quality variables all contribute to the achievement gaps across different groups.  相似文献   
6.
随着信息技术日新月异、行业形态不断改变、新业态源源不断出现,社会对人才培养也随之提出更高的要求。在开放教育中,综合实践教学虽然处在战略性地位,但是在学习者专业技能培养中,往往只偏重于理论教育,实践技能教育存在流于形式、学习内容陈旧、实践资源缺失等问题,导致人才培养与实际岗位需求脱节。为了适应开放教育的发展趋势,结合当前开放教育综合实践教学中存在的实施不足、教学方式单一和实践基地弱化等问题,提出开放教育综合实践教学模式应以“学分银行”理念为基础,对综合实践教学进行行之有效的改革,以提升其教学质量和有效性。  相似文献   
7.
微时代大学生思政课自主学习享有网络信息带来的便捷,同时也面临网络裹挟的一些干扰。克服这些干扰还存在一些主要障碍,需要在提高学生意识形态的鉴别力、增强自主学习环境的塑造力、提高教师自身网络教育的驾驭力和提升网络学习的保障力等方面下功夫。  相似文献   
8.
本文采用文献资料法,视频分析法,专家访谈法,比较分析法和数理统计法等研究方法。对2018年世锦赛中日集体花球啦啦操成套创编进行比较研究,包括三大技术技巧难度(跳步、转体、柔韧与平衡)、连接难度(集体类、技巧类、层次等)、托举与配合(托举、配合)、基本手位等。力图对这些进行定量对比分析、探究,分析中日两国成套动作差异等,以期为国内成套花球舞蹈啦啦队练习的创作和编写提供参考。  相似文献   
9.
时至今日,武术仍未能很好地进入校园,其原因何在,如何从柔道、跆拳道、空手道的成功现代化和国际化当中寻求启发,成为紧迫论题。主要运用文献资料法,基于对学校武术历史、现状的反思和日韩武技现代化的启示,对我国学校武术的根本问题和根本方略做出探讨。研究认为,学校武术开展的现状不能实现中华民族赋予它的文化使命,日韩武技现代化的经验可为我们提供启示——将传统意义上的搏杀武技改造为一项现代文明搏击项目,该项目需满足几个趋势保证安全文明化、保持技击本质性、具有游戏趣味性、彰显民族独特性。在此基础上,做出武术以太极推手形式进入校园的提案。  相似文献   
10.
In two experimentally-based and longitudinally-designed studies, secondary-level PE teachers were randomly assigned to participate or not in a new intervention to help them learn all of the following: support autonomy, provide structure, and provide structure in an autonomy-supportive way. In Study 1, teachers who participated in the intervention showed longitudinal gains in all five hypothesized teacher benefits (e.g., teaching efficacy, job satisfaction). In Study 2, students of teachers who participated in the intervention showed longitudinal gains in all four hypothesized student benefits (e.g., classroom engagement, skill development). Overall, teachers and students benefited after teachers provided structure in an autonomy-supportive way.  相似文献   
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