Thursday, August 31, 2017

Arsenal's Squad Mismanagement

I am doing a bit of change of pace post today away from stats to look more at Arsenal. In particular there poor squad management and the coming squad rebuilding job.

Here is a look at the current Arsenal Squad and the contract lengths(according to transfermarkt)

I have shown the length of each players deal and the age that they will be in that season. I have also highlighted the peak years (24-28) green and put players over 30 in red.

Arsenal have six senior players out of contract at the end of the season (and it would have been 7 with Alex Oxlade-Chamberlain getting sold yesterday). The running down of contracts for Per Mertesaker and Santi Carzorla make a certain amount of sense. For the rest it is absolutely stupid to hold on to a player this late with no chance of getting a return for them.

This situation is bad but what is worse is that next season a further ten players will be in their last season.

Arsenal are going to be in an even more desperate spot next summer. It will have teams circling looking to pick off our best player plus the team will be further weakened with our two major stars in Alexis Sanchez and Mesut Ozil gone(they aren't extending). Further making things challenging Arsenal are likely to be sitting outside the top four again (52% chance of 5th or worse according to my last simulation) and without champions league football to attract players. Oh and their manager will be in the last year of his contract with questions on the long term direction of the club in question.

A couple of those guys with two years to go on their contracts, like Petr Cech and Nacho Monreal are still solid contributors that would not bring a return in the market so it makes financial sense to keep them around but not extend their contract but these are the exceptions. The other guys above with two years left? Yeah decisions should have been made on them last season whether they had a future or not at the club and moved on while they had good market value.

Well run teams make decisions on these players at this point. If you decide they aren't in the long term plans you can still extract value in the transfer market. If you decide to extend the allure of running down the contract to enter free agency is still three years away so that is a less appealing option.

The other major issue for Arsenal is that for all the attacking talent in the team, they are seriously short in players with promise who are pre-peak or just entering their peak ages to take over for older players.

Beyond Alex Iwobi who is near the first team that looks like they could be a starting player. Sure Reiss Nelson looks promising but he is 17 and doesn't have much first team experience but could get it this year but beyond that? Not much.

Let's play director of football and go through the players with two years left and take a look at them.

David Ospina: He is clearly the second choice and not the ideal long term solution to Arsenal's goal keeping question. 29 this season and two years on his deal. Ideally he would have been sold last season but definitely should have gone this summer. His wages as a starting goal keeper for an international team are probably fairly high for a guy who will start in low importance cup games.

Matt Macey: I have no real opinion on his quality but as the third keeper he is probably on a low wage. Probably behind Emi Martinez in the pecking order. Maybe sell but not really a concern as the third keeper.

Nacho Monreal: A solid player still but not a guy that I want extended. He gets picked out to be exploited by high quality wingers not a convincing center back. He can do a passable job at both positions still against average opponents and wouldn't return much of a transfer fee. Keep for depth.

Mathieu Debuchy: Replaced by Hector Bellerin, Arsenal have been trying to offload him for a the last couple years without success. Really should explore doing an NBA style buy out for him just to get him away from the club.

Aaron Ramsey: A good player who suffers from injury issues and not really fitting into the system. If he is going to stay you probably need to build around him to maximize his talents if you don't want to do that he arguably makes the team weaker when he abandons the midfield to play as a second striker too often.  Arsenal should have made the decision on him last year to sign or extend. With the window over he is going to stick around and be in the same position Ozil, Alexis and Chamberlain were in. I probably would have extended him, switched to a 4-3-3, sold Ozil and brought in more midfield depth and let him do his charging runs but with more cover behind him.

Theo Walcott: Fine player, doesn't fit with how Arsenal play. Sell him as he is running down the contract and getting past the peak years. Probably should have left last year to maximize return and allow for money to be re-invested in a younger replacement.

Oliver Giroud: The guy scores goals and has pretty flicks and layoffs but isn't a starter. Teams were offering transfers in the 30 million range for him and Arsenal should have been ruthless and let him go.

Danny Welbeck: Does everything well expect finish moves to produce goals. However that is important as a striker. With this is clearly a rotation option, I like him and think that he is someone to keep around. The age profile is still good and I would have looked to try to see if his contract could be extended a couple years.

Chuba Akpom: Not rated by the manager. Sell.

After that exercise Arsenal moved on at least four players and bought one out to clear out space on the roster. It also freed up £250,000 £300,000 a week in salaries plus some transfer funds to go to replacements and to allow for money to go to extensions.

Doing this exercise helps the team to clear out players who don't have a clear future, it helps to avoid the issues that Arsenal currently have with the Premier League FFP rules. With Arsenal bumping into the top of the new soft cap in the Premier League it is even more important to maximize the output that you get for the salaries that you pay your squad. In this kind of a situation having a lot of good squad players kills long term roster flexibility. This is also an indictment of Arsenal's commercial department failing to keep up allow for more salary flexibility.

Young players are rejecting Arsenal. The current players plus management have backed Arsenal into a corner with an aging squad with little resale value and contracts running down. There doesn't seem to be a plan for next year let alone one for three or four years down the road.

Things are likely to get worse and it could take years for Arsenal to get out of this whole. We can all hope that this doesn't permanently knock Arsenal down from the top tier of the Premier League.

Friday, August 25, 2017

Premier League Week 3 Projections

Week three of the Premier League is here and even though the transfer market is at the forefront with the window closing there are games to be played and projections to be made.

This week there are even more close match ups and just one game with a team expected to win over 50% of the time.

For Arsenal things could really meltdown for the fans with going to Anfield as underdogs. A second loss in a row plus the expected inactivity on the in goings in the transfer market could see things turn absolutely toxic among the fan base.

Lastly here is the latest full season projections:
Click to enlarge
The title race has tightened up with Manchester City drawing against Everton last weekend combined with Manchester United's second 4-0 win and Liverpool also winning. Arsenal's loss at Stoke saw them drop from second title favorites to the sweet comfort of 4th.

The race for top 4 is incredibly tight, with ten teams with at least a 10% chance of being a part of that group. Chelsea have seen their odds drop the most since the start of the season going from 46.8% pre-season to 38% this week while Manchester United have improved their odds the most going from 45.9% to 61%.

In the relegation battle, there are seven teams with at least a 15% chance of going down. Newcastle have moved to joint worst odds with Brighton after two losses to start the season. Newcastle has seen their relegation odds increase 23% since the preseason projection going from 32% to 55%. If Newcastle can't get at least a point against West Ham at home the season might be in jeopardy of being over for them.
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This article was written with the aid of StrataData, which is the property of Stratagem Technologies. StrataData powers the StrataBet Sports Trading Platform, in addition to StrataBet Premium Recommendations.

Tuesday, August 22, 2017

5 Highest Quality Chances from Premier League Week 2

I really liked how this turned out last week so I am going to go through this again.

These are the top 5 highest quality chances produced in the Premier League this week with the inputs that went into them and the xG for each chance.

5. Richarlison vs Bournemouth




0.60 xG: Shot from feet, from very close range, from open play, classified as a big chance.

Not all high quality shots are pretty, this helps prove it.

4. Ben Mee vs West Brom



0.61 xG, Shot from head, from very close range, from a corner, assisted with a cross, classified as a big chance.

Headers are hard part 1.

3. Phil Jones vs Swansea City



0.65 xG: Shot from head, from very close range, from a set piece situation, assisted with a cross, classified as a big chance.

A beautiful delivery from Juan Mata on this free kick. Headers are hard part 2.

2. Joel Matip vs Crystal Palace



0.65 xG: Shot from head, from very close range, from a set piece situation, assisted with a cross, classified as a big chance.

Headers are hard part 3.

1. Eric Bailly vs Swansea City



0.79 xG: Shot from feet, from very close range, from a corner, classified as a big chance. 

This is probably underestimating the chance quality because just getting his foot to the shot pretty much means that this is a goal. For those curious Paul Pogba's free header that was saved was a 0.25 xG shot.

Friday, August 18, 2017

Premier League Week 2 Projections

Week two of the Premier League is here and I have a fresh batch of projections.
This week there are many more close match ups and just a pair of odds where teams would be expected to win over 50% of the time compared to four last week (not including two matches at over 49%). 

The marquee match of Tottenham vs Chelsea shows Spurs as the clear favorites and that doesn't even take into account the players that will be out for Chelsea. It will be interesting if Antonio Conte can pull some magic out of the hat in that match. The midfield that he picks sure will be interesting. 

For Arsenal they are away at Stoke and have pretty favorable odds. My gut would not put things that high up but this week Arsenal should hopefully have more senior players available to play at center back and hopefully Alexis back to at a minimum the bench. I also hope the Oliver Giroud continues as a sub, he is so good at that and really changes the game against tired defenses but really messes with the offensive flow as a starter.

Lastly here is the latest full season projections:
Click to enlarge
Manchester City saw their title odds improve 5% after the results of last weekend to be the biggest gainer, while Chelsea lost nearly 4% with their shocking defeat against Burnley. Arsenal have slipped their way into the second highest average points spot but there is such a narrow grouping among the top teams that will probably switch quite a bit as the early season plays out.

In the relegation fight, Burnley were huge movers going from 45% relegation to 30% relegation with a win against the defending Champions with Huddersfield getting a 9% bump with their opening win. Crystal Palace were the big dropper of the week and could be in serious trouble with starting the first two matches with 0 points and real danger lurking with a trip to Anfield.

Also the rest of the big leagues will be kicking off this weekend. For those that follow my stats I want to give an update on my updating schedule. I usually update the Premier League first on Monday morning Pacific Time and then get the rest of Europe as team permits and that some times stretches into the week. I try to get all the stats updated by the time that games kickoff for Fridays but I will try to have it done earlier than that.
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This article was written with the aid of StrataData, which is the property of Stratagem Technologies. StrataData powers the StrataBet Sports Trading Platform, in addition to StrataBet Premium Recommendations.

Wednesday, August 16, 2017

Napoli vs Nice First Leg Champions League Playoffs Simulation

After the thrilling Hoffenheim vs Liverpool playoff matchup yesterday, today we have the second of the big match up in the playoffs to get to the group stage of the Champions League in Napoli vs Nice.

My simulation model (which I think I will go into depth on as tomorrow's post) thinks that Napoli is a big favorite to win this match. I should also point out that Nice's stats are really pretty mediocre and that they rate on stats as a midtable French team but last season they really overperformed and finished in third.

The Nice coach Lucien Favre has a bit of a track record in doing this for the teams that he coaches.



Tuesday, August 15, 2017

5 Highest Quality Chances from Premier League Week 1

*Note I am not sure if this will be a reoccurring item or not but I thought I would at least give it a shot for week 1 and see if I like how it turns out.*

These are the top 5 highest quality chances produced in the Premier League this week with the inputs that went into them and the xG for each chance.

5. Mohamed Salah vs Watford


0.6 xG: Shot from feet, from very close range, classified as a big chance.

That pass by Roberto Firmino really makes this goal. Holly crap that was nice. 

4. Shinji Okazaki vs Arsenal


0.61 xG: Shot from head, from very close range, from a corner, assisted by a headed pass, classified as a big chance.

That's some poor goal keeping.

3. Stefano Okaka vs Liverpool


0.61 xG: Shot from head, from very close range, from a corner, assisted from a cross, classified as a big chance.

2. Miguel Britos vs Liverpool


0.61 xG: Shot from head, from very close range, from a corner, regular assist, classified as a big chance. *Also offside

1. Romelu Lukaku vs West Ham


0.82 xG: Shot from foot, from the center of the box, following a fast break, assisted with a through ball, classified as a big chance.

Marcus Rashford did most of the hard work for this goal with his run and beautiful through ball.

Hoffenheim vs Liverpool First Leg Champions League Playoff Simulation-Updated with Full Time Stats

 

Liverpool kick off their Champions League campaign with one of the harder draws of the round. As a neutral observer I am excited for this match.

Liverpool should be favorites even without Phil Coutinho in this match but it could still be a close affair when the match switches to Anfield. Liverpool also have a very good chance, I put it at 90% of getting at least 1 all important away goal tonight.

I look forward to having the Champions League back.
--Update 8/16/17--
Here are the full time xG stats and the xG chain from the match

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This article was written with the aid of StrataData, which is the property of Stratagem Technologies. StrataData powers the StrataBet Sports Trading Platform, in addition to StrataBet Premium Recommendations.

Monday, August 14, 2017

My xG models

I as re-start my weekly updates of the stats that I post on Tableau I wanted to get around to writing about my different xG models.

I have already written about where I get my data from (although that doesn't include StrataBet data but that isn't in the xG model right now or any of the stuff on Tableau) and wanted to go into depth on how these numbers are derived.

First is that I have 4 different xG models, they each vary slightly and are dependent on the information at hand. They are all derived using a logistic regression based on Premier League Data from 2015-16 and the big 5 European leagues + Champions League from 2016-17.

The first and most used is what I started out calling Chance Quality last season and then gave up and realized that name will never catch on and switched to following everyone else calling it xG. In Tableau this will be labeled xG.

Here is the formula for this:

(1-(1/(1+((e^(-2.5+(Feet*-0.29)+(Head*-0.71)+(Very Close Range*1.28)+(Six Yard Box*0.39)+Center of the Box*0.45)+(Wide Box*-0.24)+(Outside Box*-0.86)+(Long Range*-1.09)+(More than 35 Yards*-1.59)+(Difficult Angle*0.16)+(Set Piece*0.88)+(Direct Free Kick*1.91)+(Corner Kick*0.71)+(Throughball Assist*0.31)+(Cross Assist*-0.25)+(Headed Pass Assist*-0.28)+(Fast Break*1.59)+(Opta Big Chance*1.94)

All of the variables are either 1 for yes or 0 for no. It is in the simplest taking a look at where a shot was taken based on fairly large sized buckets. Was it set or open play, how was it assisted and was it a fast break or big chance. Overall I have found that this pretty accurately reflects the work done by others and gives numbers that are very reasonable.

The next xG model is looking at Shots on Target which uses the same variable as above but it is based on only shots on target (for this it is very simply saved shots or goals no blocks). I created this because I believe that shooting accuracy is a skill (how much of a skill compared to luck or random variation ¯\_(ツ)_/¯) and also I way to get a rough measure of goalkeepers.

The formula for this is:

On Target*(1-(1/(1+((e^(-1.64+(Feet*-0.54)+(Head*-1.23)+(Very Close Range*1.99)+(Six Yard Box*1.13)+Center of the Box*1.15)+(Wide Box*0.45)+(Outside Box*-0.07)+(Long Range*-0.95)+(More than 35 Yards*-1.28)+(Difficult Angle*0.46)+(Set Piece*1.33)+(Direct Free Kick*1.95)+(Corner Kick*1.32)+(Throughball Assist*0.05)+(Cross Assist*-0.004)+(Headed Pass Assist*-0.37)+(Fast Break*2.78)+(Opta Big Chance*1.33)

The next xG is for when I do not have Big Chance data. Collecting the big chance data is a big pain in the ass, it is very helpful for building the model but it is all collected by hand and it isn't always available at the exact moment. There are also competitions that it isn't published and I wanted to be able to do analysis on those competitions as well. This uses the same variables expect for no big chances.

The formula for this is:

(1-(1/(1+((e^(-2.5+(Feet*0.09)+(Head*-0.46)+(Very Close Range*2.58)+(Six Yard Box*1.18)+Center of the Box*084)+(Wide Box*-.32)+(Outside Box*-1.07)+(Long Range*-1.29)+(More than 35 Yards*-1.8)+(Difficult Angle*0.11)+(Set Piece*0.86)+(Direct Free Kick*1.88)+(Corner Kick*0.51)+(Throughball Assist*1.19)+(Cross Assist*-0.33)+(Headed Pass Assist*-0.29)+(Fast Break*1.9)

The last model is the newest one that I have created and I hope to be able to replace it with the very first one (or even combine the two) and this is used to create the xG Chain stat that I just introduced. This is a very rough model with just six variables but it is good enough that I felt okay publishing and continuing to work on it in the mean time.

The formula for this is:

(1-(1/(1+((e^(-8.26+(Feet*-0.54)+(Head*-1.23)+(X Coordinate*0.06)+(Y Coordinate*0.000074)+(Fast Break*0.93)+(Opta Big Chance*2.37)

At the very least I think that I should be changing the coordinates to distance from center of goal and maybe add the angle. We will see how things work out and I am open to suggestions.

Thursday, August 10, 2017

Premier League Table Simulation- PreSeason



The start of the season is upon us, there is optimism in the air and maybe some dread and anxiety over transfer business not being completed.

With that comes trying to figure out where everyone will finish in the final table. Like many other analysts out there I'll try my hand at projecting the final positions based on a statistical model and simulations. I still have it on my to do list to go more into depth on how explaining my model but here is how I project things to go this year:

Click to enlarge
Manchester City are my favorites like most others, with Liverpool the first of the following pack. After those two the teams are all essentially on the same levels. This bunching of talent could make for an actual title race this season which would be a fun change.

After the big six teams you get Southampton and Everton (who the model doesn't rate nearly as high) followed by a whole bunch of meh teams who all could end up in the relegation battle with the newly promoted teams. Somewhat surprisingly Burnley rates as the 2nd worst team with a 42.7% chance of being relegated.

A quick tangent on the projections, like almost all projection models this one moves teams towards the mean and really flattens the spread of points compared to what will really happen. For example here is the table after one simulation instead of running 10,000.


Team Points Goal Dif
Tottenham Hotspur 77 31
Arsenal 72 32
Liverpool 71 27
Manchester City 70 26
Southampton 70 24
Chelsea 69 22
Stoke City 55 6
Newcastle United 54 -4
Everton 53 1
Swansea City 53 -2
Manchester United 49 9
Crystal Palace 49 -1
Leicester City 46 -16
Brighton & Hove Albion 45 -20
West Ham United 44 -16
Bournemouth 43 -9
Burnley 38 -26
Watford 35 -31
West Bromwich Albion 34 -26
Huddersfield Town 33 -27

It's quite a bit different and looks a lot more like what you would expect from a season expect for being able to win the league with 77 points. I'd to have loved to see Jose Mourinho's meltdown and subsequent firing after his Manchester United finished in 11th place.

Back to the larger sampling of the simulations here is the Title, Top 4 and Relegation odds for the season:
Here is another way to look at the teams, looking at the spread of outcomes with the box and whisker plot.
Click to enlarge
Surprisingly Arsenal have the 3rd highest median points total but they have one of the smallest point spreads among the top 6 teams. I would imagine that this comes from their focus on producing quality shots at the expense of high volume while the other teams all to various extents look to have more shots.

For example, I have Arsenal breaking the 80 point barrier in just 1.5% of simulations compared to 2% for Chelsea, 3% for Tottenham, 3.6% for Liverpool, 10% for Manchester City and 2.5% for Manchester United.

It should be an interesting season and I will do my best to try to run this simulation every week or so to be able to see how things progress as the season goes.
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This article was written with the aid of StrataData, which is the property of Stratagem Technologies. StrataData powers the StrataBet Sports Trading Platform, in addition to StrataBet Premium Recommendations.