Re: Q20
Need help in verifying if below understanding is correct ?
The Bayesian:
P(h=f | D) = P(D | h=f) * P(h=f) / P(D)
For this Q, we are given:
P(h=f) is uniform in [0,1]
D: one-person-with-heart-attack
Pick f = c (constant)
To simplify, I assume that h and f are a discrete random-variables with 10 possible values from (0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0)
and each is equally likely with P=1/10. Essentially simplifying here to make P(h=f) a pmf which is actually a pdf.
Now:
P (D | h=f)
= Pr( one-person-with-heart-attack | h=f )
= Probability of one-person-with-heart-attack, given (h=f)
= c
( because if h=f were given, then the Prob of one picked person getting heart-attack is c, as defined by f )
Plug in above to get:
P(h=f | D) = c * P(h=f) / P(D)
Does above sound correct ?
Also P(D) =1 in this case ?
Thanks.
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