Hastings comments on Bayesian Scenario: Snipers & Soldiers

Hastings 27 Feb 2023 2:48 UTC
3 points
0
It was fun to actually get out Bayes rule in a bayesian reasoning challenge, and gratifying to see that I got the same number as reveal P(Sniper). When I clicked “stick out helmet” a second time, I had already clicked “reveal P(sniper)” to check my work from the single shot calculation, and it live updated to the two shot calculation- spoilers?
```
P(S) = .3
P(H|S) = .6
P(H|^S) = .4
P(S) P(H | S) = P(H) P(S | H)
P(H) = (P(H | S) P(S) + P(H | ^S) P(^S) )
P(H) = .3 * .6 + .7 * .4 = .459999
P(S | H ) = P(S) P(H | S) / P(H) =
.3 * .6 / .459999 = 0.3913051984895619
```