Scatter graphics: Premier League, 8 Oct 2018
Given that we’re heading into an international break, I thought it was worth taking an early look at how the Premier League’s clubs are shaping up so far using my scatter graphics These compare the attacking and defensive performances of every team in a division. Each of the four graphics is explained briefly below and at length here.
It’s worth bearing in mind that the fixture schedule can still have a meaningful impact at this point i.e. teams who have had unusually easy or tough matches so far may move quite a bit as the season unfolds and things even out.
First of all, here is how the number of shots taken by each club compares with those they face in return. The average number of shots taken per match is on the horizontal and the average number faced is on the vertical, so bottom right (take plenty, allow few in return) is good while top left (take few, allow plenty) is bad. The stripes are like contours: the greener the stripe, the better the performance (and vice versa for red).
Man City have once again been utterly dominant, creating over three times as many chances as their opponents so far, with both Liverpool and Chelsea deserving a mention for out-shooting their opponents by around two to one.
This is the opposite of Burnley, who have allowed more than twice as many shots as they’ve taken themselves, while Brighton and Huddersfield have been similarly dominated so far.
Fulham and Southampton games have been the most entertaining for neutrals, with plenty of shots raining in at both ends of the pitch.
Now let’s look at attacking alone. The horizontal axis stays the same as in the graphic above, but now the vertical shows the average number of shots needed to score each league goal. Therefore bottom right is good (taking lots of shots and needing fewer efforts to convert) and top left is bad:
Four clubs stand out as having had rotten luck in front of goal: Cardiff, Crystal Palace, Huddersfield and Southampton have all needed at least double the number of attempts to score each of their goals as the average team, which in the Saints’ case is particularly frustrating given that they’ve created an impressively high number of chances.
Arsenal‘s output looks pretty average in raw shot terms, but they’ve been the division’s most clinical team in front of goal (as their weekend rampage at Craven Cottage demonstrated). Bournemouth have also benefited from some sharp finishing so far.
Next let’s look at the defensive situation – basically take the above chart and replace the word “taken” for “faced” on both axes. Now top left is good – facing fewer shots and able to soak up more per goal conceded – and bottom right is bad:
The 0-0 draw between Liverpool and Man City this weekend continued both sides’ impressive defensive records this season, with each having soaked up plenty of shots for each goal conceded and not exactly being loose at the back to begin with.
Wolves warrant a mention for their impressive defensive performance so far – similar to that of established top six sides Chelsea and Tottenham – with their fellow promoted sides Cardiff and Fulham among the leakiest in the division.
However it’s Man Utd whose defence has been the most porous of all, with fewer than six shots faced for each goal conceded: a far cry from their ridiculous resilience last season.
Finally here’s an attempt at correcting the first graphic for the quality of chances created and allowed, using the same “expected goals” values that power my shot timelines (explained here). The reason for doing this is that the results tend to correlate more strongly with performance than when we treat all shots equally:
When we adjust for chance quality the bottom right corner remains pretty similar to the first chart: Man City are again setting the standard, with not much between their closest challengers Liverpool and Chelsea.
Bournemouth are keeping up with the likes of Man Utd and Tottenham, while Arsenal have looked slightly off the pace so far. It’s hard to tell how much the Gunners’ tough opening matches might have affected them, but it remains early days either way.
A few of the teams in the worrying top left of the chart may also be affected by a tough start – for example Newcastle have already played five of the ‘big six’ while Brighton, Cardiff and West Ham have played four each – so it’s still a bit early to call who is set for a relegation battle.