Description
Ben is interested in predicting patient relapses that occur after participation in an intensive inpatient substance abuse program. He has data from 120 men who are at least four years beyond their initial admission to the program. Upon entry into the treatment program, the men were evaluated with respect to their psychological state and, in particular, on depression, propensity for substance abuse, and daily life stress. In addition, they completed two measures of social supportamount of social support available to them (number of close relationships) and perceptions of the quality of their social support. Ben also has a record of which patients relapsed and which have not.
Open the file Data Week 3.sav for Bens SPSS file, which contains 120 cases and three psychological state variables (named depress for depression, subst for substance abuse, and stress for daily life stress), two social support predictors (named amt_ss for amount of social support and per_ss for perception of social support), one dichotomous relapse variable (named relapse).
Conduct a discriminant analysis to distinguish between patients who have relapsed and those who have not. (Tip: You may use your SPSS software help file to conduct the analysis if you are unfamiliar with the procedure or other resources included for this course.) Then, write a paper in which you identify and explain the following items:
- Relapse vs. non-relapse group means for daily life stress
- Relapse group vs. non-relapse group means for quality of social support
- Univariate ANOVA F value for depression
- Univariate ANOVA F value for substance abuse
- Univariate ANOVA F value for amount social support
- Univariate ANOVA F value for amount of daily life stress
- ?2 associated with the discriminant function
- What percentage of patients are correctly classified? What is the overall percentage of patients correctly classified as relapsed versus non-relapsed?
- Which predictor variables contribute the most to discriminating between relapsed and non-relapsed patients?
- Create a combined groups plot to show the classification of the two groups.
