Matched or Paired Samples · Exercise 20

An experiment is conducted to show that blood pressure can be consciously reduced in people trained in a “biofeedback exercise program.” Six subjects were randomly selected and blood pressure measurements were recorded before and after the training. The difference between blood pressures was calculated (after - before) producing the following results: ${\left(\bar{x}\right)}_d$ = −10.2 s_d = 8.4. Using the data, test the hypothesis that the blood pressure has decreased after the training.

If α = 0.05, the p-value and the conclusion are

(a) 0.0014; There is sufficient evidence to conclude that the blood pressure decreased after the training.
(b) 0.0014; There is sufficient evidence to conclude that the blood pressure increased after the training.
(c) 0.0155; There is sufficient evidence to conclude that the blood pressure decreased after the training.
(d) 0.0155; There is sufficient evidence to conclude that the blood pressure increased after the training.

OpenStax, Introductory Statistics 2e · §10.4 Matched or Paired Samples · Exercise 20