Problems 435
(b) Determine an interval that, with 95 percent confidence, will contain the
average blood pressure of all individuals of the preceding type that are
45 years old and weigh 180 pounds.
(c) Determine an interval that, with 95 percent confidence, will contain the
blood pressure of a given individual of the preceding type who is 45 years old
and weighs 180 pounds.
54.A recently completed study attempted to relate job satisfaction to income (in
1,000s) and seniority for a random sample of 9 municipal workers. The job sat-
isfaction value given for each worker is his or her own assessment of such, with a
score of 1 being the lowest and 10 being the highest. The following data resulted.Yearly Income Years on the Job Job Satisfaction
27 8 5.6
22 4 6.3
34 12 6.8
28 9 6.7
36 16 7.0
39 14 7.7
33 10 7.0
42 15 8.0
46 22 7.8(a) Estimate the regression parameters.
(b) What qualitative conclusions can you draw about how job satisfaction changes
when income remains fixed and the number of years of service increases?
(c) Predict the job satisfaction of an employee who has spent 5 years on the job
and earns a yearly salary of $31,000.
55.Suppose in Problem 54 that job satisfaction was related solely to years on the job,
with the following data resulting.Years on the Job Job Satisfaction
8 5.6
4 6.3
12 6.8
9 6.7
16 7.0
14 7.7
10 7.0
15 8.0
22 7.8