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The LBW Umpire Referral Flaw

Dan

Hall of Fame Member
Not sure if it was posted, but the margin of error, due to the middle of the ball having to hit inside the middle of the stump, is 5.4 cm (a bit more than 2 inches). Whether this is too large, is arbitrary, not?
Yeah I agree this is too large. Any part of the ball impacting inside the middle of the stump is sufficient; not this half of both rubbish. It makes the margin of error too large.
 

Daemon

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I swear I made an edit to my earlier post bringing up just what Dan said but I guess it didn't go through.
 

TheJediBrah

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The margin of error has come from the people, who make hawkeye though hasn't it? They'd know more what the margin of error is on their own system than somebody watching would.
No. The margin of error currently in use is ultra-conservative.

Regardless of what you try to say, under the current system, umpires call means there is not the evidence to prove the umpire wrong so therefore there is no evidence that the decision is wrong.
*facepalm*

That's the point. Repeating yet again: Under the current system, good reviews of incorrect decisions (even if close), can be left as incorrect decisions and the reviewing team (even though they are correct) can lose their review.

That's the issue. Even though it's a small one in the grand scheme of things, and the current review system as it stands is infinitely better than what we had without it (and still do have in India series).

Does the margin of error change based on the amount the ball has left to travel?
No. The only concession in the system to distance left to travel as a factor is that if it's greater than 2.5 metres (I think) it's automatically not out (or Umpire's cal, I can't remember.)

I could be wrong but I'm pretty sure that's it.
 
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Maximas

Cricketer Of The Year
And let's face it, given that the overarching tradition of cricket decision making is "benefit of the doubt to the batsman", it's a lot easier to cop a ball just fractionally clipping off stump not being given out, than it is a ball just fractionally missing off stump being given out. And having the edge of the on-screen stumps double as the edge of the margin-of-error zone makes actually displaying the margin of error a hell of a lot easier -- less floaty lines in the air required to denote the outside edge of the margin of error as well as the edge of the 'strike zone' and the on-screen stumps themselves.
No this just doesn't follow for me, in the early days of DRS I found it just as difficult to cop a ball quite clearly taking a decent chunk out of off stump being given not out as I think I would a ball missing being given out. In any case, while the 2 other points about benefit of the doubt going to batsmen and DRS being simplified from a viewers perspective are fair, I'd argue if that it should either be 100% trust in the technology and doing away with 'umpires call' entirely or 'umpires call' applies to both the outside half of the stump and its immediate vicinity, both ways are fair rather than this system that isn't consistent. My preference being the tennis style 100% confidence in the technology.
 

Lillian Thomson

Hall of Fame Member
Tennis has to be all or nothing by definition as it's not having to predict a path the ball has been blocked from taking.
 

Maximas

Cricketer Of The Year
I used tennis as an example to illustrate my point rather than to make a comparison but ultimately in cricket a decision one way or the other is made and I don't think 'umpires call' really achieves anything in terms of decision making, and nor do I think the original decision made by the on-field umpire is relevant once technology is called for, therefore I've come to my conclusions
 

Red

The normal awards that everyone else has
Will the pink balls used for night tests be smaller than the red ones as per your diagram, Dan?
 

marc71178

Eyes not spreadsheets
No. The margin of error currently in use is ultra-conservative.



*facepalm*

That's the point. Repeating yet again: Under the current system, good reviews of incorrect decisions (even if close), can be left as incorrect decisions and the reviewing team (even though they are correct) can lose their review.

That's the issue. Even though it's a small one in the grand scheme of things, and the current review system as it stands is infinitely better than what we had without it (and still do have in India series).



No. The only concession in the system to distance left to travel as a factor is that if it's greater than 2.5 metres (I think) it's automatically not out (or Umpire's cal, I can't remember.)

I could be wrong but I'm pretty sure that's it.
How do you know more about the workings of hawkeye then the people who provide it? The margins are there for a reason.

As for something being a good review, based on what? The ****ing prediction doesn't call it a good review as it doesn't prove the umpire wrong.
 

TheJediBrah

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How do you know more about the workings of hawkeye then the people who provide it? The margins are there for a reason.

As for something being a good review, based on what? The ****ing prediction doesn't call it a good review as it doesn't prove the umpire wrong.
I can't really respond without repeating what's been said a dozen times already.

What you've said is just plain wrong.
 

Lillian Thomson

Hall of Fame Member
Yeah I agree this is too large. Any part of the ball impacting inside the middle of the stump is sufficient; not this half of both rubbish. It makes the margin of error too large.
What are you basing this opinion on though? Presumably during trials they've sent down hundred's of thousands of deliveries at stumps without a batsman at the crease and Hawkeye has been shown to be capable of being wrong to that degree. That being the case they have to use this worst case scenario as the benchmark otherwise they can't be 100% sure that the umpire was wrong.
 

TheJediBrah

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What are you basing this opinion on though? Presumably during trials they've sent down hundred's of thousands of deliveries at stumps without a batsman at the crease and Hawkeye has been shown to be capable of being wrong to that degree. That being the case they have to use this worst case scenario as the benchmark otherwise they can't be 100% sure that the umpire was wrong.
I think this might be an incorrect assumption, or at least misleading.
 

Dan

Hall of Fame Member
No this just doesn't follow for me, in the early days of DRS I found it just as difficult to cop a ball quite clearly taking a decent chunk out of off stump being given not out as I think I would a ball missing being given out. In any case, while the 2 other points about benefit of the doubt going to batsmen and DRS being simplified from a viewers perspective are fair, I'd argue if that it should either be 100% trust in the technology and doing away with 'umpires call' entirely or 'umpires call' applies to both the outside half of the stump and its immediate vicinity, both ways are fair rather than this system that isn't consistent. My preference being the tennis style 100% confidence in the technology.

Given that you've just said that the Umpire's Call zone is too large (which I agree with), why on earth would you want to double it's size to make it a full stump-width zone of uncertainty?

At the moment the black box that I've been calling the "strike zone" is the area in which they are certain that the ball would have hit the stumps and removed the bails. Anything outside that zone and you get some degree of uncertainty -- be it margin of error, too close to call, what if it clips and the bails don't fall, what if this completely ****s up how cricket works, or whatever. If not for the half ball-width requirement, it actually makes perfect sense -- the problems arise when you apply the margin of error twice and get ludicrous scenarios when off stump would have been cartwheeling to fine leg but it's apparently 'too close to call'.

In that regard, the stumps shown on the screen are completely irrelevant to the actual DRS calculations. I mean, the broadcasters could do a McDermott and scale down the stumps slightly to centre the margin of error zone around the edge of the stump, leaving the 'strike zone' and the edge of the Umpire's Call zone exactly where they are now, and it achieves your purpose without doubling it's size. But it makes the actual visual component of DRS crazily confusing -- you have to add lines around the outside of the stumps to denote where the 'Umpire's Call' zone ends, and given that Third Umpires don't seem to be capable of understanding how a video actually works yet, I think the simpler the display looks the better.


The other option is to use the stumps as the stumps -- apply no margin of error/uncertainty factor to them -- but to apply that margin of error to the ball. If, with the ball travelling seam-up on the projection, the stitching of the ball isn't impacting with the stump you go to Umpire's Call. That gives you a solid 20-25mm leeway (the radius of a cricket ball is about 35mm, the seam area takes up, what, 12mm or so of that?), which is significantly less than the current Umpire's Call factor, but still somewhat larger than the actual Hawkeye margin of error. Half a stump width gives you about 17.5-19mm of leeway, which is why I prefer that method to the ball one -- it's closer to the actual margin of error.


Alright, the dimensions of a set of stumps are 28x9 inches, so 711x229mm

Basically, take the 'strike zone' takes a 8.75-9.5mm zone out of each side (and the top) of the stumps, so you get a functional 'certain' stump size of about 702x220mm -- slightly smaller than an actual set of stumps. The 'Umpire's Call' stumps (i.e. close enough that we're not certain enough to overrule the umpire) would then have a size of 720x229mm, so slightly larger than an actual set of stumps. The real size sits halfway between the strike zone and the margin of error threshold -- so you get your "applied equally" thing.

Now, broadcast graphics.

For the sake of viewing simplicity, scale the on-screen stumps to be the size of the margin of error stumps. Your 'strike zone' sits exactly as it does now in the graphic -- a thin black line running down the middle of the off and leg stumps. That way you can consistently display every margin of error call as "just clipping" in order to simplify it for Average Joe sitting on his couch and, more importantly, the technologically illiterate bloke making the decision in the 3rd Umpires box.

You could also go the other way, and scale the on-screen stumps to the strike zone, so that if it only missed it by that much you get Umpire's Call. But LBWs have generally been made on benefit of the doubt to the batsman, not benefit of the doubt to the bowler, so that option doesn't make as much sense to me.
 

Dan

Hall of Fame Member
What are you basing this opinion on though? Presumably during trials they've sent down hundred's of thousands of deliveries at stumps without a batsman at the crease and Hawkeye has been shown to be capable of being wrong to that degree. That being the case they have to use this worst case scenario as the benchmark otherwise they can't be 100% sure that the umpire was wrong.
The Hawkeye dude claims 5mm accuracy, possibly blowing out to 10mm in certain circumstances. I'm basically advocating for a 15-20mm margin of error, which is still significantly larger than what he claims. A 50mm+ margin of error is seriously taking the piss IMO.

Even if Hawkeye is out by 10mm on those 49% of the ball hitting the inside half of leg stump decisions, there's no doubt in anyone's mind that the bails are coming off.
 

Stapel

International Regular
How do you know more about the workings of hawkeye then the people who provide it? The margins are there for a reason.

As for something being a good review, based on what? The ****ing prediction doesn't call it a good review as it doesn't prove the umpire wrong.

I think the margins currently used are several times as large as the margins suggested by the providers of hawkeye.

Edit: Dan bet me to it.... By nearly 4 hours.

Apparently, the used margins are 10 times as large as suggested by Hawkeye. That's simply not right.
 
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Maximas

Cricketer Of The Year
Given that you've just said that the Umpire's Call zone is too large (which I agree with), why on earth would you want to double it's size to make it a full stump-width zone of uncertainty?
Because I fundamentally disagree with the fact that the technology can be 100% trusted entirely in one instance (ball is missing the stumps) but not in another (ball is clipping the stumps), ideally the area of umpires call isn't doubled but just shifts to the side to encompass a quarter of the stump width on the outside part of the stump and the same amount of space immediately outside it.

You could also go the other way, and scale the on-screen stumps to the strike zone, so that if it only missed it by that much you get Umpire's Call. But LBWs have generally been made on benefit of the doubt to the batsman, not benefit of the doubt to the bowler, so that option doesn't make as much sense to me.
I've always seen this as an aid to on field umpires who make the final decision then and there, when technology gets involved I see no reason for such traditions to be observed,
 

TheJediBrah

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I've always seen this as an aid to on field umpires who make the final decision then and there, when technology gets involved I see no reason for such traditions to be observed,
I agree. Benefit of the doubt going to the umpires original decision makes sense to me. Otherwise the Umpire's decision literally becomes completely irrelevant unless the team has run out of reviews.
 

Maximas

Cricketer Of The Year
Shame doubt only works one way though, hence the old benefit of doubt going to the batsman creeps in
 
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Stapel

International Regular
I agree. Benefit of the doubt going to the umpires original decision makes sense to me. Otherwise the Umpire's decision literally becomes completely irrelevant unless the team has run out of reviews.
Would that be bad? Let's compare things with the run out or stumping. Umpires don't even bother to make a decision before going upstairs. IMHO, it makes sense to do so with LBW's or caught behinds as well.
 

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