Actually they shortened the full title, with Cummings and his pal involved the full name of the group is "SAGE and ONIONS"
Brexit, for once some facts.
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Since this broadcast I've hear there has been a massive increase in Domestos abuse!I'm sorry, I shouldn't laugh, but what else can you do?
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Carole Cadwalladr Retweeted
David Beard@dabeard
At least 30 New Yorkers ingested household cleaners in the 18 hours since the president suggested using it to fight #coronavirus
Thirty New Yorkers reported ingesting household cleaners in 18-hour span after Trump’s bogus...
NYC's Poison Control Center, a sub-agency of the city’s Health Department, managed a total of 30 cases of possible exposure to disinfectants between 9 p.m. Thursday and 3 p.m. Friday.
nydailynews.com
..and make them very low cost,as a lot will be needed and affixed to the outside of the coffins.
So we're all stuffed? Or we will be in thyme.
This would have been handled better if the Turkeys hadn't voted for Christmas remember
I was watching an interview yesterday on CNBC with Nassim Taleb probably most well known for his 2007 book The Black Swan. He is an ex options trader and very bright, he made the following comments regarding the wearing of face masks or face covering with regards to prevention of virus spreading.
He said he could not understand why governments all around the world were not making it mandatory in public places to wear face masks or face covering and went on to explain it like this.
If a person is spreading the virus (lets assume unknowingly) but is wearing a mask (lets assume the mask is inefficient and only prevents about 50% of the virus from escaping) then if that person is joined by someone else who is also unknowingly a virus spreader but is also wearing an inefficient mask (lets say 50% efficiency once again). Then the amount of virus that could be spread by these two individuals has been reduced by 75%.
Initially when I heard this, it didn’t sound right, but I have read Talebs book in the past and knew how sharp he was so I thought I would look into this claim. I think he is using probability theory to come up with this 75% number.
Here is a quick reminder of how this works. Imagine you have two fair coins, each coin when tossed has a 50% chance of coming up heads and a 50% chance of coming up tails.
In order to work out the probability of tossing both coins together and getting two heads or two tails then we multiply the two 50% probabilities together. So, we get
0.5 X 0.5 = 0.25
Therefore, there is only a 25% chance of this occurring. Or to put it another way there is a 75% chance of it not happening. This I think is where Taleb is getting the 75% number from.
During the interview he went on to say that if you have more than two people wearing the inefficient masks then it does not take many until you have massively reduced the amount of virus being released.
For example imagine we are in a supermarket and there are 6 virus spreaders present all wearing inefficient masks (50% efficiency). Then the amount of virus that can be spread in the store by these six people will be reduced by :-
0.5 X 0.5 X 0.5 X 0.5 X 0.5 x 0.5 = 0.016 or 1.6% so the amount of virus spread by these six people has been reduced by a massive 98.4% just by wearing inefficient masks.
Can anyone see either something wrong with my math or something wrong with the logic? This all seems like its an absolute no brainer for everyone to be wearing masks or face coverings in public places.
Now I’m certain the scientists advising the government will be well aware of probability theory so is there something Taleb is not taking into account other than Governments being worried that the public may take all the supply of face masks and leave none for health care workers.
Does anyone know how efficient face masks are in preventing the release of the virus? Perhaps the 50% efficiency of masks is too ambitious and maybe they only prevent 20% or less of the virus being released.
I think I have read that simple home-made masks can prevent 80% or more of the virus being released which would make the math work out even better.
Anyone got any thoughts on this?
He said he could not understand why governments all around the world were not making it mandatory in public places to wear face masks or face covering and went on to explain it like this.
If a person is spreading the virus (lets assume unknowingly) but is wearing a mask (lets assume the mask is inefficient and only prevents about 50% of the virus from escaping) then if that person is joined by someone else who is also unknowingly a virus spreader but is also wearing an inefficient mask (lets say 50% efficiency once again). Then the amount of virus that could be spread by these two individuals has been reduced by 75%.
Initially when I heard this, it didn’t sound right, but I have read Talebs book in the past and knew how sharp he was so I thought I would look into this claim. I think he is using probability theory to come up with this 75% number.
Here is a quick reminder of how this works. Imagine you have two fair coins, each coin when tossed has a 50% chance of coming up heads and a 50% chance of coming up tails.
In order to work out the probability of tossing both coins together and getting two heads or two tails then we multiply the two 50% probabilities together. So, we get
0.5 X 0.5 = 0.25
Therefore, there is only a 25% chance of this occurring. Or to put it another way there is a 75% chance of it not happening. This I think is where Taleb is getting the 75% number from.
During the interview he went on to say that if you have more than two people wearing the inefficient masks then it does not take many until you have massively reduced the amount of virus being released.
For example imagine we are in a supermarket and there are 6 virus spreaders present all wearing inefficient masks (50% efficiency). Then the amount of virus that can be spread in the store by these six people will be reduced by :-
0.5 X 0.5 X 0.5 X 0.5 X 0.5 x 0.5 = 0.016 or 1.6% so the amount of virus spread by these six people has been reduced by a massive 98.4% just by wearing inefficient masks.
Can anyone see either something wrong with my math or something wrong with the logic? This all seems like its an absolute no brainer for everyone to be wearing masks or face coverings in public places.
Now I’m certain the scientists advising the government will be well aware of probability theory so is there something Taleb is not taking into account other than Governments being worried that the public may take all the supply of face masks and leave none for health care workers.
Does anyone know how efficient face masks are in preventing the release of the virus? Perhaps the 50% efficiency of masks is too ambitious and maybe they only prevent 20% or less of the virus being released.
I think I have read that simple home-made masks can prevent 80% or more of the virus being released which would make the math work out even better.
Anyone got any thoughts on this?
But it's a plane, our homes don't have the landing and takeoff strip it needs. Many flats don't even have anywhere for a 'copter to land. Routine drone deliveries will never happen, it was always a daft idea, the futurists getting carried away again.
.
I suppose to establish safe distancing, our army would first need to ask the enemy what the maximum range of their best weapon is.
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The governments disapproval of masks is simply a supply and cost issue. They can't get enough and don't want to risk any more costs falling on them.
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I am convinced that home-made masks are sensible.
If you cut down transmission by 10%, it just might make a difference!
Imagine you go to a supermarket and are reasonably near the security person at the door, two shelf stackers, six other shoppers, and the till person. You are an undiagnosed, symptomless person. Worst case, you infect ten people. Wear mask with marginal effect, you only infect nine.
Yes, pretty bad. But that could be one person not going to die, or one ICU stay not needed. To that person, it is an enormous benefit.
I have written on this previously. Distance beats masks everytime. Even the best mask .. excluding the full hazmat gear with pressurised breathing apparatus,which is of course 100% safe, is typically N95 or 95% capture 5% or 1/20 escapes or gets through .
Airborne transmission is NOT significant ..whereas aerosol transmission .. particles in liquid droplets is. These tend to drop to the ground or onto surfaces around a yard away from the person. . Obviously they can travel Futher in air conditioning or wind flow as a plume. Of course others travelling behind could disturb those resting on the ground and bring them back into the air. But plumes are directional and statistically average out .
The intensity or viral load drops off at least as fast as the cube of the distance from the emitter. ..At 3 metres the load is 1/27 that at 1 ,and therefore an unmasked person at 3 metres gets a lesser load than a masked person using an N95 mask at 1 metre.
If one is very close to a person and mouths and faces at roughly the same height, the load will be higher,as the aerosol has yet to disperse. This has implications for say a cyclist directly following another cyclist maybe 5 metres apart , in their slipstream . ,But only half a second behind. For viral load calculations ,they are extremely close..maybe 1/2 metre
The reason nurses and care assistants are more infected is because they need to be within 1 metre, and are there for extended periods perhaps 8 hrs on the trot. And probability means that intensity x duration ... So they need the masks ,but these delay not prevent.
There is unfortunately evidence that the current ventilators etc can actually create airborne transmission.. in the space around the ward.
And yes there are plenty of tests carried out on non traditional masks and their efficacy. The old vacuum cleaner paper bags are really good at 99% unfortunately breathing through them is difficult. A simple cotton tee shirt is a good compromise. About 50% capture and not unpleasant to breath through.
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The 0.5 x 0.5 is the risk of being infected by both of them. The risk of being infected by at least one of them is 0.5+0.5 - 0.5*0.5 = 0.75.
That is 0.5 (risk of being infected by A) + 0.5 (risk of being infected by B) - 0.5*0.5 (risk of being infected by both).
You must remember the TCP advert song many years ago where one of the lines went. "take TCP and gargle every day, until the soreness goes away"
it's the viral load density.
You need to look at the diffusion across a membrane.
Fick's laws of diffusion - Wikipedia
en.wikipedia.org
Droplets will stay suspended for hours in still air and in closed spaces.
Their own accumulated droplets will leak out more as the masks get dirty. The efficacy of the mask will reduce in a closed space and the mask eventually lets out as nearly as much as if it weren't there.
I always stay as little as possible inside any closed space, mask or not.
I am not sure about this. I am not disputing your math, I think that is correct. I think Taleb was talking about reducing the amount of virus being released into the air and not the risk of being infected. The 50% figure is not the likelihood of someone catching the virus, it is instead the amount by which the virus is held back in the mask and hence not released into the air.
That sounds like the policy of my ancestors
Masks, dislike of being locked up..
It's a Border Riever thing
Incredible view from
@WISN12News
News Chopper 12 over Madison this afternoon showing the “stay home” protest against
@GovEvers
order. That is a lot of people. Our crew on the ground reports some people are carrying long guns at this protest.
And a pertinent reaction!
There is not now, and will never be, a vaccine against Human Stupidity
@WISN12News
News Chopper 12 over Madison this afternoon showing the “stay home” protest against
@GovEvers
order. That is a lot of people. Our crew on the ground reports some people are carrying long guns at this protest.
And a pertinent reaction!
There is not now, and will never be, a vaccine against Human Stupidity
Simpler way to put it (especially with lots of people), what is the chance of not being infected by any.
The chance of not being infected by 1 is 1-0.5 = 0.5;
The chance of not being infected by any of 6 is (1-0.5)^6 = 0.5 x 0.5 x 0.5 x 0.5 x 0.5 x 0.5 = 0.015625
so chance of being infected by at least 1 of 6 is 1- 0.015625 = 0.984375
It's not really as bad as it says, because actually the chance of being infected even within 0.5 metre of somebody infected is pretty small, as long as the closeness time is only a few seconds.
As many others have said, social distancing is probably more effective than masks.