1:25 PM Sat Nov 2
79%
G er & Left Ventricle Fu X G define conduit - X G hermit thrush bi X A Homework #3, X C Get Homework X C Information Fro X
+
10
< > C
webassign.net
. . .
Only 0.1% of the individuals in a certain population have a particular disease (an incidence rate of 0.001). Of those who have the
disease, 95% test positive when a certain diagnostic test is applied. Of those who do not have the disease, 90% test negative
when the test is applied. Suppose that an individual from this population is randomly selected and given the test.
(a) Construct a tree diagram having two first-generation branches, for has disease and doesn't have disease, and two second-
generation branches leading out from each of these, for positive test and negative test. Then enter appropriate probabilities
on the four branches.
Pos Test
Disease
Neg Test
Pos Test
NoDisease
Neg Test
(b) Use the general multiplication rule to calculate P(has disease and positive test).
0.00095
V
(c)
Calculate P(positive test).
0. 1094
X
(d) Calculate P(has disease | positive test). (Round your answer to five decimal places.)
0.0087
X