Mathematical model for Covid-19 explained by Numberphile

For those of you who like math and have at least a passing acquaintance with differential equations Numberphile has just posted a special episode on how mathematical modeling works with the Covid-19 projections. It shows exactly how “flattening the curve” looks and which parameters affect the outcome. It is worth a look, and is instructive even if you can’t solve a differential equation. In fact this video uses free software to do it.


Thanks. I hope this starts a good discussion.

Although not in the video, the key characteristics of the response, the maximal fraction infected is governed largely by Ro and for is scarcely affected by Io, for practical values. This effective independence of the response wrt Io is tells you that for any finite Io the epidemic will ensue and have the same salient properties. A perfect wall can keep the epidemic out, but an imperfect one doesn’t do much of anything.

And the difference in Ro for COVID-19 versus seasonal influenza answers all sorts of questions about why we are taking much stronger measures about the former that we have for the latter.

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I don’t and I don’t(to be honest, I don’t even recognize some of the nomenclature you and @dvdjs use) but I’ll watch anyway and chalk it up as an exercise in humility. The world needs ditch diggers, too.

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I’ve seen this pop up in my recommended feed (I’ve watched my fair share of numberphile videos!) and have been meaning to watch it. Thank you for sharing!

That was an interesting video for mathematical modeling but the link to Corona virus is only in the title. It could have been for any virus and they used the term “naive assumptions” a few times when talking about their model. That’s fine, “youtube-ers” need to label their video in such a way to get views and Corona Virus will do that at this point in time. No, i am not criticizing the video itself but if anyone thinks that is the video to watch for the actual model being used by the authorities then they are mistaken. It is more of a basics of mathematical modeling video and if viewed in that light then it is enjoyable if you like math.

been looking at the math myself and recently following what real virologists (w/ decades of experience in the area) have been saying about the issue

bottom line in the real world when r0 (i.e. “r naught” which is the number of people that become infected),… is greater than one the disease will spread

said another way,… the higher the r0 the more contagious the covid-19 virus is (and FWIW the reason covid-19 spread so rapidly is because it looks like the r0 value is greater than three, which means one individual who catches the virus can in effect pass it along to three other people)

realistically until there is heard immunity or a vaccine developed, people will be at risk of contracting an illness,… which will have knock on effects that simple math models do not take into account (for example)

so the only strategy an individual or group can do, is look for ways to think about ways to decrease r0

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