A CUSUM tool for retrospectively evaluating team performance: the case of the English Premier League. Issue 3 (23rd April 2020) - Beggs, Clive
Abstract : Purpose: Despite being a widely used management technique, cumulative sum (CUSUM) analysis remains almost unheard of in professional sport. To address this, CUSUM analysis of soccer match data from the English Premier League (EPL) was performed. The primary objective of the study was to evaluate CUSUM as a tool for assessing "on-field" team performance. As a secondary objective, the association between managerial change and team performance was evaluated. Design/methodology/approach: CUSUM was applied retrospectively to goal difference data for six EPL teams (Arsenal, Chelsea, Everton, Liverpool, Manchester United and Tottenham) over 23 consecutive seasons from 1995 to 2018. This was supplemented with change point analysis to identify structural changes in mean goal difference. Succession was evaluated by mapping historical managerial changes onto the CUSUM plots for the respective clubs. Findings: CUSUM analysis revealed the presence of structural changes in four clubs. Two structural change points were identified for both Chelsea and Everton, one for Manchester United and Tottenham and none for Arsenal and Liverpool. Relatively few managerial changes coincided temporally with structural changes in "on-field" performance, with most appointments having minimal impact on long-term team performance. Other factors (e.g. changes in ownership) appear to have been influential. Research limitations/implications: The study was limited by the fact that only successful teams were investigated. Practical implications: CUSUM analysis appears to have potential as a tool for executive decision-makers to evaluate performance outcomes in professional soccer. Originality/value: The study is the first of its kind to use CUSUM analysis to evaluate team performance in professional soccer.