Stirling research on penalty kicks scores at global conference

The work of a University of Stirling economist into penalty kicks in football has won a prestigious competition in the USA.

Dr Carl Singleton, an expert in sports economics, is co-author of a study which found that professional footballers trade off the chance of scoring a goal with the possibility of missing the target, to save face.

The study by the Universities of Stirling and Reading, and Syracuse University, beat six other finalists to win the annual research paper competition at last week’s MIT Sloan Sports Analytics Conference in Boston, a major forum for sports professionals, business leaders, and researchers to discuss trends, analytics and innovation in the global sports industry.

The research, which is based on game theory, studied 536 penalty kicks from the UEFA Champions and Europa Leagues. It reveals that those taking a penalty kick are sometimes sacrificing the most effective strategic shot placement and instead prioritising their credibility and perceived performance and skill.

The shot location choices suggest that the average penalty kick taker trades off a one percentage point chance of scoring with a three percentage point reduction in the chances of missing the target completely. In other words, an additional 3 in every 100 kicks are on target at the expense of 1 in a hundred kicks being unsuccessful.

These results suggest that penalty kick takers are happy to trade off the chance of scoring a goal with looking like they made a mistake by missing the target.

Given the choice of aiming for the top corner of a net, which is statistically more likely to result in a goal but also runs the risk of missing the goal completely, kick takers are choosing to shoot towards other areas of the net where not only does the goalkeeper have a greater chance of making a save but the overall kick success rate is lower.

The study draws comparisons to elite basketball players, such as Shaquille O’Neal and Andre Drummond, who have stated publicly that they won’t attempt underhand free throws despite evidence that they could improve their rates of scoring.

Dr Singleton, Senior Lecturer in Economics at the University of Stirling Management School, said: “Professional football and soccer players care about missing the goal because this looks like they’ve made a big mistake, by not even testing the goalkeeper. Our findings show that they are not shooting to areas of the goal where they would have a high chance of scoring in.

They are happy to trade off their chances of scoring a goal with looking credible as professionals who can at least make the goalkeeper work, meaning they’re not taking shots to the top corner as often as they should.

“To the coach and the team, a kick missing the goal versus being saved by the goalkeeper is the same outcome, but to the player that distinction clearly matters.”

He added: “It is important that football players learn that it’s OK to fail, and that the stigma attached to negative outcomes such as this is taken away. Coaches need to help players develop more of a no-fear mentality.”

Do Behavioral Considerations Cloud Penalty-Kick Location Optimization in Professional Soccer: Game Theory & Empirical Testing using Polynomial Regression and ML Gradient Boosting, which is awaiting journal publication, is available to download.