Monday 23 November 2015

Has Luck Made the Title Race Highly Competitive?

The 2015/16 Premier League has thrown up a multitude of talking points, ranging from Chelsea and Leicester swapping identities to the log jam of teams that are in competition at the top of the table after 13 matches.

Leicester entered the Premier League as above average Championship winners, so survival in 2014/15 was more likely than not, but with Premier League points sometimes coming in uneven bursts, a title contending run was required to secure safety over the final months of the season.

Despite the encouraging finish to 2014/15, optimism was hardly raised by the appointment of Claudio Ranieri, a manager better known in England for his extreme squad rotation policy than his previous tenure at the head of a title contending side.

Leicester's current position is a pleasing juxtaposition to 2014/15 when they were bottom with 10 points after 13 games compared to topping the table in 2015/16 having dropped just 11 points.

Shooting stats don't mark Leicester down as the most likely leaders of the Premier League, they've been lucky in converting chances in matches where they've not dominated in terms of volume, but they are currently a legitimately improved side from the previous season.

Leicester's 28 points after 13 matches ties with the 2010 Chelsea side as an historical low points total for a table topping team after a baker's dozen since 2000. However, points alone are a poor measure of a team's standing compared to the remainder of the league.

Currently, just four points separate the top five, compared to a nine point gap when Chelsea led the title race with 28 points after 13 games in 2010.

When measured in terms of how many standard deviations a team leading the table is above the current average points total for the league, the 2010 Chelsea team were more dominant than Leicester are despite both sides having identical records.

How Dominant were the Leaders after 13 Games.

Table Topping Team. Year Start. Standard Score.
Manchester U 2000 2.02
Liverpool 2001 2.03
Liverpool 2002 2.07
Arsenal 2003 2.12
Chelsea 2004 2.23
Chelsea 2005 2.22
Manchester U 2006 2.38
Arsenal 2007 2.96
Chelsea 2008 2.30
Chelsea 2009 2.31
Chelsea 2010 2.14
Manchester C 2011 2.12
Manchester U 2012 1.94
Arsenal 2013 1.96
Chelsea 2014 2.51
Leicester. 2015 1.51

(Teams in bold won title).

In 2015 to date, Leicester are just 1.5 standard deviations above league average, the least dominant achievement for a leader after 13 games this century by some distance. 

There are three challengers each within a win of overhauling them, including Manchester United whom they play next and it is tempting to cite the closeness of the title race and Leicester's position at the head of it, as proof that standards may be falling in the Premier League.

However, just as random variation in the matches so far may have been kind to the Foxes, it may also have compressed the higher reaches of the table compared to more recent seasons.

Instead of tracking simply points won by the leaders in shot based simulations of the current table, we can partly estimate how competitive each iteration was by calculating the distribution of standard scores for each table topping team.

Slightly more than 10% of season simulations for 2015/16 give a leader who is less dominant than Leicester are to date. The most likely outcome produces a leader that is between 1.8 and 1.9 standard deviations above average and 22% of simulated leaders have standard scores of 2.0 or above.

Random variation may possibly have propelled Leicester to the head of the Premier League. It may also be responsible for making the current table appear more competitive than it may actually be.

A single anomalous batch of 130 matches is far too early to call time on the title regulars, induct new members or declare a new found equality in the higher reaches of the table, 

No comments:

Post a Comment