5 ms·

If you are looking for convincing evidence in favour of mask wearing - this paper is not it. It bases its conclusion on a few hundred cases in the German city

If you are looking for convincing evidence in favour of mask wearing - this paper is not it. It bases its conclusion on a few hundred cases in the German city of Jena back in April. In fact, the authors themselves apply the same analysis to other cities over the same time period (figure S15 in the supplementary material) and those plots show hardly any effect. However... if a paper claims to support X and the paper is bad, then that does not mean that X is incorrect. And given government advice around the world, it seems pretty clear that masks are understood to do more good than harm.

parineum 6y ago
> And given government advice around the world, it seems pretty clear that masks are understood to do more good than harm. That's an appeal to authority. It also doesn't mean it's incorrect but it's not evidence of anything.
- prof-dr-ir 6y ago
  I used 'understood' because it is what I believe the scientific consensus to be. Since I do not use this for anything else, there is no 'appeal to authority' in my original comment. That said, let me double down and state that I wholeheartedly recommend using the scientific consensus as a prior for your opinion on any given topic. :)
- krageon 6y ago
  An appeal to authority is a good reason to believe something if the authority can be understood to be knowledgeable. It's especially useful in cases where your readers can't all be expected to understand the nuances of the decision making involved and you want to avoid appealing to emotions (which works better). What basically never works are appeals to logic, frequently even here (a place which explicitly stimulates it). The reasons for why it doesn't work here (miles of text with pedantic arguing, usually not a lot of substance) are different for why it won't work in public (people don't feel like doing that with you, usually) but they are there. Especially in a case such as this an appeal to authority can be useful, as there is a big bad-faith storm of "discussion" surrounding the subject that really isn't doing anyone any favours.
  - dtech 6y ago
    True, but you can never use it to prove that something works, especially in a case like this where governments are acting under time and information constraints.
    - TLightful 6y ago
      Use the force, Luke.
  - mbar84 6y ago
    It is not enough for the authority to be knowledgeable, their incentives must also be aligned. If people appeal to the authority to do something, then it may do whatever is expedient regardless of merit. With limited knowledge, I'm inclined to go along with measures that are low cost and have a plausible explanation wrt. effectiveness. That being said, if the mask situation has shown us anything, it's that the authorities are neither trustworthy nor competent.
    - xg15 6y ago
      What would be an example of misaligned incentives in the case of mask wearing? A fabric maker conspiracy? How did the mask situation show that authorities are not trustworthy or competent?
- threatofrain 6y ago
  When you trust your doctor or lawyer, you're also appealing to authority. It's not wrong for a person on the ground to look to various national/international institutions as signal (evidence) for a hypothesis, and to adjust as their life experience guides them.
- celticninja 6y ago
  It would be if the reason the advice was given by governments was NOT at the behest of doctors/scientists fighting the pandemic. However it is, so in this case the governments are just the messenger best able to broadcast the message and ensure a high level of compliance.
- raverbashing 6y ago
  "Appeal to Authority" is a crap fallacy (or maybe a crap name for a fallacy). "Appeal to hierarchy" might be a better description. Otherwise going to a doctor for a sickness, or hiring an engineer to build a house would be fallacious as well. (And give the amounts of PhDs that are incompetent or just crazy in areas they should know better is astounding but I digress)
  - viraptor 6y ago
    It's... Either badly named or applied without nuance. It's not about situations like "they're an expert on X, therefore I trust their opinion on X". Instead it's for "they're an authority on something, therefore if they have opinion on X, I should trust it".
  - thedanbob 6y ago
    It’s not a crap fallacy, it just doesn’t always apply. It’s a fallacy only in the case that you are trying to establish a strictly logical argument (in the mathematical sense). “You should do this because that expert said so” is a rational argument, not a logical one.
  - BaronSamedi 6y ago
    Your are conflating what is practical with what is true in logic and argumentation. It is practical to accept our doctor's diagnosis because we trust that the medical system produces competent doctors and because of constraints on our time. If you claimed that a diagnosis must be true because it came from a doctor then you would appealing to authority.
    - deleted 6y ago
      [deleted]
- mam2 6y ago
  I'm pretty sure at some point in history most governements were aligned to say that homosexuality is a mental disease. Don't trust anyone but yourself.
admissionsguy 6y ago
There cannot be "convincing evidence for mask wearing" for most thresholds of "convincing", can there? Since no clear difference in infections or mortality has been observed between places with different mask rules (and timings of their imposition), the effect must be either very small (in either direction) or none.
- regularfry 6y ago
  https://www.cdc.gov/mmwr/volumes/69/wr/pdfs/mm6947e2-H.pdf https://www.cdc.gov/mmwr/volumes/69/wr/pdfs/mm6947e2-H.pdf isn't subtle. You can make the argument that it might not be the wearing of masks specifically that's responsible for the difference here, but the weaker argument - that it's worth being the sort of area that will introduce mask wearing because whatever is going on is correlated with it - still works.
  - endless1234 6y ago
    Exactly. It's hard to see how masks themselves could have a negative effect. If they have a positive effect caused by people being more conscious of the current situation and keeping a greater distance, or not going out at all because having to wear a mask is a burden, so what? Worst case is they are neutral all things considered.
    - makomk 6y ago
      It may be hard to see how masks themselves have a negative effect, but it's easy to see how mask wearing as a medical intervention in the real world could. All it would take is people being willing to stand slightly closer together or take slightly more risks because they believed masks were effective protection.
      - mdorazio 6y ago
        As a counterpoint and to reiterate the parent comment's point, masks are a stark visual reminder that you need to practice other measures like social distancing and going out less. I'd be willing to bet that masks increase likelihood of practicing safe pandemic measures due to a "top of mind" effect rather than decrease them due to a false sense of safety.
klmr 6y ago
The description of S15 gives a plausible explanation of why the effect is much less for some of these city than for Jena. Of course this is speculation but this doesn’t mean that fig S15 disproves the paper’s finding. And for Jena the effect is extraordinarily strong, and well controlled for. I’m not aware of any alternative explanation (to mask-wearing) which could explain this effect, and until I hear such an explanation I consider this strong evidence for the effect of mask-wearing on COVID-19 transmission. This study isn’t the only evidence for the effectiveness of mask-wearing but it’s certainly part of the overall evidence, and I’d like to hear better arguments for calling it “bad”.
- lixtra 6y ago
  I found someone on the internet who said they prayed for Weimar, a smaller neighbor city of Jena. Luckily you can use the same mechanics of the study to grasp the effects of their prayer. It worked similarly well[1] as masks in Jena[2]. Jena is a single data point supporting the effectivity of masks (there could be indirect effects at work as well, i.e. people better grasping the severity of the situation). The sophisticated average that they use as comparison makes it appear to carry more confidence than it does. [1] https://www.corona-in-zahlen.de/landkreise/sk%20weimar/ https://www.corona-in-zahlen.de/landkreise/sk%20weimar/ [2] https://www.corona-in-zahlen.de/landkreise/sk%20jena/ https://www.corona-in-zahlen.de/landkreise/sk%20jena/
  - klmr 6y ago
    > I found someone on the internet who said they prayed for Weimar, a smaller neighbor city of Jena. And that is why post-hoc hypotheses aren’t valid. It does not, however, invalidate this study. Incidentally, I found somebody who prayed for all cities except Weimar and Jena, so this neutralises your anonymous friend’s prayer.
    - lixtra 6y ago
      > And that is why post-hoc hypotheses aren’t valid. I agree on this. Can you point to where they announced the study on April 6th or before? Or did the decide to look at Jena only after the data was available? How is that not a post-hoc hypothesis? Of course, both general hypotheses of masks and prayer predate Covid19. > It does not, however, invalidate this study. No. The study contributes a single data point in favor of masks, but is not very convincing (in that the authors did not look deep into contradictions and alternative explanations) and of course not conclusive as the bad title makes it appear.
deleted 6y ago
[deleted]
oldgradstudent 6y ago
> And given government advice around the world, it seems pretty clear that masks are understood to do more good than harm. Until sometime in March or April, government advice all around the western world was that masks in community settings are ineffective and possibly dangerous (due to improper handling). Usually when these agencies change position or announce a new position, the decision is accompanied by a properly referenced whitepaper that lays out the evidence for the new position. This hasn't happened here.

parineum 6y ago

> And given government advice around the world, it seems pretty clear that masks are understood to do more good than harm. That's an appeal to authority. It also doesn't mean it's incorrect but it's not evidence of anything.

prof-dr-ir 6y ago
I used 'understood' because it is what I believe the scientific consensus to be. Since I do not use this for anything else, there is no 'appeal to authority' in my original comment. That said, let me double down and state that I wholeheartedly recommend using the scientific consensus as a prior for your opinion on any given topic. :)
krageon 6y ago
An appeal to authority is a good reason to believe something if the authority can be understood to be knowledgeable. It's especially useful in cases where your readers can't all be expected to understand the nuances of the decision making involved and you want to avoid appealing to emotions (which works better). What basically never works are appeals to logic, frequently even here (a place which explicitly stimulates it). The reasons for why it doesn't work here (miles of text with pedantic arguing, usually not a lot of substance) are different for why it won't work in public (people don't feel like doing that with you, usually) but they are there. Especially in a case such as this an appeal to authority can be useful, as there is a big bad-faith storm of "discussion" surrounding the subject that really isn't doing anyone any favours.
- dtech 6y ago
  True, but you can never use it to prove that something works, especially in a case like this where governments are acting under time and information constraints.
  - TLightful 6y ago
    Use the force, Luke.
- mbar84 6y ago
  It is not enough for the authority to be knowledgeable, their incentives must also be aligned. If people appeal to the authority to do something, then it may do whatever is expedient regardless of merit. With limited knowledge, I'm inclined to go along with measures that are low cost and have a plausible explanation wrt. effectiveness. That being said, if the mask situation has shown us anything, it's that the authorities are neither trustworthy nor competent.
  - xg15 6y ago
    What would be an example of misaligned incentives in the case of mask wearing? A fabric maker conspiracy? How did the mask situation show that authorities are not trustworthy or competent?
threatofrain 6y ago
When you trust your doctor or lawyer, you're also appealing to authority. It's not wrong for a person on the ground to look to various national/international institutions as signal (evidence) for a hypothesis, and to adjust as their life experience guides them.
celticninja 6y ago
It would be if the reason the advice was given by governments was NOT at the behest of doctors/scientists fighting the pandemic. However it is, so in this case the governments are just the messenger best able to broadcast the message and ensure a high level of compliance.
raverbashing 6y ago
"Appeal to Authority" is a crap fallacy (or maybe a crap name for a fallacy). "Appeal to hierarchy" might be a better description. Otherwise going to a doctor for a sickness, or hiring an engineer to build a house would be fallacious as well. (And give the amounts of PhDs that are incompetent or just crazy in areas they should know better is astounding but I digress)
- viraptor 6y ago
  It's... Either badly named or applied without nuance. It's not about situations like "they're an expert on X, therefore I trust their opinion on X". Instead it's for "they're an authority on something, therefore if they have opinion on X, I should trust it".
- thedanbob 6y ago
  It’s not a crap fallacy, it just doesn’t always apply. It’s a fallacy only in the case that you are trying to establish a strictly logical argument (in the mathematical sense). “You should do this because that expert said so” is a rational argument, not a logical one.
- BaronSamedi 6y ago
  Your are conflating what is practical with what is true in logic and argumentation. It is practical to accept our doctor's diagnosis because we trust that the medical system produces competent doctors and because of constraints on our time. If you claimed that a diagnosis must be true because it came from a doctor then you would appealing to authority.
  - deleted 6y ago
    [deleted]
mam2 6y ago
I'm pretty sure at some point in history most governements were aligned to say that homosexuality is a mental disease. Don't trust anyone but yourself.

admissionsguy 6y ago

There cannot be "convincing evidence for mask wearing" for most thresholds of "convincing", can there? Since no clear difference in infections or mortality has been observed between places with different mask rules (and timings of their imposition), the effect must be either very small (in either direction) or none.

regularfry 6y ago
https://www.cdc.gov/mmwr/volumes/69/wr/pdfs/mm6947e2-H.pdf https://www.cdc.gov/mmwr/volumes/69/wr/pdfs/mm6947e2-H.pdf isn't subtle. You can make the argument that it might not be the wearing of masks specifically that's responsible for the difference here, but the weaker argument - that it's worth being the sort of area that will introduce mask wearing because whatever is going on is correlated with it - still works.
- endless1234 6y ago
  Exactly. It's hard to see how masks themselves could have a negative effect. If they have a positive effect caused by people being more conscious of the current situation and keeping a greater distance, or not going out at all because having to wear a mask is a burden, so what? Worst case is they are neutral all things considered.
  - makomk 6y ago
    It may be hard to see how masks themselves have a negative effect, but it's easy to see how mask wearing as a medical intervention in the real world could. All it would take is people being willing to stand slightly closer together or take slightly more risks because they believed masks were effective protection.
    - mdorazio 6y ago
      As a counterpoint and to reiterate the parent comment's point, masks are a stark visual reminder that you need to practice other measures like social distancing and going out less. I'd be willing to bet that masks increase likelihood of practicing safe pandemic measures due to a "top of mind" effect rather than decrease them due to a false sense of safety.

klmr 6y ago

The description of S15 gives a plausible explanation of why the effect is much less for some of these city than for Jena. Of course this is speculation but this doesn’t mean that fig S15 disproves the paper’s finding. And for Jena the effect is extraordinarily strong, and well controlled for. I’m not aware of any alternative explanation (to mask-wearing) which could explain this effect, and until I hear such an explanation I consider this strong evidence for the effect of mask-wearing on COVID-19 transmission. This study isn’t the only evidence for the effectiveness of mask-wearing but it’s certainly part of the overall evidence, and I’d like to hear better arguments for calling it “bad”.

lixtra 6y ago
I found someone on the internet who said they prayed for Weimar, a smaller neighbor city of Jena. Luckily you can use the same mechanics of the study to grasp the effects of their prayer. It worked similarly well[1] as masks in Jena[2]. Jena is a single data point supporting the effectivity of masks (there could be indirect effects at work as well, i.e. people better grasping the severity of the situation). The sophisticated average that they use as comparison makes it appear to carry more confidence than it does. [1] https://www.corona-in-zahlen.de/landkreise/sk%20weimar/ https://www.corona-in-zahlen.de/landkreise/sk%20weimar/ [2] https://www.corona-in-zahlen.de/landkreise/sk%20jena/ https://www.corona-in-zahlen.de/landkreise/sk%20jena/
- klmr 6y ago
  > I found someone on the internet who said they prayed for Weimar, a smaller neighbor city of Jena. And that is why post-hoc hypotheses aren’t valid. It does not, however, invalidate this study. Incidentally, I found somebody who prayed for all cities except Weimar and Jena, so this neutralises your anonymous friend’s prayer.
  - lixtra 6y ago
    > And that is why post-hoc hypotheses aren’t valid. I agree on this. Can you point to where they announced the study on April 6th or before? Or did the decide to look at Jena only after the data was available? How is that not a post-hoc hypothesis? Of course, both general hypotheses of masks and prayer predate Covid19. > It does not, however, invalidate this study. No. The study contributes a single data point in favor of masks, but is not very convincing (in that the authors did not look deep into contradictions and alternative explanations) and of course not conclusive as the bad title makes it appear.

deleted 6y ago

[deleted]

oldgradstudent 6y ago

> And given government advice around the world, it seems pretty clear that masks are understood to do more good than harm. Until sometime in March or April, government advice all around the western world was that masks in community settings are ineffective and possibly dangerous (due to improper handling). Usually when these agencies change position or announce a new position, the decision is accompanied by a properly referenced whitepaper that lays out the evidence for the new position. This hasn't happened here.