Three weeks ago in Paris, at the press conference prior to PSG-Real Madrid, this newspaper asked Benzema, the person in charge of attending the media 24 hours before the first leg of the Champions League round of 16, how he influenced this tie the suppression of the double value of the goals in the opposite field. The battering ram did not give importance to the variation set in motion by the UEFA this season, but the feeling is that his disappearance will have a major impact on the outcome of the playoffs, an impression backed up by the math. «The team that plays the second leg at home has an advantage, both with the double value of the goals as a visitor (the
known as RGV, away goal rule) as without, but at this juncture he has even more of an advantage. When playing with RGV, in 53% of the cases the team that plays at home during the round is classified. Without RGV, the percentage increases to 60%”, details ABC Julio del Corralprofessor of economics at the University of Castilla-La Mancha and one of the three authors of the article published in the International ‘Journal of Sport Finance’ on the effect of the RGV on the results of two-legged qualifiers.
of the Corral and Juan Prieto-Rodriguez, also a professor of economics at the University of Oviedo, were in charge of supervising the thesis of the economist Carlos Varela-Quintana, whose theme was focused on this matter. On February 10, the day before the start of the Champions League round of 16, they showed an extract of the article in ‘Nothing is free’, one of the most influential economics blogs at an academic level. There they explained on what data they had based their study. The results of the two-legged qualifiers of the club competitions of the CONMEBOL between 1988 and 2014. The sample contained 594 heats in which the RGV was not used (1989-2004) and 585 in which it was used (1988, 2005-2014). “The team that plays away in the return leg won about 40% of the qualifiers without the RGV. When Conmebol introduced the rule between 2005 and 2014, the percentage increased to 47%. That is to say, the application of the RGV helps to balance the qualifiers, but it is not the only relevant data. With the RGV, the number of tied ties after the regulation 180 minutes decreased significantly, from 25.93% to 8.89%. Therefore, its suppression will mean that more qualifiers need to play the extra time, a situation that will favor the teams that play the second leg at home, ”explain the three economists.
UEFA introduced in 1965 the RGV with two objectives: to promote the offensive game in the visiting teams and to reduce as much as possible the number of tied qualifiers after the 180-minute dispute. Both reasons had been in question for quite some time. It was so attractive for the visitor to score in the opposite field as it was for the local to prevent it from happening that way. “By modifying the incentives of both teams, implementing or eliminating this rule may have more relevant effects, and perhaps not contemplated by the regulators, on the probabilities of overcoming the tie of the two teams,” the economists assure.
Simeone and Mourinho have been two of the coaches who most complained about the RGV considering that the local team that plays the second leg at home, in case of extra time, played 30 more minutes of the tie with the fear of receiving a goal that penalized them twice, but they were not right. “According to data from UEFA qualifiers from 1965 to 2011, the percentage of home wins in extra time is 31% compared to 23% for away teams. The remaining 46% ended in a draw and, as a consequence, in a penalty shootout.
Important intangibles
There are three other angles reflected in the article that are also of great interest and that, according to their authors, correspond to problems of temporal inconsistency and behavioral bias. “There is a psychological pressure and a latent panic. When you are losing, let’s say you are more scared and possibly perform worse. Not scoring an away goal in the first leg seems to have a detrimental effect on performance of local teams in the second leg, despite the fact that the teams that scored in the first leg as visitors (57.3% of the total) could also exert this pressure in the opposite direction, something that has not usually occurred”, specifies del Corral.
Second, they detail that the teams do not equally value the importance of the away goal rule in both games. «Many people tend to overestimate the importance of present events with respect to future events. Do you prefer 20 euros today or 100 in five years? Most answer the first, but it doesn’t make sense. You should prefer the latter. That is what is called temporal inconsistency. With the RGV, a team that is winning 1-0 usually puts ahead not to lose that minimum advantage to score more goals. With the removal of RGV, this now will not happen so much ». Finally, risk also has its relevance. The team that plays at home with the RGV is more aware that they do not score goals than they do, because it is more important not to lose the tie than to win it. This psychological bias, known as loss aversion, was identified by Nobel laureate Daniel Kahneman and Amos Tversky in 1979.
of the Corral, Prieto-Rodriguez and Varela-Quintana they state that RGV has the positive effect of reducing the advantage that the hosts have in the second game, leading to more balanced ties. That is why they believe that the most correct measure would be to maintain the RGV during regulation time, but not abolish it: «If it is eliminated, the order of play will be much more important than it has been until now. This is obviously totally unfair. If the problem lies, as UEFA itself argues, in the enormous value of the goals scored in extra time by the visiting teams, what they could do is maintain the RGV during the 180 minutes of regulation time and play extra time without applying it » , sentence.
