E Ratings update: Championship, 2 Oct 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 – have 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.

2016-10-02-ch-sparklines

Having scraped past Sheffield Wednesday in unconvincing fashion, Brighton‘s ratings suffered a wobble which perfectly illustrates how the E Ratings model values performances above results. Newcastle could well overtake them thanks to some strong recent showings; particularly up front where they’ve found another gear lately.

Birmingham and Leeds have both seen their stock rise lately, with Blackburn and Ipswich the biggest movers in the opposite direction. Modest defensive improvements aren’t sufficient compensation for the Tractor Boys’ bluntness in attack and with four successive blanks drawn a change of approach looks necessary.

Poor Rotherham are the worst-rated side by quite some distance and their fortunes continue to decline. Improvements can’t come quickly enough if they’re to preserve their Championship status this season.

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:

2016-10-02-ch-probabilities

Newcastle and Brighton are neck-and-neck as promotion favourites: the Magpies are marginally more likely to finish in the top two but also to finish outside the top six. While this apparent contradiction could just be a quirk that would disappear if I ran more simulations (although I run plenty), this sort of thing happened a few times last season when one team’s remaining matches had a greater difference between “upside” and “downside” than the other’s. I’ll keep an eye on it.

The model still fancies Derby to recover from their poor start and challenge for a play-off place, based on how tough they’ve looked in defence and the way it treats teams whose results are heavily influenced by shot conversion. While the Rams’ attack has definitely gotten worse this season, a shot conversion rate as low as theirs is far more likely to be luck-driven than talent-driven. The E Ratings do factor this sort of thing in, but it takes a sustained run of above or below-average finishing to budge them significantly, lest they over-react to a temporary blip.

At the bottom, Rotherham‘s chances of dropping into League 1 increased further this week and are approaching 90%, which is ridiculously high at this early stage of the season. Obviously they’ll drop relatively quickly if the Millers start winning games, but their extremely poor rating means that the model will be taking a pessimistic view of their prospects for some time to come.