Corona, soccer and missing fans in the stadium
What effect do the missing fans have on results in Europe’s largest soccer leagues?
One afternoon in March 2021, a colleague from mediaman and I asked ourselves, if the missing fans in the stadium do have an impact on the results in Europe’s largest soccer leagues — primarily in the German Bundesliga.
Luckily we’re both developers and soccer fans, so we immediately started collecting data of the Bundesliga and some other European leagues. Fetching, storing, analyzing and displaying data is our daily work at mediaman.
Note that this article will cover some conceptional nerd stuff as well as the results that I see in our analysis.
Since March 2020 the stadiums all over Europe were quite empty due to the Corona pandemic. In Germany the Bundesliga stopped playing for a while and restarted in May but without any fan in the stadium.
Season 2020/2021 started quite normal in September but still without fans. After a very bad first half of the season of my personal favorite club, we had to investigate further and see if the results of the matches changed.
The nerd stuff
In this case, collecting the data was quite easy. First, we fetched the results from previous seasons for later comparison between “Non-Corona-Seasons” and “Corona-Seasons”. Then, every monday after the matches in the Bundesliga were finished, we fetched the results by simply requesting data from an API. Next, we stored all results in a DynamoDB table in the AWS cloud.
The rest is pretty easy as well: We created a node.js backend with API Gateway and Lambda functions to enable the frontend application to fetch these results. In the frontend, the data is grouped by wins, draws and defeats of the matches at home and simply displayed with a D3.js chart. For this case we decided to use a horizontal stacked bar chart to make comparison between seasons easier to read. Because we only want to compare the results per season, the x- and y-axes are simple: The x-axis just displays numbers between 0 and about 300 — as there are about 300 matches in German Bundesliga per season (note: this can change for other European leagues). The y-axis displays the seasons.
The result looks like this:
The results will change in a way that more teams would lose matches at home, because the away team does not have to fight against both: 11 players in the home team and the cheering fans.
For better comparison, we decided to display data from two seasons before Corona changed our way of living until now.
Remember that everything changed midway through season 2019/2020.
Less loses, more wins at home
When comparing season 2019/2020 it’s obvious that something had happened. There are about 20% more wins at home (for the home team) than in both seasons before. Also, around 11% less loses at home.
Comparing season 2020/2021 with season 2019/2020 the results seem to “normalize” again. The 20% more wins at home are nearly gone and the 11% less loses at home reduced to about 7% less loses at home. Hence, there were more draws at home than in season 2019/2020 and even 2018/2019.
But when looking at season 2018/2019 and 2020/2021, the difference is minimal. The wins at home are about the same, a few more draws at home and a few less loses at home but nothing really noticeable.
Fans do not have an impact on the results?!
Seeing this analysis, it seems that fans at home do not really make an impact on the home teams result.
For me, as I had experienced thrilling matches at the end of the season, seeing my team fighting against going down to league 2, cheering 90 minutes for my team and finally seeing them win at home, makes me feel weird about these results. Does that mean that me, as a season card holder, am nearly unimportant for my team to win or lose at home?
With this in mind, I started reflecting these results and trying to get deeper into analysis. There are studies which quote that there is a home advantage in sports (e.g. this one) — for example the crowd influencing the referees and also pushing the teams.
Other papers also quote that there are a lot of reasons for the home advantage. From less travel time to higher comfort zone, the whole surrounding is the basis for a better physical and mental well-being of the players.
But this does not explain the difference between season 2019/2020 and the previous and next season. My personal assumption is: Because the lockdown occurred right in the middle of the season, the teams had no time to get used to empty stadiums. Hence, one factor of all the home advantage factors changed. To prove this thesis, another analysis of data would be needed. The distribution of the home wins, draws and loses over time in regard of the Corona pandemic should be analyzed. When did the wins increased — during the complete seasons or after Corona lockdown?
Coming back to my thesis for the changes only happening in 2019/2020: After the season 2019/2020 was finished and all the players and staff were to some extend “used” to empty stadiums, the new season 2020/2021 felt a bit more “normal” or at least empty stadiums weren’t a new phenomenon. This would explain the quite “normalized” results in the past season.
I am a bit disappointed about the results of this data analysis as I hoped to see our thesis being proved — and as a soccer fan I would’ve liked to see the importance of the fans in the stadium. But obviously that didn’t turned out. Anyway, fans belong into the stadium and the results just state that the teams are good at adapting when it’s about to get used to new circumstances.
Nevertheless, I’m pretty sure that all sports fans around the globe can’t wait to return to the stadiums, cheering for their teams and getting back to normal.