Sunday, 30 March 2014

Swans 3 - Norwich 0 Stats and Chalkboards

I've felt like a result like this has been coming but it's the stage of the season now where results are more important than the performance but it's great to get both like on Saturday.

Arguably the big difference between this game and the previous home games against Palace and West Brom was the second goal before half time, it doesn't take a huge stretch of the imagination to picture a scenario where we'd have beaten either of those teams equally comfortably had we gone in at half time 2 rather than 1 up in those games.
Shots by Minute: Norwich 2 down before having their first shot and only 8 in the whole match, half of which were
Bony now has a Goal or Assist in 10 of 15 games he’s played for Swans in 2014 (and 6 of last 7 games) and De Guzman with most goals in the Monk Era so far with 5 in 731 Minutes (equivalent of just over 8 games).

Apart from Ash's block on the line this was a fairly comfortable victory and means the focus starts to move (a little bit) from the fight at the bottom to achieving as high a position as possible with 11th place still a realistic ambition.

Last season each place in the league was worth an extra £700k, this years TV deal means this has been significantly increased so I'd imagine it'll somewhere around £1m a place so once the first task of Premier League survival is sorted there's £5-£6m extra up for grabs for a range of teams from West Ham downwards.

Other Posts:
Hamstrung: Playing Time and Injuries compared for Pablo/Ozil/Aguero
Leon: 5,000 Passes in the Premier League
Match Predictions: Are you Smarter than Lawro

Twitter: @we_r_pl
Match Stats: Created using Statszone , Whoscored  and Squawka

Wednesday, 26 March 2014

Arsenal 2 - Swans 2 Stats and Analysis

It's difficult to know what to make of that game: Being in front for over an hour, conceding two goals in 60 seconds, an equaliser with Leon in the box and a final few minutes where Arsenal seemed to have given up (or at least given up defending).

With only 40% possession, this was the lowest % of the ball Swansea have had in the league this season by some distance, but this will in part be due to Bony's early goal meaning there a greater incentive to be more defensive although there were plenty of misplaced passes too (although to some extent that's kind of a vicious circle as if you're defending deep and under pressure it's much harder to find an out ball so possession gets given up and the process repeats).
Pass Volumes over Time: Arsenal dominating possession throughout the game but after around 35 minutes really start to rack the passes up
Action area heatmaps per 15 minute periods: Arsenal pretty much camped in Swansea's half but relatively little danger.  Swansea having odd moments of pressure but not sustained activity in final third
Despite dominating the ball, there were only occasional moments of incision from Arsenal prior to the two goals and although there was the odd case of riding our luck with defensive scrambles, Vorm only made two saves all match.
Shots by Minute: Swansea score with first attempt and only have 1 more in first half.  Arsenal created relatively little in the 2nd half other than two incisive moments in 60 seconds (and no further attempts afterwards)
After going ahead against Palace and drawing late on, then going ahead and losing late on against West Brom, to have the lead for over an hour and then seemingly throwing it away so quickly here would have had a massive impact on confidence going in to the Norwich game.  Thankfully Arsenal's meekness combined with Leon's determination meant that instead we left with a point and everyone on a high.

It could have of course been even better, I was amazed after the equaliser how Arsenal's defence seem to disappear, I understand that they needed the three points but they were leaving such big holes at the back that instead of penning us in and making us sweat like they had done for most of the match, they invited the counter attack and there were a couple of opportunities even before the one at the end for De Guzman.

It was good to see the return of Michu to the starting line-up, taking him off after an hour was absolutely the right thing to do as he's still coming back to full fitness and Norwich on Saturday is crucial, but I was impressed that Monk was willing to do this as I'd argue Laudrup overplayed Michu when he came back initially from injury (90 minutes on his return v Hull and then another start 6 days later against Norwich after which he was out for 3 months).  Playing De Guzman on the left hand side was also an interesting call, I'm not sure if it worked or not as the early goal changed the dynamic of the match.

Below are a few other charts of some stats on the game, be interested in any thoughts on which are of interest and which a just too much information.

Passes per Minute by Team: Swansea with the odd period of control but generally found it difficult to string a lot of passes together

% of Total Passes by both teams that were made by Swansea. Little of the ball in first 10 minutes, Swans with just over a third of possession at time of Arsenal's 2 goals with increased possession in final 15 minutes but still under 40% overall
Other Posts:
Hamstrung: Playing Time and Injuries compared for Pablo/Ozil/Aguero
Leon: 5,000 Passes in the Premier League
Match Predictions: Are you Smarter than Lawro

Twitter: @we_r_pl
Match Stats: Created using Statszone , Whoscored  and Squawka

Saturday, 22 March 2014

Everton 3 - Swansea 2 Stats and Chalkboards

I keep telling myself it'll all be OK in the end and that our season won't be defined by games like this one or the one against Arsenal on Tuesday, but we're starting to run out of matches to do something in now.

On the bright side, from all the bookie's odds and predictive models people have put together we're still only around a 10-15% chance of being relegated, luckily games are running out for everyone else as well.

This was yet another game where a promising first half fell away and the match pretty much over after an hour with Everton's 2 goals early in the 2nd half.  I've seen plenty of criticism of Bony's substitution but if Monk felt game was done then there's some sense in it to keep Bony fresh and to give Michu minutes.

Shots by Minute: Swans starting well with a couple of early efforts and a strong last 15 minutes of the first half but the good work undone early in the 2nd
Pass wise it can be seen that after the Everton goal, Swans had the vast majority of the ball and Everton only attempted 3 passes in the last 5 minutes of the first half.
Passing Stats Pretty similar up to Everton's goal with Everton ramping it up again at the start of the 2nd half
A (very) small positive is that we scored the best goal of the game with Bony's finish coming at the end of a move that from Right to Left and back to Right:
Bony goal: Some nice passing and movement and an easy finish for Bony
Looking at the stats from the match, one of the ones that stuck out for me was the attempted take-ons (dribbles) with Swansea only having one successful which came via Chico.

Plenty of activity for the Swans in the right kind of areas but snuffed out by Everton (and in particular by Leighton Baines).
For me the Arsenal game represents a sort of a free hit, if we have another first half like we've had in recent games then there's no reason to think we can't repeat the exploits of the win at the Emirates last season.

Thursday, 20 March 2014

Are you smarter than Lawro?

Back in Dec 2012 I wrote a blog looking at how Mark Lawrenson's predictions were making a profit, this was also reported on by BBC's More or Less showing he was still ahead of the market at the end of the season.

I've had a look to see how he's been getting on this season to see if this wasn't just a one season wonder and if he makes better choices with football predictions than he does his shirts on Match of The Day.

To do this I've taken his predictions as collated on the excellent My Football Facts and matched that with the odds data available at Football-Data (odds as at Friday afternoon, or afternoon before for midweek games).

For the 291 games played in the Premier League so far this season (to 20th March), Lawro has correctly predicted 155 (53%) of the outcomes, but the key will be is this enough to make a profit?

Based on a £10 stake on each of the 291 games, Lawro's selections would have given you a profit of £242.20 if using just Bet365 (the first of the odds makers on the Football-Data list), £246.40 if using Pinnacle (generally the best priced bookmaker) or £287.30 if you had accounts with all 8 of the bookies quoted and picked the best odds for each selection.

Bet365 had an average market of 102.5% (Pinnacle 102%) where using the best odds gives you a market of 100.7% and a 'perfect' market would be where the probabilities of the Home/Draw/Away odds would equal 100%.
Payback if betting via Pinnacle: The first few weeks (usually 10 games per week), show as roughly break-even but over a longer period the good has outweighed the bad so far this season
In the blog back in 2012 I noticed that the majority of Lawro's profit was coming from his draw selections and it's a similar story again this season:
As for last season, greatest part of the profit is where Lawro picks a draw.  36% of these selections were correct where odds provided suggested only 29% should have been draws.
All of the above suggests a 'wisdom of the crowds' and that markets are priced accurately but it might well be (as suggested last season) that Lawro is more willing to sit on the fence than the average punter and that (either deliberately or not) Lawro is exploiting an inefficiency in market where the Draw is over-priced.

Lawro has said his predictions are done by 'gut feel' and the scores he uses tend to back this up,
71 out of  the 73 predicted Draws from Lawro he's predicted as 1-1 and has only predicted 1-0 or 0-1 scorelines 4 times in the season compared to the 58 times it's happened in the 291 games so far this season.  
At first glance it might look odd to put so many draws down as the same score but actually this has been the most likely score for a draw this season so actually makes sense if you're going for a 'quick and dirty' approach, although 1-0 has been more frequent than 2-0 maybe 2-0 sounds more decisive.

Lawro also has particular favourites (or blind sports) which when you look at his predicted table vs. the actual stick out and give the impression he doesn't know what he's doing but ultimately anyone picking on 'gut feel' will have favourites.

The predicted and actual Premier League tables (via My Football Facts).  Man Utd and Cardiff are among the biggest differences but for majority of individual games saying Man Utd would win and Cardiff lose is not that odd a prediction.
The above and last season's results show (however it's put together) that Lawro's selections have been profitable over a reasonably long period, but could more scientific methods give even better returns?

Over at EPL Index, Neil Charles has been using Opta data to simulate matches to predict likely outcomes, ultimately whether it's reading the sports pages, looking at the league/form tables or building a model like Neil has all of these are cases of taking in information and using it to make an informed decision, even if some methods are less emotionally biased than others.

Neil's model has been up and running since November and in that period for a £10 stake per selection with Bet 365 returned a profit of £140.56 (not including last weekend which Neil said was £30 up).  Over the same period Lawro's selections also placed at Bet 365 would have returned a profit of £128.40.
Return over time from Neil's bets
Obviously these figures are not definitive proof that Neil's model is better than Lawro's gut but for me do provide an allegory for analytics within football in general:

  1. Don't discount experience: Lawro might not come across like the sharpest tool in the box, but maybe sometimes he does know what he's talking about
  2. Analytics can be an improvement but it can also be a lot of work for only small gains.  Naturally I'm in the pro-analytics camp but there are rarely easy answers, it needs someone to appreciate the value in those small incremental gains on the bigger picture.  

Other Posts:
Hamstrung: Playing Time and Injuries compared for Pablo/Ozil/Aguero
Leon: 5,000 Passes in the Premier League

Twitter: @we_r_pl 

Friday, 14 March 2014

Hamstrung: Pablo, Ozil and Aguero injuries compared

In a post a few weeks ago I looked the impact of playing time for Swansea on injuries and the domino effect injuries had (players get injured means remaining players have to play more, often getting injured themselves and so on until we ended up running out of midfielders in January).

One of the areas looked at was the playing time of Pablo Hernandez who has (unfairly in my opinion) gained a reputation as being fragile due to repeated injuries this season.  As Pablo got injured again in the last game against Crystal Palace I was planning to update his data but similar injuries in the Champions League to Ozil and Aguero along with talk of 'dinosaurs' and 'incompetence' from Raymond Verheijen made me want to extend this.

Garry Monk said Pablo felt his hamstring pretty much from the start of the match against Crystal Palace, Ozil injured his in the 2nd minute against Bayern, Aguero in the 3rd minute against Barcelona.

The other thing that links all 3 is that they had all played 90 minutes around 72 hours previously to getting injured and have all recently come back from injuries (prior hamstring injuries in Pablo's and Aguero's cases).

Obviously players get injured on a regular basis and hamstring injuries are not rare but for all three to suffer strains right from the start of the match suggests possible issues around overplaying and insufficient recovery time, either from previous injuries or previous matches.

For Pablo, the three times this season the playing minutes have ramped up, he's ended up with an injury, this is far from proof of over playing but does at least flag it up as a concern.
After missing some of pre-season due to injury, Pablo then played equivalent of almost 4 full games in space of 14 days before first injury. After setback on initial return in October, suffered two hamstring injuries after playing equivalent of 3 full games over 14 days
The stop-start nature of his season has meant that Pablo's been given this injury prone tag but there's a reasonable chance that it's playing time rather than 'bad luck' causing them.

Looking at Pablo's minutes for last season, joining from Valencia after the season had already begun, he was pretty much an ever-present apart from a gap of a few weeks in the middle of the season.
Pablo's minutes in 2012/13, the only main injury coming during the game against West Brom. It's not obvious from the 7/14/21 day splits but this game was the first time he had less than 6 days rest between games.  After playing 90 minutes against Liverpool on Sun 25th then starting again against West Brom on Wed 28th
For Ozil, much has been made of loss of form, a perceived lack of effort from some areas of the press who are often using the transfer fee as a stick to beat him with.
Ozil's minutes: from Sep to mid Nov, Ozil played 2 full games in any 7 day period on a fairly consistent basis (includes International matches) with a period around mid Dec where played equivalent of 6 full games in a 21 day period as usually plays full 90 when started.
When comparing this to Ozil's activity last season at Real Madrid, it can be seen that the peaks are at a lower level and less frequent:
Ozil in 2012/13 There are certainly times where Ozil played 2 full games in a 7 day period but overall there isn't the same level of activity of a consistent period that there has been this season
For Aguero, his record this season when he has been playing has been superb (28 goals in all competitions, average a goal every 75 minutes played) so it's easy to see his importance to the team.
Aguero's minutes, before his injury in mid-Dec, Aguero was playing regularly but not at the same volume as Ozil.  The Tue/Wed split of the champions league means sometime a player can have 3 games in a 7 day period e.g., Wed/Sat/Tue which is potentially a key issue to overplaying.  For the two hamstring injuries in Jan/Mar, how much are these caused by minutes played after recovery from a prior injury?
There's always the risk when looking at things after the fact of trying to apply a pattern to something where no pattern exists, there will be other players with similar playing profiles who've not been injured and minutes alone is only a basic measure and doesn't take into account intensity of match, travel etc.,  A player may have 0 game minutes but even being part of a match day squad for a trip to Europe is likely to impact on 2-3 days of their training.

Unfortunately there's not going to be a 'one size fits all' approach to prediction and prevention of injuries and there'll always be the temptation that any given match is big enough for it to be 'worth the risk'.  If you're a manager facing an important match and 'knew' a player had a 30% chance of getting injured early (as an example) it's likely you'd take the gamble anyway, it may not be the optimum decision over a long period but seeing as a club can go from being comfortable to being 'in crisis' within the space of a week, long term planning may not extend beyond the next 4 games if you're lucky.

Minutes played data from Transfermarkt
Injury Data from Physioroom
Other Posts: Leon Britton: 5,000 passes in the Premier League
Twitter: @we_r_pl 

Tuesday, 11 March 2014

Leon Britton - 5,000 passes in the Premier League

I was recently asked by the guys at The Jack Cast podcast to look at Leon Britton's passing given the fact that he's finally broken his duck with his first assist in the Premier League during the match against Crystal Palace on 2nd March.  
On looking at the figures I found that this was with his 4,959th pass in the Premier League so obviously not an assist machine, but that's not what he's there for.  Over the (almost) 3 seasons Swansea have had in the Premier League so far, Leon has been the fulcrum and has to date played 5,009 passes, completing 4,621 (92.3%).  
In Swansea's first season in the Premier League (2011/12), Leon had a pass accuracy rate of 93.4% (2,110 completed from 2,558 attempted) which was higher than any other player in the league that season.
Under Laudrup this season, the introduction of CaƱas along with the occasional injury has meant Leon's influence has been far less, although that may well change under Garry Monk as Leon has played all bar 1 minute of Swansea's 4 league games since the Dane left.  Obviously there were plenty of other rumblings of discontent in the Laudrup era, but his decision to play Jordi Amat who is a centre back, in the defensive midfield position against West Ham was maybe the final nail in his coffin.
In fairness to Laudrup there was some logic in the plan (extra aerial ability to cope with West Ham's main threat), but Amat switched off from a Carroll knock down for Nolan to score the opener.   Football is full of "if-only's" but who knows what would have happened had Leon started, would an experienced midfielder have been instinctively more aware of the threat than a defender playing out of position?
Of those 5,009 passes in the league so far, only 1,574 (31.4%) are what were classed as forward passes (14.5% back and 54.1% left/right), this combined with the fact that most of the passes he makes/receives are short passes gives ammunition to anyone who claims what he does is easy but I'd argue that they'd be completely missing the point.
Passes made (left) and received (right) in match v Crystal Palace. Most passes only a short distance but his availability to receive a pass crucial to keeping possession ticking over.
Leon's pass completion % by match - Overall average is 92.3% but not a single game below 80%.  In the 84 games played in the Premier League to date, Leon's had 6 100% pass completion games (although 4 of those were as a sub).
Season by Season summary for Leon.  After being an almost ever present in the first season under Rodgers, Leon was still pretty much a regular in Laudrup's first season but only played in 39% of all game time in the league for Swansea this season under Laudrup but all bar 1 minute of Monk's 4 league games.
Leon's strength is in his consistency, decision making and ability to read a game.  Sitting in the stands or watching on TV a lot of what Leon does looks straightforward but that's with the benefit of having a wider perspective of what's going on than would be afforded to someone in the thick of it.  He's only 5ft 5 inches and not the fastest but is a great example of how there's still room at the highest levels for someone with a real football brain.
Data from EPL Index
Chalkboard from Statszone

Monday, 3 March 2014

Swans 1 - Palace 1 Stats and Chalkboards

How you feel after this game is probably a pretty good indicator for your outlook on life.  Either this was a disaster and everything's going to shit or given being a man down for the last 10 minutes you're just grateful we got something from the game.

I don't think I can remember a game anytime recently where possession was so one sided but in terms of chances things were equal:
Passing by Minute: Swansea were on course at half time for almost 1,000 passes but the second half was pretty much even in terms of pass volume
Looking at that over time as a % of total passes, Swansea made 84% of all passes in the first half which had dropped to 70% by the end of the match.

  % of all passes by both teams that were made by Swansea - Consistently over 80% in the first half but dropping dramatically as the 2nd half progressed
Chance wise this was very much the proverbial 'game of two halves' with Palace only managing a single shot in the first half and Swansea only 2 efforts in the second.

Total Shots by minute - not a huge amount of action from either side as Palace looked to keep things tight
The risk of overplaying Pablo is something I've looked at before and will return to in the next couple of weeks, that combined with Ash and Bony's illness meant that players were pretty much out on their feet towards the end although that doesn't excuse Vorm's rush of blood.

With two weeks rest (3 for Chico) and hopefully the return of Michu we should over the closing 10 weeks hopefully see a preview of the level of football we'd expect to get next season with no Europa distraction, aside from whenever the Arsenal game is re-arranged it'll be 1 game a week for the remainder of the season with close to a fully fit squad.

Twitter: @we_r_pl
Match Stats: Created using Statszone , Whoscored  and Squawka