I'm saying that if they are going to use it for offside calls then they have to be sure that VAR can make that call with an acceptable level of precision.
I suspect football will either modify VAR, or change the offside rule again.
Var debate 2019/20
- Thread starter Chi-town blues
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I suspect football will either modify VAR, or change the offside rule again.
you're interpretation of confidence intervals wasn't quite right but your point stands all the same.
i dont know why they dont sit down and get some uncertainty worked out and say "right, here's the offside line, if he's within a 20cm boundary then we can't call it". working that out, of course, is another matter....
James McJohn
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Appreciate I am stating the obvious here, but if there is the 20 cm boundary, surely you are just moving the line and we would end up with the same amount of reviews trying to determine whether someone is 20 or 21cm offside & thus within "Goal stands" threshold
Brightwell Bros.
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You have to, because they are making measurements to determine whether a player is offside.
All measurements are made up to a certain level of precision. What is the precision of VAR? This is a very legitimate question to ask. The rule is that you are offside or onside, and that you can not be level. OK, that's clear, but it only works if you can make that measurement very precisely.
They need to tell the football world what that precision is in order for us to accept it.
When you make a measurement is made, you report its maximum likelihood and a confidence interval within which you can say, with say 95% probability, that the true value lies within those boundaries. From what I understand those boundaries maybe +/- several cm, and not the mm which are really what you need to make VAR work within the existing rules.
This is just a general comment on what is required to assess VAR in relation to offside. There is still the secondary issue of whether football really wants to stop the flow of the game to do this.
The ideal solution is something that is
a) precise and,
b) fast
I believe VAR is neither.
The graph below is an image I took from the Internet to demonstrate a maximum likelihood estimation and a confidence interval which enables someone to say with a confidence level of X percent (typically 95%) that my estimate of the true value of Y is Z +/- a.
a is your uncertainty. What is VAR's uncertainty? I suspect it is unworkable.
Where is the independent study of VAR technology? They've been trialing this for years. but have they analysed it properly? Maybe it has been detailed but its significance has been lost on football people?
Source: https://datumorphism.com/wiki/statistical-estimation/confidence-interval/
Yeah, I agree with you. That's exactly what I'm saying. I preferred it when I could shrug and call the linesperson blind. I'd prefer not to take work with me to the football.
Scaring Europe to Death
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The most compelling argument for VAR was the "clear and obvious" error for City's disallowed goal against Liverpool in the CL when the linesman flagged for offside, despite the cameras proving that the original contact had been provided by a Liverpool player. Liverpool might still have won, but that goal would have made it 2-0 ,with 50 minutes remaining.
I was all for VAR until witnessing the farce after City's first goal at Schalke last season, and the delay over Laporte's original header, which ironically went straight to a Schalke player.
There followed all manner of excuses, but nothing has since changed, including the commentators laughing at fans for celebrating too soon.
I was all for VAR until witnessing the farce after City's first goal at Schalke last season, and the delay over Laporte's original header, which ironically went straight to a Schalke player.
There followed all manner of excuses, but nothing has since changed, including the commentators laughing at fans for celebrating too soon.
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Unfortunately to get rid of VAR, or improve it, this is the way you have to go. The trouble is the people who are best placed to make that criticism do not have the appetite to do it. All they have to do is go to a college, contact a respected expert and commission an article. It's easy work. Then contact PGMOL for their comments. Asa a result VAR would stand or fall.
MillionMilesAway
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I thought that, but I think they'd move towards doing what they do now, and then seeing if that position fell within the allowable range.
that's a good point, so are we saying "offside is offside" down the millimetre? but only if the technology is good enough to call it? or allowing for clear and obvious error stuff?
bobbyowenquiff
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And that's why they will never allow fans to hear the live discussions about decisions. Essentially it's the sort of corruption that happens a lot in big organisations. It is not about brown envelopes of cash but about keeping your head down if you want to succeed.
MillionMilesAway
Well-Known Member
To some extent.
What it needs is the reffing system to be updated. I don't know how they do it elsewhere, but I bet it's more open.
There are ways it might happen:
UEFA/FIFA instruction to be more transparent (they've done it in other areas)
PL pressure as a result of supporter feedback (this includes sponsors reacting to supporters)
There may be others.