A study by the University of Oviedo has shown that the change in the system used to reward wins in the European leagues, going from two to three points, has led to an increase in dirty play in football matches. The researchers used the number of red cards issued in each match during the 94/95 and 95/96 seasons, when the change was made in the scoring system, as an indicator of "sabotage" in the matches.
"If football teams achieve greater relative value for winning a match, this incentive can have unanticipated and negative effects on the game, as has happened in the Spanish league", Juan Prieto, co-author of the study and a researcher at the University of Oviedo, tells SINC.
The experts compiled data on Spanish league matches during the 94/95 season (the last season in which the winning team received two points) and in 95/96 (the season when a win started to be assigned three points) using official match data, which show the number of yellow and red cards per match, as well as the minutes when these were given and information about the minutes in the match when goals are scored.
"This information allows us to monitor not only the match itself, but also the development of the game over the course of the 90 minutes of each. This allows us to find out the precise moment at which a red card was given, and also to observe whether this happened when the receiving team was behind or ahead on the scoreboard, if they were losing or making a comeback", points out the expert.
The study confirms that the change in football league regulations, which spread throughout almost all of the European leagues in the 1990s, led to a change in the relationship between the cost and benefit of red cards, with the modification to the number of points given for winning (which started to be worth 50% more with the change to three points) having negative effects on the form of play.
More send-offs when a team is doing well
"There was a significant change in the number of red cards given during the second season in comparison with the first. We can see there has been an increase in red cards given to teams that are winning, and this can easily be attributed to the change in the points system", the study explains.
Juan Prieto adds: "The objective was to give greater incentives for attacking play and goal-scoring, but the change has had unexpected negative effects, such as the increase in dirty play".
This kind of point system is also used in the current World Cup. "If wins are important in a league of 38 matches, with 20 teams playing, even though they account for little more than 2% of the total of the league, then they take on much greater importance in a World Cup, given that only three matches are played in the first round, meaning that drawing or winning has much more impact", the researcher concludes.
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Julio del Corral, Juan Prieto-Rodriguez and Rob Simmons 'The Effect of Incentives on Sabotage: The Case of Spanish Football', Journal of Sports Economics, 11 (3): 243-260 junio de 2010. DOI: 10.1177/1527002509340666