Covid 19 outbreak - arguing about Stats (again)

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Jdsk
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Re: Covid 19 outbreak - arguing about Stats (again)

Postby Jdsk » 23 Nov 2020, 12:37am

Looks to me like a typo. But i don't understand the paper yet.

Jonathan

Jdsk
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Re: Covid 19 outbreak - arguing about Stats (again)

Postby Jdsk » 23 Nov 2020, 11:52am

mjal wrote:How is this possible? Even if all those contacts were indeed uninfected, where are the false positive tests? Even assuming just a 1% false positive rate, the chance of getting zero positives out of 1,174 is less than 1 in 100,000.

Could you be persuaded to recalculate that with a better estimate of the FPR, as above?

Thanks

Jonathan

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[XAP]Bob
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Re: Covid 19 outbreak - arguing about Stats (again)

Postby [XAP]Bob » 23 Nov 2020, 12:40pm

Jdsk wrote:
mjal wrote:How is this possible? Even if all those contacts were indeed uninfected, where are the false positive tests? Even assuming just a 1% false positive rate, the chance of getting zero positives out of 1,174 is less than 1 in 100,000.

Could you be persuaded to recalculate that with a better estimate of the FPR, as above?

Thanks

Jonathan



Is it possible that they simply retested anyone who was positive and they came back negative - resulting in a zero rate after retesting, but the report was diluted in telling?
A shortcut has to be a challenge, otherwise it would just be the way. No situation is so dire that panic cannot make it worse.
There are two kinds of people in this world: those can extrapolate from incomplete data.

Jdsk
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Re: Covid 19 outbreak - arguing about Stats (again)

Postby Jdsk » 23 Nov 2020, 12:44pm

As above, I don't understand the paper yet. I did look to see if those rates could be the result of some self-fulfiiling procedure as you describe, but didn't spot anything.

My current thoughts are that the first statistical anomaly suggested above disappears when a realistic FPR is used. And that the second is a typo.

Jonathan

Psamathe
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Re: Covid 19 outbreak - arguing about Stats (again)

Postby Psamathe » 23 Nov 2020, 1:18pm

I see the Conservative Covid Denial Group are talking about rebelling against stricter tiers because it might impact their £££££ and they want a "cost justification". Any cost justification will be "interesting" particularly what the budget the "cost" against each death and will Care Home "deaths" be cost justified differently to a zero-hours contract worker, etc.

Must confess I find it rather pitiful - not the prospect of the stricter tiers getting through as Labour will (mostly) support them so they'll pass, more sad what is says about people who look on protecting lives as a "cost justification"

Ian

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Re: Covid 19 outbreak - arguing about Stats (again)

Postby Oldjohnw » 23 Nov 2020, 1:30pm

Psamathe wrote:I see the Conservative Covid Denial Group are talking about rebelling against stricter tiers because it might impact their £££££ and they want a "cost justification". Any cost justification will be "interesting" particularly what the budget the "cost" against each death and will Care Home "deaths" be cost justified differently to a zero-hours contract worker, etc.

Must confess I find it rather pitiful - not the prospect of the stricter tiers getting through as Labour will (mostly) support them so they'll pass, more sad what is says about people who look on protecting lives as a "cost justification"

Ian


I note that one of them whose name escapes me (a former chair of the ERG) is threatening the Government with the ECHR. And not a trace of irony.
John

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The utility cyclist
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Re: Covid 19 outbreak - arguing about Stats (again)

Postby The utility cyclist » 23 Nov 2020, 3:54pm

https://www.youtube.com/watch?v=XPzvu_YwXXU go to about 19 minutes, Cummins states that people with such a low amount of potential viral RNA (asymptomatic) that triggers a high cycle PCR (45 cycles as for UK) cannot pass on any infection to others.
This is proven science.
it's those demiers of science and inventors of anti science with a globalist agenda that are causing the world to be taken for a ride, destroying freedoms, killing more people, putting more people into poverty, more people on the streets (funnily enough the homeless don't get covid :roll: )
The numbers from government despite the lies regards cause of death/how people died still prove there is no pandemic, that lockdown/tiers and masks are not only ineffective but massively damaging both from a direct cost of human lives but financially which will cost more lives.
£2 trillion debt now because of the over reaction!

You can forget about the visa's mentioned in the post Brexit thread, you're going to need two tests a week to get a digital health passport and then a vaccine to be able to travel, Quantas have already stated they are going to enforce vaccinations for travellers.
All that for something that poses less threat than flu and people here are gagging for it! :twisted:
Last edited by The utility cyclist on 23 Nov 2020, 6:29pm, edited 1 time in total.

Jdsk
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Re: Covid 19 outbreak - arguing about Stats (again)

Postby Jdsk » 23 Nov 2020, 4:19pm

Two people talking on YouTube isn't exactly scientific evidence. The one with the Irish accent suggests an FPR of "5% up". As above this is way too high. Consequently "90% of all positives being false" is not an accurate description of what's happening in this outbreak.

The uncertainty about transmissibility is valid. But what you actually said was:

The utility cyclist wrote:
thirdcrank wrote:From my layman's dull perspective, if you want to stop anything getting into the country, you don't let it in. As this lurgy seems to have symptomless carriers that's probably harder than it sounds, but doing it from the very start has more chance of being effective than waiting till it's widespread in the destination country. It would also need preparation in the form of regulations and plans being ready in case they were to be needed.

When you say carriers do you mean people who can infect others? Because the long held evidence and more keeps coming out that this is in fact not true at all.

That is that there are no asymptomatic carriers who can infect others.

Do you think that are any asymptomatic carriers who can infect others?

Jonathan

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Re: Covid 19 outbreak - arguing about Stats (again)

Postby Vorpal » 24 Nov 2020, 9:23am

Jdsk wrote:Two people talking on YouTube isn't exactly scientific evidence. The one with the Irish accent suggests an FPR of "5% up". As above this is way too high. Consequently "90% of all positives being false" is not an accurate description of what's happening in this outbreak.

The uncertainty about transmissibility is valid. But what you actually said was:

The utility cyclist wrote:
thirdcrank wrote:From my layman's dull perspective, if you want to stop anything getting into the country, you don't let it in. As this lurgy seems to have symptomless carriers that's probably harder than it sounds, but doing it from the very start has more chance of being effective than waiting till it's widespread in the destination country. It would also need preparation in the form of regulations and plans being ready in case they were to be needed.

When you say carriers do you mean people who can infect others? Because the long held evidence and more keeps coming out that this is in fact not true at all.

That is that there are no asymptomatic carriers who can infect others.

Do you think that are any asymptomatic carriers who can infect others?

Jonathan


The evidence on this seems to be mixed. The most common result of studies seems to be that people who test positive and do not become symptomatic are somewhat less likely to transmit the virus. But lower transmissibility does not mean zero transmissibility.
“In some ways, it is easier to be a dissident, for then one is without responsibility.”
― Nelson Mandela, Long Walk to Freedom

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Re: Covid 19 outbreak - arguing about Stats (again)

Postby kwackers » 24 Nov 2020, 9:26am

Vorpal wrote:The evidence on this seems to be mixed. The most common result of studies seems to be that people who test positive and do not become symptomatic are somewhat less likely to transmit the virus. But lower transmissibility does not mean zero transmissibility.

Which is exactly what common sense would tell you.

Respiratory viruses and bugs like us to cough, it propels them nicely on their way to infecting the next person.
If you test positive the virus is obviously present, not coughing simply means you're not projecting it but it still has other ways of transmission.

Jdsk
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Re: Covid 19 outbreak - arguing about Stats (again)

Postby Jdsk » 24 Nov 2020, 9:29am

That's why I asked it that way. That issue of transmissibility is interesting and needs investigating, and that's happening.

But a straight answer to "Do you think that are any asymptomatic carriers who can infect others?" would be very helpful in assessing the effort that should go into subsequent discussion. There are people who think that the virus doesn't exist, or that it doesn't cause disease etc.

Jonathan

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Re: Covid 19 outbreak - arguing about Stats (again)

Postby thirdcrank » 24 Nov 2020, 9:31am

And there are people who believe the concerns should be proven beyond all doubt before they are acted on. ie |Reasonable suspicion isn't enough for them

mjal
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Re: Covid 19 outbreak - arguing about Stats (again)

Postby mjal » 24 Nov 2020, 3:01pm

Jdsk wrote:
mjal wrote:How is this possible? Even if all those contacts were indeed uninfected, where are the false positive tests? Even assuming just a 1% false positive rate, the chance of getting zero positives out of 1,174 is less than 1 in 100,000.

Could you be persuaded to recalculate that with a better estimate of the FPR, as above?

Thanks

Jonathan


We are normally on the same side in this debate...

Your quotation implies that the words related are mine ; they are NOT and neither are the figures. They are part of a quote from a comment below the article in Nature ; the said quote was clearly delineated by me.

I did muse about FPR in my long post and made the point that some virologists maintain that there are no "false positives" in the conventional sense and that any generated are due to contamination, clerical error etc. I then went on to say that I had seen a rate of 0.5% offered. I made no claim as to the accuracy of this figure.

I was wrong to say that the paper made no mention of "false positives". There is a reference just beneath Fig 2. but no rate is suggested.

The article gives a resounding "well done" to the whole concept of lockdown and to the Wuhan experience in particular ; I just hope that it is true. Could the UK/Europe/USA have done the same? There were/are sufficient deniers/refuseniks with our milder versions...

Mike.

Jdsk
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Re: Covid 19 outbreak - arguing about Stats (again)

Postby Jdsk » 24 Nov 2020, 3:09pm

mjal wrote:Your quotation implies that the words related are mine ; they are NOT and neither are the figures. They are part of a quote from a comment below the article in Nature ; the said quote was clearly delineated by me.

I'm sorry if I misquoted you. But I've just looked again and the section above that is in quotation marks. The section below has closing but opening question marks. That section has no quotation marks:

...

Here is a quote from the comments below the Nature paper :

""There were no positive tests amongst 1,174 close contacts of asymptomatic cases."

How is this possible? Even if all those contacts were indeed uninfected, where are the false positive tests? Even assuming just a 1% false positive rate, the chance of getting zero positives out of 1,174 is less than 1 in 100,000. In the "source data" section, there's an even more improbable claim: zero positive results out of 85,884 tests conducted in East Lake Scenic Area of Wuhan.

Isn't this clear evidence that the data being used is unreliable?"

...

That's why I thought that it was you speaking.

Jonathan

Jdsk
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Re: Covid 19 outbreak - arguing about Stats (again)

Postby Jdsk » 24 Nov 2020, 3:14pm

mjal wrote:I did muse about FPR in my long post and made the point that some virologists maintain that there are no "false positives" in the conventional sense and that any generated are due to contamination, clerical error etc. I then went on to say that I had seen a rate of 0.5% offered. I made no claim as to the accuracy of this figure.

Do you now accept Spiegelhalter's logic that the FPR in the UK this summer must have been much lower than this?

Jonathan