E Ratings update: Championship, 26 Nov 2016

Here is the latest update of the season to the E Ratings and how they predict the rest of the season will pan out. The rating system is explained here, but in a nutshell it’s based on the combined quality of chances that clubs create and allow, rather than their results.

The attack rating broadly equates to how many goals’ worth of chances a team would create against an average opponent (so higher is better), with the defence rating equivalent to the chances they’d be expected to allow (so lower is better). The overall rating is the difference between the two – effectively the average expected goal difference per match – so a positive number is good and a negative one is bad.

The graphic below lists each club in descending order of their overall E Rating and shows how this – along with their individual attack and defence ratings – has changed over the past 30 league matches. The red and green arrows indicate how the overall rankings have moved in the past month and the numbers in brackets show the ranks for each team’s attack and defence ratings.

ch-sparklines-2016-11-26

You can see how each match played out here.

The four best-rated sides look significantly ahead of the rest, with Newcastle still top of the pile – they performed well in their defeat to Blackburn so the model didn’t penalise them.

Ipswich were the only team to move more than one place, rising two after their convincing win over QPR, who they now sit alongside.

The elephant in the room is how much the model continues to look down its nose at Reading (and to a lesser extent Birmingham). These two clubs have been awarded the most penalties in the division (9 and 7 respectively, compared to an average of just 2.5), which tends not to be sustainable and the model dilutes their impact accordingly, so that’s suppressing their attack ratings. The Royals in particular could be more vulnerable in defence than they appear: they’ve conceded around 75% of the goals the model would expect, so either something is going on that the shot data isn’t measuring or they’ve been riding their luck a bit. Time will tell I suppose.

Predicting the rest of the season

Below I’ve used each club’s current ratings and those of their remaining opponents to predict how the rest of the season could play out. Each of the remaining fixtures has been simulated thousands of times, using the current E Ratings to generate probabilities for where each club will finish.

This graphic shows the cumulative probability of where each club could end up, in descending order of average points won. You can think of the ordering of the teams down the left hand side as a “best guess” of the final league table, with the coloured bars showing the relative likelihood of each club ending up in a certain section of the table:

ch-probabilities-2016-11-26

Newcastle and Brighton remain in control of the two automatic promotion places as things stand – it’d take a big swing to depose one of them. Depsite sitting 7th and 9th respectively, Sheffield Wednesday and Derby are the only other clubs the model deems to have a better than 50% chance of finishing in the play-offs, thanks to their strong ratings.

While the model may be suspicious of Reading‘s true level, the gap between the Royals and a more modest placing in the ratings table isn’t huge and their results so far mean that they’re likely to remain in the – admittedly wide – field of play-off challengers.

Rotherham continue to look as doomed as you’d expect, with Wigan‘s chances of joining them in League 1 next season not far off 50:50, but the relegation battle otherwise looks pretty wide open.

What’s changed?

As the graph above only gives the latest snapshot, I wanted to show what effect the latest round of matches has had on the bigger picture. Below I’ve added a few simple graphics to show how the promotion and relegation contests have changed since the previous round of games.

First of all, let’s look at the automatic promotion race. The filled green bars are the current probabilities (and should match the greenest bars above), with the hollow bars showing how each team’s chances looked after the last previous of games.

ch-promotion-2016-11-26

 

Newcastle’s defeat has unsurprisingly nudged their prospects slightly downwards, with Brighton the chief beneficiaries. However the slim hopes of Sheffield Wednesday and Derby of barging into the top two were given a boost as both won at the weekend.

Norwich – defeated by the Rams – slipped down the pecking order and could fall further behind if Huddersfield record a win at home to Wigan on Monday.

Now let’s look at the relegation battle:

ch-relegation-2016-11-26

Blackburn’s win makes life more difficult for Rotherham and Wigan, although if the Latics can stun Huddersfield on Monday then they could reverse some of the damage.

Cardiff’s form has remained unsteady and their loss at Villa dragged them back towards danger, but there’s very little separating the “long tail” of potential relegation candidates at the moment.