If there was one over-arching principle for analyzing soccer statistics, it might be “context is king.”  For example, Arsenal’s Bacary Sagna averaged 54.5 passes per 90 last year and West Ham’s Mark Noble averaged 53.2 passes per 90.  Intuitively, our first reaction is probably that both players exhibit roughly the same level of passing influence—with maybe the slightest of edges given to Sagna. But we are not controlling for the fact that Arsenal led the EPL with 569 passes per game while West Ham was second from bottom, averaging 326 passes per game.  To adjust for this disparity we take each player’s passes per 90 and divide it by their team’s passes per 90, thereby creating a pass usage rate for each player.

 

	Passes / 90	Team Passes / 90	Pass Usage Rate	EPL Rank
Mark Noble	53.2	326.2	16.3%	1
Bacary Sagna	54.5	569.4	9.6%	142

Once adjusted, we now see that Noble was a significantly more influential passer for his team than Sagna and actually recorded the highest pass usage rate of any player in the EPL.  It should be noted that usage rates are not a predictive metric, nor are they meant to be, but they are a very useful tool to help us understand a player’s influence on their team and separate “team effects” from individual statistics.

 

General Usage Rates

Pass usage rate is—to this point—the most widespread usage rate.  Devin Pleuler recently published a nice write-up on the subject, which also introduced the idea of network centrality.  Pass usage rate is a “general” usage rate in that it does a good job of approximating a player’s general influence to their team.  Another general usage rate is the touch usage rate.  It differs from pass usage rate in that it measures more actions than just passes attempted (i.e. if a player receives a pass and shoots or turns it over before attempting another pass), so it is potentially a better proxy for general player activity.  Broadly speaking, touch usage gives goalkeepers and strikers more credit than pass usage and produces a smoother curve with less variance as a result (see thumbnail below).  We have also included Arsenal player’s pass and touch usage rates to further exemplify these differences.

 

 

(Arsenal, 2013-2014)
	Touches / 90	Pass / 90	Touch Usage Rate	Pass Usage Rate	Abs. Difference
Mikel Arteta	95.7	80.5	12.2%	14.1%	1.9%
Aaron Ramsey	98.5	77.3	12.5%	13.6%	1.0%
Mesut Özil	86.3	68.6	11.0%	12.1%	1.1%
Santiago Cazorla	89.8	67.1	11.4%	11.8%	0.4%
Tomas Rosicky	76.7	64.1	9.8%	11.3%	1.5%
Jack Wilshere	82.7	63.8	10.5%	11.2%	0.7%
Mathieu Flamini	77.4	63.1	9.9%	11.1%	1.2%
Nacho Monreal	82.0	55.0	10.4%	9.7%	0.8%
Bacary Sagna	82.1	54.5	10.5%	9.6%	0.9%
Per Mertesacker	61.8	48.8	7.9%	8.6%	0.7%
Kieran Gibbs	76.0	47.7	9.7%	8.4%	1.3%
Lukas Podolski	62.4	46.1	7.9%	8.1%	0.1%
Laurent Koscielny	57.9	41.7	7.4%	7.3%	0.1%
Olivier Giroud	50.4	32.5	6.4%	5.7%	0.7%
Wojciech Szczesny	39.7	18.0	5.1%	3.2%	1.9%

 

Attacking Usage Rates

 

You can measure a player’s attacking influence by looking at their shot usage, key pass usage, and general shot contribution usage.  These were the top 10 in the EPL last year.

 

	Shots/90	Shot Usage (%)	KP/90	KP Usage (%)	Shot Contr./90	Shot Contribution Usage
Luis Suárez	5.5	32.1%	2.6	20.4%	8.14	47.5%
Christian Benteke	2.8	25.0%	2.0	22.7%	4.82	42.5%
Marko Arnautovic	2.9	25.5%	1.9	22.2%	4.79	42.5%
Wayne Rooney	3.7	26.8%	2.1	18.6%	5.77	41.7%
Jason Puncheon	2.8	25.3%	1.8	21.3%	4.51	41.3%
Robert Snodgrass	2.5	20.2%	2.3	25.9%	4.83	39.3%
Wilfried Bony	3.9	30.1%	0.9	9.0%	4.84	37.1%
Kevin Mirallas	3.1	21.2%	2.4	18.2%	5.48	37.1%
Philippe Coutinho	3.6	21.2%	2.5	24.3%	6.13	35.8%
Rickie Lambert	3.3	23.4%	1.7	16.3%	5.02	35.7%

 

Defensive Usage Rates

 

Defensive statistics remain a relatively under-researched domain in soccer analytics.  When people do talk defensive statistics, usually only tackles and interceptions are discussed.  I believe this is a mistake, as tackles and interceptions combine to only comprise 24.4% of turnovers.  Any overall defensive usage rate should also include clearances and recoveries.

 

	2013-2014 EPL Turnovers (By Type)
Tackle	11,153	12.6%
Interception	10,435	11.8%
Clearance	23,459	26.6%
Recovery	43,236	49.0%
	88,283	100.0%

Here are the top 10 in overall defensive usage rate in the EPL last year.

 

	Turnovers Forced / 90	Defensive Usage Rate
Nemanja Vidic	20.0	15.9%
Phil Jagielka	17.8	15.9%
Marcos Alonso	16.0	15.4%
James Collins	17.3	15.3%
Nemanja Matic	17.2	15.1%
Martin Skrtel	18.7	15.0%
Martín Demichelis	16.3	14.7%
Laurent Koscielny	17.7	14.7%
Curtis Davies	16.9	14.7%
Youssuf Mulumbu	17.5	14.5%

It would also be informative to look at tackle, interception, clearance and recovery usage rates, respectively, to get a sense as to a defender’s tactical responsibilities.  For example, Nemanja Vidic does most of his work with clearances (11.4 of the 20.0 turnovers he forces) and is responsible for nearly 31% of all of Manchester United’s clearances when he is on the field.