Complementing subjective with objective data in analysing expertise: A machine-learning approach applied to badminton

ABSTRACT

This study aimed to assess which combination of subjective and empirical data might help to identify the expertise level. A group of 10 expert coaches classified 40 participants in 5 different expertise groups based on the video footage of the rallies. The expertise levels were determined using a typology based on a continuum of 5 conative stages: (1) structural, (2) functional, (3) technical, (4) contextual, and (5) expertise. The video allowed empirical measurement of the duration of the rallies, and tri-axial accelerometers measured the intensity of the player’s involvement. A principal component analysis showed that two dimensions explained 54.9% of the total variance in the data and that conative stage and empirical parameters during rallies (duration, intensity of the game) were correlated with axis 1, whereas duration and acceleration data between rallies were correlated with axis 2. A random forest algorithm showed that among the parameters considered, acceleration, duration of the rallies, and time between rallies could predict conative stages with a prediction accuracy above possibility.

This study suggests that performance analysis benefits from the confrontation of subjective and objective data in order to design training plans according to the expertise level of the participants.     

Religiosity,the headscarf,and education in Turkey: an analysis of 1988 data and current implications

Previous research highlights the continuing relevance of family culture in explaining educational inequalities in Turkey, especially patriarchal beliefs and practices that discourage investment in the education of girls. We extend that research by introducing two much‐debated, but empirically untested, aspects of family culture – parental religiosity and headscarf preferences. An analysis of a nationally representative sample of 15–19 year olds in 1988 shows that while religiosity had no significant effect on educational attainment, children who lived in families whose fathers expected them to wear a headscarf in public had lower educational attainment, especially girls. The large negative headscarf effect suggests that the government ban on headscarves in schools may be an obstacle to eliminating gender inequality in education. The results are discussed in light of recent trends in Turkish society.     

The Relative Efficiency of Departments at a Turkish Engineering College: A Data Envelopment Analysis

In this study, Data Envelopment Analysis is used to measure relative efficiencies of academic departments of an engineering college. Input and output criteria are determined and measured utilizing the academic personnel performance measurement scheme of the College. New measures are developed to compare departments of different disciplines. The discriminating power of the measurement models is improved by restricting criteria weights directly and by using a multiple criteria decision making approach. Sensitivity of the results to exclusion of a criterion and changes in relative importance of the criteria is analyzed. Evaluation of the results jointly by the college administration and the departments is explained for a successful efficiency improvement mechanism.     

Transforming gifts into talents: the DMGT as a developmental theory1

The Differentiated Model of Giftedness and Talent (DMGT) presents the talent development process (P) as the transformation of outstanding natural abilities, or gifts (G), into outstanding systematically developed skills which define expertise, or talent (T) 3 in a particular occupational field. This developmental sequence constitutes the heart of the DMGT. Three types of catalysts help or hinder that process: (a) interpersonal (I) catalysts, like personal traits and self‐management processes; (b) environmental (E) catalysts, like socio‐demographic factors, psychological influences (e.g., from parents, teachers, or peers), or special talent development facilities and programs; and (c) chance (C). The DMGT includes a 5‐level metric‐based (MB) system to operationalize the prevalence of gifted or talented individuals, with a basic ‘top 10 per cent’ threshold for mild giftedness or talent, through successive 10 per cent cuts for moderate, high, exceptional and extreme levels. Complex interactions between the six components are surveyed. The text ends with a proposed answer to a fundamental question: ‘What factor(s) make(s) a difference, on average, between those who emerge among the talented and those who remain average?’     

Effects of slag fineness on durability of mortars

In recent years, the usages of by-products and wastes in industry have become more important. The importance of the sustainable development is also of increasing. The utilizations of wastes, as mineral admixture or fine aggregate, reduce the consumption of the natural resources and improve the durability of concrete. In this study, the effect of the fineness on the high temperature and sulphate resistances of concrete mortar specimens, produced with ground granulated blast-furnace slag (GBFS) replacing cement, is investigated. The compressive and flexural strength test results for all series related to durability effects, exposing temperature and solutions, exposure times for these durability effects, slag content and fineness are discussed. Conse- quently, the optimum slag contents are determined for producing the sulphate and high temperature resistant mortars.