Study on Competitive Balance of China,Japan and Europe Professional Football Leagues

This paper took match results of China Super League (CSL) , Japan J1 League (J1) and Europe big five leagues in 22 seasons (1994-2015) as samples which were chronologically divided into two periods (11 seasons for one period) , and proposed and construed a competitive balance entropy (CBE) and a performance difference index (PDI) to analyze the professional football leagues. The results showed that 1) the competitive balance of CSL and Japan J1 were lower, but the CBE of home and away matches in Japan J1 were higher, however the CBE of home and away matches in CSL were still lower;2) the competitive balance of England Premier League and Spanish La Liga were higher in 1994-2004 seasons, but had distinctly decreased since 2005 season;3) the competitive balance of whole season in German Bundesliga were ordinary, but CBE of home and away matches in German Bundesliga were higher, and the PDI among teams in away matches had greatly reduced in 2005-2015 seasons. The competitive balance of Italian Serie A were also ordinary in whole season, and in home or away matches, and the PDI among teams in away matches were greater, which decreased in 2005-2015 seasons;4) French League 1 was higher in competitive balance, and PDI among teams were also smaller.