Rumble's Slightly Positive Expected Goals Ramble

[Max Wall]

1 minute ago, Wookie said:

Based on historical data of how often shits from certain positions with certain variables are scored.

 

Teams have xG and so do players, good players will consistently have more goals than expected.

Think I've started something here.

[Stadt]

A good explanation of xG and what it can reveal 

http://11tegen11.net/2016/02/21/predicting-league-football-using-xg-and-more/

[Max Wall]

42 minutes ago, Kitchandro said:

Expected goals is a load of shit.

 

16 minutes ago, RumbleFox said:

Thanks for your valuable input. X

Surely that should be output? If it's input, that really is a hospital case, though pills are available on prescription.

[RumbleFox]

3 minutes ago, Wookie said:

A good explanation of xG and what it can reveal 

http://11tegen11.net/2016/02/21/predicting-league-football-using-xg-and-more/

Thanks, explained far better than I could. X

[Captain...]

5 minutes ago, Captain... said:

 

But that only tells us the expected goals, what I find interesting is  expected goals vs actual goals, https://talksport.com/football/expected-goals-stats-experts-reveal-how-premier-league-matchweek-four-games-should-have?p=4

Have a look at how the weekend's matches should have finished, the relevant fixture being Leicester city 1.4 Chelsea 0.83 rounding would mean 1-1, but it shows we created he better chances, although this is probably skewed by the penalty.

The other interesting result is Burnley 0.28 vs palace 1.98 (real result 1-0 Burnley) Palace should have scored a couple with the chances they had, so it gives an indication that they were unlucky to lose. The problem with this as a statistical measure is Burnley scored early and then shut Palace out whilst not offering much in the way of going forwards, so their xG would have been higher had Palace scored or Wood missed and forced them to be more attacking.

[Crinklyfox]

5 minutes ago, Wookie said:

A good explanation of xG and what it can reveal 

http://11tegen11.net/2016/02/21/predicting-league-football-using-xg-and-more/

Thanks, the author has made a number of assumptions in order to make this work but it is interesting nevertheless.  The data from the 2015-16 season gave Man U a 50% chance of winning the title and City 12%, which is higher than I imagined.

[RumbleFox]

5 minutes ago, Captain... said:

The other interesting result is Burnley 0.28 vs palace 1.98 (real result 1-0 Burnley) Palace should have scored a couple with the chances they had, so it gives an indication that they were unlucky to lose. The problem with this as a statistical measure is Burnley scored early and then shut Palace out whilst not offering much in the way of going forwards, so their xG would have been higher had Palace scored or Wood missed and forced them to be more attacking.

Agree completely, there are so many different factors involved that it is difficult to place exact "usefulness" on the data other than "that's interesting" but I would be more worried if we were bottom on XG. X

[Woof]

Lots of good explanations of "expected goals " as referenced above.  The term is a bit confusing if you are not into statistical analysis where "expected"  just means average - so it is based on the average number of goals scored over a large number of games from different situations and positions.  Expected goals and actual goals will of course be a lot closer over a whole season than just 4 games.

 

I don't think they include a Sclupp factor - who is actually taking the shot 

[JerryLundegaard]

I'm quite a fan of the expected goal metric as it happens.  I know that some people don't like it, but it is not just like they pluck the figures out of thin air.  I don't think it would have come to the fore in the media as it has recently if there was not an accurate statistical basis for it.

 

I think the best way to look at it is as a 'chances created' statistic.  Somebody might say that Leicester had two good chances on Saturday (penalty and Slimani one-on-one).  But that is just somebody's opinion.  XG converts that opinion into a factual statistic.

 

I've not seen the Palace game the other day, but I do know that Palace had 23 shots to Burnley's four, was it?  Now it might well be the case that Palace dominated the game, but considering that only four of their shots were on target, it may also be the case that they had a lot of pot shots from range.  If you introduce the XG angle, that might show that Palace didn't actually create a lot of good goal scoring opportunities, despite having so many shots.

 

(Disclaimer - as I say I've not seen the game, and Palace might have deserved to win, I'm just talking hypotheticals.)

 

With all that in mind, it surely reflects well on us that we are 8th in expected goals scored considering the calibre of opponent we've played so far.  17th in expected goals against is perhaps par for the course.

[JerryLundegaard]

2 hours ago, Captain... said:

The other interesting result is Burnley 0.28 vs palace 1.98 (real result 1-0 Burnley) Palace should have scored a couple with the chances they had, so it gives an indication that they were unlucky to lose. The problem with this as a statistical measure is Burnley scored early and then shut Palace out whilst not offering much in the way of going forwards, so their xG would have been higher had Palace scored or Wood missed and forced them to be more attacking.

I didn't see your post before I added mine re: Burnley Palace game.

 

Burnley may well have shut up shop, but the fact that Palace created roughly two goals worth of chances perhaps shows that Burnley didn't do a very good job of it, and, as you say, Palace deserved to win it.

 

What Burnley can take away from that is that shutting up shop is all well and good, but maybe they need to generate more going forward in games like that in the future. Perhaps think about why their counter attacks weren't working in that particular game.

 

 

[RumbleFox]

3 hours ago, JerryLundegaard said:

I'm quite a fan of the expected goal metric as it happens.  I know that some people don't like it, but it is not just like they pluck the figures out of thin air.  I don't think it would have come to the fore in the media as it has recently if there was not an accurate statistical basis for it.

 

I think the best way to look at it is as a 'chances created' statistic.  Somebody might say that Leicester had two good chances on Saturday (penalty and Slimani one-on-one).  But that is just somebody's opinion.  XG converts that opinion into a factual statistic.

 

I've not seen the Palace game the other day, but I do know that Palace had 23 shots to Burnley's four, was it?  Now it might well be the case that Palace dominated the game, but considering that only four of their shots were on target, it may also be the case that they had a lot of pot shots from range.  If you introduce the XG angle, that might show that Palace didn't actually create a lot of good goal scoring opportunities, despite having so many shots.

 

(Disclaimer - as I say I've not seen the game, and Palace might have deserved to win, I'm just talking hypotheticals.)

 

With all that in mind, it surely reflects well on us that we are 8th in expected goals scored considering the calibre of opponent we've played so far.  17th in expected goals against is perhaps par for the course.

Yeah, I find it an interesting area too.   I think I could get quite into stats but I am too lazy and not very bright.  People seem to get hung up on one side or the other.  People either get lost in stats or you get the whole "yeah but you can prove anything with stats, you play the game on the pitch not a spreadsheet" yet both sides miss the point.  Stats provide one valuable tool in the representation and prediction of football matches (if there was nothing in it at all bookies would not exist) and it seems silly not to even look at them.  Of course sometimes there are outliers and sometimes freaks happen (our title win being one) but over the course of 1000000 matches the stats will get it right more than they do wrong.  I basically started looking into it to try and be less sh1te at Fantasy Premier League and just thought it was interesting from a Leicester perspective.  I really do think we will do OK this season and it's nice to see there is some basis statistically for thinking this.  That said, we could get fvcking tonked on Saturday in which case Statto is getting a fisting.  And, you know, by fisting I mean a punch not my fist up his anus. X

[Bluetintedspecs]

A thread with stats, Babs will be reaching for a box of tissues and some juicy stats

[JerryLundegaard]

2 hours ago, RumbleFox said:

Yeah, I find it an interesting area too.   I think I could get quite into stats but I am too lazy and not very bright.  People seem to get hung up on one side or the other.  People either get lost in stats or you get the whole "yeah but you can prove anything with stats, you play the game on the pitch not a spreadsheet" yet both sides miss the point.  Stats provide one valuable tool in the representation and prediction of football matches (if there was nothing in it at all bookies would not exist) and it seems silly not to even look at them.  Of course sometimes there are outliers and sometimes freaks happen (our title win being one) but over the course of 1000000 matches the stats will get it right more than they do wrong.  I basically started looking into it to try and be less sh1te at Fantasy Premier League and just thought it was interesting from a Leicester perspective.  I really do think we will do OK this season and it's nice to see there is some basis statistically for thinking this.  That said, we could get fvcking tonked on Saturday in which case Statto is getting a fisting.  And, you know, by fisting I mean a punch not my fist up his anus. X

It's funny what you say about being hung up one side or the other - that's a bit like what modern society is like.  You can't have a neutral position, you have to be massively for or totally opposed.  A bit like when Ranieri was sacked - most City fans were sad when it happened, but some would accept the decision as being best for the club going forward.  But the outcry from the anti-sacking media almost forces you to defend your position to such an extent that it makes you feel like you wanted him hung drawn and quartered.

 

Anyway back on topic, relying entirely on stats is of course a fool's gambit.  Wasn't there some stat in the 80s going round that said that one in every nine shots taken resulted in a goal?  So teams were encouraged to just shoot on sight.  Doesn't take a genius to work out why that didn't work.  Point being that stats can certainly act as an aid, but you shouldn't rely on them entirely.

 

Glad you clarified about the fisting aspect - wouldn't want to cause any confusion.

[RumbleFox]

8 hours ago, JerryLundegaard said:

It's funny what you say about being hung up one side or the other - that's a bit like what modern society is like.  You can't have a neutral position, you have to be massively for or totally opposed.  A bit like when Ranieri was sacked - most City fans were sad when it happened, but some would accept the decision as being best for the club going forward.  But the outcry from the anti-sacking media almost forces you to defend your position to such an extent that it makes you feel like you wanted him hung drawn and quartered.

 

Anyway back on topic, relying entirely on stats is of course a fool's gambit.  Wasn't there some stat in the 80s going round that said that one in every nine shots taken resulted in a goal?  So teams were encouraged to just shoot on sight.  Doesn't take a genius to work out why that didn't work.  Point being that stats can certainly act as an aid, but you shouldn't rely on them entirely.

 

Glad you clarified about the fisting aspect - wouldn't want to cause any confusion.

You know, to keep this off topic, I was talking about this the other day and it is completely true.  Not sure if it is a new thing or if it has always been so, but there seems to be no grey recently.  Black and white.  Good and bad.  Win or lose.  It's like the whole "PC gone mad" thing.  People just parrot "PC gone mad" to mean anything, to shut down any kind of argument where they may feel people are infringing on their rights to say something whereas, in reality, of course a lot of PC is a massively good thing.  Some might not be a good thing but people never see the grey, on both sides.  Then, as you say, if someone is going too far one way the tendency is to then argue back and go too far the other.  That is why I come across as a bit of a d1ck on here a lot because people say things like "we are sh1t.  Shakey needs sacking. Gray is a cvnt".  It's mental and I can't help but bite whereas I like to think I would never bite back with a reasonable, balanced argument.  Same with politics, it is WIN or LOSE these days.  No real debate, no compromise.  Just "I win, you lose".

 

Anyway, to get back to the important stuff, I might be tempted on a full on Statto fisting were he to promise to clean out his pipes first. 

 

X