Question 8

Studies are often conducted to examine the contribution of genetics or environment on behavioral characteristics. One such study examined how much time (hours daily) individuals spent watching television. The data for nine participants are listed in the table below.

Amount of Time Spent Watching TV

Adopted Children Adopted Parents

X Y XY

2 1 2

3 4 12

6 2 12

1 0 0

3 0 0

0 3 0

5 2 10

2 3 6

5 3 15

X = 27 Y = 18 57

SSx = ___ SSy = ____

M_X = 3 M_{Y =} 2

a. Calculate SP using either method, and then calculate r. (8 points)

SP =

r =

b. Determine the significance of this correlation at alpha .05, two-tailed. Give the critical value and state whether or not there is a significant association between the two variables. (4 pts.)

df = ; CV =

c. Interpret the meaning of this correlation in terms of the problem. What is the direction of the relationship between years of hospitalization and orientation score? (4 points)

d. Find the regression equation for predicting Y from X. (4 points)

e. Calculate the predicted time adopted parents spent watching television whose children spent 4 and 7 hours, respectively. (3 points)