If I have uniformed prior 1 to 1 on natural vs lableak origin, and update on 5 per cent coincidence that origin place is near lab, I will get around 95 per cent for lableak.
What is the relevance of the “posterior” that you get after updating on a single claim that’s being chosen, post-hoc, as the one that you want to use as an example?
Using a weak prior biases towards thinking the information you have to update with is strong evidence. How did you decide on that particular prior? You should presumably have some reference class for your prior. (If you can’t do that, you should at least have equipoise between all reasonable hypotheses being considered. Instead, you’re updating “Yes Lableak” versus “No Lableak”—but in fact, “from a Bayesian perspective, you need an amount of evidence roughly equivalent to the complexity of the hypothesis just to locate the hypothesis in theory-space. It’s not a question of justifying anything to anyone.”)
How confident are you in your estimate of the bayes factor here? Do you have calibration data for roughly similar estimates you have made? Should you be adjusting for less than perfect confidence?
To start, the claim that it was found 2 miles from the facility is an important mistake, because WIV is 8 miles from the market. For comparison to another city people might know better, in New York, that’s the distance between World Trade Center and either Columbia University, or Newark Airport. Wuhan’s downtown is around 16 miles across. 8 miles away just means it was in the same city.
And you’re over-reliant on the evidence you want to pay attention to. For example, even rstricting ourselves to “nearby coincidence” evidence, the Hunan the market is the largest in central China—so what are the odds that a natural spillover events occurs immediately surrounding the largest animal market? If the disease actually emerged from WIV, what are the odds that the cases centered around the Hunan market, 8 miles away, instead of the Baishazhou live animal market, 3 miles away, or the Dijiao market, also 8 miles away?
So I agree that an update can be that strong, but this one simply isn’t.
Yes, my mistake for the distance. Confused it with local CDC, which is like 600 meters from the market.
The place where most human cases are concentrated is the place where human-to-human transmission started—or there was multiple events of animal-to-human transmission in this place. The second thing would be surprising as if the virus can so often jump to humans from animals it will happen closer to its origin in Laos.
Alternative explanation is following: as the market is one of the most crowded place in the city (not sure, heard about it somewhere) it worked as an amplification of a single transmission event which could happen elsewhere.
If we assume that a worker of WIH was infected at work, this will be completely unspectacular until he started infecting other people. Such person can commute all around the city including to CDC near wet market.
My point: 8 miles or 2 miles is not big difference here, as the virus came to market not by air but with a commuting person, and 8 miles day commute is pretty normal. The market being big is not also a strong evidence as the animal number in smaller markets all over china will overweight animal-number in one big market.
The second thing would be surprising as if the virus can so often jump to humans from animals it will happen closer to its origin in Laos.
Spillover events probably did happen elsewhere, but not all spillover events lead to a pandemic, and covid is usually so mild that it’s not surprising we can’t find any such cases. (I also don’t know if some final important mutation didn’t happen until much closer to the actual pandemic start).
Alternative explanation is following: as the market is one of the most crowded place in the city
This is discussed in the Rootclaim debate. There are many different types of places which served as superspreader events early on, the evidence we have shows the growth rate in the market as the same outside of it, and overall growth didn’t seem to slow down when they closed the market.
If we assume that a worker of WIH was infected at work, this will be completely unspectacular until he started infecting other people. Such person can commute all around the city including to CDC near wet market.
This is also addressed. It would be a fantastic coincidence—much stronger than the one you posited at the start of this thread—if the only place they brought the disease was one of only a handful of other places in the city that a pandemic could actually start. Like, if all the early cases clustered around the WIV, and I said that a HSM worker could have brought it to the lab, would anyone take that seriously?
This, by the way, is exactly the kind of thing that annoys me and which is one of the main issues I made this thread to address. If you make enough favorable assumptions, you can make any hypothesis look good. This is clearly not the best explanation for the available evidence. Merely because you have successfully epicycled your way into a version of the theory which is not obviously impossible doesn’t mean anyone has any reason to think it is even remotely likely. Your arguments aren’t even consistent, as you seem surprised that there were no spillovers between Wuhan and Laos, but then don’t seem at all skeptical of the idea that a sick person would commute all over the city and only bring it to 1 place.
I mean, I could point out that the first non-Wuhan case was in Beijing on December 17th (I think, going off memory here) and that someone could have gotten sick in a different city, and then just hopped on a train and immediately went to the HSM, and the WIV isn’t relevant at all. Is this story convincing? Is there any evidence to support it? Does it feel like I am engaging in truth-seeking, or just throwing shit at a wall and seeing what sticks so I can prop up my pet theory?
ICUs were overwhelmed because Covid spread so much. Its hospitalization rate is a few percent and its fatality rate is 1% or so. This is in contrast to diseases like SARS 1 (9.5% fatality rate) or MERS (34% fatality rate). Sure, it’s not mild compared to seasonal flu, but it is much more mild than the obvious things you would compare it to.
Thank for explaining your position which is interesting and consistent.
I can suggest that the connection between WIH and wet market can be explained by the idea that some criminals sold lab animals from WIH on the wet market, e.g. bats.
Obviously this looks like ad hoc theory. But the travel of the virus to the market from the Laos caves also seems to be tricky and may include some steps like intermediate carrier. Both look equally unlikely, one of the happened.
So my idea is to ignore all the details and small theories; instead just updated on the distances to two possible origins points: 8 miles and 900 miles. This is 100 times difference and if we count the areas—it is 10000 times difference. In last case we can make so powerful update in the direction of WIH as source, that it overrides all other evidence.
What facility? WIV and HSM are at least 6 miles apart as the crow flies, with a big river between that forces anyone traveling from one to the other to go even further than that.
To override this we need some mental equlibristics (I think of meme here but I don’t want to be rude)
No, you just need stronger evidence. 1⁄20 isn’t that strong, especially for a complex situation with a high number of possible parameters to check.
If I have uniformed prior 1 to 1 on natural vs lableak origin, and update on 5 per cent coincidence that origin place is near lab, I will get around 95 per cent for lableak.
What is the relevance of the “posterior” that you get after updating on a single claim that’s being chosen, post-hoc, as the one that you want to use as an example?
Using a weak prior biases towards thinking the information you have to update with is strong evidence. How did you decide on that particular prior? You should presumably have some reference class for your prior. (If you can’t do that, you should at least have equipoise between all reasonable hypotheses being considered. Instead, you’re updating “Yes Lableak” versus “No Lableak”—but in fact, “from a Bayesian perspective, you need an amount of evidence roughly equivalent to the complexity of the hypothesis just to locate the hypothesis in theory-space. It’s not a question of justifying anything to anyone.”)
How confident are you in your estimate of the bayes factor here? Do you have calibration data for roughly similar estimates you have made? Should you be adjusting for less than perfect confidence?
My point was that in some cases the update can be so strong that it overrides all reasonable uncertainties in priors and personal estimates.
And exactly this makes Bayes’ theorem useful and strong instrument.
The fact that the virus was found in 2 miles from the facility which was supposed to research them—must make our bells ring.
To override this we need some mental equlibristics (I think of meme here but I don’t want to be rude)
To start, the claim that it was found 2 miles from the facility is an important mistake, because WIV is 8 miles from the market. For comparison to another city people might know better, in New York, that’s the distance between World Trade Center and either Columbia University, or Newark Airport. Wuhan’s downtown is around 16 miles across. 8 miles away just means it was in the same city.
And you’re over-reliant on the evidence you want to pay attention to. For example, even rstricting ourselves to “nearby coincidence” evidence, the Hunan the market is the largest in central China—so what are the odds that a natural spillover events occurs immediately surrounding the largest animal market? If the disease actually emerged from WIV, what are the odds that the cases centered around the Hunan market, 8 miles away, instead of the Baishazhou live animal market, 3 miles away, or the Dijiao market, also 8 miles away?
So I agree that an update can be that strong, but this one simply isn’t.
Yes, my mistake for the distance. Confused it with local CDC, which is like 600 meters from the market.
The place where most human cases are concentrated is the place where human-to-human transmission started—or there was multiple events of animal-to-human transmission in this place. The second thing would be surprising as if the virus can so often jump to humans from animals it will happen closer to its origin in Laos.
Alternative explanation is following: as the market is one of the most crowded place in the city (not sure, heard about it somewhere) it worked as an amplification of a single transmission event which could happen elsewhere.
If we assume that a worker of WIH was infected at work, this will be completely unspectacular until he started infecting other people. Such person can commute all around the city including to CDC near wet market.
My point: 8 miles or 2 miles is not big difference here, as the virus came to market not by air but with a commuting person, and 8 miles day commute is pretty normal. The market being big is not also a strong evidence as the animal number in smaller markets all over china will overweight animal-number in one big market.
Spillover events probably did happen elsewhere, but not all spillover events lead to a pandemic, and covid is usually so mild that it’s not surprising we can’t find any such cases. (I also don’t know if some final important mutation didn’t happen until much closer to the actual pandemic start).
This is discussed in the Rootclaim debate. There are many different types of places which served as superspreader events early on, the evidence we have shows the growth rate in the market as the same outside of it, and overall growth didn’t seem to slow down when they closed the market.
This is also addressed. It would be a fantastic coincidence—much stronger than the one you posited at the start of this thread—if the only place they brought the disease was one of only a handful of other places in the city that a pandemic could actually start. Like, if all the early cases clustered around the WIV, and I said that a HSM worker could have brought it to the lab, would anyone take that seriously?
This, by the way, is exactly the kind of thing that annoys me and which is one of the main issues I made this thread to address. If you make enough favorable assumptions, you can make any hypothesis look good. This is clearly not the best explanation for the available evidence. Merely because you have successfully epicycled your way into a version of the theory which is not obviously impossible doesn’t mean anyone has any reason to think it is even remotely likely. Your arguments aren’t even consistent, as you seem surprised that there were no spillovers between Wuhan and Laos, but then don’t seem at all skeptical of the idea that a sick person would commute all over the city and only bring it to 1 place.
I mean, I could point out that the first non-Wuhan case was in Beijing on December 17th (I think, going off memory here) and that someone could have gotten sick in a different city, and then just hopped on a train and immediately went to the HSM, and the WIV isn’t relevant at all. Is this story convincing? Is there any evidence to support it? Does it feel like I am engaging in truth-seeking, or just throwing shit at a wall and seeing what sticks so I can prop up my pet theory?
It is mild now. It was not mild in the early stages. ICUs in many places were overwhelmed.
ICUs were overwhelmed because Covid spread so much. Its hospitalization rate is a few percent and its fatality rate is 1% or so. This is in contrast to diseases like SARS 1 (9.5% fatality rate) or MERS (34% fatality rate). Sure, it’s not mild compared to seasonal flu, but it is much more mild than the obvious things you would compare it to.
Thank for explaining your position which is interesting and consistent.
I can suggest that the connection between WIH and wet market can be explained by the idea that some criminals sold lab animals from WIH on the wet market, e.g. bats.
Obviously this looks like ad hoc theory. But the travel of the virus to the market from the Laos caves also seems to be tricky and may include some steps like intermediate carrier. Both look equally unlikely, one of the happened.
So my idea is to ignore all the details and small theories; instead just updated on the distances to two possible origins points: 8 miles and 900 miles. This is 100 times difference and if we count the areas—it is 10000 times difference. In last case we can make so powerful update in the direction of WIH as source, that it overrides all other evidence.
They’re not equally unlikely. You haven’t provided any actual evidence for this claim.
Also, why on Earth would we just take the ratio of distances or areas as the probability factor? That’s not how pandemics work.
What facility? WIV and HSM are at least 6 miles apart as the crow flies, with a big river between that forces anyone traveling from one to the other to go even further than that.
No, you just need stronger evidence. 1⁄20 isn’t that strong, especially for a complex situation with a high number of possible parameters to check.