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Universidad de San Andrés
Departamento de Economía
Licenciatura en Economía
Do football crowds matter?
Autor: Axel Jorgensen
Legajo: 20252
Mentor: Martin Rossi
Victoria, 23 de noviembre 2015
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Do football crowds matter?
Axel Jorgensen*
Abstract
This paper studies the extent to which crowd support provides home advantage, using
information from South American football leagues. To do this I exploit a natural experiment arising
from the fact that in 2013 the Argentine football association prohibited the attendance of visiting crowds
into football matches. I use the Uruguayan and Brazilian leagues as controls. The results suggest that
the impact of the crowd on home advantage is positive and significant.
*Student of BA in Economics, Universidad de San Andrés, Buenos Aires, Argentina.
** Many thanks to my mentor Martin Rossi for his patient guidance, Federico Bennett for his useful
comments and my friends and family for their support which helped me get to this long due moment.
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I. Introduction
In sports, the concept of "Home Advantage" implies that the team that plays at home has an
advantage over the visiting team. This home advantage has been attributed to mainly the following four
factors: (i) the team that plays at home has more supporters present encouraging them on, which
motivates the players and helps them perform better; (ii) the fans/crowd can also influence the referee's
decision and make him more likely to rule in favor of the local team; (iii) travel time, distance and form
of transportation for visitors can generate fatigue and stress, especially in different time zones; and (iv)
familiarity with the playing field by the local team can positively influence performance.
Due to multiple incidents of violence between crowds, in July 2013 the AFA barred visiting
supporters from attending football matches of the first Division, National B, First Metropolitan B and C. 1
I take advantage of these changes in regulations in Argentine football to identify the impact of the first
two factors (related to the crowd) in the home advantage.
The change in regulations in Argentine football generated a discontinuity in the relative size of
home crowd and away crowd. From one day to the next, the visiting crowd was reduced to zero and, in
some cases, was entirely replaced by local crowd, since it allowed the football clubs to sell more tickets
to their own crowd due to the additional space.
In principle, it is likely that crowd size is endogenous to team’s performance. Better performing
teams attract larger crowds that in turn may positively influence team’s performance. The change in the
regulations in Argentine football provides a source of exogenous variability in the size of the crowd.
Aside from team’s performance, I also look at the impact of the crowd on the referee's decisions,
using as additional outcomes the number of yellow cards and the number of red cards shown during the
match. I assess the quality/performance of the rivaling teams by using variables such as the difference of
points between them before the match.
1 In July 12, 2013, Javier Jerez, a fan of Lanús, died at Estadio Ciudad de La Plata, while a match was being played between Lanus and Estudiantes de la Plata as local during the 17th date of the Clausura tournament. Due to this incident the Minister of Security of Buenos Aires, Ricardo Casal, announced a ban on visiting public at all divisional football, this decision was subsequently accepted by the AFA (Argentine Football Association) and Aprevide (Agency for Prevention of Violence in Sport).
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Home Advantage has been extensively discussed in literature especially in the field of sports
statistics. There is little doubt this effect exists but it is hard to isolate the specific effects and identify
causality. According to Pollard (2008), “it is not known whether the primary effect of the crowd is to
give an advantage to the home team or a disadvantage to the away team and whether this is conveyed
directly to the players or via referee decisions influenced by the crowd.”
Among these studies there are several that look specifically to evaluate the effect of the crowd.
Ponza and Scoppa (2014) observed teams in the Italian league who share the same home stadium, but
where the ticket and season pass follows the traditional model where it favors the "local" team for that
match. By doing this they manage to control by two factors: the distance, conditions and travel time; and
familiarity with the terrain or playing field, since these factors are the same for both teams. The results
showed that the crowd increases the average goals scored by the locals and the probability of winning
the game.
Agnew and Carron (1994) found a positive relation between "density" of the fans and the Home
Advantage and Pollard (2006) argues that in the 90s, the Home Advantage fell due to a regulation
requiring all stadiums to have grandstand seats instead of allowing them to stand up which allowed for a
smaller crowd.
The literature also presents contradictory results. Several studies make use of the size of the
crowd to assess the impact on the Home Advantage. Pollard and Pollard (2005) compares the first
against the second division of several leagues and find that the magnitude of Home Advantage is very
similar between the two. Similarly, Pollard (1986) and Clarke and Norman (1995) compared the four
divisions of the English league with similar results.
With regard to the distance traveled of the visiting team, according to Pollard (2008) there is one
finding that is consistent: home advantage is reduced in local matches where no travel is involved. For
this particular result, Pollard collected evidence from the SouthEast professional football tournaments
(Pollard 2007) and specifically on the Turkish football league (Pollard et al. 2007).
In terms of familiarity with the playing field, when a team plays at home, they do so in a stadium
under known field conditions including, for example, the type and quality of the turf and the size and
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weather conditions. This concept has been difficult to prove in the literature but there are interesting
results in some studies comparing matches played on artificial grass courts (Barnett 1993), other courts
side with disproportionate dimensions (Pollard 1986) or even the ball type (Dosseville FE 2007). In
turn, other papers found that familiarity with the climate and altitude have an effect on the Home
Advantage (McSharry PE 2007).
II. Data and Descriptive Statistics
In Argentina, until December 2014 the First Division was composed of 20 professional football
clubs that play two single roundrobin tournaments each year: the initial tournament from August to 2
December and the final tournament from February to June. Only one champion was established at the
end of the tournament. The data that was retrieved for this paper dates back from February 2011 to
December 2014. For each match the data includes the match score and the disciplinary sanctions
including penalties awarded and referee’s name.
Since February 2015, a new tournament is being contested by 30 football clubs where 10 clubs
were promoted from the Division “B” joined the first division. Each team plays against all other teams
once. I decided to exclude results from this tournament since changes like this might bias the results.
For Brazil, the “Campeonato Brasileiro Série A” or the “A Series Brazilian Championship”, is
the Brazilian league for professional football clubs. Contested by 20 clubs, it operates on a system of
promotion and relegation with the “Campeonato Brasileiro Série B”. Seasons usually run fromMay to
December, with teams playing 38 matches each (playing each team in the league twice, home and away)
totaling 380 matches in the season.
Finally for Uruguay, the “Primera División” or “First división” is contested by 16 clubs with the
same structure as the argentine league. Beginning mid year with the initial tournament until December
followed by the final tournament held from February to June.
2 Roundrobin refers to a pattern or ordering whereby items are encountered or processed sequentially, often beginning again at the start in a circular manner.
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This provides a total of 4,000 observations. I am using the following variables: Win is equal to
1 if the home team wins, and 0 the home team ties or loses. Points home is equal to 3 if the local team
wins, 1 if they tie and 0 if they lose. Goals Home team is the number of goals scored by the local team
during the match. Yellow cards visitor is the number of yellow cards given by the referee to the away
team during the match. Finally, thetotal score differenceis the accumulated difference in points of both
teams before the match (a proxy of the quality of the teams).
All of these three countries belong to the The South American Football Confederation, known as
the “Conmebol”. This confederation is responsible for the organization and governance of South
American football's major international tournaments such as “Copa Libertadores” and “Copa
Sudamericana”. The same rules and regulations apply to all three tournaments and, as it can be seen
from the data description they have very similar format and tournament structure.
Neither Brazil nor Uruguay were affected by the change in Argentine regulation in June of 2013
nor by any similar one during this period that may have affected the crowd size.
Table 1 present the descriptive statistics. There is a positive difference in score between the
home and visitor team, indicating that the matches played as local tend to have more favorable results.
This provides supporting evidence in favor of the hypothesis of the existence of a home advantage. Note
that there is a significantly lower number of observations for the yellow cards since data was only
available starting in 2012 for all the disciplinary sanctions during the match. The data is generously
provided by two sports websites called www.Futbol360.com.ar and www.resultados.com.
Table 1. Descriptive statistics for Argentina, Brazil and Uruguay
Variable Observations Mean Std. Dev. Min Max
Win 4000 0.449 0.497 0 1
Points Home team 4000 1.622 1.298 0 3
Goals Home team 4000 1.403 1.186 0 6
Yellow cards visitor 2280 2.519 1.366 0 9
Total score difference 4000 0.057 8.459 43 44
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III. Methodology
I consider a match belongs to the treated group when it takes place in Argentina after the change
in the regulation, implying that the match occurred with no away crowd. The matches from Brazil and
Uruguay are considered nontreated in the entire period of the analysis.
All regressions are estimated using Ordinary Least Squares and include match fixed effect (for
example, a dummy variable that takes a value of one every time Boca Juniors plays against River Plate) in
order to control for distance traveled and field familiarity; and month/year dummies in order to control for
any seasonal effects that might have incidence on the home advantage.
The econometric model is as follows:
Yit= ai + bt + c*Treatmentit + d*TotalPointsDifferenceit + eit
Yit is any of the outcomes of interest for match “i” on time “t” ( Win, Points Difference , Goals Home,
Yellow Cards Visitor)
ai: Dummy for Match “i”
bt: Dummy for Month/Year “t”
IV. Results
The results are shown in Table 2. The regression shows that for treated matches relative to
untreated there is an increase by a factor of 0.09 in the probability of winning in favor of the home team.
This result is statistically significant under robust standard errors but lacks significance when clustered by
match. Regression [2] shows a significant increase of 0.26 in the points scored in favor of the home team
under robust check and clustered by match. The goals scored by the home team also remain statistically
significant even when clustered by match. There is an increase of 0.25 in the goals scored by the local
team. These results suggest that the crowd has a positive effect on the home team, though it may also
mean that the lack of visiting team crowd or excess of home team crowd negatively impacts the visiting
team’s performance.
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Table 2. The impact of playing with no away crowd controlling team’s quality. OLS Estimates.
Dependent variables in first row.
Win Points Home Goals home Yellow cards Visitor
Statistic [1] [2] [3] [4]
Treatment 0.0913 0.255 0.246 0.354
(0.046)* (0.122)** (0.110)** (0.178)**
[0.056] [0.149]* [0.134]* [0.224]
Total Points difference 0.011 0.031 0.017 0.006
(0.002)*** (0.0037)*** (0.003)*** (0.005)***
[0.002]*** [0.0045]*** [0.004]*** [0.007]***
Month/year Fixed effects Yes Yes Yes Yes
Team Fixed effects Yes Yes Yes Yes
Observations 3999 3999 3999 2280
R2 0.473 0.473 0.501 0.560
OLS OLS OLS OLS
Notes: The robust standard errors are shown in parentheses. The clustered standard errors are shown in brackets. *** Significant at the 1% level. ** Significant at the 5% level. * Significant at the 10% level.
In order to assess the influence that the change in the regulation might have had on the referee’s
decision I regress this against yellow and red cards. The number of observations drop significantly 3
when looking at the red cards which may explain why there is no significant effect. Even though the
yellow cards for the home team have a negative coefficient, these results are not statistically significant.
Finally, when looking at the yellow cards for the visitor the coefficient is positive and
statistically significant. There is an increase of 0.35 on yellow cards given to the away team. These
results would suggest that referees are influenced by the crowd whereby a relatively larger home crowd
or by contrast a null visiting crowd makes the referee more permissible towards the home team. This
could be related to the noise the crowd makes when a foul occurs during the match.
3 Most matches end up with no red cards.
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To this purpose, Nevill et al (2002) conducted an experiment where they asked 40 referees to
watch a videotaped game and make decisions on the incidents that occurred during the match. Half the
referees watched the game with the volume turned off and the other half with it turned on. The results
reflect that the referees that watched the match with the volume turned on (with crowd noise) granted
significantly less decisions against the home team. This results support the theory that the referees are
influenced by the crowd noise.
A very similar experiment was carried out by Nevill et al (2012) but with Muay Thai officials
(referees). This result also shows that the crowd noise increased the scores granted by this officials in
favour of the home team. These findings were attributed to effects such as informational conformity and
the use of a noise heuristic.
Finally, in table 3 I evaluate the same regressions but excluding two argentine football clubs
from the database: River Plate and Independiente de Avellaneda. The reason I exclude them from the
sample is that both this teams relegated to the B division during this period. They later promoted back to
the first division one year after relegating. Yet, since this teams are considered two of the biggest
football clubs of Argentina in terms of supporters I want to observe if their absence may have influenced
the results. As seen in the table the results are very similar and still statistically significant under a
robust regression.
V. Conclusion
Home advantage in sports is a well documented fact. However it still remains an unsolved
puzzle. It has been very hard to identify the actual causes for the existence of home advantage and how
it affects the game’s outcome. According to the literature, the main mechanisms seem to be crowd
support’s influence in the players and referee, the distance traveled by the away team and the home
team’s familiarity with the playing field.
In order to try to isolate the effect of the crowd I take advantage of a change in regulation in the
Argentine professional football league in 2013 that prohibited the away crowd from attending the games.
I use the Brazilian and Uruguayan leagues as control leagues since these leagues remained unaffected by
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this prohibition. Using fixed effects for the match between the same teams I am able to control for field
familiarity and distance traveled.
The results suggest that the crowd’s support has a strong and significant impact on the players
since there is an increase in the amounts of goals scored by the home team. It also suggests that the
referee is influenced by the crowd since there is a positive and significant increase in the amount of
yellow cards sanctioned to the away team.
As behavioral economics proposes, these results further help demonstrate that individualsare
influenced by social and emotional factors and that this has consequences on performance and outcomes,
whether it is in sport or in business.
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VII. References
Agnew, G. A., Carron, A. V. Crowd effects and the home advantage. Journal of Sport
Psychology 1994.
Barnett V, Hilditch S. The effect of an artificial pitch surface on home team performance in
football (soccer). J R Statist Soc A 1993.
Clarke SR, Norman JM. Home ground advantage of individual clubs in English soccer.
Statistician 1995.
Dosseville FEM. Influence of ball type on home advantage in French professional soccer.
Percept Mot Skills 2007.
McSharry PE. Altitude and athletic performance: statistical analysis using football results. BMJ
2007.
Myers, T. , Nevill, A. & AlNakeeb, Y. The Influence of Crowd Noise upon Judging Decisions
in Muay Thai. Advances in Physical Education. 2012.
Nevill AM, Balmer NJ, Williams AM. The influence of crowd noise and experience upon
refereeing decisions in football. Psychol Sport Exerc 2002.
Pollard R. Home Advantage in Football: A Current Review of an Unsolved Puzzle. J Sports Sci
2008.
Pollard R. Home advantage in soccer: a retrospective analysis. J Sports Sci 1986.
Pollard R. Worldwide regional variations in home advantage in association football. J Sports Sci
2006.
Pollard R, Pollard G. Ventaja de ser el equipo local en fútbol: una reseña de su existencia y
causas. Rev Int Fútbol Ciencia 2005.
Pollard R, Seckin A. Why is home advantage in Southeast Europe the highest in the world?
12th European Congress of Sport Psychology 2007.
Ponza M., Scoppa V. Does the Home Advantage Depend on Crowd Support? Discussion Paper
2014.
Seckin A, Pollard R. Home advantage in Turkish professional soccer. J Sports Sci Med 2007.
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VI. Appendix
Table 3. The impact of playing with no away crowd controlling team’s quality. OLS Estimates.
Dependent variables in first row. Without River Plate and Independiente
Win Points Home Goals home Yellow cards Visitor
Statistic [1] [2] [3] [4]
Treatment 0.108 0.294 0.262 0.408
(0.05)** (0.129)** (0.117)** (0.19)**
[0.06]* [0.305]* [0.141]* [0.238]*
Score Difference (Total) 0.011 0.062 0.018 0.006
(0.001)*** (0.007)*** (0.004)*** (0.005)
[0.002]*** [0.009]*** [0.004]*** [0.007]
Month Fixed Effects Yes Yes Yes Yes
Team Fixed effects Yes Yes Yes Yes
Observations 3656 3656 3655 2112
R2 0.479 0.489 0.507 0.56
OLS OLS OLS OLS
Notes: The HuberWhite robust standard errors are shown in parentheses. The clustered standard errors are shown in brackets. *** Significant at the 1% level. ** Significant at the 5% level. * Significant at the 10% level.
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Table 4. The impact of playing with no away crowd controlling team’s quality on disciplinary
sanctions. OLS Estimates. Dependent variables in first row.
Yellow cards
home Yellow cards
visitor Red cards
home Red cards
visitor
Statistic [1] [2] [3] [4]
Treatment 0.138 0.355 0.077 0.355
(0.176) (0.178) (0.055) (0.178)
[0.221] [0.224] [0.07] [0.224]
Score Difference (Total) 0.011 0.033 0.002 0.033
(0.005) (0.013) (0.002) (0.013)
[0.007] [0.017] [0.002] [0.017]
Month/year Fixed effects Yes Yes Yes Yes
Team Fixed effects Yes Yes Yes Yes
Observations 2280 2280 2280 2280
R2 0.458 0.563 0.509 0.563
OLS OLS OLS OLS
Notes: The HuberWhite robust standard errors are shown in parentheses. The clustered standard errors are shown in brackets. *** Significant at the 1% level. ** Significant at the 5% level. * Significant at the 10% level.
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