In Exercises, refer to Table, included with the Chapter Problem. In each case, assume that 1 of the 1000 test subjects is randomly selected.
Inverse Probabilities
a. Find P (negative test result | subject does not use drugs).
b. Find P (subject does not use drugs | negative test result).
c. Compare the results from parts (a) and (b). Are they equal?
Table Pre-Employment Drug Screening Results
|
Positive Test Result (Drug Use Is Indicated) |
Negative Test Result (Drug Use Is Not Indicated) |
Subject Uses Drugs |
44 (True Positive) |
6 (False Negative) |
Subject Is Not a Drug User |
90 (False Positive) |
860 (True Negative) |
Solution 22BSC
= 0.993