Dr. Guidry conducts a study examining the relationship between the number of friends one has and the experience of daily stress and life satisfaction. She randomly samples 1,500 elderly men and women in the Memphis, Tennessee, area in the southern United States. Below are her findings. < Life satisfaction and experience of daily stress: r = -.57 ( p = .01) < Number of friends one has and experience of daily stress: r = .09, not sig. < Number of friends one has and life satisfaction: r = .36 ( p = .04) Dr. Oswald submits her study for publication in a scientific journal. If one of the peer reviewers is concerned about the external validity of her study, which of the following is the most important aspect of Dr. Oswald’s study to consider?
a. Outliers
b. Moderators
c. Random
d. Curvilinear scores