Testing a Lie Detector Did the Subject Actually Lie? No ( Did not Lie) Yes ( Lied) Polygraph test indicated that the subject lied 15 42 Polygraph test indicated that the subject did not lie 32 9 Use a...

Testing a Lie Detector

                                                 Did the Subject Actually Lie?

Use a 0.05 significance level to test the claim that whether a subject lie is independent of the polygraph test indication.

Given test statistic X 2 = 25.571

A) Find the expected value E for the first cell, where the observed frequency is 15.

B) Identify H 0 a n d H 1

C) Find the critical value

D) Is it reject H 0 or fail to reject