5&6

5 1 point A researcher wants to test whether taking part in exercise will boost the immune system of people with AIDS. Her expectation is that exercising will enhance immune functioning. For this purpose, she recruits a large pool of adults with AIDS and randomly assigns half to an hour-long aerobics class that meets once a week for six months and half to a book club that meets for the same duration at the same frequency. The table below presents the data she collected after the 6-month intervention. A higher score indicates better immune functioning. The immune functioning of the two groups was the same prior to the intervention. She found that the critical value of the test statistic is 1.7, and the observed value of the test statistic is 1.8. All of the assumptions for the relevant statistical test to be valid were met. 1 What should the researcher conclude? Exercising boosts immune function 2 Exercising has no effect on immune function O Participating in a social support group boosts immune function 3 O Having AIDS has an effect on immune function 4 6 1 point 5 The following summary table contains data from an experiment comparing the efficacy of different types of treatment of major depression. Participants in this study were randomly assigned to receive one of several different therapies for major depression, and their mood was measured before and after treatment. How many types of treatment were compared? 6 Source ss df MS F Between 100 14 7 Within Total 44 O 5 8 a 9 O A 10