An updated look at performances in the EPL

During the last international break, we’ve used the lull in club team football to look around the top-5 leagues for some early looks at performances. And it’s international break again, so why not check back with four more match rounds played and see how are estimations have held up so far, making some new predictions to go along with it. Here’s the EPL to start with.

 

Good-Lucky

I’ll plot both Good-Lucky matrices to allow for a quick comparison, on top the chart from the previous piece after seven match rounds, below the updated version with now eleven match rounds played. Generally, over the course of a season we tend to see teams move closer to the red line, indicating average PDO’s in relation to performances as measured by Expected Goals (ExpG) ratio. Last time out, after seven matches, five teams had PDO’s below 950. Four matches later, only Burnley remains that low. Neat phenomenon, that regression towards the mean, isn’t it?

At the top there is some PDO regression too(Leicester, Hull, Spurs), but some PDO’s are moving in the opposite direction. Would that make Southampton fans happy? Well, it’s a mixed bag really. On one hand, this PDO rise will undoubtedly come down over the rest of the season. On the other hand, the points won over the past four matches (four wins, goal tally 12-0) are in the bag and will help propel the team to very firm top-4 candidacy, and even an outside shot at the title. Just don’t count on PDO driven points next season, and enjoy the wave while it lasts!

Good - Lucky Matrix English Premier League 2014-15 14 oktober 2014Good - Lucky Matrix English Premier League 2014-15 17 november 2014

Magic

Please note the top-2 teams in both charts.

Chelsea were early season runners, pairing exceptional performance (ExpG ratio) with very efficient finishing (PDO). Over the past four matches, their ExpG ratio has come down from 0.721 to 0.657. Still good enough to win the league, but no longer that elite to win it without depending on PDO favours a bit.

Meanwhile, Arsenal have moved in the opposite direction from very good to elite (0.730). However, their unkind PDO ride has already cost them a significant amount of points, and even with a return to PDO normality, they probably won’t catch Chelsea with the present twelve points gap. Still, a top-4 spot seems a lock, which may be enough to produce some ‘Arsène managed to turn it around’ or ‘The return of [insert injured player] helped Arsenal back on track’ story somewhere.

Interestingly, Chelsea have not regressed and even maintained their PDO at 1081 and also Arsenal don’t experience a PDO rise as they have stayed at 949. Over the course of the season however, Arsenal will start chipping away points from Chelsea’s 12 points lead. Looking at the end-of-season predictions (see below), we wouldn’t immediately expect the Gunners to overtake the Blues, but with some kind PDO swings, Arsenal may just pull it off and allow magic headlines to appear.

 

Title race

Chelsea still remain hot favourites for the title, with City only just leading the chasing trio. Where the model previously gave Chelsea an 81% chance to win, their stock has now fallen to 58%. Note that Southampton (enjoy the PDO wave while it lasts!) may just have enough to seriously challenge for the title. An 0.632 ExpG ratio team does need a friendly PDO wave to complete that, but hey, it’s not impossible at all.

Boxplot projected League positions - winners English Premier League 2014-15 18 november 2014

Relegation land

In relegation land, we had firmly marked Burnley, Leicester and Hull as relegation candidates last time we looked, with all three of those teams well over 60% odds to go down. Four matches later, things are still very poor at Burnley and Leicester, but slightly less frightening for Hull.

Boxplot projected League positions - relegation English Premier League 2014-15 18 november 2014It’s curious to see how poor the relation is between a low ExpG ratio and relegation odds at the moment. Hull are definitely the worst side in terms of performance as measured by their 0.318 ExpG ratio, but have had a kind PDO wave (1044) that allowed them 11 points already.

The same can be said of Swansea, who’ve enjoyed friendly PDO spells to start the season (1077). That PDO has covered up what has otherwise been a very poor performance (0.386 ExpG ratio). It’s even looking quite possible that Palace, who are ranked 17th with 9 points despite a 0.452 ExpG ratio may overtake Swansea (5th at 18 points) with any decent swing of PDO. I’m not saying it will happen, but just realize how easy swings around mid-table are made in football.

I’ll leave you with an updated version of the points prediction. Looks like the most interesting battles will be for the least interesting positions like for 2nd place and for Europa League qualification…

Boxplot projected league table English Premier League 2014-15 18 november 2014

 

If all these terms are new to you, click here for explanations of Expected Goals and PDO.

4 thoughts on “An updated look at performances in the EPL

  1. Peter

    Great job. Would be cool if you could do something like that for the Bundesliga after the first half of the season is over (which would be after the games next week). Thanks in advance 🙂

    Reply

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