Yesterday, Chelsea woman went to Leicester and won 9-0. Adjusted pre-match odds gave Chelsea an ~89% chance of success. While results like this are rare in the WSL, it made me think about balance in Women’s football.
Below is kernel density plot of a Theil index for the WSL using adjusted betting odds for 108 matches this season – this index can capture match-level balance, with greater values indicating more competitive contests. In this case, it ranges from 0.04 (uncompetitive matches such as above) to 1.30 (competitive matches).
The bimodal distribution with the two distinct peaks indicates the blend of balanced and imbalanced matches in the WSL this season. Keep in mind that this may relate to the structure of the odds, and I am assuming betting markets are efficient.