Conversation

Visa ✈️ SF (Aug 2-14)
@visakanv
i'm going to bed but let's try and set up a game 1. reply with an interest, a picture, a quote, whatever  – something random that you'd like to talk about with someone. ask a question, state an observation 2. reply to someone else in the replies enjoy your new friends
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irα!!
@solarsystern
can u send me a link that explains this a lil past 280 characters i feel like i'm 80% towards understanding why this sucks
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QC (in Berlin 7/29-??? w/ COVID 😷)
@QiaochuYuan
idk a place where this is spelled out but like okay take a random walk on a 2D square grid where you go up, down, left or right with probability 1/4 each. sample the walk a bunch of times and make a plot of where you end up after like a million steps. you’ll get a 2D gaussian
Image
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shb
@himbodhisattva
Is this one run showing intermediate steps? Or is this multiple runs of the simulation? Also what does the yellow mean?
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QC (in Berlin 7/29-??? w/ COVID 😷)
@QiaochuYuan
idk i just pulled the first image off google that looked right. i don’t know what the yellow means. i think this should be multiple runs and showing the final locations of the walks only. pictures of the walks themselves are also interesting but not what i’m getting at
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shb
@himbodhisattva
well x and y are independent, so we can think about the 1 dimensional case? and your end location doesn't depend on the order, just the final totals. so for Up and Down, ending up r from the origin, P(r) = P(U - D) = P(U) + P(-D), so CLT says r will be normal? is that what's 🤯?
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@xobnu
Replying to
@QiaochuYuan
@sam_havens
and 2 others
Is there something unsatisfying about just attributing this to the sheer number of steps? Take two points (a,b) distance ~r from origin. For every path from the origin to a you can draw a near-identical path from the origin to b (using just grid-points) due to sheer granularity