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.     

The Perceived Impact of Eight Systemic Factors on Scientific Capital Accumulation

Minerva - In the global academic capitalist race, academics, institutions and countries’ symbolic power results from the accumulation of scientific capital. This paper relies on the...     

Performance of Spanish universities in technology transfer: An empirical analysis

This paper investigates the performance of universities in the transfer of technology using a unique university-level dataset for Spain. The results suggest that universities with established policies and procedures for the management of technology transfer perform better. Universities with large and experienced technology transfer offices (TTOs) generate higher volumes of contract research, but the TTO characteristics appear to matter less for university performance in terms of licensing and creation of spin-offs. Furthermore, universities with a science park perform better than those without, which suggests that the agglomeration of knowledge close to universities has a positive effect on universities’ technology transfer performance.     

Larger strength losses and muscle activation deficits in plantar flexors induced by backward downhill in reference to distance-matched forward uphill treadmill walk

We tested the hypothesis that backward downhill walking (eccentric component) impairs both voluntary activation and muscle contractile properties in the plantar flexors and delays recovery as compared to a gradient and distance-matched uphill walk. Fourteen males performed two 30-min walking exercises (velocity: 1?m/?s; grade: 25%; load: 12% of body weight), one downhill (DW) and one uphill (UP), in a counterbalanced order, separated by 6?weeks. Neuromuscular test sessions were performed before, after, 24-, 48- and 72-h post-exercise, including motor nerve stimulations during brief (5?s) and sustained (1?min) maximal isometric voluntary contractions of the plantar flexors. DW (?18.1?±?11.1%, P?P?=.15), decreased torque production during brief contractions for at least three days post-exercise (P?P?P?=?.024) and DW (?25.6?±?10.3%, P?P?=?.001) was lower in DW than UP. Peak twitch torque and maximum rates of torque development and relaxation were equally reduced after UP and DW (P?P?P?>?.05). Using a direct comparison, the capacity to drive the plantar flexors during sustained contractions remains sub-optimal during the three-day recovery period in response to non-exhaustive, downhill backward walking in reference to an uphill exercise matched for distance covered.     

The coach–athlete relationship: a motivational model

The aim of this paper is to present a motivational model of the coach–athlete relationship that describes how coaches may influence athletes' motivation. In line with cognitive evaluation theory (Deci and Ryan, 1980 Deci EL Ryan RM 1980 The empirical exploration of intrinsic motivational processes In Advances in Experimental Social Psychology, Vol. 13 (edited by L. Berkowitz) pp. 39–80 New York: Academic Press  [Google Scholar], 1985 Deci EL Ryan RM 1985 Intrinsic Motivation and Self-Determination in Human Behavior New York: Plenum Press [Taylor & Francis Online] , [Google Scholar]) and the hierarchical model of intrinsic and extrinsic motivation (Vallerand, 1997 Vallerand RJ 1997 Toward a hierarchical model of intrinsic and extrinsic motivation Advances in Experimental Social Psychology 29 271 360  [Google Scholar], 2000 Vallerand RJ 2000 Deci and Ryan's self-determination theory: a view from the hierarchical model of intrinsic and extrinsic motivation Psychological Inquiry 11 312 318  [Google Scholar]), a motivational sequence is proposed where coaches' personal orientation towards coaching, the context within which they operate, and their perceptions of their athletes' behaviour and motivation influence coaches' behaviours. Also, coaches' behaviours in the form of autonomy-supportive behaviours, provision of structure and involvement have a beneficial impact on athletes' needs for autonomy, competence and relatedness, which, in turn, nurture athletes' intrinsic motivation and self-determined types of extrinsic motivation. Here, we first review coaches' autonomy-supportive behaviours. We then describe the psychological processes through which coaching behaviours have a positive influence on athletes' intrinsic and self-determined extrinsic motivation. Finally, we identify social and personality processes that determine coaching behaviours.     

Sprint mechanical differences at maximal running speed: Effects of performance level

ABSTRACT

As the effect of performance level on sprinting mechanics has not been fully studied, we examined mechanical differences at maximal running speed (MRS) over a straight-line 35 m sprint amongst sprinters of different performance levels. Fifty male track and field sprinters, divided in Slow, Medium and Fast groups (MRS: 7.67 ± 0.27 m?s^?1, 8.44 ± 0.22 m?s^?1, and 9.37 ± 0.41 m?s^?1, respectively) were tested. A high-speed camera (250 Hz) recorded a full stride in the sagittal plane at 30–35 m. MRS was higher (p < 0.05) in Fast vs. Medium (+11.0%) and Slow (+22.1%) as well as in Medium vs. Slow (+10.0%). Twelve, eight and seven out of 21 variables significantly distinguished Fast from Slow, Fast from Medium and Medium from Slow sprinters, respectively. Propulsive phase was signi?cantly shorter in Fast vs. Medium (?17.5%) and Slow (?29.4%) as well as in Medium vs. Slow (?14.4%). Fast sprinters had significantly higher vertical and leg stiffness values than Medium (+44.1% and +18.1%, respectively) and Slow (+25.4% and +22.0%, respectively). MRS at 30–35 m increased with performance level during a 35-m sprint and was achieved through shorter contact time, longer step length, faster step rate, and higher vertical and leg stiffness.     

A motivational model of persistence in science education: A self-determination theory approach

The purpose of this study was to propose and test a motivational model of persistence in science education. The model posits that science teachers’ support of students’ autonomy positively influences students’ self-perceptions of autonomy and competence. These self-perceptions, in turn, have a positive impact on students’ self-determined motivation toward science which leads to their intentions to pursue science education and eventually work in a scientific domain. This model was tested with high school students (n=728). Results from univariate analyses of variance and from structural equation modeling analyses (with LISREL) were found to support the proposed model. In addition, a direct link was obtained between perceptions of competence and intentions to pursue a science education, indicating that higher levels of perceived competence predicted higher levels of persistence intentions. The present findings support Self-Determination Theory and open the way to future research from a motivational approach in this area.     

Acquisition of the concept of teaching and its relationship with theory of mind in French 3- to 6-year olds

Little is known about how and when preschoolers master the concept of teaching, particularly in relation to the acquisition of theory of mind (ToM). We investigated the relationship between the two in children aged 3-6 years old. One hundred and seventeen French preschool pupils answered questions about different teaching situations illustrated in ten stories involving knowledge differences and/or false belief. Four change-of-location ToM stories were also administered. Our results indicate a developmental progression from understanding teaching situations to grasping the notion of knowledge gaps. Moreover, they confirm that ToM seems to be involved in understanding more complex teaching situations.