Statistical Properties Of The Mutual Transfer Network Among Global Football Clubs

Football is the most popular sport in the world, and one of the most interesting events is the transferring of football players among various clubs. Based on 470,792 transfer records among 23,605 football clubs in 206 countries and regions, we construct a mutual transfer network and investigate its basic topological characteristics related to node degree k, edge weight w and node strength s. We find that the distributions can be well fitted by bimodal distributions for k and s or a power-law tail distribution for w. By studying the features of neighbor nodes or edges, we find that the mutual transfer network exhibits assortative mixing for most nodes or clubs but disassortative for clubs with very large degrees. We also observe nonlinear correlations among the different types of measures. Our work sheds new lights into the investigation of the characteristics of football transfer activities.