SPSS

College of Doctoral Studies

RES-845: Module 8 Problem Set

Factorial (2 × 3) MANOVA

This study investigates the symptomatic improvement (measured by indexes of both worry and general emotion) of three different anxiety treatments for females and males. We are therefore interested not only in gender differences and treatment differences but also in whether or not gender moderates the effectiveness of the treatments (i.e., whether gender significantly interacts with treatment). To address these issues we use a factorial MANOVA design.

Variables in study:

• Treatment: 1 = medication; 2 = psychotherapy; 3 = placebo

• Sex: 1 = male; 0 = female

• Worry scale

• Emotion scale

Using the SPSS data file for Module 8 (located in Topic Materials), answer the following questions:

1. Is there a sufficient correlation between the dependent variables to justify the use of MANOVA?

2. Was the assumption of equality of covariance matrices violated? Explain.

3. Is there a statistically significant multivariate interaction effect? Identify the dependent variable(s) of this interaction effect.

4. What would be the proper follow-up tests for a statistically significant interaction effect?

5. Identify the proper post hoc analyses for any statistically significant univariate effects. Explain your answer.

6. Is there a statistically significant multivariate gender effect on the dependent variate?

7. Why would a researcher conduct a MANOVA instead of several ANOVAs?

8. Write a results section for this research.