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I am highly skeptical of this approach. Not only has this been attempted before, it appears to be on course to repeat the same technical design mistakes that ca

I am highly skeptical of this approach. Not only has this been attempted before, it appears to be on course to repeat the same technical design mistakes that caused prior attempts to fail. You can't decompose weather/climate style supercomputing models below a certain resolution because the fundamental characteristics of the computation are not meaningfully representable that way. Scalable models that correctly and efficiently capture the macro effects of many types of sparse, high-resolution dynamics require much more sophisticated computer science, systems engineering, and ways of representing data. You can't brute force it. In particular, this is a notoriously poor approach to modeling complex large-scale interactions between humans and their environments. There was a study I was involved in last year to determine why one of the epidemiological models for COVID was so badly off target. The root cause was modeling human behavior in the same way you would model weather, which is quite inappropriate but the implementors of the epidemiological model did not have the expertise to know better. The selection of GPUs is also not appropriate for the nominal objectives of the program. When modeled correctly, i.e. not as weather, these kinds of things aren't the kind of workload GPUs are good at. They tend to look more like very high dimensionality sparse graphs -- latency-hiding is more important than computational throughput. CPUs are actually quite good at this. This looks more like a program more designed to produce press releases than useful results.

alecst 6y ago
I know it's off topic but I'd love to learn more about how the modeling of COVID went wrong. You can pm me if you want to take the discussion elsewhere.
- rajansaini 6y ago
  Seconded!
- neolog 6y ago
  I would like to read about that too.
- nostromo 6y ago
  The models tended to overshoot the number of deaths by huge amounts. For example, the Imperial College of London estimated 40m deaths in 2020 instead of the 2m that occurred. https://www.wsws.org/en/articles/2020/03/18/covi-m18.html https://www.wsws.org/en/articles/2020/03/18/covi-m18.html https://www.nature.com/articles/d41586-020-01003-6 https://www.nature.com/articles/d41586-020-01003-6 https://www.imperial.ac.uk/news/196496/coronavirus-pandemic-could-have-caused-40/ https://www.imperial.ac.uk/news/196496/coronavirus-pandemic-... The model authors have since argued that the data was correct, but people responded to the pandemic by changing the way we live. That's OP point: that feedback cycles and corrections exist and they make modeling dynamic systems very difficult.
  - mattmanser 6y ago
    But they never learn either, the ICL react studies are still getting it spectacularly wrong, 4 weeks ago they claimed cases were rising in the UK, that R was above 1. Even a cursory glance at the actual data, even the data available at the time, shows they were completely and utterly wrong.
  - p1necone 6y ago
    This seems unsurprising, and the correct way to model a situation like this to me. "Lots of people could die if you keep behaving as you currently are" "Okay, lets behave differently" And then less people die. Trying to frame it as "they modelled it wrong" is nonsense. What even is the point of predictions like this if not to change behaviour - predicting outcomes based on everyone taking precautions and not telling people what might happen if they don't would be dangerous and irresponsible.
    - nostromo 6y ago
      You're missing that they modeled all of those scenarios out, "do nothing" was just one of their models. And even their best case scenarios overshot the mark -- and by a lot. This isn't to criticize modeling -- it's only to point out how hard it is to get right.
      - 6y ago
- cossatot 6y ago
  Quanta had a decent write-up of challenges faced by some researchers about a month ago: https://www.quantamagazine.org/the-hard-lessons-of-modeling-the-coronavirus-pandemic-20210128/ https://www.quantamagazine.org/the-hard-lessons-of-modeling-... Of course there are many ways that things went wrong, and not everyone made the same mistakes.
p1necone 6y ago
Of course people changed their behavior because of Covid models, that's the fucking point. The modelling wasn't wrong it was just predicting what would happen if people didn't follow any precautions, in order to work what precautions were necessary.
- zwaps 6y ago
  The models are incomplete. This is the same reason as to why Econophysics, despite all its promise and grandeur, has yet to yield any useful results. Interdependent human beings are a lot more complex entities than particles or flows.
  - richardw 6y ago
    Our emergent behaviour comes from emergent behaviour of particles, because we are them. It’s just harder to predict a few levels of emergence up.
Blikkentrekker 6y ago
> This looks more like a program more designed to produce press releases than useful results. Isn't it interesting how often one reads about science in the press that seems more geared towards generating press releases than useful results?
- FooHentai 6y ago
  Snarky, but true point. Also consider that scientific efforts geared towards attracting funding tend to be the ones that get funded. This hasn’t always been the case so it’s fair to consider what circumstances might foster a better situation, where research can be directed to areas most promising to add progress and value to society at large.
  - Blikkentrekker 6y ago
    I honestly find it rather interesting how much it is possible for scientific research to gain funding though it be completely bereft of any practical benefit for mankind, or profit margin. Consider palæontology as an entire field; there is no financial benefit nor practical application to be had for it, yet it seems to find ways to attract funding all the same, most likely because it does have a habit of generating spectacular news articles which sponsors would probably enjoy the publicity of. But there is truly no practical benefit for mankind to be had in trying to answer to what extent various dinosaur species were endothermic and feathered.
    - nyokodo 6y ago
      > But there is truly no practical benefit for mankind to be had in trying to answer to what extent various dinosaur species were endothermic and feathered. Except we’re an insatiably curious species and it sates our curiosity.
      - Blikkentrekker 6y ago
        It's a good example of how curiosity is sated not by truth, but by anything purporting as such. The image of dinosaurs that became canonically entrenched in popular culture is almost certainly completely wrong, but the truth is of little consequence, exactly because it is not used for anything that might depend on it's veracity. It really does not matter whether it be accurate or completely false, for this purpose.

alecst 6y ago

I know it's off topic but I'd love to learn more about how the modeling of COVID went wrong. You can pm me if you want to take the discussion elsewhere.

rajansaini 6y ago
Seconded!
neolog 6y ago
I would like to read about that too.
nostromo 6y ago
The models tended to overshoot the number of deaths by huge amounts. For example, the Imperial College of London estimated 40m deaths in 2020 instead of the 2m that occurred. https://www.wsws.org/en/articles/2020/03/18/covi-m18.html https://www.wsws.org/en/articles/2020/03/18/covi-m18.html https://www.nature.com/articles/d41586-020-01003-6 https://www.nature.com/articles/d41586-020-01003-6 https://www.imperial.ac.uk/news/196496/coronavirus-pandemic-could-have-caused-40/ https://www.imperial.ac.uk/news/196496/coronavirus-pandemic-... The model authors have since argued that the data was correct, but people responded to the pandemic by changing the way we live. That's OP point: that feedback cycles and corrections exist and they make modeling dynamic systems very difficult.
- mattmanser 6y ago
  But they never learn either, the ICL react studies are still getting it spectacularly wrong, 4 weeks ago they claimed cases were rising in the UK, that R was above 1. Even a cursory glance at the actual data, even the data available at the time, shows they were completely and utterly wrong.
- p1necone 6y ago
  This seems unsurprising, and the correct way to model a situation like this to me. "Lots of people could die if you keep behaving as you currently are" "Okay, lets behave differently" And then less people die. Trying to frame it as "they modelled it wrong" is nonsense. What even is the point of predictions like this if not to change behaviour - predicting outcomes based on everyone taking precautions and not telling people what might happen if they don't would be dangerous and irresponsible.
  - nostromo 6y ago
    You're missing that they modeled all of those scenarios out, "do nothing" was just one of their models. And even their best case scenarios overshot the mark -- and by a lot. This isn't to criticize modeling -- it's only to point out how hard it is to get right.
    - 6y ago
cossatot 6y ago
Quanta had a decent write-up of challenges faced by some researchers about a month ago: https://www.quantamagazine.org/the-hard-lessons-of-modeling-the-coronavirus-pandemic-20210128/ https://www.quantamagazine.org/the-hard-lessons-of-modeling-... Of course there are many ways that things went wrong, and not everyone made the same mistakes.

p1necone 6y ago

Of course people changed their behavior because of Covid models, that's the fucking point. The modelling wasn't wrong it was just predicting what would happen if people didn't follow any precautions, in order to work what precautions were necessary.

zwaps 6y ago
The models are incomplete. This is the same reason as to why Econophysics, despite all its promise and grandeur, has yet to yield any useful results. Interdependent human beings are a lot more complex entities than particles or flows.
- richardw 6y ago
  Our emergent behaviour comes from emergent behaviour of particles, because we are them. It’s just harder to predict a few levels of emergence up.

Blikkentrekker 6y ago

> This looks more like a program more designed to produce press releases than useful results. Isn't it interesting how often one reads about science in the press that seems more geared towards generating press releases than useful results?

FooHentai 6y ago
Snarky, but true point. Also consider that scientific efforts geared towards attracting funding tend to be the ones that get funded. This hasn’t always been the case so it’s fair to consider what circumstances might foster a better situation, where research can be directed to areas most promising to add progress and value to society at large.
- Blikkentrekker 6y ago
  I honestly find it rather interesting how much it is possible for scientific research to gain funding though it be completely bereft of any practical benefit for mankind, or profit margin. Consider palæontology as an entire field; there is no financial benefit nor practical application to be had for it, yet it seems to find ways to attract funding all the same, most likely because it does have a habit of generating spectacular news articles which sponsors would probably enjoy the publicity of. But there is truly no practical benefit for mankind to be had in trying to answer to what extent various dinosaur species were endothermic and feathered.
  - nyokodo 6y ago
    > But there is truly no practical benefit for mankind to be had in trying to answer to what extent various dinosaur species were endothermic and feathered. Except we’re an insatiably curious species and it sates our curiosity.
    - Blikkentrekker 6y ago
      It's a good example of how curiosity is sated not by truth, but by anything purporting as such. The image of dinosaurs that became canonically entrenched in popular culture is almost certainly completely wrong, but the truth is of little consequence, exactly because it is not used for anything that might depend on it's veracity. It really does not matter whether it be accurate or completely false, for this purpose.