Thursday, 1 June 2017

Lawro: Master Bayesian

With another season over I wanted to look again at the accuracy of Mark Lawrenson's predictions in the Premier League.  I've been doing this for a number of years now, starting with an analysis of the 2012/13 season and I'm always amazed at how well he does.

At face value, Lawro's table based on his weekly predictions for the BBC look a bit ridiculous, not least his prediction that Liverpool would go through the season unbeaten:
League Table of Lawro's predictions (via BBC Sport)
If you'd used his selections and placed £10 on his predicted result (Home/Draw/Away), you'd have made £501.50 profit from 368 matches (I've excluded the 12 rearranged games) and actually made a small £7.45 profit on his Liverpool predictions.

Lawro's 92 points prediction for Liverpool may seem a bit extreme but you have to consider that this is built up from a series of individual predictions rather than a single prediction of their points total.  In any single game it may make sense to not predict Liverpool will lose (even if you put aside the fact he's an ex Liverpool player).

I previous years most of Lawro's profit has been derived from sitting on the fence more than the average punter and taking advantage of the fact that draws are often overpriced as people in general want to back a winner rather than a stalemate.

This year however, his profit (and I'm sure what has been a bit of a hit on the Bookies in general) comes from the fact that the bigger teams have got their act together and this season has very much been a two-tier league (or 3 if you consider Everton in no-man's land on their own).

If I had to summarise what I thought made Lawro successful all these years, I think it's the fact that he isn't too swayed by short term noise and to some extent you could largely predict his predictions from early on in the season (not least the scorelines used)

For years now, Lawro's kept a pretty simple system and almost always predicts a draw as being 1-1 rather than 0-0 or 2-2, as mentioned in previous years this makes sense as it makes you more likely to be closer to the true result as although betting wise predicting 1-1 when a match finishes 2-1 is no closer to being right than predicting 0-0 it 'feels' closer
The difficultly of any prediction system or model is how much to weight the recent past vs. more historical data. e.g., Is form over the last 1/3/12 games more predictive than what happened last season or even further back.

A great example of this would be Leicester, although a serious title defence was always going to be incredibly unlikely, their results under Ranieri could also be considered to be somewhat surprising.

Obviously clubs don't work in a vacuum and changing managers impacts things (both positively and negatively I can tell you as a Swans fan), but trying to judge whether something is an outlier or the new normal is hard.

People often talk about things 'regressing to the mean' but the whole issue with that is it assumes you've predicted the right mean to start with but as Lawro's predictions have proved over the years, having an opinion and sticking with it isn't the worst strategy in the world.

I'd like to thank MyFootballFacts for collating the Lawro results each week and for collating results and betting odds, both are great resources.

It's still a work in progress but I've used the info from the Football-Data site to create an interactive dashboard of shots taken/faced by each team:

Twitter: @we_r_pl

Saturday, 13 May 2017

Llorente: Lion King

With just 2 games left, it's going to require a huge team effort to get over the line and although I'd love to think we'll be safe by Sunday afternoon, I think it'll go down to the final game. One of the key things that's even kept us in with a chance is the goal scoring of Fernando Llorente.

Over the course of his career, Llorente has focused on doing his work 6-10 yards out from goal which is a large reason why any criticism of his sprint stats is misguided. As with any stat, context is king and Llorente's relative lack of sprinting isn't the sign of a lazy player, more one who is doing what he's good at and what he's been told to do. If you used him for an aggressive press you'd end up with the worst of both worlds, it wouldn't be very effective and you'd also then knacker him out making him less effective.

Llorente's shot location in the League games over the last 5 seasons, focused on the danger zone
For the Swans, the location map is pretty similar, he has 13 goals from his 50 shots with anything long range at a minimum:
Majority of Llorente's activity is within 10 yards of goal
Not surprisingly, an awful lot of that shot activity are headers with 35 of Llorente's 50 shots (and 7 of his 13 goals) coming via his head.
Opta have reclassified his goal v Everton as 'Other Body Part' but I'm keeping it as a header
Llorente using his head a lot is no big surprise but the fact that 70% of his attempts were headers actually puts him quite a way out in front of 'similar' players (Rondon 42%, Benteke 47% and Crouch 50%), also no surprise that he has more headed shots than today's opponent Jermain Defoe but was interesting that 0 of Defoe's 96 attempts have been headers.

One thing that should be highlighted though is the comparison with Llorente's fellow Spaniard Baston. Looking at things now, Llorente seems a massive success (and supposedly coveted by Chelsea during the Jan transfer window) and Baston a flop.

Comparing their figures though, Baston has scored 1 goal in his 549 Premier League minutes. The fact that those minutes are spread across 18 games (athough only 4 starts) makes it feel as if he's had plenty of chances and not taken them.

As a comparison, in the first 549 league minutes Llorente played, he also scored only 1 goal. You could argue it's taken time for Llorente to settle in and for the team to work out how to make the most of him but surely you could put the same case forward for Baston.

Whether he'll come good at some point is difficult to tell but certainly too soon to write him off, even if this season (at least so far) has been a bit of a waste for him.

Opta Data via Statszone, Whoscored  Squawka

Sunday, 30 October 2016

Swans 200: Swans Managers compared

Monday night sees the arrival of Swansea's 200th game in the Premier League. I'm fully aware that Swansea City existed before the Premier League but it's still quite an achievement for the club to now be in its 6th consecutive season in the Premier League even if the money and notoriety that brings seems to have poisoned an awful lot of the club.

Away from off-field matters, I've started to look at a number of stats around our time in the Premier League so far, the first one being performance by manager:

When looking at a rolling 38 game period (i.e., the equivalent of a league season), there have been some ups and downs. Laudrup's league activity started well but started to dip shortly before the League Cup final and at the time of his sacking Swansea had taken 36 points from their previous 38 games which is arguably the kind of tally that would get you relegated if in a single season.

The high point came towards the end of Monk's full season in charge (2014-15) when the figure was 59 points from a 38 game period.

At the time of Monk's sacking Swansea had 48 points from the previous 38 games which is pretty much the average for Swansea's time in the PL as a whole.

Guidolin was in charge for 24 games (although was ill for part of that time and question how much influence he would have had for what was technically his 1st game vs. Watford), but during his tenure, Swansea's 38 game average never went higher than 49 or lower than 42.

When split by manager, the thing that stands out is that Rodgers had 47 points from his season in the Premier League with the Swans and that's pretty the same rate for the 161 games (46.3 points per 38 games). For the last 5 seasons at least, Swansea have been an upper mid-table team with a variance of a few points either way.

Whether an underwhelming couple of transfer windows have changed all that we'll find out in the next few months or possibly sooner if things don't start to improve.

For anyone interested, an interactive version of the 38 game rolling average by manager is below (and also available here if any problems or you want to view full screen).

Monday, 10 October 2016

Giggs, Savage and Content: The New Numbers Game

Media and Journalism are a far different thing today to the past, as referenced in Simon Kuper's excellent piece on the change:
Part of Kuper's piece which is well worth a read
What's this got to do with Swansea City? If you haven't already seen it, Robbie Savage's piece on why Swansea should have 'Given it to Giggsy'  is probably a masterpiece of the new world of 'content'.

Balanced and nuanced debate generally get you nowhere, it's more important that you are heard (and read) than what you actually have to say.

Savage's piece came out on Friday around 8pm, with the Mirror itself tweeting about it, then the man himself (along with a subsequent tweet on Saturday morning).  As they used a Bitly link it's possible to see the kind of level of activity it got:
These figures are for clicks for this link only so won't include activity which directly refers to the Mirror's URL (of which there'll be plenty), but these alone are fairly impressive when you think usually any response from a tweet dies out within 15 minutes (if not sooner) unless it goes viral.  If you put the article link  into the search for twitter you'll see a couple of Mirror journalists promoting it, alongside plenty of people linking to it in tweets saying that Savage has lost the plot.

The following day, Football 365 did a fantastic bit by bit takedown of Savage's argument:
The main thing to note here is the retweet volume, over a thousand retweets where they'd normally get double digits so what we are left with is:
  • Man with reputation for saying daft things, says something daft, gets a reaction
  • Someone points out daft things have been said, everyone laughs at daft man
  • Someone points out that some people have pointed out that daft man has said daft things
I'm fully aware that I'm at the back of this human centipede of content, but ultimately people get the content they deserve.

Back on a Swans focus with regards to Giggs, he was being reported as possible target as early as Sep 21st in this Telegraph piece with Huw Jenkins apparently keen but the new owners less so, fast forward a few weeks and Rory Smith's article in the New York Times is almost falling over itself to stress how much Bradley is Huw's man:

It is Bradley’s job to quell that doubt and disprove that charge. He has started well. Of the three who conducted the interviews, it was Jenkins — Welsh through and through — who was arguably most impressed by the American, won over by the range of his experience and the clarity of his vision. Bradley still has questions to face, but Jenkins, for one, is convinced he will find the answers.

It may well be that Bradley impressed more than Giggs at interview (given Bradley's first press conference, there's no doubt the guy likes to talk), but the thing that concerns me earlier is that earlier in that Rory Smith piece a source at the club is perfectly happy to insinuate that one of the other interviewee's (presumably Giggs) basically just said that the players need to run around more.

It's easy to laugh at that, but coupled with their lack of communication with the Trust and the fact that they are currently using Talksport rather than other channels to speak to the fan base still leaves a lot of questions about their behaviour.

For more on the new owners, there's an earlier piece here, and also one on the old board and the Swans Trust.

Tuesday, 4 October 2016

Swans review pt2 - Swans Trust and Old Shareholders

Following on from part 1, where I looked at the background, comments and possible motivations of the new shareholders this part was initially going to be a bit more in-depth but recent events have overtaken that but wanted to get this out anyway:

Old Shareholders

While there's an enormous amount of credit in the bank for the work (and financial input) from the old shareholders there's plenty in the last 12 months to feel aggrieved about.

Although both the sackings of Monk and Guidolin could to differing extents be justified, both were handled pretty badly.

Monk's in terms of making him take training even through everyone knew he was finished and Guidolin for the case of re-hiring him in the summer then pulling the plug effectively after 5 league games and leaving him to deal with the (not-so quiet) whispers of the last couple of weeks.

Being a shareholder at Swansea City in recent times must have been like balancing an uninsured Ming vase on your head: technically you're a rich man but one slip and you're just left with a mess to clear up.

Personally, rather than the 'Taking Swansea to the next level' stuff I'd rather they were honest and said it was a life changing amount of money you can't really say no to and it was time to get out while the going was good.

The fact that the sale went ahead largely without the Trust's knowledge suggests the shareholders didn't want anyone rocking the boat which when you consider the sums of money involved I can understand. It's one thing to say you'd do the decent thing but to be honest in the same situation I'd be tempted to do the same.

It does however leave the question of how much of a selling tool Jack to a King was, given it appears to have been funded by an interest free £1.2m loan from the club, it may be that ticket + DVD sales and other rights bring a decent return and the club breaks even and gets its money back but question is how much of Jack to a King was to promote the Swansea message and how much to help draw in a buyer?  Given the number of messages from the club about how tough things are financially this seems like an expensive vanity project at best.

The Trust
I think the Trust have a pretty much impossible job, although 21% brings some rights and influence ultimately if people don't want to deal with you then you have no way to force them through the normal legal channels.

This from Trust Chairman Phil Sumbler on the Planet Swans forum was interesting and an insight into the difficulties the Trust face, say too much and be accused of washing your dirty laundry in public, or on the other hand risk others thinking you're saying too little and being ineffective.

They are also in the difficult position now of not being in desperate need for members financially in terms of what £10 memberships can bring in when they have several hundred thousand pounds from club dividends and also have to answer the question 'What difference will my membership make if the Trust get ignored?'

Arguably that's precisely the reason the Trust needs a strong membership, this may all end up a fuss over nothing or it could be the start of something quite messy for which a strong and vocal Trust is required. If you want to join, you can sign up online here

Ultimately a large part of what made Swansea City different and in the words of their own marketing 'Not just another football club' has gone.  That doesn't mean that everything will now fall apart, Bradley's not an idiot even if he's not the most inspiring choice, the squad is OK if not great and I'd put us to finish around 14th-16th.

If you wanted to place blame for where we are now I wouldn't put too much of it at the door of the new owners as things stand. It's not time for the burning pitchforks just yet but they've certainly a fair amount of convincing to do.

Saturday, 3 September 2016

Swans review pt1 - The New Owners

For some, the glass is always half full and 'In Huw we trust', for others we're on the fast track to oblivion as the yanks slowly screw us.

As always the reality is somewhere in between, but for me there's no doubt that the amount of spin 'keep the faith' messaging has increased over recent months, although I would agree with Lee Trundle's view that being overly negative can end up impacting the team a hammering v Chelsea next time out and things could get toxic, even if that's being unfair.

In this piece (and subsequent parts) I'll look at the various areas of concern and try and take an objective view, for me neither blind faith or blind panic will get you far.

The New Owners
The biggest problem the new owners have is that while at face value they are saying the right things, these things are also the kind of soundbites that you'd trot out to keep the plebs happy the way a rock band might say this was the best night of the tour.

"We were driving down the M4 and thought they knew how to support a team in Cardiff, but no-one rocks like Swansea!"

For what it's worth I don't think their asset strippers (although they are obviously here to make a profit). A bit like with privatisation, the aim is to exploit inefficiencies and both be more profitable and provide a better service (in the Swans case I guess that'd be consistently 8th-13th with maybe the odd cup run).

If we assume club was valued at £100m, then the controlling stake would have cost £68m.  I've no idea what kind of return an investor would expect given the potential risks but I can't imagine it'd be less than 5% so you'd want to make £4-5m a year on average either through regular payments or by selling the club on in perhaps 3 years time when the next TV deal comes in.

TV Rights have exploded in last 2 rounds of bidding, the new owners will hope competition from Google or other online firms could drive it even further
The term investors has been used for Kaplan/Levien and is both correct and misleading. If I invest in a property, I'm an investor, but you as my tenant may see no difference now that I'm your landlord. Other than putting enough in (if required) to keep the Swans in the Premier League I don't see them putting in their own money just to move the club up a place or two in the league.

There will be some that will say 'Look at Leicester' but by that argument you could say 'Look at Blackburn/Villa/Charlton' or, God forbid, Blackpool.

In their interview with the BBC they talk about being 'faster, smarter, craftier' and while from the outside a lot of clubs look like their being run by monkeys with dartboards, most will be using data in one form or another.

One possible ray of light in this area is that analytics firm 21st Club were involved in the due diligence when buying the club and are a smart set of people (see press release). Although I have no idea how involved they are in our transfer business, this from one of their analysts at the start of last season about Eder made me smile in retrospect given his season (even if he did end up scoring the winner in Euro 2016).

From 21st Club, a basic, 'Reasons to get X' with Eder as an outlier (not in a good way)
The new owners talk about the club no longer being 'a stepping stone', but that to me sounds like a load of nonsense, if Borja for example has a good season then he'll be off somewhere else for £25-30m next season.

There are a few ways to avoid being a 'stepping stone':
  • Become so good that there's nowhere better to go (this is unlikely)
  • Don't sign players where you're punching above your weight, just get those without too much upward potential or ambition.
Bony/Ayew are good examples of players using the Swans as a stepping stone, I don't see being talented, driven and ambitious as a negative.  If you want a player to have a major impact on the team, it's inevitable that those higher up will show an interest, you can't have a team full of 'unsung heroes'.

I'm delighted that Gylfi has stayed, but I'd imagine his contract has more Clauses than a reunion at a Father Christmas training school.

Landon Donovan's role is a bit of a strange one, this quote from that linked interview with him doesn't fill me with the greatest of confidence:

“The new owners met with me a few months back and said this is likely going to happen and admitted that they didn’t know a lot about football and said ‘we know that you know the game and you’re passionate about it, you played at Everton, spent time in world football and sort of understand it a little better, would you be willing to help us, advise us and consult with us on certain things?’ I said yeah, that would be great and that’s something I am certainly open to."

The above sounds a bit like an attempt to get the face of a 'Friendly American' out there to try and placate people rather than a real in-depth involvement (at least for now, especially since first writing this he has now signed up for LA Galaxy).  As I said earlier, sensible ideas and cynical plans look very similar so time will tell, with regards to analytics, Wales Online yesterday reported a revamp of recruitment methods including a more analytical approach.

Subsequent parts (whenever I get round to it) will look at the old board, the team, the transfer window, finances and where we go from here.

Thursday, 2 June 2016

Mark Lawrenson - Smarter than he looks

For a few seasons now, I’ve been amazed that despite the fact that everyone considers his predictions something of a joke, if you’d actually bet on them, Mark Lawrenson’s predictions would be profitable.

This started back in 2012/13 when I was putting together my first ‘Football and Data’ event and wanted to see how accurate a supposed ‘expert’ was and I was staggered to find that Lawro’s predictions would make money.

Considering this season’s predictions would have placed Leicester in 12th (with relegated Newcastle predicted to finish 11th) surely this season would finally show him up as a know-nothing?
Lawro's predictions over the season (via BBC Sport)
Well, actually 2015/16 would have been another profitable season if you’d followed Lawro’s tips. With a £10 stake on each of his 376 predictions, (4 matches were rearranged and not predicted) then you would have made £271 profit.

Odds were taking from Pinnacle's quoted market from the fantastic Football-Data site and Lawro's predictions from MyFootballFacts.  Pinnacle's margin was 2% so picking at random and placing £10 on each of 376 selections an average punter would expect to lose around £75.

As seen in previous seasons this profit was not made by daring longshots but by being willing to sit on the fence and profit from draws which are often overpriced, in relation to the ‘true’ probability more money goes on a win as the typical punter fancies a positive result.

Sometimes a question will be phrased (either to someone or even within their own thoughts as) ‘Who do you think will win on Saturday’ already suggesting you ignore the draw but even if it’s considered as ‘What do you think the result will be’ then sitting on the fence is considered a pretty boring option even if it makes good betting sense.
Yet again it's the draws that bring in the profit for Lawro
Fans of a lot of teams (especially West Ham this season but also Swansea most seasons), feel that Lawro has a grudge and in West Ham's case it does seem as if Lawro had a blind spot to their form, as a Swans fan it's a bit weird to see Lawro predicting us to finish 18th but still making an £80 profit on matches involving us.
Profit/Loss by Team: Total of  this would double count overall profit as counting each match twice
Where some may change their opinion as more games are played, you could probably predict Lawro's predictions would a fair degree of accuracy at the start of the season. It's not the optimal strategy but it does make some sense, rather than chasing the noise and being overly influenced by recent results, Lawro plots a course and stays with it no matter what. Trying to figure when (if ever) Chelsea would come good or Leicester/West Ham finally drop off would have been a hard task.

As he does every season, Lawro keeps his scores simple with 99 of the 101 predicted draws being predicted as 1-1 (which actually is the most frequent occurring draw)
Lawro's Score Predictions - the three in red (2-0,2-1,1-1) being his three main tips of choice
Lawro's advantage comes from him not being afraid of 'being boring', where the bookies love the 'Have a bang on that' kind of punter who blows £10-£20 on an accumulator (which compounds the issue of a bookies margin), profit is usually derived from a large number of small gains (which could arguably just as easily apply to football itself).

Another example of 'Boring Lawro' is his response when asked about his apparent success:

“If I could successfully predict all the results, do you really think I'd be here? I'd be on a yacht in the Caribbean…“

“If I could really seriously predict football results, I would be sitting on my ocean-going yacht, which would be moored off the Bahamas.”