Last week I described how exactly I have been gathering xG data for the SPFL with the limited information that is available out there. I then shared the top performers individually in the SPFL in expected goals and discussed if those players were over/underperforming. We can use the same data on a team level and see which teams have been over and underperforming so far this season. We can also explore how St. Johnstone spit in the general direction of the concept of advanced stats and may force Seth at Fitba Fancy Stats  give up on football and focus on fly-fishing analytics.

You can see every team’s xG totals, xG conceded, and xG differential, among other stats on my Advanced Stats Team Table, which is updated weekly. Or just look down an inch.

Advanced Stats Table-2

https://public.tableau.com/views/SPFLAdvancedStatsTable/AdvancedStatsTable?:embed=y&:display_count=yes&:showTabs=y

https://public.tableau.com/views/xGpoints/xGTotalPoints?:embed=y&:display_count=yes&:showTabs=y

When we look at the xG total over points in the table, it should be no surprise to see Celtic far and away the leaders in both categories. Celtic’s chance creation has been great all year and has catapulted them to the top of the table. Surprisingly, the second highest xG total in the SPFL through 15 games has been Ross County. I have waxed on about my admiration for County Striker Liam Boyce, but the whole team has done surprisingly well in creating quality chances for the Staggies. If the Dingwall team can continue to produce offensive chances like they have, they have a strong chance of finishing in the top 6.

At the other end of the table, Inverness CT have really struggled to create chances and their position in the table reflects this. With Ryan Christie heading to Celtic early after an injury and Dani Lopez’s future with the club uncertain after a spitting incident, Caley need to focus on finding someone who can create some chances or they could find themselves fighting relegation either in last place or in the relegation playoff spot. Could this current squad hold off Rangers or Hibs in a playoff? That is probably a gamble the Highlanders do not want to take.

https://public.tableau.com/views/xGConcededpoints/xGConcededPoints?:embed=y&:display_count=yes&:showTabs=y

xG Conceded_Points

On the other end of the field, Celtic and, perhaps surprisingly again, Ross County are among the top xG Conceded teams in the league. Another surprise team at the top of the table, Hearts, owes much of their success to their stout defensive play. With an xG total of 13.01, good for third best in the league, Hearts back line have restricted and frustrated opponents and gotten enough from Juanama up front to stock up points. Hearts have shown that they have what it takes to fight for a European spot all season. With all the financial troubles of the end of the Mad Vlad Romanov, could even the most fervent Hearts supporters picture European football back at Tynecastle next year at the beginning of this season?

https://public.tableau.com/views/xGDifpoints/xGDiffPoints?:embed=y&:display_count=yes&:showTabs=y

xG Diff_Points

Combining xG for and xG against provides us with a chart that resembles the above charts, with many of the same high and low performers in similar spots as they are in the previous charts. I want to take this space to discuss St. Johnstone’s performance thus far in the season. In the table, the Saintees find themselves in fourth place, but only 3 points behind third place Aberdeen. For the longest time, St. Johnstone and Tommy Wright have been the scorn of the Scottish Football analytics community (all five of us), with much of their success reliant on Alan Mannus often pulling 3 points out of a hat. Whatever methods they have used and however unsustainable St. Johnstone’s performance was, it yielded them a Scottish Cup and a few Europa League qualifiers. This season, Mannus has had a decent but not spectacular season, with a save percentage of 68%. St. Johnstone have instead relied on the forever young 33 year old Steven MacLean (mentioned here) and Graham Cummins (quit giggling in the back!) to propel them up the table. The Saintees have a similar xG total and xG conceded totals as Aberdeen, but have one of the lowest Total Shot Ratio and Total Shot on Target Ratios in the league. With such a low amount of shots, one would think that St. Johnstone cannot sustain this success, but then again people have been thinking that for years now.

One thought on “Expected Goal and the SPFL on the Team Level: St. Johnstone Hates You and Your xG Model

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