Don’t you just love the term “scoreless action”. That describes the average soccer match. One of my colleagues suggested to me that the game would be a lot quicker if they went straight to the penalty shoot-out.
It turns out that there is some merit in that idea. Liam Lenton – a senior lecturer at La Trobe University and a fine sports economist – has an article in the Fin Review exploring a variation of that idea. Rather than having a draw, then extra time and then a shoot out – making for a very boring defensive game – rather have the 90 minute game, then the shoot-out, and then the extra time. If the score is still equal after the 90 minutes and extra time, then the retrospective shot-out result establishes the winner.
The rule does not alter incentives in the sacrosanct regulation time. However, the extra time incentive effect, shown by University of Southern California theoretical economist Juan Carrillo, is two-fold: the shootout loser becomes more attacking than currently as they cannot win without scoring.
The shootout winner becomes more defensive as denying the opposition guarantees victory. Ultimately, which of these two effects is stronger in the data governs whether this rule change is an improvement.
In our study, appearing in last December’s issue of the Journal of Sports Economics, applying data describing over 500,000 matches in many international competitions, we estimated this net effect via econometric regression analysis. Scoring probabilities in two groups of matches were compared – the treatment group closely simulates both teams’ incentives of the proposed rule to a control group representing the current rule.
Our results suggest that in the World Cup, and other elite competitions, the probability of extra time producing at least one goal would increase by 45 per cent to 60 per cent under this rule, variant to influences such as home-ground advantage, tournament stage and relative team ability.
Put differently, the proportion of scoring extra times would rise from approximately 50 per cent to above 75 per cent.
I suspect the “sacrosanct regulation time” (whatever that really means) precludes a penalty shoot-out before the game actually starts.