United and xG (now that Ole is gone will things change?)

Revan

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Off topic but did the AI really beat Sumail and Miracle? Find it hard to believe.
OpenAI's team defeated several top players in it, but lost even against a retired team of professionals in 5 vs 5 despite starting the games stronger (but weren't able to combine the strategies as well as humans). DeepMind's defeated a couple of Grandmasters in Starcraft.

No idea if it was Sumail and Miracle, I don't know them, neither am too much familiar with the game.
 

KM

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OpenAI's team defeated several top players in it, but lost even against a retired team of professionals in 5 vs 5 despite starting the games stronger (but weren't able to combine the strategies as well as humans). DeepMind's defeated a couple of Grandmasters in Starcraft.

No idea if it was Sumail and Miracle, I don't know them, neither am too much familiar with the game.
Hmmph okay not really disagreeing with your initial point but they were heavily beaten by the retired team as far as I know.
 

Revan

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Chelsea won their title in 2016/17 while massively overperforming in that model (according to understat they had 61.80 xG and actually scored 85). It's sustainable over a certain amount of time, but it was indicating that they shouldn't be able to keep this up, which is what happened. If we properly back Ole during the summer and address our weaknesses, then all this regression oppos are hoping for doesn't necessarily need to happen.
Regression will happen anyway, we simply won't reach 102 points next season, but the effect would be much smaller than now.

Simply putting, we are more or less in par with Spurs, Arsenal and Chelsea in quality but are getting better results than City last season (who might well be the most dominating team ever in EPL). You don't need xG to know that, however, they kind of measure how much better we are performing compared to how we should perform. Obviously, it doesn't take into account new signings, improvement of certain players who are still young, or the team learning to play Ole's way.
 

Revan

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Hmmph okay not really disagreeing with your initial point but they were heavily beaten by the retired team as far as I know.
That's what I said. They lost when played 5 vs 5. Each bot was playing better than a human, but not when joining forces. We are still more creative at some tasks. Still.
 

bucky

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It certainly doesn't help, if there are different figures in terms of xG for the same game. Same thing happened against Palace.
 

Paul_Scholes18

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xG struggles really in terms of dealing with confidence and form. We have both now in our attackers. Pogba, Martial, Rashford and now Lukaku have shown great attacking form and so they should overperform xG. I guess over time players will often go up and down. Although a good manager will use good form from players and also lift them in training. Also Ole adapts how we play depending on results a lot which should impact the numbers.

Some managers like say Pep is mainly good at having tactical control in games over 90 minutes using the same style and system, but might not lift up the confidence of his players by good man management. Even when City have 1-2 goals they keep on attacking. It might not always be the best idea, but it often gives them stable numbers over time in terms of xG.
 

Dave89

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It is an extremely idiotic comment. The alternative league table converges to the real table at the end of the season, by definition. How it can be used to feel better when the final tables are in the end the same?
I think we're getting confused here. There was an "alternative league table" that corrected what the scousers saw as injustices. Every time a liverpool player went down in the box without getting a penalty, they added a goal on to the scoreline. Everytime we scored a goal, if we got a questionable throw-in 5 mins earlier, they took that goal off. Then they put these adjusted scores into the league table and declared themselves moral champions. (only a very slight exaggeration on my part there)

The PeterStorey (remember him?) table on here was to compare teams early in the season before everybody met home and away. Basically, the rough premise was that to reach 91 points and win the league, you had to beat the 20th to 11th placed teams home and away (60 points), 10-7th you'd beat at home and draw away (16 points) and the other 5 teams in the top 6 you'd beat at home (15 points) and lose to them away.

When comparing two challengers, you'd start with 0 points, no change if they beat a bottom ten team, minus two if they drew, whereas away to a top club, no change if you lost, +1 if you drew, etc. It had its flaws (and I don't think I've described it perfectly accurately here), but it was an interesting point of comparison after a run of tricky games or a run of easy games.
 

Pagh Wraith

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The top teams outperform their xG numbers but less so than people might think.

Over the last five years the biggest 'over-performers' in the three top leagues are:

Team | Offensive | Defensive

Barcelona | 7.7% | 13.6%
Real Madrid | 11.5% | 7.8%
Atletico | 11.9% | 23.2%
Juventus | 15% | 10.6%
Roma | 2.2% | 10.2%
City | 8.3% | -8.8% (so City have conceded more than they should have)
Spurs | 14.5% | 9.8%
Chelsea | 13% | -9.5%
United | 8.6% | 12.8%

So United's current numbers do look a little inflated given that no other team has 'outscored' their xG by more than 15% long-term.
 
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Revan

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It certainly doesn't help, if there are different figures in terms of xG for the same game. Same thing happened against Palace.
They are models done by different companies. It is machine learning, not some analytic solutions. Some models will be great, some crap, those that crap will disappear, the good ones will be sold for millions to teams.

It is like recommendation systems that Google and Bing might recommend you different things.
 

bucky

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Regression will happen anyway, we simply won't reach 102 points next season, but the effect would be much smaller than now.

Simply putting, we are more or less in par with Spurs, Arsenal and Chelsea in quality but are getting better results than City last season (who might well be the most dominating team ever in EPL). You don't need xG to know that, however, they kind of measure how much better we are performing compared to how we should perform. Obviously, it doesn't take into account new signings, improvement of certain players who are still young, or the team learning to play Ole's way.
Just wanted to make the point that overperforming isn't that big of a deal over a limited amount of time. I was just giving Pogue an answer that it actually isn't that grim. In fact Tottenham are overperforming more so than we are since Ole has taken over.
 

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Factors considered based on 300,000 observations:

  • Distance from goal
  • Angle of the shot
  • Did the chance fall at the player's feet or was it a header?
  • Was it a one on one?
  • What was the assist like? (eg long ball, cross, through ball, pull-back)
  • In what passage of play did it happen? (eg open play, direct free-kick, corner kick)
  • Has the player just beaten an opponent?
  • Is it a rebound?
By definition, a top 4 team (and particularly title winning teams) will have beat the xGs and xGa then, due to better individual players? Just means your players are better and are on form? If you are trending close to average you'll be midtable and if you're below average you'll be towards to bottom end of the table.

It'll be interesting to see how many times title winning teams beat this number.

Even then, depending on playing style, you may find some teams have a normal xG (scored and conceded), but much better xA if there is a stat like that (if you take into account the chance of beating a press, a tackle and creating a chance from midfield). They are just fancy ways of saying a team is better.

Of course, as with any stat if it happens in one game it can be an anomaly. If it happens over 17 (half a league season almost) games, may be there is a different inference.
 

Revan

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I think we're getting confused here. There was an "alternative league table" that corrected what the scousers saw as injustices. Every time a liverpool player went down in the box without getting a penalty, they added a goal on to the scoreline. Everytime we scored a goal, if we got a questionable throw-in 5 mins earlier, they took that goal off. Then they put these adjusted scores into the league table and declared themselves moral champions. (only a very slight exaggeration on my part there)

The PeterStorey (remember him?) table on here was to compare teams early in the season before everybody met home and away. Basically, the rough premise was that to reach 91 points and win the league, you had to beat the 20th to 11th placed teams home and away (60 points), 10-7th you'd beat at home and draw away (16 points) and the other 5 teams in the top 6 you'd beat at home (15 points) and lose to them away.

When comparing two challengers, you'd start with 0 points, no change if they beat a bottom ten team, minus two if they drew, whereas away to a top club, no change if you lost, +1 if you drew, etc. It had its flaws (and I don't think I've described it perfectly accurately here), but it was an interesting point of comparison after a run of tricky games or a run of easy games.
I have been iin RAWK for years, and the only alternative table there has been a similar version (if not identical) to Storey's table. The alternative table which shows that they win the league didn't ever exist in reality (at least not in RAWK). It is just a Mandela effect.
 

Dave89

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I have been iin RAWK for years, and the only alternative table there has been a similar version (if not identical) to Storey's table. The alternative table which shows that they win the league didn't ever exist in reality (at least not in RAWK). It is just a Mandela effect.
Hm, I'm sure I've seen it hosted elsewhere (not actually on RAWK) but until I can find it I'll have to hold off.

Edit - I've found these https://www.theguardian.com/footbal...r-league-table-liverpool-top-burnley-west-ham and https://sportslens.com/right-result/ but neither are what I was actually thinking of.
 

Paul_Scholes18

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The top teams outperform their xG numbers but less so than people might think.

Over the last five years the biggest 'over-performers' in the top leagues are:

Team | Offensive | Defensive

Barcelona | 7.7% | 13.6%
Real Madrid | 11.5% | 7.8%
Atletico | 11.9% | 23.2%
Juventus | 15% | 10.6%
Roma | 2.2% | 10.2%
City | 8.3% | -8.8% (so City have conceded more than they should have)
Spurs | 14.5% | 9.8%
Chelsea | 13% | -9.5%
United | 8.6% | 12.8%

So United's numbers do look a little inflated given that no other team has 'outscored' their xG by more than 15% long-term.
Most of these numbers make sense, but something stand out. Barcelona only 7.7% up with Messi being so good is low. I guess Suarez have missed far too much to reduce those numbers.
Chelsea being so efficient impress me even with not having the most clinical strikers. Although I guess with Costa,Hazard and Mourinho they scored early and then defended a lot. -9.5% for defending is not what I would have expected though given that they have had a solid defense and good keepers.

Pep defends by not giving away too many chances so I can see why they have conceded more goals than expected.
 

Skills

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Found someone who failed in high school.
:lol:

To me it's funny that someone can take so much pride in labeling data and statistics as 'bollocks' in the 21st century. You'd be laughed out of the doors of any competitive business in the world, if this was ever said in a professional environment.

There really isn't a place for data illiterate people in the current and future world.
 

bucky

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They are models done by different companies. It is machine learning, not some analytic solutions. Some models will be great, some crap, those that crap will disappear, the good ones will be sold for millions to teams.

It is like recommendation systems that Google and Bing might recommend you different things.
Nonetheless it can create confusion if you label it all xG. That 11tegen11/between the posts bloke on twitter for example had a figure for our Crystal Palace game, which seemed absurd.
 

LungiDevil

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The top teams outperform their xG numbers but less so than people might think.

Over the last five years the biggest 'over-performers' in the three top leagues are:

Team | Offensive | Defensive

Barcelona | 7.7% | 13.6%
Real Madrid | 11.5% | 7.8%
Atletico | 11.9% | 23.2%
Juventus | 15% | 10.6%
Roma | 2.2% | 10.2%
City | 8.3% | -8.8% (so City have conceded more than they should have)
Spurs | 14.5% | 9.8%
Chelsea | 13% | -9.5%
United | 8.6% | 12.8%

So United's current numbers do look a little inflated given that no other team has 'outscored' their xG by more than 15% long-term.

Do you know these numbers looked in their title winning years instead of a 5 year period?
 

Social Faux Pas

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Factors considered based on 300,000 observations:

  • Distance from goal
  • Angle of the shot
  • Did the chance fall at the player's feet or was it a header?
  • Was it a one on one?
  • What was the assist like? (eg long ball, cross, through ball, pull-back)
  • In what passage of play did it happen? (eg open play, direct free-kick, corner kick)
  • Has the player just beaten an opponent?
  • Is it a rebound?
By definition, a top 4 team (and particularly title winning teams) will have beat the xGs and xGa then, due to better individual players? Just means your players are better and are on form? If you are trending close to average you'll be midtable and if you're below average you'll be towards to bottom end of the table.

It'll be interesting to see how many times title winning teams beat this number.

Even then, depending on playing style, you may find some teams have a normal xG (scored and conceded), but much better xA if there is a stat like that (if you take into account the chance of beating a press, a tackle and creating a chance from midfield). They are just fancy ways of saying a team is better.

Of course, as with any stat if it happens in one game it can be an anomaly. If it happens over 17 (half a league season almost) games, may be there is a different inference.
Not arguing anything you mentioned. Just adding a tangential point that in terms of factors, some models such as Stratabet's model factors in positioning of defenders as well. So results will vary from models to model. I am not sure the model posted by OP factors in defenders. I reckon the models that factor defenders' positioning are better indicators than the ones do not.
 
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Revan

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Nonetheless it can create confusion if you label it all xG. That 11tegen11/between the posts bloke on twitter for example had a figure for our Crystal Palace game, which seemed absurd.
What confusion it is? It has always been like that that some models are good, some are bad, despite trying to do the same thing. It isn't even special to data analytics, Google gained ground cause their search engine was so much better than the others. But all were 'search engines'.

In every industry there are companies who do well and those who do crap. Why people expect that a machine learning model done from different companies based on different data should result in the same product?
 

Pagh Wraith

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Chelsea being so efficient impress me even with not having the most clinical strikers. Although I guess with Costa,Hazard and Mourinho they scored early and then defended a lot.
Most of that stems from the title-winning season 16/17. The other four season I included in the data sample produce numbers very close to xG.
 

bucky

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What confusion it is? It has always been like that that some models are good, some are bad, despite trying to do the same thing. It isn't even special to data analytics, Google gained ground cause their search engine was so much better than the others. But all were 'search engines'.

In every industry there are companies who do well and those who do crap. Why people expect that a machine learning model done from different companies based on different data should result in the same product?
Not mine. I've been defending this stuff for a while.
 

Paul_Scholes18

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Most of that stems from the title-winning season 16/17. The other four season I included in the data sample produce numbers very close to xG.
Yeah I remember them being very efficient under Conte. Very high confidence and just going so strong over christmas. Although would have expected that too when Mourinho won it. When they did struggle in 15/16 I would have expected them to underperform a lot with Hazard and Costa being in poor form.
 

el3mel

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I cringe whenever I see this expected goals shite.

Some can't get that football isn't basketball. You can use stats to analyze everything in Basketball and NBA games but football is a different sport where stats mean feck all most of time, and those who just depend on stats to analyze football are clueless.
 

Pagh Wraith

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Do you know these numbers looked in their title winning years instead of a 5 year period?
To pick some of the biggest outliers:

Team | offensive | defensive

Chelsea 16/17 | 37.5% | -15.3%
United 17/18 | 15.2% | 35.7%
Atletico 17/18 | 15.3% | 38%
Dortmund 14/15 | -12.7% | -25.7%

That was Dortmund's freak season in which they were dead last after 18 games. Infact after 18 games it looked like this: -24.2% | -32.8%. This is the biggest anomaly I can think of. People need to realise that 38 games is not a big enough sample and that is possible for teams to outperform their numbers over a whole season at unsustainable levels.
 
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RasTiaGba

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I don't really agree with the expected goals statistic.

It is basically a one size fits all formula, where approximately 5 shots equal one expected goal.

In real football, players like Lukaku, Messi and CR7 all know that in the Champions League (v strong teams) you get less chances, and are more clinical with shooting.
 

Pagh Wraith

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I cringe whenever I see this expected goals shite.

Some can't get that football isn't basketball. You can use stats to analyze everything in Basketball and NBA games but football is a different sport where stats mean feck all most of time, and those who just depend on stats to analyze football are clueless.
What is clueless is this post. Yes, football is much harder to analyse that way than sports that largely consist of set pieces. But everything can be translated into a number (even Klopp's wind), just because we don't know it yet and the science isn't advanced enough at this point doesn't mean it can't be done. This is really such an ignorant view to hold in the 21st century.
 

Revan

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To pick some of the biggest outliers:

Team | offensive | defensive

Chelsea 16/17 | 37.5% | -15.3%
United 17/18 | 15.2% | 35.7%
Atletico 17/18 | 15.3% | 38%
Dortmund 14/15 | -12.7% | -25.7%

That was Dortmund's freak season in which they are dead last after 18 games. Infact after 18 games it looked like this: -24.2% | -32.8%. This is the biggest anamoly I can think of. People need to realise that 38 is not a big enough sample and that is possible for team to outperform their numbers over a whole season at unsustainable levels.
De Gea and Oblak are two best keepers in the world. Also, Mourinho (not the shit version we get in third year) and Simeone are great at defense.

If you look into good statistical models here, they just quantify what we already know.
 

Pagh Wraith

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De Gea and Oblak are two best keepers in the world.
I totally agree and it explains why Atletico for example consistently outperform their defensive numbers. But even Oblak and de Gea aren't that much better than the average. That was a freak season even by their standards if we look at their long-term averages.
 

Revan

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I totally agree and it explains why Atletico for example consistently outperform their defensive numbers. But even Oblak and de Gea aren't that much better than the average. That was a freak season even by their standards if we look their long-term averages.
Oh, absolutely. I don't watch Oblak every week but last season was a freak season for De Gea.
 

Treble

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To pick some of the biggest outliers:

Team | offensive | defensive

Chelsea 16/17 | 37.5% | -15.3%
United 17/18 | 15.2% | 35.7%
Atletico 17/18 | 15.3% | 38%
Dortmund 14/15 | -12.7% | -25.7%

That was Dortmund's freak season in which they were dead last after 18 games. Infact after 18 games it looked like this: -24.2% | -32.8%. This is the biggest anomaly I can think of. People need to realise that 38 is not a big enough sample and that is possible for team to outperform their numbers over a whole season at unsustainable levels.
Yup, the widespread view that luck and referee mistakes even themselves out over the course of a season is more wrong than right.
 

Pagh Wraith

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Oh, absolutely. I don't watch Oblak every week but last season was a freak season for De Gea.
I would honestly rate Oblak as the best in the world. It's outrageous at times what he saves. Atletico really have been blessed with good goalkeepers. Or good scouting I guess.
 

Pagh Wraith

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Yup, the widespread view that luck and referee mistakes even themsleves out over the course of a season is more wrong than right.
Well, in the long run they do (unless there is a real bias for some reason). That's just not much comfort when you lose the title on goal difference for example. :)
 

Revan

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Yup, the widespread view that luck and referee mistakes even themselves out over the course of a season is more wrong than right.
Absolutely. The luck and referee decisions balance themselves over the course of a decade (proxy for a very long time), but 38 is not a very big number to say so.
 

Pagh Wraith

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One thing I should also mention is that not all (but the better ones do) xG models include what they call 'defensive pressure' which measures how many defenders are between the attacking player and the goal line and how close they are to him. I would think that Atletico for example put more defensive pressure on the shooter than any other top team, meaning that the shots they concede already have a lower-than-average expectation by the time they reach Oblak.
 

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What is clueless is this post. Yes, football is much harder to analyse that way than sports that largely consist of set pieces. But everything can be translated into a number (even Klopp's wind), just because we don't know it yet and the science isn't advanced enough at this point doesn't mean it can't be done. This is really such an ignorant view to hold in the 21st century.
But it's human beings thats involved here. Last year you told me we wouldn't finish second because of xG and around January you said we were nowhere near Spurs and Chelsea for top 4 due to your stats.
So much plays into football be it form, injuries, confidence, fatigue, Ole playing counter attack (concede more chances) to Peps over recycling of the ball that leaves Bournemouth without a shot on goal.
Stats based on football games will never be as complete as you think they are.
 

Pagh Wraith

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But it's human beings thats involved here. Last year you told me we wouldn't finish second because of xG and around January you said we were nowhere near Spurs and Chelsea for top 4 due to your stats.
So much plays into football be it form, injuries, confidence, fatigue, Ole playing counter attack (concede more chances) to Peps over recycling of the ball that leaves Bournemouth without a shot on goal.
Stats based on football games will never be as complete as you think they are.
I don't dispute that. But all of the factors you listed have a number and probability attached. Some of them we just don't know or have no way of accurately measuring them, others we can approximate. When Harry Kane is replaced by Llorente in Spurs' next game we have a rough idea of how that would influence their chances of winning. But Llorente might play a blinder that day (which again has a probability that we can't pinpoint exactly). xG at least is a very useful tool to filter out some of the noise. Nothing more, nothing less. And United's defensive numbers from last year are up there with some of the biggest statistical outliers. This year they have conceded roughly as many as they 'should'.
 

Revan

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But it's human beings thats involved here. Last year you told me we wouldn't finish second because of xG and around January you said we were nowhere near Spurs and Chelsea for top 4 due to your stats.
So much plays into football be it form, injuries, confidence, fatigue, Ole playing counter attack (concede more chances) to Peps over recycling of the ball that leaves Bournemouth without a shot on goal.
Stats based on football games will never be as complete as you think they are.
Of course they are not, it is an idealized model in the end, not real world. It is far better than the traditional stats (number of shots, possession etc) and in the long term a very good model should outperform experts. I would be totally surprised if within 10-15 years a large part of scouts won't be data scientists.

We aren't finishing second too be fair this season, and based in xG over the course of the entire season, we aren't finishing in UCL zone (though now it has become marginal instead of almost no chance of doing it) Since Ole came, I believe that based on xG we finish in top 4, though while if you interpolate the points over the entire season we break City's record of last year, if you interpolate xG, we don't win the league.

I believe that anyone with a functional pair of eyes would agree that we won't win the league if we play like this. We will do better, maybe compete to the end, but right now it is not a title winning team (unless City has a crash) and the team needs some extra quality. xG just reinforces that opinion.