Po-Shen Loh is a professor at Carnegie Mellon University and a coach for the US Math Olympiad. He is also a social entrepreneur where he has his used his passion and expertise in mathematics in the service of education (expii.com) and epidemiology (novid.org).
In this episode, we discuss the mathematics behind Loh's novel approach to contact tracing in the fight against COVID, which involves a beautiful blend of graph theory and computer science.
Originally published on March 3, 2022 on Youtube: https://youtu.be/8CLxLBMGxLE
Patreon: https://www.patreon.com/timothynguyen
00:01:11 : About Po-Shen Loh00:03:49 : NOVID app00:04:47 : Graph theory and quarantining00:08:39 : Graph adjacency definition for contact tracing00:16:01 : Six degrees of separation away from anyone?00:21:13 : Getting the game theory and incentives right00:30:40 : Conventional approach to contact tracing00:34:47 : Comparison with big tech00:39:19 : Neighbor search complexity00:45:15 : Watts-Strogatz small networks phenomenon00:48:37 : Storing neighborhood information00:57:00 : Random hashing to reduce computational burden01:05:24 : Logarithmic probing of sparsity01:09:56 : Two math PhDs struggle to do division01:11:17 : Bitwise-or for union of bounded sets01:16:21 : Step back and recap01:26:15 : Tradeoff between number of hash bins and sparsity01:29:12 : ConclusionPo-Shen Loh. "Flipping the Perspective in Contact Tracing" https://arxiv.org/abs/2010.03806