While living in Portugal, Luis Amaral (Luis Amaral) loved as a child to play football and talk about it. He and his friends passionately debated who is the "best" player. But the disputes were based on private opinion. Unlike baseball and basketball, football does not provide a lot of statistical information, which makes estimation of the level of game-specific players.
Amural, grew up and became a professor at Northwestern University (Northwestern University). He combined his love of football and computer skills of its research team to find out who really is the best player on the basis of facts, not subjective opinions. The results of this study published June 16 in the journal PLoS ONE, which publishes the Public Library of Science.
Amaral and his team managed to objectively assess the level of all the players who performed in 2008 in the Champions League. Their results, closely coincided with the general opinion of sports journalists, experts, coaches and managers that subjectively choose the best players for the "Dream Team."
"In football, relatively few parameters which can account", - said Amaral, professor of chemical and biological engineering, the author of the article. "You can count the number of the player scoring goals, but if the player has scored two goals per match, this is an outstanding result. During the whole match slaughtered two or three goals, and passed two or three assists, but the team 11 people. Most of the players will be nothing to evaluate. "
To find a quantitative way to evaluate players, co-author and Northwestern graduate student Josh Weitzman (Josh Waitzman) wrote a program that was producing statistical information from the site of the Champions League in 2008. Such a comprehensive statistical information is usually available only for important matches. Amaral and Jordi Duch (Jordi Duch), Dean of Applied Mathematics and Computer Science of the University Rovira i-Virgil (Universitat Rovira I Virgili) in Spain, used this information to evaluate the players, using generalizing methods of analyzing social networks.
"You can define a network whose elements will be performing players," - said Amaral. "Connections network elements symbolizes the passing game players to each other. Ultimate goal of the player is to score a goal, so you can add another element to this network."
Team Amaral, schematically depicted move the soccer ball between players, as well as information about the impacts on target and analyzed the results.
"We were looking for routes on which the ball enters the goal," - said Amaral. "The more ways there are to the team finishing blow, the better team. And the more the ball goes through a given player, the better that player."
"We would never have been able to reach consensus with the opinion of so many experts if our method of measurement was not accurate," - said Amaral.
According to him, this method of analysis can be used not only in football. For example, companies can use it to assess the performance of its employees working on a team project. Just tell us interesting news in detail.