Question: A sociologist is interested in the relation between x = number of job changes and y = annual salary (in thousands of dollars) for people living in the Nashville area. A random sample of 10 people employed in Nashville provided the following information:

x (number of job changes) ?? 0 5 3 6 2_ 3 9 6 7 1

y (salary in $1000s) ?? 71 39 41 58 67 54 36 49 50 63

a. Draw a scatter diagram for the data.

b. Find , a , b , and the equation of the least-squares line.

c. If someone had x = 3 job changes, what does the line predict for y , the annual salary?

d. Find a 95% confidence interval for the prediction in part c.

e. Find the sample correlation coefficient r .

f. Test the correlation coefficient for significance at the 90% confidence level.

g. Calculate the Spearman rank correlation coefficient for these data.