As part of a class research project, a group of three student researchers, Ed, Ted, and Fred, decided to study the effects of physical attractiveness on ratings of success. Participants looked at a set of five photos of highly attractive people, a set of five photos of moderately attractive people, and a set of five photos of unattractive people. The photos are randomly presented, and previous research has identified the appropriateness of each photo. To get a good cross-section of students, the researchers decided to test three types of students: psychology majors, business majors, and chemistry majors. In order to collect the data more quickly, each researcher will test a different group of students. By random process it was determined that the psychology majors will be tested by Ed, the business majors will be tested by Ted, and the chemistry majors will be tested by Fred.