In the lead up to the start of Eliteserien on 1st April we’ll be looking at some of the numbers that shaped last season, especially the difference between Expected Goal (xG) and actual goals scored and conceded.
Using Stratabet’s chance classification and conversion rates (in addition to a xG of 0.84 for penalties, based on data from last season in Eliteserien), we’ve summed up the xG for and against for each team, comparing the difference with their actually goal difference to see if there were any teams that had significantly under- or over-performed in terms of goals and results last season.
(Note: ‘over-performing’ offensively might of course indicate having players with very good finishing skills, but even a casual analysis of Eliteserien strikers would find that quite unlikely. It’s a very even league – with an obvious exception at the very top and bottom last season – so even any moderate outliners are highly likely down to random and unsustainable variation).
This is how Eliteserien 2016 looks in terms of the relationship between xG difference and goal difference:
Eyes are immediately drawn to the top left corner, where Brann and Stabæk resides. Brann’s goal difference is +15 compared to a xG difference of only +1.97. The majority of the difference is defensively, Brann’s expected goals against being 7.5 higher than the 27 goals they actually did concede. Quick conclusion; unless notable improvement this season, Brann is very unlikely to repeat their surprising second place this year.
Similar fate might await Stabæk, who only avoided relegation by one point last season, securing their place in Eliteserien after a play-off win over Jerv. The difference between their xG and Goals from last season is a quite exceptional 14.2. Again, it’s defensively that the ball has seemingly rolled their way more than can be reasonable expected, conceding 42 goals compared to the 51.5 expected goals. It’s unlikely that they’ll get the benefit of such a variant again and their underlying numbers would need to improve if they are to survive another season.
Looking elsewhere, there isn’t much comfort for any team wanting to challenge Rosenborg this season. Even though they won the league by 15 points and only lost one of their first 27 games, Rosenborg still slightly underperformed at both end of the fields, their actual goal difference 3 goals worse than their xG difference.
A lot is expected of Vålerenga this season with Ronny Deila taking charge of his first full season at the club. Fighting relegation for most of the season, a strong finish saw them end up in 10th place in the end, but even that is far below the expected standard. The numbers indicate that it was fully deserved; their xG difference was actually the fifth highest in the league in terms of overperforming, at +3.4. Deila will have his work cut out to improve Vålerenga this season, a team that was just as bad as the results indicated.
Spare a thought for Start – they were almost a laughing stock last season, going over 14 months between league wins and amassing a paltry 16 points, 15 adrift from safe ground. The xG numbers shows that while they were obviously not playing great, they weren’t as bad as their actual results. In fact, their xG difference is 14 goals better than their actual goal difference, almost twice as much as the team that ranks second in terms of underperformance, Sarpsborg (-7.4).
If Sarpsborg keep producing the chances they did last season, expect to see an improvement in their already credible 6th place – they scored almost 11 goals less than what was expected.
It’s worth mentioning Ian Burchnall’s Viking as well. While they over performed slightly defensively, they rank third in terms of underperformance offensively, with 6.3 goals less than expected. While the money available in Stavanger is sparse, there is plenty of room of ‘easy’ improvement if their offensive variances just return to the norm.
This article was written with the aid of StrataData, which is property of Stratagem Technologies. StrataData powers the StrataBet Sports Trading Platform, in addition to StrataBet Premium Recommendations.