Identify the independent variables and their levels

Identify the independent variables and their levels.

Identify the dependent variable.

Described the design. Include the number of levels of each IV and whether it is independent groups, within-groups or mixed (independent/within or participant/independent or participant/within).

Assume that any difference is a significant difference and

Describe the main effects.

Draw a figure of the interaction and describe the interaction.

Problem A

The purpose of this study was to examine the effect of exercise and music on stress. Undergraduates were randomly assigned to either exercise for 30 minutes or to rest. They were also randomly assigned to listen to the music of their choice or to have no music. After the 30 minutes the researchers used a blood test to measure levels of the stress hormone cortisol. Here are the results reported in micrograms of cortisol per deciliter (lower scores indicate less stress hormone):

Music No Music

Rest 15 17

Exercise 5 7

Problem B

In a study of the effect of relatedness on memory for words, participants saw a list of 20 positive and 20 negative personality traits (e.g., generous or selfish) presented on computer in counterbalanced order. Participants were randomly assigned to rate either themselves or their best friend on the traits. After the ratings were finished, all participants were given surprise memory test and the researcher counted the number of traits that each person recalled.

self friend

positive 16.00 16.00

negative 10.00 10.00

Problem C

The makers of a new drug for panic disorder claim it is effective for people who have had long-term panic disorder (5 or more years) and for people who have short-term panic disorder (2 months or less). To study this claim, 60 long-term patients were randomly assigned to receive either the drug or a placebo. In addition, 60 short-term patients were randomly assigned to receive either the drug or a placebo. After 3 months, all patients were evaluated by a clinical psychologist who rated the severity of their symptoms on a scale from 1-not severe to 1—extremely severe. Here are the results:

Placebo Drug

Long-term patient 8 4

Short-term patient 2 2

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