Data Viz Done Right

October 13, 2014

Makeover Monday: Arsenal's Injury Crisis - A Story

8 comments
ESPNFC recently published an article providing some details about Arsenal's nearly 900 injuries since the start of the 2002-2003 English Premier League season. Last year, Arsenal crossed the 100 injury mark, suffering 111 injuries in total. This year they are picking up where they left off, with 26 so far this season. In particular, Arsenal continues to be without Theo Walcott and has suffered major, long-term injuries to key players like Aaron Ramsey, Mathieu Debuchy and, most recently, Mesut Ozil.

I found this story fascinating because it finally put numbers to Arsenal's perceived injury crisis.  They do indeed suffer way more injuries than any other EPL team. But what bothered me about the ESPN story was that they basically just listed off a few key facts (quoted from ESPN):
  1. Arsenal players have sustained 889 injuries since August 2002, according to a report by PhysioRoom.com.
  2. The Gunners' 889 injuries over the 12-year period compare to 792 for Manchester United, 620 for Chelsea and 551 for Liverpool.
  3. Abou Diaby, who has recently returned to fitness, has endured 40 separate injuries, according to the study, while Theo Walcott, who is currently recovering from a serious knee problem, features 42 times.
  4. PhysioRoom.com claims 120 of the injuries were of the hamstring variety while six anterior cruciate ligament (ACL) have been suffered.
These all seems like interesting stats, but they're missing something incredibly critical...context.

Without comparing Arsenal to their rivals, how do I know how bad their injury crisis really is? If they're suffering injuries at the same rate as their rivals, then maybe there isn't a crisis after all. But if their rate of injury is higher, then perhaps there is more to the story. Have Arsenal players always been injury-prone or have they increased since they moved to the Emirates Stadium with its rock hard surface?

I set out to understand more by downloading the injury reports from PhysioRoom.com for all teams that have participated in every year of the EPL since 2002-03 (plus a few others that are not included in my final story below). You can download the data in Excel format here.

So in a sense, today's makeover is not a makeover of a chart or dashboard; it's a makeover that takes a text-based story and adds charts and graphs to tell a more meaningful story.

Download the Tableau workbook used to create this story here.

8 comments :

  1. This is so cool !

    ReplyDelete
  2. Hi Andy, I love to start the week with an Arsenal Viz! These data are really interesting and these past seasons, Arsenal was not really lucky with this… But is it really bad luck? As we see, Emirate Stadium could be responsible for this increase (opening in 2006) but , 2008 to 2010 were so bad! (and last season too)

    I don't know about you, but I'd love to get more data about the severity of the injury and the unavaibility of the player.

    The other things to look at could be "transfer period" and injury. For example, the Giroud case: without Giroud injury, no Welbeck. It could be interesting to compare those two players to see if this injury was a "good thing" for Arsenal. (Even if injury is never a good thing but I think you understood my point) I'll have to look for thesse data!

    Thanks for this Viz!

    ReplyDelete
    Replies
    1. Geoffrey, I totally agree that there are a ton more questions left unanswered. The PhysioRoom data doesn't include length of injury. While I could probably cobble that together somehow by going to each of the teams' websites, it would be quite the time consuming effort. Hopefully one day, all of this data will be consolidated and made available to all of us.

      Delete
  3. Great work! Arsene Wenger must read this blog. Or someone should send this to him.
    Just two comments:
    1.The monthly axis could be from August when the season starts to July. Then it kind of lets us see in season and off season a little more clearly.
    2.Weekly scale could be an interesting granularity for the analysis of the premiere league.

    ReplyDelete
    Replies
    1. Alexander, I started the axis in July because that's when the season officially starts.

      Delete
  4. This is really cool, Andy. It might also be helpful to see injury rate per game player or per minute played, to see if Wegner's player rotations are to blame.

    ReplyDelete
    Replies
    1. Totally agree Will! A few comments:

      1. The data you mention is monumentally difficult to get.
      2. The dates injuries reported don't necessarily align with specific games.
      3. I wrote this as a makeover of a text story, but this goes really well with Andy Cotgreave's recent discussion about data conversations. One of the good things this viz has done, is that it has gotten a conversation started and led to more questions.

      Delete
  5. Arsenal needed Ashley Williams of course even before Gabriel got injured in the past premiere league seasons and Everton buy him for a pittance. Just can't work out Wenger every year it's the same.Financially responsible? Arsenal sits on the BIGGEST CASH RESERVES in world football. Yes more cash than those other clubs I need not mention. Arsenal could spend 100m tomorrow and still be considered financially responsible.

    ReplyDelete