Since the Great Depression of the 1930s. the link between the suicide rate and the state of the economy has been the subject of much research. Research exploring this link using regression analysis was reported in the .lournal of Socio-Economics (Spriny.

1992). The rcsearchers collected data from a 45-year period on the following variables:

y = Suicide rate xl = Unemployment rate x2 = Percentage of females in the labor force xg = Divorce rate x4 = Logarithm of Gross National Product (GNP)

x5 = Annual percent change in GNP One of the models explored by the researchers was 7 multiple regrcssion model relating y to linear terms 111 x, through x5. The least squares model below resulted

(the observed significance levels of the /3 estimatr.

are shown in parentheses beneath the estimates):

9 = .002 + .0204xl - .0231x2 + ,0765~~ + .2760x4 t .00181

(.002) (.02) (>.lo) (>.lo) p.10 1 R2 = .45

a. Interpret the value of R2. IS there sufficient i.11 dence to indicate that the modcl is useful for prt dicting the suicide rate? Use a = .05.

b. Interpret each of the coefficients in the model,and each of the corrcsponding significance levels.

c. Is there sufficient evidence to indicate that the un employment rate is a useful predictor of the suic~d~

rate? Use a = .05.