Seems a silly question, right? The final will be at Bayern’s home stadium. But it won’t be full of Bayern’s fans, as it is when they usually play. So are they really going to enjoy the full effects of home advantage?
Home European Cup Finals
There are previous instances of European club finals being played at one of the teams’ home grounds: Madrid won the European Cup “at home” in 56/57, Inter won in 64/65 and Roma lost in 83/84. In the UEFA Cup, Feyenoord won in 01/02, Sporting Lisbon lost in 04/05 and finally in the European Cup Winners Cup Barcelona won in 81/82. Thanks Wikipedia!
So four wins and two losses, that’s exactly what you’d expect with full home advantage in effect and two teams of equal ability. But most of these matches are far in the past: maybe the home teams were strong favourites and maybe the stadia all those years ago really were full of home fans. Is there anything else that can help us?
Home Domestic European Cup Finals
I was surprised to find (thanks again, Wikipedia) that French, Norwegian, Danish and Swedish have been played at club grounds, and there have been many instances of cup finals “at home”.
PSG played in five cup finals at Parc des Princes, winning three, drawing one and losing one after 90 minutes. The Scandinavian teams didn’t do so well in their Cup finals – see the table for more details.
I used our team strength model to predict the average goals scored and conceded in these “home finals” with two assumptions: Either full normal home advantage or no home advantage. I did this because it allowed me to take into account what we expected of the teams in the finals. (Note I couldn’t estimate some of the older finals due to a lack of historic data for older matches – I predicted 19 of the 30 finals.)
The results showed that the finals were more consistent with a neutral home advantage than a full home advantage, but there was a 29% chance of seeing results as poor as those observed if full home advantage was in operation. A suggestive but not conclusive result.
London Clubs at Wembley
So there still isn’t really enough data to say how big the “home cup final” advantage is. Can the FA Cup help us?
London clubs won 11, drawn 8 and lost 5 cup finals at Wembley from 1947 – 2000. The full home advantage assumption is a better fit for London clubs at Wembley (again taking into account team strengths) and it’s quite unlikely that results as good as these would be observed if neutral home advantage was in effect (only a 14% chance). But the observed home advantage is not as big an effect as full home advantage.
Bayern – Chelsea
So domestic cup finals say we should assume a neutral ground, London club Wembley finals say we should use a reduced home advantage, and Bayern would like to think they have full home advantage. Here’s the prediction, for a range of home advantage scenarios:
Is there any other data we can use to improve our prediction? A quick scan of the academic literature suggests that distance from home ground, fan composition, referee bias and many other factors may be important. All suggestions welcome!