I was always surprised at how easily you get biased sampling when generating random points despite all input - something I often saw students do was essentially

I was always surprised at how easily you get biased sampling when generating random points despite all input - something I often saw students do was essentially normalize({2rand() - 1, 2rand() - 1, 2rand() - 1}) or variations of that (where rand() is "good" not the literal rand(3)), and there are numerous other ways that are more subtly wrong. IIRC the nominally correct way for a sphere specifically is something like a=rand() b=rand() and the random point is something* like { cos(a)sin(b), sin(b), cos(a)cos(b) }[1] I think the best illustration of "reasonable choices of what random values should be used leading to biased results" is Bertrand's paradox which I was introduced to via numberphile/3blue1brown: https://www.youtube.com/watch?v=mZBwsm6B280 https://www.youtube.com/watch?v=mZBwsm6B280 and am just glad that nothing I have ever needed random sampling for has ever been important :D [1] please don't use this blindly, I'm really just going off very old recollection, if you need it google random sphere sampling :D