A regression-based approach to interpreting sports performance

Sports performance variables are unstable with opposition quality being the main source of player of variability. Therefore, performance indicators should be evaluated addressing quality of opposition. This paper uses the men's singles at the 2010 and 2011 Australian Open tennis championships to show how opposition effect can be modelled. The models are for expected performance indicator values given the World rankings of the players involved in the match. The residual values determine how much better or worse a player did than expected for each performance indicator. The residuals can be mapped onto percentage evaluation scores that address opposition quality. These interpretation scores can be used to interpret individual performances, determine performance profiles or trends in performance. This idea has been extended to address the relative strengths and weaknesses of particular opponents rather than applying the same model to all players.