Ahead of our 'Football and Data' event on Thursday 9th March, we spoke with Professor David Sumpter Professor of Applied Mathematics Uppsala University, Sweden about the launch of the paperback version of Soccermatics, and his background in data and analysis.
In the day job what does a typical day involve?
Until recently it involved running a research group of about 10 PhD students and other researchers interesting in modelling social behaviour of animals and humans. I think I have the most brilliant job in the world. We look at so many interesting problems, such as how fish escape predators, how ants build trail networks, how heavy metal fans build mosh pits and audiences applause, and many more (See www.collective-behavior.com). I work with a great bunch of people. They come in my office, discuss problems with me, go out and work hard on finding answers.
I say, ‘until recently’, because more and more of the interesting problems have become football problems. Now I have the same type of interactions with football app developers, analysts and journalists. Its very much the same type of highly interactive work.
I also have teaching, which I enjoy. I’ll be teaching probability from next week. There will be lots of football examples in the course!
For any data analysis, what kind of tools are you using?
I use Matlab mostly. Its what I learnt when I was a student and it has stuck. Its easy because I know it. But I also use R and Python if I use data from an API, and its these two which I would recommend for people starting out in this area. Matlab is proprietary software and goes against the spirit of things.
But to do data analysis properly, you do need to use a programming language like these, with good data analysis tools and good graphical displays.
For online visualisations d3js is a great thing. But I haven’t mastered it yet.
Did you always know you'd end up in academia (and are there any differences working in Sweden)?
No. I knew I would go to University but I had no idea why, other than my parents told me I should go and I was good at school. Then I got there and I thought, “this is great”. And wanted to stay. When it is at its best, a career in academia is hard to beat. You get time and space to develop your ideas.
I moved to Sweden mainly because I fell in love with my wife. It is a good place to raise a family. I could go on parental leave for long periods with both my children. So the big difference in Sweden is the work/life balance. It’s a bit more healthy here.
How did you first get in to analysing data in football?
It was through my son’s interest in the game that I first started thinking about it in mathematical terms. I started coaching his team and thinking about how to talk to them about movement and positioning. Maths is a big part of this.
The key idea behind Soccermatics is that maths can be used in all sorts of different ways: not just in football but in modelling different systems. I had this idea very early and told a literary agent, Chris Wellbelove, about it. He was like “Yeah thats interesting but theres too many animals and stuff like that in what you’ve written….but that bit you wrote about football, can’t we have more of that!”. And thats what happened. He was right. There was load of maths in football. The original version of the book was 3/5ths football and 2/5ths other systems (ant trails, fish schools, human crowds, sexual networks etc…).
The Pro Edition includes even more football. The more I’ve worked with this, the more interesting things I’ve found to analyse.
What was the reaction to the Hardback version of the book?
What has been most amazing for me personally is when someone writes to me and says they have read the book and been inspired in some way.
I have had feedback from all different types of people: 18-year-olds who say I’ve read your book and are going to University to study maths; science nerds who tell me that they now realise that football is actually an interesting sport; senior academics who ring me on my work phone to comment various sections and give constructive criticisms; parents who have bought it for their football mad sons or daughters; scouts and analysts at clubs who want to find ways they can use Soccermatics in their work; amateur analysts with technical questions on Twitter….
The list just goes on and on.
The book has sold well, and my publishers are happy. But it’s the feedback is really what I enjoy most. Interacting with people. It can be difficult to keep up, but I try to reply to every comment or query I get.
There's quite a bit of talk about role of analysts at clubs e.g., The Secret Analyst do you think someone wanting to work within Performance Analysis/Analytics doing a non-Sports related course then moving in to it after graduating?
Yes. I think if you have the analytical skills take courses in maths, economics, stats, computing etc., while taking coaching badges in your spare time. This gives you better options for two reasons. Firstly, the quantitative skills are harder (although not impossible) to pick up later. Secondly, when you have finished studying maths or a similar subject, you’ll have skills that lead in to a wide range of jobs, not just in football. Maths can be used everywhere.
The audience for your work may have a range of analytical knowledge/degree of comfort with numbers, how do you tailor your output to ensue you get the message across?
I make a lot of effort to tailor what I write to the audience.
I have worked with quite a few newspapers and football magazines. Journalists are under pressure to have an angle: Ranieri’s sacking, Zlatan’s shooting, best player in the world and so on. When I am asked to help with these, what I try to do is add a bit of data and understanding to the story, but it is difficult to go very deep. Its something I accept. We have to remember that football is a form of entertainment, its not an excuse to give a maths lesson or a lecture in tactics. So I always tailor for what I am asked for.
But I also try to go in to more depth in other forums. That was part of the reason for the ‘Pro Edition’. I had a chance to go in to more depth in to what real analysts do. I have also tried to do the same in my online series on Medium/Nordic Bet. I look at the ideas in more depth. When Nordic Bet asked me to write something “as geek as you like”. Its the same with Bloomsbury, the book publisher. I can write what I want to, and that is lots of fun and why I write books.
Any recommended sites/books/podcasts to help someone be a better analyst?
Statsbomb is obviously the best site if you want proper, detailed analysis based on data. They are in a league of their own. Sites run by Statsbomb contributors also tend to be good. If you find someone on Statsbomb then go in and look at their personal site. You’ll find lots of good stuff.
There are lots of good tactics blogs too. I was lucky enough to have an extensive conversation, during the writing with Reni Maric about the geometry of the game. Until I talked to him, I thought I knew a lot about the geometry of the game, but I soon realised how much planning is required over the whole field. Start with his articles. They are brilliant.