Scatter graphics: Premier League, 2016/17
Now that the season is over here’s a final version of the scatter graphics, each of which is explained briefly below and at length here.
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).
Five clubs stand out as more dominant than the rest, with Liverpool and Man City narrowly leading the way. Arsenal are some way behind, with their balance of chances created and allowed closer to Southampton.
Burnley look to have done well to survive, having allowed more shots at their goal than anyone except Sunderland and creating fewer chances than everyone except the Black Cats and Middlesbrough.
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:
Three teams stand out as having very little luck in front of goal: the relegated duo of Middlesbrough and Sunderland – with both also struggling to create chances – and Southampton.
The Saints were out-produced only by the top six, but needed over 13 attempts to find the net on average compared with between 7 and 8 for the top five clubs. Man Utd also found it difficult to convert their chances this season.
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 defences of Tottenham and Man Utd led the way this season – both allowing fewer than 10 chances per game and soaking up just over 13 and 12 for each goal conceded respectively.
Burnley‘s back line was also pretty resilient – just a shade less so than United’s – which goes some way towards explaining how they kept themselves afloat despite allowing over 17 shots per match on average.
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:
Man City looked to be narrowly the best side in chance creation terms, with Arsenal again looking some way short of the rest of the top six. However the Gunners’ attack looks better now that we’ve adjusted for chance quality – it’s their defence that seems to need more work.
Interestingly Burnley and Sunderland look equally poor by this measure, so the Clarets may decide to do a bit of remodelling over the summer.