By IANS,
Washington : A new method has been devised to measure and rank the success of soccer players based on an objective measure of performance instead of opinion.
Luís Amaral, professor at Northwestern University and his research team found that unlike baseball and basketball, there isn’t a lot of statistical information detailing how each soccer player contributes to a match.
Though their analysis, Amaral and his team were able to objectively rank the performances of all the players in the 2008 European Cup tournament.
Their results closely matched the general consensus of sports reporters as well as the team of experts, coaches and managers that subjectively chose players for the “best of” tournament teams.
“In soccer there are relatively few big things that can be counted. You can count how many goals someone scores, but if a player scores two goals in a match you can only divide two or three goals among eleven players. Most of the players will have nothing to quantify their performance at the end of the match,” Amaral said.
To find a quantitative way to rank players, co-author and Northwestern graduate student Josh Waitzman first wrote a software to pull play-by-play statistical information from the 2008 Euro Cup website.
This type of extensive statistical information is usually only gathered for important matches, Amaral said.
Amaral and Jordi Duch, the paper’s first author and assistant professor at Universitat Rovira I Virgili in Spain, used the data to quantify the performance of players by generalising methods from social network analysis.
Amaral’s team mapped out the flow of the soccer ball between players in the network as well as shooting information and analysed the results.
“We looked at the way in which the ball can travel and finish on a shot. The more ways a team has for a ball to travel and finish on a shot, the better that team is. And, the more times the ball goes through a given player to finish in a shot, the better that player performed,” said Amaral.
“It would never happen by chance that we would get such striking agreement with the opinion of so many experts if our measure wasn’t good,” Amaral said, according to a Northwestern release.
He said this kind of analysis can be used outside of the soccer world, too. Companies could use the method to rank and evaluate the performance of employees working together on a team project.
The results were published in PLoS ONE.