Which of the following statements about experimental research is most correct?
A) Finding an r coefficient of 0.9 indicates that that your independent variable had a strong effect on your dependent variable.
B) Using a within-subject design may lead to significant results because subjects got better at the task the second time they performed it.
C) Collecting data should be done by someone that knows the hypothesis and conditions to make sure it is done properly.
D) Assigning participants to conditions should be done according to criteria that the experimenter thinks are unrelated to the hypothesis, such as gender.
Answer: B