It is known that whether or not a person has cancer is directly influenced by whether she is exposed to second-hand smoke and whether she smokes. Both of these things are affected by whether her parents smoke. Cancer reduces a person’s life expectancy.

(i)Draw the Bayesian Belief Network for the above situation.

(ii)Associate a conditional probability table for each node.

1.Draw the Bayesian Belief Network for the above situation.

PS – Person’s Parents Smoke

P – Person Smokes

S – Person exposed to Second-hand Smoke

C – Person has Cancer

LR – Person’s Life Expectancy is reduced

2.Associate a conditional probability table for each node.

CPT (P)

PS P(P=true | PS)

True

False
CPT (S)

PS P(S=true | PS)

True

False

CPT (C)

PS P(C=true | P, S)

True True

False True

True False

False False

CPT (LR)

C P(LR=true | C)

True

False