A research study was conducted to examine the clinical efficacy of a new antidepressant. Depressed patients were randomly assigned to one of three groups: a placebo group, a group that received a low dose of the drug, and a group that received a moderate dose of the drug. After four weeks of treatment, the patients completed the Beck Depression Inventory. The higher the score, the more depressed the patient. The data are presented below. Compute the appropriate test.
Placebo Low Dose Moderate Dose
38 22 14
47 19 26
39 8 11
25 23 18
42 31 5
1. What is your computed answer? 2275.733
2. What would be the null hypothesis in this study?
3. What would be the alternate hypothesis?
4. What probability level did you choose and why? 0
5. What is your Fcrit? 11.26657
6. Is there a significant difference between the groups? No
7. If there is a significant difference, where specifically are the differences? No
9. Each SSBG portion must be divided by _____.
1. MSBG - 742.4667
2. MSWG - 65.9
3. SStot
4. Degrees of freedom - 2