Machine learning for human learners: opportunities,issues, tensions and threats

Educational technology research and development - Machine learning systems are infiltrating our lives and are beginning to become important in our education systems. This article, developed from a...     

Translation,cross-cultural adaptation,validity, reliability and stability of the Dutch Injury - Psychological Readiness to Return to Sport (I-PRRS-NL) scale

The Injury Psychological Readiness to Return to Sport (I-PRRS) scale measures the psychological readiness of injured athletes to resume sports participation. The aim of this study was to translate and culturally adapt the I-PRRS scale into Dutch (I-PRRS-NL) and assess its validity, reliability, and stability in patients after anterior cruciate ligament reconstruction (ACLR). The original I-PRRS was translated and culturally adapted from English into Dutch, and tested for clinimetric quality. To assess concurrent validity, 150 patients completed the I-PRRS-NL scale and five questionnaires measuring related constructs 3–16 months after ACLR. All predefined hypotheses regarding correlations between the I-PRRS-NL scale and these questionnaires were confirmed, indicating good concurrent validity. For test-retest reliability, 107 patients completed the I-PRRS-NL scale again two weeks later. The I-PRRS-NL scale showed good internal consistency (Cronbach’s alpha 0.94) and test-retest reliability (ICC 0.89). Standard error of measurement was 4.2 and smallest detectable change was 11.6. No systematic bias between test and retest was found. As the scale appears unstable at item level, only the total score should be used. Overall, the I-PRRS-NL scale showed sufficient validity and reliability to assess the psychological readiness to resume sports among Dutch-speaking patients after ACLR.     

A multi-sensor system for automatic analysis of classical cross-country skiing techniques

Commercial systems utilizing data from inertial measurement units (IMUs) to analyse movement patterns have not yet been adapted to monitor daily training in cross-country (XC) skiing. The main purposes of this study are to investigate: (1) the feasibility and potential of a multi-sensor system consisting of a heart rate sensor, global navigation satellite systems (GNSSs) data and seven IMUs placed at multiple locations on the body for outdoor XC skiing, and (2) the validity of employing hard decision rules based on the correlation between arms and legs for detecting sub-techniques in classical XC skiing. All sensor data were synchronously sampled and synchronized with GNSS data from a commercially available sports watch while XC skiing on varying tracks, from amateur skiers and world-class athletes. An algorithm based on the correlation of the angular velocity of arms and legs was developed to detect the three main classic sub-techniques, diagonal, double poling with a kick and double poling. Other sub-techniques were classified as miscellaneous (0–20%). The system is shown to work well outdoors on snow during different conditions, and the implemented algorithm was validated by video analyses to detect the three sub-techniques with a sensitivity of 99–100%. This study is the first to detect and link sub-techniques in XC skiing to GNSS data, thereby associating the detection and distribution of sub-techniques to different terrains. Such information gives insight into the technical and tactical aspects of skiers’ daily training and competitions, thereby providing a tool for coaches and athletes.     

Uneducating South Africa: The failure to address the 1910–1993 legacy

This paper analyses various data on the South African schooling system since 1910. The data collected for the study cover a wide range of education indicators, from pupil enrolments, pupil teacher ratios, real expenditure (aggregate and per capita), matriculation pass rates, to some indicators of the quality of matriculation passes. The authors provide an indication of both inputs into and outputs of the educational system. In broad terms, the data indicate that from an educational perspective South Africa followed a modernisation trajectory that, although it drew ever larger numbers of pupils into the schooling system, was partial, distorted and fundamentally dysfunctional. The educational process was strongly affected by racial factors. To the extent that education is an important determinant of long run growth performance of economies, this implies that South Africa's educational policies were inimical to its long run growth.     

Risk factors for musculoskeletal injuries in elite junior tennis players: a systematic review

The objective was to systematically review the literature on risk factors and prevention programs for musculoskeletal injuries among tennis players. PubmedMedline, Embase, CINAHL, Cochrane, SportDiscus were searched up to February 2017. Experts in clinical and epidemiological medicine were contacted to obtain additional studies.

For risk factors, prospective cohort studies (n > 20) with a statistical analysis for injured and non-injured players were included and studies with a RCT design for prevention programs. Downs&Black checklist was assessed for risk of bias for risk factors. From a total of 4067 articles, five articles met our inclusion criteria for risk factors. No studies on effectiveness of prevention programs were identified. Quality of studies included varied from fair to excellent.

Best evidence synthesis revealed moderate evidence for previous injury regardless of body location in general and fewer years of tennis experience for the occurrence of upper extremity injuries. Moderate evidence was found for lower back injuries, a previous back injury, playing >6hours/week and low lateral flexion of the neck for risk factors. Limited evidence was found for male gender as a risk factor.

The risk factors identified can assist clinicians in developing prevention-strategies. Further studies should focus on risk factor evaluation in recreational adult tennis players.     

Outdoor adventures and adolescents’ mental health: daily screen time as a moderator of changes

Research provided ample evidence that excessive screen time (ST) in adolescence has detrimental effects on psychosocial health. This paper argues that structured outdoor programs can serve as an antidote to negative health impacts of exaggerated ST. For youth with a high level of regular ST, outdoor adventures imply a break with their ‘normal’ (mediatized) lifestyle, so that greater progress in mental health can potentially arise. This hypothesis is tested in a sample of adolescents, who took part in a 10-day outdoor program. Pre-to-post program mean comparisons for stress, hedonic balance and life satisfaction show significant positive changes. However, benefits of the program are markedly greater among youths with a high level of daily ST compared to youths with low-to-moderate levels.     

Public Radio Talk Show Hosts and Social Conflict: An Analysis of Self-Reported Roles During Debates and Discussion

By interviewing and thus gathering data from 10 prominent public radio talk show hosts as to how they perceive their tasks and actions during conflict-related debates and discussions, the authors were able to categorize these self-reflections in terms of the hosts' overall communicative, directive, and procedural strategies. This article reflects on the degree to which these activities define the overall roles of public radio talk show hosts and especially on whether these social actors perceive their moderating roles as a form of third party intervention similar to the work of facilitators or mediators of social conflict.     

Prevalence and Reliability of Phonological,Surface, and Mixed Profiles in Dyslexia: A Review of Studies Conducted in Languages Varying in Orthographic Depth

The influence of orthographic transparency on the prevalence of dyslexia subtypes was examined in a review of multiple-case studies conducted in languages differing in orthographic depth (English, French, and Spanish). Cross-language differences are found in the proportion of dissociated profiles as a function of the dependent variables (speed or accuracy), the classification method (classical vs. regression-based methods), and the control sample (chronological age vs. reading level controls). The classical method results in a majority of mixed profiles, whereas the regression-based method results in a majority of dissociated profiles. However, the regression-based method appears to result in less reliable subtypes within and between languages. Finally, reading-level comparisons revealed that the phonological subtype reflects a deviant developmental trajectory across all languages, whereas the surface subtype corresponds to a delayed developmental trajectory. The results also indicate that reading speed should be considered to correctly classify dyslexics into subtypes, at least in transparent orthographies.     

Model building for conceptual change

Conceptual change is a popular, contemporary conception of meaningful learning. Conceptual change describes changes in conceptual frameworks (mental models or personal theories) that learners construct to comprehend phenomena. Different theories of conceptual change describe the reorganization of conceptual frameworks that results from different forms of activity. We argue that learners' conceptual frameworks (mental models or personal theories) resulting from conceptual change are most acutely affected by model-based reasoning. Model-based reasoning is engaged and fostered by learner construction of qualitative and quantitative models of the content or phenomena they are studying using technology-based modelling tools. Model building is a powerful strategy for engaging, supporting, and assessing conceptual change in learners because these models scaffold and externalize internal, mental models by providing multiple formalisms for representing conceptual understanding and change. We demonstrate the processes and products of building models of domain content, problems, systems, experiences, and thinking processes using different technology-based modelling tools. Each tool provides alternative representational formalisms that enable learners to qualitatively and quantitatively model their conceptual frameworks.     

Learning Relative Motion Concepts in Immersive and Non-immersive Virtual Environments

The focus of the current study is to understand which unique features of an immersive virtual reality environment have the potential to improve learning relative motion concepts. Thirty-seven undergraduate students learned relative motion concepts using computer simulation either in immersive virtual environment (IVE) or non-immersive desktop virtual environment (DVE) conditions. Our results show that after the simulation activities, both IVE and DVE groups exhibited a significant shift toward a scientific understanding in their conceptual models and epistemological beliefs about the nature of relative motion, and also a significant improvement on relative motion problem-solving tests. In addition, we analyzed students’ performance on one-dimensional and two-dimensional questions in the relative motion problem-solving test separately and found that after training in the simulation, the IVE group performed significantly better than the DVE group on solving two-dimensional relative motion problems. We suggest that egocentric encoding of the scene in IVE (where the learner constitutes a part of a scene they are immersed in), as compared to allocentric encoding on a computer screen in DVE (where the learner is looking at the scene from “outside”), is more beneficial than DVE for studying more complex (two-dimensional) relative motion problems. Overall, our findings suggest that such aspects of virtual realities as immersivity, first-hand experience, and the possibility of changing different frames of reference can facilitate understanding abstract scientific phenomena and help in displacing intuitive misconceptions with more accurate mental models.