CV –COVID-19, S – Smokes, CH – Chills, F - Fever,
B – Bronchitis, C – Coughing, SB – Shortness of Breath.
Relationships:
CV influences CH, F, and B.
S influences B.
B influences C and SB.
Variable expressions:
P(CV) = 0.05
P(S) = 0.2
P(CH|CV) = 0.6
P(CH|¬CV) = 0.01
P(F|CV) = 0.8
P(F|¬CV) = 0.05
P(B|CV, S) = 0.95
P(B|CV,¬S) = 0.85
P(B|¬CV, S) = 0.7
P(B|¬CV, ¬S) = 0.01
P(SB|B) = 0.6
P(SB|¬B) = 0.02
P(C|B) = 0.95
P(C|¬B) = 0.07
(3) (A) Define and give the formula for computing the probability that patients who had the shortness of breath and fever had COVID-19. – The tense of verbs can be ignored.
(B) Which variables are irrelevant to compute (3)?
(C) Compute the probability in 3A by discarding the irrelevant variables.
3A. Equation (I think):
P(CV|SB, F) = (P(CV,SB,F))/(P(SB,F))= [P(CV)*P(SB│CV)*P(F|SB,CV)] / [P(SB)*P(F|SB)]
3B. irrelevant variables are CH and C.
3C. How do i compute final probability?