I enjoyed watching the UEFA Nations League final on Monday. Spain and Portugal put on a good show, and the scores were tied at 2-2 at the end of extra time. The game went to a penalty shootout. Portugal had the first penalty shot, and eventually ended up winning the shootout 5-3, after Portuguese goalkeeper Diogo Costa saved a weak shot by Alvaro Morata.
Would the result have been different if Spain had taken the first penalty shot? There certainly is conventional wisdom that says that going first in a penalty shootout conveys an advantage (a first-mover advantage in game theory terminology). The argument is that, because the team going second is often trying to come from behind, that team faces more pressure than the team going first.
However, the evidence in favour of that conventional wisdom has been challenged, most recently and most thoroughly in this new article by David Pipke (Kiel Institute for the World Economy), published in the Journal of Economic Psychology (open access). Pipke looks at the outcomes of 7116 penalty shootouts from 1970 to 2024, across top leagues and international competitions. He then tests whether the outcome deviates from a random outcome (in which the team kicking first wins 50 percent of the time). He finds that:
In soccer, the first-kicking team wins 50.2 % of the time (p =0.785) across 7,116 matches in the Flashscore data.
So, there is no statistical evidence for a first-mover advantage in penalty shootouts in football (soccer). Pipke then turns to ice hockey, which also features shootouts but where the probability of a successful shot in a shootout is much lower. Using data from 4407 shootouts in North American ice hockey leagues over the period from 2010 to 2024, Pipke finds that:
In ice hockey, the first team wins 48.9 % of shootouts (p =0.148)...
It's closer to statistical significance, but not quite. There is no evidence for a first-mover advantage in ice hockey shootouts either. Pipke then notes that his statistical tests can:
...reject the hypothesis that the first-mover’s winning probability deviates by more than 1.6 percentage points in soccer... and 2.9 percentage points in hockey from a 50:50 split, at a 1 % significance level.
Pipke then looks at some subsets of the football data, and finds that:
In 342 women’s soccer competitions, the first-moving team wins 172 times (50.3 %, p = 0.957). In youth soccer shootouts, the first-kicking team prevails in 130 out of 277 cases (46.9 %, p = 0.336).
Second, between 2017 and 2019, an alternative format, where teams alternate in an A,B,B,A pattern, was tested in various competitions to address concerns about an inherent advantage of kicking first. In 44 shootouts following this sequence, the first-kicking team won 56.8 % of the time (25 shootouts), with no statistically significant deviation from a 50:50 split (p = 0.451).
So, overall, there is no evidence of a first-mover advantage in a penalty shootout (in football or ice hockey). The result may have been different if Spain had gone first in the UEFA Nations League final penalty shootout, but going first wouldn't have given Spain a statistical advantage.
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