Network analysis of the worldwide footballer transfer market

¹ Research Institute of Sports Economics, East China University of Science and Technology Shanghai 200237, China
² Research Center for Econophysics, East China University of Science and Technology - Shanghai 200237, China
³ Department of Finance, East China University of Science and Technology - Shanghai 200237, China
⁴ Department of Mathematics, East China University of Science and Technology - Shanghai 200237, China
⁵ Center for Polymer Studies and Department of Physics, Boston University - Boston, MA 02215, USA

^(a) wxzhou@ecust.edu.cn

Received: 1 November 2018
Accepted: 4 January 2019

Abstract

The transfer of football players is an important part in football games. Most studies on the transfer of football players focus on the transfer system and transfer fees but not on the transfer behavior itself. Based on the 470792 transfer records from 1990 to 2016 among 23765 football clubs in 206 countries and regions, we construct a directed footballer transfer network (FTN), where the nodes are the football clubs and the links correspond to the footballer transfers. A systemic analysis is conduced on the topological properties of the FTN. We find that the in-degrees, out-degrees, in-strengths and out-strengths of nodes follow bimodal distributions (a power law with exponential decay), while the distribution of link weights has a power-law tail. We further figure out the correlations between node degrees, node strengths and link weights. We also investigate the general characteristics of different measures of network centrality. Our network analysis of the global footballer transfer market sheds new lights into the investigation of the characteristics of transfer activities.