The Stat Man: How are Sunderland looking two games in?

It feels like a lifetime since I had reason to wipe down the nerdy spectacles and get stuck into some football numbers. But finally, after Sunderland’s longest break from competitive football since 1945, the lads are back in action and I’m back to present some alternative views of their performance, based on the numbers.

In an advance from last season, I’ve moved on from using the promotion and relegation ellipses - which demonstrated that we simply didn’t have enough for automatic promotion - to something altogether new and, I hope, more informative.

I begin by looking at League One automatic promotions of the last few years before visualising where Sunderland went wrong in their efforts. Then finally I assess how the 2020-21 season looks so far.

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How To Do Automatic Promotion Things

What better way is there to learn how to do automatic promotion from League One than to have a close look at those who have done it before?

There is much to be discovered in what the numbers generated by Wigan (twice), Burton, Sheffield Utd, Bolton, Blackburn, Luton and Barnsley tell us (I’m leaving Coventry and Rotherham out because that wasn’t a proper season as far I’m concerned).

No less than 235 attributes of performance were examined to determine which really matter. They all tell us something and are important in some context, but the need was to reduce that 235 to a subset of performance attributes that best predicted a League One automatic promotion side. What was left after this process were 24 variables, divided approximately evenly between the offensive and defensive side of performance.

They are shown in the table below.

Now let’s take a look at how each automatically promoted side of the last few seasons performed on these measures using some visualisations.

Numbers are nice, but pictures are better.

We’ll begin with the 2018-19 season.

Each segment around the perimeter represents one of the attributes listed in the earlier table. The offensive attributes are bordered with green and the defensive attributes, red.

There are three circles towards the centre. From the inside out, they are the 10th percentile (red), the median (white) and the 90th percentile (green). The distance each ‘slice’ of black extends out from the centre represents where the side in question rank for that attribute.

If the black ‘slice’ extends beyond the 90th percentile green circle, the relevant outer segment is coloured either green for offensive attributes, or red for defensive attributes.

A segment being filled with either green or red is equally good.

If using this as a quick visual, you can interpret it as ‘lots of black, green and red is good’, and ‘lots of white and grey is bad’.

I’ll spare you too much explanation of the detail and save that for future weeks. What I want you to take away from this, just for now, is that both Luton and Barnsley have ‘lots of black, green and red’.

Next we’ll take a look at the two sides successful in getting automatic promotion in the 2017-18 season.

Both did well but Wigan’s result is particularly impressive (a fact that is clear from the almost entirely black centre).

The 2016-17 promotion winners performed as follows.

Sheffield United’s performance is on a par with that of Barnsley in the 2018-19 season. But Bolton provide a slightly unusual result. Phil Parkinson’s side were above average at almost everything, yet outstanding at very little. This comes across in the plot as being a healthy amount of black but very little green or red.

Finally, we’ll go back to the 2015-16 season.

Wigan’s promotion performance was not quite as impressive as their 2017-18 effort, but it was good enough to get the job done. Burton were rather strange in that they achieved promotion despite only scoring a mid table number of goals while keeping the opposition out at the other end.

Evidently effective, but probably not fun to watch.

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Sunderland’s Past Failures

We know only too well that Sunderland weren’t good enough for automatic promotion in the previous two seasons.

Who knows what might have happened had the season just gone been allowed to complete. Maybe one of the automatic spots would have had our name on it. But if I’m being honest with you, I really don’t think so.

Here is what those two failed promotion attempts look like in plots.

The 2018/19 season had play-offs written all over it. If you look back to the plots above showing Luton and Barnsley’s performances from the same season, it’s quite easy to see why we could never quite get into the top two. We were above average at most things but not great at anything.

Things look significantly different in 2019-20. We were outstanding on the red side of the plot that represents defensive performance. And there were even some outstanding aspects of our offensive game, as can be seen by the presence of some green. However, crucially, the number of shots on target were at relegation levels and consequently the number of goals scored was too low to ever be a realistic automatic promotion contender.

A lack of shots on target and an over reliance on ‘moments of quality’ to get the goals is something I have consistently cited as being a major part of Sunderland’s problems. This was especially the case last season.

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The 2020-21 Season So Far

Before I go on, I want to say that it’s far too early to make any kind of solid judgement about the performance of any League One side.

You, the reader, know that as well as I do.

With that in mind, let’s have a little nerdy fun anyway.

Here is how every side in League One looks so far this season.

The names of the teams above each plot are difficult to read, so I have highlighted Sunderland with white text over a red background (third from the right on the bottom row).

As we have learned, lots of black, green and red is good while white and grey is not. The sides with the healthiest plots are Blackpool, Hull City, Ipswich Town and Sunderland. Bristol Rovers (third from the right on the top row) look poor.

As well as these plots, a single number can be generated based on the same information. That number scores the automatic promotion ‘worthiness’ of each side based on how they have performed to date this season. It can also be used to score performances in individual games and that is something I intend to do in coming weeks.

After two rounds of games, this is how the ‘promotion worthiness’ table looks.

This table doesn’t align with the current league table but I wouldn’t expect it to. This early in the season there are too few games, hence randomness and luck have a large influence. There is also imbalance present - teams haven’t all played each other and some sides have played two tough opponents while others have had it easier.

So it’s important to not read too much into this just yet. As the season unfolds, the interpretations and extrapolations will become more solid. And the above table will align more with the actual league table. But for now, let’s rejoice in - what the numbers are telling us is - a solid start to the season. A start in which our performances have been better than any other League One side, albeit against seemingly poor opposition.

The most pleasing thing for me thus far is that Sunderland have averaged 6.0 shots on target per game to the opposition’s 1.5. Those are automatic promotion numbers.