[Albion] xG - we're down to 12th

[Bakero]

that makes as much sense as this whole xG malarkey , biggest case of Emperors new clothes in football. Some shots are harder than others, some will go in, some will not. some difficult chances will be scored, some simple tap ins will be missed. Wow, who would ever have thought it.

There are simply too many variables ranging from something as measurable as distance and angle, to something as immeasurable as a gust of wind at the wrong time, and a slippery bit of grass or a flash of sun light in the keepers eyes as a cloud moves out the way.

Its trying to put a certain mathematical value to a subjective idea and that simply doesnt work.

You should probably let clubs around the world know that they're wasting money on their analytics
department.

What's wrong with a clipboard and a cup of Bovril anyway?

 

[SAC]

Dont get all the anti. In the Xg table for 20/21 Albion qualify for Europe and Palace are relegated. What's not to like?

So, it's for people who don't like the real table? Good last season but not very important (at the moment) this season.

 

[nwgull]

You should probably let clubs around the world know that they're wasting money on their analytics
department.

What's wrong with a clipboard and a cup of Bovril anyway?

Not to mention Tony Bloom's sports betting consultancy!

 

[Couldn't Be Hyypia]

You should probably let clubs around the world know that they're wasting money on their analytics
department.

What's wrong with a clipboard and a cup of Bovril anyway?

Nickbrighton and his like are the reason that we have an owner who can afford to lend the club hundreds of millions. Cheers Nick

 

[Richy_Seagull]

Nothing more than a bit of a variance.

 

[Terry Butcher Tribute Act]

I enjoyed the xG Philosophy book that's plugged on Twitter a lot, it's left me a bit more open minded to xG and what it can be used to show.

What was highly irritating last year was that the GPot disciples decided to amplify the relevance of xG, when actually what it was showing was pretty bloody obvious - we weren't conceding much but weren't taking chances either, meaning we were struggling to get up the table.

It is funny that nobody is crowing about xG anymore now ours isn't that 'good'. Why? Because unless you're a gambler or desperate for some confirmation bias, points on the board will always be the most important metric of how a side is doing. And so far this season we are doing very well indeed.

Sent from my SM-G998B using Tapatalk

 

[Harry Wilson's tackle]

xG isn't meant to be predictive.

Which is where so many go wrong with it; they think it's predictive.

I didn't realise that. Given that league tables do not use xG, if xG isn't predictive, what's the point of it? If I want to look at achievement the only thing that matters is points, goals scored and goals conceded. xG has something to do with how many goals we scored in relation to the quality and frequency of chances taken, so is both a measure of the ability to create good chances and the ability to finish good or bad chances. In other words it is a bit like calculating a statistic (xS) that combines the frequency and texture of shits in relation to the frequency and quality of the food earlier eaten.

I just looked up the calculation:

These are the factors that form the basis of expected goals (xG):

Assist type - long ball, through ball etc.
Was it a header?
Was the ball struck with the foot?
Was it a big chance?
Angle of the shot
Distance of the shot
Was it a one-on-one?
Did it occur in open play or a from a set-piece?

It is also a bit like a statistic I used when I was single, xF

This was calculated on the basis of:

How recently I had had a nice haircut
The thoroughness of my ablutions
The appropriateness of my clothes to the context
The number of unattached women in my vicinity
Proximity to an intermingling scenario
Brut or Hi Karate?
Neediness.

I am happy to report that xF was not remotely predictive, either

 

[nickbrighton]

It does seem that there are two schools of thought. Some love xG and its like, others don't. Very little middle ground.

I am firmly in (if the quote above is true ) Maupays camp- Its Bullcrap, others will disagree and think that a good xG is almost more important than scoring actual goals with a bad xG in a match.

I am only looking at this as a tool for the majority of fans, rather than an analytical tool for sports technicians, for us I am yet to be convinced it is anything more than a gimmick that gives pundits something else to waffle on about when they have nothing else to say

Maybe I am missing something, and I am quite happy to have my mind changed, but so far (like win probability) I find it all a bit stating the bleeding obvious, we can all see how unlucky we were last year, we all saw that our players needed to be a bit more clinical, xG did not make that anymore clearer in any way whatsoever

 

[Nobby Cybergoat]

It does seem that there are two schools of thought. Some love xG and its like, others don't. Very little middle ground.

I am firmly in (if the quote above is true ) Maupays camp- Its Bullcrap, others will disagree and think that a good xG is almost more important than scoring actual goals with a bad xG in a match.

I am only looking at this as a tool for the majority of fans, rather than an analytical tool for sports technicians, for us I am yet to be convinced it is anything more than a gimmick that gives pundits something else to waffle on about when they have nothing else to say

Maybe I am missing something, and I am quite happy to have my mind changed, but so far (like win probability) I find it all a bit stating the bleeding obvious, we can all see how unlucky we were last year, we all saw that our players needed to be a bit more clinical, xG did not make that anymore clearer in any way whatsoever

I'm in the same camp as you.

It's the sort of thing that could work in a simpler sport. But with a goalscoring chance, there are so many factors which are impossible to measure that any result you get isn't going to tell you anything you can't see for yourself.

Just off the top of my head. Is the striker off balance? Has the keeper come out? Did he have a clear view of the ball? Was the ball bouncing around or on the floor? Is he being challenged? Is it on his favoured foot? Is he stretching for it? Is the sun in his eyes? does someone have hold of his shirt? is the cross slightly behind him?

If I had time i'd be able to triple that list. It's all stuff you can see as a fan, but can't possibly account for accurately on a spreadsheet.

 

[nwgull]

I didn't realise that. Given that league tables do not use xG, if xG isn't predictive, what's the point of it? If I want to look at achievement the only thing that matters is points, goals scored and goals conceded. xG has something to do with how many goals we scored in relation to the quality and frequency of chances taken, so is both a measure of the ability to create good chances and the ability to finish good or bad chances. In other words it is a bit like calculating a statistic (xS) that combines the frequency and texture of shits in relation to the frequency and quality of the food earlier eaten.

From a coach/manager's and recrutiment team's point of view, it highlights where the most work needs to be done in training and/or what players we should either be looking to drop and spending money on in the next transfer window.

For fans, it's just an interesting stat for those of us that are a bit geeky. It also gives a much better idea of how a game went if you didn't actually get to see it. For example: The possession and shots stats for the Everton game suggest that we had the upper hand. xG however, suggested that Everton were good value for the 2-0 win.

It is also a bit like a statistic I used when I was single, xF

This was calculated on the basis of:

How recently I had had a nice haircut
The thoroughness of my ablutions
The appropriateness of my clothes to the context
The number of unattached women in my vicinity
Proximity to an intermingling scenario
Brut or Hi Karate?
Neediness.

I am happy to report that xF was not remotely predictive, either

I found during my last period of being single that Neediness was a much undervalued factor when calculating xF. It's something that can be hard to consciously control, but if I was out on a Friday with mates and already had a date arranged for the following night then it certainly had an effect on my conspicuous neediness and my success rate was far far higher!

 

[zefarelly]

Stats, pffff

9 out of 12 is all you need to know.

1.105 pg is enough to give us a PL record total.

 

[Audax]

[...] if xG isn't predictive, what's the point of it?

An example was already given in this thread. While we don't know if it was or wasn't a factor in the team's decision making, you can clearly see its value where it (retrospectively) was clearly able to show that Ryan wasn't performing. Onces Sanchez came in, we saw an improvement. Ryan wasn't able to get back into the team and was eventually shipped out. As I say, don't know if the team uses it or not, but it's *plausible* that it may have played a role in identifying the need to make that change.

Also, re: that Maupay quote: IIRC he made it in the middle of his lean spell last season. Of course he labelled it bullcrap - it was making him look bad. Suspect his opinion would shift pretty quick if it was the other way around and making him look a world beater.

 

[Nobby Cybergoat]

An example was already given in this thread. While we don't know if it was or wasn't a factor in the team's decision making, you can clearly see it's value where it (retrospectively) was clearly able to show that Ryan wasn't performing. Onces Sanchez came in, we saw an improvement. Ryan wasn't able to get back into the team and was eventually shipped out. As I say, don't know if the team uses it or not, but it's *plausible* that it may have played a role in identifying the need to make that change.

Also, re: that Maupay quote: IIRC he made it in the middle of his lean spell last season. Of course he labelled it bullcrap - it was making him look bad. Suspect his opinion would shift pretty quick if it was the other way around and making him look a world beater.

Ahhh, so we needed XG to tell us that

 

[nwgull]

Ahhh, so we needed XG to tell us that

Funnily enough, if you go back to the 'should Matt Ryan have saved that?' thread, you'll find that lots of fans couldn't see what he was doing wrong and why he should be dropped - their reason being that he hadn't conceded any obvious clangers. Problem was that he also wasn't making any match-defining, improbable saves either, which xG's historical data expects keepers to make occasionally.

 

[schmunk]

Ahhh, so we needed XG to tell us that

Yes and no - it's merely a tool for guidance.

Ryan storms into Potter's office:

R - "Why am I not in goal tomorrow, you flaming Galah?"

P - "You let in 2 goals last week and that lost us the match"

R - "But they had 25 shots and I only let 2 in"

P - "Yes, but look at each of the shots - they were all very difficult chances and not expected to score; this xG metric gives me a simple way to display that for each shot"

R - "OK, fair dinkum, cobber"


AAAANNNDDD SCENE.

 

[Swansman]

xG can be interesting.

xG cant be interesting four games into a 38 game season.

 

[Audax]

Ahhh, so we needed XG to tell us that

Maybe, maybe not. Think it was getting pretty obvious he was struggling personally, but the xG metric definitely highlighted it and put a number alongside what it was costing us.

Let's not make the mistake of judging the metric in isolation. It is only a data point. It may or may not be used at the club. If it is used at the club, it will be used alongside a lot of other data points. If it isn't used, it will be because they feel they're getting the required data in other ways.

One thing I'm certain of (without actually knowing): they won't be relying only on eyeballs. Eyeballs will play a part, but there will be plenty of data analysis happening as well.

 

[Bakero]

xG can be interesting.

xG cant be interesting four games into a 38 game season.

This.

 

[Bakero]

I'm in the same camp as you.

It's the sort of thing that could work in a simpler sport. But with a goalscoring chance, there are so many factors which are impossible to measure that any result you get isn't going to tell you anything you can't see for yourself.

Just off the top of my head. Is the striker off balance? Has the keeper come out? Did he have a clear view of the ball? Was the ball bouncing around or on the floor? Is he being challenged? Is it on his favoured foot? Is he stretching for it? Is the sun in his eyes? does someone have hold of his shirt? is the cross slightly behind him?

If I had time i'd be able to triple that list. It's all stuff you can see as a fan, but can't possibly account for accurately on a spreadsheet.

Well, that's why the xG for a single shot or a single match doesn't tell you anything particularly useful. It's the pattern that emerges over time that is salient.

 

[Nobby Cybergoat]

Funnily enough, if you go back to the 'should Matt Ryan have saved that?' thread, you'll find that lots of fans couldn't see what he was doing wrong and why he should be dropped - their reason being that he hadn't conceded any obvious clangers. Problem was that he also wasn't making any match-defining, improbable saves either, which xG's historical data expects keepers to make occasionally.

It doesn't matter what fans think. They're mostly not that bright. A decent football manager can see if a player is or isn't performing.