Defence performance analysis: Social network analysis

Abstract

There is little study concerned game structure of women's sevens rugby. Because the game time is only 14 minutes (7 minutes half), the temporal performance would be a decisive factor. It might suggest the characteristics of current world women's sevens rugby and each union. This study clarified the temporal structure of "try scoring rate" (frequency of tries in own possession (secs)), and "try conceding rate" (frequency of tries in oppose possession (secs)). With adding two manipulated factors from "opposition 22m entry try success (attack)" and "own 22m entry try success (defence)", total four factors were investigated for the world ranking clusters. Data were picked up from opened homepage of World Rugby game analysis 2016-2017 women's sevens series. Two-dimensional space showed the relationship of "try scoring rate" and "try conceding rate" (avg. = 79 secs) with mapping the world fifteen union's performances. It suggested world ranking structure. Non-hierarchical cluster analysis was attempted in order to explore the possibility of grouping. Interesting differences were observed among the number of iterations. The 5-iteration process setting showed top group by top 7 unions. The 1000-iteration process setting showed top group by top 3 unions. (explained 96% of point variability). Clustering the world women's sevens rugby was tried from the temporal structure analysis of some attack-defence performances. In non-hierarchical cluster analysis, the number of clusters needs to be determined by the analyst, and there is no established method to calculate the optimal number of clusters automatically. The number of women's sevens games is also limited. Development of the optimal algorithm under this condition would be desired.