Month: February 2015

Over the Christmas period the boards of Crystal Palace and West Brom decided, probably wisely, that they needed a change at the top. Alan Pardew flew home from his North East exile and Tony Pulis got the call he'd been waiting for since August. On January 1st, Palace stood 18th and West Brom 17th. Both teams were seemingly facing the very real prospect of fighting against relegation. A little under two months on, they now sit 13th and 14th, each 5 points clear of safety and whilst it is still early days for both men, and the samples are therefore small, analysis seems to show both men are doing well in their new roles. Let's have a quick look at some of their numbers: 1. Pardew Pardew has benefited from 4 of his first 6 games being at home, but has so far managed to turn Palace into a positive shots team. There's nothing much going on in the raw conversion rates but the Finishing +/- (PDO) numbers are revealing. Under Pardew, they are enjoying a favourable run and whilst it may or may not continue (Pardew's priors make me sceptical), one thing is for sure: the ten points gained quickly here have given Palace an extremely strong platform to repel the threat of relegation. I stuck up for Warnock a bit when he went, but with Pardew making an instant and strong impact, his tenure has been quickly forgotten. 2. Pulis I imagine Tony Pulis to have a whimsical poster on his office noticeboard that says something like 'An away point is always a good point'. How else to explain creating only five shots against this Sunderland team? Pulis teams always have sub-par shots ratios, and that's quickly taken hold again. Intuitively, this is a bad thing, but as Pulis has shown repeatedly, his schemes are effective and every point earned from a drab draw seems part of the wider plan. Pulis teams always score goals at below league average rate, under 10%, and that's happening too. Pulis teams always concede goals at less than league average rate? Yep, we're there. And Pulis teams always run a positive Finishing +/- (PDO) number.  All present and correct. In only 6 games, Tony Pulis has successfully attached his stringent blueprint to West Brom and gained 9 points. Like Pardew's efforts, this has given his team an excellent platform to repel relegation. Southampton: no middle ground It has been widely discussed that Southampton season has exceeded even their wildest expectations. Koeman's recruitment now looks a shrewd continuation appointment and the predicted mid-season slump hasn't quite appeared. In fact, they are still doing the the things well that they were earlier in the year. Their defense is formidable and still tricky to breach, nobody beats them easily and they are still firmly in the mix for the top 4. Though this weekend's defeat to Liverpool was certainly a blow, it was not as chastening as the result may seem. Since drawing with Villa in late November, Southampton have played a further 14 games. Their record over that period is 6-3-6 but arguably, of those 9 drawn and lost games, 6 of them they can consider themselves somewhat unfortunate not to have generated more points. Their inability to convert their chances has cost them in each game: I've got some unpublished research that suggests that the value of those shots that Southampton left on the table combined from a game to game basis is a minimum of 4 goals and simple average conversion rates for both shots on target and all shots suggest 6, so when you consider how many points these invisible non-goals could represent, it's a grim tale. And it's not as it their misfortune has been leveled out elsewhere. Only once have they won a game that they've been significantly dominated on shots, the 2-1 win at Newcastle. They also have a weird trend of blowing either hot or cold with their opposition in raw shot conversion rates: As we can see, they've fallen in another hole, just as the opposition has climbed out. Their achievements this season make criticisms seem harsh, but it genuinely appears that securing further back up for Pelle would have been a shrewd January decision.  His form, which has decisively cooled since his early hot streak, is currently vital to them but largely absent.  If they continue to get positive results between now and the end of the season, yet come up just short, they may have every right to feel frustrated, despite their best league finish in more than a generation. Obligatory Tottenham bit With a cup final on the horizon and a fierce London derby to contest against West Ham, it was exciting to see the players putting in extra effort and a dashing performance to further stake their claims for a place in the big game. Or not. That this match came after a Thursday night Europa League tie will have escaped nobody's notice and nor will the meandering non-performance that came with it. With the Fiorentina tie in the balance, it's a difficult situation to analyse.  Pochettino quietly seems to not care for the European ties, quite rightly understanding that his long term achievement will be measured by league performance.  A cup along the way? Why not?  But let us not allow it to divert too readily from the case in hand: the league. And that is why it was so disappointing to gift West Ham a nearly decisive advantage.  Big Sam can load up a tactics bus, but he can't always drive it to it's destination and as has frequently occurred recently, they gave up a ton of shots.  Tottenham's minor statistical surge continues apace, but when married with chasing a game and the ugly lure of score effects, it appears less admirable. Harry Kane showed his fallibility by proving he's not the dead ball genius he thinks he is but quickly redeemed himself by gobbling up a heap of rebound flavoured fortune. Worryingly, moving into a busy period, Eriksen appears to have slid from an earlier peak and Lamela still looks like the most extravagantly gifted workhorse you'll ever see. Goals from him are long overdue. So, a relaxing break in Florence awaits, punctuated by a football match and it's all systems go for a Cup Final, a match that will seem vastly different depending on the result.  A win will define it as glory and success and fun and adoration, a loss will look like an unnecessary addition to the fixture list.   Thanks for reading! ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Find me at @jair1970 (A quick aside, I wrote a post here in which I suggested some reformatting of PDO, Mike Goodman suggested calling it 'Finishing +/-' and so I kinda feel I should go with it.)

Every year some teams seem to click.  They embark on long undefeated runs and record impressive victories.  The media get excited and players win awards.  They might even win titles.  On some occasions this is an accurate reflection of a team's quality, but on others it's a comparatively brief flirtation with the desirable end of random variation.  So this year, are Chelsea a decisively good team or are they just riding a huge wave? Let's find out.

How good are Chelsea?

It was easy to get irritated by some of the media fawning over Chelsea as they skated happily undefeated through Autumn.  Fabregas fed Costa repeatedly and the desire for a new team of 'Invincibles' led to a lack of wider critical analysis.  Despite Mourinho's CV being full of changes effected at a pace akin to the Fonz's ability with jukeboxes, this time it had taken longer and only the shrewd recruitment of top class players, a neat trick available to very rich clubs, had seemingly raised Chelsea's performance level.  All hail Jose!

I had reservations.  Chelsea were good, but despite making their annual meal of the Champions League and throwing in the odd duff performance, so were Man City.  In fact, so are Man City.  Most recently, their impressive limitation of Chelsea to three shots at Stamford Bridge was a clear indictment that this Chelsea team were maybe not the second coming.  Samir Nasri, ever the shrinking violet, agreed:

“I’m a big fan of Mourinho but I am not impressed with his team, not at all, we have played them twice, one time with 10 men, and we were better than them. Then we played them at the Bridge, and we were better than them. When I have seen some of their games, I don’t think they are that fantastic – they are just strong and have a good striker up front.”

So, where are we?  Nasri's biased slight isn't provably untrue, yet Chelsea sit contendedly and clearly on top of the league.  City follow at a respectable distance.  Why?

Sometimes the glaringly obvious can stand clearly in front of you yet appear invisible.  A finely honed contrariness and a tendency to try and look for nuance can leave you peering around the sides and neglecting the emphatic truth.  Then you refocus and it hits you like a brick.  Such a wave of simple realisation occurred to me earlier this week as I was pondering this season's Premier League title race.  Chelsea are that team.  Every year we get at least one, and this year it's Chelsea.

What the hell am I on about?

Okay: a Premier League season consists of 38 games, which in the scheme of trends and variations is a small sample.  Each season, within that small sample it is possible to identify teams that have over or underachieved when compared to what might be expected from baseline metrics.  Most often, due to proven repeatability, these will be based around shots and their relationships with goals and/or points.  What we're looking at here is the top of the league and each season, of the contending teams, one or more learns to fly.

It's relatively straightforward to build a model or translate existing metrics into points totals that reflect these underlying truths, without delving into the complexities and extensive data collection required for expected goals (James Grayson is the flagbearer in this realm).  I've looked at the total shot ratios, adapted the same to incorporate conversion rates, then shots on target ratios and finally a version of Grayson's Team Rating.  This creates subtly different results and rather than give a single points figure, given we're dealing in estimation, we get a points range.  When comparing actual points to derived expected points totals, the most overachieving sides of the last 5 seasons are as follows:

We have representatives from each season here, 4 of 5 title winners and 3 of 5 runners up.  Chelsea's phenomenal 2009-10 title side ranks a clip behind (however, in raw terms, that team is way ahead of all other teams on the list).  Also close up is the 2012-13 City side that meandered as Mancini edged towards the exit whilst Ferguson's last team flew.  Interestingly, the only top 2 team that has a mediocre ranking is Ancelotti's 2010-11 Chelsea side, but with 71 points, it was a particularly low total for second place.  Man Utd had it easy that year. Otherwise we have:

• Four Ferguson Man Utd teams, with little surprise that his final two head the list
• The Man City team that memorably dueled and beat Utd in 2011-12
• Three teams from last season.  Arsenal overachieved significantly against, for them, moderate underlying numbers and were nominally in the title mix for about two thirds of the year, Liverpool had a phenomenal attacking season but were pipped by Man City, who matched them going forward and held a decisive advantage defensively.

What has this got to do with this season?

This year we have a functional duopoly of Chelsea and Man City, two teams well matched by skill but divided by small degrees of random variation. In a neat reflection of core performance indicators, after twenty games, Chelsea and Man City had accrued identical records.  Since then, their results have diverged and if we again look at projected points, we might be surprised that Man City's totals bear greater resemblance to expectation than Chelsea's.  Projecting forwards, Chelsea 2014-15 are quite likely to end up ranking 3rd, behind only Ferguson's last two squads at the top of the original table.  This is an extremely high positive variance and when considering it is building on a contending base, it is highly likely to generate the title.

We can see the top 8 positive variances for this season here:

From this, and knowing how similar City and Chelsea's underlying numbers are, we can estimate that Chelsea's advantage caused by random variation (or even luck depending on your inclination!) to be somewhere between 3 and 9 points.  That they currently lead by 7 bears this out quite tidily.

A red-hot striker helps

This year Chelsea have Diego Costa finishing chances at a rate of 28%.  This is incredibly high, literally 'Papiss Demba Cisse has hot feet' high.  His last two seasons were 25% and 20% which implies he may be an above average finisher anyway, rather than a Cisse-esque streaky converter.  Liverpool and Man City last year had Suarez, Sturridge, Toure, Dzeko and Aguero all converting chances at extremely high rates. (In fact, Dzeko consistently appears high up in conversion rates, his long absences this term may well have impacted on City's effectiveness.) Ferguson's Man Utd teams had combinations of Berbatov, Rooney and Van Persie all scoring at high rates.

Having a hot striker contributes massively towards the 'for' end of 'conversion dominance': the rate in which a team converts minus the rate in which they concede.  Here are the same teams from the original chart plus City, Utd and Chelsea from this season:

All of the teams in the initial chart converted chances at a far higher rate than their opposition.  This season both Chelsea have a conversion dominance of around 6 percentage points (14% for, 8% against), Man City's is 2 percentage points (12% to 10%). Simply, Man City have not performed like Champions in this metric. Interestingly, part of Man Utd's continuing success despite performances can be explained here. Van Gaal has followed Ferguson here. Only time will tell if he's able, like Ferguson, to sustain it over multiple seasons, a trend which possibly suggests tactical or systematic methods.

Get shots on target

The top 4 teams in my database for turning their shots into shots on target are the top 4 teams from the initial graphic. If Chelsea maintain their levels (38%), they will rank 3rd.  Chelsea's current rate of dominance in this metric in relation to their opposition is 2% higher than anything else i've got recorded.  They get their shots on target and they stop the opposition doing the same at a very high and likely unsustainable rate. Grayson's Team Rating already cleverly incorporates a similar concept into it's calculation and it's clear that it is an important influence.

Again, we find Van Gaal's Utd scoring highly here; at least in the plus side.  They rank 2nd in the league for turning shots into shots on target (37%) but intriguingly give up shots on target at nearly the same rate (36%).  One might expect this to indicate potential problems but when those same shots on target are converted at 37% For and 25% Against, it looks like a big thank-you to David De Gea.

Any hope for Man City?

Man City are again this year, top class.  Their issues, which start with the seven point deficit, could well be unsolvable given the tiny sample of 13 games remaining.   They simply haven't turned their clear quality into enough points.  In nearly every game that they've dropped points, they've been the better team and have generated more shots and chances than the opposition.  The random variation up until this point has given Chelsea what could well be a decisive lead and the only slight hope I can muster revolves around the Champions League.  Mourinho seemed to prioritise the Champions League last year despite being in league contention; they lost to Villa, Palace and Sunderland in weekends prior to three of their six knockout fixtures and of course, famously won despite fielding a weakened team at Liverpool prior to another.

Whilst Man City also remain in the Champions League, their route is heavily blocked by Barcelona.  Chelsea's competition nous gives them an edge over Paris Saint Germain and if they progress, their fixtures become interesting. A quarter final tie will give them a midweek/weekend run of:

Champions League Quarter Final Leg 1

(H) Man Utd

Champions League Quarter Final Leg 2

(A) Arsenal

whilst a semi final would create this:

Champions League Semi Final Leg 1

(H) Liverpool Champions League Semi Final Leg 2

It is ironic that Man City's hope of rechallenging for the title may rest on their own departure from the Champions League and the continued progression of Chelsea in the same competition.

Conclusion

The statistically best team of the enlightened stat era (2009-14) was, by some margin, Ancelotti's 2009-10 Chelsea team. They scored the most goals, took a higher percentage of shots and shots on target, prevented the opposition doing anything much at all and only the sustained brilliance of Man Utd under Alex Ferguson stopped them winning the league with ease. This Chelsea team is a clear step below and maps very similarly to this year's Man City side. Both are clearly a step above the opposition in the league this year but compare only adequately to former title winners. In a season in which shot totals and goals have reduced year on year, defenses have defined the main storylines in the league, Southampton and Man Utd particularly.  One can speculate as to factors involved; World Cup hangover, increased focus on the financial incentives or even Financial Fair Play but with the pragmatist's pragmatist in charge of the leaders, it is no surprise that efficiency has come to the fore.

Thanks for reading!

Chelsea are great but... With a Yaya-free Man City stuttering badly and Chelsea eking out a win against the mighty Villa, there appears to be very little juice left in the title fight.  I was prepared to row against the models and say 'not so fast' last week when the gap was 5 points, but we can't be far away from yet another bookmaker payout stunt and that usually means curtains.  That neither team played well against moderate opposition suggests that further twists could occur when the Champions League rears it's head again, but as its stands you'd need to be either brave or stupid or a fan to be actively preferring Man City.  A couple of small asides: regarding 'Chelsea are great but it's all going their way' their conversion dominance (the rate in which they convert all shots compared to their opposition) is superseded only by Alex Ferguson's last two seasons in recent history. That's as clear a sign that you're all aboard the happy train to Luckysville as you'll ever get, those Ferguson seasons were crazy. Elsewhere, if considering 'Chelsea might be great but possibly unsustainable', their shots on target ratio (0.682) exceeds their total shots ratio (0.605) by a rate that exceeds the next highest in my data by a huge margin (0.077 to 0.057).  In a sample of 120, that's an enormous difference and will surely reduce over the last 14 games.  Logically their shots are going to get worse at some point and maybe then the kind of performance that generates a slight victory over Villa becomes a draw.  But time is short and the lead has grown.   Quirky mini-stats, sure, but intriguing nonetheless. So, to other parts of the league, where high interest is retained. This chart shows +/- shots and shots on target throughout the league and is ordered by the shots on target side: There are distinct bands of teams here.  The top two are joined by Southampton, Arsenal and Liverpool in consuming the majority of positive shot totals in the league.  Indeed only 8 teams are in credit for both metrics.  Everton have a weird blend of being a minus shots team but 6th best for shots on target and QPR and West Brom have an unenviable record of scoring worse for shots on target that pure shots.  Bizarre stuff and something to work on for Tony Pulis and Maybe Tim Sherwood. Sunderland: entertain your fans! Earlier in the season I figured I had defined the 'bad' teams in the league.  There were seven of them and it seemed straightforward: they barely ever won and were doomed to sink towards the bottom as time went on.  Well, there are still seven bad teams in the league and they fill the bottom seven positions. The only caveat is that one team has escaped (Palace) and been replaced by another (WBA).  The Pardew honeymoon has given Palace a nice two win cushion away from the relegation zone and 'Pulisball' has so far failed to bed in at West Brom.  Ah well, we can't always be right. There really is a grim reality for the bottom seven: none has won more than 5 games, they've only won 6 games between them in the last six rounds of matches and only one was against a team other than themselves (Hull 2-0 Everton).  None has won a single match in the last three rounds of matches either. QPR have big issues having failed to beat a team outside this group all year (thank you and farewell, Harry) but the reason i'm writing this and you're reading it is Sunderland. As I trawl the numbers, occasionally something leaps off the page and in this case it wasn't pretty: Sunderland's last 5 game shot ratio is 21%.  I will admit i'd noticed their miserable shooting totals a couple of weeks ago, but they escaped reporting as they'd played tough games.  Now after creating so little against Burnley and Swansea (despite gaining 4 points!) they get the mention.  It's not only very bad, it's historically very bad: As we can see, being this bad isn't necessarily terminal, it's pretty much a coin-flip whether a period in which a team creates barely a thing will relegate them but pity Sunderland fans! They've hit a sub-30% TSR period in every one of the last four seasons! That's a tough sell for season tickets. I don't watch enough Sunderland games to pin down this lack of creativity but I do have insight into their newest signing, Jermain Defoe.  On the plus side, every club facing a relegation battle needs a regular goalscorer and throughout his career and with two goals already, Defoe has been just that.  In contrast, despite many great goals and a long career, Tottenham fans were not sad to sell him to MLS.  Why? Jermain Defoe has marvellous highlights packages.  His further contribution is negligible.  Over his career he averages 17 passes per game.  In a handful of minutes with Sunderland he's down to 13.5.  These figures include any number of kick offs!  Very little is going on elsewhere (he creates very little for others) and this could have repercussions for Sunderland's future shooting ratios.  Defoe is happy to shoot but his lack of team contribution can make it seem like his team has ten men.  So a Sunderland team already struggling to create chances has simultaneously reduced the wider efficiency of it's forward line whilst probably ensuring more goals. It's quite the quandary! Luckily for Sunderland, even though much of their play has been bad, that's not been a trait unique to themselves.  Three from seven will go and for now, none of them have been impressing. Obligatory Tottenham bit I've theorised before that Wenger has switched some of his tactics in big games this season.  It has seemed that after the series of chastening defeats his team met last season, he's decided to be more pragmatic, particularly away from home.  The excellent result at the Etihad, though functionally a little flattering, was a strong endorsement for percentage tactics but that and the home win against Southampton have been the only wins against 'good' opposition this year.  Despite season long underlying shot numbers indicating Arsenal being a strong side, warning signs were loud in the 2-2 draw at Liverpool in which they created little and allowed Liverpool an avalanche of 27 shots. And so the North London Derby came to pass and it seemed a finely poised affair.  However, a close game wasn't what panned out: this time alongside another concession of an avalanche of 23 shots was a second natural disaster: a HurriKane. Tottenham's season continues to resemble Andre Villas Boas first year: the 'Bale year', at least on the surface.  Both Pochettino and Villas-Boas started the year 5-2-5 and suffered some very poor defeats. Then, powered by a strong emphasis on fitness and the gradual influence of their methods, both have overseen a good run and dramatic wins powered by star players scoring late goals. At this point Villas Boas' team had 42 points (12-6-6) and went on to only lose two more games in finishing a point behind Arsenal in 5th. Pochettino now has 43 points (12-4-7) and the confidence of his young team. Under the hood couldn't be much more different and it's represented in the play. Villas Boas emphasised control and shooting which gave him great underlying numbers albeit in a strange year.  Pochettino has struggled to maintain anything above par shot ratios but has emphasised energy and pressure, which came together to great effect against Arsenal. In the absence of the Europa League, the trajectory is generally up, but still the repeated success in close games tempers expectation. If we refer back to the shot chart from earlier, 5 teams look to be superior in this league, and Tottenham aren't yet one of them. Still, with one win separating 3rd and 6th and Liverpool looking generally sharp and only a further win away, there is plenty of juice in the Champions League race. Thanks for reading!