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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.
- Measuring collective behaviour in football teams : inspecting the impact of each half of the match on ball possessionPublication . Manuel Clemente, Filipe; Couceiro, Micael; M. L. Martins, Fernando; Mendes, Rui; Figueiredo, AntónioThe aim of this study was to inspect the influence of each half of matcha and the ball possession status on the players’ spatio-temporal relationships. Three official matches of a professional football team were analysed. From the players' locations were collected the team’s wcentroid, wstretch index, surface area and effective area of play at 9218 play instants. The results suggested that the values of teams’ dispersion and average position on the field decreases during the 2nd half of the match. In sum, this study showed that the half of match and the ball possession status influenced players’ spatio-temporal relationships, in a way that significantly contributes to the collective understanding of football teams.
- 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.
- Social network measures to match analysis in soccer : a surveyPublication . Manuel Clemente, Filipe; M. L. Martins, Fernando; Mendes, Rui; G. M. Silva, FrutuosoIn this study we will present the most common and adequate network measures to analyse graph properties and to inspect the prominence of each player on a soccer team. Both approaches can provide a range of useful information. This kind of analysis will help to identify the prominence of players and also characterize the collective organization and patterns of the teams. General measures and centrality levels will be described and the applications will be discussed. By using social network analysis will be possible to quantify the structure of play and predict some behaviour. Such methodology will add new options to the field of match analysis.
- 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.
- 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.
- 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.
- Inspecting the collective behaviours : a survey for football teamsPublication . Manuel Clemente, Filipe; M. L. Martins, Fernando; Couceiro, Micael; Mendes, RuiThe collective behaviour on football teams has been widely studied in the last few years, after decades of a deeper study about the technical and physical demands of the football. Now a days a new approach for the match analysis has been possible using the new technological advances from the multiplayer tracking systems. Therefore, the aims of this study is to provide a summarized analysis of the tactical metrics proposed and used in the last few years, trying understand how can these metrics help the match analysis. Thus, the main goal is to provide a practical perspective for the collective behaviour analysis.
- 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.