Are penalty takers missing a trick?


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An academic study has revealed that goalkeepers in penalty shoot-outs allow themselves to be swayed by previous efforts – and that those taking the spot-kicks are not exploiting this tendency.

The Independent newspaper reported that researchers at University College London (or UCL) found that, when three consecutive spot-kicks are placed to the same side, goalkeepers have a strong tendency to dive the other way for the next penalty – regardless of the actual probability of the ball going that way.

The study looked at 37 shoot-outs in World Cup and European Cup / Champions League matches over the past 36 years.

It found that – in isolation – each penalty incident should be treated as a random act, including the side the take aims for, and where the keeper dives.

But, if the ball goes the same way three times in a row, keepers – perhaps subconsciously – sense a pattern.

“After three, it starts to be more significant than chance,” Erman Misirlisoy, the study’s lead author, said. “Around 69% of the dives are in the opposite direction to the last ball, and 31% in the same direction as last after three consecutive balls in the same direction.”

This behaviour is known as the ‘fallacy of the maturity of chances’, which presumes that previous incidents have an impact on the nature of random chance. It is also called ‘gambler’s fallacy’, and is best applied to the tossing of a coin: there is a 50-50 chance of heads or tails at each throw, regardless of past acts, yet previous landings can sway decision making.

And players taking penalties should learn to exploit this ‘gambler’s fallacy’.

“Because the goalkeeper displays the gambler’s fallacy, kickers could predict which way the goalkeeper is likely to dive for the next kick.

“That would obviously give the kicker an advantage.”

It is an advantage they do not currently take though, the study concludes.

Of course, keen followers of football will know that top-level goalkeepers prepare for penalty shoot-outs by studying each opponent’s tendency in previous matches. Sometimes this comes off – as Louis van Gaal said after his Netherlands side beat Costa Rica on penalties. Sometimes it does not, with players getting smart and mixing up their kicks.

But it is an interesting idea, and one that England – notoriously weak from the spot – could learn from. But then they’d need to get to the knockout stages first…

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