Update: Most information presented here is out of date. See the 80,000 hours page for more up-to-date information.

I have been researching the Wuhan Coronavirus for several hours today, and I have come to the tentative conclusion that the situation is worse than I initially thought.

Given my current understanding, it now seems reasonable to assign a non-negligible probability (>2%) to the proposition that the current outbreak will result in a global disaster (>50 million deaths resulting from the pathogen within 1 year). I understand this prediction will sound alarmist, but in this post I will outline some of the reasons why I have come to this conclusion.

I now believe that it is warranted for effective altruists to take particular actions to prepare for a resulting pandemic. The most effective action is likely to research preparation in order to limit exposure to sources of the virus. Sending out evidence-based warning signals to at-risk communities may also be effective at limiting the spread of the pathogen.

Summary of my reasons for believing that this outbreak could result in a global disaster

  • The current outbreak matches the criteria that scientists have identified as being particularly likely characteristics of a pandemic-induced global disaster. That is, it’s a disease that’s contagious during a long incubation period, has a high infection rate, has no known treatment, few people are immune, and it has a low but significant mortality rate. See this article for a summary of likely characteristics of a pandemic-induced global disaster.
    • Based on my research, I wasn't able to identify any historically recent pathogen with these characteristics, giving me reason to believe that using an outside view to argue against alarmism may not be warranted. For reference, the 2003 SARS outbreak, the 2009 Swine Flu, and the several Ebola outbreaks do not match the profiles of a global disaster as completely as the current outbreak.
    • Estimates of the mortality rate vary, but one media source says, "While the single figures of deaths in early January seemed reassuring, the death toll has now climbed to above 3 percent." This would put it roughly on par with the mortality rate of the 1918 flu pandemic, and over 10 times more deadly than a normal seasonal flu. It’s worth noting, however, that the 1918 flu pandemic killed mostly young adults, whereas the pattern for this pathogen appears to be the opposite (which is normal for pathogens).
    • The incubation period (the period during which symptoms are not present but those infected can still infect others) could be as long as 14 days, according to many sources.
  • An Imperial College London report stated, "Self-sustaining human-to-human transmission of the novel coronavirus (2019-nCov) is the only plausible explanation of the scale of the outbreak in Wuhan. We estimate that, on average, each case infected 2.6 (uncertainty range: 1.5-3.5) other people up to 18th January 2020, based on an analysis combining our past estimates of the size of the outbreak in Wuhan with computational modelling of potential epidemic trajectories. This implies that control measures need to block well over 60% of transmission to be effective in controlling the outbreak."
    • Compare the above infection rate to the H1N1 virus, which some estimate to have infected 10-20% of the world population in 2009. The World Health Organization has said, "The pandemic (H1N1) 2009 influenza virus has a R0 of 1.2 to 1.6 (Fraser, 2009) which makes controlling its spread easier than viruses with higher transmissibility."
  • A simple regression model indicates that the growth rate of the pathogen is predictable and extremely rapid.
    • The number of cases as reported by the National Health Commission of China forms the basis of my regression model (you can currently find the number of cases reported in graphical format on the Wikipedia page here). An exponential regression model fit to the data reveals that the equation 38.7 * e^(0.389 * (t+11)) strongly retrodicts the number of cases (where t is the number of days since January 26th). In this model, the growth is very high.
    • [Update: Growth for January 27th remained roughly in line with the predicted growth from the exponential regression model. The new equation is 35.5*exp(0.401*t) where t is the number of days since January 15th]
  • A top expert has estimated that approximately 100,000 people have already been infected, which is much more than the confirmed number of 2808 (as of January 26th). If the number were this high, then the pathogen has likely already crossed the quarantine. The infection has also spread to 12 other countries besides China, supporting this point.
  • The Metaculus community’s estimate for the number of total cases in 2020 is much higher than it was just two or three days ago. Compare this older question here, versus this new question (when it opens).
  • While several organizations are developing a vaccine, Wikipedia seems to indicate that it will take months before vaccines even enter trials, and we should expect that it will take about a year before a vaccine comes out.

Summary of my recommendations

I think it's unlikely that EAs are in any special position to help stop the pandemic. However, we can guard ourselves against the pandemic by heeding early warnings, research ways to limit our exposure to the virus, and use our platforms to warn those at-risk.

The CDC has a page for preparing for disaster.

Currently, the pathogen appears to have a significant mortality rate, but kills mainly older people. Therefore, old people are most at-risk of dying.

Even if you contract the disease and don't die, the symptoms are likely to be severe. One source says,

ARDS (acute respiratory distress syndrome) is a common complication. Between 25 and 32 percent of cases are admitted to the intensive care unit (ICU) for mechanical ventilation and sometimes ECMO (pumping blood through an artificial lung for oxygenation).
Other complications include septic shock, acute kidney injury, and virus-induced cardiac injury. The extensive lung damage also sets the lung up for secondary bacterial pneumonia, which occurs in 10 percent of ICU admissions.

Acknowledgements: Dony Christie and Louis Francini helped gather sources and write this post.


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This straightforwardly got the novel coronavirus (now "covid-19") on the radar of many EAs who were otherwise only vaguely aware of it, or thought it was another media panic, like bird flu. 

The post also illustrates some of the key strengths and interests of effective altruism, like quantification, forecasting, and ability to separate out minor global events from bigger ones.

In addition, I'll mention: * Foretold is tracking ~20 questions [https://www.foretold.io/c/c47c6bc8-2c9b-4a83-9583-d1ed80a40fa2]and is open to anyone adding their own, but doesn't have very many predictions. * In addition to the one you mentioned, Metaculus is tracking a handful of other questions [https://www.metaculus.com/questions/?order_by=-activity&search=coronavirus] and has a substantial number of predictions. * The John Hopkins disease prediction project [http://www.centerforhealthsecurity.org/our-work/disease-prediction]lists 3 questions. You have to sign up to view them. (I also think you can't see the crowd average before you've made your prediction.)
1Nathan Young3y
Hey, I suggest the question you've linked has an artificially low upper bound. Please could you update the link with this Metaculus question which, without the upper bound, provides a better prediction. All metaculus questions are about cases, not deaths. Currently the most up to date community prediction is a 7% chance of over a billion cases this year. I am not sure where you found the claim you cite. Apologies if I've made some mistake. https://www.metaculus.com/questions/3529/how-many-human-infections-of-the-2019-novel-coronavirus-2019-ncov-will-be-estimated-to-have-occurred-before-2021-question-two/ [https://www.metaculus.com/questions/3529/how-many-human-infections-of-the-2019-novel-coronavirus-2019-ncov-will-be-estimated-to-have-occurred-before-2021-question-two/]
The question has an upper bound of 100 million deaths, not cases. I don't think that is "artificially low". Maybe you are confusing Hurford's link with this old question [https://www.metaculus.com/questions/3505/how-many-human-infections-of-the-2019-novel-coronavirus-2019-ncov-will-be-estimated-to-occur-before-2021-question-one/] , which does have an artificially low upper bound and deals with cases instead of deaths. Most of them are, but the one Hurford linked to is explicitly about the number of deaths: "How many people will die as a result of the 2019 novel coronavirus (2019-nCoV) before 2021?". If you look at the bottom of the page, it says that the community predicts a ~3% chance of greater than 100 million deaths. Previously, it said 2% for the same number of deaths. Just to be absolutely clear about what I am referring to, here is a screenshot [https://i.imgur.com/fjh4hG8.png] of the relevant part of the UI.
1Nathan Young3y
You are entirely correct. My bad.
[Comment not relevant]

For a long time, I've believed in the importance of not being alarmist. My immediate reaction to almost anybody who warns me of impending doom is: "I doubt it". And sometimes, "Do you want to bet?"

So, writing this post was a very difficult thing for me to do. On an object-level, l realized that the evidence coming out of Wuhan looked very concerning. The more I looked into it, the more I thought, "This really seems like something someone should be ringing the alarm bells about." But for a while, very few people were predicting anything big on respectable forums (Travis Fisher, on Metaculus, being an exception), so I stayed silent.

At some point, the evidence became overwhelming. It seemed very clear that this virus wasn't going to be contained, and it was going to go global. I credit Dony Christie and Louis Francini with interrupting me from my dogmatic slumber. They were able to convince me —in the vein of Eliezer Yudkowsky's Inadequate Equilibria —that the reason why no one was talking about this probably had nothing to do whatsoever  with the actual evidence. It wasn't that people had a model and used that model to predict "no doom" with high confidence: it was a case of peo... (read more)

This is the boring take, but it's worth noting that conditional on this spreading widely, perhaps the most important things to do are mitigating health impacts on you, not preventing transmission. And that means staying healthy in general, perhaps especially regarding cardiovascular health - a good investment regardless of the disease, but worth re-highlighting.

I'm not a doctor, but I do work in public health. Based on my understanding of the issues involved, if you want to take actions now to minimize severity later if infected, my recommendations are:

  • Exercise (which will help with cardiovascular health)
  • Lose excess weight (which can exacerbate breathing issues)
  • Get enough sleep (which assists your immune system generally)
  • Eat healthy (again, general immune system benefits)

And for preventing transmission, I know it seems obvious, but you need to actually wash your hands. Also, it seems weird, by studies indicate that brushing teeth seems to help reduce infection rates.

And covering your mouth with a breathing mask may be helpful, as long as you're not, say, touching food with your hands that haven't been washed recently and then eating. Also, even if there is no Coronavirus, in general, wash your hands before eating. Very few people are good about doing this, but it will help.

Nice list! Adding to it a little: * Avoid being sick with two things at once or being sick with something else immediately before. * When it comes to supplements the evidence and effect sizes are not that strong. Referencing examine.com [https://examine.com/] and what I generally remember, I roughly think that the best immune system strengthening supplements would be zinc and echinacea with maybe mild effects from other things like vitamin C, vitamin D, and whey protein. There may be a couple additional herbs that could do something but it's unclear they are safe to take for a long duration. What you'd aim for is decreasing the severity of viral pnemonia induced by something like influenza. * It's possible that some existing antivirals will be helpful but currently this is unknown.
Re exercise: I worry that putting myself in a catabolic state (by exercising particularly hard) I temporarily increase my risk. Also by being at the gym around sweaty strangers. Is this worry justified?
I don't think so to any significant extent in most circumstances. And any tiny spike counterbalanced by general benefits pointed to by David. My understanding (former competitive runner) is that extended periods of heavily overdoing it with exercise (overtraining) can lead to an inhibited immune system among other symptoms, but this is rare with people generally keeping fit (other than e.g. someone jumping into marathon/triathlon training without building up). Other things to avoid/be mindful of are the usual (hanging around in damp clothes in the cold, hygiene in group sporting/exercise contexts etc).
4Will Bradshaw3y
I feel much more worried about being in a crowded gym than about immune effects of exercise. People are really bad at (a) cleaning gym equipment and (b) washing their hands. To be clear, I'd guess this is less bad than many other social situation (bars, public transport, restaurants) as well as carrying a much clearer health upside. But perhaps there is an argument for switching to more solitary forms of exercise in outbreak situations? And obviously you should not go to the gym if you yourself are sick (people apparently do this)!

Thanks for this. I found this article on how to personally prevent its spread helpful: https://foreignpolicy.com/2020/01/25/wuhan-coronavirus-safety-china/

[This comment is no longer endorsed by its author]Reply
For people living in the US, at what point does it become particularly important to start following these methods? I assume it’s always beneficial, but risk adjusted not particularly important until there start being more cases in the US or until we start having more cases. Is that assumption right or dangerously wrong?
4Juan Cambeiro3y
There doesn't seem to be any local transmission in the US yet - so for now, I guess it probably wouldn't help much (though it would still help prevent the spread of the common cold/flu!). If/when there is local transmission, following this advice will be very important.
The CDC and WHO emphasise handwashing, not gloves. "WHO experts advise against wearing gloves on the basis that hand-washing is more important and people wearing gloves are less likely to wash their hands." https://www.theguardian.com/science/2020/jan/27/coronavirus-how-to-protect-yourself-from-infection [https://www.theguardian.com/science/2020/jan/27/coronavirus-how-to-protect-yourself-from-infection]
Alcohol-based hand sanitiser is also good. Often better than hand washing in practice as very few people actually wait for the water to get warm, or spend 20 seconds lathering the soap.
While I agree that most people don't wash their hands correctly, I was recently surprised to learn that warm water doesn't make much of a difference when it comes to killing germs. https://medicalsciences.stackexchange.com/questions/500/does-hot-water-kill-germs-better-than-cold-water [https://medicalsciences.stackexchange.com/questions/500/does-hot-water-kill-germs-better-than-cold-water]
Makes sense from the point of view of killing germs, and temperatures being tolerable for us also being tolerable for germs. My intuition is that it's easier to get dirt (which contains germs) off hands with warmer water (similar to how it's easier to wash dishes with warmer water).

I'm willing to bet up to $100 at even odds that by the end of 2020, the confirmed death toll by the Wuhan Coronavirus (2019-nCoV) will not be over 10,000. Is anyone willing to take the bet?

I accepted a bet on January 30th with a friend with the above terms. Nobody else offered to bet me. Since then, I have updated my view. I now give a ~60% probability that there will be over 10,000 deaths. https://predictionbook.com/predictions/198256 [https://predictionbook.com/predictions/198256] My update is mostly based on (a) Metaculus's estimate of the median number of deaths updating from ~3.5k to now slightly over ~10K ( https://www.metaculus.com/questions/3530/how-many-people-will-die-as-a-result-of-the-2019-novel-coronavirus-2019-ncov-before-2021/ [https://www.metaculus.com/questions/3530/how-many-people-will-die-as-a-result-of-the-2019-novel-coronavirus-2019-ncov-before-2021/] ) and also (b) some naive extrapolation of the possible total number of deaths based on the Feb 4th death data here: https://www.worldometers.info/coronavirus/coronavirus-death-toll/ [https://www.worldometers.info/coronavirus/coronavirus-death-toll/]

Incubation period and Chinese government coverup efforts are relevant to this question, but roughly speaking if the actual number of infections is ~35x the reported number, and there's no uptick in mysterious deaths in hospitals, then the actual mortality rate is ~1/35 the reported number, more in line with normal flu than 1918 Spanish flu.

Current death rates are likely to underestimate the total mortality rate, since the disease has likely not begun to affect most of the people who are infected.

I'll add information about incubation period to the post.

By total mortality rate do you mean total number of people eventually or do you mean percentage? If the former I agree. If you mean the later... I see it as a toss up between the selection effect of the more severely affected being the ones we know have it (and so decreasing the true mortality rate relative to the published numbers) and time for the disease to fully progress (and so increasing the true mortality rate relative to the published numbers).
Estimates of the mortality rate vary, but one media source says, "While the single figures of deaths in early January seemed reassuring, the death toll has now climbed to above 3 percent." This would put it roughly on par with the mortality rate of the 1918 flu pandemic.

It should be noted that the oft-cited case-fatality ratio of 2.5% for the 1918 flu might be inaccurate, and the true CFR could be closer to 10%: https://rybicki.blog/2018/04/11/1918-influenza-pandemic-case-fatality-rate/?fbclid=IwAR3SYYuiERormJxeFZ5Mx2X_00QRP9xkdBktfmzJmc8KR-iqpbK8tGlNqtQ

EDIT: Also see this twitter thread: https://twitter.com/ferrisjabr/status/1232052631826100224

Howie and I just recorded a 1h15m conversation going through what we do and don't know about nCoV for the 80,000 Hours Podcast.

We've also compiled a bunch of links to the best resources on the topic that we're aware of which you can get on this page.


I find the analysis from this link very interesting. It suggests that Ro is higher than initially estimated at 3-4 (rather than 1.4-2.5 by WHO) but the national China mortality rate drops to 0.3% if the province of Hubei is excluded (the reported mortality rate of Wuhan alone is 5.5%). This would be consistent with the theory that the number of cases are underreported in Wuhan, due to a shortage of testing capacity and perhaps under reporting. A recent Lancet report by Professor Gabriel Leung from University of Hong Kong https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(20)30260-9/fulltext estimates 76,000 cases in Wuhan as of Jan 25th based on a Ro of 2.68, more than 30x reported, which would put the mortality rate at well under 0.5%.

This suggests the pandemic could be more difficult to control than expected but mortality rate is also much lower (perhaps in the region of 3x flu).

This may also mean the main damage could be through economic impact.

I am extremely skeptical of the high R0 estimate for one reason: SARS has a lower R0, but was much worse overseas than nCov currently is. According to the Lancet report you linked, SARS has an R0 of around 2 in China, so substantially lower than nCov. However, we know how the first cases abroad spread. Compared to the current situation, it was far far worse, by mortality and by number of cases. The first case in Toronto infected first her family, then some hospital works who in turn spread it further until the whole hospital had to be closed. Eyeballing the graph for Canada found here, this really does not look like the situation we currently have, despite higher interconnection and more rigorous testing (more testing -> more discovered cases). So far the majority of overseas cases are still travelers from China; the people that they infected are generally close contacts; it is positively surprising how few spouses seem to get the virus. This can also not just be attributed to higher awareness I think. Even before the news story of a new dangerous story broke, there were no human-to-human transmissions overseas despite some travelers already present.
For posterity, I was wrong here because I was unaware of the dispersion parameter k that is substantially higher for SARS than for Covid-19.
Great thanks for this and the link. I am still trying to understand this more as it evolves. I guess as the monitoring and control is now much stronger hopefully Ro will come down also.
The link to the Lancet study seems to be broken when I click on it, although the text of the link itself is correct. This should be (hopefully) a working link: https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(20)30260-9/fulltext [https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(20)30260-9/fulltext]

I am an EA living in China right now. Thanks for sharing this post on the Coronavirus. I am also very interested in these questions.

We do not know what percentage of people experience symptoms so mild that they do not seek medical attention and so do not appear in the 'Suspected' or 'Confirmed' case statistics.

here: https://ncov.dxy.cn/ncovh5/view/pneumonia

and here: https://www.worldometers.info/coronavirus/

Here’s Google Translate if you need it: https://translate.google.com/

Nevertheless, as you mentioned, attempts have been made to model the spread of the infection and to estimate the number of people carrying the virus so far.

I have created a very simple spreadsheet with three scenarios here:


The Red scenario = 50% of infections go undiagnosed (unrecorded).

The Yellow scenario = 70% of infections go undiagnosed (unrecorded).

The Green scenario = 85% of infections go undiagnosed (unrecorded).

Each scenario has different estimates of the ‘real’ number of infections and percentages that progress to either a serious/critical condition or to de... (read more)

Just some quick thoughts: -Your lowest discovery rate (15%) might still be too high, this recent preprint estimates 0.05% https://www.medrxiv.org/content/10.1101/2020.01.23.20018549v2.full.pdf [https://www.medrxiv.org/content/10.1101/2020.01.23.20018549v2.full.pdf] -The spreadsheet compares the current number of deaths with the current number of known cases. However, deaths will always leak behind the number of confirmed cases; this way you will be underestimating death rate. -It might also be interesting to do some back of the envelope math on the cases outside of China, since discovery rate should be much higher. So far, there are very few serious, and I think no critical conditions. However, most confirmed infections outside of China are actually people who were infected in China and then traveled overseas which selects for people healthy enough to travel, so mostly younger. Doing a proper analysis of those numbers will be hard; one could compare them to SARS figures of the relevant age bracket.
Sorry, the link to the 'live' statistics from Chinese Health centres was broken: https://ncov.dxy.cn/ncovh5/view/pneumonia [https://ncov.dxy.cn/ncovh5/view/pneumonia] I've also updated the link in the original post. Here’s Google Translate if you need it: https://translate.google.com/ [https://translate.google.com/]

Thanks for the article. One thing I'm wondering about that has implications for the large scale pandemic case is how much equipment for "mechanical ventilation and sometimes ECMO (pumping blood through an artificial lung for oxygenation)" does society have and what are the consequences of not having access to such equipment? Would such people die? In that case the fatality rate would grow massively to something like 25 to 32%.

Whether there is enough equipment would depend upon how many get sick at once, can more than one person use the same equipment in an interleaved fashion, how long each sick person needs the equipment, are their good alternatives to the equipment, and how quickly additional equipment could be built or improvised.

So the case I'd be worried about here would be a very quick spread where you need rare expensive equipment to keep the fatality rate down where it is currently.

A study published today attempts to estimate the nCoV incubation period:

Using the travel history and symptom onset of 34 confirmed cases that were detected outside Wuhan, we estimate the mean incubation period to be 5.8 (4.6 – 7.9, 95% CI) days, ranging from 1.3 to 11.3 days (2.5th to 97.5th percentile).

As the authors note, this estimate indicates an incubation period remarkably similar to that of the Middle East respiratory syndrome.

It's now been more than two weeks since infected people have been diagnosed in countries like Thailand, but there's no outbreak in Thailand. There have so far been 14 cases in Thailand, all brought directly from China rather than from person-to-person infection in Thailand.

That makes me feel more skeptical that this will become a worldwide pandemic.

FYI - study of outcomes a/o Jan 25 for all 99 2019-nCoV patients admitted to a hospital in Wuhan between Jan 1 and Jan 20.

Many caveats apply. Only includes confirmed cases, not suspected ones. People who end up at a hospital are selected for being more severely ill. 60% of the patients have not yet been discharged so haven't experienced the full progression of the disease. Etc.


I wonder what sort of Fermi calculation we should apply to this? My quick (quite possibly wrong) numbers are:

  • P(it goes world scale pandemic) = 1/3, if I believe the exponential spreading math (hard to get my human intuition behind) and the long, symptom less, contagious incubation period
  • P(a particular person gets it | it goes world scale pandemic) = 1/3, estimating from similar events
  • P(a particular person dies from it | a particular person gets it) = 1/30, and this may be age or preexisting condition agnostic and could, speculatively, increase if vital equipment is too scarce (see other comment)

=> P(death of a randomly selected person from it) = ~1/300

What are your thoughts?

Updating the Fermi calculation somewhat:

  • P(it goes world scale pandemic) = 1/3, no updates (the metaculus estimate reference in another comment counteracted my better first principles estimation)
  • P(a particular person gets it | it goes world scale pandemic) = 1/2, updating based on the reproduction number of the virus
  • P(a particular person dies from it | a particular person gets it) = 0.09, updating based on a guess of 1/2 probability rare equipment is needed and a random guess of 1/2 probability fatality without it. 1/2*1/30 + 1/2*((Probability of pneumonia: (1/3+1/4 )*1/2)*(Probability of fatality given pnemonia and rare equipment is needed: 1/2)

=> P(death of a randomly selected person from it) = ~1/67

I'm not entirely sure what to think of the numbers; I cannot deny the logic but it's pretty grim and I hope I'm missing some critical details, my intuitions are wrong, or unknown unknowns make things more favorable.

Hopefully future updates and information resolves some of the uncertainties here and makes the numbers less grim. One large uncertainty is how the virus will evolve in time.

Hmm. interesting. This goes strongly against my intuitions. In case of interest I'd be happy to give you 5:1 odds that this Fermi estimate is at least an order of magnitude too severe (for a small stake of up to £500 on my end, £100 on yours). Resolved in your favour if 1 year from now the fatalities are >1/670 (or 11.6M based on current world population); in my favour if <1/670.

(Happy to discuss/modify/clarify terms of above.)

Edit: We have since amended the terms to 10:1 (50GBP of Justin's to 500GBP of mine).

Hmm... I will take you up on a bet at those odds and with those resolution criteria. Let's make it 50 GBP of mine vs 250 GBP of yours. Agreed?

I hope you win the bet!

(note: I generally think it is good for the group epistemic process for people to take bets on their beliefs but am not entirely certain about that.)

Agreed, thank you Justin. (I also hope I win the bet, and not for the money - while it is good to consider the possibility of the most severe plausible outcomes rigorously and soberly, it would be terrible if it came about in reality). Bet resolves 28 January 2021. (though if it's within an order of magnitude of the win criterion, and there is uncertainty re: fatalities, I'm happy to reserve final decision for 2 further years until rigorous analysis done - e.g. see swine flu epidemiology studies which updated fatalities upwards significantly several years after the outbreak).

To anyone else reading. I'm happy to provide up to a £250 GBP stake against up to £50 of yours, if you want to take the same side as Justin.

Strong kudos for betting. Your estimates seem quite off to me but I really admire you putting them to the test. I hope, for the sake of the world, that you are wrong.

Re: whose mortality estimates, I suggest we use metaculus's list here (WHO has highest ranking) as standard (with the caveat above). https://www.metaculus.com/questions/3530/how-many-people-will-die-as-a-result-of-the-2019-novel-coronavirus-2019-ncov-before-2021/ [https://www.metaculus.com/questions/3530/how-many-people-will-die-as-a-result-of-the-2019-novel-coronavirus-2019-ncov-before-2021/]

Though it's interesting to note Justin's fermi is not far off how one of Johns Hopkins' CHS scenarios played out (coronavirus, animal origin, 65m deaths worldwide).


Note: this was NOT a prediction (and had some key differences including higher mortality associated with their hypothetical virus, and significant international containment failure beyond that seen to date with nCov)


Hmm. You're betting based on whether the fatalities exceed the mean of Justin's implied prior, but the prior is really heavy-tailed, so it's not actually clear that your bet is positive EV for him. (e.g., "1:1 odds that you're off by an order of magnitude" would be a terrible bet for Justion because he has 2/3 credence that there will be no pandemic at all).

Justin's credence for P(a particular person gets it | it goes world scale pandemic) should also be heavy-tailed, since the spread of infections is a preferential attachment process. If (roughly, I think) the median of this distribution is 1/10 of the mean, then this bet is negative EV for Justin despite seeming generous.

In the future you could avoid this trickiness by writing a contract whose payoff is proportional to the number of deaths, rather than binary :)

This seems fair. I suggested the bet quite quickly. Without having time to work through the math of the bet, I suggested something that felt on the conservative side from the point of view of my beliefs. The more I think about it, (a) the more confident I am in my beliefs and (b) the more I feel it was not as generous as I originalyl thought*. I have a personal liking for binary bets rather than proportional payoffs. As a small concession in light of the points raised, I'd be happy to offer to modify the terms retroactively to make them more favourable to Justin, offering either of the following. (i) Doubling the odds against me to 10:1 odds (rather than 5:1) on the original claim (at least an order of magnitude lower than his fermi). So his £50 would get £500 of mine. OR (ii) 5:1 on at least 1.5 orders of magnitude (50x) lower than his fermi (rather than 10x). (My intuition is that (ii) is a better deal than (i) but I haven't worked it through) (*i.e. at time of bet - I think the likelihood of this being a severe global pandemic is now diminishing further in my mind)
Sure, I'll take the modification to option (i). Thanks Sean.
10:1 on the original (1 order of magnitude) it is.

I respect that you are putting money behind your estimates and get the idea behind it, but would recommend you to reconsider if you want to do this (publicly) in this context and maybe consider removing these comments. Not only because it looks quite bad from the outside, but also because I'm not sure it's appropriate on a forum about how to do good, especially if the virus should happen to kill a lot of people over the next year (also meaning that even more people would have lost someone to the virus). I personally found this quite morbid and I have a lot more context into EA culture than a random person reading this, e.g. I can guess that the primary motivation is not "making money" or "the feeling of winning and being right" - which would be quite inappropriate in this context -, but that might not be clear to others with less context.

(Maybe I'm also the only one having this reaction in which case it's probably not so problematic)

edit: I can understand if people just disagree with me because you think there's no harm done by such bets, but I'd be curious to hear from the people who down voted if in addition to that you think that comments like mine are harmful because of being bad for epistemic habits or something, so grateful to hear if someone thinks comments like these shouldn't be made!

I have downvoted this, here are my reasons:

Pretty straightforwardly, I think having correct beliefs about situations like this is exceptionally important, and maybe the central tenet this community is oriented around. Having a culture of betting on those beliefs is one of the primary ways in which we incentivize people to have accurate beliefs in situations like this.

I think doing so publicly is a major public good, and is helping many others think more sanely about this situation. I think the PR risk that comes with this is completely dwarfed by that consideration. I would be deeply saddened to see people avoid taking these bets publicly, since I benefit a lot from both seeing people's belief put the test this way, and I am confident many others are too.

Obviously, providing your personal perspective is fine, but I don't think I want to see more comments like this, and as such I downvoted it. I think a forum that had many comments like this would be a forum I would not want to participate in, and I expect it to directly discourage others from contributing in ways I think are really important and productive (for example, it seems to have caused Sean below to seriously con... (read more)

I emphatically object to this position (and agree with Chi's). As best as I can tell, Chi's comment is more accurate and better argued than this critique, and so the relative karma between the two dismays me.

I think it is fairly obvious that 'betting on how many people are going to die' looks ghoulish to commonsense morality. I think the articulation why this would be objectionable is only slightly less obvious: the party on the 'worse side' of the bet seems to be deliberately situating themselves to be rewarded as a consequence of the misery others suffer; there would also be suspicion about whether the person might try and contribute to the bad situation seeking a pay-off; and perhaps a sense one belittles the moral gravity of the situation by using it for prop betting.

Thus I'm confident if we ran some survey on confronting the 'person on the street' with the idea of people making this sort of bet, they would not think "wow, isn't it great they're willing to put their own money behind their convictions", but something much more adverse around "holding a sweepstake on how many die".

(I can't find an ... (read more)

both metacalus and the John's Hopkins platform prediction have relevant questions which are much active, and where people are offering more information.

I am confused. Both of these are environments in which people participate in something very similar to betting. In the first case they are competing pretty directly for internet points, and in the second they are competing for monetary prices.

Those two institutions strike me as great examples of the benefit of having a culture of betting like this, and also strike me as similarly likely to create offense in others.

We seem to agree on the value of those platforms, and both their public perception and their cultural effects seem highly analogous to the private betting case to me. You even explicitly say that you expect similar reactions to questions like the above being brought up on those platforms.

I agree with you that were there only the occasional one-off bet on the forum that was being critiqued here, the epistemic cost would be minor. But I am confident that a community that had a relationship to betting that was more analogous to how Chi's relationship to betting appears to be, we would have never actually built th... (read more)

9Gregory Lewis3y
I'm extremely confident a lot more opprobrium attaches to bets where the payoff is in money versus those where the payoff is in internet points etc. As you note, I agree certain forecasting questions (even without cash) provoke distaste: if those same questions were on a prediction market the reaction would be worse. (There's also likely an issue the money leading to a question of ones motivation - if epi types are trying to predict a death toll and not getting money for their efforts, it seems their efforts have a laudable purpose in mind, less so if they are riding money on it). This looks like a stretch to me. Chi can speak for themselves, but their remarks don't seem to entail a 'relationship to betting' writ large, but an uneasy relationship to morbid topics in particular. Thus the policy I take them to be recommending (which I also endorse) of refraining making 'morbid' or 'tasteless' bets (but feel free to prop bet to heart's desire on other topics) seems to have very minor epistemic costs, rather than threatening some transformation of epistemic culture which would mean people stop caring about predictions. For similar reasons, this also seems relatively costless in terms of other perceptions: refraining from 'morbid' topics for betting only excludes a small minority of questions one can bet upon, leaving plenty of opportunities to signal its virtuous characteristics re. taking ideas seriously whilst avoiding those which reflect poorly upon it.
refraining from 'morbid' topics for betting only excludes a small minority of questions one can bet upon

This is directly counter to my experience of substantive and important EA conversation. All the topics I'm interested in are essentially morbid topics when viewed in passing by a 'person on the street'. Here are examples of such questions:

  • How frequently will we have major pandemics that kill over N people?
  • How severe (in terms of death and major harm) will the worst pandemic in the next 10 years be?
  • How many lives are saved by donations to GiveWell recommended charities? If we pour 10-100 million dollars into them, will we see a corresponding decline in deaths from key diseases globally?
  • As AI gets more powerful, will we get warning shots across the bow that injure
    or kill <10,000 people with enough time for us to calibrate to the difficulty of the alignment problem, or will it be more sudden than that?

Like, sometimes I even just bet on ongoing death rates. Someone might say to me "The factory farming problem is very small of course" and I'll reply "I will take a bet with you, if you're so confident. You say what you think it is, ... (read more)

All of your examples seem much better than the index case I am arguing against. Commonsense morality attaches much less distaste to cases where those 'in peril' are not crisply identified (e.g. "how many will die in some pandemic in the future" is better than "how many will die in this particular outbreak", which is better than "will Alice, currently ill, live or die?"). It should also find bets on historical events are (essentially) fine, as whatever good or ill implicit in these has already occurred.

Of course, I agree they your examples would be construed as to some degree morbid. But my recommendation wasn't "refrain from betting in any question where we we can show the topic is to some degree morbid" (after all, betting on GDP of a given country could be construed this way, given its large downstream impacts on welfare). It was to refrain in those cases where it appears very distasteful and for which there's no sufficient justification. As it seems I'm not expressing this balancing consideration well, I'll belabour it.


Say, God forbid, one of my friend's children has a life-limiting disease. On its fac... (read more)

4Ben Pace3y
I'm tapping out of this discussion. I disagree with much of the above, but I cannot respond to it properly for now.

I can guess that the primary motivation is not "making money" or "the feeling of winning and being right" - which would be quite inappropriate in this context

I don't think these motivations would be inappropriate in this context. Those are fine motivations that we healthily leverage in large parts of the world to cause people to do good things, so of course we should leverage them here to allow us to do good things.

The whole economy relies on people being motivated to make money, and it has been a key ingredient to our ability to sustain the most prosperous period humanity has ever experienced (cf. more broadly the stock market). Of course I want people to have accurate beliefs by giving them the opportunity to make money. That is how you get them to have accurate beliefs!

At least from a common-sense morality perspective, this doesn't sit right with me. I do feel that it would be wrong for two people to get together to bet about some horrible tragedy -- "How many people will die in this genocide?" "Will troubled person X kill themselves this year?" etc. -- purely because they thought it'd be fun to win a bet and make some money off a friend. I definitely wouldn't feel comfort

... (read more)
I guess I don't really buy that, though. I don't think that a norm specifically against public bets that are ghoulish from a common-sense morality perspective would place very important limitations on the community's ability to form accurate beliefs or do good.

Responding to this point separately: I am very confused by this statement. A large fraction of topics we are discussing within the EA community, are pretty directly about the death of thousands, often millions or billions, of other people. From biorisk (as discussed here), to global health and development, to the risk of major international conflict, a lot of topics we think about involve people forming models that will quite directly require forecasting the potential impacts of various life-or-death decisions.

I expect bets about a large number of Global Catastrophic Risks to be of great importance, and to similarly be perceived as "ghoulish" as you describe here. Maybe you are describing a distinction that is more complicated than I am currently comprehending, but I at least would expect Chi and Greg to object to bets of the type "what is the expected number of people dying in self-driving car... (read more)

There might also be a confusion about what the purpose and impact of bets in our community is. While the number of bets being made is relatively small, the effect of having a broader betting culture is quite major, at least in my experience of interacting with the community.

More precisely, we have a pretty concrete norm that if someone makes a prediction or a public forecast, then it is usually valid (with some exceptions) to offer a bet with equal or better odds than the forecasted probability to the person making the forecast, and expect them to take you up on the bet. If the person does not take you up on the bet, this usually comes with some loss of status and reputation, and is usually (correctly, I would argue) interpreted as evidence that the forecast was not meant sincerely, or the person is trying to avoid public accountability in some other way. From what I can tell, this is exactly what happened here.

The effects of this norm (at least as I have perceived it) are large and strongly positive. From what I can tell, it is one of the norms that ensures the consistency of the models that our public intellectuals express, and when I interact with communities that do not have t... (read more)

This doesn't affect your point, but I just wanted to note that the post—including the wonderful title—was written by Alex Tabarrok.
Oops. Fixed.
I think what's confusing you is that people are selectively against betting based on its motivation. In EA, people regularly talk about morbid topics, but the stated aim is to help people. In this case, the aim could be read as "having fun and making money". It was the motivation that was a problem, not the act itself, for most people.

While my read of your post is "there is the possibility that the aim could be interpreted this way" which I regard as fair, I feel I should state that 'fun and money' was not my aim, and (I strongly expect not Justin's), as I have not yet done so explicitly.

I think it's important to be as well-calibrated as reasonably possible on events of global significance. In particular, I've been seeing a lot of what appear to me to be poorly calibrated, alarmist statements, claims and musings on nCOV on social media, including from EAs, GCR researchers, Harvard epidemiologists, etc. I think these poorly calibrated/examined claims can result in substantial material harms to people, in terms of stoking up unnecessary public panic, confusing accurate assessment of the situation, and creating 'boy who cried wolf' effects for future events. I've spent a lot of time on social media trying to get people to tone down their more extreme statements re: nCOV.

(edit: I do not mean this to refer to Justin's fermi estimate, which was on the more severe end but had clearly reasoned and transparent thinking behind it; more a broad comment on concerns re: ... (read more)

Following Sean here I'll also describe my motivation for taking the bet.

After Sean suggested the bet, I felt as if I had to take him up on it for group epistemic benefit; my hand was forced. Firstly, I wanted to get people to take the nCOV seriously and to think thoroughly about it (for the present case and for modelling possible future pandemics) - from an inside view model perspective the numbers I was getting are quite worrisome. I felt that if I didn't take him up on the bet people wouldn't take the issue as seriously, nor take explicitly modeling things themselves as seriously either. I was trying to socially counter what sometimes feels like a learned helplessness people have with respect to analyzing things or solving problems. Also, the EA community is especially clear thinking and I think a place like the EA forum is a good medium for problem solving around things like nCOV.

Secondly, I generally think that holding people in some sense accountable for their belief statements is a good thing (up to some caveats); it improves the collective epistemic process. In general I prefer exchanging detailed models in discussion rather than vague intuitions mediated by ... (read more)

I'm so sorry Sean, I took it as obvious that your motivation was developing accurate beliefs, hopefully to help you help others, rather than fun and profit. Didn't mean to imply otherwise!
Thanks Khorton, nothing to apologise for. I read your comment as a concern about how the motivations of a bet might be perceived from the outside (whether in the specific case or more generally); but this led me to the conclusion that actually stating my motivations rather than assuming everyone reading knows would be helpful at this stage!
I would be interested to learn more about your views on the current outbreak. Can you link to the statements you made on social media, or present your perspective here (or as a top-level comment or post)?
Hi Wei, Sorry I missed this. My strongest responses over the last while have fallen into the categories of: (1) responding to people claiming existential risk-or-approaching potential (or sharing papers by people like Taleb stating we are entering a phase where this is near-certain; e.g. https://static1.squarespace.com/static/5b68a4e4a2772c2a206180a1/t/5e2efaa2ff2cf27efbe8fc91/1580137123173/Systemic_Risk_of_Pandemic_via_Novel_Path.pdf [https://static1.squarespace.com/static/5b68a4e4a2772c2a206180a1/t/5e2efaa2ff2cf27efbe8fc91/1580137123173/Systemic_Risk_of_Pandemic_via_Novel_Path.pdf] (shared in one xrisk group, for example, as "X-riskers, it would appear your time is now: "With increasing transportation we are close to a transition to conditions in which extinction becomes certain both because of rapid spread and because of the selective dominance of increasingly worse pathogens.". My response: "We are **not** "close to a transition to conditions in which extinction becomes certain both because of rapid spread and because of the selective dominance of increasingly worse pathogens".) Or, responding to speculation that nCov is a deliberately developed bioweapon, or was accidentally released from a BSL4 lab in Wuhan. There isn't evidence for either of these and I think they are unhelpful types of speculation to be made without evidence, and such speculations can spread widely. Further, some people making the latter speculation didn't seem to be aware what a common class of virus coronaviruses are (ranging from common cold thru to SARS). Whether or not a coronavirus was being studied at the Wuhan lab, I think it would not be a major coincidence to find a lab studying a coronavirus in a major city. A third example was clarifying that the event 201 exercise Johns Hopkins did (which involved 65 million hypothetical deaths) was a tabletop simulation , not a prediction, and therefore could not be used to extrapolate an expectation of 65 million deaths from the current o

To clarify a bit, I'm not in general against people betting on morally serious issues. I think it's possible that this particular bet is also well-justified, since there's a chance some people reading the post and thread might actually be trying to make decisions about how to devote time/resources to the issue. Making the bet might also cause other people to feel more "on their toes" in the future, when making potentially ungrounded public predictions, if they now feel like there's a greater chance someone might challenge them. So there are potential upsides, which could outweigh the downsides raised.

At the same time, though, I do find certain kinds of bets discomforting and expect a pretty large portion of people (esp. people without much EA exposure) to feel discomforted too. I think that the cases where I'm most likely to feel uncomfortable would be ones where:

  • The bet is about an ongoing, pretty concrete tragedy with non-hypothetical victims. One person "profits" if the victims become more numerous and suffer more.

  • The people making the bet aren't, even pretty indirectly, in a position to influence the management of the tragedy or the dedication of resources to it. It does

... (read more)
The people making the bet aren't, even pretty indirectly, in a position to influence the management of the tragedy or the dedication of resources to it. It doesn't actually matter all that much, in other words, if one of them is over- or under-confident about some aspect of the tragedy.

Do you think the bet would be less objectionable if Justin was able to increase the number of deaths?

5Ben Garfinkel3y
No, I think that would be far worse. But if two people were (for example) betting on a prediction platform that's been set up by public health officials to inform prioritization decisions, then this would make the bet better. The reason is that, in this context, it would obviously matter if their expressed credences are well-callibrated and honestly meant. To the extent that the act of making the bet helps temporarily put some observers "on their toes" when publicly expressing credences, the most likely people to be put "on their toes" (other users of the platform) are also people whose expressed credences have an impact. So there would be an especially solid pro-social case for making the bet. I suppose this bullet point is mostly just trying to get at the idea that a bet is better if it can clearly be helpful. (I should have said "positively influence" instead of just "influence.") If a bet creates actionable incentives to kill people, on the other hand, that's not a good thing.
Thanks bmg. FWIW, I provide my justification (from my personal perspective) here: https://forum.effectivealtruism.org/posts/g2F5BBfhTNESR5PJJ/concerning-the-recent-wuhan-coronavirus-outbreak?commentId=mWi2L4S4sRZiSehJq [https://forum.effectivealtruism.org/posts/g2F5BBfhTNESR5PJJ/concerning-the-recent-wuhan-coronavirus-outbreak?commentId=mWi2L4S4sRZiSehJq]
9Ben Garfinkel3y
Thanks! I do want to stress that I really respect your motives in this case and your evident thoughtfulness and empathy in response to the discussion; I also think this particular bet might be overall beneficial. I also agree with your suggestion that explicitly stating intent and being especially careful with tone/framing can probably do a lot of work. It's maybe a bit unfortunate that I'm making this comment in a thread that began with your bet, then, since my comment isn't really about your bet. I realize it's probably pretty unpleasant to have an extended ethics debate somehow spring up around one of your posts. I mainly just wanted to say that it's OK for people to raise feelings of personal/moral discomfort and that these feelings of discomfort can at least sometimes be important enough to justify refraining from a public bet. It seemed to me like some of the reaction to Chi's comment went too far in the opposite direction. Maybe wrongly/unfairly, it seemed to me that there was some suggestion that this sort of discomfort should basically just be ignored or that people should feel discouraged from expressing their discomfort on the EA Forum.
The US government attempted to create a prediction market to predict terrorist attacks [https://en.wikipedia.org/wiki/Policy_Analysis_Market]. It was shut down basically because it was perceived as “ghoulish”. My impression is that experts think [https://www.mitpressjournals.org/doi/10.1162/itgg.2007.2.3.73] that shutting down the market made terrorism more likely, but I’m not super well-informed. I see this as evidence both that 1) markets are useful and 2) some people (including influential people like senators) react pretty negatively to betting on life or death issues, despite the utility.
5Ben Garfinkel3y
Just as an additional note, to speak directly to the examples you gave: I would personally feel very little discomfort if two people (esp. people actively making or influencing decisions about donations and funding) wanted to publicly bet on the question: "What is the likelihood of this new bednet distribution method outperforming existing methods by more than 30%, saving 30000 additional people over the next year?" I obviously don't know, but I would guess that Chi and Greg would both feel more comfortable about that question as well. I think that some random "passerby" might still feel some amount of discomfort, but probably substantially less. I realize that there probably aren't very principled reasons to view one bet here as intrinsically more objectionable than others. I listed some factors that seem to contribute to my judgments in my other comment, but they're obviously a bit of a hodgepodge. My fully reflective moral view is also that there probably isn't anything intrinsically wrong with any category of bets. For better or worse, though, I think that certain bets will predictably be discomforting and wrong-feeling to many people (including me). Then I think this discomfort is worth weighing against the plausible social benefits of the individual bet being made. At least on rare occasions, the trade-off probably won't be worth it. I ultimately don't think my view here is that different than common views on lots of other more mundane social norms. For example: I don't think there's anything intrinsically morally wrong about speaking ill of the dead. I recognize that a blanket prohibition on speaking ill of the dead would be a totally ridiculous and socially/epistemically harmful form of censorship. But it's still true that, in some hard-to-summarize class of cases, criticizing someone who's died is going to strike a lot of people as especially uncomfortable and wrong. Even without any specific speech "ban" in place, I think that it's worth giving weight to
purely because they thought it'd be fun to win a bet and make some money off a friend.

I do think the "purely" matters a good bit here. While I would go as far as to argue that even purely financial motivations are fine (and should be leveraged for the public good when possible), I think in as much as I understand your perspective, it becomes a lot less bad if people are only partially motivated by making money (or gaining status within their community).

As a concrete example, I think large fractions of academia are motivated by wanting a sense of legacy and prestige (this includes large fractions of epidemiology, which is highly relevant to this situation). Those motivations also feel not fully great to me, and I would feel worried about an academic system that tries to purely operate on those motivations. However, I would similarly expect an academic system that does not recognize those motivations at all, bans all expressions of those sentiments, and does not build system that leverages them, to also fail quite disastrously.

I think in order to produce large-scale coordination, it is important to enable the leveraging a of a large variety of motivations, while also keeping them in check by ensuring at least a minimum level of more aligned motivations (or some other external systems that ensures partially aligned motivations still result in good outcomes).

I strongly disagree with this comment - I think that motivations matter and that betting with an appropriate respect for the people who have died is completely possible - but I am glad you stated your position explicitly. Comments like this make the Forum better.

I would similarly be curious to understand the level of downvoting of my comment offering to remove my comments in light of concerns raised and encouragement to consider doing so. This is by far the most downvoted comment I've ever had. This may just be an artefact of how my call for objections to removing my comments has manifested (I was anticipating posts stating an objection like Ben's and Habryka's, and for those to be upvoted if popular, but people may have simply expressed objection by downvoting the original offer). In that case that's fine.

Another possible explanation is an objection to me even making the offer in the first place. My steelman for this is that even the offer of self-censorship of certain practices in certain situations could be seen as coming at a very heavy cost to group epistemics. However from an individual-posting-to-forum perspective, this feels like an uncomfortable thing to be punished for. Posting possibly-controversial posts to a public forum has some unilateralist's curse elements to it: risk is distributed to the overall forum, and the person who posts the possibly-controversial thing is likely to be someone who deems the... (read more)

Ah, I definitely interpreted your comment as “leave a reply or downvote if you think that’s a bad idea”. So I downvoted it and left a reply. My guess is many others have done the same for similar reasons. I do also think editing for tone was a bad idea (mostly because I think the norm of having to be careful around tone is a pretty straightforward tax on betting, and because it contributed to the shaming of people who do want to bet for what Chi expressed as “inappropriate“ motivations), so doing that was a concrete thing that I think was bad on a norm level.
Thanks, good to know on both, appreciate the feedback.
5Ben Pace3y
(+1 to Oli's reasoning - I have since removed my downvote on that comment.)
I'm happy to remove my comments; I think Chi raises a valid point. The aim was basically calibration. I think this is quite common in EA and forecasting, but agree it could look morbid from the outside, and these are publicly searchable. (I've also been upbeat in my tone for friendliness/politeness towards people with different views, but this could be misread as a lack of respect for the gravity of the situation). Unless this post receives strong objections by this evening, I will delete my comments or ask moderators to delete.

I also strongly object. I think public betting is one of the most valuable aspects of our culture, and would be deeply saddened to see these comments disappear (and more broadly as an outside observer, seeing them disappear would make me deeply concerned about the epistemic health of our community, since that norm is one of the things that actually keeps members of our community accountable for their professed beliefs)

My take is that this at this stage has been resolved in favour of "editing for tone but keeping the bet posts". I have done the editing for tone. I am happy with this outcome, I hope most others are too.

My own personal view is that I think public betting on beliefs is good - it's why I did it (both this time and in the past) and my preference is to continue doing so. However, my take is that that the discussion highlighted that in certain circumstances around betting (such as predictions on events such as an ongoing mass fatality event) it is worth being particularly careful about tone.

I strongly object to saying we're not allowed to bet on the most important questions - questions of life or death. That's like deciding to take the best person off the team defending the president. Don't handicap yourself when it matters most. This is the tool that stops us from just talking hot air and actually records which people are actually able to make correct predictions. These are some of the most important bets on the forum.

(Kind of just a nitpick)

I think I strongly agree with you on the value of being open to using betting in cases like these (at least in private, probably in public). And if you mean something like "Just in case anyone were to interpret Chi a certain way, I'd like to say that I strongly object to...", then I just fully agree with your comment.

But I think it's worth pointing out that no one said "we're not allowed to" do these bets - Chi's comment was just their personal view and recommendation, and had various hedges. At most it was saying "we shouldn't", which feels quite different from "we're not allowed to".

(Compare thinking that what someone is saying is racist and they really shouldn't have said it, vs actually taking away their platforms or preventing their speech - a much higher bar is needed for the latter.)

Personally, I don't see the bet itself as something that shouldn't have happened. I acknowledge that others could have the perspective Chi had, and can see why they would. But didn't feel that way myself, and I personally think that downside is outweighed by the upside of it being good for the community's epistemics - and this is not just for Justin and Sean, but also for people reading the comments, so that they can come to more informed views based on the views the betters' take and how strongly they hold them. (Therefore, there's value in it being public, I think - I also therefore would personally suggest the comments shouldn't be deleted, but it's up to Sean.)

But I did feel really weird reading "Pleasure doing business Justin!". I didn't really feel uncomfortable with the rest of the upbeat tone Sean notes, but perhaps that should've been toned down too. That tone isn't necessary for the benefits of the bet - it could be civil and polite but also neutral or sombre - and could create reputational issues for EA. (Plus it's probably just good to have more respectful/taking-things-seriously norms in cases like these, without having to always calculate the consequences of such norm

... (read more)
I agree that Chi's comment is very reasonable (and upvoted for that reason). Personally, I think editing for tone would be a reasonable compromise, but I am glad people are starting to think more about the EA Forum as a publicly searchable space.
Re: Michael & Khorton's points, (1) Michael fully agreed, casual figure of speech that I've now deleted. I apologise. (2) I've done some further editing for tone but would be grateful if others had further suggestions. I also agree re: Chi's comment - I've already remarked that I think the point was valid, but I would add that I found it to be respectful and considerate in how it made its point (as one of the people it was directed towards). It's been useful for me to reflect on. I think a combination of two things for me: one is some inherent personal discomfort/concern about causing offence by effectively saying "I think you're wrong and I'm willing to bet you're wrong", which I think I unintentionally counteracted with (possibly excessive) levity. The second is how quickly the disconnect can happen from (initial discussion of very serious topic) to (checking in on forum several days later to quickly respond to some math). Both are things I will be more careful about going forward. Lastly, I may have been spending too much time around risk folk, for whom certain discussions become so standard that one forgets how they can come across.

Fwiw, the "pleasure doing business" line was the only part of your tone that struck me as off when I read the thread.

I guess there's an interesting argument here for making casual gambling illegal--based on this thread, it seems like "Bets are serious & somber business, not for frivolous things like horse races" could be a really high value meme to spread.
Metaculus [https://www.metaculus.com/questions/3530/how-many-people-will-die-as-a-result-of-the-2019-novel-coronavirus-covid-19-before-2021/] currently gives a 16% chance to the claim that total deaths before 2021 will be greater than 11.6 M.
I must admit, I would not make the same bet at the same odds on the 27th of February 2020.
If the death rate is really that high, then we should significantly update P(it goes world scale pandemic) and P(a particular person gets it | it goes world scale pandemic) downwards as it would cause governments and individuals to put a lot of resources towards prevention. One can also imagine that P(a particular person dies from it | a particular person gets it) will go down with time as resources are spent on finding better treatment and a cure.
Good points! I agree but I'm not sure how significant those effects will be though... Have an idea of how we'd in a principled precise way update based on those effects?
It's difficult. You'd probably need a model of every country since state capacity, health care, information access... can vary widely.
It looks like it almost not affecting children; a person of older age should give himself a higher estimate of being affected.
4Peter Wildeford3y
What do you base this one on?
~1/6 of the world population were infected by the 2009 swine flu [https://en.wikipedia.org/wiki/2009_flu_pandemic] (mortality rate was much lower though, at ~1/3000 of those infected).
I base it on what Greg mentions in his reply about the swine flu and also the reasoning that the reproduction number has to go below 1 for it to stop spreading. If its normal reproduction number before people have become immune (after being sick) is X (like 2 say), then to get the reproduction number below 1, (susceptible population proportion) * (normal reproduction number) < 1. So with a reproduction number of 2 the proportion who get infected will be 1/2. This assumes that people have time to become immune so for a fast spreading virus more than that proportion would fall ill (note thought that pointing in the opposite direction is the effect that not everyone is uniformly likely to get ill though because some people are in relative isolation or have very good hygiene).
Just a note that the reproduction number can decrease for other reasons; in particular if and as the disease spreads you might expect greater public awareness, CDC guidance, travel bans, etc leading to greater precaution and less opportunity for infected individuals to infect others.
3Jess Kinchen Smith3y
How do you arrive at 1/3 here?
It's based on a few facts and swirling them around in my intuition to choose a single simple number. Long invisible contagious incubation period (seems somewhat indicated but maybe is wrong) and high degree of contagiousness (the Ro factor) implies it is hard to contain and should spread in the network (and look something like probability spreading in a Markov chain with transition probabilities roughly following transportation probabilities). The exponential growth implies that we are only a few doublings away from world scale pandemic (also note we're probably better at stopping things when their at small scale). In the exponential sense, 4,000 is half way between 1 and 8 million and about a third of the way to world population.
The exponential growth curve and incubation period also have implications about "bugging out" strategies where you get food and water, isolate, and wait for it to be over. Let's estimate again: Assuming as in the above comment we are 1/3 of the exponential climb (in reported numbers) towards the total world population and it took a month, in two more months (the end of March) we would expect it to reach saturation. If the infectious incubation period is 2 weeks (and people are essentially uniformly infectious during that time) then you'd move the two month date forward by two weeks (the middle of March). Assuming you don't want to take many risks here you might have a week buffer in front (the end of the first week of March). Finally, after symptoms arise people may be infectious for a couple weeks (I believe this is correct, anyone have better data?). So the sum total amount of time for the isolation strategy is about 5 weeks (and may start as early as the end of the first week of March or earlier depending on transportation and supply disruptions). Governments by detecting cases early or restricting travel, and citizens by isolating and using better hygiene, could change these numbers and dates. (note: for future biorisks that may be more severe this reasoning is also useful)
Have you looked at how long pandemics have lasted in the past? I think it's a lot longer than five weeks.
It could have longer tail, but given high R0 large part of human population could be simultaneously ill (or self isolated) in March-April 2020. What is you opinion, Dave, could this could put food production at risk?
2Jess Kinchen Smith3y
Thanks. I've updated towards your estimate but 1/3 still seems high by my (all too human) intuitions.

I did some research on hand hygiene and wrote a quick summary on Facebook and LessWrong if anyone is interested. Not sure it's really appropriate for a top-level post on the EA Forum but I do think it's pretty useful to know. Most people (including me a few days ago) are very bad at washing their hands.

For a week or so I have been fearing this potentially deadly disease spreading to most people on Earth (space-station and antarctic bases excepted), since the doubling time has been about half a week, and simple calculations show that even with a 1 week doubling time, half the Earth's population would get it by June.  My fears were confirmed by reading of the John Hopkins Event 201 simulation last year, in which a 1 week doubling time virus spread throughout the world and killed tens of millions of people:

https://www.abc.net.au/news/2020-02-... (read more)

Some slightly positive evidence: By the 24th, 19 cases had been reported outside of China, with onset of symptoms usually before that. Given the most recent estimate of a mean incubation period of 5 days, it seems surprising that only 1 of the 19 cases has infected another person that we know of so far (a man traveling from Wuhan to Vietnam infected his son, who shared a hotel room with his father for 3 days). Since monitoring of people the infected came into contact with is high, finding infected people should be fairly quick.

Seems that effective contain... (read more)

The possibility of a long incubation period (and especially a long-ish pre-symptomatic infectiousness period) is especially worrying to me, as my impression is that this was a key reason SARS didn't take off more than it did.

That said, I'm not sure it's clear yet that there is a long pre-symptomatic period. This article suggests we're not really sure about this yet. I'm expecting to get more information very soon, though.

Update: "A WHO panel of 16 independent experts twice last week declined to declare an international emergency over the outbreak.

"While more cases have been emerging outside China in people who have travelled from there recently, the WHO said only one of the overseas cases involved human-to-human transmission."


The WHO has now declared a global health emergency. https://www.bbc.com/news/world-51318246 [https://www.bbc.com/news/world-51318246]
There has now been an incidence of person-to-person transmission outside China

How confident are you that it affects mainly older people or those with preexisting health conditions? Are the stats solid now? I vaguely recall that SARS and MERS (possibly the relevant reference class), were age agnostic.

Here's a chart of odds of death by age that was tweeted by an epidmiology professor at Hopkins. I can't otherwise vouch for the reliability of the data and caveat that mortality data sucks this early in an epidemic. https://twitter.com/JustinLessler/status/1222108497556279297 [https://twitter.com/JustinLessler/status/1222108497556279297]
Nice find! Hopefully it updates soon as we learn more. What is your interpretation of it in terms of mortality rate in each age bracket?
MERS was pretty age-agnostic. SARS had much higher mortality rates in >60s. All the current reports from China claim that it affects mainly older people or those with preexisting health conditions. Coronavirus is a broad class including everything from the common cold to MERS; not sure there's good ground to anchor too closely to SARS or MERS as a reference class.

When comparing the novel coronavirus to the seasonal flu, it seems like the main differences are:

-the seasonal flu is typically around half as infectious (r0 typically 1.4 to 1.6)

-some strains of seasonal flu have a vaccine available; the coronavirus doesn't yet (although quick progress has apparently been made on the first steps)

But we believe that both seasonal flu and this coronavirus are similarly deadly, largely for the same segment of the population (older/at risk). Have I summarised this correctly?

I don't think this is a good summary for an important reason: I think the Wuhan Coronavirus is a few orders of magnitude more deadly than a normal seasonal flu. The mortality estimates for the Wuhan Coronavirus are in the single digit percentages, whereas this source tells me that the seasonal flu mortality rate is about 0.014%. [ETA: Sorry, it's closer to 0.1%, see Greg Colbourn's comment].

A better comparison would be to look at death rate for those infected: ~0.1% for seasonal flu.

The mortality rate is the proportion of infections that *ultimately* result in death. If we had really good data (we don't), we could get a better estimate by pitting fatalities against *recoveries*. Since we aren't tracking recoveries well, If we attempt to compute mortality rates right now (as infections are increasing exponentially), we're going to badly underestimate the actual mortality rate.
The source you're looking at considers everyone in the population, even people who don't get the flu, but the 3% figure for the Wuhan Coronavirus is only considering the people who have been infected. EDIT: I was wrong, your source is giving the percentage of deaths caused by the flu, not the percentage of the whole population killed by flu each year. The annual death toll in China is 8.9 million, so 87 deaths would mean 0.00001% are caused by the Wuhan Coronavirus, compared to 0.014% for the seasonal flu. (I don't think this is a great way to compare, because very few people have been exposed to the Coronavirus so far, but you get the gist.)

The opposite trend occurred for SARS (in the same class as nCoV-2019), which originally had around a 2-5% deaths/cases rate but ended up with >10% once all cases ran their full course.

SARS was very unusual, and serves as a partial counterexample. On the other hand, the "trend" being shown is actually almost entirely a function of the age groups of the people infected - it was far more fatal in the elderly. With that known now, we have a very reasonable understanding of what occurred - which is that because the elderly were infected more often in countries where SARS reached later, and the countries are being aggregated in this graph, the raw estimate behaved very strangely.
I think we were both confused. But based on what Greg Colbourn said, my point still stands, albeit to a weaker extent.

Note that there is now a Metaculus prize for questions and comments related to the coronavirus outbreak. Here you can see the existing questions in this series.

I'am checking all stats nearly every hour at https://www.coronavirus-symptoms.info

Would love for someone to poke this & assess its epistemics: Coronavirus Contains "HIV Insertions", Stoking Fears Over Artificially Created Bioweapon (a)

I'm more curious about the trustworthiness of the scary graphs than about the claims that it may have been bioengineered.

Cleared up here [https://www.facebook.com/groups/eahangout/permalink/2797419100344996/?comment_id=2812386792181560] on the EA Hangouts fb group.

Any thoughts on why the estimates here are so much higher than metaculus? Here they seem to range between 10 - 100 million, whilst the current metaculus median is 100k.

Maybe I've missed something.

Maybe because of anchoring effect: everyone on metaculus sees the median prediction before he makes the bet and doesn't want to be much different from the group.

How are you including age in this regression? It seems to me that ADRS resulting in ICU admission is a candidate for confounding with age.