The comparison of normalization procedures based on different classification systems

In this paper, we develop a novel methodology within the IDCP measuring framework for comparing normalization procedures based on different classification systems of articles into scientific disciplines. Firstly, we discuss the properties of two rankings, based on a graphical and a numerical approach, for the comparison of any pair of normalization procedures using a single classification system for evaluation purposes. Secondly, when the normalization procedures are based on two different classification systems, we introduce two new rankings following the graphical and the numerical approaches. Each ranking is based on a double test that assesses the two normalization procedures in terms of the two classification systems on which they depend. Thirdly, we also compare the two normalization procedures using a third, independent classification system for evaluation purposes. In the empirical part of the paper we use: (i) a classification system consisting of 219 sub-fields identified with the Web of Science subject-categories; an aggregate classification system consisting of 19 broad fields, as well as a systematic and a random assignment of articles to sub-fields with the aim of maximizing or minimizing differences across sub-fields; (ii) four normalization procedures that use the field or sub-field mean citations of the above four classification systems as normalization factors; and (iii) a large dataset, indexed by Thomson Reuters, in which 4.4 million articles published in 1998–2003 with a five-year citation window are assigned to sub-fields using a fractional approach. The substantive results concerning the comparison of the four normalization procedures indicate that the methodology can be useful in practice.     

When a robot is social: spatial arrangements and multimodal semiotic engagement in the practice of social robotics

Social roboticists design their robots to function as social agents in interaction with humans and other robots. Although we do not deny that the robot's design features are crucial for attaining this aim, we point to the relevance of spatial organization and coordination between the robot and the humans who interact with it. We recover these interactions through an observational study of a social robotics laboratory and examine them by applying a multimodal interactional analysis to two moments of robotics practice. We describe the vital role of roboticists and of the group of preverbal infants, who are involved in a robot's design activity, and we argue that the robot's social character is intrinsically related to the subtleties of human interactional moves in laboratories of social robotics. This human involvement in the robot's social agency is not simply controlled by individual will. Instead, the human-machine couplings are demanded by the situational dynamics in which the robot is lodged.     

Relevance-based language modelling for recommender systems

Relevance-Based Language Models, commonly known as Relevance Models, are successful approaches to explicitly introduce the concept of relevance in the statistical Language Modelling framework of Information Retrieval. These models achieve state-of-the-art retrieval performance in the pseudo relevance feedback task. On the other hand, the field of recommender systems is a fertile research area where users are provided with personalised recommendations in several applications. In this paper, we propose an adaptation of the Relevance Modelling framework to effectively suggest recommendations to a user. We also propose a probabilistic clustering technique to perform the neighbour selection process as a way to achieve a better approximation of the set of relevant items in the pseudo relevance feedback process. These techniques, although well known in the Information Retrieval field, have not been applied yet to recommender systems, and, as the empirical evaluation results show, both proposals outperform individually several baseline methods. Furthermore, by combining both approaches even larger effectiveness improvements are achieved.     

Anthropometric,physiological and maturational characteristics in selected elite and non-elite male adolescent basketball players

Abstract

We investigated the anthropometric, physiological and maturation characteristics of young players (13–14 years old) associated with being successful in basketball. Body parameters were measured (stature, total body mass, skinfolds and lengths) and physiological capacities were assessed by endurance, sprint (20 m), jump and dribbling tests. Chronological age (CA) was recorded and maturity estimated using predicted age at peak height velocity (APHV). Anthropometric analysis indicated that elite players were taller, heavier and had a higher percentage of muscle. Further, physiological testing showed that these elite players perform better in jump, endurance, speed and agility tests (especially in the agility and ball tests). In addition, these skills are correlated with point average during the regular season. More basketball players born in the first semester of the year are selected and there is a predominance of early-maturing boys among those selected for the elite team. Those who are more mature have advantages in anthropometric characteristics and physiological test results. In conclusion, around puberty, physical and physiological parameters associated with maturity and CA are important in determining the success of basketball players. These findings should be taken into account by trainers and coaches, to avoid artificial bias in their selection choices.     

Comparative analysis of sequentiality using SDIS-GSEQ and THEME: A concrete example in soccer

Abstract

Within an observational design aimed at studying what type of soccer is better adapted to the possibilities of the 11–12 year-old child, a comparison was made of the results obtained using two fully consolidated analysis techniques in observational methods, and which form the basis in the development of two respective software programs: SDIS-GSEQ and THEME, which allow one to detect the existence of sequential patterns hidden in a data set. This work is intended to shed light on the comparison of results obtained using these two analysis techniques. In particular, the data used for the analysis are multicode event data (using the lexicon of the sequential analysis), and do not incorporate the duration parameter. Accordingly, for the detection of regular structures using the THEME program (T-patterns), a constant duration has conventionally been assigned to each occurrence. Using THEME, among the greatest number of sequential structures detected, diachronic and synchronic correspondence was observed (T-patterns reflecting identical multi-events) with each and every one of the sequential patterns obtained using the lag technique, by the SDIS-GSEQ software. This coincidence strengthens the link between the algorithms that support SDIS-GSEQ and THEME. The results indicate that 7-a-side soccer and 9-a-side soccer types facilitate the spatial mastery of the game by the child, compared with the adult form, 11-a-side soccer.     

Observational analysis of the offensive sequences that ended in a shot by the winning team of the 2010 UEFA Futsal Championship

Abstract

This article analyses the offensive phase of the national team than won the 2010 UEFA Championship. More specifically, the observational sampling includes all plays in which the Spanish national futsal team managed to “shoot” in the competition in question. This data was obtained by adapting an observational and recording tool typically used for football to the technical specifications of futsal; the SOF-CODER (Jonsson et al., 2006). Two types of analysis have been performed. One statistical analysis using the SPSS programme, version 15.0, the most relevant results from which refer to the significant differences found on linking: the zone from which the shot is made and the type of shot (χ² = 55.821, P = 0.006); and the contact surface used and the type of shot (χ² = 30.293, P = 0.017). And another, using the Theme programme, version 5.0, through which regular behaviour structures (temporal patterns) have been detected within the plays that include shooting. The temporal patterns obtained – in addition to elaborating on the relationship between the area from which the shot is made, the contact surface used and the type of shot – enable a tactical interpretation of the technical actions that support the development of the offensive phase of futsal.     

Effects of plyometric jump training on the physical fitness of young male soccer players: Modulation of response by inter-set recovery interval and maturation status

ABSTRACT

The effects of plyometric jump training on the physical fitness of male youth (age = 10–17 years) soccer players was examined in relation to inter-set recovery intervals and the maturity of the players in a single-blind, randomized-and controlled crossover trial. Jumping tests and kicking velocities were measured before (T₀), after a 6 week control period (T₁), after 6 weeks of plyometrics (T₂), after 6 weeks of wash-out (T₃), and after a further 6 weeks of plyometrics (T₄). Subjects were divided into pre- and post- peak-height-velocity (PHV) groups, and were randomly assigned to 30 s or 120 s inter-set intervals during periods T₂ and T₄. Any changes in jumping and maximum kicking velocities during T₁ and T_3, had trivial effect sizes (0.01–0.15), but small to moderate improvements (effect size = 0.20–0.99) were observed in both groups during T₂ and T₄. Gains in pre-PHV players were similar for the two inter-set intervals, but gains in post-PHV players were greater (p < 0.05) with an inter-set recovery of 120 s than with a 30 s recovery. We conclude that plyometric jump training improves the physical fitness of adolescents, irrespective of their maturity, but that in older individuals gains are greater with a longer inter-set recovery interval.     

Loneliness,personal and social well-being: towards a conceptualization of the effects of cyberbullying / Soledad,bienestar social e individual: hacia una conceptualización de los efectos del cyberbullying

This paper examines the effects of cyberbullying using a mixed method approach, by combining interviews, focus groups and a survey of 7,000 students. In the inductive stage, and following an axial coding analysis, we identified 153 concepts related to conflicts, which were divided into three thematic units to explain the greater impact of cyberbullying: (1) social distance; (2) privacy exposure; and (3) range of the material. The survey concluded that: (1) the victims of bullying and cyberbullying present higher levels of loneliness and lower levels of social well-being compared to non-bullied students, and those who were bullied in both channels presented higher levels of loneliness and lower levels of social well-being than those who were bullied in only one of them; (2) the victims of cyberbullying showed lower levels of individual well-being compared with those who had never been bullied, as with those who suffered face-to-face bullying. This difference was explained by testimonies indicating that most of the cyberbullying was related to intimate content, which has a higher impact on image perception.     

School and community factors involved in Chilean students’ perception of school safety

Identifying and understanding predictors of school safety perceptions is important due to its consequences for students. However, it is not clear what school‐related factors most contribute to explaining students’ perception of school safety, and how they relate to community‐related factors such as neighborhood safety. The purpose of this study was to understand the factors associated with Chilean elementary and middle school students’ perceptions of school safety. We used a sample of 5,455 students from low socioeconomic status public schools, and analyzed the predictive value of peer physical and verbal victimization; teacher and school staff victimization; teacher's social support; and perception of safety in the students’ neighborhoods on perceptions of school safety. Findings showed that although different forms of school violence, particularly peer physical victimization and physical and sexual victimization from teachers and school staff, contribute to students’ perception of school safety, the highest contribution came from students perceiving their neighborhoods as unsafe. In contrast, teacher social support contributed to increased levels of perceived school safety. We discuss the need for school‐based interventions that address physical victimization and engage teachers in prosocial and less punitive approaches to foster a positive and safe school climate, and in fostering school–community partnerships.