Problem

Polygraph Test. Suppose that a polygraph is 85% accurate (it will correctly detect 85% of...

Polygraph Test. Suppose that a polygraph is 85% accurate (it will correctly detect 85% of people who are lying and it will correctly detect 85% of people who are telling the truth). The 2000 employees of a company are given a polygraph test during which they are asked whether they use drugs. All of them deny drug use, when, in fact, 1% of the employees actually use drugs. Assume that anyone whom the polygraph operator finds untruthful is accused of lying.

a. Verify that the entries in the table below follow from the given information. Explain each entry.

 

Users

Non-users

Total

Test Finds Employee Lying

17

297

314

Test Finds Employee Truthful

3

1683

1686

Total

20

1980

2000


b. How many employees are accused of lying? Of these, how many were actually lying and how many were telling the truth? What percentage of those accused of lying were falsely accused?


c. How many employees are found truthful? Of these, how many were actually truthful? What percentage of those found truthful really were truthful?

Step-by-Step Solution

Request Professional Solution

Request Solution!

We need at least 10 more requests to produce the solution.

0 / 10 have requested this problem solution

The more requests, the faster the answer.

Request! (Login Required)


All students who have requested the solution will be notified once they are available.
Add your Solution
Textbook Solutions and Answers Search
Solutions For Problems in Chapter 3E