Depressed patients were randomly assigned to one of threegroups: a placebo group, a group that received a moderate dose ofthe drug, and a group that received a high dose of the drug. Afterfour weeks of treatment, the patients completed the Beck DepressionInventory. The higher the score, the more depressed thepatient.
We are now also interested if a patient's weight has an effecton the drug's effectiveness. Patients were categorized as eitherunderweight, overweight, or 'medium weight'.Ă‚Â Ă‚Â Theserevised data are presented below. Use the Microsoft Excel \"AnovaSingle-Factor\" Data Analysis tool to conduct a 2-wayANOVA test for the data in the following table:
| Placebo | Moderate Dose | High Dose |
| underweight | 42 | 22 | 13 |
| underweight | 52 | 19 | 14 |
| medweight | 41 | 31 | 12 |
| medweight | 41 | 21 | 19 |
| overweight | 39 | 8 | 10 |
| overweight | 33 | 23 | 0 |
- Should this be a 2-way test WITH replication or WITHOUTreplication?
- What are the three Questions, incontext, that we want our ANOVA to answer?
- What are your threeanswers?Ă‚Â Ă‚Â Use the group and interactionconfidence levels obtained by way of the Excel ANOVA output table'sp-values.Ă‚Â Ă‚Â State your answers in terms of dose andweight.
