Posts

Foreign leagues profit from Premier League wealth.

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The UK has long been a country that imports more goods than it exports. For decades we’ve been buying more food, cars, and other consumer goods from the rest of the world than we've sold. We tend to purchase more than we produce, and in recent years this has also become true of another type of commodity: footballers.

EPL clubs are rolling in the money received from the lucrative sale of TV broadcasting rights, sponsorship and match-day revenue. A large proportion of this wealth is being used to buy players for exorbitant transfer fees and service huge wage bills. This season, English clubs have paid nearly €2 billion in transfer fees, of which €1.1 billion has been spent on imported players. Income from player exports is significantly less – €0.4 billion – leaving English clubs with a net overseas expenditure of €0.7 billion: another large trade deficit.

English football has been running a trade deficit for some time. In the last six seasons, clubs have spent a total of €4.6 billi…

Consistent or Calamitous: How good is your goalie?

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David De Gea won the match for Man United at the Emirates last month. Under siege for much of the second half, de Gea’s brilliant performance preserved United’s lead at a crucial stage of the match. He made a total of 14 saves in the match, equaling the EPL record set by Tim Krul for Newcastle in 2013.

How many goals does a high-quality goalkeeper like de Gea save his team over the course of a season? Pundits frequently claim that a goalkeeper is worth so many goals or points, but this has never actually been measured. In this post I take advantage of a novel feature of Stratagem’s dataset to infer the number of goals that EPL goalkeepers have saved or cost their teams in the last two seasons. Who is bailing out their defence, and who is letting them down? Would United be a top-4 team without de Gea? Is either of Mignolet and Karius a decent shot-stopper?

The difficulty of a save
When a goalkeeper fails to make a routine save it is described as an error, costing the team a goal. But …

Hectic xmas schedule gives some teams an artificial advantage

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Earlier this week West Brom made an official complaint to the Premier League regarding the scheduling of their match against West Ham, which took place only 48 hours days after their 1-1 draw against Arsenal. The root of their concern is not that their players had only one full day to recover, but that West Ham did not have the same issue. The Hammers' previous match was on Boxing Day, giving their players an extra 5 days of rest. Despite taking a first half lead West Brom went on to lose the match 2-1.

West Brom clearly feel that five additional days of rest may have given West Ham an edge in what was already an important fixture in the relegation battle. Is there hard evidence to support this? Using historical results, can we demonstrate statistically that one team is at a disadvantage when they play twice in a short period of time and their (second) opponent does not?

Is one full day of rest enough?
I searched for every professional league match in England in which one team we…

Freedom of Movement of Footballers: Brexit and the EPL

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All opinions, analysis and conclusions are my own. All data was obtained from publicly available sources.

On the 29th March 2017 the UK government activated Article 50, initiating a two-year countdown to the UK's departure from the EU. The government has already stated that freedom of movement of people will end in March 2019. From that date onwards, all foreign footballers – regardless of their origin – could require a work permit to sign for a club in the UK. This would have enormous consequences for British clubs and the future of British football.

Over the last 20 years, Freedom of Movement of People (FoM) has transformed English football beyond all recognition. FoM bestows citizens of the European Union (or the wider European Economic Area[1]) with the right to travel, reside and work in any member state. When an English football club decides whether to buy a foreign player it must consider the passports he holds. If the player holds an EU passport then there are no restricti…

Bodies on the Line: Quantifying how defenders affect chances.

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From blogs to the BBC, the concept of ‘expected goals’ has entered the mainstream media's lexicon. It has caught on because it’s a useful concept; it’s a useful concept because football is a low-scoring game. Chance (or luck) can be the difference between victory and defeat, a good day or an off-day. Expected goals, however, measures what would have happened on an average day.

It’s a simple quantity to measure. Shots are assigned a number between the 0 or 1: the proportion of similar shots (from the same position, for example) that have resulted in a goal. I’ll refer to this as ‘chance quality’. You then add up the chance quality for every shot taken by a team in a match to calculate the number of goals that you would have ‘expected’ them to score that day[1].

One problem with typical measures of chance quality is that they tend to ignore the other team. How many of their defenders were between the shot-taker and the goal? How effectively were they denying him the time and space …

From excess to success: Neymar, inflation, and the price of an EPL title.

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Like stock markets in the late nineties, the English transfer market is soaring ever higher. In 2010, EPL clubs spent nearly £500m; in 2014 they broke the £1bn mark and this season total spending should exceed £1.5bn. While the number of transfers each season has risen gradually since 1992, the huge increase in spending has been driven by exponential inflation in transfer fees. In 1993/94, £3.75m was enough to buy one of the best midfielders in the league: Roy Keane. These days, it’s difficult to imagine that sum buying you anything but a budget squad player. A top-class midfielder now costs upwards of £50m, and could easily be significantly more.

Such rapid inflation renders meaningless comparisons of club spending over a long time horizon. £7m is peanuts by today’s standards but was the maximum spent in 1992, in this case by a Jack Walker-funded Blackburn (of which about half went on Alan Shearer). If we want to measure and compare player investment over time we must convert past t…

Pundit Consensus Forecasts

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In my last blog, I demonstrated that the weekly EPL predictions of Mark Lawrenson (for BBC Sport) and Paul Merson (for Sky Sports) consistently beat the betting market. Betting a constant amount on their predictions (home win, away win or draw) over the last 3 years would have resulted in an 8% profit, on average, for both pundits. I also showed that a lot of this performance is down to their ability to predict draws, something that the bookmakers – and most statistical models – are quite poor at doing.

So far I’ve treated Lawrenson and Merson’s predictions separately, but what if we combine them? Can we improve their predictive power? They may feature on rival networks, but in this post I’m going to look at what happens when Merson and Lawrenson work as a team.

Consensus Forecasts
From the 2014/15 season through the 2016/17 season there were 1101 EPL matches for which Merson and Lawrenson both made a prediction. But how frequently did they make the same prediction? The grid in Figure…