Tuesday, May 10, 2016

Do Manager Changes Affect Team Passing Style?

Overview
It has become de rigueur for manager’s to proclaim at their introductory press conference their intention to play a pro-active style of soccer emphasizing possession and attacking play.  This analysis attempts to answer one question definitively—do new managers have an empirical effect on team passing style?—while posing a follow up question for further research—can we use this type of data to “type” managers and give better insight for owners and presidents as they undertake manager searches?

Passes Per Possession
There are many ways to evaluate a team’s passing style, but we have chosen to use passes per possession for a couple reasons: it is simple to calculate (team total passes / team total losses of possession) and it is fairly persistent year over year for our sample (see below) so it will theoretically be easier to find manager change effects.  














A higher number of passes per possession indicates a team is more deliberate and possession-oriented in their approach and a lower number indicates a more direct approach when in possession.  To give some context, here are the highest and lowest rated three teams for one year from our sample (EPL, La Liga, Bundesliga).











You might notice that the top teams are generally considered among the better teams in Europe while the bottom 3 are not exactly challenging for a Champions League title.  While we would caution to call a high # of passes per possession a “good” statistic, it does have some correlation with success—as measured by goal differential.


















Manager Change and Passes Per Possession
The sample we are using for this analysis are the 2011-2014 seasons in the EPL, La Liga, and Bundesliga.  Since we are using only full season data we excluded any clubs that experienced mid-season manager changes. We only kept teams that either had the manager for a full two years or teams that changed managers in the off-season.  In total, our sample included 57 seasons where there was no manager change and 26 where there was an off-season manager change.  On average, teams that had a manager change showed a 0.40 absolute change in # of passes per possession and those with no manager change had a 0.26 absolute change in # of passes per possession. We ran a t-test and demonstrated that this difference is significant at a 97% level.  We therefore conclude that new managers do have a significant empirical effect on a team’s passing style (as measured by passes per possession).










Future Work/Questions
Although we just tested manager change effects on one specific metric, the fact that it yielded a significant result is an indicator that other metrics may also be tested (team attacking style, other passing style metrics, defensive metrics).  Over enough seasons and with a large enough sample size we may even be able to start “typing” managers by their playing style in a deeper quantitative way whereas right now most manager evaluations are of a qualitative nature.  For example, Pep Guardiola is generally seen as a coach whose teams favor possession and embody the “tiki-taka” passing style.  This intuition is borne out in the data we looked at as both his move from Barcelona and to Bayern Munich saw a corresponding decrease/increase in passes per possession.



Monday, March 28, 2016

Three MLS Takeaways: Pirlo back?, 2016 LA Galaxy are an actual team,Diego Valeri = pretty good


 1. Pirlo Figuring Out MLS?

After a pretty forgettable 2015 debut with NYCFC featuring listless performances and a dour demeanor, expectations were not particularly high for the Italian international and his teammates in 2016.  However, NYCFC have gotten off to a pretty solid—though not great—start and an improved Andrea Pirlo is certainly helping.  In particular, he and his teammates are communicating better and we can see this borne out in much improved passing #’s year over year.  Although is usage rate is approximately the same at about 14% (very high by the way), his trademark long-passing ability seems to finally be showing itself.  It will be interesting to see if he can keep it up and if NYCFC can establish themselves as a true contender in the east.












 2. The Galaxy experiment just might work

Look at this lineup from the most recent LA Galaxy match, I mean just look at it.  Is this not the most interesting/random team in the history of MLS?  If there is a team that is must-watch right now in the league it might be the 2016 LA Galaxy:
















Multiple former English internationals, maybe the best player in Ireland’s history,  an El Tri star in his prime, the only openly gay player in major professional soccer, a WC final villain, etc. etc.  I am still not sure how all the pieces are going to fit together, but I do know that Bruce Arena is probably the best coach in MLS history and if anyone can it is him.  The early results have been positive for the Galaxy, as seen by their 3-1 evisceration of the San Jose Earthquakes.  A major key has been the surprisingly exemplary early play by Ashley Cole, a player who once famously derided MLS.  If Arena can make these pieces work we may very well be seeing yet another MLS Cup in Carson come December 2016.


3. Diego Valeri is pretty good




Thursday, May 14, 2015

Uptown Funk: What's Ailing NYCFC?

This article originally appeared on mlssoccer.com





Sunday’s Hudson River Derby loss against the New York Red Bulls had to be disheartening for NYCFC.  Despite being up a man for the majority of the match after Matt Miazga received his second yellow in the 35th minute, NYCFC could not take advantage and were easily dispatched 2-1.  As a result, the team from the Bronx has now only one win to their credit over the first 10 games.

Despite Jason Kreis—the successful ex-RSL manager—taking the reigns over a year before playing their first game, immediate success has proven elusive for NYCFC.  It generally always is for expansion MLS teams.  Certainly, it has not helped that of their three highest profile players, Frank Lampard has yet to arrive from Manchester City, David Villa has been hampered by injury, and Mix Diskerud has struggled to lead in the middle of the field.  Kreis’ successful RSL squads all had a clear tactical style and consistent lineups. By contrast, per Opta NYCFC has already trotted out five different formations to start games this season, more than any other team.  All of these issues underscore the simple problem that has led to such a poor start:  the team is struggling to put the ball in the back of the net. NYCFC are averaging a meager 0.7 goals per game, which is the lowest scoring rate in the league—excluding the Montreal Impact.

Looking deeper at attacking data provided by Opta, it is striking how little width NYCFC is showing in attack.  Looking at shots taken by MLS teams in the penalty box, or the “danger zone” as analyst Michael Caley calls it, we can see that virtually nothing is being created by NYCFC from the flanks, as demonstrated by the percent of these shots coming from crosses. 
Shots from Crosses (%)
Team
% Cross
New York City FC
19.4%
FC Dallas
22.6%
Portland Timbers
34.8%
Seattle Sounders FC
35.9%
New England Revolution
36.0%
Vancouver Whitecaps
39.1%
New York Red Bulls
41.2%
Colorado Rapids
43.6%
LA Galaxy
44.7%
Philadelphia Union
45.8%
D.C. United
48.3%
Montreal Impact
50.0%
Sporting Kansas City
50.8%
San Jose Earthquakes
51.2%
Toronto FC
51.5%
Orlando City SC
53.7%
Houston Dynamo
56.3%
Chicago Fire
62.9%
Real Salt Lake
63.0%
Columbus Crew SC
72.0%

NYCFC has the lowest percent in the league.  On its face, this is not necessarily a good or bad thing as it represents a stylistic choice more than anything else.  However, when a stylistic choice is not resulting in goals, then you have a problem.

If the attack is not going to come from the wings, then it has to be generated in the middle of the pitch.  Here again, NYCFC has struggled to connect their midfield to their forwards.  Despite having the second highest possession % in the league, it has been of the toothless variety.  In particular, it appears that Mix Diskerud might be playing too simply.  Diskerud is the highest volume passer for NYCFC, but compared to other high volume passing central midfielders, an abnormally high % of his passes are short ones that do not stretch defenses.  On average, Mix is playing approximately 14 short passes for every longer pass.

Name
Short Pass: Long Pass
Mix Diskerud New York City FC
13.8
Dax McCarty New York Red Bulls
10.5
Tony Tchani Columbus Crew
10.4
Michael Bradley Toronto FC
10.1
Juninho L.A. Galaxy
8.6
Darwin Ceren Orlando City
8.4
Gonzalo Pineda Seattle Sounders FC
7.8
Matías Laba Vancouver Whitecaps
7.6
Diego Chara Portland Timbers
7.4
Lucas Pittinari Colorado Rapids
6.7
Matt Polster Chicago Fire
5.8


Thursday, April 16, 2015

On Crosses and Throughballs

This article originally appeared on MLSSoccer.com

Your team has possession in the final third; what is the most effective strategy?  Pumping in hopeful crosses or waiting to play that killer throughball?  And what can the relationship between these two variables (crosses and throughballs) tell us about each MLS team’s attacking strategy?

Soccer analyst/writer Michael Caley had an interesting article last summer that examined the relationship between shots created by crosses and shots created by throughballs.  Perhaps intuitive, he found that shots created by throughballs are converted at a much higher rate than those created by crosses.  Looking at 2014 MLS data provided by Opta, we can see that shots created by throughballs are converted at a rate almost double of those from crosses.

2014 MLS
Shots
Goals
Conversion Rate
Crosses
1,526
201
13%
Throughballs
362
81
22%


This does not mean that good teams should completely ignore wide play.  The most effective attacking teams usually find a balance between the two.  The best measure of this is a team’s ratio of chances created by crosses to those created by throughballs.  The higher the number, the more reliant a team is on crosses to create chances (relative to throughballs).  This is last year’s MLS data (provided by Opta):

Team
Cross:Throughball Ratio
10.2
7.7
7.5
7.1
5.9
5.4
4.9
4.4
4.1
4.1
4.1
4.0
4.0
3.8
3.3
3.2
3.1
2.8
1.8

Looking at the list, the tendency might be to view a high ratio as a bad thing with many of those team’s struggling to score goals.  However, the woeful Montreal Impact had the lowest ratio, so we cannot draw any definitive conclusions.  Nevertheless, looking at other leagues around the world, the more “attractive” teams tend to have low cross:throughball ratios.  See below for the high/low ratio teams from three major European leagues.  Remember, the higher the number the more reliant that team is on crosses.
 





Other Leagues Cross:Throughball (High/Low)
EPL
Stoke, 39.0
Arsenal, 2.4
Bundesliga
Stuttgart, 20.0
Dortmund, 3.2
La Liga
Levante, 40.5
Barcelona, 2.2

There are a couple possible reasons for this: throughballs may be preferable to crosses when you are facing a bunkering opponent and/or better teams may have the creative playmakers capable of pulling off such cutting passes.  Of course, the opposite may hold for “inferior” teams.  Incidentally, there is much more parity in MLS, so we do not see such wide spreads between the highest and lowest ratio teams.

Looking at current year MLS data, there are some interesting early results.  However, huge caveats here as the sample size on chances created by throughballs (and crosses) is very small and teams have played an inconsistent number of games. Teams are sorted by highest to lowest ratio.

Team
Cross
Throughball
Ratio
32
0
N/A
11
0
N/A
22
1
22.0
16
1
16.0
18
2
9.0
20
3
6.7
26
4
6.5
19
3
6.3
12
2
6.0
24
4
6.0
11
2
5.5
11
2
5.5
13
3
4.3
12
3
4.0
4
1
4.0
12
4
3.0
17
8
2.1
8
4
2.0
9
5
1.8
7
5
1.4


The Vancouver Whitecaps have done an excellent job at creating chances both from wide play and with throughballs, so it is unsurprising to see good early results for them.  In his first year at the helm of NYCFC, Jason Kreis’ team has almost completely eschewed crosses.  On the other end of the spectrum, the Columbus Crew are taking full advantage of new aerial toy Kei Kamara.  As for the CCL finalist Montreal Impact, perhaps the less said the better.