Posts

Showing posts from 2016

Does January transfer spending improve results?

Image
Last week the Sunderland chief executive, Martin Bain, warned that only "very limited" funds will be made available to David Moyes in the January transfer window (see here, here and here). Bain said that Sunderland are “not going to be able to spend to get out of trouble” and that "we have reached a point where there has to be a time where you don’t have that short-term hit to plug the holes in the dam".

The implication is that Sunderland have put their long-term financial health at risk in previous seasons by spending substantial sums in January in a last-ditch effort to retain their EPL status. While they have indeed survived their recent flirtations with relegation, is there any compelling evidence that winter spending actually improves results in the second half of the season? By out-spending their rivals, are troubled teams boosting their chances of staying up, or are they just using up previous financial resource that could be invested more carefully in their…

Playing in Europe does affect domestic results in the EPL

Image
There’s recently been a bit of discussion in the media (e.g: Sky, Guardian) on whether participation in European competitions has a negative impact on an EPL club’s domestic performance. This is partly motivated by the significant improvements shown by Liverpool and Chelsea this season: after 13 games they are 10 and 17 points better off than at the same stage last season, respectively. Neither are playing in Europe this year. Leicester are demonstrating a similar trait, albeit in the opposite direction: they are now 15 points worse off than last season. For them, the Champions League seems to have been a significant distraction.

Numerous studies have demonstrated that there is no ‘hangover’ effect (see here and here) from playing in Europe. There is no evidence that EPL teams consistently perform worse in league matches that immediately follow a midweek European fixture. But what about the longer-term impact? Perhaps the mental and physical exertion of playing against the best teams …

Final Table Predictions for the EPL

Image
In a previous post I looked at how the EPL league table evolves over a season, showing that we already have a decent idea of how the final league table will look after just a third of the season.

I’ve now taken that analysis a step further and built a simple model for predicting the total number of points each team will accumulate over the season (and therefore their final rankings). What follows is a short summary of how the model works; I've provided more technical detail at the end.

Season simulations
Each team starts with their current points total. I then work my way through the fixture schedule (currently 260 matches), simulating the outcome of each game. Results are generated based on the Elo rankings of each team – which I update after each simulated match – and the benefits of home advantage (scroll down to the last section for more details). At the end of the ‘season’, I tally up the final points totals for each team.

This process is repeated 10,000 times to evaluate th…

Elo Impact: Who are the EPL’s most effective managers?

Image
Manager rivalry is one of the big themes of the season. Many of Europe’s most successful managers have converged on the EPL, sparking renewed and fierce competition between England’s biggest clubs as they battle on the pitch to achieve domestic superiority.  In the background there is another competition, one of a more individual nature. Guardiola, Mourinho, Conte and Klopp are seeking to establish themselves as the pre-eminent manager of their generation. As touchline galacticos, their rivalry mirrors that of Europe’s top players.

Success is often measured relative to expectation. Second place this season would probably be seen as a good finish for Liverpool, but not Man City. So Klopp and Guardiola will be judged against different standards. If Moyes guides Sunderland to a top ten finish he’ll win manager of the season.

For the same reason, it’s difficult to compare their track records. A manager may have won an armful of medals, but was it the result of years of sustained improveme…

Wenger's Winter Curse

Image
Halloween may have passed but Arsenal's fans will remain fearful throughout November. This is the month where, historically, Wenger's team have tended to perform significantly below par. Since Wenger took charge in 1997, Arsenal have collected an average of 1.6 points per game in November, compared to a season average of 2 points per game.

In fact, as the figure below demonstrates, Arsenal don't really recover until mid-December. The thin blue line shows the average number of points that Wenger's Arsenal collect in each gameweek of the season; the dashed blue line shows a 3-game moving average. The Nov/Dec curse is clearly visible[1].

For comparison, I've also plotted the same results for Man United under Ferguson. For both teams, I used data from the seasons 97/98-12/13, the period in which the two managers overlap.


It's interesting to compare the seasonal performance of the two managers. In the first and final thirds of the season, Wenger's points-per-gam…

Leagues within a League: How the EPL Table Evolves

Image
We’re nearly a quarter of the way through the EPL season and the league already has a familiar feel to it. Manchester City are top, Arsenal are above Spurs, and Sunderland anchor the table having failed to win a single game so far. There is clearly a lot of football still to be played, but does the table already resemble how it’ll look come the end of May?

Conventional wisdom tells us that the turn of the year is a crucial period. By the beginning of January we are supposed to have a good idea of how things are shaping up. In 9 of the last 20 EPL seasons, the team that was top at January went on to win the league. 56% of teams in the bottom three on new year’s day will be relegated. However, you get pretty much the same results if you measure these stats at the beginning of December or the beginning of February, so perhaps we don’t learn that much over the Christmas period after all.

In this post I’m going to look back over the last 20 seasons to investigate how the league table actua…

Forecasting Football: a hedgehog amongst the foxes.

Image
“I never make predictions and I never will.” – Paul Gascoigne

For football fans, making predictions is half the fun. It’s also big business: the global sports betting market is estimated to be worth roughly half a trillion pounds, and 70% of the trade is thought to come from football.

We all make predictions, but some of us are better than others. In his book, The Signal and the Noise, Nate Silver describes two categories of predictor: hedgehogs and foxes[1]. Hedgehogs tend to have strong pre-conceived notions of how the future will pan out, a view of the natural order of things that they can be reluctant to change. They are confident and assertive. Foxes, on the other hand, are not anchored to a particular world-view: they are more willing to change their position as new information arrives. Foxes try to weigh up all the available evidence; often their predictions are probabilistic in nature.

In football, TV pundits are hedgehogs: ex-players and managers chosen to provide us with the…

The managerial merry-go-round spins ever faster

Image
We’re less than a quarter of the way into the season and the great managerial merry-go-round has already shed its first passengers. Swansea City's former manager Francesco Guidolin was the EPL’s first casualty and five EFL managers have been relieved of their duties. Sam Allardyce, the now former England manager, also terminated his contract last week following a Daily Telegraph investigation into his conduct.

Guidolin was Swansea’s manager for only 259 days. Roberto Di Matteo was removed as Aston Villa’s manager after 121 days. The longest serving of the recently departed was Tony Mowbray, who lasted under two years at Coventry City. Over the course of last season 58 managers were fired; the season before that it was 47.

It certainly feels like managerial tenures are getting shorter and shorter, but is this part of a long-term trend or a recent phenomenon of the money-spinning era? And does it really make much sense to frequently change manager?

Diminishing patience, at all level…

English Hares and Italian Tortoises: When do Goal-scorers peak?

Image
Yesterday, I walked into a New York bar just in time to see Francesco Totti wheel away in celebration. He had just sent Torino's goalkeeper Joe Hart the wrong way from the penalty spot to score his 250th Serie A goal. Totti has scored more Serie A goals than any other player in the last sixty years. He has also now scored in 23 consecutive Serie A seasons.  He turns 40 on Wednesday.

An interesting feature of Totti’s career is that he scored nearly half of his goals since he turned thirty. He didn’t even really get going until his late twenties, a slow burner. Contrast this with Wayne Rooney: 173 EPL goals so far, half of which were achieved by the age of 24. A fixture in the Man Utd team since the age of 18, he is now, at 30, perceived to be much a diminished force.

So when do strikers normally reach their goal scoring peak, and how rapidly do they decline thereafter? Do the hares that establish themselves early in their career tend to burn out faster than the tortoises that have …

The Decline of English Players Abroad

Image
The English national team hit an all-time low in 2016. After being humiliated by the mighty Iceland in Euro 2016, England fans must look back wistfully on the days when pundits would forecast that they would be “knocked-out by the first decent team that they meet”; it seems that these days England struggle to progress far enough to meet a decent team. You have to go back to 2002 to find the last time England beat one of the world’s top ten teams in a major international tournament.

A lot has been written about the impact of the EPL, in particular the proliferation of foreign players and the resulting difficulties faced by talented young English players to get playing time. On average, less than a third of the players starting games are English; 25 years ago, in the first year of the EPL, it was more than two thirds. However, while England certainly has the lowest fraction of home-grown players in Europe’s top-5 leagues, Italy and Germany (both around a half) are not much further ahea…