Back to sports again this week. With the Premier League season just finishing, we're looking at how well The Guardian predicted the EPL table at the start of the season.

What works well?

What could be improved?

My Goals

I've had this viz on my mind for a couple months now, basically since Arsenal crapped themselves mid-season. I wanted to understand the ebbs and flows of the season a bit better. This also gave me a good excuse to practice using Tableau's story points feature.

So I sat down last night and cranked out this viz and story about Arsenal's 2016/17 campaign, including the up, the downs and the inevitable contract extension for Arsene Wenger.

Enjoy!

I really liked the learnings that I got last Friday from Rhiannon Fox and the cricket viz I ended up creating. It got me to thinking about other data that I could use with a similar visual display to continue practicing what I learned. Arsenal was preparing to play London rival West Ham on Saturday while I was watching my son skateboarding, so I thought I’d create something comparing Arsenal with their biggest rival, Tottenham Hotspur.

I was able to quickly get all of the results from Wikipedia, which I then imported into Google Sheets and then connected to Tableau. I showed a couple of iterations to Gwilym this morning at the Data School to get his feedback and we agreed that displaying goal difference was the most effective display. In addition, I added dots to indicate the winner. The goal difference display helped show the ebbs and flows of the rivalry way better than showing the goals scored by each team in each match as a diverging bar chart.

Click on the image for the interactive version. Does this display work for you? What might you do differently? Leave a comment and let me know or, better yet, download the workbook, iterate on my design and leave a comment with a link to your version. Enjoy!

With two matches to go in the EPL season, Arsenal is in a battle for a Champions League spot with Chelsea and Tottenham and Theo Walcott is leading scorer.  He started out the season in great form, then suddenly tapered off immediately after he signed a new deal with the club.

In Arsenal’s last two matches, Theo has scored two great goals very early on in the game, at the 2’ mark against the champions Manchester United and 20 seconds into the most recent game against relegated QPR.  Theo is back in form.

I was interested to see how Theo has impacted Arsenal’s overall performance.  Use the viz below to see how Arsenal performs when Theo does or does not play (Arsenal have a higher winning % when he doesn’t play, though in a small sample size) and when he does or does not score (their winning % increases by 20% when he plays and scores vs. when he plays and doesn’t score).

In other words, Arsenal need Theo to play and score.

Download the data here and the Tableau workbook here.

Are Premier League referees getting worse? It sure seems that way when I watch games.  And despite the opinion of Sir Alex Ferguson, the decisions do not even out.

What makes it even tougher is when the players dive all over the place with no intent other than to con the referee.  Is anyone with me on starting a campaign for retroactive suspensions for diving?  That would stop all of the diving immediately!  Guaranteed!

Ashley Young has been near criminal in two recent matches.  He’s even been mentioned for a position on Great Britain's Olympic diving team.  Refer to the video of Man U vs. Villa and Man U vs. QPR for some of the finest acting in years.  He really ought to be ashamed of himself.

But it’s not only the PKs that are called; it’s those that are not called as well.  Refer to the highlights, if you can find them, of the Man U vs. Fulham game on 26 March 2012.  The game was at Old Trafford, it was late in the game, there was a CLEAR penalty against Man U and, of course, it wasn’t called.

I’m not saying there’s a bias towards the “bigger clubs”, but looking at penalty kick data sure leans me in that direction.  All you need to do is filter the viz below to only include teams that finished 1-4 and you’ll see what I mean.

The top four teams get way more PKs called in their favor than the rest of the clubs AND they significantly more PKs called at home.  I simply can’t believe that referees are NOT intimidated by Fergie and Old Trafford?

Click on the Manchester United logo to focus on them.  Look at those startling trends that appear at the bottom.  Intimidation at its finest!

If you want to see the details behind the charts, go to the Team PK Stats tab. 

• Look at how many PKs the top four teams have gotten over the year, both overall and at home
• Now compare that to the relegated teams (18-20)

Maybe it’s because the top teams have the ball more and create more situations where a PK could be called. But still, should the numbers be so overwhelming?

As we approach kickoff of the Arsenal vs. Wigan game this afternoon, I thought I’d take a quick look back at the Gunners’ season and when the data says the season may have turned around.

It’s well documented that Arsenal got off to one of the club’s worst starts ever, but gradually they have come back and are currently in third place.  With five games remaining, their magic number over Spurs and Newcastle stands at 11 and 8 over Chelsea.

“Magic number” is a phrase we use in the States, particularly with baseball, “to indicate how close a front-running team is to clinching a season title (or third place and a Champions League automatic qualifying spot in Arsenal’s case). It represents the total of additional wins by the front-running team or additional losses (or any combination thereof) by the rival team after which it is mathematically impossible for the rival team to capture the title in the remaining games.”

Many people point to the goal below by Bacary Sagna when Arsenal were down 0-2 against Spurs on 26-Feb as the turning point in the season.  (Pardon the poor quality; it’s all I could find on YouTube.)  I must say that I love the way Sagna took the goal, followed the ball into the goal, picked it up, ran it to half field and all but said “I’m sick of this!”  The entire attitude of the team seemed to shift on this one goal.  I get the chills every time I watch it.

Again, I have no doubt about the attitude shift at this single moment, particularly after back-to-back poor results against AC Milan (Champions League) and Sunderland (FA Cup).  But looking at the data for the EPL only, one particular match stands out as the turnaround point..the 7-1 thrashing of Blackburn, whom Arsenal somehow managed to lose to during their early season swoon.

Below you will see four chart, all which highlight this 7-1 game.

1. Points Trend – the upward trend of full-point matches clearly starts with the Blackburn match
2. Points vs. Possible – Here, you want to see a flat green line, which indicates full points are taken from the match.  Look at that long run of results that starts with the Blackburn match.
3. Table position – What an ugly start to the season!  There was a recovery for a few weeks 1/3 of the way into the season, but another string of poor results began with the 0-1 loss to Manchester City.  But the run of results beginning with the Blackburn match, combined with a significant dip in form by Spurs, has pole vaulted the Gunners into 3rd place.
4. Score vs. Result – This is a simple scatterplot. The darker the bubble, the more results for that score.  Excluding the 2-8 drubbing at the hands of Manchester Units, Arsenal have lost every match, bar a 0-2 defeat by only one goals.  This indicates that they have been in every match, but haven’t been able to score late to turn the result around.  But look at our wins, the scores have been tremendous with a but more than a 4-1 average score.

Touch wood that Arsenal will hold on to third place, and please, please, please RVP, sign a new contract!

If you love soccer, then it’s likely that you follow the EPL.  My favorite team?  ARSENAL!  Did you see the incredible goal by RVP Saturday against Everton? You may never see better technique and now he’s only one goal behind Thierry Henry’s team record for goals in a calendar year.  Please Lord, keep RVP healthy for a full season!

And if you love soccer and you love stats, then check out Soccer by the Numbers. Chris Anderson writes many quality posts and recently he blogged about points and relegation.  I wanted to take Chris’ ideas a step farther.  I needed a richer dataset than what Chris was able to provide, so I downloaded the final tables (i.e., standings) from the EPL back to the 2001-02 season from ESPNSoccernet. You can download the full dataset here.

I borrowed (or is it stole?) Steve Wexler’s technique for providing instructions (hover over the EPL logo to see what I mean).  There’s lots of interactivity in the viz, so first check out the instructions, then start clicking around. 

Answer this: How many teams have qualified for the Champions League with a negative goal differential?  Who were they? What else can you tell me about the team(s)?  Post your answer in the comments.