Scatter graphics: League 1, 20 Oct 2016

Below is the latest refresh of the scatter graphics, each of which is explained briefly below and at length here.

Shot dominance

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).


I was surprised to see Port Vale sitting in the play-off zone given how few shots they’ve taken this season, although the next graphic will shed some light on this.

Another surprise is that MK Dons have been the most dominant team in shot terms, yet currently sit in 16th, which again will become less mysterious in the following graphics.

Surprise number three is that leaders Scunthorpe are slap bang in the middle, rather than the bottom right position that league leaders normally occupy – again the next graphic will help us to understand this.

Attacking effectiveness

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:


Dealing first with the clubs I mentioned above, we can see that Scunthorpe and Port Vale have been the two most clinical finishers so far, which explains how their league position is much higher than the number of shots taken would usually suggest. Whether this is sustainable remains to be seen, but the fourth chart will help us to determine this.

MK Dons’ relative wastefulness has seen their dominance often go unrewarded, although compared to Coventry they don’t really have that much of a problem here.

A rare win for Oldham has improved their standing here slightly, but overall chance creation and conversion remain issues that the Latics need to resolve.

Defensive effectiveness

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 trio in the bottom left – Millwall, MK Dons and Rochdale – have allowed the fewest shots in the division but all have underachieved due to some porous defending. Dale appear to be well on the way to resolving their problems – a 3-0 midweek reverse notwithstanding – and the other two should also be capable of climbing the table if they can plug the leaks.

High above them we find Bradford and Bolton, both of whom look incredibly difficult to break down this season. However a glance back to the previous chart suggests that both have seen defensive solidity come at the cost of a cutting edge up front.

Oldham may have struggled to convert their chances this season but at least they’ve been making life difficult for their opponents too, although it remains to be seen whether the current degree of heroics can be maintained.

Expected goals

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:


Despite trailing in Scunthorpe’s wake so far, Bradford look the likelier of the two to top the division in the long term. For all their goalscoring exploits, the Iron have actually looked more convincing at the back than up front, although the return of Paddy Madden may nudge them rightwards.

Bury remain the division’s most potent attackers so far, although four straight defeats – admittedly against a relatively high standard of opposition – have seen them stutter. Meanwhile on the opposite side the “quality over quantity” argument isn’t washing for Port Vale and it’d be surprising to see them sustain a top six place without some attacking upgrades.

Walsall’s recent upturn in form hasn’t yet been accompanied by them storming away from the undesirable top left corner, with their defence continuing to look vulnerable despite some improved showings in attack.