12.30 An app for tracking alcohol use, and ANOVA: Researchers investigated the use of an app for tracking alcohol consumption on the number of drinks a person consumed over a 3-week period. Participants logged each time they had a drink, and the researchers summed the number of drinks that each participant had each week. The researchers analyzed whether there was a significant difference in the number of drinks consumed across the 3 weeks of the study (Poulton et al., 2018). Let’s imagine that we’ve redesigned their study to add a second independent variable: Researchers randomly assigned half of the participants to receive a daily reminder to log their drinks and half received no reminder.

a. What are the independent variables and their levels?

b. What kind of ANOVA would we use? 12.31 Health-related myths and the type of ANOVA: Consider the study we used as an example for a two-way between-groups ANOVA in this chapter. Older and younger people were randomly assigned to hear either one repetition or three repetitions of a health-related myth, accompanied by the accurate information that “busted” the myth.

a. Explain why this study would be analyzed with a betweengroups ANOVA.

b. How could this study be redesigned to use a within-groups ANOVA? (Hint: Think long term.) 12.32 Memory and choosing the type of ANOVA: In a fictional study, a cognitive psychologist studied memory for names after a group activity. The researcher randomly assigned 120 participants to one of three conditions: (1) group members introduced themselves once, (2) group members were introduced by the experimenter and by themselves, and (3) group members were introduced by the experimenter and themselves, and they wore name tags throughout the group activity.

a. How could the researcher redesign this study so it would be analyzed with a two-way between-groups ANOVA? Be specific. (Note: There are several possible ways that the researcher could do this.)

b. How could the researcher redesign this study so it would be analyzed with a two-way mixed-design ANOVA? Be specific.