Stress levels were recorded during a true answer and a false answer given by each of six people in a study of lie-detecting equipment, based on the idea that the stress involved in telling a lie can be measured. The results are shown in Table 16.4.4.
a. Was everyone€™s stress level higher during a false answer than during a true answer?
b. How many had more stress during a true answer? During a false answer?
c. Find the modified sample size.
d. Use the nonparametric sign test for the differences to tell whether there is a significant difference in stress level between true and false answers.

TABLE 16.4.4 Stress Levels Vocal Stress Level Person False Answer True Answer 12.8 8.5 3.4 5.0 10.1 11.2 13.1 9.6 4.8 4.6 11.0 12.1