Home advantage has been a widely studied phenomena in football. The benefits are said to mostly come from reduced travel and the presence of home Fans. Home fans pride themselves on the impact they have on helping their team win. However, it has been difficult in the past to determine how much effect comes from just the fans.
The majority of the 2020–21 Premier League season was played without fans. A few games included minor attendance, but not close to levels seen in previous seasons. This gives the perfect opportunity to determine how much impact the home fans truly have, and for which teams the impact is greatest.
In this post, I analyse historical Premier League data from the last ten seasons – that is, from the 2012–13 season to the current one (2021–22). First, I will try to answer the question: do the fans increase the home advantage in general across the league? Then, I will specifically look at each team and determine which fans have the largest impact on their team’s home results.
The summary states the key findings for those in a rush, whilst the details section goes into further detail on these findings for those who want more information.
Summary
The 2020–21 season saw a dramatic decrease in the home win rate and increase in the away win rate. For the only time in the last ten seasons, the away win rate exceeded the home win rate. This shows that overall, across the league, the home fans have an impact on the result. With fans returning, the current season has seen the rates return somewhat to pre-pandemic levels.
A home fans factor was calculated for each team, which is based on the proportion of points from home games in the 2020–21 season compared to the 8 seasons preceding it, for the teams in the 2020–21 Premier League season.
Fulham was shown to have the biggest home fans factor, implying that the presence of Fulham fans has the greatest positive impact on the result for any team in the league. On the other end, Southampton was shown to have the lowest, implying that Southampton play better at home without fans present. The factor for all the teams is shown in Figure 4 in the details section.
The presence of home fans was shown to have a positive impact on the result of a game, towards the home team. However, the stadium capacity was shown to have no effect on the home fans factor. This suggests that the presence of fans is important, but the amount is not.
The details
Part 1: Overall
First, the effect of home fans is looked at across the whole league for the past ten seasons. Figure 1 shows the win rate for home and away teams across the seasons considered. For the eight seasons before the pandemic, the home win rate never dips below 40%, and the away win rate never exceeds 35%. In fact, the two rates never come within 10% of each other.
For the 2020–21 season, the away win rate exceeds the home win rate, giving evidence that the home fans play an important role on average across the league. In fact, it may even indicate that most (if not all) of the home advantage comes from the fans, as the travel factor was still present. Interestingly, the final third of the 2019–20 season was played without fans, but the home win rate is in line with previous years. However, the overall average attendance was not dramatically lower than previous seasons (shown in Table 1 in the appendix).
For the 2021–22 season, the home rate is again higher, but the difference is less extreme than seen previously. As the average attendance is back to pre-pandemic levels, this suggests a greater tendency towards draws. Indeed, the draw rate (29%) is the highest from all the seasons considered. However, as the season is incomplete, this may simply be statistical fluctuations, and the difference may increase as the season progresses.
Another way to see the impact is to look at the rolling win rate since the 2012–13 season, shown in Figure 2. The red lines show the duration in which no fans were present in the stadiums. In this period, the rolling rate clearly drops. Given that the rate is weighted by all previous eight seasons, the drop is quite dramatic.
So, the next question is: where did these extra away wins come from in the 2020–21 season? Looking at the total number of home and away goals (Figure 3) shows that the number of goals has stayed relatively consistent over the years within the two categories. However, for the 2020–21 season we see the most drastic change. Whilst there are still more home goals, the difference is now much smaller. In fact, there were only four more home goals. So, unsurprisingly, the away win rate increased because the away teams were scoring more and the home teams less.
Performing a Student’s t-test between the average attendance per season (shown in Table 1 in the appendix) and the away win rate shows a significant correlation of –0.72 (with a p-value of 0.02<0.05), suggesting that higher fan attendance leads to a lower away win rate. Hence, we can conclude that the attendance of fans has a statistically significant effect on the away win rate.
Part 2: Team specific
Here, I seek to investigate the specific impact that each team’s fans have on their performance. To do this, I will be comparing the eight seasons before the 2020–21 season directly to the 2020–21 season. I won’t be including the current season, because the season is incomplete. I will group the pre-pandemic seasons. This comparison only uses the teams involved in the 2020–21 season, excluding Leeds United and Sheffield United, as they were not in the Premier League in the seasons considered here before the pandemic.
To quantify the impact of the fans, we could look at the difference in home win rates between pre-pandemic and the 2020–21 season for each team. However, a team may have a lower/higher win rate solely due to a difference in form that season. Instead, I will look at the proportion of total points which come from home games in a season. This way, the overall form of a team is irrelevant, but instead the home form is considered relative to the away form. I will be comparing the proportion of a team’s total points from home games in the pre-pandemic seasons to the 2020–21 season. The difference between the two will be termed the home fans factor (HFF), defined as:
Figure 4 shows the HFF for each team. A positive value indicates that the proportion of points from home games has decreased in the 2020–21 season for that team, indicating that the home fans normally have a positive impact. A negative value indicates the contrary. As the overall home win rate has decreased across the league when the fans are not present, it is no surprise that the HFF is positive for most teams. The exceptions are Crystal Palace and Southampton. These two teams seem to prefer playing in an empty stadium – perhaps they don’t deal with fan pressure as well. The HFF is largest for Fulham and Everton. This suggests that the fans for these two clubs have the greatest impact on the outcome of a home game.
As a final point, comparing the HFF to each team’s stadium capacity reveals no significant correlation, shown in Figure 5. This suggests that the size of the stadium does not influence the home team’s performance. In fact, the team with the largest HFF (Fulham) also has the lowest capacity. Despite Fulham not being known for it’s particularly rowdy atmosphere, compared to places like Anfield, the team can probably play with slightly less pressure. So, perhaps the best performances at home come from a gentler atmosphere.
In conclusion, the presence of home fans was shown to decrease the away win rate on average across the league. Fulham was shown to have the most impactful fans. However, the capacity of the stadium was shown to have no correlation with the HFF. This suggests that whilst the presence of the fans is important, the actual number is relatively unimportant.
Sources:
Data: https://www.football-data.co.uk/englandm.php
Software used: R
Further reading:
Home advantage during the COVID-19 pandemic: Analyses of European football leagues
Appendix:
