Coronavirus - Modelling Aspects Only

[XFool]

Might be interesting to consider this, particularly in light of Ridley's comments referred to above:

Where the science went wrong

New Statesman

Sage minutes show that scientific caution, rather than a strategy of “herd immunity”, drove the UK’s slow response to the Covid-19 pandemic.

Third, this would have been better understood at the time if the UK had been able to test at volume. Sage’s scientific approach was very data-driven, which would have been fine had the data been readily available and timely. Data suggests the UK is now at the fore in its testing programme but, until late April, it had only patchy information on the incidence and impact of Covid-19.

[swill453]

Twitter thread from Tim Harford referencing a Washington Post article pondering why infections haven't spiked since the loosening of lockdown in Europe.

https://twitter.com/TimHarford/status/1 ... 0096500737

(It's possible to read the article without subscribing).

Scott.

[Sorcery]

I get the impression that Ridley is critical of Ferguson's model, but then everybody is! It's certainly a problem when Ferguson's model produces different results on separate runs, it strongly implies buggy code. Can't really trust any model that is not bug free in that way. It is absolutely basic to be able to get repeatable results.

I've not looked in detail at anybody's model, but I would expect all medium-complexity (or higher) models to be stochastic in nature, i.e. all runs would be different. Low-complexity deterministic models are surely only for kindergarten use ? Higher-complexity models should be both stochastic and recursive.

- dspp

Getting repeatable results is an initial check that the code is correct. Unrepeatable results are a strong indicator that the code is incorrect.
Perhaps accessing memory beyond it's declared dimensions or use of an un-initialised variable, that kind of thing.
Highly complex models whether stochastic or not, should produce repeatable answers. If you want to vary the inputs in a controlled way as in the Monte Carlo method, that's code that sits on top of a model's code that produces repeatable results. However even there unless you are are using genuinely random seeds for random number generation, the results should always be repeatable.

I seem to remember Electronicfur or another user on one of these boards was attempting to check Ferguson's code, who also didn't think that unrepeatable results ought to be tolerated.

[dspp]

I get the impression that Ridley is critical of Ferguson's model, but then everybody is! It's certainly a problem when Ferguson's model produces different results on separate runs, it strongly implies buggy code. Can't really trust any model that is not bug free in that way. It is absolutely basic to be able to get repeatable results.

I've not looked in detail at anybody's model, but I would expect all medium-complexity (or higher) models to be stochastic in nature, i.e. all runs would be different. Low-complexity deterministic models are surely only for kindergarten use ? Higher-complexity models should be both stochastic and recursive.

- dspp

Getting repeatable results is an initial check that the code is correct. Unrepeatable results are a strong indicator that the code is incorrect.
Perhaps accessing memory beyond it's declared dimensions or use of an un-initialised variable, that kind of thing.
Highly complex models whether stochastic or not, should produce repeatable answers. If you want to vary the inputs in a controlled way as in the Monte Carlo method, that's code that sits on top of a model's code that produces repeatable results. However even there unless you are are using genuinely random seeds for random number generation, the results should always be repeatable.

I seem to remember Electronicfur or another user on one of these boards was attempting to check Ferguson's code, who also didn't think that unrepeatable results ought to be tolerated.

OK, get your point if the RND input file is in fact repeatable (or the number of runs gives repeatable characterists). Good luck. regards, dspp

[johnhemming]

There are two issues with the Ferguson model.

The first is whether it actually is any good even if the coding was done well.
The second is how well it was actually coded.

[Sorcery]

There are two issues with the Ferguson model.

The first is whether it actually is any good even if the coding was done well.
The second is how well it was actually coded.

The Gomes paper suggests the Ferguson model needs revision. Found it this evening here :
https://www.medrxiv.org/content/10.1101 ... l.pdf+html

Haven't read it in any depth yet. It's what inspired Nic Lewis to test the hypothesis for himself.

[Sorcery]

There are two issues with the Ferguson model.

The first is whether it actually is any good even if the coding was done well.
The second is how well it was actually coded.

The Gomes paper suggests the Ferguson model needs revision. Found it this evening here :
https://www.medrxiv.org/content/10.1101 ... l.pdf+html

Haven't read it in any depth yet. It's what inspired Nic Lewis to test the hypothesis for himself.

I now realise I may have implied that Gomes was critical of Ferguson. What I meant to say was the content of her paper (assuming it's true) will force a rethink of the science of epidemiology. It's that much of a challenge to existing thinking. Can't blame Ferguson for that necessarily, he is in the same situation as most other epidemiologists.
However found the detailed critique of his code here : https://lockdownsceptics.org/code-revie ... ons-model/

[Itsallaguess]

Satellite images of packed Wuhan hospitals suggest coronavirus outbreak began earlier than thought -

Harvard Medical School study comparing hospital car parks in 2019 to 2018 finds spike in October..

Coronavirus may have broken out in the Chinese city of Wuhan much earlier than previously thought, according to a new US study looking at satellite imagery and internet searches.

The Harvard Medical School research found that the number of cars parked at major Wuhan hospitals at points last autumn was much higher than the preceding year.

It also found that searches from the Wuhan region for information on “cough” and “diarrhea”, known Covid-19 symptoms, on the Chinese search engine Baidu spiked around the same time.

It has led researchers to suggest that the outbreak began much earlier than December 31, the date the Chinese government notified the World Health Organisation of the outbreak.

https://www.telegraph.co.uk/news/2020/06/08/satellite-images-packed-wuhan-hospitals-suggest-coronavirus/



Cheers,

Itsallaguess

[GoSeigen]

https://www.telegraph.co.uk/news/2020/06/08/satellite-images-packed-wuhan-hospitals-suggest-coronavirus/

Wow, the conclusion might be correct but that's an extraordinarily deceptive pair of photos, reminiscent of Trump's inauguration shots...

News Flash! Cars Fail to Park in Uncompleted Car Park!! [And while we're at it let's hide half the cars behind 3D-rendered buildings...]

GS

[servodude]

Wow, the conclusion might be correct but that's an extraordinarily deceptive pair of photos, reminiscent of Trump's inauguration shots...

News Flash! Cars Fail to Park in Uncompleted Car Park!! [And while we're at it let's hide half the cars behind 3D-rendered buildings...]

GS

Is there a variant of Parkinson's Law that applies to parking?

- sd

[dealtn]

Where did the big tower on the right go?

[Mike4]

Where did the big tower on the right go?

I think it's still there.

The second photo is taken from a different place, almost directly over the big tower but slightly beyond, so you are seeing the far side of it at quite a tight angle.

[redsturgeon]

Is it also a possibility that the photos were taken at different times of the day or on a different day of the week? The photos are meaningless as any evidence of what they purport. Although I am open to the possibility that indeed the outbreak began earlier than otherwise thought.

John

[dealtn]

Where did the big tower on the right go?

I think it's still there.

The second photo is taken from a different place, almost directly over the big tower but slightly beyond, so you are seeing the far side of it at quite a tight angle.

Lots of red dots behind both buildings in that case that wouldn't be visible in the first pic in that case. The fact they are presented in that way says more about the agenda of the publisher than it does about the truth in that case.

Not saying his argument isn't right (I don't have evidence either way to form an opinion), but like I say consistently, weak arguments diminish the strength of your argument not augment it.

[Mike4]

Where did the big tower on the right go?

I think it's still there.

The second photo is taken from a different place, almost directly over the big tower but slightly beyond, so you are seeing the far side of it at quite a tight angle.

Lots of red dots behind both buildings in that case that wouldn't be visible in the first pic in that case. The fact they are presented in that way says more about the agenda of the publisher than it does about the truth in that case.

Not saying his argument isn't right (I don't have evidence either way to form an opinion), but like I say consistently, weak arguments diminish the strength of your argument not augment it.

Its not my argument. I'm not making an argument either way.

I'm pointing out how I think you are misinterpreting the different positions of the camera in the two photos.

[dealtn]

I think it's still there.

The second photo is taken from a different place, almost directly over the big tower but slightly beyond, so you are seeing the far side of it at quite a tight angle.

Lots of red dots behind both buildings in that case that wouldn't be visible in the first pic in that case. The fact they are presented in that way says more about the agenda of the publisher than it does about the truth in that case.

Not saying his argument isn't right (I don't have evidence either way to form an opinion), but like I say consistently, weak arguments diminish the strength of your argument not augment it.

Its not my argument. I'm not making an argument either way.

I'm pointing out how I think you are misinterpreting the different positions of the camera in the two photos.

I think you misinterpreted what I am saying (which of course might be my fault). The emphasis should be on the his, that is the person supplying the photos as evidence of the argument about the virus being prevalent following a different timeline. The final clause uses a generic "your". Anybody making an argument should ensure it is based on sound grounds, using sound evidence, the absence of which weakens what might otherwise be a strong case.

I didn't intend to imply it was your argument, and acknowledge you were just assisting me in interpretation of the image.

[Nimrod103]

Nobody has commented yet on the data from Edinburgh & Oxford universities about the source of infection in the UK

https://www.dailymail.co.uk/news/articl ... Italy.html

https://www.bbc.co.uk/news/health-52993734

showing that there were at least 1300 Covid introductions in the UK, with more than 75% coming from Spain, France and Italy. Clear finger of suspicion being pointed at returning holiday makers and school skiing trips. I'm not sure how the borders could have been sealed to keep out such returning residents.

[redsturgeon]

Nobody has commented yet on the data from Edinburgh & Oxford universities about the source of infection in the UK

https://www.dailymail.co.uk/news/articl ... Italy.html

https://www.bbc.co.uk/news/health-52993734

showing that there were at least 1300 Covid introductions in the UK, with more than 75% coming from Spain, France and Italy. Clear finger of suspicion being pointed at returning holiday makers and school skiing trips. I'm not sure how the borders could have been sealed to keep out such returning residents.

Any data on how many infections came in from Madrid for the Liverpool game?

John

[modellingman]

Nobody has commented yet on the data from Edinburgh & Oxford universities about the source of infection in the UK

https://www.dailymail.co.uk/news/articl ... Italy.html

https://www.bbc.co.uk/news/health-52993734

showing that there were at least 1300 Covid introductions in the UK, with more than 75% coming from Spain, France and Italy. Clear finger of suspicion being pointed at returning holiday makers and school skiing trips. I'm not sure how the borders could have been sealed to keep out such returning residents.

Any data on how many infections came in from Madrid for the Liverpool game?

John

The paper itself is here. https://virological.org/t/preliminary-a ... neages/507

The authors draw the conclusion that large sporting events (they do not mention the Liverpool game specifically) were not significant sources of importation.

[Nimrod103]

Nobody has commented yet on the data from Edinburgh & Oxford universities about the source of infection in the UK

https://www.dailymail.co.uk/news/articl ... Italy.html

https://www.bbc.co.uk/news/health-52993734

showing that there were at least 1300 Covid introductions in the UK, with more than 75% coming from Spain, France and Italy. Clear finger of suspicion being pointed at returning holiday makers and school skiing trips. I'm not sure how the borders could have been sealed to keep out such returning residents.

Any data on how many infections came in from Madrid for the Liverpool game?

John

The paper itself is here. https://virological.org/t/preliminary-a ... neages/507

The authors draw the conclusion that large sporting events (they do not mention the Liverpool game specifically) were not significant sources of importation.

Somewhere in those two sources it says there were 1100 football fans visiting from Spain, but that same week there were 30,000 total arrivals from Spain, so the football fans were a small minority. Added to which I think the consensus is that infection outdoors is not significant, though presumably they went to the pubs afterwards.