Data Rant: creative performance vs. league position
Even the very best teams are occasionally beaten by a less able side – shock results are part of football’s fabric – but consecutive draws and losses become alarming for any club. Under David Moyes Manchester United endured four such ‘poor streaks’, averaging 2.75 losses and/or draws across the quartet of disappointing runs.
Yet, the data shows that it is far too simplistic to blame ephemeral ‘form’ alone – the cause is more nuanced and rooted in the relationship between individual and team performance. Figure 1, below, compares each Premier League club’s total number of poor streaks to league position. The correlation is strong yet predictable – the team that loses and draws the least will, of course, win the title.
The streaks themselves tell an interesting tale. Stoke City, for example, suffered a dreadful spell, drawing four and losing four, during the campaign. Aside from the 3-1 loss to Arsenal though, Stoke came very close to securing a win or draw in each game. The details count.
United also had a similar sequence of two 1-0 losses and two 2-2 draws during the season. Robin van Persie was injured for the first three games and returned against Newcastle United, although the Dutch striker was clearly unfit. Perhaps the lack of finishing edge helped turn draws into losses and wins into draws?
There is little trend to speak of and the fact that van Persie and Wayne Rooney are among the most consistent finishers in England suggests that the answer lies elsewhere. In fact Data Rant previously noted that a reduction in the quality of chances created was more at fault for United’s performance last season.
This scatter plot, above, charts the relationship between key passes-per-game of each club’s leading creator and final position in the table. There may seem only a tenuous link, although the clear outlier in the upper right corner and bunched data points below the trend line are clearly distinguishable.
However, with outliers removed, the correlation between the number of key passes per game of a team’s leading creator and league position is striking.
Rooney, Kevin Mirallas, Adam Lallana, Marko Arnautovic, Jason Puncheon and Jonathan de Guzman are all relative under-achievers, while Robert Snodgrass performed significantly better than the rest of Norwich City’s players last season.
Rooney’s peer group have been heralded to a varying degrees, but the data suggests that they should have done a far better given their clubs’ standing.
Meanwhile, Juan Mata performed to the expectation of the seventh best side in England. Yet, the gap between Rooney and Mata is staggering. Yet, at the same time, Louis van Gaal’s more fluid style might bring out the best in the Spaniard, enabling the former Chelsea Player of Year to drag United back into the top four next season.
Rooney’s decline has been noticeable and it will likely only accelerate as the England forward ages. The 28-year-old has produced the numbers, especially assists, but the dearth of key passes hints at a measure of luck rather than intention. After all, if a picture is worth a thousand words, Rooney’s output is more at home at Craven Cottage than Old Trafford. In fact the data supports the notion that many hold: it is becoming increasingly hard to justify deploying Rooney in the hole, especially when the chief creator has such an impact on league position.
1) All categories are weighted equally
2) Only players who made more than twenty domestic appearances have been considered, unless otherwise noted
3) Assumptions dictating linear regression have not been held strict
4) All data from squawka