1. The following data show the number of class sessions missed during a semester of SOC221 and the final grade for a sample of 8 students selected at random.

Number of Sessions Missed Final Grade

(x) (y)

0 96

2 88

12 68

6 91

8 72

9 73

4 93

10 70

a. Plot the observed data on a scatterplot.

b. Using the method of least squares, determine the equation for the estimated regression line using number of sessions missed to predict final grade.That is, calculate the values of the constant and regression coefficient.

c. Give an interpretation of the estimated regression equation (i.e., what is the meaning of a, and what is the meaning of b?)

d. What is the predicted final grade for someone who misses 7 sessions?

e. Compute and interpret the correlation coefficient.

f. Compute and interpret the coefficient of determination.

g. Test the null hypothesis that, in the population, the correlation between sessions missed and final grade is equal to zero.Use = .05.