Exponential growth and epidemics

A primer on exponential and logistic growth
An equally valuable form of support is to simply share some of the videos.

Excellent visualization of this kind of growth from Minutephysics and Aatish Bhatia:

Some have (quite rightfully) commented on how you shouldn't look at the R^2 of linear regressions on cumulative data since even if the changes from one day to the next are completely random, the totals they add up to wouldn't be independent of each other. Since the derivative of an exponential should also be an exponential, we could instead run the same test on the logarithms of the differences from day to day, which in this case gives R^2 = 0.91.

Thanks to these viewers for their contributions to translations
Hebrew: Omer Tuchfeld

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If you want to check it out, I feel compelled to warn you that it's not the most well-documented tool, and it has many other quirks you might expect in a library someone wrote with only their own use in mind.

Music by Vincent Rubinetti.
Download the music on Bandcamp:

Stream the music on Spotify:

If you want to contribute translated subtitles or to help review those that have already been made by others and need approval, you can click the gear icon in the video and go to subtitles/cc, then "add subtitles/cc". I really appreciate those who do this, as it helps make the lessons accessible to more people.

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Various social media stuffs:

[zerquix]

"But if no one is worrying, that's when you should worry" sums it up perfectly

[lapischicken]

"When no one is worried, that's when you should worry"

Thanks Grant

[thirukumaran]

"If people are sufficiently worried, then there's a lot less to worry about. But if no one is worried - that's when you should worry"

Brilliant summary of the exponential model.

[antstraths]

3Blue One Brown: " This growth would mean Hitting 1 million cases in 30 days (April 5th)"
World: *Hits one million cases April 4th
Me: *Impressed yet shocked

[RobertHovakimyan]

The day has come when the man who single-handedly taught us Linear Algebra is now trending on youtube.

[mapletreemon]

My man really just took the second derivative of the coronavirus

[Scum]

Inverse Tinkerbell Effect, then? The more people who believe COVID is extremely dangerous, the less dangerous it will be. When I first heard of this it was about driving safety: if everyone believes driving is dangerous, they will be more careful when driving, therefore making it more safe. But if everyone believes driving is safe, they will be less likely to be careful, therefore making it more dangerous.

[theultimatereductionist]

The spread of a virus depends on two factors:
1) How dense the population is
2) How dense the population is

[dyfcxe]

" if people are sufficiently worried, there’s much less to worry about, but if no one is worried, that’s when you should worry."
I fully agree with that. Pay attention, gentlemen.

[vlogbrothers]

I needed to see this video today. So do millions of others! Helpful, concise, unalarmist, and a good lesson in exponential growth to boot! Thank you. -John

[st-liez]

I'd like to point out that 3 weeks ago, this simulated curve showed us passing 1 million total cases on April 6th. It's April 2nd and we just did so. That really shows the power behind the exponential and how closely an epidemic follows it.

[bluebrown]

The other factor, which I was hesitant to even get into here, is the extent to which reported cases reflect real cases.

Generalizing away from epidemics, though, the key upshot is to be aware of phenomena where the rate of growth is proportional to the size of the thing growing. Compound interest, technological progress, population growth, and many other things fit this pattern, and it's shocking how bad our intuitions can be at recognizing what it means.

[georhodiumgeo]

So my buddy was driving us around and he ran a red light. I said “You just ran a red light! That’s dangerous you will get us killed.” He said “Don’t worry my brother drives like this all the time, it’s fine, people will stop for you.” A bit later he pulls up to a green light and stops. I said. “You just stopped at a green light why are we stopped at a green light” he said “You gotta be careful, you never know when my brother is coming from the other direction.”

[jasonb]

Viral outbreak appears. People: "I guess I will finally learn exponential growth mathematical models"

[mustafamalik]

Now whenever your kids ask you where they will use math in the real world, you show them this video.

[citrine]

This analysis makes a very strong case for the importance of scientific and mathematical literacy. Specifically, about the fallibility of gut feelings.

[jeffsuess]

Beautiful. I'm a math teacher who will still be in school on Monday (my province in Canada is slightly nuts), this is getting shown to all classes. You calm voice is a big help.

[ASLUHLUHC]

Moral of the story: Scare everyone into isolating themselves and always washing their hands

[richardgreen]

"If no one is worried, that is when we should worry."

[Obi-Wan_Kenobi]

Fantastic. My two greatest fears coming together.  

Disease and Math.