Using web-based training to enhance perceptual-cognitive skills in complex dynamic offside events

In association football, the difficulty in making offside decisions depends on both perceptual and cognitive processes. Therefore, the objectives of the present study were to enhance the decision-making skills of assistant referees by further developing their ability to (1) time slice the incoming information flow into series of isolated time frames during an ongoing offside situation and (2) use this information to mentally read off the spatial positions of the key-role players. Training (n = 10) and control groups (n = 10) were exposed to a pre- and post-test, consisting of an offside decision-making and frame recognition test. In the latter, assistant referees were asked to indicate which of five photos best represented the spatial position of the defender and attacker at the moment of the pass. Only the training group received 12 web-based offside training sessions. First, the training group improved in mentally freezing, holding and scanning the mental picture of the offside situation in short-term memory from pre- to post-test, as evidenced by an increased recognition accuracy. Second, the improvement in recognition accuracy resulted in enhanced performance on the offside decision-making task. The benefits of web-based training are highlighted.     

Estimation of ‘real’ numerosities in elementary school children

Groups of mathematically strong and weak second-, fourth- and sixth-graders were individually confronted with numerosities smaller and larger than 100 embedded in one-, two- or three-dimensional realistic contexts. While one third of these contexts were totally unstructured (e.g., an irregular piece of land jumbled up with 72 cars), another third had a clear structure (e.g., a 16x4 rectangular parking lot completely filled with 64 cars), and a last third had a “semi-structure” (e.g., the same 16x4 parking lot but with a number of cars missing). Besides analyzing the effects of different task and subject variables on pupils’ accuracy and response-time data, the study involved and analysis of their estimation strategies, with an emphasis on multiplicative strategies that profited by some of the tasks’ geometrical (semi-)structure. It was found that many children actually made use of such strategies, that using these strategies did however not always led to accurate estimations, and that their frequency and efficiency increased with age.     

Conceptualizing, investigating, and enhancing adaptive expertise in elementary mathematics education

Some years ago, Hatano differentiated between routine and adaptive expertise and made a strong plea for the development and implementation of learning environments that aim at the latter type of expertise and not just the former. In this contribution we reflect on one aspect of adaptivity, namely the adaptive use of solution strategies in elementary school arithmetic. In the first part of this article we give some conceptual and methodological reflections on the adaptivity issue. More specifically, we critically review definitions and operationalisations of strategy adaptivity that only take into account task and subject characteristics and we argue for a concept and an approach that also involve the sociocultural context. The second part comprises some educational considerations with respect to the questions why, when, for whom, and how to strive for adaptive expertise in elementary mathematics education.     

Validity and reliability of a new field test (Carminatti's test) for soccer players compared with laboratory-based measures

The aim of this study was to assess the validity (Study 1) and reliability (Study 2) of a novel intermittent running test (Carminatti's test) for physiological assessment of soccer players. In Study 1, 28 players performed Carminatti's test, a repeated sprint ability test, and an intermittent treadmill test. In Study 2, 24 players performed Carminatti's test twice within 72 h to determine test-retest reliability. Carminatti's test required the participants to complete repeated bouts of 5 × 12 s shuttle running at progressively faster speeds until volitional exhaustion. The 12 s bouts were separated by 6 s recovery periods, making each stage 90 s in duration. The initial running distance was set at 15 m and was increased by 1 m at each stage (90 s). The repeated sprint ability test required the participants to perform 7 × 34.2 m maximal effort sprints separated by 25 s recovery. During the intermittent treadmill test, the initial velocity of 9.0 km · h(-1) was increased by 1.2 km · h(-1) every 3 min until volitional exhaustion. No significant difference (P > 0.05) was observed between Carminatti's test peak running velocity and speed at VO(2max) (v-VO(2max)). Peak running velocity in Carminatti's test was strongly correlated with v-VO(2max) (r = 0.74, P < 0.01), and highly associated with velocity at the onset of blood lactate accumulation (r = 0.63, P < 0.01). Mean sprint time was strongly associated with peak running velocity in Carminatti's test (r = -0.71, P < 0.01). The intraclass correlation was 0.94 with a coefficient of variation of 1.4%. In conclusion, Carminatti's test appears to be avalid and reliable measure of physical fitness and of the ability to perform intermittent high-intensity exercise in soccer players.     

Plasmaaustausch und Immunadsorption

Ohne Zusammenfassung     

Associations of Number Line Estimation With Mathematical Competence: A Meta‐analysis

The number line estimation task is widely used to investigate mathematical learning and development. The present meta‐analysis statistically synthesized the extensive evidence on the correlation between number line estimation and broader mathematical competence. Averaged over 263 effect sizes with 10,576 participants with sample mean ages from 4 to 14 years, this correlation was r = .443. The correlation increased with age, mainly because it was higher for fractions than for whole numbers. The correlation remained stable across a wide range of task variants and mathematical competence measures (i.e., counting, arithmetic, school achievement). These findings demonstrate that the task is a robust tool for diagnosing and predicting broader mathematical competence and should be further investigated in developmental and experimental training studies.     

Parental involvement and adolescent school achievement: the mediational role of self-regulated learning

Both parental involvement and self-regulated learning are important predictors of students’ study success. However, previous research on self-regulated learning has focused instead on the school environment and has not focused on the home situation. In particular, investigations into the role of parents in self-regulated learning when children enter middle school have been limited. The present study examined the relationship among students’ perceptions of parental involvement, their self-regulated learning and school achievement in the first year of middle school. Survey data from 5939 Flemish students were processed using mediation analyses and revealed that students’ perceptions of parental involvement in school work was associated with students’ self-regulated learning and their school achievement. Moreover, how students perceived parental involvement was associated with students’ achievement through the self-regulated learning factors. These results underpin the importance of parents in education at the middle-school age. Schools should be aware of this and enhance parents’ educational involvement and the stimulation of self-regulated learning in the home environment.

     

Toward a systematic framework for research on dominant designs, technological innovations, and industrial change

The concept of a dominant design has taken on a quasi-paradigmatic status in analyses of the link between technological and industrial dynamics. A review of the empirical literature reveals a variety of interpretations about some aspects of the phenomenon such as its underlying causal mechanisms and its level of analysis. To stimulate further progress in empirical research on dominant designs, we advocate a standardization of terminology by conceptualizing products as complex artifacts that evolve in the form of a nested hierarchy of technology cycles. Such a nested complex system perspective provides both unambiguous definitions of dominant designs (stable core components that can be stable interfaces) and inclusion of multiple levels of analysis (system, subsystems, components). We introduce the concept of an operational principle and offer a systematic definition of core and peripheral subsystems based on the concept of pleiotropy. We also discuss how the proposed terminological standardization can stimulate cumulative research on dominant designs.     

Multidimensional performance characteristics and standard of performance in talented youth field hockey players: a longitudinal study

To identify performance characteristics that could help predict future elite field hockey players, we measured the anthropometric, physiological, technical, tactical, and psychological characteristics of 30 elite and 35 sub-elite youth players at the end of three consecutive seasons. The mean age of the players at the end of the first season was 14.2 years (s = 1.1). Repeated-measures analyses of covariance, with standard of performance and measurement occasion as factors and age as a covariate, showed that the elite players fared better than the sub-elite players on technical and tactical variables. Female elite youth players also scored better on interval endurance capacity, motivation, and confidence. Future elite players appear to have excellent tactical skills by the age of 14. They also have good specific technical skills and develop these together with interval endurance capacity better than sub-elite youth players in the subsequent 2 years. To verify our conclusions, we will be tracking these players into adulthood.     

Relation between multidimensional performance characteristics and level of performance in talented youth field hockey players

To determine the relationship between multidimensional performance characteristics and level of performance in talented youth field hockey players, elite youth players (n = 38, mean age 13.2 years, s = 1.26) were compared with sub-elite youth players (n = 88, mean age 14.2 years, s = 1.26) on anthropometric, physiological, technical, tactical and psychological characteristics. Multivariate analyses with performance level and gender as factors, and age as the covariate, showed that the elite youth players scored better than the sub-elite youth players on technical (dribble performance in a peak and repeated shuttle run), tactical (general tactics; tactics for possession and non-possession of the ball) and psychological variables (motivation) (P < 0.05). The most discriminating variables were tactics for possession of the ball, motivation and performance in a slalom dribble. Age discriminated between the two groups, indicating that the elite youth players were younger than the sub-elite players. In the guidance of young talented players to the top as well as in the detection of talented players, more attention has to be paid to tactical qualities, motivation and specific technical skills.