Desktop probability machine

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Also known as a Quincunx. Which is just a niftyer word. :slight_smile:


Francis Galton was an interesting character, you know. He was Darwin’s half-cousin, an asthmatic who self-medicated by smoking hashish, and is probably best known as the inventor of the concept of eugenics.

I can imagine a dystopia where a “Galton Board” is the government panel that decides if your genes are valuable enough to the nation to allow you to procreate. That wouldn’t fit on a desk, though.


You might enjoy a critical evaluation of of probability and population science, with a large segment addressing Galton’s Quincunx:

Krieger, N. (2012). Who and what is a “population”? Historical debates, current controversies, and implications for understanding “population health” and rectifying health inequities. The Milbank Quarterly, 90(4):634–681.


Makes me want to go plant a quincunx of poplars.

Yes, but with what resulting distribution?


Yay! Great video! No jump cuts nor annoying background music. Very watchable and interesting.

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If this was a game of Settlers of Catan there’d be a huge spike on a number I didn’t place a settlement on at the beginning.

I wish I’d had one of these a few weeks ago, when I sketched a proof of de Moivre’s Theorem for my students. (This theorem, an early precursor to the Central Limit Theorem, is the theoretical analogue of what this gizmo illustrates, that if you count heads in a sequence of flips of a fair coin the distribution tents to a normal distribution.)

Oh yes it does! Personal knowledge on that one.

And just like anything that has to do with statistics it can be easily skewed…
Is the table top you put it on really level?

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