題組內容

3. A 10-year study conducted by the American Heart Association provided data on how age, blood pressure, and smoking relate to the risk of stroke. The data are from 20 individuals. Risk is interpreted as the probability (times 100) that the patient will have a stroke over the next 10-year period. For the smoking variable, define a dummy variable with 1 indicating a smoker and 0 indicating a nonsmoker. The regression result is follows.


From ANOVA table, Sum of Square Residual is 530.21, Sum of Square Total is 4190.95

(3) What percentage of the variability in risk of stroke can be explained by the linear effect of the age, blood pressure and he/she is a smoker or not? (5%)