Violent lyrics and aggressiveness. Check the assumptions for the factorial design ANOVA in Exercise 12.38 (p. 661).

Exercise 12.38

Violent lyrics and aggressiveness. In the Journal of Personality and Social Psychology (May 2003), psychologists investigated the potentially harmful effects of violent music lyrics. The researchers theorized that listening to a song with violent lyrics will lead to more violent thoughts and actions. A total of 60 undergraduate college students participated in one experiment designed by the researchers. Half of the students were volunteers and half were required to participate as part of their introductory psychology class. Each student listened to a song by the group ‘‘Tool’’—half the students were randomly assigned a song with violent lyrics and half assigned a song with nonviolent lyrics. Consequently, the experiment used a 2 × 2 factorial design with the factors Song (violent, nonviolent) and Pool (volunteer, psychology class). After listening to the song, each student was given a list of word pairs and asked to rate the similarity of each word in the pair on a 7-point scale. One word in each pair was aggressive in meaning (e.g., choke) and the other was ambiguous (e.g., night). An aggressive cognition score was assigned based on the average word-pair scores. (The higher the score, the more the subject associated an ambiguous word with a violent word.) The data (simulated) are shown below. Conduct a complete analysis of variance on the data.