A compulsive researcher who wants to cover all possibilities might throw in the total score on perceived vulnerability (Total) as well as PVLoss. (The total includes vulnerability to accidents,...

A compulsive researcher who wants to cover all possibilities might throw in the total score on perceived vulnerability (Total) as well as PVLoss. (The total includes vulnerability to accidents, illness, and life-style related problems.)

a. Run this analysis adding PVTotal to the variables used in Exercise 15.24.

b. What effect did the inclusion of PVTotal have on R²? What effect did it have on the standard error of the regression coefficient for PVLoss? If your program will also give you tolerance and VIF, what effect does the inclusion of PVTotal have on them?

c. What would you conclude about the addition of PVTotal to our model?

Use the data set Mireault.dat from Mireault (1990), described in the Appendix and found on the Web site for this book, to examine the relationship between current levels of depression and other variables. A reasonable model might propose that depression (DepressT) is a function of (1) the person’s current perceived level of vulnerability to additional loss (PVLoss), (2) the person’s level of social support (SuppTotl), and (3) the age at which the person lost a parent during childhood (AgeAtLos). Use any statistical package to evaluate the model outlined here. (Because only subjects in Group 1 lost a parent to death during childhood, your analysis will be restricted to that group.)