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- Network analysis in basketball : inspecting the prominent players using centrality metricsPublication . Manuel Clemente, Filipe; M. L. Martins, Fernando; Kalamaras, Dimitris; Mendes, RuiThe aim of this study was to analyse the team-members cooperation in basketball by using centrality metrics of network. Different ages were compared in this study. Forty players (10 players of under-14; 10 players of under16; 10 players of under-18 and 10 players in amateurs with more than 20 years) voluntarily participated in this study. A total of 326 units of attack were generated based on the team-members interactions and then converted in final graphs. The one-way ANOVA for the factor tactical position found statistical differences in the dependent variables of %DCentrality (F(4,15) = 13.622; p-value = 0.001; n2 = 0.784; Large Effect Size) and %DPrestige (F(4,15) = 20.590; p-value = 0.001; n2 = 0.846; Large Effect Size). In conclusion this study showed that point guard was the prominent position during the attacking organization and that social network analysis it is a useful approach to identify the patterns of interactions in the game of basketball.
- Physical and technical performances are not associated with tactical prominence in U14 soccer matchesPublication . Manuel Clemente, Filipe; Figueiredo, António José; M. L. Martins, Fernando; Mendes, Rui; Wong, Del P.The aim of this study was to analyse the association between physical/technical variables and the tactical prominence variables in U14 soccer matches. Twenty-two young amateur soccer players (13.5 0.5 years old, 5.4 0.5 years of practice, 163.3 9.8 cm in body height) from two teams of the Portuguese regional league volunteered for the study. Our results showed positive and moderate correlation between dribbling test and betweenness centrality (r = 0.324; p = 0.142), and negative moderate correlation between %fatigue index and betweenness centrality (r = −0.390; p = 0.073). Physical and technical variables had no statistical differences among tactical positions. Nevertheless, when tactical prominence of players from four tactical positions were compared, significant differences were found in terms of degree prestige (p = 0.001) and degree centrality (p = 0.002). This pilot study did not find strong correlations between physical/technical levels and tactical prominence in soccer matches.
- Using network metrics to investigate football team players’ connections : a pilot studyPublication . Manuel Clemente, Filipe; Couceiro, Micael; M. L. Martins, Fernando; Mendes, RuiThe aim of this pilot study was propose a set of network methods to measure the specific properties of football teams. These metrics were organized on “meso” and “micro” analysis levels. Five official matches of the same team on the First Portuguese Football League were analyzed. An overall of 577 offensive plays were analyzed from the five matches. From the adjacency matrices developed per each offensive play it were computed the scaled connectivity, the clustering coefficient and the centroid significance and centroid conformity. Results showed that the highest values of scaled connectivity were found in lateral defenders and central and midfielder players and the lowest values were found in the striker and goalkeeper. The highest values of clustering coefficient were generally found in midfielders and forwards. In addition, the centroid results showed that lateral and central defenders tend to be the centroid players in the attacking process. In sum, this study showed that network metrics can be a powerful tool to help coaches to understanding the specific team’s properties, thus supporting decision-making and improving sports training based on match analysis.
- There are differences between centrality levels of volleyball players in different competitive levels?Publication . Manuel Clemente, Filipe; M. L. Martins, Fernando; Mendes, RuiThe aim of this study was to analyse the variance of network centrality levels between different competitive levels and tactical positions during attacking moments. Twenty-four volleyball players (U12 – 12 players, 11.7 0.4 years old, 1.9 0.9 years of practice; Amateurs – 12 players, 24.9 4.2 years old, 12.6 2.8 years of practice) voluntarily participated in this study. The multivariate MANOVA revealed no statistical differences in the independent variable of competitive level (λ = 0.001; F(3,22) = 0.001; p-value = 1.000; = 0.001; Very Small Effect Size). Statistical differences were found in the independent variables of tactical position (λ = 1.015; F(15,72) = 2.454; p-value = 0.006; = 0.338; Moderate Effect Size). The post hoc values revealed that position 3 is the prominent player during attacking moments in both competitive levels and that position 5 reveals the smallest centrality levels in attack.
- Network process of children : influence of gender and type of game during cooperative-opposition gamesPublication . Silva, Soraia; M. L. Martins, Fernando; Sanchez, Juan; Silva, Frutuoso; Mendes, Rui; Campos, Francisco; Manuel Clemente, FilipeThe children, when playing, are communicating, since this is one of the forms of disinhibition and interaction with the group in which they are inserted (Lima, 2014). Ten children, five boys (n = 5; 5.8 ± 0.4 years old of age) and five girls (n = 5; 5.6 ± 0.5 years old of age) from a elementar school were observed during classes of motor expression. These classes took place once a week for a month, lasting one hour for each session. The interactions were observed with two cameras. It was counted as an interaction when a child passed one ball to another. The results suggest that it was in the “Free Game” that there were significant diferences between the type of game, since it was found in this one that it was easier for a player to be connected with his colleagues, being later the most requested, at the moment they had to pass the ball. Between the type of game and the gender, no significant interactions were found, as children who were the ones most requested by their classmates when they had to pass the ball were not verified. However, children who were crucial to maintaining cross-pass connections were also not checked. With regard to gender, no significant differences were found because no child, both male and female, has become important in sustaining the connections between the passes and the fact that no boys and / or girls were the most requested to make the passes with the ball. Finally, among the game types, no significant differences were found, since the children did not become essential to maintain the connection of passes between colleagues, in any of the matches played. The main objective of this study is to compare the interaction between female and male children in the type of cooperative-opposition games through Social Network Analysis.
- Technical accuracy it is associated with prominence levels in basketball?Publication . Manuel Clemente, Filipe; M. L. Martins, Fernando; Mendes, RuiThe aim of this study it was verify the association level between technical accuracy and tactical prominence variables of basketball players from different competitive levels. For such analysis, technical accuracy it was analysed using Team Sports Assessment Procedure and tactical prominence using social network analysis metrics. Forty-two basketball players from four different competitive levels (U14, U16, U18 and amateurs with more than 20 years old) it were observed during three official matches. Correlation tests revealed that %inDegree showed a large positive correlation with efficiency index (r = 0.665; p = 0.001) and very large positive correlation with volume of play (r = 0.844; p = 0.001) and performance score (r = 0.843; p = 0.001). The %outDegree showed very large positive correlation with volume of play (r = 0.743; p = 0.001), efficiency index (r = 0.710; p = 0.001) and performance score (r = 0.776; p = 0.001). This study allowed to identify that technical accuracy has great levels of correlation with tactical prominence, mainly in the case of inDegree centrality.
- Study of network process in children during cooperation gamesPublication . Ferreira, Oriana; Manuel Clemente, Filipe; Amorós, JuanPablo; G. M. Silva, Frutuoso; Mendes, Rui; Campos, Francisco; M. L. Martins, FernandoWhile playing, the child progresses in reasoning ability, develops thinking and other skills, creates social relations, understands the environment, develops knowledge and creativity, and satisfies desires (Dallabona& Mendes, 2004). Thus, playing “increases their independence, stimulates their visual and auditory sensibility, values their popular culture, develops motor skills, exercises their imagination, their creativity, socializes, interacts, rebalances, recycles their emotions, their need to know and reinvent, and thus builds their knowledge” (Dallabona& Mendes, 2004, p.4). However, the interaction with a medium that is still unknown requires the child to explore new spaces, new situations, and new contexts, watching for visible behavioral changes, acquiring patterns of communication and interaction with each other (Martins, Clemente,& Mendes, 2015), all of which is essential for the child’s development.The aim of the present study was to analyze the variance between groups of different sizes in different playful games of cooperation. The groups were randomly formed and consisted of groups of 5 (G5) or 10 (G10) members.In the results obtained, it was possible to verify that there are no significant differences in the groups of 5 and 10 children in the values of proximity prestige, whereas in centroid value statistically significant differences were found in the comparison between groups of 5 and those of 10 children, regarding interaction in the cooperation games.
- The social network analysis of Switzerland football team on FIFA World Cup 2014Publication . Manuel Clemente, Filipe; M. L. Martins, Fernando; Kalamaras, Dimitris; Oliveira, Joana; Oliveira, Patrícia; Mendes, RuiThe aim of this study was to apply the social network analysis approach to the football match analysis case. For such, it was analyzed the Switzerland national football team during the FIFA World Cup 2014 tournament. Two general network metrics (total links and network density) and two centrality metrics (degree centrality and degree prestige) were computed. Four matches from Switzerland in FIFA World Cup 2014 were analysed in this study. A total of 334 adjacency matrices corresponding to 334 units of attack were generated based on the teammates’ interactions and then converted in 4 network graphs. A total of 1129 passes were analysed. The greatest value of total links and network density was achieved in the first match (88 total links and 0.80 of density value). Degree centrality revealed that the defenders and midfielders were the players with greatest prominent values in the attacking building. Degree prestige showed that midfielders were the main targets of the team to pass the ball in the attacking process. In summary, this study showed that centrality metrics can be an important tool in match analysis to identify the style of play of football teams, revealing the most prominent tactical roles in the attacking process.
- Analysis of scored and conceded goals by a football team throughout a season : a network analysisPublication . Santos, Agostinho; M. L. Martins, Fernando; Mendes, RuiNetwork analysis can provide a new set of important information about players and teams’ behaviour throughout a match. Despite their pertinence, football analysis using network metrics is limited. Therefore, the aim of this study was to analyse the goals scored and goals conceded by a single team during a full season using network methods. Thirty-six games were analysed and from these the data about players’ connectivity in actions preceding 46 goals scored and 15 goals conceded were collected. The results showed that the most used players during the plays that resulted in the goals scored were forward players in the forward regions, mainly in the penalty area. The lateral defenders and midfield players were the players that mostly initiated the attacking plays that resulted in the goals scored. In sum, it was possible to conclude that network metrics can provide a new visualization and understanding of team-members’ behaviour, as well as characterize some patterns of play giving sport’s analysts information complementary to the traditional notational analysis.
- Outdoor play and interaction skills in early childhood education : approaching for measuring using social network analysisPublication . Duque, Isabel; M. L. Martins, Fernando; Manuel Clemente, FilipeOver the last decade, researches show evidences that the free play and the outdoor activities have positive impact on children, namely on social skills’ development as cooperation. However, the study of children interaction, especially when we want to identify and study a particular type of interaction, like cooperative interaction, requires a reflexion about the most efficient tolls and methods that can be used. With this article we intend to present a first reflective review of mathematical techniques and methods that can be potentially useful in the study of cooperative interactions with children in outdoor free play. Considering the characteristics of outdoor learning environments, which are based on freedom and free play exploitation of nature, the methods used in studies of this nature in indoor environment, tend to be more controlled by adults and more spatially limited, may not be the most effective. We intend to demonstrate that it is necessary to create a combination of mathematical techniques and methods based on the social network analysis, given the specificity of the educational outdoor environment or the space level and the dynamics of activities that there are usually generated.