No harmless child labor: The effect of child labor on academic achievement in francophone Western and Central Africa

This study empirically examines the effect of child labor on academic achievement in 10 francophone Western and Central African countries. The data were taken from the Programme d’Analyse des Systèmes Educatifs de la CONFEMEN and comprised characteristics of 25,288 grade six students across 1803 schools. Two-stage least squares analysis highlights that child labor undermines academic achievement regardless of subject, gender, and age. It lowers reading and mathematics scores for both genders and for children under 12 and over 13 years. Child labor therefore hinders human capital accumulation in African countries, and it takes place at the cost of future prosperity.     

Outstanding performances during elite-standard short and middle-distance finals and the hyperandrogenism regulation—A detailed analysis of Caster Semenya’s results

ABSTRACT

Recently, there has been much controversy over the International Association of Athletics Federation (IAAF) regulations regarding eligibility to compete and natural testosterone levels in female athletes. Much interest lies in the analysis of Caster Semenya's extraordinary performance. The objective of this work were, a) Complete an analysis of Caster Semenya's results during the 800m finals and b) search for existing similar performances by other female athletes. We analysed the results of the finals of all IAAF World Championships and Olympic Games from 1984–2016, including the 800m results of the Diamond Leagues 2016–2018. Exponential curves were fit to the data to characterise and predict performance for each event. Caster Semenya's finishing times before her ineligibility to compete and after the suspension of the IAAF hyperandrogenism regulation were found to be 1.24% and 1.49%, respectively, faster than the characteristic performance of the elite-standard in the women’s 800m final. Other female athletes, with finishing times faster than the ones predicted by the characteristic curves were also discovered. The percentage difference in performance between Caster Semenya and the other participants did not reach 3% in the 800m event. No conclusions can be drawn regarding extraordinary results ever performed during the 100m, 200m or 400m finals.     

田径表演赛可行性探析

随着科技水平的发展，电视、多媒体网络等各种传播媒介的迅速发展，体育产业的迅速崛起，人们生活质量的提高、财富的积累，使得人们对体育的诉求也在不断的发生着变化。各种体育赛事逐步融入了表演赛，来扩大本项运动的国际影响力。由于体育明星效应，使得一些体育运动在国内一度掀起过高潮。那么，我们可以借鉴这种市场化的操作方式，从宏观的角度论述田径表演赛，通过明星效应，结合市场管理的方法，提升对田径运动兴趣，加大对田径运动知识的了解、认识，从而起到缓解瓶颈期学校体育中田径常年不受学生青睐的尴尬局面，迎来田径发展新“春天”。     

物理实验操作能力的结构模型初探

中学生物理实验操作能力是物理实验能力的核心部分。本文探讨了物理实验操作能力的定义及其特点 ,并在此基础上构建了物理实验操作能力的结构模型 ,讨论了该模型的特点 ,即整体性、静态性、动态性和自调性。根据物理实验操作能力的结构模型及其特点 ,给出了物理实验操作能力的主要指标     

基于多元线性回归分析的新疆外贸出口对策研究

目前,新疆外贸正处于新旧动能转换的关键时期,培育外贸发展新动力是进入新时代外贸的必然要求,新动力的形成主要需要供给方进行动力重塑和协调发力,在出口方面通过创新驱动、结构调整、制度变革培育供给侧新动力。研究结合供给侧改革对新疆外贸出口依存度进行分析,运用Eviews对与出口相关的因素进行多元线性回归分析,得出结论:一是要素禀赋与出口呈负相关关系;二是新疆GDP对出口有显著的促进作用;三是人民币汇率变动与出口额之间表现为强相关关系;四是外商直接投资与出口较强的相关关系。最后针对多元线性回归的结果,提出相应的外贸出口增长对策。     

远程开放教育成本与效益分析

远程开放教育运用广播电视和计算机网络多媒体技术,使受教育者的数量无限,与国家的“科教兴国”、“全面学习,终身学习”的教育战略相符。但是新技术投资的成本高,其效益的估算难,且如何减少成本,提高效益是有待研讨的课题,需要认真进行分析。一、远程开放教育成本核算的重要意     

The analysis and forecasting of male cycling time trial records established within England and Wales

The format of cycling time trials in England, Wales and Northern Ireland, involves riders competing individually over several fixed race distances of 10–100 miles in length and using time constrained formats of 12 and 24 h in duration. Drawing on data provided by the national governing body that covers the regions of England and Wales, an analysis of six male competition record progressions was undertaken to illustrate its progression. Future forecasts are then projected through use of the Singular Spectrum Analysis technique. This method has not been applied to sport-based time series data before. All six records have seen a progressive improvement and are non-linear in nature. Five records saw their highest level of record change during the 1950–1969 period. Whilst new record frequency generally has reduced since this period, the magnitude of performance improvement has generally increased. The Singular Spectrum Analysis technique successfully provided forecasted projections in the short to medium term with a high level of fit to the time series data.     

A coach’s political use of video-based feedback: a case study in elite-level academy soccer

This paper examines the video-based pedagogical practices of Terry (pseudonym), a head coach of a professional junior academy squad. Data were collected through 6 in-depth, semi-structured interviews and 10 field observations of Terry’s video-based coaching in situ. Three embracing categories were generated from the data. These demonstrated that Terry’s video-based coaching was far from apolitical. Rather, Terry strategically used performance analysis technologies to help fulfil various objectives and outcomes that he understood to be expected of him within the club environment. Kelchtermans’ micropolitical perspective, Callero’s work addressing role and Groom et al.’s grounded theory were primarily utilised to make sense of Terry’s perceptions and actions. The findings point to the value of developing contextually grounded understandings of coaches’ uses of video-based performance analysis technology. Doing so could better prepare coaches for this aspect of their coaching practice.     

The effect of limb dominance on lower limb functional performance – a systematic review

Lower limb dominance (or lateral preference) could potentially effect functional performance. Clinicians are often asked to make judgements as to when a patient has sufficiently “recovered” from an injury, typically using strength and dynamic performance outcome measures. The primary purpose of this study was to systematically review the literature in relation to limb dominance within active adult populations and discuss some limitations to current methods and relate this to current clinical practice. A search of MEDLINE and CINAHL and EMBASE databases and reference lists of those articles identified was performed. Eleven articles were selected for meta-analysis. There was no statistical effect of limb dominance for any of the functional tests: isokinetic quadriceps and hamstring tests, hamstring:quadriceps ratios, single-leg hop for distance, single-leg vertical jump and vertical ground reaction force following a single-leg vertical jump. Pooled symmetry values varied from 94.6% to 99.6% across the tests, above the clinically accepted benchmark of 90% used in clinical practice. Although the results of this study must be used with discretion, asymmetries in the tasks described in this analysis should be viewed as undesirable and remedied accordingly. Further research is needed to quantify asymmetries, particularly in relation to sport-specific contexts.