Competitive balance trends in elite table tennis: the Olympic Games and World Championships 1988-2016

ABSTRACT

Competitive balance is important because it enhances outcome uncertainty and therefore it promotes spectator interest, and encourages government investment in a sport. This article analyses the distribution of gold medals, medals, medal points and top eight points amongst nations in table tennis from 1988 to 2016 at the Olympic Games and the World Championships respectively. A normalised version of the Herfindahl-Hirschman Index and a coefficient of variation are calculated for each nation’s share of these performance indicators. The key findings are that China dominates both events, with successful female players being more dominant than their male counterparts. The competitive balance for gold medals has declined, whilst there is a trend towards improved competitive balance for top eight points for women, suggesting that more teams are featuring in the top eight (but not necessarily the top three) placings. This research has implications for the development of table tennis competitions. Compared to other racket sports, the issue of competitive imbalance in table tennis is particularly thorny, which threatens the long-term development of this sport. Accordingly, some measures are recommended for the International Olympic Committee and the International Table Tennis Federation to propel a more balanced development of international table tennis.     

Self-reported symptoms and risk factors for digital ischaemia among international world-class beach volleyball players

The prevalence of ischaemia-related symptoms is remarkably high among elite indoor volleyball players. Since the exposure to sport-specific demands may be higher in beach volleyball compared to indoor volleyball, the aim of this study was to assess the prevalence of ischaemia-related symptoms and associated risk factors among world-class beach volleyball players. Therefore, a questionnaire survey was performed among beach volleyball players active during the 2013 Grand Slam Beach Volleyball in the Netherlands. In total, 60 of the 128 beach volleyball players (47%) participated: 26 males and 34 females from 17 countries. The self-reported prevalence of cold or blue or pale digits in the dominant hand during or immediately after practice or competition was 38% (n = 23). Two risk factors were independently associated with symptoms of blue or pale digits: more than 14 years playing volleyball (odds ratio (OR) 4.42, 90% confidence interval (90% CI) 1.30–15.07) and sex (female) (OR 4.62, 90% CI 1.15–18.57). In conclusion, the prevalence of symptoms associated with digital ischaemia is high among international world-class beach volleyball players. Female sex and the length of the volleyball career were independently associated with an increased risk of ischaemia-related symptoms. The high prevalence of these seemingly innocuous symptoms and possible associated risk factors warrant regular monitoring since early detection can potentially prevent thromboembolic complications and irreversible tissue damage.     

体育多种评价方法的比较研究

运用相关系数的归一化、标准百分的类比和多类多级判别分析的理论方法，分析于娟推铅球的专项素质对专项成绩影响的重要性大小排序，其排序的评价结果较一致。对这3种方法作为评价手段进行相互比较，相关系数的归一化评价方法较其它2种评价方法合理。     

全民健身与普通高校体育教育管理

本研究运用A.E.SAATY教授提出的AHP层次分析法，对高校体育教育管理目标体系进行系统分析，明确了普通高校体育教育管理体系，建立了判断矩阵，并提出了该管理系统第3层目标的19个构成因素。     

A methodology for the identification of glass panes of different origin in a single stained glass window: Application on two 13th century windows

The chemical composition of 11 glass panes originating from two 13th century non-figurative windows were analyzed by means of Scanning Electron Microscopy–Energy Dispersive X-ray system (SEM-EDX). The windows were discovered in the back-wall of the triforium during the restoration of the choir of the cathedral St. Michael and St. Gudule in Brussels (Belgium). In order to determine if these windows were fabricated with glass of different origin or not, the compositional difference between the panes were compared with the variation in composition as a result of the following causes: (1) compositional fluctuation between panes cut from the same sheet of glass, (2) compositional fluctuation caused when panes are cut from different sheets that were made with the same batch, (3) compositional fluctuation caused when the glass is made from different batches at the same production center, and (4) compositional fluctuation as a result of glass produced at different fabrication centers.     

"审美情调":现代主义艺术魅力的彰显形态

"审美情调"是在对现代主义艺术进行鉴赏时经常会发生的现象.对此,应该重视客体的色彩、形状特征,以及主体的"回忆-联想"机制,因为正是两者之间的互联互动,使审美震撼力转化为艺术魅力,从而让"审美情调"得以缘发出来.     

RIM: A Random Item Mixture Model to Detect Differential Item Functioning

In this paper we present a new methodology for detecting differential item functioning (DIF). We introduce a DIF model, called the random item mixture (RIM), that is based on a Rasch model with random item difficulties (besides the common random person abilities). In addition, a mixture model is assumed for the item difficulties such that the items may belong to one of two classes: a DIF or a non-DIF class. The crucial difference between the DIF class and the non-DIF class is that the item difficulties in the DIF class may differ according to the observed person groups while they are equal across the person groups for the items from the non-DIF class. Statistical inference for the RIM is carried out in a Bayesian framework. The performance of the RIM is evaluated using a simulation study in which it is compared with traditional procedures, like the likelihood ratio test, the Mantel-Haenszel procedure and the standardized p -DIF procedure. In this comparison, the RIM performs better than the other methods. Finally, the usefulness of the model is also demonstrated on a real life data set.     

Patterns of journal publications by staff of the College of Medicine, University of Ibadan, Nigeria, 1961-1980

This study analyzes publishing patterns of the staff of the University of Ibadan College of Medicine, Nigeria, based on a bibliography prepared by the authors. Data-gathering for the bibliography is described. An analysis is made of journals staff published in for the period 1961-1980, focusing on changes in journal order rank, publishing locations, and subject spread. A ranked list of the leading journals for the period 1976-1980 is given, showing the importance of local publishing and pointing to the need for local indexing.     

关于广东省普通高校体育专业招生考试足球项目考试内容、方法及评分标准的研究

采用调查访问、实验法对广东省普通高校体育专业招生考试足球项目考试内容、方法及评分标准进行研究,通过研究．足球非专项考试难度偏低的问题、足球专项考试方法中颠球、绕杆射门项目考试难度偏低以及踢准项目偏难等问题得到解决,从而确立了广东省新的足球专项、非专项考试的各项内容、方法及评分标准,为广东省考试中心组织实施2005年广东省普通高校体育专业招生考试提供了具有实效性和科学性的保证。     

PubMed, Internet Grateful Med, and Ovid: a comparison of three MEDLINE Internet interfaces

Three MEDLINE Internet interfaces are compared: PubMed, Internet Grateful Med, and Ovid MEDLINE. Although these interfaces all search MEDLINE, significant differences exist in terms of their search interfaces, presentation of results, and special features. This paper examines these variations and explores some of the advantages and disadvantages of the three interfaces.