We are given here that:
P(HIV) = 0.01, therefore P(no HIV) = 1 - 0.01 = 0.99
Also, for HIV antibodies people, we have here:
P( + | HIV) = 0.9985 and therefore P(- | HIV) = 1 - 0.9985 =
0.0015
P( + | no HIV) = 0.006 and therefore P(- | HIV) = 1 - 0.006 =
0.994
a) From the above computed probabilities, the decision tree here is obtained as:
b) The joint probability distribution table here is given as:
Positive Result | Negative Result | |
HIV antibodies | 0.01*0.9985 = 0.009985 | 0.01*0.0015 = 0.000015 |
No HIV | 0.99*0.006 = 0.00594 | 0.99*0.994 = 0.98406 |
Enzyme immunoassay (EIA) tests are used to screen blood specimens for the presence of antibodies to...
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