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Alfs 1:21 Sun Jan 21
Expected Goals

I'm seeing this stat flashed up on MOTD. Could someone explain what it means?

D Scully (eire) 12:25 Sun Jan 21
Re: Expected Goals

"Depends on the striker though surely. Like clear cut chances, you give Aguero 10 he is probably likely to score 6 or 7. Carroll on the other hand!!!!"

Well this actually just gives a method of proving Aguero is better than Carroll, if Carroll is only scoring 3 goals from an expected goals number of say 10 then something needs to be looked at.

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The problems when this is discussed come from peoples willingness to brush stats to the side as being silly or nerdy. The whole world is living with cognitive biases that can be picked apart by proof or stats and nobody likes it, we prefer to live in a fantasy world where our opinions matter and debates can happen.

Alex V 12:18 Sun Jan 21
Re: Expected Goals

>>> You don't just have to say a chance is good, you have to assign a precise number to it.

But that number is not subjective. It's provided to you by the data.

Peterboroughiron 11:57 Sun Jan 21
Re: Expected Goals

Subjective or not it is a total load of unnecessary bollocks in my opinion

Mex Martillo 9:27 Sun Jan 21
Re: Expected Goals

Its subjective
Cannot be anything else.
The fact that someone else could make a different classification and get a different result makes it subjective

gph 9:13 Sun Jan 21
Re: Expected Goals

" good chances"

Nothing subjective?

You don't just have to say a chance is good, you have to assign a precise number to it.

Which is completely different to deciding whether a coin's got its head up or down, or counting how many goals there are in a match

Sydney_Iron 3:40 Sun Jan 21
Re: Expected Goals

I used to like the Seagull tally when watching Test Cricket; maybe they could come up with a way of estimating how many Seagulls on any given day in a Test series based on climatic conditions and historical counts? Be as useful as this stat is in football match IMO!!!

Alfs 3:29 Sun Jan 21
Re: Expected Goals

Ah, so it's all about the 'new gold' that is data.

I'm too old for all that OPTA bollocks and can't for the life of me see how it matters. But thanks for explaining it to me.

Alex V 2:48 Sun Jan 21
Re: Expected Goals

>>> Depends on the striker though surely. Like clear cut chances, you give Aguero 10 he is probably likely to score 6 or 7. Carroll on the other hand!!!!

And some players and teams perform ahead of their xG, and some behind.

I think I'm right in saying that broadly speaking the top players tend to simply have more good chances, rather than necessarily being that much more likely to finish them. Aguaro's xG is 15.5, he's scored 16 this season. Carroll's is 1.4 and he's scored 2.

Alex V 2:41 Sun Jan 21
Re: Expected Goals

>>> And that isn't subjective?

Not really, no.

If I choose to look at our results in terms of home and away results, have I been subjective with the data? Not really, it's just choosing how to look at it, the data itself is fixed. SImilarly you can't invent or subjectively affect a higher or lower likelihood of a shot resulting in a goal, because it's based on shot data that is fixed.

If I decide after looking at the data that the chance of heads in a coin toss is 50%, am I being subjective about it? No, I'm just reflecting what the data tells me.

gph 2:31 Sun Jan 21
Re: Expected Goals

Probably a cricket bod, who thinks football isn't dull enough to be a proper sport...

Sydney_Iron 2:29 Sun Jan 21
Re: Expected Goals

Sounds like a load of absolute shit to me.

Who the fuck dreamed this up?

gph 2:29 Sun Jan 21
Re: Expected Goals

And that isn't subjective?

zico 2:29 Sun Jan 21
Re: Expected Goals

Depends on the striker though surely. Like clear cut chances, you give Aguero 10 he is probably likely to score 6 or 7. Carroll on the other hand!!!!

Alex V 2:25 Sun Jan 21
Re: Expected Goals

Barely. It's more a question of how they decide to organise the existing data.

gph 2:19 Sun Jan 21
Re: Expected Goals

The ground rules which are subjective.

Alex V 2:17 Sun Jan 21
Re: Expected Goals

It's not subjective at all, once you've established the ground rules.

gph 2:13 Sun Jan 21
Re: Expected Goals

An overly subjective stat that excites people on the spectrum.

Alex V 2:10 Sun Jan 21
Re: Expected Goals

It's the amount of goals you might expect to be scored based on the chances created.

They basically look at the type of shots and what angle they're taken from, and look at how often that type of shot results in a goal. Then add them all up for the xG.