A couple of weeks ago Constantinos Chappas asked on twitter for predictions for the results of the remaining season of English Premier League:
Football modellers out there: would you be interested in participating in a "poll of models" with end-of-season probabilities for EPL? (1/5)
— Constantinos Chappas (@cchappas) 30. desember 2015
I had been thinking about posting some predictions about the Premier League around new years, since this season is really exciting and it would be a great opportunity to see how well my models would cope with everything that is currently going on. I have never posted any predictions before, so this will surely be an interesting experience. And I thought Chappas’ initiative was really interesting, so that surely gave me a nice reason to come trough.
Today Chappas posted the combined results from all 15 participants so I thought I could share some of the details behind my contribution.
I originally wanted to use the Conway-Maxwell model I have written about recently, but I had some problems with the estimation procedure, so I instead used a classic Poisson model. I used data on Premier League and Championship results going back to the 2011-12 season. By including data from the Champoionship I hope to get better predictions, like I have demonstrated before. Since I used data from a long time back I used the Dixon-Coles weighting scheme, which make more recent games have a greater impact on the predictions. The weighting parameter \(\xi\) was set to 0.0019, which gives a bit more weight on more recent games than the 0.0018 I found to be most optimal earlier.
I fitted the model and calculated the probabilities for the remaining games of the season. From these probabilities I simulated the rest of the season ten thousand times. From these simulations we can get the probabilities and expectations for the end of season results.
So how do I predict the league table will look like at the end of the season?
|West Bromwich Albion||45.8|
Although I predict 0.2 points more for Manchester City than Arsenal, the probabilities for both of them to win is 47.0%. I also give Tottenham a 2.3% chance, Leicester 2.1% and Manchester United a 1.5%. At last, Liverpool have a 0.1% chance. The other teams have a chance less than 0.04%.
I will come back with an update with my entire table with probabilities for all positions for all teams.