Last up in this series of reviews covers the second part of the Science + Football conference.
On day 2 of the conference I kept a low profile and stuck to my seat in the presentation theatre for most of the day. It was another day of sessions from a wide variety of speakers (as by now I had become accustomed to) including psychologists, sports scientists, statisticians, scouts and a panel session including former England manager Steve McClaren.
Dr Misia Gervis, who I noted in my earlier review of the Sports Analytics Innovation Summit, gave a presentation which really struck a chord with the post I wrote on Saturday evening. A senior lecturer in sports psychology at Brunel University, Gervis’s talk discussed positive psychology and how it can be applied at football clubs. She is actively involved in efforts to bring psychology into football clubs so that it can be used to benefit players and performance. Actually, in a follow-up to my earlier post, I had already been advised to look into the work of Jacques Crevoisier whose work with the development of psychometric tests for Liverpool and Arsenal has been well-documented (although I didn’t know of him before this tip). Gervis discussed resilience: “the ability to take hard knocks, to weather the storm and to value oneself no matter what happens” – this is affected by fear of failure, perfectionism, injury and criticism with a further impact on emotional control and decision-making. She highlighted the importance of using the concept of ‘signature strengths’ with players, where their best attributes are identified and developed to help create the right conditions for them to flourish.
We were also treated to a couple of lectures about fitness planning and training regimes by Dr Peter Krustrup of the University of Exeter and Matthew Cook, head of sports science for the MCFC academy. Both discussed how optimal fitness training for footballers involves training sessions which mimic the movements and levels of activity in a match. Krustrup included work from one of his studies, showing how yo-yo training (high intensity intermittent exercise) performance was a better indicator of match fitness than VO2 max testing – although there is a correlation for footballers. Cook explained that for academy prospects at Man City, they go so far as to look at the biological age of players vs maturation levels to try to ensure that developing players are not discriminated against in comparison to faster-growing players.
That last point links in nicely with Blake Wooster’s presentation. Wooster, business development director at Prozone, described his role as a kind of coaching scientist. His views represented the future of analysis in sport when he said that clubs should “use analytics to drive and not just inform decision-making”. Wooster’s session tied in with Rasmus Ankersen’s presentation from the day before (and to a lesser degree Cook’s reference to youth maturation) as he discussed the relative age effect in youth team football. He showed how different youth age groups are concentrated towards players born in the months directly following the cut-off point because the oldest boys are likely to be the most developed e.g. where the cut-off is 31 December, players selected in a football team are most likely to be born in January and February. He went on to describe the current Belgium national team, which has an incredibly strong first 11 at the moment, and how in recent years they overhauled their age groups to include 2 separate teams – one ‘A’ team and a development team called “the futures”. Wooster also gave an example of how Prozone calculate expected pass-success rates vs actual success rates to analyse youth players and potentially identify undervalued talent – this for me was a very satisfying use of stats to aid player appraisal. Wooster, however, did admit in the later panel session that analysis is still in an embryonic stage and that the term ‘moneyball’ in football is not particularly useful in selling analytics to clubs.
For what it’s worth, the presentation that I thought was the most interesting and well-measured throughout all of the 30-odd sessions I saw over the 4 day period was from Liverpool’s Director of Research Dr Ian Graham. Graham joined the club in the summer of 2012, following 7 years with a football analysis company. His presentation, entitled “The trouble with statistics” included the right balance of caution, care and logical proofs in answering a simple question: are clean sheets more important than scoring goals?
Graham’s regression analysis showed that one extra goal scored for a team is worth 1.02pts on average, whereas one extra clean sheet is worth an additional 2.99pts. From that piece of information alone I suppose one could be forgiven (if you want to be kind) for thinking that clean sheets are indeed more important than goals scored. But the R-squared of goals scored vs points is 77% whereas for clean sheets vs points it is 65%. The relationship with clean sheets is weaker because of volume – clean sheets are a limited resource whereas goals scored are unlimited in a match. In order to improve from an average level of goals scored (50 per season) to the top quartile you would need to score about 10 more on average (+20%). However in order to go from 11 clean sheets (average) to the top quartile level of 14 per season you need to improve by +27%. Hence we might say it is ‘easier’ to score more goals than to improve clean sheets. Having shown this, Graham explained that the FA really was a pioneer in football in 1980 when it became the first association to introduce 3pts for a win in order to incentivise attacking football (not that it had a major long-term effect). He also discussed the path of strategies for teams at different levels – showing that clean sheets are still relatively more important for below average sides who are less likely to outscore a top team and will have a better chance of success if they restrict their opponents from scoring.
The last session I attended was the coaching panel with Steve McClaren, Paul Holder (FA national coach) and Scott Miller (first-team fitness coach at Fulham). As I noted in my previous post, McClaren began by talking about how great it was to be able to support an exhibition of innovation in football, before saying that “all I want from you science people is fitness and injury stats”! He insisted that management needs be allowed to work on instinct – which just goes to show the reality of the challenge that analytics has to overcome if it will ever become fully integrated at football clubs. He gave some useful insight into his knowledge of the differences in coaching between the Netherlands and England – in the Netherlands it seems that football-related training and fitness training with a ball are given more of an emphasis. McClaren used his experiences from Twente and Wolfsburg to argue that game intelligence in England needs to improve, giving an example of a young player at Twente who, when he was asked his opinion on team tactics for the upcoming game, gave a such a full account of player positioning and where to concentrate attack/defence with a good enough understanding to be one of the coaches.
One of McClaren’s final points was that “coaches go into a comfort zone where they don’t seek to learn more. More coaches should get out of their comfort zone and try to learn new skills and gain knowledge and experience”. Finally a positive from him that could be taken for analytics, although unfortunately he wasn’t talking about the use of performance data by coaches!
I have been quite prolific over the past 7 days in terms of writing and reviewing the conferences and this is for 2 main reasons. Firstly, I have been inspired with ideas and enthusiasm after attending the conferences – for anyone with a serious interest in sports analysis I would definitely recommend getting a ticket for either (or both) next year. Secondly, the readership of my blog has increased well beyond usual levels since I started it about 6 months ago so thank you to everyone who has taken an interest and in particular retweeted/shared the link of my blog to followers, colleagues and friends. My enthusiasm in posting the reviews quickly has meant it has all been a little unfiltered but I have tried my best to keep them as informative as possible!