Whitey Grandad

Does anybody know at what stage of an attack the xG calculation is made? Some goal attempts might follow an intricate passing move involving multiple players before the ball arrives at the feet of an attacker. Others might be the result of a long hoof downfield from the goalkeeper. Surely xG cannot be estimated solely on how it leaves the boot of the potential scorer? That would be ridiculous. How are the possibilities of deflections evaluated? What was the xG when Perraud got his feet confused and scored his own goal? If football coaches think that it’s a useful metric then that’s up to them but keep it away from the football public please. As for those figures that kept popping up on screen in the World Cup…. Why?

And virtually every game will be make or break until the end of the season.

According to the FA we’re not on the Tele so it must be as you say. The Emirates FA Cup’s fourth round will take place from Friday 27 until Monday 30 January 2023, and the following ties have been selected for live broadcast by the BBC and ITV in the UK.FRIDAY 27 JANUARY 2023 • Manchester City v Arsenal at 8pm on ITV1, UTV, STV, ITVX and STV PlayerSATURDAY 28 JANUARY 2023 • Preston North End v Tottenham Hotspur at 6pm on BBC One, BBC iPlayer and BBC Sport • Manchester United v Reading at 8pm on ITV4 and ITVXSUNDAY 29 JANUARY 2023 • Brighton & Hove Albion v Liverpool or Wolverhampton Wanderers at 1.30pm on ITV1, UTV, STV, ITVX and STV Player • Wrexham v Sheffield United at 4.30pm on BBC One, BBC iPlayer and BBC SportMONDAY 30 JANUARY 2023 • Derby County v West Ham United at 7.45pm on ITV4 and ITVX Each club involved in these ties will receive £110,000 in addition to any payments from the prize fund of the competition. * All times in GMT

Me too. I’m gutted that we left straight after the whistle and missed them 😢

Thanks both of you for your considered replies. In your first paragraph I would argue that the xGs are not accurately computed. If a striker is scoring more than their expected goals would predict then that tells me that their predictions are wrong. As for Wednesday, if we hadn’t scored those two goals then we would have created other opportunities and these of course would not feature in the final evaluation. I don’t know anyone who watched that game who didn’t think that Saints were in any way lucky to have won it or that we were in any way let off somehow by City’s poor finishing. That Alvarez incident was some way off being a serious chance, the ball was played too far in front of him.I must admit that I don’t remember Haaland ever having a sniff.

This is part of the problem. Any video recording is only ever a poorer version of what is seen by an experienced human with their own eyes. It is lower resolution and is only 2D. I should add here that I spent some time in television equipment research involving studio signal processing and was a UK representative on a European Broadcasting Union committee determining future digital studio standards. I have had technical papers published in relevant publications and presented at international conferences. What you think you see is not what actually happened.

They were still there the last time that I saw him.

I agree completely. It's just that sometimes it seems like there's one ruling for Salah and his mates and another for the rest of us.

I know which I prefer.

Then what is the point of it? I am genuinely interested.

At the time I never considered that to have been a reasonable chance of a goal. Similarly with Alvarez, I could see that the cross was too far away from him for him to get anything solid on the ball. Perhaps this is a difference between watching the game live or watching it on TV, which presumably is what the statisticians do.

That's only of any use if the stats are accurate, representative and objective. Each goal chance is treated statistically as a separate independent 'event' yet this is far from the case. Once a team has gone 2-0 up in a game, no matter how 'unexpected' these goals may have been, they will naturally concentrate on keeping the game tight from then on. This means that they will typically have fewer goal chances as the game progresses. Therefore to sum up all the perceived chances in a game and give each of them an individual probability of success which is then added to the others to give a final xG total for their team is misleading.

It used to be reckoned on one goal for every six chances. Overall.

After my lens replacements I now have better than 20-20 vision but that's not necessary for this game. When was Haaland's 'very good' opportunity?

Same for us. Why would anybody buy something technical from the UK when they can buy it from somewhere else in Europe without all the hassle?

That's not what I saw.

Yes of course, but did xG tell you that or was it the results?

I eventually got around to watching the basic highlights on Sky and something struck me about our 'goal' that was disallowed for offside. There was quite a bit of debate on here recently about whether Salah should have been given offside against Wolves but wasn't because the ball came to him off a player who was considered to have deliberately played the ball before he received it. In our game JWP had a shot on goal which was blocked by a defender who stuck his bum out to deflect the ball as it was going behind him. This was a deliberate action by the player so what is the difference between our game and Liverpool's? No VAR of course.

Well said. Statistics have their place but they have to be used in context. Using statistics you can prove that wind is caused by trees waving their btanches.

It's bollox because the data taht is extracted bears no relationship to what happened on the pitch.

A clue as to what?

But xG is never anywhere close to the actual goals scored, which it should be if it ever meant anything.

Only if you want to think of it as such. The rest of us know that we are on a shit run and don’t need any figures to prove it.

Why is it that xG never comes close to the actually result of a game, even with the benefit of hindsight? Anyone who was at that game on Wednesday will have come away thinking that Saints could well have scored three or four whilst City might have got one. If they were very lucky.

And all the stats put together mean nothing.