How Well Do Team Statistics Persist Over a Season.

As promised here I've posted below the intra seasonal correlation for some of the more commonly found team statistics seen in soccer.For example shots taken by teams in the first half of the season are strongly related to the average number of shots taken in the second half of the year.However,from the previous post we can see shots are not particularly strongly correlated with success rate.Therefore,although we will be able to predict reasonably well the number of shots a team is likely to have in a future game from past performance,that information will not necessarily be the best to use in predicting future success rate.

From the previous post we can see that goal difference is very strongly correlated with success rate and from the table below we can see there is a reasonably strong intra season auto correlation and for that reason most methods for predicting future performance are based on goal difference.

Yellow and Red cards received by teams are very uncorrelated across a season,possibly indicating that teams can greatly influence this aspect of the game.There is after all a very big incentive to improve discipline to prevent suspensions and the reduction of avoidable cards for transgressions such as dissent should be relatively easy to implement......or maybe it's just that all the dirty players are suspended come Christmas.


Table charting the strength of the correlation between individual team statistics for the EPL's first 19 league games and the second 19 games of the season for the last 7 completed seasons.

VARIABLE.	Correlation from 1st Half of the Season to 2nd Half.
Shots by Team.	0.69
Shots on Target by Team.	0.62
Goal Difference.	0.52
Goals Scored by Team.	0.35
Goals Conceded by Team.	0.35
Shots by Opponents.	0.60
Shots on Target by Opponents.	0.50
Fouls Conceded.	0.37
Fouls by Opponents.	0.42
Corners Won by Team.	0.30
Corners Conceded by Team.	0.44
Yellow Cards received by Team.	0.07
Yellow Cards given to Opponents.	0.22
Red Cards received by Team.	0.004
Red Cards given to Opponents	0.07